WO2017118545A1

WO2017118545A1 - Tamper

Info

Publication number: WO2017118545A1
Application number: PCT/EP2016/080894
Authority: WO
Inventors: Otto Hauck
Original assignee: Otto Hauck
Priority date: 2016-01-07
Filing date: 2016-12-14
Publication date: 2017-07-13
Also published as: DE202016008590U1; WO2017118484A1

Abstract

The invention relates to a tamper for manually pressing coffee grounds or coffee powder, having a handle (1), a ram (3) with a pressing surface (5), and a shaft (9) which is mounted in a housing (7). The shaft (9) connects the ram (3) to the handle (1). The ram (3) can be moved by actuating the handle (1) in a pressing direction (z) which is orthogonal to the pressing surface (5). The handle (1) acts on the shaft (9) via a formfitting element (15, 17, 18) acting perpendicularly to the pressing direction (z).

Description

TAMPER

description

The invention relates to a tamper for manual pressing of ground coffee or coffee powder.

Professional coffee makers, called barista, must condense the ground coffee or coffee powder to make good-tasting coffee before brewing and thus squeeze into slices. Ground coffee or coffee powder is produced by grinding roasted coffee beans. Such a slice of pressed, ground coffee is also referred to as a puck. In the following text, the term "coffee also more representative of" coffee powder "and" ground coffee ".

As a tool, a barista uses a coffee strainer into which the ground coffee is ground (ground in) by means of a coffee grinder. For easier handling of the sieve this usually takes place in a portafilter receiving. A portafilter consists essentially of a receiving tray, which is preferably in the form of a cup-shaped cup, for the coffee grinder, laterally provided on the receiving tray lugs or tabs, and a handle. Below the receiving tray for the coffee sieve is an opening that communicates with one (single cover, single serving) or more spouts (usually two, double cover double serving).

To make the puck from the ground coffee, it is known to squeeze the ground coffee with a tamper called Kaffeestampfer. A tamper essentially consists of a handle and a punch with a surface for pressing the ground coffee. Exemplary tamper are known from the documents US 00D375233 S or DE 20 2008 009 380 Ul. After the pressing process, called tamping, the barista inserts the portafilter with the sieve containing the puck into a coffee machine to carry out the brewing process. In the course of the brewing process, hot water is forced through the puck, which absorbs the tasty ingredients of the ground coffee and as coffee penetrates through the opening and / or spouts into one or more of the coffee cup (s) provided by the barista.

In order to achieve a qualitatively excellent result, i. E. To achieve a tasty coffee, the barista must take care during the tamping that a sufficient pressing force is exerted on the ground coffee, since the puck should have a uniform thickness and density. For this purpose, a force corresponding to a weight of a mass of about 15 to 20 kg must be applied to the coffee grounds by means of the tamper. But for the good quality result, it is also extremely important that the surface of the puck is formed horizontally in all axes.

If the surface of the puck is formed obliquely, namely, this leads to an irregular thickness of the puck. In this case, the water is not uniformly pushed by the puck during the brewing process, but flows due to gravity along the inclined surface to a lowest point of the surface of the puck and accumulates there before being pushed by the puck. In this case, the portion of the ground coffee in this thinner portion of the puck is excessively leached while only relatively little water is forced through the thicker portion of the puck. Therefore, the ground coffee present in the thicker portion of the puck can not dispense its ingredients in the intended manner. The result is a thin, bad-tasting coffee.

The document US 2007/0132164 Al discloses a tamper having a handle and a punch which are connected via a shaft mounted in a housing. In an unactuated state, the punch protrudes from the housing. If this tamper is used according to the prior art in a coffee grinder and exerted pressure on the handle, the stamp is moved against a biasing force of a first spring in the direction of the housing. Upon reaching a given hubs according to a certain pressure force, a lock is released and the pressure force for pressing must be increased to overcome spring forces of other arranged in the handle and acting only after releasing the locking springs. With such a tamper is compared to other tampers from the prior art, although relatively easy to apply the required compressive force for producing the puck, but due to the applied high pressure force the problem that the portafilter despite hanging up on the tamper with only greatest difficulties can be kept horizontal. Since the tamper is also guided by hand, the barista must coordinate both hands during the application of the pressure force in such a way that the desired horizontal surface of the puck is created. This is already difficult for experienced baristas. For unskilled personnel, it is almost impossible to produce by hand (manually) a uniformly thick and compacted coffee puck.

It is the object of the invention to provide a tamper for manual pressing of ground coffee or coffee powder, with which the production of a uniformly dense and thick coffee puck is possible in a simple manner.

The invention is achieved by a tamper according to claim 1. Advantageous embodiments are set forth in the dependent claims.

An inventive tamper for manual pressing of ground coffee or coffee powder is provided with a handle, a punch with a pressing surface and a shaft mounted in a housing, which connects the punch with the handle. The punch is movable by operating the handle in a pressing direction orthogonal to the pressing surface.

The handle acts on the shaft via a positive locking element acting perpendicular to the pressing direction.

As a result, a guide of the stamp on the shaft is ensured within the housing, as long as the positive engagement is maintained. This means that the pressure on the handle is transferred to the shaft via the positive-locking element, whereby the shaft is moved in the pressing direction. Upon release of the positive connection, the movement of the shaft is interrupted in the pressing direction.

A stop element for limiting a stroke in the pressing direction can be provided on the handle.

The shaft may be formed at its end facing the handle in the form of a tube. In this case, one end of the handle can be accommodated within the tube.

The interlocking element may be guided through the end of the handle and be in engagement with a recess on an inner wall of the tube.

The positive-locking element may be formed from a prestressed ball, and the recess may have a shape of a circular segment.

Due to the configuration and arrangement of the positive-locking element, it is possible to release the positive connection when reaching a predetermined pressure force on the handle before the stroke is limited by means of the stop element. This pressure force, also known as the release force, corresponds to the optimal force for compacting the coffee puck. Thus, it is possible with the tamper according to the invention, by pressing (pressing) of the handle, the punch in a first phase of operation with relatively low pressure force away from the bottom of the housing. It is already being started to train the coffee puck. Thereafter, in a second phase upon reaching the release force, the optimum pressure force can be applied to complete the coffee puck. The user recognizes the achievement of the optimum pressure force by releasing the positive connection.

The biasing force for biasing the ball into the recess may be adjustable.

Since different views and opinions prevail regarding the optimal force for compacting the ground coffee under baristas, the triggering force can be adjusted by the adjustment according to the user's specifications. An outer dimension of the housing may be larger than an outer dimension of the punch. The stamp can rest against the housing in an unactuated state of the handle. In this case, a step is then formed by means of a peripheral surface of the punch and the supernatant (bottom) of the housing.

The tamper according to the invention can be brought into positive contact with a coffee sieve on account of the step. Therefore, an oblique placement of the punch can be easily avoided when the bottom of the housing rests on the entire edge of the coffee grinder. Therefore, it is ensured that the surface of the coffee puff formed by pressing is actually horizontal, i. parallel to the screen surface, and the coffee puck has a uniform thickness and density. The term horizontal is to be understood with reference to a correctly set up coffee machine (espresso machine), in which the coffee sieve is clamped with the coffee puck. Namely, it is not necessary to keep the coffee grinder and the tamper in a predetermined position during the tampering process as soon as the tamper has been placed on the sieve.

The applied state of the stamp on the housing can be brought about by means provided in the housing biasing element. Preferably, the biasing element may be in the form of a coil spring.

By the biasing element a return of the punch to the housing after use is ensured. In addition, it can be prevented that when placing the tamper on the coffee grinder is touched by a projecting from the housing punch the ground coffee and compacted.

Instead of the coil spring preferably used, other suitable springs, pneumatic or hydraulic components or magnets biasing elements in the spirit of the invention may be.

Further advantages and aspects of the invention will become apparent from the following description of a presently preferred embodiment with the appended drawings. In the figures shows: FIG. 1 shows a schematic view of a tamper according to the invention in the unloaded state,

FIG. 2 shows a schematic view of the tamper from FIG. 1 in the loaded state,

FIG. 3 shows a schematic sectional view of the tamper from FIG. 1 in the unloaded state,

Figure 4 is a schematic sectional view of the tamper of Figure 1 in the loaded state in a first loading phase, and

Figure 5 is a sectional view of the tamper of Figure 1 in the loaded state in a second loading phase.

A tamper according to a preferred embodiment of the invention will be described with reference to Figures 1 to 5.

The tamper has a handle 1 and a punch 3 with a pressing surface 5 in the form of a substantially planar surface. The pressing surface 5 gets in use of the tamper with the ground coffee in contact to compact this. As can be seen in particular from FIGS. 3 to 5, the handle 1 and the punch 3 are connected by means of a shaft 9, which is mounted in a housing 7.

The shank 9 is formed at an end directed towards the handle 1 in the form of a tube 9a. A cylindrically shaped end 1a of the handle 1 is inserted into the pipe 9a. On the inner wall of the tube 9a, two recesses 9b and 9c are formed. The recess 9b has the shape of a circle segment in cross-section, and the recess 9c has a substantially cylindrical shape. The recess 9c is closer to the open end of the tube 9a than the recess 9b.

Through the cylindrical end la of the handle 1, two holes are guided at right angles to the central axis of the cylindrical end la. By closer to one free end of the cylindrically shaped end la lying bore (in Figures 3 to 5, a lower bore) is guided a positive locking element having a biased by a spring 15 ball member 17. About a with the bore threaded engagement threaded pin (grub screw) 18, the biasing force of the spring is adjustable. A segment of the ball element 17 is received in a form-fitting manner in the recess 9b.

The second bore is located between the handle 1 and the bore described above. Through this second bore a the positive locking element similar stop element is guided. This has a cylindrical pin 19 instead of the ball element 17. The cylinder pin 19 is received in the recess 9c. Since a height of the recess 9c exceeds the diameter of the cylindrical pin 19, the cylindrical pin 19 is movable within the recess 9c between an upper edge and lower edge visible from FIGS. 3 to 5. A biasing force of a spring 13 of the stop element is also adjustable by means of a threaded pin with the bore threaded engagement (grub screw) 20. Instead of "grub screw", the colloquial term "grub screw" is used below. In Austria, such a screw element is also known as a "worm screw".

The biasing force of the spring 13 is set such that the cylinder pin 19 is retained in the recess without excessive frictional forces between the cylinder pin and the wall of the recess 9c arise. Excessive frictional forces would hinder or distort the application of the intended compressive force to produce the coffee puck.

The punch 3 is formed substantially in the form of a cylindrical disc. A side facing away from the handle 1 and the housing 7 of the punch forms the pressing surface 5, which gets in contact with the ground coffee during the pressing operation.

The pressing surface 5 is a substantially planar surface whose shape is not limited to a precisely planar surface, but which, for example, in shape a corrugated surface or a surface provided with small depressions and small protrusions may be formed.

At the handle 1 and the housing 7 facing side of the die 3 forming disc, a threaded connection 4 is provided in the form of an internal thread. This threaded connection serves to connect the punch 3 with an external thread formed on the end of the shaft 9.

The housing 7 is designed as a rotationally symmetrical part and has a cylindrical cavity in its interior. A bottom of the cylindrical cavity is provided with a bore through which the threaded connection 4 of the punch is guided. In addition, an annular spacer 6 is provided at the bottom, whose outer diameter corresponds to the inner diameter of the cylindrical cavity and whose inner diameter corresponds to the outer diameter of the threaded connection 4 and the shaft 9. Thus, the annular spacer 6 serves as a guide for the shaft 9 when the handle 1 is operated to move the punch 3 in the pressing direction z (along the direction of the rotation axis).

As already described, a handle 1 facing the end of the shaft 9 is expanded to a cylindrical tube 9 a. Around the shaft 9, a coil spring 11 is held as a biasing member between the bottom of the cylindrical tube 9 a and the annular spacer 6.

The coil spring 11 has a comparatively small spring constant, which is sufficient to push apart the tube 9a and the annular spacer 6 while pulling the punch 3 to the bottom 7b of the housing 7 until the punch 3 and the bottom of the housing 7 together in Appendix, as shown in Figure 1 or in Figure 3 is shown. In this case, a circumferential surface (cylinder jacket of the disk) 3a of the punch 3 forms a step with an annular bottom piece 7a of the housing 7. According to the embodiment, the bottom piece 7a is formed of a metal or a plastic material. Preferably, however, a PTFE material is used for the bottom piece 7a. Thus, it is possible to put the annular bottom piece 7a of the housing 7 on the edge of a coffee grinder. The disc of the punch 3 serves for exact centering. Since it is very easy to ensure that the annular bottom piece 7a of the housing 7 rests completely on the edge of the coffee grinder, it is ensured that upon actuation of the handle 1 and displacement of the punch 3 in the pressing direction z a coffee puck of uniform thickness and density is formed in the coffee grinder. Since the annular bottom piece 7a is preferably made of the PTFE material, it comes only to a low noise and low wear when placed on the edge of the usually metallic Kaffeesiebs.

The manufacture of coffee pucks takes place with the tamper according to the invention in two phases.

First, upon actuation of the handle 1, a pressing force is exerted in the direction of the axis of rotation of the tamper (the housing 7) in the pressing direction z. The pressure force is transmitted from the handle 1 via the ball 17 of the positive-locking element on the tube 9 a of the shaft 9. Since the spring constant of the coil spring 11 is merely sized to be sufficient to pull the punch to the bottom of the housing 7, it is already possible with a low compressive force to remove the punch 3 in the pressing direction z from the housing 7 until the coil spring 11 is completely compressed. This can be seen in FIGS. 2 and 4.

Thereafter, in a second phase, the pressure force on the handle 1 is increased until it is large enough to ensure that the prestressed ball element 17 is pressed out of the cross-sectionally circular segment-shaped recess. The stroke of the tamper is limited by a flange lb at the upper end of the cylindrical end la directly under the handle 1, which comes into contact with the upper edge of the tube 9a in the figures in Appendix. The compressive force in this second phase corresponds to a weight of a mass of 15 to 20 kg. The exact magnitude of the compressive force depends on the biasing force of the positive locking element, which is adjusted via the grub screw 18 according to the preferences of the barista using the tamper. Instead of using the flange 1b to limit the stroke of the tamper, the cylindrical pin 19 can alternatively be used, which can be brought into contact with the lower edge of the recess 9c in the figures for this purpose.

After relieving the handle 1 of the pressure force, it comes through the spring 15, which presses the ball member 17 below the recess 9c against the inner wall of the tube 9a, that the ball element slides back into the recess 9b, and by the coil spring 11 to a Return of the handle 1 and stamp 3 in the apparent from Figures 1 and 3 starting position.

Since the cylindrical pin 19 comes in the course of the provision against the upper edge of the recess 9c shown in Figures 3 to 5 in abutment, prevents the handle 1 and the shaft 9 with the tube 9a in the housing 7 in the course of the return operation accidentally be solved from each other. For the same reason, it is also not possible to intentionally or unintentionally detach the handle 1 from the housing 7 in the course of handling the tamper.

This makes it possible for untrained personnel in a simple manner, only with the tamper according to the invention and a conventional coffee grinder to produce a coffee puck, which has a uniform thickness and a uniform density, whereby a tasty coffee can be prepared. The use of specially designed tamper stations z. B. with special requirements for the coffee sieve or guides for the tamper is unnecessary.

Claims

claims

1. Tamper for manual pressing of ground coffee or coffee powder with a handle (1),

a punch (3) with a pressing surface (5), and

a shaft (9) mounted in a housing (7) and connecting the punch (3) to the handle (1), the punch (3) being actuated by operating the handle (1) in a direction orthogonal to the pressing surface (5) Pressing direction (z) is movable, characterized in that

the handle (1) acts on the shaft (9) via a form-locking element (15, 17, 18) acting perpendicular to the pressing direction (z).

2. Tamper according to claim 1, wherein

on the handle (1) a stop element (13, lb) for limiting a stroke in the pressing direction (z) is provided.

3. Tamper according to claim 1 or 2, wherein

the shaft (9) is formed at its end facing the handle (1) in the form of a tube (9a), one end (1a) of the handle being received within the tube (9a).

4. Tamper according to claim 3, wherein

the interlocking element (15, 17, 18) is guided through the end (1a) of the handle (1) and abuts with a recess (9b) on an inner wall of the tube (9a).

5. Tamper according to claim 4, wherein

the form-locking element is formed from a ball element (17) prestressed by means of a spring (15), and the recess (9b) has a cross-sectional shape of a circle segment.

6. Tamper according to claim 5, wherein

the biasing force for biasing the ball member (17) into the recess (9b) is adjustable.

7. Tamper according to claim 5 or 6, wherein

for moving the ball element (17) out of the recess (9b), a higher pressure force is required than for releasing the punch (3) from the housing (7).

8. Tamper according to one of claims 3 to 7, wherein the stop element (13) in the form of a through the end (la) of the handle (1) guided pin (19) is formed within a recess (9c) on an inner wall of the Pipe (9a) is movable.

9. Tamper according to one of claims 3 to 7, wherein the stop element in the form of a flange (lb) of the end (la) is formed, which is engageable with an upper edge of the tube (9 a) in abutment.

10. Tamper according to one of the preceding claims, wherein an outer diameter (dg) of the housing (7) is greater than an outer diameter (ds) of the punch (3), and the punch (3) in an unactuated state of the handle (1) the housing (7) is applied, wherein by means of a peripheral surface (3a) of the pressing surface (5) of the punch and a bottom (7a) of the housing (7) is formed a step.

11. Tamper according to claim 10, wherein the applied state of the punch (3) on the housing (7) is effected by means provided in the housing biasing member, which is preferably in the form of a coil spring (11).