US 20060254428 A1
A brewing apparatus for infusing compacted ground coffee in a grounds cup at a brewing station with heated water under pressure. At a brewing station, a piston head with an active seal that is spaced from the grounds cup wall during motion, extends into the grounds cup. When the piston head begins to compact the ground coffee it activates the seal to form a sealed upper end of a brewing chamber. Hot water is admitted to the brewing chamber to produce the coffee. When the brewing cycle is completed, the piston head displaces further to force additional coffee from the grounds. Then the piston head retracts to allow the infusion chamber assembly to be removed for cleaning.
1. Apparatus for brewing beverages including a housing and means for supplying a liquid to an infusible material under pressure thereby to produce a beverage, said apparatus comprising:
A) infusion chamber means supported by said housing including a side wall, an open top and a perforated bottom for receiving the infusible material,
B) piston means supported by said housing for being displaced into said infusion chamber means, said piston means including means for directing the liquid from the liquid supply means to the infusible material,
C) active sealing means mounted on said piston means intermediate said piston means and side wall means, said active sealing means including a seal, means for displacing said seal into an expanded state wherein said seal contacts said side wall when said piston means compacts the infusible material whereby said piston means and infusion chamber means form a brewing chamber in which the material is infused.
2. Apparatus as recited in
i) grounds cup means for receiving the infusible material and including said perforated bottom and a cylindrical side wall as said side wall, and
ii) grounds cup holder means for supporting said grounds cup means in the housing in alignment with said piston means.
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i) a piston rod
ii) drive means for moving said piston rod between retracted and extended positions, and
iii) piston head means attached to said piston rod including said active sealing means for compressing the infusible material in said infusion chamber.
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15. Apparatus for brewing coffee by infusing ground coffee with hot water under pressure comprising:
A) a housing,
B) means for defining a brewing station in said housing,
C) a infusion chamber assembly for being inserted into said housing at said brewing station, said infusion chamber assembly carrying the ground coffee and having dispensing port means for dispensing brewed coffee,
D) piston means mounted to said housing proximate said brewing station for compressing the ground coffee in said infusion chamber assembly in an extended state.
E) active sealing means formed with said piston means, said piston means including means for moving said active sealing means between a radially contracted state wherein said sealing means is spaced from said infusion chamber assembly and a radially expanded state wherein said sealing means forms a seal between said piston means and said infusion chamber assembly, and
D) means for supplying hot water under pressure to said infusion chamber assembly when the sealing means is in the radially expanded state and said piston means has compressed the ground coffee.
16. Apparatus as recited in
i) a water reservoir for containing water to be brewed,
ii) a pump for pressurizing the water for delivery to said infusion chamber assembly,
iii) a boiler for heating the water, and iv) means for interconnecting said water reservoir, pump and boiler in an operative relationship thereby to supply heated water to said infusion chamber assembly under pressure.
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22. Apparatus as recited in
i) a grounds cup holder with means for being supported in said housing at said brewing station including said dispensing port means, and
ii) a grounds cup having a cylindrical side wall and perforated bottom for passing brewed coffee to said grounds cup holder dispensing port, said active sealing means in its radially expanded state forming an upper limit of the brewing chamber.
23. Apparatus as recited in
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25. Apparatus as recited in
i) means for defining a fill station,
ii) means for supporting said infusion chamber assembly in said fill station,
ii) means for dispensing ground coffee into said infusion chamber assembly at said fill station whereby the infusion chamber assembly with the ground coffee can be transferred from said fill station to said brewing station.
26. Apparatus as recited in
a) a grinder for grinding coffee beans, and
b) a hopper for directing coffee beans into said grinder.
27. In a beverage brewing apparatus including an infusion chamber with a cylindrical side wall and a piston head movable within said infusion chamber to a brewing position, an active seal for generating a seal between said piston head and said side wall, said piston head comprising:
A) a first disk,
B) a second disk,
C) a peripheral seal having a central body portion and first and second means for attachment to said first and second disks, respectively, whereby said peripheral seal acts as a flexible coupling between said first and second disks, said peripheral seal having a third portion for engaging said cylindrical side wall when said first and second disks are compressed thereby to form a seal with the infusion chamber.
28. An active seal as recited in
29. An active seal as recited in
30. An active seal as recited in
31. Apparatus for brewing beverages including means for supplying a liquid to an infusible material under pressure thereby to produce a beverage, said apparatus comprising:
A) a housing with support means at a brewing station,
B) removable reusable infusion chamber means slidably supported by said housing including a side wall, an open top, and a perforated bottom for receiving the infusible material and engagement means for interacting with said support means whereby said infusion chamber means can be inserted and withdrawn from said brewing station, and
C) piston means supported by said housing for being displaced into said infusion chamber means, said piston means including:
i) means for directing the liquid from the liquid supply means to the infusible material, and
ii) sealing means intermediate said piston means and side wall means for contacting, said sealing means including a seal, wherein said seal contacts said side wall when said piston means enters said infusion chamber compacts the infusible material whereby said piston means and infusion chamber means thereby to form a brewing chamber in which the material is infused.
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This invention generally relates to apparatus for brewing beverages by directing a liquid, such as hot water, across a compacted infusible material, such as ground coffee beans, in a sealed infusion chamber.
A large number of commercial devices are available for brewing beverages, particularly coffee, by infusing material with a liquid. Prior art coffee makers have incorporated a variety of percolating, drip, steeping and other brewing approaches. A large number of these coffee makers were also designed to brew coffee in batches, for example, 4-cup to 12-cup batches. Such devices, however, were characterized by difficulties in maintaining coffee flavor over time, in controlling waste as occurred by making excessive coffee that was then discarded, and in cleaning and maintenance of the coffee makers.
The advent of espresso machines introduced new coffee brewing concepts. Espresso machines produce a small quantity of coffee at any given time, such as a cup of cappuccino or espresso. Espresso was brewed and continues to be brewed by placing an appropriate quantity of ground espresso coffee into an infusion chamber, compacting the ground coffee and closing that chamber. Hot water under pressure infuses the compacted coffee to extract its essence and directs the beverage to a cup.
This process has become very popular, and there are a variety of implementations primarily for use in espresso machines, but also for machines for brewing coffee. For example, U.S. Pat. No. 4,457,216 to Dremmel discloses an infusion chamber with hydraulically operated upper and lower pistons that close a scalding chamber. The scalding chamber contains coffee grounds and receives hot water. During the brewing process the loose coffee swells. When brewing is complete, the lower piston rises to compress the swollen grounds extract the brewed coffee that passes through the lower piston to a cup or other serving receptacle. After the brewing cycle is complete, the upper piston retracts. Then the lower piston can elevate to position the used compressed coffee grounds above the infusion chamber for removal.
U.S. Pat. Nos. 4,796,521 and 5,255,594 to Grossi disclose infusion chambers with a piston that delivers hot water by means of a metering unit. The piston is operated to allow the introduction of a filter carrier element and for compressing the coffee powder. U.S. Pat. No. 4,796,521 discloses a direct introduction of ground coffee from a coffee grinder into the infusion chamber. U.S. Pat. No. 5,255,594 discloses a motor drive.
U.S. Pat. No. 5,230,277 to Bianco discloses two pistons mounted on circulating ball screw actuators for closing the top and bottom of an infusion chamber. The pistons are brought together to compact ground coffee after which hot water is introduced for infusion. After the brewing cycle, both pistons can be raised so the lower piston can eject the used coffee grounds.
In U.S. Pat. No. 5,237,911 to Aebi a piston moves into an infusion chamber to compress ground coffee. The bottom of the piston comes into direct contact with the compressed ground coffee. There is no specific disclosure of a seal for preventing the escape of water from the infusion chamber past the piston.
U.S. Pat. No. 5,277,102 to Martinez discloses a vending machine with a lower piston. The lower piston rises to compact ground coffee against a fixed upper plunger or piston.
In U.S. Pat. No. 5,280,747 to Bonneville an espresso machine has a vertically movable snout for supplying hot water under pressure to ground coffee held in a filter. A cylinder or piston moves against the action of an antagonist spring to cause the snout to penetrate the package and compress the ground coffee.
U.S. Pat. No. 5,302,407 to Vetterli discloses a brewing or infusion chamber with a movable piston. The brewing chamber has an open top. A closure piston opens and closes the brewing chamber. Pressurized hot water causes the movable piston to move upward to compress the ground coffee.
In U.S. Pat. No. 5,402,706 to Locati an infusion chamber has a lower filter piston and an upper, two-part infuser piston. The infuser piston has a seal. One part of the upper piston slides into the other part against an opposing spring resistance. The seal remains in a contracted condition at a narrow diameter of a conical seat while the infusion piston enters the infusion chamber. During an operating stage, however, the distance between the two portions of the piston decreases causing the seal to shift upward to a maximum diameter of a conical seat. This process provides a seal and eliminates brushing and scraping of the packing to minimize wear and tear.
U.S. Pat. No. 5,911,810 to Kawabata discloses a coffee brewing system in which a vertically movable cylinder receives ground coffee and has a top opening. A vertically movable, upwardly urged plunger compacts grounds after second cylinder is elevated.
U.S. Pat. No. 6,035,762 to Ruckstuhl discloses an espresso machine with a brewing chamber in which two brewing chamber parts can be displaced relative to one another. In a closed position they form a brewing chamber for filter capsules. One of the members has multiple nozzles for directing hot water across the coffee. This approach allows the use of coffee pods of different sizes.
In U.S. Pat. No. 6,606,938 to Taylor, a beverage brewing apparatus includes a disposable cartridge that is initially pierced and vented by a tubular outlet probe when an arm pivots a water disposing head into a sealing relationship with the top of the removable cartridge.
U.S. Pat. No. 6,711,988 discloses an espresso machine with a variable volume infusion chamber. A piston with a static seal, shown as an O-ring, seals against and moves relative to an infusion cylinder. During brewing the piston elevates underwater pressure to allow swirling. When a predetermined pressure is obtained, a frothing valve opens. The piston moves toward the frothing valve to press the coffee grounds under a spring-generated force.
These and other features have been incorporated in a number of single-cup coffee makers, particularly for espresso machines for commercial use, as in restaurants, coffee shops and the like. However, such machines are expensive and not economically attractive to most consumers even though they may make the best coffee.
Recently several manufactures have introduced so-called “cup-at-a-time” coffee makers. They replace such pistons with hinged top units that latch to a base. A consumer must manually unlatch the hinged top unit, open it to expose a container for receiving either proprietary coffee pods or loose coffee. Then the consumer must manually close and latch the top unit to compact the coffee and form the sealed infusion chamber.
With cup-at-a-time coffee makers clean up requires the top to be reopened. If the coffee is made with loose grounds, the grounds cup must be removed so the used grounds can be discarded. If a pod is used, it can be lifted from a grounds cup without having to remove the grounds cup.
In many applications consumers desire automatic systems that incorporate coffee grinders. Such systems are characterized by locating the brewing chamber at an inaccessible location so it becomes impossible or, at best, very difficult, to clean the brewing chamber. Cleaning the brewing chamber in any such coffee maker is very important. If regular cleaning is not undertaken, oils and organic acids present in coffee attack the seal materials used to define the brewing chamber. Such substances also accumulate on the walls of the brewing chamber. If the seal slides over the walls, this material produces a rough surface that can damage the seals with use.
Some commercially available consumer-oriented coffee makers limit the consumer to proprietary prepackaged coffee filter pods. This can limit consumer choices. Also some consumer-oriented coffee makers are limited to making espresso. These factors and expense limit their market to consumers.
What is needed is apparatus for brewing a beverage, such as coffee, that is economical and easy to use. Specifically, what is needed is an economical coffee brewing apparatus that eliminates manual operation of latches, facilitates the incorporation of a grinder, simplifies cleaning and maintenance and is adapted for accepting ground coffee in a variety of forms.
Therefore it is an object of this invention to provide brewing apparatus for the consumers that has many of the advantages of more expensive commercial systems and that is economical, convenient to use and easy to maintain.
Another object of this invention is to provide brewing apparatus that eliminates manual latching mechanisms.
Still another object of this invention is to provide brewing apparatus that is adapted for use with a grinder while maintaining separation between their respective functions in order to facilitate use and maintenance.
Still another object of this invention is to provide a coffee brewing system that is adaptable for receiving coffee grounds in a variety of forms.
Yet still another object of this invention is to provide a coffee brewing system in which a grounds cup can be withdrawn for filling or cleaning without the need for releasing manual latches or breaking seals.
Yet another object of this invention is to provide a coffee brewing apparatus that can be used for brewing regular coffee or espresso.
In accordance with one aspect of this invention a beverage brewing apparatus includes a housing and a supply for liquid that infuses an infusible material thereby to produce a beverage. An open ending removable infusion chamber has a side wall, an open top and a perforated bottom for receiving the infusible material. A piston supported by the housing moves longitudinally with respect to the side wall. An active seal on the piston head expands into the side wall when said piston head reaches a compacting position whereby said piston and infusion chamber form a brewing chamber. Then the piston directs liquid to the infusible material under pressure.
In accordance with another aspect of this invention apparatus for brewing coffee by infusing ground coffee with hot water under pressure includes a housing that defines a brewing station. A infusion chamber assembly can be inserted into the housing at the brewing station. The infusion chamber assembly carries the ground coffee and has a dispensing port for dispensing brewed coffee. A piston mounted to the housing proximate the brewing station compresses the ground coffee in the infusion chamber assembly in an extended state. An active seal is formed with the piston. The piston moves the active seal between a radially contracted state wherein the seal is spaced from said infusion chamber assembly and a radially expanded state to form a seal between the piston and the infusion chamber assembly. Hot water is supplied under pressure to the infusion chamber assembly when the seal is in the radially expanded state and the piston means has compressed the ground coffee in said infusion chamber assembly.
In accordance with yet another aspect of this invention, a beverage brewing apparatus includes an infusion chamber with a cylindrical side wall and a piston head movable within the infusion chamber to a brewing position. An active seal generates a seal between the piston head and the side wall. The piston head comprises a first disk, a second disk and a peripheral seal. The peripheral seal has a central body portion and portions that attach to the first and second disks, respectively, whereby the peripheral seal acts as a flexible coupling between the first and second disks. A third portion on the peripheral seal engages the cylindrical side wall when the first and second disks are compressed thereby to form a seal with the infusion chamber.
In accordance with yet another aspect of this invention, apparatus for brewing beverages supplies liquid to an infusible material under pressure to produce a beverage. The apparatus includes a housing, a removable reusable infusion chamber and a piston. The housing carries a support at a brewing station for interacting with an engagement structure thereby to allow the infusion chamber to be inserted and withdrawn from the brewing station. The infusion chamber also has a side wall, an open top and a perforated bottom for receiving the infusible material. The piston is supported by the housing and can be displaced into the infusion chamber. The piston directs liquid from the liquid supply to the infusible material. The piston also includes a seal that is positioned intermediate the piston and the side wall for contacting the side wall when the piston enters the infusion chamber thereby to form a brewing chamber in which the material is infused.
The appended claims particularly point out and distinctly claim the subject matter of this invention. The various objects, advantages and novel features of this invention will be more fully apparent from a reading of the following detailed description in conjunction with the accompanying drawings in which like reference numerals refer to like parts, and in which:
In use a consumer brews one or two cups of coffee by activating a power-on switch 42 and by checking the water reservoir 30 for a sufficient water level. Then the individual grasps the handle 35 to withdraw the infusion chamber assembly 32 from the brewing station 33 in a straight-forward motion to deposit preground coffee or prepackaged ground coffee into the infusion chamber assembly 32.
If freshly ground coffee is desired, the individual inserts the infusion chamber assembly 32 into the fill station 40 through the fill station door 41 again with a straight-forward motion. If the fill station 40 has a coffee grinder, the individual moves the fineness adjustment knob 27 to a desired position and selects either a one-cup or two-cup quantity by means of a one-cup switch 43 or a two-cup switch 44. Activating the switch 45 initiates the grinding operation that deposits the appropriate quantity of ground coffee into the infusion chamber assembly 32. Alternatively the fill station would comprise a container for ground coffee and a dispenser for depositing pre-measured quantities of coffee into the infusion chamber assembly 32.
When the filling operation is completed, the individual merely withdraws the infusion chamber assembly 32 from the fill station 40, whereupon the fill chamber door 41 closes. Then the individual inserts the infusion chamber assembly back into the brewing station 33. These operations are achieved without any need to manipulate latches or other mechanisms.
When various visual annunciators, such as LEDs or like light sources 46, indicate brewing can begin and the brew/steam control selector 26 is in the brewing position, depressing a brewing switch 47 initiates the brewing operation. The consumer sees the result when brewed coffee begins to fill the coffee cups 37L and 37R. If only one cup is to be brewed, it is merely necessary to remove the cup 37R and center the cup 37L below the handle 35, or vice versa.
Emptying the used coffee grounds requires the individual to withdraw the infusion chamber assembly 32 from the brewing station 33 to dispose of the used coffee grounds and to clean the grounds cup. Periodically an individual can initiate a cleaning cycle whereby a compacting structure becomes readily accessible, as described later. The control 27 can include an access ring 50 that can be used to remove the front burr of the grinder for cleaning.
When it is desired to apply steam for foaming milk or for preheating a cup the consumer merely shifts the BREW/STEAM control 26 to a steam position. Steam will be dispensed from the bottom of the steam nozzle 38.
The water reservoir 30 has a hinged top 51 and rear wall 52 with a connector 53. The connector 53 includes a check valve (not shown) that closes when the water reservoir 30 is removed from the espresso machine 20 for filling. When a full water reservoir 30 is inserted and seated in the espresso machine 20, a connector on the apparatus, not shown but well known in the art, interacts with the connector 33 to open the check valve. Water is then available to a pump 54 shown in
The pump 54, when active, pumps cold water into a boiler 55 through a conventional flow meter 56. Tubing, not shown for purpose of clarity, conveys hot water from the boiler 55 to an inlet hose 57 on a compacting assembly 60 that forms a brewing chamber in cooperation with the infusion chamber assembly 32 that is inserted into the brewing station 33. Heat from the boiler 55 elevates the temperature of the cup warmer 23.
As shown in
The fill station 40 has a similar structure with a semi-cylindrical support portion 65 and two tangential planar wall portions 66. A shelf 67, similar to the shelf 63, supports the infusion chamber assembly 32 for receiving ground coffee. An interlock 68 provides an enabling signal to a controller when the infusion chamber assembly 32 is fully seated and aligned in the fill station 40.
Still referring to
Referring again to
A wavy spring 95 lies intermediate the top disk 83 and bottom disk 85. The top disk 83 and bottom disk 85 sandwich a seal 96 characterized by a radially contracted state and a radially expanded state. The top disk 83, bottom disk 85, perforated disk 91, guide ring 92, screw 93, wavy spring 95 and seal 96 thereby form a piston head 97 that attaches to the threaded rod 74 and provides an active peripheral seal structure. As described in more detail later, the seal 96 attaches to the bottom disk 85 and to the top disk 83. When the threaded rod 74 is in a retracted position, the wavy spring 96 exerts a force that tends to separate the top disk 83 from the bottom disk 85. Under these conditions the seal 96 relaxes, has a minimum diameter and is radially contracted. When the axial distance between the top disk 83 and bottom disk 85 decreases, the wavy spring 95 compresses and the diameter of the seal 96 increases so the seal 96 moves to the radially expanded state.
The seal 96 performs several functions. First, the seal 96 engages the cylindrical wall 112 of the grounds cup 102 to confine any water or brewed coffee to the brewing chamber 98. Second, the seal 96 assures that all the hot water admitted to the labyrinth in
In these views, however, the motor 71 and gear train 72 have retracted the threaded rod 74 and the piston head 97 to an upper limit or fully retracted position as defined when the radial arm 76 on the threaded rod 74 engages an upper limit microswitch 100. A lower limit microswitch 101 defines a lower-most position or range of travel. When the piston is fully retracted, the infusion chamber assembly 32 is easily removed from the brewing station 33.
Still referring to
Referring again to
In accordance with one aspect of this invention, the depth of the cylindrical wall 112 is at least equal to the depth of the grounds in the grounds cup 102 plus an amount that enables the piston head 97 to achieve a sealing relationship with the cylindrical wall 112 of the grounds cup 102. This depth provides flexibility to a consumer because a single grounds cup 102 will accommodate coffee in different packages or in different quantities. There is no need to inventory different grounds cups. Further, the grounds cup 102 easily separates from the grounds cup holder 34 for cleaning. This structure also allows an accessory element, such as a crema insert, to be located intermediate the grounds cup 102 and the grounds cup holder 34.
In the relaxed or radially contracted state shown in
As described later, when water temperature and other conditions are satisfied, the consumer pushes the brewing switch 47 in
As will be apparent, the position of the grounds cup 102 relative to the piston head 97 will not be held to close tolerances. Thus, it is possible for a misalignment to exist during normal operations. In contemplation of this possibility, the guide ring 92 shown in
Consequently the guide ring 92 protects the seal 96 from damage. Moreover there is no wear on the seal 96 during this downward motion.
The motor 71 continues to drive the threaded rod 74 and piston head 97 downward with the configuration shown in
As the ground coffee compacts, the load on the motor 71 increases. When the current reaches a first specified threshold, the motor 71 is de-energized. The gear ratios lock the piston head 97 in its vertical position. The seal formed by the skirt 126 now defines the top of the brewing chamber 98. This event enables hot water to pass from the boiler 55 through the hose 57 and the piston 97 and to permeate the coffee 130 under pressure.
As can be seen from
In one embodiment of this invention, the brewing cycle has another step. After the brewing cycle is completed the motor 71 is energized again to drive the threaded rod 74 downwardly thereby over compacting the coffee grounds 130 to extract additional beverage. This downward force increases motor current to a next higher threshold. When the threshold is reached, the motor 71 reverses to retract the threaded rod 74 and piston head 97 back to the position shown in 11A.
During the processes of compression and over compression and initial retraction, the seal 96, primarily the skirt 126, undergoes only minimal sliding against the cylindrical wall 112. As soon as the motor 71 produces any significant upward displacement during retraction, the wavy spring 95 begins to expand to separate the top and bottom disks 83 and 85 so the seal 96 with its skirt 126 retracts radially from the cylindrical wall 112. Consequently, the seal 96 will not wear and have a long life.
When the motor 71 fully retracts the threaded rod 74 and the piston head 97, the radial arm 76 again engages the upper limit microswitch 100 to de-energize the motor 71 and conclude the brewing cycle, so a consumer can remove a cup and drink the beverage. Also in this position, the consumer can easily remove the infusion chamber assembly 32 from the brewing station 33 for cleaning after each use and for filling with fresh ground coffee.
Generally this per use cleaning of the infusion chamber assembly 32 will be sufficient. Cleaning the piston head 97 can be done less frequently because during brewing the only elements in contact with brewed coffee and coffee grounds are the infusion chamber assembly 32 and the bottom surface of the piston head 97, that is, the perforated disk 90 and guide ring 92 and the surface of the seal 96 at a gap 135. The water under pressure prevents the bottom disk 85 including the labyrinth 87, upper disk 83 and internal surfaces of the seal 96 from accumulating any residue.
When it is desired to clean the piston head 97, the consumer initiates a cleaning cycle by activating a “clean” switch 136 in
The upper limit microswitch 100 and the lower limit microswitch 101 provide two other control inputs to the controller 140. Still other control inputs are provided by the interlock 64 that indicates the proper alignment of the infusion chamber assembly 32 in the brewing station 33. The interlock 68 indicates the proper positioning of the infusion chamber assembly 32 in the fill station 40. Other inputs include the power-on switch 42, the one-cup and two-cup switches 43 and 44, the brewing switch 47 and the grind switch 136.
Step 152 reads the input signal from the water level sensor 147 in
Once the water temperature is in an appropriate range, the consumer receives a notification as the illumination of a ready to brew light. This may initiate a time-out to limit the maximum interval before the brew button 47 in
Once the brew button 47 is actuated, control passes to step 162 to determine whether the infusion chamber assembly 32 is properly aligned by monitoring the interlock switch 64 shown in
Next the control unit 144 determines whether the one-cup switch 43 or the two-cup switch 44 has been actuated. As will be apparent, such switches should be ganged so only one of the two switches can be depressed at any time. Step 166 establishes the amount of water that must transfer through the brewing chamber 98 in response to the selection of one or two cups. Step 167 energizes the pump 154 so heated water flows to the brewing chamber 98 until the flow meter 56 records the specified quantity. When this occurs step 171 turns off the water.
Step 172 then energizes the motor to produce over-compacting. Step 173 monitors the current from the current sensor 142 until the Level 2 detector 146 indicates that second threshold has been reached. At that point step 174 reverses the motor and begins the retraction process. When the radial arm 76 engages the upper limit microswitch 100, step 175 transfers control to de-energize the motor at step 176. As will be apparent, when step 176 de-energizes the motor, the brewing cycle has been completed.
In summary, the espresso machine 20 of
The simplicity of this design allows the espresso machine 20 to be available for consumers with many of the advantages of the more expensive commercial systems. Yet this espresso machine 20 is easy to use because there is no need for a consumer to manipulate manual latching mechanisms. Moreover, owing to the fact that the seal 96 seals against the side wall 112 of the grounds cup 102 the machine can accommodate ground coffee or a variety of coffee pods of different diameters and in differing amounts and quantities up to some arbitrary maximum depending on the depth of the grounds cup 102. As a result, the espresso machine 20 in
This invention has been disclosed in the form of a particular espresso machine 20. It will be apparent, however, that variations could be incorporated or applied to the specifically enclosed embodiment without departing from the invention. For example, the compacting assembly 60 of