HK1003777B

HK1003777B - Device for preparing hot drinks

Info

Publication number: HK1003777B
Application number: HK98102731.3A
Authority: HK
Inventors: Weber Rene
Original assignee: Eldom Rothrist Ag
Priority date: 1990-11-02
Filing date: 1998-04-01
Publication date: 1998-11-06

Description

Technical work

The present invention relates to a device for preparing hot drinks with a multi-way valve attached to a distribution block, whereby the distribution block is provided with a supply channel for hot water or hot steam to the multi-way valve and from there to various devices such as coffee filters, foam nozzles and/or residual water storage tanks, outgoing distribution channels and the multi-way valve with a perforated disc and a rotating control disc.

The multi-way valves used in these machines, usually 4/3-way valves, are used to supply, in a first switch position, the water heated in a water heater to the coffee grounds for espresso or, in another switch position, the hot steam from the foam nozzle for heating and foaming milk for the subsequent preparation of cappuccino. A third switch position, usually a medium one, is used to vent the device.

The need for high temperatures (well above 100°C) and pressures (above 15 bar) makes the multi-way valve subject to high stresses and severe wear and tear.

A device of the type described above is known from EP 0 307 497 A1 in which the multi-way valve is a ceramic valve with ceramic discs close together but moving against each other and fitted with distribution channels.

Description of the invention

The purpose of the invention is to improve a device of the type described at the outset in such a way that the multi-way valve can operate reliably for a long period of time without any extensive surface treatment of its parts or any lubrication.

This problem is solved according to the invention by a device having the characteristics of claim 1.

The dimensions of the invention are therefore inserted through the holes in the perforated disc to close the distribution channels, the position of which is determined by the rotation of the control disc with a guide frame.

Beneficial advantages of the invention are indicated in the dependent patent claims.

Brief description of the drawings

Further details of the invention are given in the following explanation of a device according to the invention, using the example of an espresso machine, with reference to the accompanying drawings. Fig. 1 shows a cut-out of a multi-way valve in the form of the invention, fitted to a distributor block of an espresso machine in a first position,Fig. 2 shows the same multi-way valve in a different position,Fig. 3 a view of the multi-way valve's orifice,Fig. 4 a view of the front side of the multi-way valve,Fig. 5 a longitudinal section through the same distribution block,Fig. 6 a view of the multi-way valve's control rod, andFig. 7 a section through the control rod along the circle between Achei and B in Fig. 6.

The figures show the same parts with the same reference.

Method of execution of the invention

The figures 1 and 2 show a distributor block of an espresso machine to which a multi-way valve 2 is attached. The multi-way valve 2 has four connections and three switching positions. It is used to supply hot water or hot steam generated in a heater to the coffee filter, the foam nozzle or the receptacle of the espresso machine. In the present case, since it does not depend on the training of the heater, the coffee filter, the foam nozzle, the receptacle or all the other parts of the espresso machine, the simplicity of the presentation was waived.

A first channel 3 is used to supply the hot water or hot steam from the heater to the multi-way valve 2 and from this channel 4, 5 and 6 go to the coffee filter, the foam nozzle and the receptacle. As shown in Figure 4, the distribution channels 4, 5 and 6 end at the multi-way valve 2 at a radius with the opening of the supply channel 3 as the centre.

The multi-way valve 2 has a valve housing 7 with a perforated disc 8 and a control disc 9. A control chamber 20 is separated from the valve housing 8 by a control chamber 1 into which the supply channel 3 enters and from which the control channels 4, 5 and 6 exit. The control chamber 8 is sealed against the valve housing outside the distribution chamber by a seal membrane 10 in its peripheral area. While the control chamber is fixed in the valve housing 7 in a rotating manner, the control chamber 9 can be rotated in it and thus in relation to the hole 8 can be rotated.

The perforated disc 8 is equipped with three continuous holes 11, 12 and 13, through which the plungers are moved axially through each of them. The plungers are used to close or seal the openings of the distribution channels 4, 5 or 6.

The studs 14 are fully recessed in the hole disc 8, but only to the extent that their head ends close approximately to the surface of the distributor block of the hole disc 8 by graduating their diameter and the diameter of the hole disc holes accordingly.

The 14th plunger is slightly longer than the 11th to 13th plunger, so when the head is fully immersed in the plunger, it protrudes a little way out of the plunger with the foot towards the control 9

The axial position of the bolt 14 in holes 11 to 13 of the hole disc 8 is determined by the rotation of the control panel 9. The side facing the hole disc 8 is thus provided with a guide frame for the bolt 14 on a ring surface between two radii R1 and R2. The formation of this guide frame can be seen from Figures 6 and 7. A deepening is provided in the sector marked by 15 of the ring surface bounded by the radii R1 and R2. The transition area between the levels of the ring surface designated in Figure 7 by N1 or N2 is provided with sloping flanks. The centre angle of the sector 15 is only 50°.

The condition of this formation of the control panel is that at least two of the 14 sockets are in each case in the control panel with their base on the undeepened part of the control panel. They are above the surface of the diaphragm 8 with their head end and keep the membrane 10 in a tight fit to the openings of their respective distribution channels, as is the case with the 14 socket of Figure 2.As can be seen from Figure 1, the plunger completely immersed in the screw is not attached to the guide frame, but the level N1 of the plunger is deliberately chosen so low that a gap 16 remains between the plunger and the bottom of the plunger. The control bar 9 therefore does not have to absorb the high pressure mentioned above applied to the plunger completely immersed in the screw 8.This measure contributes significantly to the lightness and durability of the multi-way valve.

In control-disc turns between each of the turns where one of the distribution channels 4, 5 or 6 is open, the control-disc formation described herein closes all three distribution channels.

The control panel 9 is further designed to be connected to a rotating knob (not shown) operated by hand, which preferably serves simultaneously as an on/off switch for the electrical elements of the espresso machine, e.g. pressure pump, etc. For this purpose, the control panel 9 has a protruding part fitted with a gear 17 through an opening in the valve housing 7. For ease of use, provision may also be made for a transition from smaller to larger knobs between the control panel and the control panel. To rotate the control panel, as required in the present example, between two switches of approximately 110°, it is sufficient, for example, to rotate only about 45° after the transition.

As can be seen from Figure 4, two of the distribution channels, channels 4 and 5, leading to the coffee filter and the foam nozzle, exit from the central supply channel 3 approximately to the right and left, while the third channel 6, leading to the receptacle, leaves below the central supply channel 3. This arrangement gives rise to a basic rule for the control panel 9, in which the recess in its conductive environment is in contact with the latter, leading to the receptacle, and is thus connected to the central supply channel 3, while the other two pressure pumped channels are electrically closed.

For coffee preparation or for the operation of the foam nozzle (hot water or steam), the control panel 9 is moved from its base position to the left or right, for example by turning the switch connected to it, opening either the distribution channel to the coffee filter or the foam nozzle, and the pressure pump is switched on at the same time.

After the coffee, hot water or foaming process has been completed, the control panel 9 is returned to its original position, the pressure pump is turned off again and the heater is vented.

Claims

Apparatus for preparing hot beverages, in particular espresso machine, having a multi-directional valve (2) flanged on a distributor block (1), the distributor block being provided with a supply channel (3) for hot water or superheated steam to the multi-directional valve and with distributor channels (4, 5, 6) extending therefrom to various devices such as coffee filter, foaming nozzle and/or collecting container, and the multi-directional valve being provided with a perforated disc (8) and a rotatable control disc (9), characterized in that provided between the distributor block and the perforated disc is a distributor chamber (20) in which the supply channel opens and from which the distributor channels extend and via which the distributor channels can be optionally connected to the supply channel, in that tappets (14) are plugged through the holes of the perforated disc in order to close the distributor channels, and in that the position of the tappets is defined by the rotational position of the control disc provided with a guide track for the tappets.
Apparatus according to Claim 1, characterized in that provided between distributor block and perforated disc is a diaphragm (10) which completely covers over the abovementioned distributor chamber and seals the perforated disc with respect to the distributor block, outside the distributor chamber.
Apparatus according to one of Claims 1 or 2, characterized in that the tappets can be countersunk in the perforated disc, owing to a graduation of the diameter thereof, and of the diameter of the perforated-disc holes, only to the extent where they terminate flush with the distributor-block-side surface of the perforated disc.
Apparatus according to Claim 3, characterized in that the guide track on the control disc is configured such that those tappets which do not have to close their appertaining distributor channel can be completely countersunk in the perforated disc, but, in this arrangement, do not come into contact with the guide track.
Apparatus according to one of Claims 1 to 4, characterized in that the perforated disc and the control disc are arranged in a valve housing (7) fastened on the distributor block.
Apparatus according to one of Claims 1 to 5, characterized in that a manually actuable rotary knob or rotary lever is coupled, via a gear mechanism, to the control disc in order to effect the transmission from smaller to larger angles of rotation.
Apparatus according to Claim 6, characterized in that a control-disc part projecting outwards through an opening of the valve housing is configured as a gear wheel (17) and is part of the gear mechanism.