EXTRACTION SLEEVE COFFEE MAKING APPARATUS

Abstract

Described is a system for roasting, grinding, brewing and dispensing coffee comprising a grinding and infusion assembly comprising a tubular extraction sleeve, infuser head and blade grinder, wherein the system further comprises a first seal, being a linear shaft seal for preventing a flow of coffee brew between the infuser head and inner surface of the extraction sleeve during extraction of the coffee grounds; a second seal, being a static seal for preventing a flow of coffee brew between the infuser head and grinder spindle when the grinder is not rotating and in the retracted position; and a third seal, being a rotary shaft seal for preventing the movement of coffee grounds between the infuser head and grinder spindle when the grinder is rotating in the extended position.

Claims

1. A system for roasting, grinding, brewing and dispensing coffee comprising: (a) a coffee cartridge containing: (i) unground and (ii) unroasted or part-roasted coffee beans, said cartridge having walls defining a cartridge chamber in which the beans are confined, wherein part or all of at least one wall of the cartridge is openable, and the openable wall of the cartridge is opposed to a slidable wall thereof, said slidable wall comprising: i. inner and outer surfaces, the inner surface being in contact with the beans; ii. a peripheral sealing portion on the inner surface; and iii. a central portion bounded by the peripheral sealing portion and comprising a screen for retaining the beans within the cartridge chamber while permitting a flow of coffee brew therethrough; wherein said cartridge is secured in a cartridge holder of: (b) coffee-making apparatus comprising: i. a source of hot water; ii. a collector head adapted to contact and support the outer surface of the slidable wall of the cartridge and to collect coffee brew flowing therethrough; iii. means for bringing the collector head into contact with the outer surface of the slidable wall and for sliding said slidable wall towards the openable wall of the cartridge, thereby opening the wall to produce an opened wall and exposed beans; iv. means for roasting the exposed beans; v. a grinding and infusion assembly for grinding the roasted beans to form coffee grounds and for delivering hot water from said source to said grounds, whereby coffee is extracted to yield a coffee brew; and vi. means for delivering said coffee brew to a drinking vessel for consumption; wherein said grinding and infusion assembly comprises: i. a tubular extraction sleeve having inner and outer surfaces and a sealing rim, the extraction sleeve being adapted to enter the cartridge chamber via the opened wall such that the sealing rim forms a face pressure seal with the peripheral sealing portion of the slidable wall of the cartridge, which seal isolates the exposed beans from the rest of the cartridge and contains them within an extraction chamber formed by the inner surface of the extraction sleeve and the central portion of the slidable wall; ii. an infuser head in fluid communication with the source of hot water and comprising infuser means comprising one or more outlets for the hot water, the infuser head being co-axial with the extraction sleeve and adapted to reciprocate between a retracted and an extended position within the extraction sleeve and to deliver hot water to coffee grounds within the extraction chamber, whereby coffee is extracted to yield a coffee brew; iii. a blade grinder comprising one or more blade(s) mounted on a spindle, which spindle is co-axial with the extraction sleeve and infuser head and connected to a motor, the grinder being adapted to rotate and reciprocate between a retracted and an extended position within the extraction sleeve, whereby rotation in said extended position levitates the beans off the inner surface of the slidable wall and fragments them to form coffee grounds within the extraction chamber; iv. a first seal, being a linear shaft seal for preventing a flow of coffee brew between the infuser head and inner surface of the extraction sleeve during extraction of the coffee grounds; v. a second seal, being a static seal for preventing a flow of coffee brew between the infuser head and grinder spindle when the grinder is not rotating and in the retracted position; and vi. a third seal, being a rotary shaft seal for preventing the movement of coffee grounds between the infuser head and grinder spindle when the grinder is rotating in the extended position.

2. The system of claim 1 wherein the first seal comprises a high pressure linear shaft seal rated to at least 10 bar, to at least 15 bar, at least 18 bar, at least 20 bar or over 18 bar pressure.

3. The system of claim 1 wherein the first seal comprises one or more radial O-rings.

4. The system of claim 1 wherein the second seal: (a) comprises a high pressure static seal rated to at least 10 bar, at least 15 bar, at least 18 bar, at least 20 bar or over 18 bar pressure; and/or (b) comprises an O-ring face seal; and/or (c) is open when the grinder is rotating and in the extended position.

5.-6. (canceled)

7. The system of claim 1 wherein the third seal: (a) comprises a low pressure rotary shaft seal rated to less than 10 bar; and/or (b) is mounted on the blade grinder spindle and/or the infuser head.

8. (canceled)

9. The system of claim 1 wherein the grinder is adapted to rotate bi-directionally within the extraction sleeve.

10. The system of claim 1 further comprising a tamping head adapted to tamp the coffee grounds, wherein said tamping head is comprised in said infuser head.

11.-12. (canceled)

13. The system of claim 1 wherein the beans are excluded from the peripheral sealing portion of the slidable wall of the cartridge by a fence disposed on the inner surface of the slidable wall.

14.-22. (canceled)

23. The system of claim 1 wherein the means for roasting the exposed beans comprises a source of a stream of air for levitating the exposed beans.

24.-28. (canceled)

29. The system of claim 1 wherein the hot water is pressurized and the extraction sleeve is adapted to serve as a pressure jacket to contain the pressurized hot water during delivery to the coffee grounds.

30. The system of claim 1 wherein the means for bringing the collector head into contact with the outer surface of the slidable wall and for sliding said slidable wall towards the openable wall of the cartridge is adapted to drive the slidable wall of the cartridge towards the openable wall thereof thereby exerting a force of the openable wall such that it opens, so exposing the beans and/or displacing the beans from the cartridge chamber.

31.-33. (canceled)

34. The system of claim 1 wherein the slidable wall of the cartridge further comprises a peripheral sealing portion on the outer surface thereof and wherein the collector head is adapted to form a pressure seal therewith.

35.-36. (canceled)

37. The system of claim 1 wherein the coffee beans are selected from: (a) whole and/or cracked coffee beans; (b) unroasted coffee beans; (c) part-roasted coffee beans; and (e) mixtures of the foregoing.

38.-43. (canceled)

44. A process for producing and dispensing brewed coffee comprising automated, sequential steps of roasting, grinding and extracting: (i) unground and (ii) unroasted or part-roasted coffee beans, the process comprising the steps of: (a) providing a coffee cartridge as defined in claim 1; (b) securing the cartridge in a cartridge holder of coffee-making apparatus as defined in claim 1; (c) roasting the beans; and then (d) grinding and extracting the roasted beans within a grinding and infusion assembly as defined in claim 1.

45.-47. (canceled)

48. The system of claim 37 wherein the unroasted coffee beans are selected from: (i) green coffee beans; (ii) dried coffee beans; (iii) pre-heated coffee beans; and (iv) mixtures of two or more of the foregoing.

Description

EXEMPLIFICATION

[0127] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which:

[0128] FIG. 1 shows plan and section views of a coffee cartridge for use in the system of the invention in closed configuration.

[0129] FIG. 2 shows top and bottom perspective views of the coffee cartridge shown in FIG. 1.

[0130] FIG. 3 illustrates schematically a process for roasting, grinding, brewing and dispensing coffee using the coffee cartridge shown in FIGS. 1 and 2 in a coffee making apparatus adapted for use therewith.

[0131] FIG. 4 shows schematically, in cross section, the engagement of the grinding and infusion assembly with the coffee cartridge. FIG. 4(A) shows the configuration of the first, second and third seals of the assembly when the grinder is in the retracted, non-grinding, position, while FIG. 4(B) shows the configuration of the first, second and third seals of the assembly when the grinder is in the extended, grinding, position.

[0132] It will be appreciated that part-roasted beans may be used in place of the unroasted (green) coffee beans referenced in the Example described below when practising the invention.

EXAMPLE 1

[0133] Referring now to FIGS. 1 and 2, the coffee cartridge (10) is substantially cylindrical with substantially cylindrical side walls (12), a bottom slidable wall (14) slidable against the side walls (12) and an openable top wall (16). The walls define a cartridge chamber (18) containing unground (whole) and unroasted (green) coffee beans (22). Part-roasted beans may also be used. The cartridge is formed of cardboard.

[0134] As shown in FIG. 1, an annular fence (30) seated on the inner surface of the slidable wall (14) prevents contact of the beans (22) with the peripheral sealing portion (24) of the inner surface of the slidable wall.

[0135] As shown in FIG. 2, the slidable wall (14) comprises a peripheral sealing portion (24) bounding a central portion comprising a coffee filter paper screen (shown stippled, 28).

[0136] The openable top wall (16) is formed by a number of sequentially overlapping hinged flaps (20).

[0137] Referring now to FIG. 3, the cartridge (100) is loaded into a cartridge tray (not shown) by the user, and the tray then moved into position beneath a roasting chamber (102) (FIG. 3(a)).

[0138] The collector head (104) in fluid communication with brew spout (113) is then pushed by a ram (not shown) and rises to engage and slide the bottom slidable wall (106) towards the roasting chamber, driving the beans (108) against the folded leaves forming the top wall (110), thereby hinging the sequentially overlapped flaps away from the chamber and so opening the top wall while exposing the beans (108) to the roasting chamber (102) (FIGS. 3(b) and (c)).

[0139] Directional jets of hot air at 200-300 C. are then re-circulated through the roasting chamber by a fan (not shown), fluidizing the beans and rapidly roasting them (FIG. 3(d)).

[0140] After roasting, a stainless steel extraction sleeve (114), within which is disposed, in piston and cylinder configuration, a blade grinder (118) disposed co-axially (and independently reciprocating with) an infuser/tamping head (116). The extraction sleeve forms a face pressure seal (140) with the peripheral sealing portion of the slidable wall of the cartridge. The blade grinder then then rotates and reciprocates within the extraction sleeve, so creating turbulence within the extraction sleeve which levitates the beans while the blades fragment them (FIG. 3(e)).

[0141] The tamping head (116) then pushes the slidable wall (106) together with the (now retracted and non-rotating) blade grinder blades and isolated coffee grounds back into the cartridge (100). The tamping head (116) comprises a peripheral lip (not shown) which scrapes coffee grounds from the walls of the extraction sleeve so that they fall towards the centre of the inner surface of the slidable wall. Thus, the tamping head (116) compresses the grounds against the slidable wall supported by the collector head (FIG. 3(f)) to form a compacted extraction bed of coffee grounds.

[0142] The collector head comprises a frustoconical portion (not shown) such that a second pressure seal is formed by compression of the peripheral portion of the outer surface of the slidable wall by the sealing rim of the extraction sleeve against the frustum of the collector head.

[0143] At this stage, the roasted beans are back within the cartridge chamber (180), but contained within a sealed extraction chamber formed by the inner surface of the extraction sleeve (114) and the central portion of the slidable wall, which comprises a coffee filter paper screen (shown as a broken portion of the slidable wall).

[0144] This process yields fresh roasted coffee grounds in the form of a compacted extraction bed of fine coffee particles confined within the chamber of the cartridge, but separated from the side walls (not shown in FIG. 3, (12) in FIG. 2) by the steel walls of the extraction sleeve (114).

[0145] Pressurized hot water is then fed through an infuser means (shown as a broken line) in the infuser/tamping head (116) from a high pressure pump via channels therein (not shown), forcing the hot water through the coffee grounds and extracting a coffee brew which is delivered to the user via the brew spout (113) (FIG. 3(g), where the arrows show the flow of hot water). Radial leakage of coffee brew is prevented by the second pressure seal between extraction sleeve and the collector head.

[0146] A reclosing plunger (not shown) then refolds the flaps into the closed position, so that the spent grounds and cartridge can be ejected into a waste compartment (not shown) without user intervention. It should be noted that the hinged flaps need not be refolded into a sequentially overlapping configuration at this stage of the process: all that is required is that the spent coffee grounds be substantially retained by the refolded flaps within the cartridge chamber prior to ejection into the waste compartment. In some embodiments, this step is performed manually by the user so that the spent cartridge and/or spent grounds can be disposed of or recycled immediately.

[0147] The features of the grinding and infusion assembly (150), and in particular the disposition of the various seals, are shown in more detail in FIGS. 4(A) and 4(B). For clarity, certain elements, including the four different seals, are labelled only in FIG. 4(B).

[0148] The grinding and infusion assembly (150) comprises a tubular stainless steel extraction sleeve (114) which forms a face pressure seal (139) with the peripheral sealing portion of the slidable wall (106) of the cartridge (120). The coffee beans (108) are thereby contained within an extraction chamber (180).

[0149] Located co-axially within the extraction sleeve (114) is the infuser head (122). The infuser head (122) is in fluid communication with a source of pressurized hot water (not shown) and comprises infuser means comprising one or more outlets for the hot water (shown as a dashed line). Disposed on the infuser head is a linear shaft seal in the form of a radial O-ring (130) for preventing a flow of coffee brew between the infuser head and inner surface of the extraction sleeve during extraction of the coffee grounds.

[0150] Located co-axially within the infuser head (122) is the blade grinder (118), comprising a rotatable and reciprocating spindle (136) on which are mounted two opposed cutting blades (138).

[0151] The blade grinder spindle (136) comprises two seals, a static seal (132) in the form of an O-ring face seal for preventing a flow of coffee brew between the infuser head and grinder spindle when the grinder is not rotating and in the retracted position (FIG. 4(A)), and a rotary shaft seal (134) mounted in the infuser head and operably coupled with the blade grinder spindle for preventing the movement of coffee grounds between the infuser head and grinder spindle when the grinder is rotating in the extended position (FIG. 4(B)).

[0152] As shown in FIG. 4(B), the static seal (132) is open when the grinder is rotating and in the extended position.

[0153] The infuser head (122) is adapted to reciprocate between a retracted and an extended position within the extraction sleeve independently of the blade grinder. During this operation, a seal is maintained by the linear shaft seal (130), which prevents a flow of coffee brew between the infuser head and inner surface of the extraction sleeve.

[0154] In the extended position within the extraction sleeve (not shown), and when the grinder is in its retracted position, the infuser head is in contact with the coffee grounds and so functions as a tamping head, compressing the grounds to form a compacted extraction bed.

[0155] The foregoing description details presently preferred embodiments of the present invention which are therefore to be considered in all respects as illustrative and not restrictive. Those skilled in the art will recognize, or be able to ascertain, using no more than routine experimentation, many equivalents, modifications and variations to the specific embodiments of the invention described specifically herein. Such equivalents, modifications and variations are intended to be (or are) encompassed in the scope of the following claims.