~:~5~8~
The invention relates to improvements in apparatus for mixing liquids, and more particularly to improvements in apparatus which can be utilized with advanta~e for the making o carbonated or non-carbonated beverages. Still more particularlv, the invention relates to improvements in apparatus for intermixing two or more different liquids in such a way that the resultin~ mixture will contain predetermined percentages of intermixed liquids.
Many beverages can be made only by following a certain recipe. This applies, for example, to soft drinks wherein the main ingredient is water and the additional liquid or liauids can include extracts from nuts, syrups, fruit juices and/or others. Such beverages may but need not be carbonated. Accurate metering of various liquids prior to actual mixing is important because the purchasers of beverages expect a certain color and/or a certain flavor and/or a certain character and/or a certain viscosity and/or other desirable characteristics. Therefore, apparatus which are used to mix two or more different liquids (such liquids normally include a first liquid - often water -which is the main constituent of the beverage, and one or more additional liauids which normallv account for a relatively small percentage of the ultimate product) must be capable of mixing accurately metered quantities of various liquids. Moreover, the apparatus must be capable of thoroughly intermixing all ingredients in order to ensure that each and every portion of the mixture will exhibit identical characteristics, ~5;~8 . ~
particularly as concerns its color and flavor.
German Auslegeschrift No. 1 473 137 of (published discloses a mixing apparatus which is to be used in connection with the making of beverages and is equipped with devices for continuously metering each of two or more liquid ingredients which are being admitted into a collecting vessel. The apparatus comprises a container for each liquid, and each container is provided with an overflow. The containers receive the respective liquids in such quantities that the liquids overflow whenever the apparatus is in use. This ensures that each container confines a liquid column having a predétermined height so that the pressure at the lower end of the column is constant. The outlets at the lower ends of the containers are provided with flow restrictors which permit the respective liquids to escape from their containers at a selected rate~
and such li~uids are admitted into the collecting vessel.
Somewhat similar mixing apparatus are disclosed in German Auslegeschrift No. 24 19 353 of (puhlished and in ~erman Pat. No. 27 04 027 to (~ranted ).
The invention is embodied in an apparatus for making a mixture of a first liquid (e.g., water) with at least one additional liquid (such as syrup, fruit fuice or the like). The improved apparatus comprises at leas~ one first and at l~ast one additional metering device for the first liquid and for at least one additional liquid, respectively, and each metering device has at least one sealable inlet for admission of the respective liquid and at least one sealable outlet for evacuation of a metered ~uantity of the respective li~uid. The apparatus further comprises a liquid collecting vessel which serves to receive (directly or indirectly) liquids which are evacuated through the outlets of the metering devices.
The apparatus preferably further comprises means for re~ulating the capacity of the at least one additional metering device. Such regulating means can comprise means for monitoring the quantity of additional liquid in the at least one additional metering device and control means for sealing the at ; least one inlet of the at least one additional metering device when the at least one additional metering device ~` contains a selected quantity of additional liquid.
Alternatively, the regulating means can comprise at least one displacing element (such as a reciprocable piston) which is movably installed in a container ; (e.g., a cylinder) forming part of the at least one ~ additional metering device and including the respective at least one inlet and the respective at least one outlet.
The capacity of the at least one first metering device can be fixed (i.e.~ unchanging), and such at least one first meterin~ device can include a container having at least one opening which ~ermits the first liquid to overflow when the first liquid fills , .~.
-the container up to a predetermined level (of the opening or openings).
The at least one additional metering device can be installed in an upright or nearly upright position so that it includes a lower poxtion and an upper portionO The horizontal cross-sectional area of such at least one additional metering device preferably increases in a direction from the lower portion toward the upper portion.
The at least one irst metering device can include a plurality of containers for the first liquid, and each of these containers has at least one inlet.
The arrangement may be such that the at least one first metering device comprises two containers each of which has an inlet and an outlet; however, the inlet of one of these two containers can constitute the outlet of the other of these containers, i.e~, the containers can be connected in series.
It is also possible to connect the metering devices in series. In accordance with a presently preferred embodiment, the at least one outlet of the at least one first metering deviee is connected with a further inlet of the at least one additional metering device so that the first liquid which is evacuated from the at least one first metering device can enter the collecting vessel bv wa~ of the at least one additional metering devicer The collecting vessel can comprise at least one mixing tank for reception o liquids which are evacuated from the metering devices and at least one storage tan~ which receives intermixed Liquids (e.g., a beverage) from the at least one mixing tank.
The apparatus can comprise a plurality of additional metering devices for different additional liquids. The upper portion of each additional metering device can constitute a gas-filled plenum chamber, and such plenum chambers can be com~unicatively connected to each other. The additional metering devices can be positioned adjacent one another and can be parallel or nearly parallel to each other.
The apparatus can further comprise a bypass which connects the at least one first metering device with the collecting vessel, This renders it possible to convey a first portion of a metered quantity of first liquid from the at least one first metering device directly into the collecting vessel by way of the ~ypass and to convey the remaining portion of the metered quantity of the firs~ liquid into the collecting vessel by way of the a~ least one additional metering device.
The apparatus can also comprise at least one source of compressed gaseous fluid ~such as carbon dioxide gas), liquid sources connected with the respective metering devices and means for connecting the at least one source with the liquid sources in order to maintain the liquids in the meterin~ devices at an elevated pressure. The liquid sources include a source of first liquid and the connecting means can include maans for connecting the source of compressed gaseous fluid with the collecting vessel and with the ' source of first liquid. Such apparatus can further comprise means for establishing a path :Eor the circulation of compressed gaseous fluid through the collecting vessel and through:the source of first liquid. The connecting means is or can be desi~ned in such a way that it establishes a path for unidirectional flow of compressed gaseous fluid from the source of compressed gaseous fluid to each additional metering device, i.e., compressed gas need not always be circulated through the at least one first metering device as well as through the additional metering device or devices.
In accordance with a presently preferred embodiment, the apparatus comprises a source of first liquid which is connected to the at least one inlet of the at least one first metering device, mean~ for conveying predetermined quantities of first liquid : from the source to the at least one first metering device, a sealable bypass which connects the at least one inlet of the first metering device with the source for return flow of first liquid into the source, means for sealing the at least one inlet of the at least one first metering device when the latter is filled with first liquid, and means for~circulating the first liquid along an endless path extending through the : bypass and the source upon sealing of the at least one inlet of the at least one first metering device. Such apparatus can fuxther comprise means for impregnating the first liquid with a gaseous fluid in the at least one inlet of the at least one first metering device 2~
upstream of the bvpass. The impregnating means can comprise a source of carbon dioxide gas and at least one nozzle which is connected with the source of carbon dioxide gas and is installed in the at least one inlet of the at least one firs' metering devic:e.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims~ The improved apparatus itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof/ will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawing.
FIG. 1 is a schematic elevational view of a mixing apparatus which embodies one orm of the invention and comprises a total of four metering devices;
FIGo 2 is a similar schematic elevational view of a portion of a second apparatus which includes a modified metering device for the first liquid; and FI~. 3 is a similar schematic elevational view of a portion of a third apparatus with different regulating means for the capacity of the illustrated additional metering device.
Referring first to FIG. 1~ there i5 shown an apparatus for making a mixture of four liquids 2, 21 22 and 23 which are respectively stored in and supplied by sources 1, 17, 18, 19 in the form of tanks or the like. The ultimate product is a beverage 37 which is impregnated with a gaseous fluid (such as carbon 2~
dioxide gas) and is confined in a storage tank 33 ; forming part of a collecting vessel which further includes a mixing tank 32. The source 1 contains a supply of that liquid ~in many instances water) which constitutes the major percentage of the beverage 37. The source 1 receives fresh liquid 2 from a larger source (e.g., a water tap) through a supply conduit 3 ~ which contains a shutoff valve 4. The discharge end ; 3a of the supply conduit 3 constitutes a nozzle with orifices which discharge sprays of water into a plenum chamber 6 constituted by the upper portion of the source 1 and containing a supply of compressed gaseous fluicl.
The plenum chamber 6 receives compressed gaseous fluid through a supply conduit 7, and a further conduit 8 is provided to provide a path for evacuation of compressed gaseous fluid from the plenum chamber 6.
` The conduit 8 contains one or more valves, e.g., a shutoff valve and a pressure regulating or relief valve.
The feature that the discharge end 3a of the supply conduit 3 delivers sprays of fresh liquid 2 into the plenum chamber 6 ensures that the admitted liquid is at least partially relieved of air and is impregnated with compressed gaseous fluid.
The apparatus comprises a first metering device 12 for liquid 2, and this metering device has an inlet 9 (here shown as a conduit having a receiving end in communication with the lower end of the source 1) which is sealable b~ a valve 11 and supplies the first uid 2. The upper portion of the metering device 12 30 i5 provided with an overflow opening 13 for admission ~5~ 3 of surplus liquid into a return conduit 14 which discharges into the source 1 at a level a})ove the plenum chamber 6. The metering device 12 contains a predetermined quantity of first liquid 2 when its outlet 16 is sealed b~ a valve 16a and the liquid fills the device 12 to the level of the overflow opening 13.
The a~paratus of FIG. 1 further comprises three additional metering devices 24, 26, 27 for the additional liquids 21, 22, 23, respectively. The inlets 17c, 18c, l9c of the metering devices 24, 26, 27 are connected to the respective sources 17, 18, 19 of additional liquids 21, 22 and 23. The inlets 17c, 18c, l9c are respectively sealable by valves 17a, 18a, l9a and these inlets (each of which is shown in the form of arl elongated conduit) further comprise adjustable flow restrictors 17b, 18b, l9b, respectively.
The additional metering devices 24, 26, 27 comprisa upright containers which are adjacent and parallel to each other. Each of these additional me~ering devices i5 associated with a regulating unit which can select the capacity of their containers.
The regulating units comprise monitoring means in the form of liquid level indicators 28 and sealing or control devices 58 (one shown in FIG. 2) which control the respective shutoff valves 17a, 17b, 17c to terminate the admission of additional liquids 21, 22, 23 when the respective level indicators 28 show that the associated additional metering devices contain predetermined ~uantities of liquids~
The additional metering devices 2~, 26, 27 have discrete outlets 29 which are sealable by valves 31 and the discharge ends of which are connected to the mixing tank 32. The outlet 16 of the metering device 12 for the liquid 2 does not discharge directly into the mixing tank 32 and/or into the storage tank 33 of the two-piece collecting vessel but rather into a common plenum chamber 38 at the tops of the additional metering devices 24, 26 and 27. Thus, the first liquid 2 can enter the mixing tank 32 by flowing through the cOntainers of the additional metering devices 24, 26, 27 so that these containers are automatically rinsed with first liquid (such as water) in res~onse to openin~
of the valves 16a and 31. The tank 32 ensures that the liquids which are free to leave the container of the metering device 12 and the container or containers of one or more additional metering devices (24, 26 and/or 27) are intimately or reasonably intimately intermixed even before they enter the storage tank 33 wherein the mixing can continue in order to ensure highly satisfactory homogenization o the beverage which is to be admitted into cans, bottles or other suitable receptacles in a manner not forming part of the present invention. Reference may be had, for example, to commonly owned copending patent application Serial No.
07/56~,254 of Manfred Mette filed Auyust 15, 1990 for "Method of and apparatus for filling containers with liquids", now U.S. Pat. No. granted Intimate mixing of two or more liquids in the s~orage tank 33 is enhanced by the provision of a 2~35~
liquid circulatin~ unit includln~ a conduit 34 extending ~etween two spaced apart portions of the tan]; 33 and a pump 36 or any other suitable fluid flow machine which causes a stream o the mixture of two or more liquids to flow through the conduit 34.
The maximum capacity of the additional metering device 24 can but need not match that of the metering device 26 and/or 27. The feature that the outlet 16 of the metering device 12 can discharge, first liquid 2 into the common plenum chamber 38 of the metering devices 24, 26, 27 not only ensures adequate rinsing of the containers of additional meterin~ devices but also ensures that the first liquid 2 is again impregnated with gaseous fluid before it reaches the mixing tank 32. In addition, such mode of conveying metered quantities of first liquid 2 into the tank 32 ensuLes that a thorough mixing of the liquid 2 with the liquid 21, 22 and/or 23 will take place even before the thus obtained mixture reaches the mixing tank 32. The metered quantity of first liquid 2 which flows through the containers of the additional metering devices 24, 26, 27 ensures that all traces of additional liquids are expelled from the respsctive containers when the apparatus is in the process of admittin~ two or more liquids into the tank 32. Thus, the liauids are mixed in several successive stages, first in the containers of the additional metering devices 24, 26 and 27, thereu~on in the mixing tank 32 and finall~,t in the storage tank 33. The first mixin~ stage begins as soon as the valves 16a and 31 are opsned, i.e., as soon as the first liquid 2 is free to leave the metering device 12.
A conduit 39 is ~rovided to connect the plenum chamber in the upper part of the storage tank 33 with the common plenum chamber 38 of the additional metering devices 24, 26 and 27.
The means for withdrawing the beverage 37 from the storage tank 33 includes a conduit 42 which contains a pump 4I and delivers the beverage into a secondary mixing vessel or aftermixer 43. The conduit 42 further contains a device 44 which serves to impregnate the stream of heverage 37 with a compressed gaseous fluid, such as carbon dioxide gas. The illustrated impregnating device 44 includes a source of compressed gaseous fluid (this source includes a tank, not shown, and conduits 47, 46 which receive a stream of gaseous fluid from the source) and an injector nozzle in the conduit 42 at the discharge end of the conduit 46. The lat~er contains a preferably adjustable flow restrictor, and the conduit 47 contains one or more valves, e.g., a shutoff valve and a pressure regulating or relief valve. The conduit 47 further serves to admit compressed gaseous fluid into a plenum chamber 48 constituting the upper portion of the aftermixer 43. An evacuating conduit 49, which is equipped with a valve 49a (e.g., a combined shutoff and flow re~ulating valve) serves to deliver the repeatedly intermixed li~uids to a decanting station, e.g., to a machine which admits the beverage into bottles, cans or other suitahle receptacles.
The ccnduit 49 can deliver one or more streams of ~ gas-im~regnated (normall~ carbonated) beverage 37 : to the tank of a bottle or can filling machine or to the discrete filling units of such machine.
The plenum chamber in the upper ~art of the tank 33 receives com~ressed gaseous fluid from the plenum chamber 48 ~f the aftermixer 43 by way of a supplY cond~it 51. The conduit 7 receives compressed gaseous fluid from the plenum chamber of the tank 33 and delivers compressed gaseous fluid to the plenum chamber 6 of the source 1. A conduit 52 branches off the conduit 7 and delivers compressed gaseous fluid to ; the plenum cham~ers in the upper portions of the additional li~uid sources 17, 18 and 19~ A continuous stream of compressed gaseous fluid can flow from the conduit 47, through the ~lenum chamber a8, conduit 51, plenum chamber of the tank 33, conduit 7, plenum chamber 6 and evacuating conduit 8. The flow of compressed gaseous fluid into the plenum chambers of the sources 17, 18 and l9 is unidirectional. A certain percenta~e of such fluid impregnates the supplies of liauids in the sources 17, 18, l9 and is evacuated via inlets 17c, 18c, l9c, the containers of the additional metering de~ices 24, 26, 27 and the outlets 29 into the mixing ~ank 32.
The stream of compressed gaseous fluid which flows from the conduit 47 toward and into the conduit 8 flows counter to the direction of flow of first liquid 2 to thus ensure expulsion o a high percentage :' ~
.
2~5~8.~
of air and impregnation of the liquid 2 with compressed gaseous fluid, The conduit 39 establishes communication between the common plenum chamber 38 of the additional metering devices 24~ 26, 27 on the one hand r and the plenum chamber in the tank 33 on the other hand. The stream of gaseous fluid which flows from the tank 33 into the plenum chamber 38 is not circulated. An advantage of the absence of circulation of compressed gaseous fluid through the sources 17, 18, 19 of _D additional fluids and the additional metering devices 24, 26, 27 is that the gaseous fluid cannot evacuate volatile aromatic substances which are often contained in the additional liquids.
The apparatus of FIG. l further comprises a bvpass conduit 53 which conn~cts the inlet 9 with the source 1 at a level beneath the plenum chamher 6 and contains a shutoff valve 53a. When the valve 53a is open and the pum~ 34 is on, a stream of first liquid 2 is ree to circulate from the ~ottom of the 'D source l, through the lower portion of the inlet 9, through the by~ass S3 and into the upper portion of the supplv of irst liquid 2 in the source 1. The lower ~ortion of the inlet 9 (namely the portion which is located upstream of the bypass 53) contains the injector nozzle 56 of an additional impregnating device which is, or which can be, identical with the impregnating device 44 having a nozzle in the conduit 42. The im~regnating device including the injector nozzle 56 ensures the expulsion of at least some air from the strea~ of first liquid 2 in the inlet g and Z~5~4~
first liquid 2, the valve 53a in the bypass 53 is closed (either hy hand or by automatic operating means, not shown). The pump 34 then supplies a stream of first li~uid 2 from the lower portion of the source 1, through the inlet 9 and its nozzle 56, through the open valve 11 and into the container of the metering device 12. The valve 53a in the bypass 53 is or can be opened again when the container of the metering device 12 ls nearly filled so that the rate of admission of first liquid into the device 12 is decelerated. The valve 11 in the inlet 9 is closed when the first liouid 2 begins to overflow the container of the metering device 12 via opening 13 to flow back into the source 1 via conduit 14. The motor for the pump 34 is on so that this pump causes a continuous stream of first liquid to flow from the lower portion of the source 1, through the inlet 9 and bypass 53 and back into the upper portion of the supply of liquid 2 in the source 1.
Such continuous circulation of first liquid 2 is desirable and advantageous hecause the circulating liouid stream is impregnated with compressed gaseous fluid during flow through the nozzle 56. At the same time, the then open valve 4 permits a stream of fresh liquid 2 to flow from the main source of such liquid into the plenum chamber 6 via conduit 3 and its spray nozzle 3a.
The containers of the additional metering devices 24, 26 and 27 receive, or can receive, metered quantities of the respective additional fluids 21, 22 and 23 from the corresponding sources 17, 18 and 19 s~
while the container of the flrst metering device 12 receives first liquid 2 from the source 1. All that is necessary is to open the valves 17a, 18a and l9a so that the sources 17 t 18 and 19 can discharge streams of the respective additional liquids into the containers of the associated additional metering devices 24, 26 and 27. The flow restrictors 17b, 18b, 19b can be actuated to reduce the rate of flow of li~uids 21, 22, 23 when the containers of the corres~onding metering devices 24, 26 and 27 are nearly filled. This renders it possible to select the levels of the columns of liquids 21, 22, 23 in the respective meterin~ devices 24~ 26 and 27 with a high degree of accuracy. I'he sealing or control devices 58 of regulating means for the ca~acities of containers of the metering devices 23, 24 and 26 are caused to close the respective valves 17~, 18a and l9a when the control device~ 58 receiye signals (from the corresponding li~uid level indicators 28) that the columns of liquids 21, 22, 23 in the containers of the metering devices 24, 26, 27 have risen to preselected levelsO
The next step involves opening of the valve 16a in the cutlet 16 of the first metering device 12 and the valves 31 in the outlets 29 of the additional ; metering devices 23, 24 and 26. This opens three paths for the flow of first Ii~uid 2 and of the additional liquids 21, 22, 23 from the respective metering devices into the mixing tank 32 of the collecting vessel which further includes the storage tan~. 33. The previouslv metered quantities of liquids 21, 22, 23 can flow from :, :~ .
2C~5;~ 8?- 9 the containers of the metering devices 24, 26 and 27 directly into the mixing vessel 33, and the pxeviously metered quantity of first liquid 2 enters the tank 32 by flowin~ first through the containers of the additional metering devices 24, 26 and 27. As mentioned above, this ensures thorough intermixing of the first liquid 2 with the liquids 21, 22 and 23 before these liquids reach the mixing tank 32. In addition, the containers of the metering devices 24, 10 26 and 27 are automatically and thoroughly rinsed with the first liquid 2 so that the batch or charge of liquids 2, 21, 22 and 23 which is permitted to enter the .storage tank 33 through the mixing tank 32 contains predetermined percenta~es of each of these liquids~ The valves 16a and 31 are closed as soon as the evacuation of the contents of containers o~ all fQur metering devices into the collecting vessel, 32, 33 is completed, and the apparatus is then ready ko proceed with admission of fresh metered quantities 20 of liquids 2, 21, 22 and 23 into the containers of the respective metering devices 12j 24, 26 and 27.
FI~,. 2 shows a portion of a modified liquid mixing apparatus. All such parts of this apparatus which are identical with or clearly analogous to corresponding parts of the apparatus of FI~,. 1 are denoted by similar reference characters~
The first metering device comprises two containers 12 and 61 which are connected in series.
Thus, the inlet of the container 61 is constituted 30 by the condui~ 9 which is connected to the source 1 2~5~ q.3 (not shown) of first liquid 2 and can be sealed bv the valve 11. The outlet at the upper end of the container 61 constitutes one inlet of the container 12 which has an overflow opening 13 leading to a return conduit 14 and which further comprises an outlet 16 sealable by a valve 16a and serving to discharge first liquid from the container 12 into the plenum chamber 38 at the upper end of the additional metering device 24. The valve 17a in the inlet 17c is controlled by a regulating means including the sealing or control device S8 and the liquid level indicator 28. The outlet of the container 61 is sealable bv a valve 62, and this outlet serves to admit the additional liquid 121) and some of the first liauid (namely that which fills the container 12) into the mixing tank 32. A bypass conduit 59 establishes . communication between the plenum chamber 38 and (through the tank 32) with the plenum chamber in the u~per portion of the storage tank 33 (not shown in FIG. 2).
The first metering device including the containers 12 and 61 is filled when the first li~uid overflows via opening 13 into the return conduit 14.
When the valves 16a and 31 are open but the valve 62 is closed, the tank 32 receives the contents of the container 12 and the contents of the container of the additional metering device 24. The contents of the container 12 flo~l into the plenum chamber 38 and a hi~h percentage of such contents bypasses the container of the metering device 24 in that the first :.
. , ~5~8~
liquid flows into the tank 32 through the bypass conduit 59 rather than through the outlet 29 and valve 31. Such mode of admitting liquids into the tank 32 is often desirable and advantageous, for example, when the tank 32 should not contain (even temporarily) a relatively high ~ercentage of the liouid ~21) which fills the container of the additional metering device 24. Thus, the tank 32 receives a substantial amount of first liquid 2 (from the container 12 by wav of the conduit 59~ as soon as the valves 16a and 31 are opened. It has been found that certain liquids are more li~ely to form a homogeneous mixture if all ingredients of the mixture enter the tank 32 at the same time or ~racticallv simultaneouslv so that the percentage of the additional liquid or liquids in the tank 32 does not unduly increase, even for a short intérval of time following opening of the valve 31 The valve 62 will be opened simultaneously with the valves 16a and 31 if the beverage in the storage tank of the collecting ve~el including the mixing tank 32 is to contain a higher percentage of first liquid 2. The container 61 and the valve 62 enhance the flexibility and versatility of the mixing ; apparatus and render it possible to alter the metered quantity of first liquid without the need for adjustabilitv of the capacity or volume of the container 12 and/or 61.
The container 61 can be said to constitute a hypass for the first liquid 2, i.e., the liquid which fills the container 61 can be discharged into the 2~ 37. ~
mixing tank 32 without being compelled to flow first through the container of the additional meterin~
device 24. The bypass which is established by the container 61 is a total bypass hecause none of the first liquid which fills this container must flow through the meterin~ device 24. The conduit 59 can be called a partial bypass because some of the first liquid which fills the container 12 is free to enter the container of the metering device 24 when the valve 16a in the outlet 16 is actuated to permit the first liquid to escape from the container 12. The concentration of second liquid 21 which is heing discharged from the container o the metering dev.ice 24 in response to opening of the valve 31 is even less likely to rise (or to rise to an undesirable extent) in the tank 32 (.even for a short interval of time) if the valve 62 is opened simultaneously with (or, if necessary, ahead of) the valve 31 in the outlet 29 of the metering device : 24.
The supply of first liquid 2 in the container 61 is renewed at frequent intervals even if the valve 62 rema.ins closed while the valves 16a and 31 are open.
This is due to the fact that the inlet 9 is not directly connected to the container 12, i.e., the container 12 can rec~ive first liquid only from the container 61.
In other words, the supply of li~uid 2 in the container 61 is renewed prior to start of each metering cycle because each cycle involves the admission of first liquid into the container 12 bv way of the container ~l.
~he apparatus which includes the structure of I'r~
; FIG. 2 can comprise two or more additional metering devices, e.g., the metering devices 2~, 26 and 27 of FIG. 1.
FIG. 3 shows a portion of a third mixing apparatus, The reference character 63 denotes the metering device for the first liquid 2. The upper end of the container of the metering device 63 is provided with an opening which permits surplus liquid to overflow into a return conduit corresponding to the conduit 14 in the apparatus of FIG. 1. The inlet 66 of FIG. 3 corresponds to the inlet 9 and is sealable by a suitable valve 67. The container of the meterin~
; device 63 comprises an outlet 68 which is sealable by a valve 69 and can discharge a metered quantity of first liquid into the cylindrical container of an additional metering device 71r e.g., a metering device for the li~uid 21, 22 or 23.
The reference character 74 denotes a source of additional liquid 81, and the supply of such li~uid is located at a level below a plenum chamber 78.
The supplv of additional liquid 81 in the source 74 can be replenished from a main source by way of a supply conduit 79 which contains a suitable shutoff valve and/or a regulating valve. A conduit 76 for compressed gaseous fluid contains a shutoff valve or a re~ulating valve 77 and connects the plenum chamber 78 in the source 74 with the interior of the cylindrical container of the additional metering device 71.
The rate of admission of second liquid 81 into ; 30 the source 74 is preferably such that the upper surface 2~
of the supply of liquid 81 therein is maintained at or close to a selected level.
The means for regulating the capacity or volume of the container of the additional metering device 71 includes a mobile displacing element here shown as a piston or plunger 82 which is reciprocable in the cylindrical container of the meterin~ device 71 in order to alter the volume of that poxtion of the container which can receive second liquid 81 by way of the inlet 72 and valve 73. The outlet 83 of the cylindrical vessel of the meterlng device 71 is sealable b~ a valve 84 which can admit a mixture of liquids 2 and 81 into the mixing tank or directly into the storage tank of the beverage collecting vessel (not shown in FIG. 3).
The operation of the apparatus which includes the structure of FIG. 3 i5 as follows:
The valve 67 is o~ened so that the inlet 66 can supply a stream of first liquid 2 from the source 1 (not shown in FIG. 3) until the first liquid begins to overflow into the return conduit 14. At the same t~ne, the o~erator or an automatic programming : unit opens the valve 73 so that the inlet 72 can admit a stream of second li¢uid 81 from the source 74 into the cylindrical container of the additional meterin~
device 71 abo~e the piston 82. Since the container of : the metering device 71 and the source 74 are connected to each other in a manner known as communicating vessels, the additional li~uid 81 which flows from the source 74 into the cylindrical container of the metering - ~4 -8~i~
device 71 rises in the conduit 76 to a level corresponding to the level of the upper surface of the supply of liauid 81 in the source 74. The valve 73 is closed when the upper end of the column of liquid 81 in the conduit 76 is at the level of the upper ~nd of the body of liquid in the source 74. The valves 69 and 84 are thereupon opened in order to initiate the admission of metered quantities of first liquid 2 and additional liquid 81 into the collecting vessel.
An advantage of the apparatus which embodies the structure of FIG. 3 is that it can deliver to the collecting vessel accurately metered quantities of two or more liquids. This holds particularly true for the additional li~uid 81 because the inner diameter of the conduit 76 is or can be very small so that minor deviations between the level of the upper end of the body of liquid 81 in the source 74 and the level of the upper end of the small-diameter column of liquid 81 in the conduit 76 cannot affect the accuracy of the metering action of the device 71 to any appreciable extent. This holds true even if the level of the upper end of the body of liquid 81 in the source 74 happens to fluctuate, The valve 77 is preferably closed subsequent to admission of additional liquid 81 into the lower portion of the conduit 76 and not later than on opening of the valves 59 and 84. This ensures that the first liquid which flows from the metering device 63 in response to o~enin~ of the valve 69 cannot expel additional liquid 81 from the upper portion of the 2 ~3 ~
cylindrical container of the metering clevice 71, through the conduit 76 and back into the source 74.
The apparatus which includes the structure of FIG. 3 can also comprise two or more additional metering device~, e.g., a total of three additional metering devices as in the apparatus of FIG. 1.
The apparatus of the present invention differs from the previously de~cribed conventional apparatus in that it is designed to supply to the collecting vessel a series of discrete charges or batches of two or more li~uids. Thus, instead of employing metering devices which are designed to permit continuous flow of the respective liquids into a collecting vessel, the improved apparatus accumulates a discrete batch or charge or metered quantity of each liquid in the respective metering device, and the charges are thereupon caused ~r permitted to leave the respective meterin~ devices and to enter the collectin~ vessel. It has been found that the improved apparatus is more reliable than conventional (continuous-flow) apparatus because each individual ; metered quantity can be selected with a high degree of accuracy, and such accurately metered quantities of two or more liquids are thereupon admitted or compelled to flow into the collecting vessel.
Another important advantage of the improved apparatus is its simplicity and compactness. Thus, the number of pumps in the apparatus can be re~uced to a minimum, and the pump or pumps which are used ; 30 need not perform any metering action. The controls of , the apparatus are also simple and inexpensive, and the output of the apparatus as well as the ratios of various li~uids can be changed at will. Such changes of output and of the ratios can be effected in a simple and inexpensive manner hecause they need not be carried out while the respective liquids are in the process of flowing into the metering vessel. The ability of the improved apparatus to change the ratios of liquids which are admitted into the collecting vessel contributes to flexibility and versatility of such apparatus.
The utilization of a first metering device (such as the device 12 in the apparatus of FIG. 1 which has a fixed capacity exhibits the advantage that the a~paratus is even less likely to admit into the mixing tank a variahle quantity of the main or primary liquid component ~such as water) of the mixture in the collecting vessel. If the exact percentage of the main or major component of the mixture is of lesser importance, the apparatus can he equipped with a variable-capacity first metering device, such as the metering device including the containers 12 and 61 of FIG. 2. The provision of one or more overflow openings in the container or containers of the first metering device contributes to simplicity and accuracy of such metering device. A metering device with one or more overflow o~enings is considered to constitute a patentable innovation in its own right.
The regulating means 28, 58 which are used in the apparatus of FIGS. 1 and 2 exhibit the advantage ;, .8,.,rt~
that the containers of the metering devices 24, 26 and 27 need not be provided with reciproca~le mechanical regulating components and that such containers need not confine any mechanical seals. This simplifies the cleaning and rinsing of the containers of the metering devices 24, 26 and 27. The regulatin~ means including the cylinder and ~iston 82 of FIG. 3 exhibits the advantage that it is simple and inexpensive as well as that the effective volume of the container of the additional metering device 71 can be selected in advance with an~ desired d~gree of accuracy.
~ he feature which is shown in FIGS. 1 and 2, namely that the hori~ontal cross-sectional area of the container of at least one of the metering devices incxeases in a direction from its lower portion toward its upper portion is also believed to constitute an improvement which warrants independent patent - protection, the same as the feature of employing a composite collecting vessel including a mixing tank and a storage tank and the feature of employing a metering device including a plurality of containers which are connected in series as the containers 12 and 61 of the first metering device which is shown in FIG. 2. The meterin~ device including the containers 12 and 61 enhances the versatility of the ap~aratus by permitting the selection of different metered quantities of the respective li~uid. In addition, this metering device renders it possible to ensure even more satisfactory intermixing of the liquid constituents as well as to permit more rapid transfer of a metered .~
- ~8 -quantity of the respective liquid into the collecting vessel because the respective liquid can enter the mixing tank along three separate paths, namely through the conduit 59, through the valve 31 and through the valve 62.
Though it is possible to provide each of the additional metering devices with a discrete plenum chamber, the structure which is shown in FIG. 1 is preferred at this time because the container of the metering device 12 can be provided with a single outlet 16 which can discharge first liquid 2 into all three additional metering devices and enahles the first uid to rinse the containers for the additional liquids 21, 22 and 23 while flowing to~ard the mixing tank 32. Moreover, admission of first li~uid 2 into the containers of all three additional meterin~
devices 24, 26 and 27 renders it possible to begin with the actual mixing operation as soon as the valve 16a is openedj i.e., as soon as the first liauid is free to enter the plenum chamber 38 and to thereupon enter the liquid-containiny ~ortions of containers of the additional metering devices.
The provision of a bypass conduit 59 (FIG. 2) which can admit first li~uid into the collecting vessel directly from the plenum chamber 38 or from the outlet 16 of the container 12 also constitutes an independent inventive innovation. This feature ensures that the concentration of an additional liauid in the mixing tank 32 cannot exceed a predetermined maximum permissible value because the tank 32 can receive first !
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liauid simultaneously with one or more additional liquids.
The feature that the compressed gaseous fluid is circulated along a path which is defined in part by the collecting vessel 32, 33, in part bv the aftermixer 43 and in part by the source 1 of first liquid 2 (as described with reference to FIG. 1) enhances the economy of utilization of the gaseous fluid (such as carbon dioxide gas) which not only Lmpregnates the liquid but also contributes to expulsion of air.
The provision of impregnating means including the nozzle 5.6 in the conduit 9 which supplies first liquid to the respective metering device contributes to higher saturation of the respective liquid with gaseous fluid.
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