Extraction assembly with rectilinear closure for the pressurized preparation of beverages from capsulesTechnical Field
The present invention relates to the preparation of beverages by the principle of extracting the substances contained in a filling (refill), known as a "capsule", by causing water to flow under pressure through the filling. The invention relates more particularly to an extraction assembly for a machine for preparing beverages, such as a coffee machine.
Background
In the prior art, beverages such as coffee, tea or hot chocolate are prepared from capsules containing a predetermined portion of the substance to be extracted. The advantage of this capsule form is the ease of handling of the prepared beverage, thus ensuring clean preparation without visible traces of substance, and controlling the reproducibility and quality of the prepared product.
The principle of extraction from the capsule generally involves (i) enclosing the capsule in a pressure-resistant chamber, (ii) piercing one face of the capsule, (iii) introducing some hot water into the capsule to create a closed pressurized environment to produce a liquid coffee or other extract, (iv) releasing the liquid extract through the opposite face of the capsule, and (v) collecting the extract in a container of suitable volume, such as a cup.
The problem of loading and removing capsules into and from an extraction system has been the goal of many patent publications.
Patent application EP 1090574a1 relates to an extraction device comprising a pair of jaws having a fixed jaw portion and a movable jaw portion hinged and mobile on the fixed portion, and a closing lever mechanism with which a plurality of arms interact to close (close) the movable portion on the fixed portion.
In the published document WO 01/30218a1, the principle is similar, but additionally a mechanism for ejecting the capsule is provided, which interacts with the pulling arm of the movable jaw to detach the capsule from the bottom of the extraction chamber when the jaw reopens.
From these principles, it is evident that a closure device is known having two parts, a fixed one and a mobile one, which optionally interacts with an ejector. However, these devices are manual closure devices in nature and are not well suited to having the closure function performed automatically. It should also be noted that, due to the movement of the articulated shaft, the system must be precisely designed and assembled in order to eliminate the clearances and problems that arise when assembling the parts together.
Patent application WO 95/17121 relates to a device comprising an assembly formed by a fixed piston and a movable cylinder, which is arranged facing a water heater. Between the water heater on the one hand and the fixed piston and cylinder on the other hand there is an area containing means for receiving, holding in place and discharging the package. The holding means and the receiving means are different devices. The former cannot be fully retracted and is arranged directly between the boiler and the cylinder to hold the sides of the package, while the latter is retractable and is arranged on one side of the cylinder to stop the package against the action of gravity only. Such devices are complex because they use various components to simultaneously hold and properly center the capsule (or package) in place in the extraction chamber. This involves some independent mechanisms for moving the devices to close the extraction system. The offset position of the retaining device can also lead to problems of interference or premature wear. Furthermore, the volume of such a device is relatively large due to the circumferential position of the retaining means and the water heater.
Patent application WO 98/47418 relates to a method for converting an espresso coffee machine with a vertical extraction operation of pre-dosed tablets used in a horizontal plane into an espresso coffee machine with a horizontal extraction operation of pre-dosed tablets that can be used in a vertical plane. The machine has a receiving and ejecting device comprising a single retractable part which can be moved under the extraction member using an electromechanical operating device separate from the device for actuating the extraction member.
Patent application WO 00/38558 relates to an extraction chamber for a robot, which is made up of two movable parts in a horizontal plane, one of which is supplied with hot water and the other of which has a filter, the two parts being mounted so as to pivot vertically relative to each other along their transverse axes.
Patent application WO 00/44868 relates to an extraction device comprising an extraction chamber formed by two parts which are horizontally movable so that they can move towards and away from each other, the parts being mounted on an eccentric shaft which can transmit pivoting movements to the parts in opposite directions, the device comprising a pivoting link between each eccentric shaft and each movable part which is braked so that the combination of the horizontal and pivoting movements links the steps of opening and closing the extraction chamber.
Disclosure of Invention
The aim of the present invention is to propose an extraction device that facilitates the insertion, correct positioning and ejection of the capsule while also overcoming the drawbacks of the devices of the prior art.
In this respect, the invention relates to an assembly for extraction under pressure for preparing a beverage from a capsule containing a substance to be extracted, the assembly comprising:
an extraction device comprising a first extraction sub-assembly and a second extraction sub-assembly movable to close on the first sub-assembly to form, in the closed position, an extraction chamber enclosing the capsule within a closing face, and to maintain sufficient space between the two sub-assemblies in the open position to allow insertion of the capsule between the two sub-assemblies,
means for retaining and positioning the capsule between the two subassemblies, the means partially closing the open space to retain the capsule between the two subassemblies; characterised in that the holding and positioning means are movable coaxially to the linear displacement of the movable extraction sub-assembly and are pushed linearly back into the retracted position by the second movable sub-assembly, so that the two sub-assemblies can be closed around the capsule.
Thus, unlike the known prior art devices, aligning (the devices) along the same displacement axis increases the reliability of the device by preventing interference and may also reduce the overall size of the device. The first sub-assembly may comprise a base on which the holding and positioning means may be mounted and slidingly guided for movement along the base.
Preferably, the holding and positioning means take the form of a single part able to centre the capsule within the open space along multiple axes in the closing face.
The retaining and positioning action of the axis in multiple directions is thus achieved with a single component, making the device simpler, more reliable and more compact.
The capsule can be held and correctly centred in a plurality of directions within the closed face by means of holding and positioning means, for example having an open cylindrical portion for holding and centring the capsule and an annular guide portion mounted around the base of the extraction sub-assembly.
In a preferred embodiment, capsule ejection means are provided for ejecting the capsule out of the assembly. The ejection means separate the capsule after each extraction, since the capsule is rather wet and is firmly pressed against the surface of the extraction means by the effect of the pressure. The ejection means help to eject the capsule even when the assembly is only slightly inclined with respect to the horizontal.
Preferably, during opening, as the second movable subassembly disengages from the first extraction subassembly, the ejection means for ejecting the capsule are operated with a rectilinear return action of the second movable subassembly. This structure may also help to simplify the system.
More specifically, the retaining and positioning means are locked in the retracted position when the extraction subassembly is closed and unlocked in the retaining position only after the ejection means have ejected the capsule. Unlocking of the retaining and positioning means in the retracted position can be directly achieved by means of the rectilinear resetting action of the sub-assembly when the movable extraction sub-assembly is disengaged. The holding and positioning means can then be returned to the holding position under the return action of elastic means, such as one or more return springs or any other equivalent means.
By linking the unlocking of the actuation of the holding and positioning means with the ejection of the capsule, a reliable continuous and controlled automatic function is achieved, ensuring that the capsule is ejected before there is sufficient space between the extraction subassemblies and the holding and positioning means return to the position for holding a new capsule.
The expelling means may be actuated in various ways. In a preferred example, the ejection device is elastically tensioned (strained) when the two extraction subassemblies are closed, and is released from its elastically tensioned state to cause ejection when the two subassemblies are reopened. An advantage of this arrangement is that it links the opening of the expelling and extracting sub-assemblies together without the need to use a separate mechanism for causing the expelling or for electrically or electronically controlled opening. For example, the ejection means may comprise a lever in the form of a ring, which is hinged on the fixed extraction subassembly. The rod may be tensioned by contact with at least one leaf spring or any other equivalent means supported by the holding and positioning means.
The movable extraction subassembly preferably has a linear actuation means, preferably of the piston type, which can be actuated by hydraulic or electric means for closing.
In a preferred embodiment, the first extraction subassembly is stationary. It comprises a capsule receiving area with a relief for opening the capsule. The second movable subassembly comprises a complementary capsule receiving area and means for supplying water to the capsule.
Drawings
Other features and advantages of the present invention may be better understood with reference to the drawings, which illustrate a preferred example of the invention.
Figure 1 is an overall perspective view of the assembly according to the invention in the capsule insertion position;
FIG. 2 is a cross-sectional view along I-I of FIG. 1 in the same position, wherein the capsule is held in place;
FIG. 3 is a cross-sectional view along II-II of FIG. 2 in an inclined capsule insertion position;
FIG. 4 is an exploded perspective view of an assembly according to the present invention;
FIG. 5 is a cross-sectional view taken along line I-I of FIG. 1, but in a position where the assembly is closed around the capsule;
FIG. 6 is a sectional view along II-II of FIG. 1, but in the capsule ejection position;
fig. 7 is a detailed view of the holding and positioning device of the assembly of the present invention.
Detailed Description
With reference to fig. 1 to 5, the extraction assembly 1 comprises extraction means for receiving the capsule 12 and extracting a liquid extract from the capsule by causing water to flow through the capsule under pressure. The extraction device has a first subassembly 10, preferably fixed, and a second subassembly 11, preferably mobile and in close cooperation with the subassembly 10. The subassemblies 10, 11 each have a receiving area 2 and 5, respectively, so that each area receives one face of the capsule when closed. The receiving area of the first subassembly 10 has a capsule opening member 22, which opening member 22 is typically a relief member (reliefelement), such as a plurality of tapered zones forming part of the pressure distribution plate 21.
The fixed subassembly 10 has a base or base 6 through which a flow channel 60 passes to allow the liquid extract to flow out of the extraction chamber. The base 6 is fastened to the body 8 at the sides as shown, for example, in fig. 4. The body 8 and the base 6 define an internal space 14 having an insertion side comprising a slot 15 and a discharge side comprising an outlet 16 for the capsule.
The body also includes a central bore 80 for the passage of the piston 20 which forms part of the movable extraction subassembly. The piston is mounted through a hole 80 of the body and is integrally connected with an extraction and spray device 5, the device 5 comprising a receiving area with piercing elements 50 for opening the capsule. The piston 20 and the spraying device 5 are coaxially assembled as a single part and provided with a water inlet passage 51 for dispensing water through the spraying device 5.
Through which the piston is resiliently mounted against a compression spring 150 disposed between a ring 140 fixed to the end of the piston and a cavity in the body. Sealing between the piston and the interior of the body is achieved using seals 30, 160 provided on each side of an annular barrier formed between the piston and the interior of the body. The two seals 30, 160 thus define a pressure chamber 81 between the piston and the interior of the body, which is expandable under the influence of hydraulic fluid entering the chamber provided through a fluid inlet 82 located at the top of the body (fig. 3).
It will therefore be understood that the mobile sub-assembly, mainly constituted by the piston 20 and the spraying device 5, is maintained in a position in which the extraction chamber is open, i.e. away from the receiving zone of the fixed sub-assembly, due to the compression (force) exerted by the spring 150 which acts between the ring 140 of the piston and the body 8. Thus, by passing hydraulic fluid into the pressure chamber 81, the spring can be compressed, thereby pushing the piston and the spray device as a single component in the closing direction F1.
In the open position of fig. 1 to 3, sufficient space 14 is maintained between the two opposite receiving areas 2, 5 so that the capsule 12 can be inserted through the slot 15. The capsule can be inserted through the slot 15 by the user himself, manually or with semi-automatic or automatic loading means, which are not described in the present application.
According to the invention, a retaining and positioning member 9 is provided between the movable subassembly 11 and the fixed subassembly 10 to hold the capsule in position within the closing plane P of the assembly. As can be seen in particular in fig. 7, the holding and positioning means 9 are arranged to immobilize the capsule on its axis in a plurality of directions by means of a portion 90 which is partly open and partly cylindrical. The component also has an annular guide portion 91 mounted around the base 6 of the fixed extraction subassembly. This guide portion 91, together with the preferably annular ejection means 7 (to be described in detail later in this description), acts as a retaining shoulder that retains the edge of the capsule. As shown in fig. 3, when inserted, the edge of the capsule is also retained by the upper peripheral edge of the base 6, on which a seal can be achieved when the spraying device is lowered. On each side of the member, the member extends along the body 8 with two fingers 93, 94 which engage in guide grooves 83, 84 of the body. These fingers are connected to the upper end of the recess by means of a resilient return spring 85 which, when the assembly is open, holds the holding and positioning means 9 in a holding position, i.e. a position in which the cylindrical portion 90 partially closes the space 14, in particular the outlet and the rim in a direction perpendicular to the direction of the outlet 16.
The cylindrical portion 90 of the member is positioned to partially surround the area 2 for receiving the capsule. Preferably, the portion 90 is close to the periphery of the receiving area and has a shape geometrically complementary to the edge 120 of the capsule, preferably extending over a circumference of 100 and 180 degrees, in order to hold the capsule along axes of multiple directions and to ensure that the capsule is centred. Preferably, this part encloses a portion of the space 14 so as to be centred on the side opposite to the slot 15. Thus, the part 9 is mounted coaxially around the base 6 along the axis I with respect to the linear displacement movement of the means for actuating the movable sub-assembly, i.e. the piston 20 and the spraying device 5.
The member 9 is movable along the cylindrical portion 61 of the base between a retaining position and a retracted position which allows the extraction sub-assembly to be closed around the capsule. In the position of figures 1 and 2, the part 9 is in a position to hold and position the capsule under the action of a return spring 85 which holds it on top of the cylindrical portion 61 of the base.
The extraction assembly also has a capsule ejection mechanism 7 which facilitates separation of the capsule after extraction and ejection thereof out of the assembly. The capsule expelling action should in fact work reliably within an unlimited number of extraction cycles, without having to manually remove capsules that have become wedged or stuck in the system. The ejection mechanism is provided to lift the capsule and disengage it from the surface of the receiving area 2. During extraction, the capsule is subjected to a great internal pressure due to the injection of water in the capsule enclosure. The capsule is opened by tearing the material in contact with the relief of the pressure distribution plate. Thus, after extraction, the surface of the capsule is "punched" by the reliefs of the pressure distribution plate, a force must be applied outwards from the receiving area surface to separate and expel the capsule.
The ejection mechanism is arranged to be elastically tensioned when the two extraction subassemblies are closed and to be released from the elastic tension to cause ejection when the two extraction subassemblies are reopened. To this end, the ejection mechanism 7 comprises a rod comprising a ring 71 and an end 72 hinged on the hinge pin 62 on the base 6 of the fixed extraction subassembly. The diameter of the ring of the rod is much greater than the receiving area 2 to allow the extraction assembly to close, but this diameter is smaller than the diameter of the rim of the capsule so that it can engage the rim and detach the capsule. Preferably, in the rest position, the rod 70 is housed in a recess 95 formed in the retaining and positioning element 9. For triggering the lever into the ejection position, the retaining and positioning element has an elastic element 92 in the form of a vane fixed on the periphery of the part 9, which cooperates with the end 72 of the lever. The free portion of the resilient member 92 extends above the recess 95 so as to be able to contact the end of the rod, and its function is to raise the ring portion upon discharge.
As shown in fig. 2 and 4, a mechanism is provided for locking the holding and positioning member 9 in the retracted position, so that the holding member 9 is retracted during ejection of the capsule using the ejection means. The locking mechanism has two engagement surfaces 96, 97 on the ends of the fingers 93, 94 of the component. When lowering the part 9 along the base of the fixed extraction subassembly, the surfaces 96, 97 cooperate to lock with the two projections 86, 87 housed in the guide grooves 83, 84 of the body.
Finally, a mechanism is also provided for unlocking the holding and positioning member 9 so that the member can be returned to its original holding and positioning position of fig. 1 and 2. This mechanism comprises projections 98, 99 in the fingers of the part 9, which are designed to be actuated by hooks 220, 221 located in the circumferential direction of the piston when the latter is raised.
The working principle of the extraction assembly will be explained below in order to facilitate the understanding of the steps of inserting, closing, opening and ejecting the capsule.
Fig. 3 shows the assembly with the pick-up subassembly in the open position. The assembly is preferably inclined with respect to the horizontal plane to facilitate the insertion and ejection of the capsule by gravity. The inclination may be between 5-90 degrees, preferably between 20-80 degrees. The piston is held in the retracted position by the compression spring 150 to create sufficient space 14. The holding and centering means 9 are engaged in a position for holding and positioning the capsule by means of a return spring 85. So that the capsule can be inserted through the slot 15. When the capsule is inserted, the edge 120 of the capsule abuts against the portion 90 of the part having a complementary shape, so as to centre the capsule in the middle of the extraction zone. The capsule can thus rest freely on the receiving area 2 against the pressure distribution plate 21.
Fig. 5 shows the steps of closing the assembly. The piston 20 is actuated by introducing hydraulic fluid into the pressure chamber 81. The piston actuates the spraying device 5 so that the device 5 closes against the capsule in the direction F1. As the piston is lowered, the holding and positioning member 9 is pushed back by the lower edge of the piston until the member is in the retracted position at the bottom of the base 6. At the end of the closure, this movable subassembly tensions the ejection mechanism 7. In particular, the seal 52 of the spraying device holds the rod 70 in the bent position, while the elastic element of the part 9 is elastically bent due to the relative movement of the part 9 with respect to the end 72 of the rod. When the member 9 is lowered, the fixed end (of the rod) forces the movable vane 92 to bend, thereby tensioning the discharge mechanism.
When the assembly is closed, the member 9 is then automatically locked in the retracted position by the locking mechanism. More specifically, the engagement surfaces 96, 97 of the fingers of the member 9 fit against the engagement surfaces 86, 87 of the body, thereby securing and locking the member 9.
The extraction operation of liquid extracts under hot water pressure is known per se and need not be described in the present application.
Fig. 6 shows the reopening and draining steps. Re-opening is achieved by raising the piston 20 and the spray device 5 in the direction F2. The part 9 is still locked by the above-mentioned locking mechanism while the piston is raised to gradually release the discharge mechanism 7 by releasing the tension created in the blade during closing. The lever of the ejection mechanism then pivots about the hinge pin 62, thereby disengaging the capsule and further tilting it relative to a vertical plane on the side of the outlet 16. The capsules then fall under gravity into a receptacle (not shown) for (placement of) empty capsules. The discharge mechanism acts as the piston rises. At the end of the piston stroke, the hooks 220, 221 of the piston then release the part 9, which hooks act on the projections 98, 99, moving the fingers 93, 94 apart and disengaging the engagement surface. The component 9 is then returned to the holding and positioning position by the return springs 84, 85.
The present invention relates to an extraction assembly mountable on a beverage dispensing machine or machine using any type of pre-dosed capsules. The dispenser or machine may contain one or more components depending on the required capacity. The assembly of the present invention provides a more reliable and faster load/extract/eject cycle than is commonly available.