CH640648A5 - Dispensing and recording device for food and drink in the catering industry - Google Patents

Description

640 648

2nd

PATENT CLAIM Dispensing and registration device for food and beverages in the catering trade, with a lock into which several individual keys, each of which is assigned to a specific waiter, can be inserted, a portion output control unit which can be actuated by a fully inserted key, and several , the number of counters corresponding to the different keys, which, when the key is fully inserted, can be selectively activated by at least one soft iron coding element provided in this key, by actuating by the coding element a switch assigned to the respective counter, to which a permanent magnet spaced by the keyhole is located, characterized in that Hall generators (17) are provided as switches, and that adjusting magnets (16) are arranged on the side of the Hall generators (17) opposite the permanent magnets (11) in order to counteract the magnetic fields of the permanent magnets (11).

The invention relates to an output and registration device for food and beverages in the catering trade, with a lock into which several individual keys, one of which is assigned to a specific waiter, can be inserted, one of which can be actuated by a fully inserted key Portion output control unit and a plurality of counters corresponding to the number of different keys, which can be selectively activated when the key is fully inserted by at least one soft iron coding element provided in this by actuating a switch assigned to the respective counter by the coding element, which switch is activated by the keyhole spaced permanent magnet opposite.

A device of this type is already known (DE-PS 1524601). In the known device, the switches assigned to the individual counters are designed as protective gas switches, which close when the air gap formed by the keyhole is bridged by the assigned soft iron coding elements.

Such output and registration devices (also commonly referred to as waiter locks) have proven themselves in practice. In the development of modern coffee machines, for example, it has now been shown that the known waiter locks explained above stand in the way of trying to design the device as compactly as possible. The relatively large dimensions of the known lock cannot easily be reduced, since the magnets and protective gas switches must have a certain distance so that the magnetic fields do not influence one another and incorrect registrations occur. The device is also relatively expensive due to the inert gas switch used.

The invention has for its object to provide a device of the type mentioned, which is more compact and cheaper.

This object is achieved according to the invention in that Hall generators are provided as switches and in that adjusting magnets are arranged on the side of the Hall generators opposite the permanent magnets in order to counteract the magnetic fields of the permanent magnets.

Hall generators have the advantage that they emit a Hall voltage even with a relatively weak magnetic field. Accordingly, the construction of the lock can have small dimensions since the magnets do not have to be large. The thought of just that

To replace the protective gas switch of the known device by Hall generators, the problem was opposed that even if the key was not inserted, there would be a non-negligible field strength of the permanent magnets in the area of the Hall generators, which under certain circumstances would lead to incorrectly generated counting pulses; A measurable Hall voltage is already generated even by small field strengths.

Although it is already known from CH-PS 549845 to arrange small permanent magnets in the vicinity of the reed contacts in a control device with a reading closure, which has reed contacts at certain points, for pre-polarizing the reed contacts, however, this measure could not provide any suggestion for Give solution to the problems with the use of Hall generators; because in the known control device at least one permanent magnet is provided in the key as the coding element, the presence of which at a certain point in the lock actuates the associated reed contact, depending on the polarization of the permanent magnet provided in the lock at the relevant point. In the device according to the invention, however, a soft iron coding element is provided, while in the lock both a permanent magnet and an adjusting magnet are provided at a certain point. The adjusting magnet is intended to counteract the field of the permanent magnet. In the known device, however, only a single permanent magnet is present at a relevant point, while no additional adjusting magnet is provided due to the nature of the key. In this respect, the problem of making the field of a permanent magnet in the lock practically ineffective for a specific purpose is not addressed at all in the cited publication.

In order to ensure that a Hall voltage is not generated even without a soft iron coding element and thus a count signal is sent to the assigned counter, the adjusting magnets are provided. These adjusting magnets have the effect that the magnetic field generated by them counteracts the magnetic field generated by the permanent magnets in question, so that in the area in which the Hall generator is arranged, the field strength either has the value zero or is opposite to the field strength caused when the soft iron coding element is inserted . Accordingly, the Hall voltage tapped at the Hall generator is either zero or negative, while a positive Hall voltage is tapped when a soft iron guide piece is present. It is expedient to use Hall generators available on the market which are built into integrated circuits and which, when activated, generate a counting pulse for the assigned counter from the Hall voltage.

Another advantage of the device according to the invention is that the temperature dependency of the registration arrangement is considerably reduced, since the Hall generators are relatively insensitive to temperature within wide limits. This is particularly important in the case of coffee or tea machines in the catering trade, since high temperatures occur in these machines, which in the case of the conventional dispensing and registration devices resulted in the system not working properly and incorrect counting results were obtained. The keys belonging to the smaller locks are accordingly smaller themselves, so that they are not a hindrance when carried. The device is highly insusceptible to failure, which means that the downtimes are low. The components used are inexpensive, so that the overall manufacturing costs of the device are kept low.

In a development of the invention it is provided that the adjusting magnets are made smaller than the duration5

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640 648

magnets and have a smaller distance from the respective Hall generators compared to them.

The different design of the magnets and the asymmetrical arrangement ensure that the desired field profile is achieved in the area of the 5 Hall generators despite the small space requirement for the adjusting magnets.

A particularly simple assembly of the device is achieved in that the distance between the adjusting magnets and the associated Hall probes is adjustable. This measure has the advantage that the selection of the components io and their setting is not critical, since mechanical tolerances can be compensated for and appropriate electrical properties can be taken into account in the desired manner by appropriate setting or adjustment of the adjusting magnets. is

An exemplary embodiment of the invention is explained in more detail below with reference to the drawing. Show it:

1 is a schematic front view of an output and registration device,

FIG. 2 shows a schematic longitudinal section through the lock with output control unit and counters used in the device according to FIG. 1, FIG.

Fig. 3 shows a cross section through a waiter's lock along a line that is indicated in Fig. 3 by III-III, and

4a and 4b show a schematic illustration to explain the course of the field lines in the area of the Hall generators without or with inserted soft iron coding element.

Fig. 1 shows a coffee dispensing and registration device 1, as used for example in cafes or restaurants. The beverage 30 flows from a reservoir 2 through a line 3 via an output control unit 4 and a line 5 adjoining it to an output tap 6. The output control unit is connected to a waiter lock 8 which can be actuated by a key 7. Furthermore, the waiter lock 8 is a set connected by counters 9.

The device works as follows: a cup is placed under the dispensing tap 6, and the key 7, which can also be designed as a ballpoint pen, is inserted into the waiter lock 8 in order to actuate a limit switch 40, whereby the portion dispensing control unit 4 is actuated to let a certain amount of the beverage pass through the lines 3 and 5 from the reservoir 2 and to let it flow into the cup via the dispensing tap 6. When the portion output control unit 4 is switched on, the counter set 9 is also put into a standby state, so that one of the counters can count one step further. Which counter is counted depends on the key 7 inserted in each case, more precisely on the position of one or more soft iron coding elements which are arranged invisibly in the key. Since each waiter has an individual key, in which the respective soft iron coding element is arranged at a different location, a certain counter is counted depending on which waiter operates the device. As a result, it is clear in the final invoice how many servings of coffee each waiter has removed from the device.

2 shows a highly schematic longitudinal section through the waiter lock 8. The lock has a cylindrical hole 10 into which the key 7 must be inserted up to the stop 7 in order to actuate the output control unit 4. Permanent magnets 1 la to 1 lf are arranged side by side on one side of the keyhole. In the area of the end wall of the keyhole 10, a pair of permanent magnets 05 '12' and 12 "is arranged on diametrically opposite sides of the keyhole.

The permanent magnet 12 'forms a differential field plate 13 with two field plates arranged on it. The field plate

13 is connected to the output control unit 4. When the key 7 is completely inserted, a soft iron element 14 bridges the air gap between the permanent magnets 12 'and 12 ", so that a control signal is emitted by the differential field plate 13. The field plates are connected to an associated operational amplifier in such a way that it only then switches through when the guide piece 14 is above the field plate closest to the adjustable stop 7 'No switching operation takes place if the tail unit is above the other field plate or in the middle above both field plates, or if the width of the guide piece extends over both field plates The switching point that is precisely fixed in this way ensures that when the key is inserted, the registration switches are already activated before the system is switched on.

Correspondingly aligned chambers 15 are provided on the side of the permanent magnets 1 la to 1 lf opposite the key hole 10, in which adjusting magnets 16a to 16f are arranged so as to be radially displaceable with respect to the key longitudinal axis. Hall ICs 17a to 17f are arranged at a short distance from the adjusting magnets 16a to 16f towards the keyhole side. The Hall ICs contain voltage stabilization, Hall generator, amplifier, threshold switch and two output stages with an open collector in phase, which are connected in parallel. In addition to the soft iron element 14 arranged at the tip of the key, a soft iron element 18 is provided in the key, which is positioned in the exemplary embodiment shown in FIG. 2 so that it is fully inserted between the Hall generator 17c or the adjusting magnet 16c and the opposite permanent magnet 1 lc lies. The soft gap element 18 bridges the air gap given by the cylindrical configuration of the keyhole 10, so that the field lines emanating from the permanent magnet 11c run through the Hall generator 17c. After activation by the control circuit 4, the Hall IC outputs a counting pulse on the associated counter 9c when a magnetic field passes through the Hall generator. From the above description it is apparent that the limit switch comprising the permanent magnets 12 'and 12 ", the field plate 13 and the soft iron element 14, which is connected to the output control unit 4, is not only responsible for dispensing a portion of coffee , but at the same time via the control circuit 4 causes the individual Hall generators to be brought into the ready position, so that the Hall generator adjacent to a soft iron coding element can emit a counting pulse on the associated counter.

Fig. 3 shows the waiter lock in cross section. As can be seen from the drawing, the soft iron coding element 18 is annular. It is e.g. poured into the plastic key 7 at the relevant point. The key 7 is surrounded by a cover layer 19, so that the position of the coding element 18 cannot be determined from the outside. This makes it difficult to reproduce the key. The adjusting magnet 16c can be moved in the direction of the double arrow P within the chamber 15. The adjusting magnet 16c serves to deflect the magnetic field generated by the permanent magnet 11c while the key 7 is not inserted in the area of the Hall generator 17c and to cause a maximum deflection on the negative side in the Hall generator. The adjusting magnet 16c is set in such a way that only the lines of force of the adjusting magnet 16c penetrate the Hall generator 17c and it therefore emits a negative voltage. All tolerances (electrical, mechanical) can be compensated for by adjusting the adjusting magnet accordingly. Without the adjustment magnets, you would get a positive Hall voltage, which only increased when the key was inserted.

640 648

4th

The function of a Hall generator is generally known and is only to be briefly outlined here. If a (semi) conductor plate through which a current flows is flowed through by a magnetic field which is oriented perpendicular to the direction of current flow, an electrical field 5 is formed in the plate perpendicular to the direction of the current, due to which a Hall voltage Uh on the sides of the plate arises. By detecting the Hall voltage UH it is therefore possible to determine the size or the presence of a magnetic field. In the present exemplary embodiment, the Hall generator is part of an integrated circuit which is particularly suitable for emitting individual control pulses. Activating the circuit causes the current to flow in the semiconductor wafer, and a pulse is emitted when a certain field strength is present in a certain direction. If there is no field or if the field does not have the required direction, no pulse is generated.

To clarify the mode of operation of the device according to the invention, reference should be made in the following to FIGS. 4a and 4b. 4a shows a schematic representation of the field line profile if no piece of soft iron is pushed between the magnets or between the Hall generator and the permanent magnet. The relative position of the permanent magnet 11 and the adjusting magnet 16 means that the resulting magnetic field BL in the Hall generator 17 results in a Hall voltage UH that is zero. The current direction in the Hall generator 17 is perpendicular to the plane of the drawing in the example shown. 4b shows the arrangement with the soft iron coding element 18 inserted. The soft iron coding element 18 bridges the air gap between the Hall generator 17 and the permanent magnet 11, so that a resulting magnetic field Bc penetrates the Hall generator, as a result of which the Hall generator outputs a Hall voltage UH that is greater than zero. By detecting this voltage, a control signal for controlling the associated counter 9c can be generated.

Without the adjusting magnet 16, the Hall generator 17 would be in the field of the permanent magnet 11 and would be penetrated by a magnetic field, even if only weak, which would result in a 40 Hall voltage UH that would be greater than zero. As

As a result, the decision as to whether a soft iron coding element is inserted or not would be extremely critical. In order to ensure that the Hall voltage does not exceed a certain amount when the soft-iron coding element is not introduced, the strength and position of the permanent magnet 11 would have to be determined very precisely, and moreover the keyhole and the key should only be manufactured with extremely small tolerances . However, the adjustment magnet according to the invention ensures that the two states “no soft iron element” and “soft iron element” can be distinguished well, so that incorrect counting is avoided. The properties of the components used and the tolerances are accordingly not critical.

It goes without saying that the polarity of the magnets and, accordingly, the direction of the field, the current flow through the Hall generator and thus the sign of the Hall voltage UH are chosen arbitrarily, the signs can also be chosen the other way round.

The invention is not restricted to the exemplary embodiment described. The key 7 does not need to be cylindrical, for example, but can also have a flat shape; accordingly, the soft iron coding elements 18 are then, for example, disk-shaped. The design of the limit switch for controlling the output unit 4 and for activating the Hall generator 17 is not limited to the solution shown. Other arrangements, for example mechanical limit switches, can also be used. In order to be able to adjust the adjusting magnets 16, other measures can also be taken, for example an eccentric device, adjusting screws or the like can be used. The magnets 1 la to 1 lf and 12 "can be combined into a single continuous magnet. It is also not necessary to assign a single counter directly to each Hall IC. Using a decoder and a different number of coding elements in the keys or A corresponding arrangement of the coding elements allows a large number of counters to be actuated - in the exemplary embodiment above a total of 26 - 1 = 63.

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2 sheets of drawings