WO2010013274A1

WO2010013274A1 - Espresso coffee machine infusion group

Info

Publication number: WO2010013274A1
Application number: PCT/IT2008/000531
Authority: WO
Inventors: Giampiero Rossi
Original assignee: ROSSI Corp Srl
Current assignee: ROSSI Corp Srl
Priority date: 2008-08-01
Filing date: 2008-08-01
Publication date: 2010-02-04
Anticipated expiration: 2011-02-01
Also published as: CN102118991A; CN102118991B

Abstract

The espresso coffee machine infusion group (1) comprises an infusion chamber (3) rotatably supported by a driving pin (5) slidable along a fixed guide in order to carry out a rototranslation with respect to a closure piston (4) between a closed position and an open position for the loading of a coffee powder load, the infusion chamber supporting, at its interior, an infusion piston (26) that can be moved between a retracted position and an extended position for expelling said coffee powder load, first means (7) being moreover provided for intercepting the rotation of the infusion chamber at its alignment angle with the closure piston, along with second means (8) for intercepting the translation of the infusion chamber for its rotation towards the load position.

Description

ESPRESSO COFFEE MACHINE INFUSION GROUP

DESCRIPTION

The present invention relates to an espresso coffee machine infusion group. Espresso coffee machines, as known, have an infusion group composed of an infusion chamber and a closure piston that are reciprocally movable between an open position of the infusion chamber at which the coffee powder load is loaded and a closed position of the infusion chamber at which the infusion is carried out. The traditional infusion groups can have rather complex movement kinematics and also result rather bulky, especially with regard to their height extension, so to be able to position the external dispenser of the infused drink above the glass in a convenient position for the user.

Such kinematic mechanism for moving the traditional infusion groups, moreover, can sometimes be not very precise or reliable, and give rise to a progressive wear of the parts, which during movement slide in contact with each other, and thus require a continuous maintenance.

The technical task proposed by the present invention is therefore that of making an espresso coffee machine infusion group that allows eliminating the technical drawbacks lamented by the prior art.

In the scope of this technical task, one object of the invention is that of making an espresso coffee machine infusion group that, while being extremely compact, especially with regard to its height extension, allows positioning the external dispenser of the infused drink in a convenient position for the user. Another object of the invention is that of making an espresso coffee machine infusion group which is structurally simple, precise and reliable. Not the least object of the invention is that of making an espresso coffee machine infusion group that does not have appreciable wear phenomena of its moving parts and consequently does not require frequent extraordinary maintenance operations. The technical task, as well as these and other objects, according to the present invention are achieved by making an espresso coffee machine infusion group according to claim L

Other characteristics of the present invention are also defined in the subsequent claims.

Further characteristics and advantages of the invention will be clearer from the description of a preferred but not exclusive embodiment of the espresso coffee machine infusion group according to the finding, illustrated as indicative and non- limiting in the enclosed drawings, wherein:

Figure 1 shows a side elevation view of an espresso coffee machine infusion group in which the infusion chamber is in open position;

Figure 2 is a side elevation view of the infusion group of figure 1 in which the support plate was removed for convenience and the infusion chamber is illustrated axially sectioned;

Figure 3 shows the infusion group of figure 2 in an intermediate step of the initial rotation of the infusion chamber in its closing travel;

Figure 4 shows the infusion group of figure 3 in the final step of the initial rotation of the initial rotation of the infusion chamber in its closing travel; Figure 5 shows the infusion group of figure 2 in an intermediate step of the final translation of the infusion chamber in its closing travel; Figure 6 shows the infusion group of figure 2 in the final step of the final translation of the infusion chamber in its closing travel;

Figure 7 shows a part of an espresso coffee machine infusion group in accordance with a preferred mode for achieving the invention, axially sectioned along the vertical median plane between the vertical support plates and in which the infusion chamber is in closed position;

Figure 8 shows the group of figure 6 in the discharge position of the spent capsule;

Figure 9 shows the infusion group of figure 6 in the position for loading a new capsule; and

Figures 10a - 1Od represent an additional system for locking the closure of the infusion chamber in the subsequent operating positions, in accordance with the present invention.

Equivalent details of the different embodiments are indicated with the same reference number.

With reference to the mentioned figures, an espresso coffee machine infusion group is shown, indicated with the reference number 1 in its entirety.

The espresso coffee machine can be of the semi-automatic type in which the coffee powder load, a single-use cartridge or pod containing the coffee powder quantity

(figures 7-9), is manually loaded, or of the completely automatic type in which the loose coffee powder load is loaded by means of a hopper 2 (figures 1-6).

The infusion group 1 comprises an infusion chamber 3, rotatably supported, preferably in eccentric position, by a driving pin 5 which is slidable along a fixed guide so to carry out a rototranslation with respect to a closure piston 4 between a closed position and an open position for the loading of the coffee powder load. The infusion chamber 3 is preferably made of plastic or another material with low friction coefficient.

The chamber 3 supports and guides an infusion piston 26 at its interior which is slidable between a retracted position and an extended position for expelling the spent coffee powder load.

A suitable stop element 39 is capable of stopping the infusion piston 26 during the travel of the chamber 3 towards the open position so as to bring it into the extended position.

The infusion piston 26 is provided with a filter 27 and has its stem 28 coaxially slidable with the infusion chamber 3 through a hole 29 made passing through the base

16 of the infusion chamber 3.

The infusion group 1 also has first means 7 for intercepting the rotation of ^cthe infusion chamber 3 at its first alignment angle with the closure piston 4, and second means 8 for intercepting the translation of the infusion chamber 3 for its rotation towards the load position (the first 7 and the second 8 interception means are illustrated only with reference to the embodiment of figures 1-6, but are valid for both the preferred embodiments of the invention).

Advantageously, centring means are also present adapted to maintain the infusion chamber 3 and the closure piston 4 coaxial during the terminal part of the closing path of the infusion chamber 3.

The infusion group 1 has two vertical, parallel and spaced support plates 9 between which the chamber 3 and the closure piston 4 are positioned.

The fixed guide is extended along the plates 9 and in particular comprises two slide slots 6 present in symmetric position on the plates 9. The driving pin 5 is transversely arranged through the slots 6.

The first intercepting means 7 comprise a first pair of pins 10 present in symmetric position on the plates 9, while the second interception means 8 comprise a second pair of pins 11, also present in symmetric position on the plates 9.

The chamber 3 has a flat external surface 12 of its lateral wall 13, intercepted by the first pair of pins 10 when the driving pin 5 slides along a first section 14 of the fixed guide close to the closure piston 4, and a flat external surface 15 of its base 16, intercepted by the second pair of pins 11 when the driving pin 5 slides along a second linear section 17 of the fixed guide.

More specifically, the chamber 3 is a hollow cylindrical block with open top 18, in which a faceting defines the flat surface 12 intercepted by the first pair of pins 10.

The second linear section 17 of the fixed guide in the first preferred embodiment of the invention has different slope with respect to the first linear section 14.

The driving pin is actuated by a movement mechanism shown only with reference to the embodiment of figures 1-6, but is valid for both preferred embodiments of the invention.

The movement mechanism comprises a connecting rod element 19 in turn hinged to a crank element 20 actuated by a motor 21 or, alternatively, manually.

The connecting rod element 19 is hinged to the end of the driving pin 5 outside the plates 9.

In particular, the connecting rod element 19 comprises two connecting rods hinged to the ends of the driving pin 5, and the crank element 20 also comprises two cranks present in symmetric position on the plates 9, to which they are pivoted, rotating in

22. The crank element 20 peripherally has a cam profile 23 adapted to activate switches

24 and 54 for stopping and starting the motor at the start and end travel of the infusion chamber 3 opening and closing.

The infusion chamber 1 has first elastic return means of the chamber 3 towards the open position, bound at one end thereof to the chamber 3 and at their other end to the plates 9.

Such first elastic means 25, shown only with reference to the embodiment of figures

1-6, but valid for both preferred embodiments of the invention, for example comprises a pair of first helical springs.

Second elastic return means 30 (shown only with reference to the embodiment of figures 1-6, but valid for both preferred embodiments of the invention) present between the external surface of the base 16 of the chamber 3 and a flange 31 of the stem 28, are adapted to bring the infusion piston 26 back towards the retracted position.

Such second elastic means 30 can comprise, for example, a second helical spring.

The base 16 of the infusion chamber 3 has an access path 32 for the infusion water, while the lateral surface inside the chamber 3 has, near the base 16 of the chamber 3, a seal ring 33 adapted to make a seal with the infusion piston 26 when the latter is in retracted position towards the base of the chamber 3, in order to prevent that during the infusion there are undesired leaks of the infusion water through the interstice between the perimeter edge of the infusion piston 26 and the lateral surface inside the chamber 3.

Reference will now be made to the embodiment of figures 1-6. The infusion group 1 has a scraper 34 adapted to remove the spent coffee powder from the chamber 3.

The scraper 34 is in particular a C-shaped profile having the two support stems 35 hinged, by means of pin 36, to the two plates 9 and a scraping element 37 which extends between the two support stems and remains simply supported due to its own weight on the external surface of the chamber 3.

The scraper 34 is in particular abutted on the external cylindrical surface portion of the chamber 3, diametrically opposed to the flat surface 12 which in turn is extended in a plane orthogonal to the support plates 9.

The chamber 3 has a smoothed external connection surface 38 between its external lateral surface and its apical surface, adapted to facilitate the passage of the scraper

34 from the apical surface to the external lateral surface of the chamber 3 or vice versa.

The stop element 39 is a parallelepiped pawl hinged in eccentric position, by means of pin 40, to the two plates 9: in particular, the pawl has an axis thereof parallel to the hinge pin 40.

Third means 41 for intercepting the pawl 39 are present, in particular comprising a third pair of pins 42 present in symmetric position on the plates 9, adapted to block the rotation of the pawl 39 at its angular position in which it operates the stopping of the infusion piston 26.

In addition, there are third elastic means 43 for bringing the pawl 39 back towards its angular position in which it operates the stopping of the piston 26.

Such third elastic return means 43 can be a pair of third helical springs constrained at one end thereof to the pawl 39 and at another end thereof to the plates 9. The third elastic return means 43 are only indirectly constrained to the plates 9, while they are directly anchored to the rotation plate 36 of the scraper 34. The related arrangement between the first pair of pins 10 and the third pair of pins 42 is such that, when the chamber 3 intercepts the first pair of pins 10 and the third pair of pins 42 intercepts the pawl 39, the latter has its greater axis aligned with the stem of the infusion piston 26 in turn aligned with the closure piston 4. Reference will now be made to the embodiment of figures 7-9, which is adapted for machines with capsule or pod load in which the infusion chamber, not having coffee powder dispersion problems, can have horizontal axis as shown in the closed position, and in the open position tilted or vertical open axis.

The stop element 39 is now composed of a stop pin 101 parallel to the driving pin 5 and slidable in a second pair of slots 102 present in symmetric position on the plates 9. In this case, the first pair of symmetric slots 6 has a horizontal extension while the second pair of slots 102 is vertical extended.

The end of the stem of the infusion piston 26 is preferably concave, in order to prolong the interaction with the stop pin 39 so as to ensure the complete extraction of the infusion piston 26 and consequently the correct expulsion of the capsule or pod 100. Since the driving and rotation pin 5 of the infusion chamber 3 is above the horizontal translation axis along which the infusion chamber 3 withdraws from the closure piston 4, a possible slight upward rotation of the infusion chamber 3 could lead the stem of the infusion piston 26 to prematurely pass over the stop pin 39. The concavity of the end of the infusion piston 26 stem in which the stop pin 39 is engaged slows the release from the latter, thus ensuring the correct execution of the pod or capsule 100 expulsion. Naturally, for that said in such machine type, neither the coffee powder load hopper nor the scraper are provided.

In such embodiment of the infusion group 1, a lip washer 103 is present, applied along the perimeter of the closure piston 4. The lip washer 103, also in case of high hydraulic pressures, allows reducing the closure force to the minimum, in particular the open force of the movement mechanism of the infusion chamber 3.

An overly high movement force would in fact tend to lift the machine.

In addition, during the final part of the infusion chamber 3 closure, there is a slight interference between the infusion chamber 3, the closure piston 4 which supports the lip washer 103 and the capsule or cap 100: this ensures that the user, when the driving of the crank element is manual, feels a slight resistance upon closure, perceived as secure and solid.

In order to create a slight resistance to the closure in the final part of the infusion chamber 3 closing, so that it can be perceived by the user as secure and solid, it is also possible to provide for one or more feet 104 fixed lateral to the closure piston 4 and adapted to be engaged with a certain friction in suitable external lateral seats (not shown) of the infusion chamber 3.

The vertical plates 9 in this case also have rubber guides 105 adapted to deaden the impact between the infusion chamber 3 and the vertical plates 9 at the conclusion of every rotation of the infusion chamber 3.

The rubber guides 105 render the movement of the infusion chamber 3 more silent, and thus on one hand contribute to providing the user with a correct functioning of the infusion group and on the other hand reduce the risk of undesired breaks of parts after impact. The vertical plates 9 also include, in the portion of their inner side close to the closure piston 4, the centring means adapted to ensure that the infusion chamber 3 and closure piston 4 are coaxial in the terminal closing part of the infusion chamber 3.

Such centring means comprise at least one curved guide 107 for the sliding of a curved external surface of shape matching the infusion chamber 3 and preferably a rectilinear guide 106 for the sliding of an external flat surface of the infusion chamber

3.

Providing centring means improves the insertion of the lip washer 103 in the infusion chamber 3, considerably increasing its duration.

With reference now to the figures 10a- 1Od, the additional locking system of the chamber 3 closure, particularly effective when the hydraulic pressures in play are considerable, comprises a lever 120 for controlling a lock pin 121.

The lock pin 121 can be rigidly (as shown) or operatively connected to the control lever 120.

The control lever 120 is hinged in 122 to the vertical plates 9 and in 123 to the connecting rod element 19 for moving the lock pin 121, so as to insert in through a first hole 124 present in the infusion chamber 3 and a second hole 125 present in the closure piston 4, which are aligned when the infusion chamber 3 reaches in the terminal position of its closure travel.

The functioning of the infusion group 1, for the sake of simplicity with reference only to the embodiment of figures 1-6, is briefly the following.

The initial configuration of the infusion group is the following: the driving pin is at the end of its opening travel; the first return means, by exerting a rotation force of the chamber 3 in clockwise sense, position the base of the chamber 3 against the first pair of pins, making the chamber 3 assume a vertical orientation suitable for the loading of the coffee powder quantity; the scraper 34 is set at the right edge of the top of the chamber 3, thus leaving the opening of the chamber 3 free so to not interfere with the coffee powder loading operation; the base of the stem of the infusion piston 26 is disengaged from the stop pawl 39 which in turn is positioned by the third return means, which exert a rotation force in clockwise sense on the pawl 39, against the third pair of pins; the second return means, which exert a force moving the base of the infusion piston 26 stem away from the base of the chamber 3, position the infusion piston 26 at the inner surface of the base of the chamber 3. After the loading of the coffee powder, the motor, through the crank element and connecting rod element, actuates the driving pin which starts the movement of the chamber 3 towards the closed position.

While the driving pin travels the second section of the fixed guide, the chamber 3 rotates until it is brought against the first pair of pins, in which it is aligned to the closure piston 4.

Subsequently, while the driving pin travels the first section of the fixed guide, the chamber 3 translates towards the closure piston 4 until it is engaged therewith. During the rotation and subsequent translation of the chamber 3, the base of the infusion piston 26 slides along a lateral face 44 of the pawl 39 and presses it, driving it in anticlockwise rotation against the action of the third return means. Before the end of the closing travel of the chamber 3, the base of the stem of the piston 26 is released from the lateral face 44 of the pawl 39 and allows the third return means to bring the pawl 39 back to the initial position in which it is wedged under the base of the piston 26. At the end of the closing travel of the chamber 3, the cam of the crank element activates the switch which controls the stopping of the motor and the start of the infusion.

During the closing travel of the chamber, the scraper 34 is moved from the right edge of the top of the chamber 3, moving towards the left edge of the top of the chamber 3 where there is the connection surface, then sliding on the connection surface in order to finally be positioned on the external lateral surface of the chamber 3.

During the infusion, the infusion water enters from the inlet path placed at the base of the chamber 3, while the infusion exists from an upper outlet path 45 present in the body of the closure piston 4.

The seal between the infusion chamber and the closure piston is ensured by a toroidal washer applied on the perimeter of the closure piston itself.

At the end of the infusion, the opening travel of chamber 3 begins.

When the driving pin slides in the first section of the fixed guide, the chamber 3 translates and opens.

During the translation guided by the first pair of pins, the infusion piston 26 is locked by the pawl 39 and is moved away from the base of the chamber 3, bring the spent coffee powder outside the chamber 3.

Subsequently, when the driving pin reaches the second section of the fixed guide and the base of the chamber 3 encounters the second pair of pins, the chamber 3 begins overturning.

During the overturning of the chamber 3, first the scraper 34 entirely clears away the top of the chamber 3, eliminating the spent coffee powder, and subsequently the pawl 39 is disengaged from the base of the infusion piston 26 stem, which is brought back to the base of the chamber 3.

At the end of the opening travel, the infusion group reassumes the initial configuration as described above.

In the case of a machine with pod or capsule load, with an infusion group in accordance with the second preferred embodiment of the invention, the lifting of the infusion piston during the opening of the infusion chamber (for the removal of the capsule or pod) is due to the stop pin which intercepts the base of the infusion piston stem which then, during the overturning of the infusion chamber, is released from the stop pin and returns towards the base of the infusion chamber, due to its own weight and/or the presence of the return spring.

It should be noted that the structure of the kinematic moving mechanisms of the infusion group together with the positioning of the outlet path of the infusion chamber above its inlet path allows maintaining the infusion group extremely compact.

In addition, the frictions tied to the movement of the infusion group are reduced to a minimum, both due to the intrinsic nature of the materials which come into contact, which have low friction coefficients, and because the contract surfaces are limited to the contact points between the interception pins and the external surface of the infusion chamber.

The espresso coffee machine infusion group as conceived is susceptible to numerous modifications and variations, all part of the scope of the inventive concept; moreover, all details can be substituted by technically equivalent elements. In practice, the materials used, as well as the size, can be of any type according to needs and to the state of the art.

Claims

1. Espresso coffee machine infusion group characterised in that it comprises an infusion chamber rotatably supported by a driving pin slidable along a fixed guide in order to carry out a rototranslation with respect to a closure piston between a closed position and an open position for the loading of a coffee powder load, said infusion chamber supporting, at its interior, a infusion piston that can be moved between a retracted position and an extended position for expelling said coffee powder load, first means being moreover provided for intercepting the rotation ^'of said chamber at its alignment angle with said closure piston, along with second means for intercepting the translation of said chamber for its rotation towards said load position.

2. Infusion group according to claim 1, characterised in that it comprises centring means adapted to maintain said infusion chamber and said closure piston coaxial during the terminal part of the closing travel of said infusion chamber.

3. Infusion group according to one or more preceding claims, characterised in that said fixed guide comprises a first pair of slots for the sliding of said driving pin, symmetrically positioned on two vertical, parallel and spaced support plates between which said chamber and closure piston are positioned.

4. Infusion group according to one or more preceding claims, characterised in that said first pair of slots has a prevailingly or completely horizontal extension.

5. Infusion group according to one or more preceding claims, characterised in that said first interception means comprise a first pair of pins present in symmetric position on said plates.

6. Infusion group according to one or more preceding claims, characterised in that said second interception means comprise a second pair of pins present in symmetric position on said plates.

7. Infusion group according to one or more preceding claims, characterised in that said driving pin is hinged to the ends of a connecting rod element in turn hinged to a crank element.

8. Infusion group according to one or more preceding claims, characterised in that said crank element is actuated by a motor and peripherally has a cam profile adapted to activate a switch for stopping and starting said motor at the start and end opening and closing travel of said infusion chamber.

9. Infusion group according to one or more preceding claims, characterised in that it has first elastic return means of said chamber towards said open position, constrained at one end thereof to said chamber and at the other end thereof to said plates. lO.Infusion group according to one or more preceding claims, characterised in that it has a pin for stopping the travel of said infusion piston during the travel of said chamber towards said open position, slidable in a second pair of slots symmetrically positioned on said plates.

11. Infusion group according to one or more preceding claims, characterised in that the end of the stem of said infusion piston is concave, in order to prolong the interaction with said stop pin.

12.1nfusion group according to one or more preceding claims, characterised in that said centring means comprise at least one curved guide for the sliding of a curved external surface of shape matching said infusion chamber, said at least one curved guide being provided at the inner surface of one of said vertical plates.

13. Infusion group according to one of the preceding claims, characterised in that said closure piston bears a lip washer along its perimeter.

14.1nfusion group according to one or more preceding claims, characterised in that it has one or more feet fixed on the side of said closure piston adapted to be engaged with friction in suitable external lateral seats of said infusion chamber.

15. Infusion group according to one or more preceding claims, characterised in that said vertical plates have rubber guides adapted to deaden the collision against said infusion chamber at the end of every rotation thereof.

16.1nfusion group according to one or more preceding claims, characterised in that it comprises a control lever of a pin locking the closure of said infusion chamber, hinged to said vertical plates and to said connecting rod in order to move said lock pin so as to insert it through a first hole present in said infusion chamber and a second hole present in said closure piston which are aligned when said infusion chamber reaches the end position of its closing travel.

17. Espresso coffee machine characterised in that it comprises an infusion group in accordance with one or more preceding claims.