US20050123659A1 - Pizza making method and system - Google Patents

Abstract

The invention provides an automated method and apparatus for pizza production which is initiated by individual order placement and uses only fresh ingredients (no ingredients are frozen, pre-prepared or pre-cooked). Each dough portion is individually and mechanically prepared from flour and other fresh, pre-proportioned ingredients. The dough portion passes through a series of shaping and pre-heating processing stations to prepare a flattened and partially baked pizza base. Using a preheated or continuously heated conveying tray, the pizza base passes under a number of metering and distribution devices for selected application of tomato sauce and/or various other toppings according to the order. Baking occurs in one of multiple ovens to complete pizza preparation. Multiple ovens are provided to facilitate the automated preparation of multiple pizzas at any given time. A tray conveying system transports one or more trays through the various processing stations to accommodate multiple orders at the same time.

Description

RELATED APPLICATIONS
• The present application is a continuation-in-part of applicant's co-pending U.S. patent application Ser. No. 09/832,409, filed 11 Apr. 2001, entitled “Method and Device for Producing Pizza”, which application is a divisional application of U.S. patent application Ser. No. 09/294,702, filed 19 Apr. 1999 (now U.S. Pat. No. 6,245,370), which application is a continuation-in-part of Patent Cooperation Treaty Application No. PCT/EP98/05093, filed 12 Aug. 1998, which application claims priority to Italian Patent Application No. BZ97A000044, filed 19 Aug. 1997.
• The present application is a continuation-in-part of Patent Cooperation Treaty Application No. PCT/EP01/04656, filed 25 Apr. 2001, entitled “Dough Mixer with Metering Device”, which application claims priority to European Patent Application No. 00109611.4, filed 5 May 2000.
• The present application claims priority under 35 USC § 119(a) to Italian Patent Application No. BZ2001A000033, filed 7 Jun. 2001, entitled “Pizza Cutting and Transfer Device”.
• The present application claims priority under 35 USC § 119(a) to European Patent Application No. 01113720.5, filed 5 Jun. 2001, entitled “Metering Device for Liquid or Cream-like Components for Garnishing Food Products”.
• The present application claims priority under 35 USC § 119(e) to U.S. Provisional Patent Application No. 60/297,160, filed 8 Jun. 2001, entitled “An Automatic Pizza Making Method and System”. U.S. Provisional Patent Application No. 60/297,160 is incorporated in its entirety by this reference.
FIELD OF THE INVENTION
• The present invention relates generally to pizza making, and more particularly to an automated method and system for making pizza from fresh ingredients according to individual orders.
BACKGROUND OF THE INVENTION
• Methods and systems are known for the automatic industrial production-line and mass-produced production of pizzas. These methods and systems essentially include the following work phases: preparation of dough including rising of the dough, extruding the dough creating a dough strand, cutting the dough strand into individual dough portions, processing the dough portions to flattened pizza bases, adding seasonings and toppings, baking, packaging for consumption within the expiration date or, respectively, for deep freezing.
• Systems employing the above-referenced methods are numerous for mass-production. Existing automated systems have accelerated pizza production by employing pre-treated dried granulate with seasonings and toppings applied to a pre-determined, large number of pizzas of the same variety on a continuous belt with baking in a tunnel oven. Some existing systems accelerate production by employing pre-produced, precooked and/or frozen dough portions and toppings.
• For the foregoing reasons, there is a need for an automatic pizza making method and system that provides fast, individual and completely fresh pizza preparation according to individual order placement.
• Dough Mixer
• Dough mixers for producing dough used in preparing foods are known which use one or two screw conveyors, or rotating mixing arms within fixed or rotating containers with vertical or angled axis or kneading elements rotating within a closed housing with a horizontal axis. Also known are smaller mechanical devices for preparing dough in the household; generally these include a cylindrical container with a vertical axis within which one or more agitator blades operate on a single drive shaft attached coaxially to the container axis.
• Information relevant to attempts to address dough mixers can be found in U.S. Pat. Nos. 5,486,049; 4,630,930; and 5,322,388. However, each of these references suffers from one or more disadvantages.
• The known devices are not designed for preparing individual dough portions per work cycle within relatively short periods of time and by charging with ingredients in individual portions; further, known devices do not provide that each dough portion prepared and discharged for shaping leaves no ingredients or dough residue inside the device. The known devices are also not designed to perform a periodic, completely automatic sterilization of the kneading chamber and elements.
• Also known in the art is the problem of charging kneading devices with relatively exact volumetric amounts of flour or flour-like ingredients which are hydroscopic. Such problems result from the tendency of flour-like materials to form accumulations or agglomerates inside the container, that varying the material volume above the metering mechanism strongly affects the metering process and that it is difficult to achieve an even filling and/or emptying of the metering chamber.
• For the foregoing reasons, there is a need for a dough mixer of simple, compact design which can be automatically sterilized, has an essentially cylindrical chamber with kneading rotation occurring about a horizontal axis to accommodate direct charging of consistently accurate and pre-metered amounts of material per work cycle while preventing accumulation of material in the container and/or metering chamber, the dough mixer quickly preparing, on demand, one individual dough portion suitable for preparation of one pizza by subsequent shaping, garnishing and baking.
• Tomato Sauce Dispenser
• Systems are known for mechanical metering and garnishing of pizza with tomato sauce or other liquid components. Most of these devices supply the sauce by tube, under pressure generated by a pump. Generally these systems are mounted on a production line above a passage area of the dough base to be garnished, the garnishing process occurring by free fall. Accordingly, uniform distribution of the sauce to the dough base requires several tubes or nozzles and air jets evenly spaced above the garnishing area to evenly distribute the sauce on the dough base.
• Known liquid dispensing systems have several disadvantages. Systems with a plurality of tubes and nozzles are unsuitable for liquids such as tomato sauce as tomato sauces are rarely homogenous in fluidity and texture. As such, the individual nozzles fed from one single supply tube rarely dispense equal quantities of the sauces. In addition, dispensing sauce from a plurality of tubes and nozzles creates cleaning and sanitation problems as the sauce often drips from the nozzles after product flow ceases. To prevent the product from spoiling, mold from forming and bacteria from breeding during downtimes, tubes must be exchanged often, resulting in increased production costs.
• Known liquid dispensing systems using air jets require high product homogeneity, accurate product metering and precise jet calibration based upon texture and volume of the liquid to be distributed. Air jet systems often distribute excessive product, insufficient product or provide intermittent distribution while continually experiencing cleaning problems.
• Other existing free falling systems require that the underlying dough base rotate about a vertical axis with sauce distributed in a spiral manner. These systems allot all movement to the dough base, whereas dispensing nozzles remain stationary. One disadvantage of these systems, if integrated into a production line for pizza, is the complication or exclusion to using traditional conveying systems to transport the dough base through the production line due to the requirement of rotating the dough base during sauce application. Thus, conveying systems must provide the additional capability of rotating the dough base over a portion of the production line. Or, the conveying system must transfer the dough base to a separate device to spin the dough base. Further complications arise when the production line requires that the dough base be heated during conveying and/or garnishing.
• For the foregoing reasons, there is a need for a tomato sauce dispenser that provides even sauce distribution on a dough base (regardless of sauce homogeneity), that performs in a production line having traditional conveying systems and/or conveying systems applying heat to the dough base during transport thereof through the production line, and also facilitates easy cleaning and maintenance.
• Oven
• Electric ovens employing electrical resistance, microwave generators (magnetrons), infrared lamps or induction units as a heat source for cooking relatively thin cakes, such as pizza and focaccia, are known, as are ovens employing one or more such heat sources in combination, such as ray or wave sources. These ovens are designed to cook or heat fresh or frozen foods, which may be precooked, in a relatively short time.
• Cooking time is important for industrial food-production processes and for automated machines that heat or cook food on the spot. Such machines commonly use cooking systems employing microwaves and/or infrared rays, sometimes in combination with electrical resistance. However, it takes approximately 80 seconds to cook and brown pizzas having a diameter of about 270 mm and total weight of about 320 g to 360 g.
• For the foregoing reasons, there is a need for an oven that can fully cook and brown fresh (not precooked) food in a shorter time period, without sacrificing the organoleptic and nutritional properties associated with traditional cooking.
• Automatic Cutting Device
• A number of devices exist for automatically cutting pizza or focaccia into slices, using plates provided with blades which operate vertically like a dinking die on the pizza being cut. The existing devices only cut the pizza, requiring specific devices to then transfer the cut pizza to the take-out box or other packaging.
• Furthermore, the known devices are not designed for easy cleaning and/or replacement of the parts that come into repeated contact with the pizza, thereby creating cleanliness and hygiene problems with both the cutting device and the transfer device.
• For the foregoing reasons, there is a need for a simple, combination cutting and transfer device which is easy to clean and uses some of the cutting movements to transfer the pizza, thereby expediting the pizza making process.
SUMMARY OF THE INVENTION
• The present invention is an automatic pizza making method and apparatus providing fast, individual and completely fresh pizza preparation according to individual order placement. The pizza making system is innovatively designed for production of fresh pizza by turn-key operation. The pizza making system comprises multiple processing stations that combine ingredients, namely, flour, water, salt, leveling agent, tomato sauce, cheese and assorted toppings such as sausage and pepperoni, to prepare and bake a pizza.
• Accordingly, it is an object of the present invention to furnish an automated method and a system for pizza production according to individual orders placed by selections from a list, the production employing only fresh ingredients (no pre-cooked and/or deep-frozen ingredients for the dough or toppings) with each pizza individually seasoned, spiced, garnished and baked in a short time and provided ready to eat.
• It is another object of the present invention to furnish the method and system such that the production process is performed hygienically, without human intervention and where periodic and automated washing and sterilization cycles are provided to maintain the system in a suitable hygienic state.
• It is a further object of the present invention to simply and periodically exchange system components that contact foodstuffs and are not otherwise subjected to the germicidal effect of elevated temperature.
• Dough Mixer
• The dough mixer of the automatic pizza making method and system of the present invention satisfies the need described above for dough mixers. The dough mixer has a simple, compact design providing automatic sterilization. The dough mixer has an essentially cylindrical chamber with kneading rotation occurring about a horizontal axis to accommodate direct charging of consistently accurate and pre-metered amounts of material per work cycle while preventing accumulation of material in the container and/or metering chamber. The dough mixer quickly prepares, on demand, one individual dough portion suitable for preparation of one pizza by subsequent shaping, garnishing and baking.
• Tomato Sauce Dispenser
• The tomato sauce dispenser of the automatic pizza making method and system of the present invention satisfies the need described above for liquid dispensers. The tomato sauce dispenser provides even sauce distribution on the dough base (regardless of sauce homogeneity), performs in a production line having traditional conveying systems and/or conveying systems which apply heat to the dough base during transport thereof through the production line, and facilitates easy cleaning and maintenance.
• Oven
• The oven of the automatic pizza making method and system of the present invention satisfies the need described above for ovens. The ovens of the present invention use infrared rays emitted in two different wavelength ranges by separate and specific sources, each differing in design, to produce specific heat within the top surface (toppings) of the pizza and within the thin cake (dough). The infrared rays are programmably cycled on and off, with wavelengths in a visible and near-infrared range penetrating deep into the dough, propagating in accordance with the laws of optics (especially in the presence of water molecules), while wavelengths in a far-infrared range are absorbed in the top surface of the pizza, to fully cook and brown a typical pizza in approximately 55 seconds.
• Automatic Cutting Device
• The automatic cutting device of the present invention provides a simple, easy-to-clean cutting and transfer device that uses some of its cutting movements to transfer the pizza. The present invention attaches a sheet that slides vertically by its own weight or by spring action to a side of a plate provided with blades. After cutting the pizza, the sheet holds the cut pizza in the cutting position as the plate that supports the pizza during cutting moves horizontally to drop the pizza onto a top box of a stack of take-out boxes disposed below. Alternatively, the sheet assists the transfer of the pizza onto a take-out box to one side as the entire cutting device moves laterally, lifting the plate provided with blades once the pizza is placed on the box.
• The present invention also provides blades that are easily detached from the supporting plate for replacement and cleaning, regardless of whether the blades are single-use or coated with a sheath or layer that can be removed easily at the end of a predetermined cutting cycle, thereby making the cutting device as hygienic as possible.
BRIEF DESCRIPTION OF THE DRAWINGS
• For the purpose of illustrating the invention, there is shown in the drawings a form that is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
• FIG. 1 illustrates a front elevation of the automatic pizza making system according to the present invention;
• FIG. 2 illustrates a top plan of the automatic pizza making system shown inFIG. 1;
• FIGS. 3aand3billustrate a left side elevation of the automatic pizza making system shown inFIG. 1,FIG. 3ashowing a dough punching device in an extended, non-operating position andFIG. 3bshowing the dough punching device in a retracted, operating position;
• FIG. 4 illustrates an elevation of the automatic pizza making system according to the plane4-4 inFIG. 1,FIG. 4 viewing through a refrigerator to a cutting device, two ovens and a tray conveying system;
• FIG. 5 illustrates a right side, partial sectional elevation of a flour container and dough mixer of the automatic pizza making system shown inFIG. 1;
• FIG. 6 illustrates a front sectional elevation of the flour container and the dough mixer shown inFIG. 5;
• FIGS. 7athrough7cillustrate a front sectional, a left side sectional and a top plan, respectfully, of a pre-former of the automatic pizza making system shown inFIG. 1;
• FIGS. 8aand8billustrate a left side, partial sectional elevation of a hot press of the automatic pizza making system shown inFIG. 1,FIG. 8ashowing an upper press portion andFIG. 8bshowing a lower press portion of the hot press;
• FIGS. 9aand9billustrate a left side, partial sectional and a top plan, respectfully, of the dough punching device of the automatic pizza making system shown inFIG. 1 (and detailed inFIGS. 3aand3b),FIG. 9ashowing the dough punching device in a retracted, operating position andFIG. 9bshowing the dough punching device in an extended, non-operating position;
• FIG. 10aillustrates a top plan of a tomato sauce dispenser of the automatic pizza making system shown inFIG. 1;
• FIG. 10billustrates a front section of the tomato sauce dispenser according to the plane II-II inFIG. 10a;
• FIG. 10cillustrates a side, partial section of the tomato sauce dispenser according to the plane III-III inFIG. 10b,FIG. 10cdetailing a carriage driven by a threaded spindle;
• FIG. 10dillustrates a top plan of a tomato sauce dispenser shown inFIG. 1 (without the case),FIG. 10dshowing a mounting for the threaded spindle and the carriage;
• FIGS. 11athrough11cillustrate a left side sectional, a front sectional and a bottom plan, respectfully, of a cheese or sausage dispenser of the automatic pizza making system shown inFIG. 1;
• FIGS. 12athrough12dillustrate a front partial sectional, a left side partial sectional, a top plan and a left side sectional detailing internal mechanisms, respectfully, of a pepperoni dispenser of the automatic pizza making system shown inFIG. 1;
• FIGS. 13athrough13dillustrate various side and front elevations of each of two ovens included in the automatic pizza making system shown inFIG. 1 withFIGS. 13eand13fdetailing the cooking method employed by the ovens;
• FIGS. 14athrough14cillustrate front views of one embodiment of an automatic cutting and transfer device of the present invention where a movable transfer plate is responsible for transferring a cut pizza into a box for packaging;
• FIGS. 14dthrough14fillustrate front, top and left side views, respectively, of another embodiment of an automatic cutting and transfer device of the present invention (and the embodiment shown in the automatic pizza making system ofFIG. 1), where the entire cutting device moves to transfer the cut pizza from a cutting position to a packaging position; and
• FIGS. 15athrough15fare left side elevations of the automatic pizza making system shown inFIG. 1 (close-up views ofFIGS. 3aand3b) illustrating, step by step, a dough shaping and dough punching process according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
• Referring now to the drawings, wherein like numerals indicate like elements, there is shown inFIGS. 1 through 4 an illustration of an automaticpizza making system20. The pizza making system includes aflour container22, adough mixer24, a water and levelingagent container26, a pre-former28, ahot press30, adough punching device32, a receivingrack34, a conveyingtray36, atray conveying system38, atomato sauce dispenser40, acheese dispenser42, apepperoni dispenser44, asausage dispenser46, arefrigerator48, afirst oven50, asecond oven52 and acutting device54.
• Flour Container and Dough Mixer (FIGS. 5 & 6)
• The dough mixer of the present invention is designed for preparing individual dough portions per each work cycle within relatively short periods of time and by charging with ingredients in individual portions. The dough mixer provides that every individual mixed dough portion that is rolled into a ball and is ready for shaping and baking can be discharged without leaving ingredients or dough residue inside the device. The dough mixer also performs a periodic, completely automatic sterilization of the kneading chamber and its kneading elements.
• The object of the flour container and dough mixer of the present invention is to create a dough mixer that has a simple and compact design, can be automatically sterilized, has an essentially cylindrical chamber with horizontal axis in which a kneading element operates with horizontally rotating axis, due to direct charging of the chamber with pre-metered ingredients per work cycle, to create in a short period of time a portion of dough which then is finally discharged as a mixed individual portion in the form of a ball and ready-made for subsequent shaping, garnishing, and baking or deep-freezing.
• To attain the flour container and dough mixer described above, a housing is designed having an inner chamber that is essentially cylindrical and has in its upper section, which corresponds to the charging region for the flour-like and possibly also liquid ingredients, as well as in the lower section, which corresponds to the discharge region, a surface area that runs parallel to the chamber axis and turns into the chamber casing surface. Within this chamber operates a rotating kneading element according to an axis that runs coaxially or parallel to the chamber axis. The rotating kneading element comprises at least one arm formed with one end attached radially to the end of a drive shaft, and on the other end of which at least one fixed bearing pin is attached cantilever with an axis running parallel to the rotational axis of the drive shaft; a freely turning sleeve is placed by means of a recessed hole on top of this bearing pin with rounded terminal ends on both sides. As an advantageous feature are two arms extending radially from the same drive shaft, which are oriented to each other longitudinally or are in the same level but are at a certain angle to each other, and each of these arms carries a bearing pin with a rotating sleeve placed on top parallel to the rotational axis, preferably with a different distance to the rotational axis of the drive shaft. While these bearing pins, which are equipped with rotating sleeves, are in motion, the dough is compressed, rolled and rolled thin repeatedly in particular in the lower region of the chamber with the level surface section that turns into the curved casing surface. If a plurality of these sleeves are operated, they can have varying outside diameters, cross-sections, and shapes depending on the consistency of the dough being produced and/or the properties of the ingredients and/or the percentage of liquid ingredients. The invention provides further for the interchangeability and/or the change in the number of the sleeves mentioned, depending on the properties of the ingredients and/or the dough that is being prepared.
• Due to the charging of the chamber with dry flour-like ingredients, the kneading element carries out the work phase with the purpose of homogenizing and aerating the dried ingredients by rotating at a relatively high speed in order to achieve a thorough mixing of the ingredients introduced, and their preparation for the subsequent introduction of liquid ingredients, which ensures that they are evenly absorbed, and the dough agglomerate is then created with a markedly reduced rotational speed; by further reducing the speed, a mixing and homogenization of the dough mass is achieved, which then, upon further reduction in rotation speed, is compressed and rolled into balls, which as such are discharged in part due to gravity by opening the discharge opening in the region corresponding to the lower level surface section of the chamber.
• The individual inner surfaces and surface areas of the dough mixer chamber have surface transitions with rounded areas with the largest possible radius, including the rotating arms or the sleeves of the kneading elements, all have rounded forms, and thus the chamber space is free of edges or recesses on which dough residue could stick that is not discharged along with the individual portion, due to the process by which the dough is kneaded and rolled into balls. After rolling into balls and discharging, the chamber and the kneading elements are thus free of any residue from the dough and ingredients. This form further allows them to be sterilized by means of hot air, through which small amounts of sticky dough residue are removed in the air current due to the drying process and the application of pressure.
• The front surface of the chamber, which is across from the second front surface from which the drive shaft for the kneading element projects, can have a level, conical, more or less rounded form that protrudes against the drive shaft, with its axis extending coaxially to the rotational axis of the drive shaft or parallel to it preferably in the upper level of the chamber. By means of a distinctive conical or nose cone form, the rotating sleeves of the kneading element can roll the dough thin even with this shape. Further, the housing wall corresponding to this front interior surface with more or less distinctive shape can be replaced by another housing wall, in order to change the volume of the chamber by changing the distance between the front circular surfaces; in this case, the sleeves on the kneading element are also replaced by sleeves with the appropriate longitudinal extension.
• Preferably, the liquid ingredient(s) for preparing the dough are introduced through one or more openings in the central region at the front wall across from the wall with the drive shaft.
• In terms of the volumetric metering of the dry, flour-like ingredients, the invention proposes that a metering device be located in the region of the charging opening that is equipped e.g., with sliding blades, which essentially comprises a cylindrical container with vertical axis for the flour, and this container is equipped with a volumetric metering mechanism at its bottom. The container has inside in its lower region an annular, funnel-like partition, and the point of a distribution cone extends through the partition's central, circular opening so that an annular passageway is free for the flour. The container has at the bottom a metering sieve above which beaters move during the rotation of the distribution cone, which is driven by means of a vertical central shaft by a motor, in order to transport the flour through the metering sieve and through the holes which are positioned equidistant to the rotational axis on the metering disk located beneath it. The metering disk is located on the bottom disk, which is connected to the cylindrical wall of the container and which has a hole in the region of the charging opening of the dough mixer attached beneath it, through which the flour falls from the metering holes at the rotating metering disk and through the charging opening into the chamber of the dough mixer.
• The present invention does not exclude the possibility that the dough mixer is fed from a metering device that has features other than those proposed by the invention, or from a device which charges with a pre-measured portion.
• One embodiment of the flour container and dough mixer described above is illustrated inFIGS. 5 and 6. This embodiment is capable of preparing individual portions of 130-260 g within 10-15 seconds, which is suitable for the automatic pizza making system of the present invention.
• FIG. 5 illustrates a section of adough mixer24 according to the invention during the charging phase and linked to ametering device80, showing a sectional view according to the plane of section I:I inFIG. 6, which plane runs through the axis of the drive shaft of themetering device80.
• FIG. 6 shows thedough mixer24 according to the invention and as shown inFIG. 5 together with ametering device80 in section according to the plane of section II-II inFIG. 5.
• Thedough mixer24 for preparing individual portions comprises ahousing81 with an inner chamber and a kneadingelement84,84c,84d, containing a chargingopening82aand a dischargingopening83a,81d, withcorresponding blades82,83. The essentially cylindrical chamber with horizontal axis is delimited by a level,circular surface81efrom which ashaft92aextends coaxially, by acircular surface81fcorresponding to the aforementioned but with a conical form projecting slightly into the chamber, by twocurved surfaces81awith a casing line equidistant from the chamber axis, by an upperlevel surface section81cthat essentially corresponds to the region of the chargingopening82a, and by a lowerlevel surface section81b, which is larger than the upper one and corresponds to the region of the dischargingopening81d,83a.
• The kneading element comprises anarm84 which is fastened on its front side at the end of thedrive shaft92athat extends into the chamber; at each of the ends ofarm84 apin84cis fastened having an axis running parallel to the rotational axis of thedrive shaft92a, and a freely turning84bsleeve84dwith a rounded, hemispherical or nose cone-shaped terminal area is placed on each ofpins84cby means of a recessed hole.Arm84 of the kneading element is fastened to driveshaft92a, off-center relative to the center line of the transverse-extending arm, such that twopins84cwithsleeves84dattached to it turn with varying radius about the rotational axis ofdrive shaft92a, which is driven by theelectric motor92 at varying rotational speeds and changing rotation directions.
• Charging opening82afor theintroduction94bof the flour-like ingredients in the upper region and dischargingopening83a,81dfor the individual portions of dough balls in the lower region, are provided with slidingblades82,83, which for example are moved82b,83bbypneumatic cylinders82c,83cwithout excluding the use of rotating blades and other drives.
• Liquid ingredients are charged via asingle hole93 or via specific holes for each of the liquid ingredients, which holes are conical and all preferably disposed on the disc-shapedwall91 in the region within the track ofsleeve84d, which turns with smaller radius aboutshaft84a.Same hole93 can be used for blowing in hot air to clean and/or sterilize the chamber androtating kneading elements84,84c,84d. The method for preparing dough with thedough mixer24 according to this invention, has essentially the following phases:
• • Charging94bwith flour- or dust-like ingredients,
  • Homogenization and aeration of the flour- and/or dust-like ingredients,
  • Charging93awith liquid ingredients,
  • Preparing the dough,
  • Rolling the dough thin,
  • Compacting and rolling the dough into balls
  • Discharging the individual dough portions
• Following production of a pre-programmed number of dough portions and based on the production intervals, the chamber of thedough mixer24 is cleaned and sterilized with hot air.
• • Charging94bwith flour-like and/or dust-like ingredients is by free fall through chargingopening82aequipped with slidingblades82, which is driven82bbypneumatic cylinder82c. The construction and operation of themetering device80, in accordance with the invention, with dischargingopening85e, corresponding to chargingopening82aof thedough mixer24 with which it is connected, will be explained later.
  • The flour-like and dust-like ingredients are homogenized and aerated by rotating kneadingelement84,84c,84dat a relatively high speed (approx. 2,500-3,000 rpm) that creates a favorable dispersion of the ingredients due to the special form of the chamber and kneading elements, wherein the particles of the dry ingredients are prepared for even absorption of the liquid ingredients following charging93a.
  • The dough mixture is prepared by rotating84akneadingelement84,84c,84dat a lower rotation speed (approx. 950-1,400 rpm); this phase is followed initially by the formation of little dough clumps, which are then rolled together by the repeated action of rotating84bsleeves84d.
  • The dough is then prepared by rotating kneadingelement84,84c,84dat an even lower rotation speed (approx. 850-920 rpm); especially in this phase, the dough is repeatedly and intensely rolled out and rolled thin by the turning84bsleeves84d, particularly at lowerlevel surface section81b. The formation of a compact, balled together dough mass follows at an even lower rotation speed (approx. 700-820 rpm), thus taking on the form of a “dough ball” at the end of this phase.
  • The “dough ball” is discharged by centrifugal force via the rotating kneading element and by gravity through dischargingopening83a, which is opened by activating83bblade83 by means ofpneumatic cylinder83c.
• During the various work stages, in particular during compacting, rolling out, and balling together the dough, it can be advantageous to make one or more changes inrotational direction84aof kneadingelement84,84c,84d. Liquid ingredients can be charged93amore or less in stages and while kneadingelement84,84c,84dis rotating. For cleaning and/or sterilization of the chamber by injecting hot air, the cool air ofmotor92 that drives92athe kneading element or the air that is diverted from the pneumatic system can be used, the air being heated prior to its injection into the chamber.
• Thevolumetric metering device80 for the dry flour-like ingredients according to the invention comprises acylindrical container85,85a,85bwith vertical axis, adistribution cone87 withbeaters87a,87brotating88acoaxially to the container axis, and ametering disk89 withmetering holes89aon the rim which form the volume units for creating a total portion offlour94 to be charged94binto thedough mixer24 in order to generate a single portion of dough.
• Cylindricalvertical wall85 is sealed withbottom plate85b, which provides aseating85cfor the bottom end of a vertically rotating88ashaft88 that is centrally seated85dincover plate85a. The upper end ofshaft88, which extends beyond thecover plate85a, is equipped with apulley88adriven by thebelt88bof amotor91 attached to the container.Shaft88 can naturally be driven in other ways and by other sources of power. Inside, in the lower region, the container is equipped with an annular, funnel-like partition86 for directingflour94 in the direction of the container axis. The upper region of adistribution cone87, which is connected to driveshaft88, extends through the central opening inpartition86 such that anannular duct86cresults for flour;beaters87bthat extend down from thecone86 and move closely abovepartition86cause flour94 to pass through94a.Partition86 andcone87 prevent variations in the fill level offlour94 and thus the weight abovepartition86 from having an affect on the metering mechanism disposed beneath. This mechanism comprisesmetering disk89 withholes89aon rim that rotates togetherdistribution cone87 and driveshaft88;individual holes89a, which are equidistant to the axis of rotation of the disk, represent with their volume the metering unit for creating the charging amount. Abovemetering disk89 is asieve90 equipped withducts90athrough which the flour is moved through at least onebeater87cwhich sticks out fromcone87, and turns withdrive shaft89, and moves abovesieve90. On the underside,metering disk89 lies on top ofbottom disk85bof the container.Bottom disk85bhas an outflow throughhole85ethat corresponds in diameter toholes89aonmetering disk89 or is of a greater diameter and in the region of the passage of these holes. Practice has shown that the construction described here allows volumetric metering that is independent of the fill level in the container, the moisture level and other physical properties of the contents, which metering is sufficiently constant and can be varied by one or more volume units that are determined byindividual holes89aonmetering disk89. This feature of themetering device80 is fundamental for achieving homogeneity in the individual dough portions, which requires charging with calibrated, homogeneous ingredients and attains this above all by assuring that the mixture does not put weight on the metering mechanism in asingle casing85,85a,85 which is fed via a relatively narrowannular duct86cand, affected by simultaneous mixing motions in the container region above thepartition86 and in the emptying region of the metering holes89aand at themetering disk89. Naturally, the amount offlour94, which moves throughannular duct86c, must be at least as great, preferably somewhat greater than the amount which is fed to thedough mixer24 for the purpose of maintaining the individual portion of dough.
• The present invention does not exclude the possibility of linking themetering device80 according to the invention to a dough mixer or another device that does not correspond to the dough mixer according to the invention.
• Pre-Former (FIGS. 7aThrough7c)
• FIGS. 7athrough7cillustrate various views of a pre-former28. The pre-former28 receives the “dough ball” discharged by centrifugal force via the rotating kneading element and by gravity through the dischargingopening83aof thedough mixer24, which is opened by activatingblade83bbypneumatic cylinder83b.
• The pre-former28 is the first step of a process of shaping the “dough ball” into a flat cake for pizza preparation.
• Referring toFIGS. 7athrough7c, the pre-former28 includes afunnel housing102 and adisc press104, which includes adisk plate106, apneumatic cylinder108 and aguide bar110.
• Opening113aat the top offunnel housing102 is positioned below discharge opening83a,81bof thedough mixer24. Thefunnel housing102 is fixedly connected to the underside of thehousing81 of thedough mixer24.
• The “dough ball” enters opening113a, falls by gravity and comes to rest within thefunnel housing102 in the vicinity of adischarge opening113bof thefunnel housing102, as shown inFIG. 7aby simulated “dough ball”114. Thedough ball114 is prevented from exiting thedischarge opening113bby alower press plate131 of thehot press30 which has been movably positioned in two dimensions against the bottom of thefunnel housing102 at thedischarge opening113b. The positioning of thelower press plate131 against the bottom of thefunnel housing102, covering thedischarge opening113b, is timed to coincide with theactivation83bof theblade83 which opens discharge opening81d,83aof thedough mixer24, which discharges the dough ball into the pre-former28.
• Thedisk plate106 is shaped as an inverted cup so that activation of thepneumatic cylinder108, lowering thedisk plate106 until contact with thelower press plate131 shapes thedough ball114 into a disc or puck. Thedisk plate106 and thelower press plate131 can be preheated to warm the dough ball113 during shaping to expedite dough baking later in the pizza making process.
• Hot Press (FIGS. 8aand8b)
• FIGS. 8aand8billustrate anupper press portion125 and alower press portion127 of thehot press30. Theupper press portion125 includes anupper press plate129 which is fixedly connected130 to structure of thepizza making system20. Thelower press portion127 includes alower press plate131, asupport plate132, abuffer plate133 and apneumatic cylinder134. Thelower press plate131 is fixedly connected to thesupport plate132 and separated therefrom by the one ormore buffer plates133. As thelower press plate131 is electrically heated to precook the dough during shaping, the one ormore buffer plates133 prevent the transfer of heat from thelower press plate131 to thesupport plate132 and thepneumatic cylinder134.
• Referring toFIG. 3, thelower press portion127 of thehot press30 is slidable in one dimension due to connection tolateral track136 andlateral conveyance system138. Thelateral conveyance system138 is pneumatically operated and programmed to slidably move thelower press portion127 under the pre-former28 with thepneumatic cylinder134 raising thelower press plate131 into contact with the underside of thefunnel housing102 to receive the dough ball discharged from thedough mixer24. After the pre-former28 shapes the dough ball into a disk, thelower press plate131 is lowered bypneumatic cylinder134 and thelateral conveyance system138 slides thelower press portion127 to the position shown inFIG. 3. Thepneumatic cylinder134 than raises thelower press plate131 against theupper press plate129 to shape the dough into flat cake for pizza preparation.
• Again, theupper press plate129 and thelower press plate131 are electrically heated to precook the dough during the shaping process.
• Dough Punching Device (FIGS. 9aand9b)
• FIGS. 9aand9billustrate a side elevation and top plan, respectfully, of thedough punching device32. Thedough punching device32 includes atoothed punching plate152, aslidable housing154, aslidable support bracket156 and two guide bars158.
• Referring toFIG. 3a, the dough punching device is shown in its non-operating position. The guide bars158 are fixedly supported to structure of thepizza making system20.FIG. 9bis a top plan of thedough punching device32 in this non-operating position. Theslidable support bracket156 is slidably attached to the guide bars158 and fixedly attached to theslidable housing154 which supports the two punchingplates152. A dough punching conveyance system (not shown) is programmed to timely operate thedough punching device32 after operation of the hot press30 (shaping the dough into flat cake).
• Upon completion of thehot press30 operation, shaping the dough into flat cake, thepneumatic cylinder134 lowers thelower press plate131 back to the position shown inFIG. 3a. At this time, flattened pizza dough rests upon thelower press plate131. The dough punching conveyance system initiates slidable movements of thedough punching device32 to an operable position shown inFIG. 3b. This operable position is also illustrated inFIG. 9a.
• Thepneumatic cylinder134 raises thelower press plate131 against a toothed underside of thepunching plate152 thereby dimpling the flattened pizza dough to facilitate uniform and expedited dough baking at a later stage of the automatic pizza making process.
• Thepneumatic cylinder134 then lowers thelower press plate131 to the position shown inFIG. 3aand thedough punching device32 returns to the non-operable position also illustrated inFIG. 3a.
• Referring toFIG. 1, apneumatic tilting stem160 is then actuated to lift a distal end of thelower press plate131 away from thesupport plate132, tilting thelower press plate131 about a hingedattachment point162 between thelower press plate131 and thesupport plate132 whereby the flattened, perforated pizza dough slides from thelower press plate131 to a conveyingtray36 positioned under thetomato sauce dispenser40.
• Summary of Dough Shaping and Dough Punching Process (FIGS. 15aThrough15f)—Includes Pre-Former, Hot Press and Dough Punching Device
• The entire dough shaping and punching process is summarized below in conjunction withFIGS. 15athrough15f:
• • FIG. 15a—thelower press portion127 is slidably positioned along thelateral track136 with thelower press plate131 raised to contact the underside of the pre-former28 to receive the dough ball and shape same into disc form.
  • FIG. 15b—thelower press portion127 is lowered away from the pre-former28 and transports the disc-shaped dough along thelateral track136 to a position for flattening under theupper press portion125.
  • FIG. 15c—thelower press plate131 is raised by thepneumatic cylinder134 into contact with theupper press plate129 to flatten the disc-shaped dough into flat cake for pizza preparation. The upper and thelower press plates129,131 are electrically heated to preheat the dough during the dough shaping to expedite the later baking of the pizza.
  • FIG. 15d—after flattening, thelower press plate131 is lowered and thedough punching device32 slides along the guide bars158 into an operating position under theupper press plate129.
  • FIG. 15e—thelower press plate131 is raised into contact with thetoothed punching plate152 thereby dimpling the flattened pizza dough to facilitate uniform and expeditious later baking of the pizza.
  • FIG. 15f—upon completion of dough shaping and punching, thepneumatic cylinder134 lowers thelower press plate131. The pneumatic tilting stem160 then raises a distal end of thelower press plate131 tiling same about a hingedattachment point160 connecting thelower press plate131 to thesupport plate132. The flattened and perforated pizza dough then slides from the lower press plate onto a conveying tray (not shown) under the tomato sauce dispenser40 (also not shown).
    Tray Conveying System (FIGS. 1 and 2)
• Referring toFIGS. 1 and 2, thetray conveyor system38 operates horizontally atlevel173 to transport one or more conveyingtrays36 atlevel172 from thetomato sauce dispenser40 throughcheese dispenser42,pepperoni dispenser44 andsausage dispenser46 to one of twoovens50,52.
• After dough shaping and punching is complete, and thelower press plate131 is tilted by the pneumatic tilting stem160 (as shown inFIG. 1), the receiving rack34 (tilted as shown inFIG. 1) receives the flattened and perforated dough released by the tiltedlower press plate131. Apneumatic cylinder171 raises a distal end of the receivingrack34, tilting the receiving rack about a hinged or pinnedattachment point170 between the receivingrack34 and structure of thepizza making system20 until the receiving rack is horizontal as illustrated byposition34aofFIG. 1. The conveyingtray36 is positioned within the receivingrack34 and is transported by thetray conveyor system38 away from the receivingrack34 and aligned precisely below the tomato sauce dispenser for liquid garnishment.
• After application by thetomato sauce dispenser40, thetray conveyor system38 transports the conveyingtray36 below thevarious dispensers42,44,46 stopping if programmed below one or more of thedispensers42,44,46 for respective topping application. Thetray conveyor system38 stops the conveyingtray36 at position174 (shown inFIG. 2) and directs the conveyingtray36 into one of theovens50,52.
• The conveyingtray36 remains with the pizza during baking in the oven and returns the pizza to position174 upon completion of baking. The cuttingdevice54 transports the prepared pizza fromposition174 to apackaging position175. The conveyingtray36 is transported back and into the receivingrack34 to receive the next flattened and perforated dough portion for pizza preparation.
• The automaticpizza making system20 as generally illustrated inFIGS. 1 through 4, can accommodate two conveyingtrays36 operating simultaneously. As one conveying tray is positioned in one of theovens50,52, a second conveying tray is transporting a flattened and perforated dough portion along the various preparation stations. As the second conveyingtray36 enters the vacant oven, the first conveyingtray36 removes a completed pizza to position174 and returns to the receivingrack34 to repeat the preparation process while the second conveyingtray36 remains in the other oven. Accordingly, the automaticpizza making system20 can accommodate the same number of conveyingtrays36 as ovens included in the respective system. Although the automaticpizza making system20 illustrated inFIGS. 1 through 4, includes two ovens and two conveying trays, the spirit of the present invention envisions various and multiple alternatives in oven and conveying tray design to accommodate the needs of any user.
• Tomato Sauce Dispenser (FIGS. 10aThrough10d)
• The object of the tomato sauce dispenser of the present invention is to meter and apply an even distribution of the tomato sauce on the flattened pizza dough, regardless of the inconsistency in homogeneity of some tomato sauces. The tomato sauce dispenser shall also facilitate easy cleaning and maintenance for good sanitation.
• To achieve this object, the tomato sauce dispenser of the present invention equips a nozzle and/or end of a tube through which the sauce supplied with all the motions that are necessary to achieve the even distribution on the sauce without using special conveying means for the sauce through the tube.
• The present invention uses a system of the spiral distribution, where the sauce falls onto the flattened pizza dough through a device that rotates about a vertical rotational axis. The rotating device has a threaded spindle that radially shifts the end of the tube or nozzle to dispense the sauce in a horizontal plane above the flattened pizza dough during rotation. Accordingly, the sauce is distributed in a spiral with constant gradient without moving the flattened pizza dough. In order to achieve a homogenous distribution, the speed of rotation (creating the spiral) is constant during the entire garnishing process. The spiral rotation preferably starts at the periphery of the flattened pizza dough and ends at the center. The number of revolutions of the device is increased in relation to the reduction of the radius of the spiral so that the sauce is always deposited onto the pizza at the same speed.
• The even and regular distribution in spiral-shape is guaranteed, if it is ensured that the spiral has a constant gradient, the garnishing product is dispensed without interruption and evenly, and in particular that the speed with which the garnishing product touches the basic product is uniform. As an alternative, the even distribution of the garnishing product can also be achieved by adjusting the volume (dispensed volume) in relation to the changed speed with which the garnishing product touches the basic product below.
• The tomato sauce dispenser includes a fixed basic frame with two horizontal plates; a friction ring or annular gear is mounted to the bottom plate in the region of a central bore, whereas on the top plate, a bushing is pivoted coaxially to this ring and this bore, which bushing is driven by an electric motor and permanently mounted to bearing plates for a threaded spindle; the rotation of this threaded spindle moves a carriage in the direction of the axis and to radially shift the end of the tube for supplying the sauce. The threaded spindle is driven via a friction disk which is in contact with the friction ring, or via an annular gear that engages the gear ring.
• By rotating the bushing and thus the bearing of the threaded spindle in one direction, the radial shifting of the carriage via the threaded spindle in one direction is achieved, for instance, outwardly to the rotational axis of the bushing, whereas the friction disk or toothed gear that is connected with the threaded spindle rolls off the friction ring or annular gear which is mounted to the stationary frame. Reversing the rotational direction of the bushing results in the shifting of the carriage from the area of the rotational axis of the bushing outward, that is, into the margin area of the flattened dough underneath.
• The flexible tube for supplying the sauce is routed freely through the rotating bushing. The tube is pivoted in the radially shiftable carriage so that the dispensed sauce can fall freely onto the pizza.
• The positioning of the end of the tube prevents the tube from twisting or becoming entangled while the various motions of the device are performed and also allows easy disassembly and replacement of the tube for cleaning and maintenance. The tube is preferably one piece using a peristaltic pump for sauce supply. The invention does not exclude employing a constant rotational speed for the end of the tube dispensing the sauce, whereas the decreased radius of the spiral would result in a reduced volume of sauce being delivered so that the sauce is evenly deposited onto the pizza. In order to limit the required cleaning and to maintain good sanitation, the tomato sauce dispenser allows easy exchange of the tube, using a single exchange part with a single tube coupling.
• FIG. 10aillustrates a top plan view of the tomato sauce dispenser according to the present invention.FIG. 10billustrates a front elevation section according to the plane II-II ofFIG. 10a, the plane II-II comprising a vertical axis of the tomato sauce dispenser shown inFIG. 10a.FIG. 10cillustrates a lateral view according to the plane III-III, partly in section, showing the carriage driven by the threaded spindle.FIG. 10dillustrates the top plan view shown inFIG. 10a, without the case, exposing a mounting for the threaded spindle and the carriage.
• Lateral carriers181 are mounted to aframe190 of a conveyor belt orconveyor chain191 byclamps181a, thecarriers181 supporting at their top a plate181bwithcentral bore181c.
• Abovecentral bore181cand coaxial to it, asecond plate183 is supported byarms182, thesecond plate183 being spaced parallel to the first plate181band centered, in which thesecond plate183 has abushing184 seated therein such that thebushing184 can be rotated183rviaball bearings183a. On an outer surface of thebushing184, a pulley or groove184ais supported for abelt188 that is used to transfer movement of apulley185aof anelectric motor185 to thebushing184. Twoarms183eare mounted to the bottom of thebushing184, whicharms183eextend downward and at the end of which verticalparallel bearing plates186 are mounted for a rotatable186rthreadedspindle186c, a leadingspindle186band a connectingelement186a. The threadedspindle186cis fitted with afriction disk186eat one of its ends that protrudes over the bearingplates186, whichfriction disk186erolls off afriction ring181fwith its rubber-coatedperiphery186f. Thefriction ring181fis mounted to the edge region of thecentral bore181cof the plate181bvia rings181e,181d. In order to ensure good contact between theperiphery186fof thefriction disk186eand thestationary friction ring181f, aball bearing186dis provided (seated at the same bearing plate186), whichball bearing186dprovides afriction disk186e, parallel and perpendicular to the rotational axis above, in order to form a thrust bearing on top of thefriction ring181f.
• In accordance withrotation183rof thebushing184, thearms183eand the bearingplates186 rotate together with the threadedspindle186c, thespindles186a,186band a movable189tcarriage189 connected thereto. Therotation183roccurs when thefriction disk186erolls on thestationary friction ring181f, thefriction ring181fbeing permanently mounted to the plate181b. The rollingfriction disk186ecausesrotation186rof the threadedspindle186c, therotation186rcausing movement189tin thecarriage189 due to an internally threadednut189bwithin thecarriage189 which engages the rotating threadedspindle186c. Thecarriage189 provides aguide part189c, theguide part189cincluding aseat189gwhich glides along the stationaryleading spindle186b. Therotation186rof the threadedspindle186ccauses thecarriage189 to move189talong the axis of the threadedspindle186c, whereas theguide part189cslides along the stationaryleading spindle186bto prevent thecarriage189 from twisting. This mechanism allows for movement189tof thecarriage189 to be linked torotational movement183r, resulting in aspiral193 distribution of the tomato sauce S with constant gradient. To ensure that the distribution of the sauce S on the flatteneddough192 is performed with uniform speed and independently of the distance ofend187aoftube187 from the rotational axis of thebushing184, and thus from the center of the flattened dough12 underneath, the number of revolutions ofmotor185 during movement189tof thecarriage189 from the outward area to the center area of the flatteneddough192 increases in relation to the decrease of the radius of thespiral193.
• Tomato Sauce S is supplied under pressure, which pressure can be generated by a peristaltic pump. The sauce S is routed axially via theflexible hose187 throughpassage184cof therotating bushing184, whichbushing184 has aninternal ball bearing184bto prevent friction with thetube187 duringrotation183r. Theend187aof thetube187 for dispensing the sauce S is pivoted onball bearing189d, which is mounted to thecarriage189. Theend187aof thetube187 is additionally routed through aring element189e, which is also mounted to thecarriage189.
• The present invention does not exclude that the threadedspindle186conly extends over an area that is slightly longer than the radius of the flatteneddough192 and that the threadedspindle186cis driven by a toothed gear, which derives motion from a gear ring, which is connected to stationary structure of thesystem20. Furthermore, the invention does not exclude that thetomato sauce dispenser40 is seated moveably so that it accompanies the flatteneddough192 while it is conveyed on conveyingtray36, without stopping the conveyingtray36, with thetomato sauce dispenser40 returning to its initial position after the garnishing process is complete.
• To achieve a uniform distribution, apart from the above described process which provides a change ofrotational speed183rwith a constant supply of sauce S, a process can be used that maintains a constantrotational speed183rwhile changing the supply of sauce S delivered in proportion to the change in the radius of the spiral (reducing the radius results in an increased supply capacity of the pump feeding the sauce).
• Furthermore, the present invention does not exclude that thebushing184 is seated within a single plate that covers the height of plate181band that has afriction ring181for an annular gear. In this alternative embodiment,axial passage184cof thebushing184 has a diameter that roughly corresponds to twice the movement distance of thecarriage189. The threadedspindle186ccan also be seated within thepassage184cof thebushing184. Thebushing184 can also be replaced by a circular plate that is rotatably183rseated on the stationary plate181band has a diametrically or simply radially arranged passage, within which or in the region of which the threadedspindle186cand thecarriage9 are seated.
• Cheese Dispenser/Sausage Dispenser (FIGS. 11aThrough11c)
• Cheese andsausage dispenser42,46 of the automaticpizza making system20 suitably applies any type of solid toppings, namely cheese, sausage, mushrooms pepperoni, etc., to the dough base prior to baking the pizza. Accordingly, cheese andsausage dispenser42,46 shown inFIGS. 11athrough11ccan also be used for thepepperoni dispenser44 of the automaticpizza making system20 shown inFIGS. 1 and 2. The cheese andsausage dispenser42,46 includes bulk portion control devices.
• Cheese andsausage dispenser42,46 has achamber202 for holding bulk solid topping, adoser204 attached to thechamber202 and amotorized stirring device206 attached to thedoser204 and used to feed thedoser204. Thedoser204 includes aslidable plate210 fitted between twofixed plates211,212. One of the fixedplates211 is attached to thechamber202 and the second fixedplate212 is positioned above the pizza. Theslidable plate210 includes a number ofopenings214 that are fed with a predetermined amount of solid topping from thechamber202. As theslidable plate210 is moved, theopenings215 of the fixed plate211 (attached to the chamber202) are closed and theopenings216 of the fixed plate212 (above the pizza) are opened, allowing portion of solid topping held within theopenings214 of theslidable plate210 to fall onto the pizza.
• Pepperoni Dispenser (FIGS. 12aThrough12d)
• Pepperoni dispenser44 of the automaticpizza making system20 suitably applies any type of solid toppings, namely cheese, sausage, mushrooms pepperoni, etc., to the dough base prior to baking the pizza. Accordingly,pepperoni dispenser44 as shown inFIGS. 12athrough12dcan also be used for thecheese dispenser42 and thesausage dispenser46 of the automaticpizza making system20 shown inFIGS. 1 and 2. Thepepperoni dispenser44 includes mono-dose portion control devices.
• The pepperoni dispenser44 (mono-dose portion device) includes a number ofstackable trays255 having a number ofdosing compartments257 used to hold asolid topping259. Thetrays255 are disposable and have registration features such as a dimple to maintain thetrays255 in alignment when stacked. Thetrays255 are preloaded, stacked and stored withtoppings259 and may be held in place by aretainer261, such as a string, tape or plastic wrap. Thetrays255 may be stored in a suitable modifiedatmosphere263 for preserving freshness of thesolid topping259.
• Thetoppings259 are dispensed from the stack oftrays255 as one is removed from the bottom of the stack. This is achieved by the use of the individually spaced dosing compartments257 that are maintained in a closed position by the bottom most tray in the stack. As eachtray255 is slidably removed265 from the bottom of the stack, the openings of the tray above it are opened to a pizza maintained below it and thesolid topping259 free fall267 to the pizza below.
• Ovens (FIGS. 13aThrough13f)
• As shown inFIGS. 1 through 4, and detailed inFIGS. 13athrough13d, the automaticpizza making system20 includes twoovens50,52 for baking the freshly madepizza1 transported to one of the twoovens50,52 by means ofovenproof plate302. Eachoven50,52 includes a heat retaining housing, apneumatic cylinder312, anopening304c, and a number ofheating elements307,308,310. The electric components of theovens50,52 are powered and controlled by a controller.
• As thepizza1 approaches one of theovens50,52, the controller activates thepneumatic cylinder312, which opens theopening304callowing thepizza1 to enter the selectedoven50,52. Once in theoven50,52, thepizza1 is baked until done in stages maintained by the controller. The cooking method is determined by many factors, including the intensity, frequency, and duration of heat applied by one or more of theheating elements307,308,310, and the distance between thepizza1 and theheating elements307,308,310. The intensity, frequency, and duration of the applied heat are set by the controller to achieve desired cooking qualities, such as surface browning, dough texture and crust crispness, each of which can be varied to accommodate consumer preferences.
• In one embodiment of the invention, the heating elements include two arrays of infrared heating devices, one set ofheating elements308 including rays in the visible and near-infrared range and the other set ofheating elements307 including rays in the far-infrared range. Infrared rays in the visible and near-infrared range with wavelengths of 0.75 μm to 3 μm propagate in accordance with the laws of optics during transmission. Specifically, these rays pass through water molecules, and therefore steam, with little or no absorption. Infrared rays in the far-infrared range with wavelengths of 6 μm to 1,000 μm, on the other hand, propagate through space in accordance with the laws of electromagnetics, and are absorbed and converted into radiant energy (i.e., heat) as they pass through matter.
• The invention employs a cooking method employing infrared wavelengths in the visible and near-infrared range concurrently or staggered with infrared wavelengths in the far-infrared range. When pizza cooking, the infrared rays with wavelengths in the visible and near-infrared range penetrate the pizza, in the presence of water (in the form of water vapor), to a depth of about 10 mm to 15 mm. Infrared rays in the far-infrared range penetrate about 0.5 mm to 0.8 mm.
• To maintain the depth of penetration of the infrared rays in the visible and near-infrared range, the outer layer of the pizza or thin cake should remain moist during cooking, as that would maintain a layer capable of absorbing all or most of the visible and near-infrared radiation, preventing the rays from failing to penetrate the pizza and excessively overheating the outer layer with respect to the rest of the dough. It is an object of the present invention, therefore, for infrared rays in the visible and near-infrared range to predominate initially, and for rays in the far-infrared range to be applied at the very end of the cooking process for surface browning. The cooking method of the present invention also calls for an initial heating cycle of a given duration, which raises the temperature of the thin cake very rapidly, quickly overcoming the thermal inertia of the dough and compensating for heat energy lost to the dispersal of fermentation gases, the evaporation of ethyl alcohol produced as the dough rises and the formation of water vapor.
• The cooking method then calls for a programmed series of heating cycles of decreasing duration with intervals between them that can be varied to prevent too much moisture from evaporating quickly from the thin cake, thereby sustaining deep penetration of the rays in the visible and near-infrared range for as long as possible. In a final stage the thin cake is heated for approximately the same amount of time as the initial heating period. This forms dextrins in the crust, which browns to form a thin textured layer, and imparts aroma and crispness through dextrinization and pyrolysis of starch.
• An oven built according to the invention and operating according to the disclosed cooking method can cook and brown a topped pizza in approximately 55 seconds. In addition, the thermal inertia of the housing of the oven is as low as possible, since its internal surfaces are shaped to reflect the rays onto the thin cake. In another embodiment of the invention, some or all of the radiation sources are mounted to move (with or without reflectors), thereby varying the distance from the source to the surface of the thin cake during the cooking process.
• The present invention could also include the use of a microwave generating magnetron, in addition to the sources of infrared rays. For fast cooking, a radiation or heat source could also be positioned below the pizza. In such an event, lamps emitting infrared rays in the far-infrared range could be used as a radiation source, and the thin cake could be supported on a perforated plate or grille such that at least some of the rays act directly on the thin cake while some heat the support which transfers heat to the thin cake by contact. If an induction unit is included in the oven, the plate is made of metal and provided with slits, or spiral or concentric circular openings, to transfer the heat by contact.
• The cooking method of the present invention may call for programming of the radiation and/or heat sources depending upon the toppings on the pizza to accordingly vary the heating times, the number and duration of heating cycles, the intensity (e.g., heating using a larger or smaller number of units), the distance between the sources and the pizza and/or the position or shape of the reflectors, if any.
• The oven of the present invention could be a bell-type oven having a stationary lower part and a moveable upper part to facilitate oven feeding using a mechanical transport means and to limit the cooking volume of the oven by completely shielding the radiation. However, the invention does not preclude application of the cooking method to other types of ovens, such as tunnel or muffle ovens. Also, the radiation sources, specifically the induction unit, may act independently of the infrared lamps or partially in conjunction with the radiation sources.
• FIG. 13aillustrates a sectional view ofovens50,52 along a vertical plane parallel to the longitudinal axis of the transport mechanism of thesystem20 and transverse to the lamps. The upper part of the oven is provided with lamps emitting infrared rays in the visible and near-infrared range and lamps emitting infrared rays in the far-infrared range. The upper part of the oven moves vertically, and is shown in a raised position with the transport plate and pizza in the cooking position. The stationary lower part of the oven is provided solely with lamps emitting infrared rays in the far-infrared range.
• FIG. 13billustrates a sectional view of the oven inFIG. 13aalong a vertical plane parallel to the arrangement of the lamps.
• FIG. 13cillustrates a sectional view of an oven built and equipped similar to the oven shown inFIG. 13b, the upper part additionally provided with a microwave emitting magnetron.
• FIG. 13dillustrates a sectional view of the oven inFIG. 13cin a closed position, and replacing the infrared lamps in the lower part with an induction unit.
• FIG. 13eillustrates a schematic diagram of the penetration of infrared rays and transmission of heat into the thin cake being cooked.
• FIG. 13fillustrates a simplified diagram of the cooking method according to the invention.
• Theovens50,52 are bell-type ovens attached to a knownhorizontal transport mechanism303 for aplate302 supporting thepizza1. Thelower part304 of theovens50,52 is mounted stationary on the frame of thetransport mechanism303 with apan306 at the bottom that can be removed for cleaning. Theframe305 of thelower part304 can be made from sheet metal with heat retaining internal surfaces, or theframe305 could be provided with reflectors. Thelower part304 of theovens50,52 can includelamps307 emitting infrared rays in the far-infrared range (FIGS. 13a,13b, and13c) or an induction unit310 (FIG. 13d). If thelower part304 includesinfrared lamps307, the lamps may be mounted stationary with respect to thepizza1, or mounted such that the distance from thepizza1 could be vertically adjusted during various cooking cycles. In such event, theplate302 is perforated or grille-shaped. If thelower part304 includes an induction unit310 (FIG. 13d), thetransport plate302 is metal and provided with slits, or spiral or concentric circular openings.
• Theupper part304aof theoven50,52 can be moved vertically304bby apneumatic cylinder312 anchored to astationary frame311 of the transport mechanism, whose piston acts upon a reinforced top304cof thebell305a. The inside of thebell305ais provided with an array oflamps307 emitting infrared rays in the far-infrared range and, above them,lamps308 emitting infrared rays in the visible and near-infrared range.
• The two sets oflamps307,308 may be mounted at a given fixed distance from thepizza1 being cooked, or one or both sets oflamps307,308 may be mounted so that the distance can be adjusted prior to or during the individual cooking cycles. Of course, the invention does not preclude usinglamps307,308 that are ring-shaped or shaped differently than as shown in the drawings.
• Lamps308 emitting infrared rays in the visible and near-infrared range are normally provided with internal reflectors. However, the invention does not preclude the use of special reflectors for one or both types of thelamps307,308. The reflectors can be mounted stationary so that they can be adjusted along with the lamps, and/or the reflectors may be mounted so that they can be adjusted and/or reshaped independently of the lamps, in order to vary the concentration of rays on thepizza1 being cooked.
• Theupper part304aof theoven50,52 may also be provided withmagnetrons309 to assist thelamps307,308 in overcoming the thermal inertia of the thin cake, and/or for cooking toppings with little or no moisture content, and/or decreasing the duration of the final surface browning cycle.
• In one embodiment of the invention, thelower part304 and theupper part304aof theoven50,52 are made from a thin material with low thermal resistance, having adouble wall305bproviding protection and safety, and thermal insulation having no significant influence on cooking time or energy consumption.
• The cooking method of the present invention is based on the specific penetration properties of infrared wavelengths in the visible and near-infrared range emitted bylamps308, and the infrared wavelengths in the far-infrared range emitted bylamps307. Referring now toFIG. 13e, in the presence of water molecules (and water vapor as well) infrared wavelengths in the visible and near-infrared range “Iv” penetrate “P” through the top surface “S” and into the dough “M” of the pizza or thin cake. These wavelengths are absorbed and converted into heat energy as they pass through (nontransparent) matter, transferring the heat “T” to the surrounding dough. By contrast, the infrared wavelengths in the far-infrared range “If” emitted by thelamps307 only penetrate to a depth of 0.4 mm to 0.8 mm. As a result, these wavelengths only act on the top surface “S” of the pizza being cooked.
• Referring now toFIG. 13f, to fully and quickly cook the pizza orthin cake1, the invention employs an initial heating cycle “A”, including exposure to infrared rays in both the “Iv” and “If” ranges, during which the mass of dough “M” and top surface “S” are preheated without excessively drying the top surface “S”. The initial cycle “A” is followed by a series of cycles “C” of varying but generally decreasing duration, during which infrared rays in the “Iv” and “If” ranges alternate with intervals “I” between the cycles to allow water molecules to diffuse into the top surface “S” in the form of steam, so that the “Iv” wavelengths can penetrate “P” into the dough “M”. Such penetration “P” naturally decreases as the moisture decreases and water vapor evaporates. The top surface “S” is browned during the extended final cycle “G”, using “Iv” and “If” wavelengths, since the “Iv” wavelengths now concentrate in the top surface “S” due to the decreasing moisture content in the top surface “S”, thereby reinforcing the “If” wavelengths to heat, dry, and brown the top surface “S”.
• The cooking method of the present invention also modulates the energy emitted in the form of “Iv” and “If” wavelengths for the various cycles “A”, “C” and “G” by differentiating the time the two types ofinfrared lamps307,308 are lit, and/or by varying the number of lamps lit, and/or by varying the position of the lit lamps in relation to the pizza orthin cake1, and/or by the position or shape of the reflectors.
• In addition, the cooking method could include the combined action of a microwave generator (magnetron)309 and/or aninduction unit310 in conjunction with theinfrared lamps307,308. Theadditional devices309,310 can emit energy during all or part of the cycles “A”, “C” and “G” described above, including all or part of the intervals “i” between the cycles, or solely during the intervals “i”.
• Automatic Cutting Device (FIGS. 14aThrough14f)
• The automatic cutting device of the present invention provides a simple, easy-to-clean cutting and transfer device that uses some of its cutting movements to transfer the pizza. The cutting device attaches a sheet that slides vertically by its own weight or by spring action to a side of a plate provided with blades. After cutting the pizza, the sheet holds the cut pizza in the cutting position as the plate that supports the pizza during cutting moves horizontally, dropping the pizza onto the top box of a stack of take-out boxes disposed below. Alternatively, the sheet assists the transfer of the pizza onto a take-out box to one side as the entire cutting device moves laterally, lifting the plate provided with blades once the pizza is placed on the box.
• The cutting device also provides blades that can easily be detached from the plate that holds them for replacement and cleaning, regardless of whether said blades are interchangeable with single-use blades or coated with a sheath or layer that can be removed easily at the end of a predetermined cutting cycle, thereby making the cutting device as hygienic as possible.
• For an embodiment of the present invention having mechanisms that move laterally, the cutting device is mounted to move in the direction of transfer of the pizza, providing a support for the take-out box or other packaging. To transfer the cut pizza from the cutting position to the packaging position, the plate provided with blades and vertically sliding sheet remains in the lowered, cutting position, or lifts slightly, as it moves toward the packaging position, dragging the pizza and sliding it off the transport plate onto the box positioned alongside. Once properly positioned over the box, the plate provided with blades lifts and moves back into position over the cutting area.
• A threaded rod and nut screw can advantageously be used to move the cutting device. The cutting mechanism is mounted on a carriage assembly that rolls on tracks. Rotating the threaded rod mounted on a stationary frame moves a nut screw attached to the carriage assembly. However, the invention does not rule out using a pneumatic or hydraulic cylinder, or mechanical means such as chains, belts or rackwork to move the cutting mechanism.
• Two embodiments of the pizza cutting and transfer device according to the present invention are illustrated in the accompanying drawings, which are not intended to limit the scope of the invention.
• FIG. 14aillustrates a front view of one embodiment of the automatic cutting and transfer device, showing a plate provided with interchangeable blades and a vertically sliding sheet in a raised position over the pizza, the pizza resting on a movable transport plate in a position above a stack of take-out boxes.
• FIG. 14billustrates a front view of the cutting and transfer device ofFIG. 1, showing the plate provided with interchangeable blades in a lowered, cutting position with a lower edge of the vertically sliding sheet resting on a top surface of the movable transport plate.
• FIG. 14cillustrates a front view of the cutting and transfer device ofFIG. 1, showing the transport plate after it has moved from the cutting position with the plate provided with blades in a lowered position and the pizza resting on the top take-out box in the stack of boxes underneath.
• FIG. 14dillustrates a front view of another embodiment of the automatic cutting and transfer device, where the cutting device transfers the pizza by dragging the pizza as it moves. The plate provided with stationary blades and a vertically sliding sheet is shown in a lowered, cutting position, while dotted lines show the cutting device in a raised position after moving to a packaging position.
• FIG. 14eillustrates a top view of the cutting and transfer device ofFIG. 14d.
• FIG. 14fis a left side view of the cutting and transfer device ofFIG. 14d.
• The cutting andtransfer device54 forpizza1 or focaccia according to the present invention includes acircular plate404, having fixed or interchangeablevertical blades404battached to the bottom thereof, and asheet404ethat slides vertically by its own weight or by spring action onstationary pins404gon the edge of theplate404. Thepins404gengage in correspondingvertical slots404fin the vertical slidingsheet404e.
• Ifinterchangeable blades404bare used (as shown inFIGS. 14a,14b,14c), theplate404 is provided with a series of radial cuts for insertion ofupper tabs404dof theinterchangeable blades404b, thetabs404dbeing provided with a hole into which small pins orcotters404care inserted transversely to hold thetabs404din place. Specifically, the fixed blades (as shown inFIGS. 14c,14d,14e) or interchangeable blades can be coated with a layer (e.g., applied by immersion, spraying on, or as a preformed sheath made from paper or plastic) that can be removed for easy cleaning of the blades. Theplate404, together with theblades404band vertical slidingsheet404e, can be moved vertically404aby apneumatic cylinder405 with arod405aand piston.
• The cutting device of the present invention is substantially identical for the two embodiments illustrated in the figures, whereby thetransport plate402 transfers thepizza1 to the take-outbox403 or other packaging. The slidingsheet404emounted laterally on theplate404 provided withblades404bperforms one of two functions. The slidingsheet404emay act simply as a projection to catch the edge of thepizza1 and hold it while thetransport plate402 moves402afrom the cutting position, leaving thepizza1 resting on the top take-out box in thestack403 of boxes disposed below the cutting position (FIG. 14c). Alternatively, the slidingsheet404emay act as a transfer means to push405bthepizza1, sliding thepizza1 off thetransport plate402 in the cutting position onto thebox403 in a packaging position (FIG. 14d). In the latter case, thetransfer plate402 may be replaced by a conveyor belt or other known transport means.
• In the embodiment (FIGS. 14d,14e,14f) where the slidingsheet404eacts as a transfer means (this embodiment is also shown inFIGS. 1, 2 and4), the cuttingdevice54 includes theplate404 provided withblades404band vertically slidingsheet404e, and includes acylinder405 with arod405aand piston mounted to move horizontally405bby aplate410 fastened to thecylinder405 and provided with fourwheels409 which roll on parallel,horizontal tracks407 mounted on astationary frame408. Anut screw407ais anchored to theplate410 and receives a threadedrod406bdriven406cby amotor406 provided with areduction unit406a, all forming a single piece with thestationary frame408. As the threadedrod406bis rotated in one direction or the other406c, thenut screw407a(along with theplate410 and thecutting device404,404b,405) moves405bbetween the cutting position (174 inFIG. 2) and the packaging position (175 inFIG. 2), where a take-outbox403 or other packaging is predisposed on a support403a.
• For theFIG. 14d,14e,14fembodiment, where the cutting mechanism moves horizontally, thepizza1 is cut and transferred to the take-outbox403 or other packaging in the following stages:
• • The cookedpizza1 on thetransport plate402 is moved into the cutting position by transfer means402b.
  • Thepizza1 is cut by lowering404atheplate404 provided withblades404b. Thesheet404erests on the top surface of thetransport plate402.
  • Theblades404blift almost imperceptibly from the surface of thetransport plate402. The slidingsheet404econtinues to rest on the surface by its own weight.
  • The threadedrod406brotates406c, moving405bthecutting device404,404b,405,405atoward the packaging position. Theblades404bandsheet404edrag thecut pizza1 off theplate402 onto thebox403 that rests on support403a.
  • Theplate404 andblades404blift404a.
  • Thecutting device404,404b,405,405amoves405bto the cutting position for the nextcooked pizza1.
• An advantage of the pizza cutting andtransfer device54 of the present invention is that it can be employed independently of the type of discontinuous or continuous mechanism used to transport thepizza1 into the cutting position (single plate, chain-driven series of plates, belt) or the method used to stock the packaging position (packaging disposed in stacks or individually).
• These and other advantages of the present invention will be apparent to those skilled in the art from the foregoing specification. Accordingly, it will be recognized by those skilled in the art that changes or modifications may be made to the above-described embodiments without departing from the broad inventive concepts of the invention. It should therefore be understood that this invention is not limited to the particular embodiments described herein, but is intended to include all changes and modifications that are within the scope and spirit of the invention.

Claims (22)

1. (canceled)

2. (canceled)

3. A method for automated and mechanized preparation of pizza, the method comprising the steps of:

a. receiving an order for a pizza, the order specifying topping requirements as selected from available offerings;

b. preparing an individual dough portion from flour and other component ingredients by:

i. charging a mixing region with flour-like or dust-like ingredients by free fall;

ii. homogenizing and aerating the flour-like or dust-like ingredients by rotating a kneading element at a relatively high speed;

iii. introducing liquid ingredients to the flour-like or dust-like ingredients;

iv. preparing a dough mixture by rotating the kneading element at a lower speed to form and roll together little dough clumps;

v. forming a single, compact, balled together dough mass by rotating the kneading element at a lowest speed; and

vi. discharging the single, balled together dough mass by centrifugal force via the rotating kneading element and by gravity;

c. shaping the dough portion to a flattened pizza base;

d. metering and applying toppings to the pizza base as received in the order;

e. cooking the pizza; and

f. providing the pizza.

4. The method ofclaim 3, wherein charging the mixing region is by free fall occurring through a charging opening in the mixing region equipped with a sliding door.

5. The method ofclaim 3, wherein the relatively high speed is between about 2,500 and 3,000 rpm.

6. The method ofclaim 3, wherein the lower speed is between about 950 and 1,400 rpm.

7. The method ofclaim 3, wherein the little dough clumps are formed and rolled together by repeated action of rotating sleeves of the kneading element.

8. The method ofclaim 3, wherein the lowest speed is between about 700 and 820 rpm.

9. The method ofclaim 3, wherein discharging the single, balled together dough mass occurs through a discharge opening in the mixing region equipped with a sliding door.

10. The method ofclaim 3, wherein the rotational direction of the kneading element changes one or more times during various method steps.

11. A method for automated and mechanized preparation of pizza, the method comprising the steps of:

a. receiving an order for a pizza, the order specifying topping requirements as selected from available offerings;

b. preparing an individual dough portion from flour and other component ingredients;

c. shaping the dough portion to a flattened pizza base by:

i. pressing a dough ball into a dough disc;

ii. pressing a dough disc into a pizza base; and

iii. dimpling the pizza base to facilitate a uniform and expedited cooking of the pizza base;

d. metering and applying toppings to the pizza base as received in the order;

e. cooking the pizza; and

f. providing the pizza.

12. The method ofclaim 11, wherein pressing a dough ball into a dough disc includes the steps of:

a. raising a lower press plate into contact with a preformer;

b. receiving a dough ball by gravity into the preformer; and

c. lowering a disc press of the preformer to form the dough disc by pressing the dough disc against the lower press plate.

13. The method ofclaim 11, wherein pressing a dough disc into a pizza base includes the steps of:

a. lowering a lower press plate away from a preformer while the lower press plate supports the dough disc;

b. horizontally moving the lower press plate to a position under an upper press plate of a dough shaping press; and

c. raising the lower press plate to form the pizza base by pressing against the upper press plate.

14. The method ofclaim 11, wherein dimpling the pizza base includes the steps of:

a. lowering a lower press plate away from an upper press plate of a dough shaping press, the lower press plate supporting the pizza base;

b. horizontally sliding a toothed punching plate to a position above the lower press plate;

c. raising the lower press plate to dimple the pizza base by pressing the pizza base against the toothed punching plate.

15. The method ofclaim 11, wherein the steps to shape the dough portion into a flattened pizza base (steps i., ii. and iii.) involves:

raising a lower press plate into contact with an open-bottomed housing;

receiving a dough ball onto the lower press plate;

lowering a disc press to form the dough disc by pressing the dough disc against the lower press plate;

lowering the lower press plate away from the housing while the lower press plate supports the dough disc;

horizontally moving the lower press plate to a position under an upper press plate;

raising the lower press plate to form the pizza base by pressing against the upper press plate;

lowering the lower press plate away from the upper press plate, the lower press plate supporting the pizza base;

horizontally sliding a toothed punching plate to a position above the lower press plate; and

raising the lower press plate to dimple the pizza base by pressing the pizza base against the toothed punching plate.

16. A method for automated and mechanized preparation of pizza, the method comprising the steps of:

a. receiving an order for a pizza, the order specifying topping requirements as selected from available offerings;

b. preparing an individual dough portion from flour and other component ingredients;

c. shaping the dough portion to a flattened pizza base;

d. metering and applying toppings to the pizza base as received in the order; wherein metering and applying liquid or cream-like components includes the steps of:

i. positioning the pizza base for garnishing;

ii. rotating a dispensing device about an axis perpendicular to the pizza base;

iii. moving the dispensing device radially relative to the perpendicular axis and parallel relative to the pizza base; and

iv. applying the liquid or cream-like component during steps (ii.) and (iii.), whereby the component is placed on the pizza base in a spiral.

e. cooking the pizza; and

f. providing the pizza.

17. The method ofclaim 16, wherein the pizza base is motionless during the application of liquid or cream-like components.

18. The method ofclaim 16, wherein the liquid or cream-like components are applied uniformly on the pizza base such that a time unit of dispensed volume of component remains constant, the uniform dispensing being achieved by altering the rotational speed of the dispensing device in relation to a changing radius of the spiral of component on the pizza base.

19. The method ofclaim 16, wherein the liquid or cream-like components are applied uniformly on the pizza base such that the rotational speed of the dispensing device remains constant and a time unit of dispensed volume of component changes in proportion to a changing radius of the spiral of component on the pizza base, wherein a reduction of the radius causes a decrease in the time unit of dispensed volume.

20. A method for automated and mechanized preparation of pizza, the method comprising the steps of:

a. receiving an order for a pizza, the order specifying topping requirements as selected from available offerings;

b. preparing an individual dough portion from flour and other component ingredients;

c. shaping the dough portion to a flattened pizza base;

d. metering and applying toppings to the pizza base as received in the order;

e. cooking the pizza, which involves;

i. at least one initial heating cycle;

ii. at least one intermediate heating cycle; and

iii. at least one final heating cycle, wherein

all cycles include use of infrared rays;

sources of infrared rays include infrared rays in the visible, the near-infrared, and the far-infrared range; and

a cooking effect of the sources of infrared rays in the visible and the near-infrared rays predominate during the initial heating cycle, while a cooking effect of the sources of infrared rays in the far-infrared range gradually counterbalance during subsequent heating cycles; and

f. providing the pizza.

21. The method ofclaim 20, wherein the initial heating cycle is longer than the longest intermediate heating cycle, and the final heating cycle is approximately a duration equal to the initial heating cycle.

22. The method ofclaim 20, wherein the infrared rays exist in a lower portion and in an upper portion of an oven and the sources of infrared rays in the lower portion operate during at least some portion of an interval between cycles of operation of the infrared rays in the upper portion.

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