GB2091215A - Liquid dispensing apparatus - Google Patents

Abstract

A liquid dispensing apparatus such as is used for dispensing spirits includes an electrical probe for detecting the presence of liquid in a measuring vessel (4) and the departure of the liquid from a given level therein. Each dispensing operation is counted dependent upon a signal derived from the departure of the liquid from a given level in response to the carrying out of a dispensing operation. The probe may include spaced electrodes and the circuit therebetween as completed by the liquid. <IMAGE>

Description

SPECIFICATION Improvements in liquid dispensers The present invention relates to liquid dispensers and more particularly to arrangements for dispensing measured quantities of liquids. Such dispensers are used for dispensing measured quantities of drinks, particularly spirits, in public houses, hotels, restaurants and so on.

In certain circumstances it is advantageous to be able to derive from the dispenser an electrical signal each time a dispense takes place. Such a signal may be used to operate a counter and it follows that if the count so built up is to be acceptable as accurate the apparatus must not deliver signals when the spirit measure is operated when empty.

Arrangements are known in which the mechanism by which the dispenser is operated to deliver a measure of liquid is used to actuate a micro-switch or break a light beam to provide the required signal.

Clearly such arrangements are liable to provide signals when the measure is empty so that the count obtained from such signals is suspect; the count indicates the number of times the mechanism has been operated, not necessarily the number of measures dispensed.

The object of the present invention is to overcome this problem and provide signals which are properly indicative of the number of liquid measures taken out of the dispenser.

According to the invention a liquid dispensing apparatus comprises a vessel arranged to receive a measured quantity of liquid from a supply and valve mechanism associated with said vessel for delivering said measured quantity to an outlet on demand, including an electrical probe arranged to sense the presence of liquid at a given level in said vessel and electronic means connected to said probe adapted to provide a signal in response to the departure of said liquid from said given level when said valve mechanism is operated.

In the apparatus according to the invention in one form the probe includes spaced electrodes positioned so that liquid in the measuring vessel at the given level will complete a circuit connected to said electrodes by providing electrical conductivity between said spaced electrodes.

According to a feature of the invention the probe is connected to a field effect transistor circuit adapted to provide an output signal in response to breaking of the circuit between said electrodes by withdrawal of liquid therefrom.

According to another feature of the invention the signal is employed to operate an electronic counter so as to count successive operations of said valve mechanism by which liquid is withdrawn from the measuring vessel. Alternatively or in addition the signal may be employed to draw attention to the absence of liquid from said measuring vessel.

In order that the invention may be more clearly understood an embodiment thereof will now be described with reference to the accompanying drawings in which: Figure 1 illustrates in elevation a dispensing mechanism to which the invention is applied and Figure 2 illustrates the electrical circuitry employed in association with the device of Figure 1.

The dispenser shown in Figure 1 is of the kind normally used in public houses and clubs for dispensing drinks, usually spirits. The dispenser comprises a body portion 1 from the top of which protrudes a spigot 2 on which an inverted bottle 3 is mounted. Below the body lisa measuring vessel 4 which is usually of glass and constitutes a sight glass which enables the operator to see that the measuring vessel is full. Below the vessel 4 there is provided a valve mechanism 5 operable by a cross-bar 6 to release liquid from the vessel 4through an outlet opening 7 at the bottom of the device. The valve mechanism extends up through the body of the device to operate a closure valve so that liquid is not released from the bottle 3 until the cross-bar 6 has been released after dispensing a drink.A valve at the outlet end of the device is then shut and the measuring glass 4 is refilled from the bottle 3. The whole apparatus is mounted on a bracket 8. Details of the dispensing arrangement are not shown since they are not relevant to this invention.

Mounted in the body 1 are two electrical probes indicated art a and b. The lower ends of these probes extend down into the measuring vessel 4 while the upper ends are brought out in any suitable manner through the body 1 for connection to electrical circuitry.

In the circuit shown in Figure 2 a field-effect transistor 10 is connected to a suitable voltage V through a high resistance R and also to probes a and b in the manner shown. The valve of resistance R is chosen to be high in relation to the resistance of the circuit formed between probes a and b when the vessel 4 is full of liquid. Clearly the liquid with which the apparatus is to be used must have sufficient specific conductivity to enable this relationship to be achieved. The distance between the probes a and b is chosen accordingly.

When the dispenser is operated by raising the crossbar 6, this usually being done by bringing a drinking glass up under the bar to lift it and operate the valve mechanism 5, liquid flows from the vessel 4 thus raising the resistance between probes a and b substantially to infinity. This raised the voltage at the transistor 10 to voltage V thus giving an output signal on the output line 11. This signal will persist until the measuring vessel 4 is again full of liquid.

When the circit between probes a and b is restored in this way the transistor 10 is again switched on and the signal terminates. If there is insufficient liquid available from the bottle 3 to refill the vessel 4 so that the probes a and b are not immersed the signal will remain on and can be used as an indication that a fresh bottle must be applied to the dispenser.

The electrical circuitry may take other forms than that shown. However, the use of a field effect transistor has the advantage that this type of transistor operates with extremely small currents through the liquid so that any significant interference with the liquid in vessel 4 is prevented. Where this is not important other types of transistor or other suitable electronic device may be used.

From the above description it will be clear that if the signals delivered to the load over line 11 are used to operate a counter only those attributable to the vessel 4 being emptied of liquid will be counted and therefore the count will be a true representation of the number of drinks dispensed and will not be affected by operation of the valve mechanism when the bottle is empty or no further liquid supply is available to the dispenser.

Claims (9)

1. Liquid dispensing apparatus comprising a vessel arranged to receive a measured quantity of liquid from a supply and valve mechanism associated with said vessel for delivering said measured quantity to an outlet on demand, including an electrical probe arranged to sense the presence of liquid at a given level in said vessel and electronic means connected to said probe adapted to provide a signal in response to the departure of said liquid from said given level in response to operation of said valve mechanism.

2. Liquid dispensing apparatus as claimed in Claim 1 wherein said probe includes spaced electrodes so positioned within said vessel that a circuit between said electrodes is completed through said liquid when said liquid reaches said given level.

3. Liquid dispensing apparatus as claimed in Claim 2 wherein said electrodes are spaced around the perimeter of said vessel at said given level at a distance apart such that a conductive path completed between them by the presence of liquid in said vessel at the given level has an electrical resistance below the maximum at which said electronic means is operable.

4. Liquid dispensing apparatus as claimed in Claim 1,2 or 3 wherein said electronic means includes a field effect transistor arranged to be maintained conductive in a circuit including a resistive path through said liquid when said liquid reaches the level sensed by said probe.

5. Liquid dispensing apparatus as claimed in Claim 4 wherein said electronic means includes counting means arranged to count successive dispensing operations from said vessel.

6. Liquid dispensing apparatus as claimed in Claim 4 or 5 wherein said electronic means includes signalling means arranged to signal the absence of liquid from said vessel.

7. Method of monitoring a liquid dispensing operation consisting of a succession of deliveries of measured quantities of the liquid from a supply and comprising filling a measuring vessel with liquid from said supply and delivering the contents of said vessel to an outlet on demand, the method comprising sensing the departure of the level of liquid in said measuring vessel from a given level to provide an indication of a measuring operation and counting the measuring operations so sensed.

8. Liquid dispensing apparatus constructed and adapted to operate substantially as hereinbefore described and illustrated in the accompanying drawing.

9. Method of monitoring a liquid dispensing operation substantially as hereinbefore described.