DE202021002948U1 - Pressing device for ground coffee - Google Patents

Abstract

Tamper 1 for pressing ground coffee 5 for portafilter 4 with a main spring 10, which reproducibly realizes the pressing force in the manual pressing process, characterized in that the base 3 of the tamper 1 receives an impulse, impact or impulse from a mass 9 via a plunger 6 , which compresses the grist 5.

Description

For the brewing / extraction process in portafilter machines (cf. US 4852474 ) For coffee, it is necessary to first press the ground coffee into a portafilter (to tamper).

If this work step is not carried out or if there is not enough pressure or compression, the result is a poor or uncontrolled extraction and an inferior drink. In extreme cases, the extraction can also fail completely if, for example, the water pressure escapes between the grist and the wall of the portafilter.

For pressing or tamping, punches are used that are manually pressed into the portafilter (e.g. US 375233 ). In this manual process, an attempt is made to achieve a constant coffee quality in the beverage by means of an exact amount of grist and always the same pressing as possible. This process is not only dependent on the type of coffee or the degree of grinding, but also other parameters such as humidity and water pressure and temperature are included.

A lot of effort is invested today in the design of the stamps or tamper for pressing the ground material.Examples for some manufacturers are: ECM Espresso Coffee Machines Manufacture GmbH, Pullman Espresso Accessories, JoeFrex GmbH, Motta S.p.A. and ESPRO Inc .. The tamper with flat and convex shapes or oversize, based on the portafilter diameter, are executed by them.

Ultimately, however, the quality remains largely dependent on the manual force or the pressure during pressing. In order to optimize, balance and compensate for this manual process step and thus the weak point, there are tampers today that are not only designed as simple stamps, but in which a spring tries to ensure that pressing is as constant as possible.

The problem here is that the operator's force is not limited, but only a stop for the detection of a certain force is now implemented. The force with which it is pressed against the spring stop and thus also on the grist in the portafilter remains undefined, since the manual force is neither limited nor reproducible despite reaching the end stop. An example of a tamper in this design, e.g. from ECM, is its pressure-regulating tamper.

In a further expansion stage, tampers are used that give signals to the operator when these stops or a certain force are reached (see the patent: US 7992486 B2 and the registration US 20040206243 A1 ), used. But here, too, the actual force of the operator remains unaffected and only a signal is generated to advise the user to reduce manual force.

From patents ( CH 53298 or DE 699 969 ) and center punching are known in mechanical engineering as hand tools (for example from Rennsteig Werkzeuge GmbH), which make it possible to achieve largely automated graining without a hammer. In these tools, a mechanism is clamped by pressing the center point on a workpiece, which accelerates a mass against the center point from a defined path. When this mass hits the punch tip, a blow occurs which allows the hardened punch tip to penetrate the workpiece. By adjusting the preload and thus the release force, the grain size can be varied, the manual force required can be reduced and grain size in workpieces made of different materials is possible.

Such a trigger mechanism is also widespread today in adjustable torque wrenches. In these hand tools, when the spring force is reached, there is only a release and thus a brief drop in the torque introduced on the screw. Triggering a hammer mechanism, similar to a pneumatic impulse wrench, is not common or known today in hand tools. The focus here is on the exact limitation of an adjustable torque.

According to this invention, the tamper described here optimizes the manual process of pressing ground coffee by always ensuring the same force. For this purpose, when a certain force or a certain path is reached, a defined impulse or impact is triggered on the grist and the direct manual force is interrupted. With this invention, an immediate interruption of the manual force is thus guaranteed and the manual process is automated to such an extent by the impulse that the grinding material is always consistently pressed.

In a further advantageous embodiment, the strength of the pulse or the energy of the blow is designed to be adjustable for the user.

By pressing by means of an impulse from the hammer mechanism, less manual force is required than the normally used 80 to 180 N (20 - 40 Ibs), so the effort for the operator can be significantly reduced.

If the base of the tamper is fixed in its rotation with respect to the housing and / or handle, this tamper can also be used for the so-called work step of leveling or smoothing (engl. To level) of ground material in the portafilter.

• - leicht gewechselt werden um etwa unterschiedliche Durchmesser des Siebdruckträgers zu realisieren,
• - einen Wechsel eines planen gegen einen konvexen Tamper ermöglichen oder
• - einen einfachen Austausch bei Beschädigungen erleichtern.

Thanks to the flexible interface to the Tamperbase, it can:

• - can easily be changed to realize different diameters of the screen printing carrier,
• - enable a change of a plan for a convex tamper or
• - facilitate easy replacement in the event of damage.

With tamping, as described, no decoupling of the acting pressing force and the applied actuating force has been achieved so far. With the tamper described here, it is possible to dimension the released mass accordingly and / or to implement a defined rigidity and / or damping instead of the hard stop for the pulse or impact, so that an actual decoupling takes place during manual actuation.

• 1 zeigt einen Tamper gemäß dieser Erfindung im Halbschnitt.
• 2 zeigt den initial manuell betätigten Tamper vor dem Impuls/Schlag.
• 3 zeigt den Moment des Auslösens der einstellbaren Kraftbegrenzung.
• 4 zeigt den Tamper mit maximal eingestellter Auslösekraft.
• 5 zeigt den Tamper mit minimal eingestellter Auslösekraft.
• 6 zeigt die Einzelteile des Tampers in einer Explosionsansicht.
• 7 zeigt den Tamper in der senkrechten Betätigungsposition mit Kaffeemahlgut und Siebträger.

An exemplary embodiment for the invention is shown in the drawings and is described in more detail below.

• 1 shows a tamper according to this invention in half section.
• 2 shows the initially manually operated tamper before the impulse / impact.
• 3 shows the moment when the adjustable force limit is triggered.
• 4th shows the tamper with the maximum set trigger force.
• 5 shows the tamper with the minimum set trigger force.
• 6th shows the individual parts of the tamper in an exploded view.
• 7th shows the tamper in the vertical actuation position with ground coffee and portafilter.

The barista's hand grabs the tamper 1 on the handle 2 and presses the base 3 of the tampers 1 to compress against that in the portafilter 4th contained grist 5 of the coffee 7th .

The portafilter 4th is advantageously placed on a working document for this purpose. During the initial pressing according to 2 becomes the handle 2 against the base 3 pressed. This is where the ram 6th initially against the secondary spring 7th in the housing 8th tense.

The secondary spring 7th is designed to hold the plunger 6th eccentric against the mass 9 through the housing 8th leads. As a result, the mass will be increased with further exertion of force 9 against the main spring 10 moved and thus pretensioned. This initial pressing process (see 2 ) is complete as soon as the plunger 6th through the housing 8th from the eccentric movement to the central axis 11th is centered towards.

On the ram 6th is a bevel for this 12th provided, which causes an increase in its outer diameter. The eccentric stroke movement is caused by the bore diameter in the housing 8th and the geometry of the bevel 12th on the ram 6th limited and from a defined stroke onwards can only be along the central axis 11th take place.

As soon as the plunger 6th into the hole of the mass 9 can slip, causes the now pretensioned main spring 10 an opposite movement of the mass 9 along the central axis 11th . In 3 this trigger moment is shown.

By the impact of the crowd 9 on the end of the ram 6th is in the base 3 causes a downward impulse in the direction of hand force, see 3 and 7th . With this impulse the grist becomes 5 pressed. The compression height is from the mass 9 and the preload of the main spring 10 depending on the moment of release.

By adjusting the preload of the main spring 10 , as in 4th and 5 shown, for example by a thread 13th , the spring force at the release moment (see 3 ) can be set. The eccentric stroke of the ram 6th is only determined by the geometrical position of the chamfer 12th certainly.

As soon as the direction of actuation changes and the tamper 1 from the portafilter 4th is taken out, make the main spring 10 and secondary spring 7th again the basic position of mass 9 and plunger 6th (please refer 1 ) here. In a portafilter 4th can thus the next coffee grind 5 be pressed.

The locking ring 13th prevents recording 14th for the base 3 am falling out of the case 8th and in that the secondary spring 7th completely relaxed or from the ram 6th solves.

List of reference symbols

1.

Tamper

2.

handle

3.

base

4th

Portafilter

5.

Regrind

6th

Plunger

7th

Secondary spring

8th.

casing

9.

Dimensions

10.

Main spring

11th

Central axis

12th

chamfer

13th

thread

14th

recording

15th

Circlip

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 4852474 [0001]
• US 375233 [0003]
• US 7992486 B2 [0007]
• US 20040206243 A1 [0007]
• CH 53298 [0008]
• DE 699969 [0008]

Claims (8)

Tamper 1 for pressing ground coffee 5 for portafilter 4 with a main spring 10, which reproducibly realizes the pressing force in the manual pressing process, characterized in that the base 3 of the tamper 1 receives an impulse, impact or impulse from a mass 9 via a plunger 6 , which compresses the grist 5. Tamper 1 after Claim 1 , characterized in that a change in diameter on the ram 6, for example by a bevel 12, limits an eccentric or eccentric stroke movement with respect to a housing 8 and forces the stroke movement into a coaxial movement. Tamper 1 according to one of the preceding claims, characterized in that the pretensioning of the main spring 10 on the mass 9 can be changed in that an upper limit of the housing 8 can be changed in its position along the central axis 11 via a thread 13. Tamper 1 according to one of the preceding claims, characterized in that the base 3 is fastened by a thread. Tamper 1 according to one of the preceding claims, characterized in that the handle 2 is mounted on the upper end of the housing 8 by means of a thread. Tamper 1 according to one of the preceding claims, characterized in that the impulse, impact or impulse is adapted by changing the weight, rigidity and / or damping of the mass 9 and / or the plunger 6. Tamper 1 according to one of the preceding claims, characterized in that the impulse, impact or force impulse is directed into the housing 8 and / or the handle 2 and is perceived as a signal by the user. Tamper 1 according to one of the preceding claims, characterized in that the base 3 cannot perform any rotational movement with respect to the housing 8 and / or the handle 2 due to geometric elements and thus enables the ground coffee 5 in the portafilter 4 to be smoothed.

Images