DE202013003598U1 - Electronic tamper (tamper) for ground coffee - Google Patents

Abstract

Device characterized in that the device is designed in the form of a handle (1) containing the annular printed circuit board (7a) with the measuring electronics and the display elements (5), (5a).

Description

State of the art

• a. Die Qualität der Kaffeebohnen
• b. Die Menge des Kaffepulvers pro Tasse
• c. Der Mahlgrad (die Feinheit, oder Grobheit der Mahlung)
• d. Die Wassertemperatur
• e. Der Druck, mit dem das Wasser durch das Kaffeemehl gepresst wird
• f. Die Menge des durchgepressten Wassers pro Portion
• g. Die Durchflusszeit dieser bestimmten Wassermenge durch das Kaffeepulver

(um nur die wichtigsten zu nennen)For the preparation of espresso, compliance with the following rules is indispensable:

• a. The quality of the coffee beans
• b. The amount of coffee powder per cup
• c. Grinding degree (fineness, or coarseness of grinding)
• d. The water temperature
• e. The pressure with which the water is pressed through the ground coffee
• f. The amount of water pressed per serving
• G. The flow time of this particular amount of water through the coffee powder

(just to mention the most important ones)

If one of these rules is disregarded, the coffee produced is spoiled and inedible.

To a. The quality of the coffee beans is guaranteed by the supplier and the critical buyer. That's a requirement.

To b. and c. Is the coffee grinder ( 5 ). For this purpose it has the following elements: A sealed container for the beans ( 28 ), an adjustable grinder ( 29 ), a reservoir for the ground coffee powder ( 30 ), a metering lever ( 32 ), a coffee ejection ( 31 ).

To the. and f. The factory setting of the espresso machine is responsible for this.

An actuation of the dosing lever ( 32 ) conveys a certain amount of coffee powder into the filter holder ( 21 ). This portafilter consists of a handle ( 20 ), an outer housing ( 21a ) with 2 bayonet warts ( 22 ), an inserted metal screen ( 23 ) and an outlet ( 24 ).

Train. The coffee powder is initially loose and forms in the portafilter a small hill ( 31a ). This hill is now manually, using a tamper ( 26 ) and firmly pressed together. A pressure of 10-20 kg should be applied to the tamper. To achieve this pressure, the filter holder must be placed on a stable surface ( 34 ) are supported. There are also hanging on the coffee machine attached tamper ( 27 ), where the pressure from below to be made by lifting the portafilter. However, these are not suitable for the desired pressure, since the correct pressing the coffee can be raised or overturned. In addition, a strong upward pressure often leads to injuries (overstretching of the wrist, tendonitis).

3 shows some tamper molds used. The easiest ( 25 ) consists of 2 plastic discs connected to a plastic rod ( 26 ) is a form with a pronounced grip, ( 27 ) is the described tamper for mounting on the coffee machine. All these forms have the crucial disadvantage that the density / strength of the ground coffee after tamping depends solely on the estimated manual force of the operator.

After tamping, a smooth, pressed slice of ground coffee is produced in the filter holder 7 , ( 33 ).

A glance at the function and components of an espresso machine shows why tamping is so important 8th (greatly simplified).

• – Wassertank (40)
• – Druckkessel (39) mit Überdruckventil (39a), Wasserstandsfühler mit Nachfüllventil (41),
• – Heizung mit Temperaturregelung (38)
• – Hochdruckpumpe 15 Bar (37)
• – Überdruckventil mit Bypass (36)
• – Siebträgereinspannvorrichtung mit Aufnahmebajonett (35) für den Siebträger

An espresso machine basically consists of the following functional groups:

• - Water tank ( 40 )
• - Pressure vessel ( 39 ) with pressure relief valve ( 39a ), Water level sensor with refill valve ( 41 )
• - Heating with temperature control ( 38 )
• - High pressure pump 15 bar ( 37 )
• - Pressure relief valve with bypass ( 36 )
• - Column carrier clamping device with receiving bayonet ( 35 ) for the portafilter

brewing process

The filter holder prepared with pressed ground coffee 7 ( 33 . 21 ) is inserted into the clamping device ( 35 ) with the help of the bayonet lock. The brewing process is started. The high pressure pump ( 37 ) starts and presses in the boiler ( 39 ) heated water in the filled filter holder. The amount of water and the temperature are regulated. The build-up pressure and the flow time through the ground coffee depend exclusively on the quality of the previous pressing (tamping) of the ground coffee in the filter holder! If this is too tight, the pressure exceeds the intended 15 bar. The pressure relief valve ( 36 ) opens and the water flows over the bypass back into the boiler. If the pressure is too soft, the water runs through the coffee powder almost unhindered. It does not build pressure, the aroma of the coffee are not dissolved out, the brewing process is completed after a few seconds. In both cases, the coffee is spoiled.

A skilled barista (professional coffee maker) usually succeeds in squeezing. But he has to practice constantly to be able to feel the right pressure. If several, even inexperienced people (changing staff or household use) operate the machine, good coffee is a matter of luck! A machine that costs several thousand euros produces ... garbage!

The technical solution of the problem:

1. Measurement technology

The strength (better: water permeability) of the ground coffee depends on many factors. Grinding degree, type of coffee, humidity and air pressure, level in the reservoir, pre-compression in the metering mechanism, etc., affect the result more or less. After many attempts, the following solution was found and tested:
The force with which the hand acts on the tamper is measured and displayed in 10 steps in a restricted area (12-21 kg). The resolution of one indicator level per kg has been determined empirically and has been proven.

The operation is very simple and intuitive. The collar ( 4 ) is twisted until its lens snaps over the middle LED. Now a Siebträgerfüllung is pressed. Press the handle ( 1 ) of the tamper with increasing force downwards, and thus the tamper disc ( 3 ) on the ground coffee in the filter holder. The LEDs now light up starting with LED 1 ( 5a = 12 kg) in succession. Is that through the lens ( 6a LED), this lights (due to the color of the lens), clearly recognizable, unlike the other LED's. Here you stop pressing and prepare the coffee. If the throughput time of the portion is about 25 +/- 3 seconds, the found setting is correct. From now on, any further coffee pressing will only be carried out until this LED comes on, which means that regardless of the operator, the coffee powder will always be compressed at the same pressure and a consistently good, correctly brewed espresso will be prepared. If the lead time is less than the prescribed 25 seconds, the collar ( 4 ) is shifted one or more steps in the direction of LED 10. If the cycle time is more than the prescribed 25 seconds, the ring is adjusted by one or more steps in the direction of LED 1. Once the correct setting has been found, the entire system, consisting of coffee grade, grinder, coffee machine and coffee pressure, is checked and optimally adjusted. The quality of the coffee will be consistent. Corrections due to weather changes require adjustment of the ring by a maximum of one step. In practice, this correction must be made at most once a month.

The clearly visible display of the tamper also facilitates the monitoring of coffee preparation by a supervisor.

2. Construction of the Tampers (Fig. 2)

• – Feder Nr. 1 (10)
• – Betätigungsmagnet des Reed-Kontaktes (9)
• – Ferritkern (13)
• – Feder Nr. 2 (16)
• – Begrenzungsnut (14)

The tamper disc ( 3 ) is at the end of a cylindrical, stepped axis ( 8th ) assembled. The disc is replaceable to allow easy adaptation to different portafilter diameter. The following assemblies are mounted or incorporated on the axis:

• - spring no. 1 ( 10 )
• Actuating magnet of the reed contact ( 9 )
• - ferrite core ( 13 )
• - spring no. 2 ( 16 )
• - limiting groove ( 14 )

• – Batteriefach für zwei Zellen (19, 19a)
• – Reed-Schaltkontakt (11)
• – Zylindrische Spule (12)
• – Haltebolzen (15)
• – Feder Nr. 2 (16)

In the upper part of the cylindrical, stepped drilled handle ( 1 ) is located:

• - Battery compartment for two cells ( 19 . 19a )
• - Reed switching contact ( 11 )
• - Cylindrical coil ( 12 )
• - retaining bolt ( 15 )
• - spring no. 2 ( 16 )

At the lower part of the handle is the housing body ( 7 ), in the interior of which an annular printed circuit board ( 7a ), on which the evaluation electronics and the LEDs ( 5 to 5a ) are housed.

The luminous ends of the LED's are clearly visible from outside through holes in the housing body.

Between the bottom of the case body ( 7 ) and the protruding axis ( 8th ) is a mechanical seal ( 17 ) assembled.

Between the housing body ( 7 ) and the handle ( 1 ) is in a groove of the collar ( 4 ) with the tongue ( 6 ) and the lens ( 6a ) stored.

Functional description of the tamper

Pressing down the handle ( 1 ) in the direction of the filter holder caused by the counteracting pressure of the coffee powder on the tamper disc ( 3 ), an immersion of the axis ( 8th ) in the handle body. In this case, the spring 1 ( 10 ) and the actuating magnet ( 9 ) to the reed switching contact ( 11 ). The reed switch contact closes and connects the batteries ( 19 . 19a ) with the evaluation electronics on the printed circuit board ( 7a ). An on-board oscillator circuit whose frequency-determining element is the coil ( 12 ) is activated.

Further depression of the handle causes the ferrite core ( 13 ) to the beginning of the inner bore of the coil ( 12 ) and the pressure flank ( 18 ) of the handle at the beginning of the still relaxed spring 2 ( 16 ). Each further depression of the handle by 1 mm increases the counterforce of the spring by 2 kg and guides the ferrite core ( 13 ) 1 mm further into the coil ( 12 ) one. The oscillator circuit is detuned and the degree of detuning is indicated by the LEDs.

The spring 2 ( 16 ) is linear calibrated, ie a compression of 1 mm increases the spring force by 2 kg, 10 mm travel thus corresponds to 20 kg of compressive force. However, since the minimum pressing force is 12 kg, the first 11 kg are faded out electronically, ie the LED no. 1 starts to light up when the pressing force has reached 12 kg. At 13 kg LED 2 lights up, etc. The pressure is increased until the LED lit by the lens ( 6a ) of the adjusting ring ( 4 ), which is emphasized by the color change caused by the lens. The collar is nothing more than a marker for achieving the correct (previously tested) pressing pressure.

The LEDs light up one after the other (dot display).

If the pressing force decreases, spring 2 initially relaxes ( 16 ). Spring 1 ( 10 ) pushes the handle in the upper rest position, wherein the actuating magnet ( 9 ) from the reed contact ( 11 ) and turns off the system. To protect the batteries, the system is always deactivated when not in use.

3. Table holder (Fig. 9)

The special, cylindrical design of the described Tampers and the semi-circular arrangement of the display LEDs allows the use of the Tampers as a stationary table device for catering use.

For this, the tamper is removed using a simple clamping device ( 51 ) on a table mount ( 9 ) and through the low-voltage cable ( 2a ) via the plug connection ( 2 B ) with the power supply built into the desk mount ( 54 ) connected. The table mount consists of a base plate ( 48 ) with adjustable feet ( 49 ), a pedestal ( 46 ), a height-adjustable support plate for the filter holder ( 50 ), the combination of a rail ( 44 ) and a rail traveler ( 43 ) and a toggle mechanism mounted on this combination ( 53 ).

The toggle mechanism ( 53 ) can be used together with the rail-runner combination ( 43 . 44 ) in height above the support plate for the portafilter ( 50 ), whereby the rail ( 44 ) in the selected height with the clamping screws ( 45 . 45a ) on the pedestal ( 46 ) is fixed. The sled ( 43 ) remains movable in the rail. Together with the height adjustability of the tamper ( 1 ) in the clamping device ( 51 ) and the height adjustment of the support plate ( 50 ), fixed with the clamping screw ( 47 ), the table holder can be adapted to any type of filter holder.

How the desk bracket works

The one with the coffee powder ( 31a ) filled filter holders ( 21 ) is placed on the tray ( 50 ) and the handle ( 20 ) with one hand. The hand lever ( 41 ) of the desk mount is pressed down with the other hand. This extends the angle ( 52 ) of the toggle mechanism ( 53 ) and the runner ( 43 ) moves together with the clamping device ( 51 ) and the tamper mounted therein ( 1 ) downward. The tamper disc ( 3 ) meets the loosely piled coffee ( 31a ) in the filter holder ( 21 ) and squeezes it together. Due to the leverage of the force required to depress the hand lever force is minimal. Nevertheless, the required pressing force is achieved and displayed with the LEDs in the tamper. The non-linear operation of the toggle mechanism is the execution of the pressing process very contrary. After completion of the pressing operation, a spring ( 42 ) the hand lever ( 41 ) and the sledge ( 43 ) back to the upper starting position. The table holder allows a very precise and pleasant work.

LIST OF REFERENCE NUMBERS

1

handle

2

battery cover

2c

Battery cover with power connection

3

Tamperscheibe

4

collar

4a

locking device

5

LED 1

5a

LED 10

6

Tongue / collar

6a

lens

7

housing body

7a

annular circuit board

8th

axis

9

actuating magnet

10

Spring 1

11

Reed switch contact

12

Kitchen sink

13

ferrite

14

limiting groove

15

retaining bolt

16

Spring 2

17

Mechanical seal

18

pressure flank

19

battery

19a

battery

20

handle

21

Espresso Machines

21a

Siebträgergehäuse

22

bayonet warts

23

scree

24

outlet

25

Tamper easy

26

Tamper with handle

27

Tamper for assembly

28

Container for beans

29

grinder

30

Reservoir for coffee

31

coffee ejection

31a

Kaffeehügel unpressed

32

apportioning

33

pressed coffee powder

34

document

35

chuck

36

Pressure relief valve

37

high pressure pump

38

heater

39

Pressure relief valve

40

water tank

41

refill

42

hand lever

42a

feather

43

carriage

44

rail

45

fixing screw

45a

fixing screw

46

 punching column

47

fixing screw

48

baseplate

49

feet

50

Support plate for portafilter

51

chuck

52

Toggle angle

53

toggle

54

power adapter

Claims (9)

Device characterized in that the device is in the form of a handle ( 1 ) is executed, which the annular circuit board ( 7a ) with the measuring electronics and the display elements ( 5 ) 5a ) contains. Device according to claim 1, characterized in that the measuring and indicating area is replaced by exchanging a single component ( 16 ) is almost arbitrarily limited or expandable. Device according to 1 and 2, characterized in that a selected measured value with a mechanical adjusting ring ( 6 ) or slider and a colored lens incorporated therein ( 6a ) can be marked. Device according to 1. and 2. and 3. characterized in that the measuring and display electronics ( 7a ) is automatically activated at the beginning of the pressing, is automatically deactivated when the pressing is finished. Device according to 1. characterized in that the handle ( 1 ) by its cylindrical shape for clamping ( 51 ) is prepared in a holding device, or a table frame ( 9 ). Device according to 1. characterized in that the bottom of the handle ( 1 ) mounted tamper disc ( 3 ) can be replaced by a screw against a tamper disc with a different diameter, or strength. Device according to claim 1, characterized in that the measured value determined by at least 10 or more LEDs ( 5 ) 5a ) is shown. Device according to 5. characterized in that the optional desk mount ( 9 ) with a toggle mechanism ( 52 ) 53 ) and a built-in power supply ( 54 ) for the measuring electronics. The electrical connection of this power supply with the tamper takes place by replacing the battery cover ( 2 ) through the battery cover with power connection ( 2a ). Device according to 1. and 3. and 8. Characterized, that the measured value can be displayed completely or partially by scaling the display, for. Eg measured value 0-10 kg = no indication, from 11 kg = start of the display.

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