AU2010101102A4

AU2010101102A4 - An apparatus for use with a coffee tamp to detect pressure applied by the coffee tamp to the coffee grind

Info

Publication number: AU2010101102A4
Application number: AU2010101102A
Authority: AU
Inventors: Eliza Nootenboom
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-10-15
Filing date: 2010-10-08
Publication date: 2010-11-25
Anticipated expiration: 2018-10-08

Description

1 AN APPARATUS FOR USE WITH A COFFEE TAMP TO DETECT PRESSURE APPLIED BY THE COFFEE TAMP TO COFFEE GRIND Background of Invention 5 Technical Field The invention pertains to the field of beverage making and in particular to the field of making coffee drinks. 10 Background Art Coffee drinks are made by placing ground coffee beans, referred to as a coffee grind into a basket called a 15 filter basket. After the grind is compressed hot water is added to the grind as a result of placing a porta filter containing the filter basket and the coffee grind into a coffee machine. The water is then allowed to gradually percolate through the basket extracting oils from the 20 coffee grind. High compression of the coffee grind in the filter basket, typically a pressure substantially above 32 psi, will lead to water passing through the filter basket too slowly and impurities from the grind other than those desired will pass into a coffee drink. Low 25 compression of the coffee grind, substantially below 32 psi, will lead to water from a coffee machine passing through the filter basket too rapidly resulting in poor extraction of coffee oils from the coffee grind. 30 An optimal point of compression of the coffee ground is achieved when the coffee grind is compressed (tamped) into place with a device referred to as a coffee tamp, to a pressure of substantially 32 psi.

2 Additional factors can affect optimal extraction of oils from the coffee grind including temperature; grind size and amount of coffee placed into the filter basket and exposure to light. 5 The present invention deals specifically with the influence of pressure exerted on the coffee grind and more particularly with a device for use with a coffee tamp to achieve optimal compression of the coffee grind. 10 Prior art coffee tamps have typically fallen into two categories. A first type of coffee tamp has been entirely rigid in construction with no feedback provided to a user of the coffee tamp as to pressure exerted by the coffee 15 tamp upon the coffee grind. The rigid variety of coffee tamp can be used effectively by a highly experienced coffee maker who is able to accurately gauge the pressure applied to the coffee grind. However, development of sufficient dexterity in order to be able to precisely 20 sense the application of 32 psi applied to the coffee grind can take several years of experience. As previously, noted, for a person with limited experience, failing to properly tamp (compress) coffee grind into the filter basket can lead to inadequate extraction of oils 25 from the coffee grind in cases of under compression. Similarly, excessive compression of the coffee grind can lead to over extraction (extraction of impurities from the coffee grind), often referred to as "burning" of coffee, where the extract ceases to display a golden 30 colouration but instead is dark brown in appearance and bitter in taste in contrast to a sweet taste associated with properly extracted coffee essence. In both cases the result of over and under compression of the coffee grind 3 in the filter basket is a cup of coffee of poor quality and associated customer complaints. In order to resolve the above problems associated with 5 over and under compression of the coffee grind a spring has been included in a variety of tamps so as to enable an inexperienced person to appropriately compress the coffee grind. Sufficient compression of the spring provides an indication that the desired Level of pressure 10 of 32 psi has been applied to the coffee grind. The difficulty associated with a spring loaded coffee tamp is that a person highly experienced in the art of coffee making can often be reluctant to transfer from 15 using a fixed (rigid) tamp to a tamp that includes a spring. Further, highly experienced coffee makers can choose to apply small variations in pressure to a coffee tamp so as to achieve subtle variations in the texture and taste of coffee. These pressure variations are not 20 achievable with a traditional spring loaded tamp that has no capacity to lock into place for exclusively rigid use. Problems with background art: 25 rigid coffee tamp - limited ability to compress coffee to exacting pressure requirements, substantially 32 psi, unless a user of the rigid coffee tamp has had many years experience; 30 spring loaded coffee tamp - inability to operate in a rigid mode and accordingly not favoured by a person highly experienced in making coffee drinks; 4 both the spring loaded coffee tamp and the rigid coffee tamp suffer from an inability to provide dual modes of operation - inability to switch between a rigid mode and a spring loaded mode at high speed. 5 Summary of Invention 10 Technical Problem To substantially solve the problems as recited above. 15 Technical Solution A tamp having the capacity to lock into place so as to be operated in two modes, a first mode being a rigid mode of operation and a second mode being a mode in which a 20 spring located internally within the tamp can be used to regulate the degree of compression sought to be achieved using the tamp, typically substantially 32. psi. The present invention enables high-speed conversion between the two modes of use. 25 Advantageous Effects Advantageous effects include: 30 ability to provide dual modes of operation - rigid mode and spring loaded mode so as to provide a tamp that appeals to both experienced and inexperienced users.

5 In a first aspect of invention, an apparatus for use with a coffee tamp to detect pressure applied by the tamp to coffee grind including: 5 a longitudinal member; an elastic element; a locking mechanism; 10 a base plate, the longitudinal member, the elastic element; the locking mechanism and a handle are respectively connected in series; 15 so constructed and arranged that; compression of the elastic element is used to detect pressure sufficient to compress the coffee grind to a predetermined level in a filter basket; 20 the locking mechanism can lock the coffee tamp in a rigid position so as to prevent compression of the elastic element. 25 Another feature of the first aspect of invention includes where the longitudinal member is a shaft having a hole cut in an upper aspect of the shaft. Another feature of the first aspect of invention includes 30 where the elastic element is a spring. Another feature of the first aspect of invention includes where the locking mechanism further comprises 6 a sleeve having a step; a pin for insertion through the hole in the shaft; 5 compression of the handle towards the base plate compresses the spring; sufficient compression and rotation of the handle can move the pin over the step and lock the coffee tamp in a 10 rigid position. In a second aspect of invention, a method for constructing an apparatus for use with a coffee tamp including steps of: 15 a) installing a shaft in the apparatus; b) installing a spring in series with the shaft; 20 c) installing a locking mechanism in series with the spring; compressing the spring is used to detect pressure sufficient to compress coffee grind to a predetermined 25 level in a filter basket; activating the locking mechanism can lock the coffee tamp in a rigid position so as to prevent compression of the spring. 30 In a third aspect of invention, a method for using a coffee tamp having a shaft, a spring and a locking mechanism including steps of: 7 a) compressing the spring using pressure applied through the shaft; b) detecting compression of the spring sufficient to 5 compress coffee grind in a filter basket to a predetermined level; c) activating the locking mechanism so as to prevent compression of the spring. 10 Brief Description of Drawings FIG 1 discloses a best mode of invention in exploded 15 form. FIG 2 discloses the best mode of invention in assembled form. FIG 3 discloses a first generalization of present invention using a transparent casing. 20 FIG 4 shows a further generalization of present invention using electronic pressure detectors. FIG 5 shows a mode of use of present invention in industry. FIG 6 discloses the best mode of invention in assembled 25 form. Detailed Description 30 Best Mode FIG 1 discloses a best mode of invention in form of a tamp 10 having a capacity to lock into place and so operate in a rigid mode. As seen in FIG 1 a disk 12 is 8 seated at base of the tamp 10. Whilst the disk 12 is substantially flat the base of the disk 12 can, in use, be slightly elliptical so as to spread coffee evenly throughout a filter basket. 5 To right of the disk 12 is a shaft 14. The shaft 14 contains a hole at position 15 for insertion of pin 22. Above shaft 14 is a helical spring 16. The helical spring 16 is set to 32 psi at predetermined level compression of 10 the tamp 10. To right of the spring 16 is a sleeve 18. The sleeve 18 has screw threads cut into the sleeve 18 so as to enable a handle seen in FIG 2 and FIG 6 at 23, to be screwed into place on the sleeve 18. The sleeve 18 also contains a step 20 (a step 21 in FIG 6). The purpose 15 of the step 20 and step 21 is to permit locking of the pin 22 into place so as to lock the tamp 10 for use in a rigid mode of operation. FIG 2 and FIG 6 show the tamp 10 in assembled form, only 20 handle 23 remains detached from the tamp 10 so as to enable viewing of an internal aspect of the tamp 10. The tamp 10 is assembled by screwing the shaft 14 into the disk 12, The spring 16 is then placed over the shaft 14. The sleeve 18 is then placed over the spring 16. The pin 25 22 is then inserted through the hole at position 15. Once tamp 10 is assembled the pin is free to travel upwards so as to enable lower aspect of the sleeve 18 to close against an upper aspect of disk 12. The spring 16 is selected so that when the spacing marked at position 17 30 as seen in FIG 2 and FIG 6 is closed the tamp 10 will exert a pressure of 32 psi through the disk 12 against an underlying coffee grind, not shown but seen in FIG 5 in use.

9 Locking of the tamp 10, shown in FIG 2, can be achieved by driving handle 23 (when assembled) to left in direction of the disk 12 and then rotating the handle 23, clockwise with respect to the disk 12, when viewed from a 5 direction of the handle towards the disk 12. Rotation of the handle 23 will move the pin 22 up onto top of the step 20 thereby closing the spacing 17 as the lower aspect of the sleeve 18 moves against the upper aspect of the disk 12. 10 Locking of the tamp 10, shown in FIG 6, can be achieved by driving handle 23 (when assembled) to right in direction of the disk 12 and then rotating the handle 23, anti-clockwise with respect to the disk 12, when viewed 15 from a direction of the handle towards the disk 12. Rotation of the handle 23 will move the pin 22 up onto top of the step 21 thereby closing the spacing 17 as the lower aspect of the sleeve 18 moves against the upper aspect of the disk 12. 20 Locking the tamp enables the tamp 10 to be used in rigid mode. Unlocking the tamp 10 enables the tamp 10 to be used in a spring loaded mode by a user requiring assistance with appropriately compressing the coffee 25 grind (determining amount of pressure which needs to be exerted on the coffee grind). Mode for Invention 30 FIG 3 and FIG 4 show generalizations of concept of a dual tamp having features of rigid locking and inclusion of an indicator as to pressure applied by the tamp to underlaying coffee grind.

10 In FIG 3, a tamp 25, having a casing 24 is shown that is made of a substantially transparent material. Typically, for reasons of hygiene and in particular to avoid contamination of coffee grind with residue from the tamp 5 10, the tamp 10 shown in FIG 1 and FIG 2 is preferably constructed of stainless steel. However, in cheaper forms of construction, as seen in FIG 3 other materials, including plastic, can be used. 10 The casing 24 made from transparent material, seen in FIG 3 permits observation of movement of a longitudinal member 28 within the casing 24. The casing 24 is a guide for the longitudinal member 28. Substantial, compression of an elastic element 26, sufficiently sized and 15 constructed to be located within chamber of casing 24, provides a user of the tamp 25 with an indication that a pressure of substantially 32 psi. is being exerted against the coffee grind beneath base 27 of the tamp 25. The base 27 is used to transfer compressive pressure from the 20 longitudinal member 28 to the underlying coffee grind beneath the base 27. Further, structural generalizations can be associated with the tamp 25. Disk 12 as seen in FIG 1 is replaced by integral formation of a flat member into tamp 25 at base 27 so as to compress the coffee 25 grind. By way of generalization from FIG 3, it can be seen that other components of tamp 10 seen in FIG 1 can be integrally connected including integral connection of shaft 14 to disk 12 without loss of generality. The spring 16 shown in FIG 1 has been replaced by an elastic 30 element 26 of general construction in FIG 3. The elastic element 26 can take different modes including a helical spring, a leaf spring, a ball and a polyplastic. Any sufficiently sized and sufficiently resilient elastic element 26 so constructed and arranged as to serve as an 11 indicator of pressure applied to the coffee grind can be used. A locking mechanism is not shown in FIG 3. However, a 5 plurality of locking mechanisms can be contemplated without loss of generality. A transverse member can be used that runs transverse to longitudinal axis of the longitudinal member 28 so as to reversibly lock the tamp 25. Additional modes, not shown, can be contemplated so 10 as to reversibly lock the tamp 25 into place including a small flange fitted to the longitudinal member 28, the flange can be visually guided into a keyway running radially around the casing 24 so as to lock the tamp 25 into place for use as a rigid tamp. A further embodiment 15 of a locking mechanism that can be used in a general embodiment of the tamp 25 can include use of a screw thread, not shown, located internally within the casing 24 so as to screw the longitudinal member 28 into place, 20 A further locking mechanism particularly suited to embodiment shown in FIG 1, not shown, can include a spiral groove to replace the step 20 and step 21 of the sleeve 18 so as to permit smoother directional guidance between locked and unlocked modes of operation. 25 The plurality of modes of connection of elements of tamp 10 in FIG 1 and tamp 25 in FIG 3 including locking mechanisms, elastic elements, and integral connection between elements all fall within broad mode of present 30 invention being an ability to reversibly lock a tamp, where the tamp has the capacity when in an unlocked mode to provide a user with an indication of a requisite degree of compression of the coffee grind..

12 Whilst a standardized value of 32 psi has been quoted for optimal compression of coffee grind, clearly different pressure requirements can be met, by selecting different elastic elements so as to compress other substances used 5 for percolated extraction of beverages. FIG 4 shows a further generalization of principle of present invention. FIG 4 shows a base plate that is divided into two parts being lower base plate 30 and 10 upper base plate 32. Between the lower base plate 30 and the upper base plate 32 are chambers. The chambers house pressure detectors 34. The pressure detectors 34 detect degree of compression applied to coffee grind through the lower base plate 30 and the upper based plate 32 as a 15 compressive force is applied along body of tamp 35. Once compression reaches a desired level of pressure a signal is sent along signal line 33 to indicator 36. The indicator 36 can include a light that flashes green to denote fact that the desired level of pressure has been 20 reached. Alternatively, the indicator 36 can include a device to emit a beeping sound once the desired level of pressure has been reached. Mode of reversible locking and mode of indication of pressure of pressure are not critical in a generalized embodiment of present 25 invention. The indicator 36 can be turned off by switch 37. Electrical implementation is preferred in mode illustrated in FIG 4. A variety of forms of detectors 34 can be contemplated without loss of generality including piezoelectric crystals, magnetic detectors in which 30 movement of a metal element through a certain range is consistent with the desired level of pressure and will trigger transmission of an electrical signal through the signal line 33 to the indicator 36. In an alternative embodiment a partially mechanical implementation of the 13 embodiment shown at 35 in FIG 4 could be contemplated in which the detectors 34 take form of diaphragms and other mechanical elastic elements, not shown, that are subject to movement triggered by application of pressure 5 longitudinally through tamp 35. The detectors in mechanical form can then be coupled with the signal line 33 and indicator 36 being both in electronic form. Whilst the detectors 34 are shown at base plate end of 10 the tamp 35, the detectors 34 can be moved to different locations throughout the tamp 35. However, the detectors 34 have been located at distal end to handle 31 of the tamp 35 so as to avoid false readings being created by gripping of the handle 31 by a user. 15 Electrical implementation of tamp as shown in 35 of FIG 4 has advantageous effect that substantially no moving parts are involved (apart from small degrees of movement between the lower base plate 30 and the upper base plate 20 32 so as to compress and activate the detectors 34. Reduction of moving parts and access to cheap electronic circuitry to implement mode of construction shown in FIG 4 can reduce cost of tamp manufacture. 25 Industrial Applicability FIG 5 shows a mode of use of tamp 10 shown in FIG 1 in 30 industrial use. In use, coffee grind 40 is inserted into filter basket 38. The coffee grind 40 is compressed using tamp 42. After the grind 40 is compressed hot water is added to 35 the grind 40 as a result of placing a porta filter 14 containing the filter basket and the coffee grind into a coffee machine and allowed to percolate through the grind 40 and to pass out of the filter basket 38 through holes 44 and into a coffee cup. Downwards compression of the 5 tamp 42 will be such as to close the spacing 43 so as to indicate that a predetermined level of pressure is.being applied to the coffee grind. Without loss of generality the present invention can be 10 used to assist in percolation of hot water through a plurality of different forms of organic matter including chocolate.

Claims

1. An apparatus for use with a coffee tamp to detect pressure applied by the tamp to coffee grind comprising: 5 a) a longitudinal member; b) an elastic element; 10 c) a locking mechanism; a base plate, the longitudinal member, the elastic element; the locking mechanism and a handle are respectively connected in series; 15 so constructed and arranged that; compression of the elastic element is used to detect pressure sufficient to compress the coffee grind to a 20 predetermined level in a filter basket; the locking mechanism can lock the coffee tamp in a rigid position so as to prevent compression of the elastic element. 25

2. The apparatus as recited in claim 1 where the longitudinal member is a shaft having a hole cut in an upper aspect of the shaft. 30

3. The apparatus as recited in claim 2 where the elastic element is a spring.

4. The apparatus as recited in claim 3 where the locking mechanism further comprises 16 a sleeve having a step; a pin for insertion through the hole in the shaft; 5 compression of the handle towards the base plate compresses the spring; sufficient compression and rotation of the handle can 10 move the pin over the step and lock the coffee tamp in a rigid position.

5. The apparatus substantially as illustrated and described in the body of the specification. 15