GB2055348A - Flow metering dispenser system - Google Patents

Abstract

A flow metering dispenser system for dispensing alcoholic beverages or the like comprises a dispensing unit (4) having a control valve (16), a container (2) for storing the liquid to be dispensed and a metering unit (6) which employs an impeller (28) which is rotated directly by the liquid to be dispensed and which actuates switch means to operate the control valve (16) to close the valve when the required quantity of liquid has been dispensed. <IMAGE>

Description

SPECIFICATION Flow metering dispenser system The present invention relates to a flow metering dispenser system for dispensing alcoholic bever ages.

Two types of beer dispensing system are in com mon use. Firstly, there are the free flow systems and secondly, there are the metered dispenser systems.

One requirement is common to both systems, namely how quickly the required quantity of beer or lager can be dispensed.

In the free flow system, the liquid to be dispensed is pumped by hand or forced under pressure from a storage container to a dispenser unit. The quantity delivered is controlled manually by the bar person.

Typically a glass is filled either to the brim orto a calibration mark on the glass. If too much beer is delivered then the seller will be losing money. Conversely if too little beer is dispensed the customer will object and time will be wasted topping up the glass. Additional problems arise when the beer fobs excessively, for example beer is wasted in filling a glass to the brim if a lot of froth is generated while dispensing or valuable time is wasted topping up, when the head has subsided. However, steps are usually taken to prevent fobbing in the lines of both types of system. Also with the force flow system the bar person has to attend to the pouring and cannot therefore be preparing other drinks in the same order. Because time is wasted with the free flow system it is losing popularity to the metered system.

In a known metered dispenser system the beer or lager is forced under gas pressure or by pump to the dispenser unit and passes by way of a metering unit.

A typical metering unit comprises a measuring chamber having a volume of exactly half a pint and which has two connections entering the chamber. A flexible diaphragm inside the chamber separates the two connections preventing flow through the chamber from one connection to the other. A pair of conduits lead from the two connections to a control valve and a further pair of conduits lead from the control valve to a storage container and a dispenser head respectively. The control valve may typically be a 3 position 2 way valve. In a central position all the conduits are closed off. In a first displaced position one of the conduits from the chamber is connected to the storage container and the other conduit is connected to the dispenser head. In a second displaced position the connections from the chamber to the storage container and dispenser head are reversed.

Initially with the control valve in the central position the measuring chamber is full of beer and the diaphragm is displaced to one side. When the control valve is actuated to dispense beer the control valve assumes a first position and beer under pressure flows from the storage container, displaces the diaphragm filling the chamber created as the diaphragm moves and at the same time displacing a measured quantity of beer which is dispensed from the dispenser head. A switch actuated when the diaphragm is fully displaced operates the control valve returning it to the central position and closing all the connections.

Because such metered systems employ a chamber containing only half a pint it is necessary to perform the operation twice to deliver a pint measure. This introduces a delay which increases the time taken to dispense the required measure. To avoid the delay in delivery various modifications of the basic system have been used. For example double systems have been introduced which enable two half pints to be dispensed simultaneously. However, such a system is naturally more expense than the half-pint system.

Other modifications to the basic system have introduced more complex switching methods and compressed air operated diaphragms in orderto speed up the delivery. However, these systems are also more complicated as well as more costly and are prone to breakdown.

A further disadvantage of a metering system incorporating a chamber containing the required measured volume is that it is not readily possible to convert it should the standard measure of half a pint be replaced by the equivalent metric measure in litres. It would be necessary to replace the entire unit. This would prove very expensive and so the changeoverto metric is resisted by the trade.

It is an object of the present invention to provide a metered dispenser system which will dispense a full pint of beer quickly without delay. It is a further object of the system to avoid using complicated multi-position control valves and to provide a metering unit which can be easily converted from English to metric quantities.

According to the present invention there is provided a flow metering dispenser system, for dispensing a predetermined quantity of liquid, comprising a dispenser unit having a control valve controlling the flow of liquid from the dispenser unit, a container for storing liquid remote from the dispenser unit, a flow path between the container and the dispenser unit, means for applying a pressure gradient to the flow path and a metering unit having an impeller which is displaceable rotatably by the liquid to be dispensed, switch means controlled by the movement of the impeller, to trigger closure of the control valve when the required quantity of liquid has been dispensed.

In a preferred arrangement the impeller has a plurality of circumferentially spaced radially extending vanes, and is attached to a spindle which extends sealingly through one end face of the metering unit.

Cam means remote from the impeller driven by the spindle and comprising at least one disc which actuates at least one electric of switch. The switch is provided in a circuit with a solenoid valve for controlling the control valve of the dispenser unit to close the control valve when the required quantity of liquid, as measured by rotation of the cam means, has been dispensed.

The present invention will now be described further, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a diagrammatic view of a metered dis penser system according to the present invention; Fig. 2 is a sectional view of one embodiment of a metering unit of the present invention; Fig. 3 is a section on X-X of Fig. 2; and Fig. 4 is a sectional view of another embodiment of a metering unit of the invention omitting the impeller.

Fig. is a diagrammatic view of a flow metering dispenser system having a flow path comprising a container 2, for holding the liquid to be dispensed, a dispenser head 4, means for applying a pressure gradient to the flow path, a metering unit 6 and interconnecting pipework 8. The container 2 is typically a beer or lager barrel and the means for applying the pressure gradient to the flow path is either a CO2 gas cylinder 10 (as illustrated) alternatively it may be an air compressor or drive motor. A pressure reducing valve 12 is used in conjunction with the gas cylinder to adjust the pressure in the line. However, this is not always essential. The dispenser head 4 has an outlet tap 14 which is controlled buy a solenoid operated control valve 16.As illustrated an anti-fob unit 18 is incorporated in the system; additionally a cooler may be incorporated although not shown.

As will be seen more clearly with reference to Figs.

2 and 3 one embodiment of the metering unit 6 comprises a housing 20 having a circular chamber 22 therein. An inlet 24 and an outlet 26, arranged tangentially to the chamber and at right angles to each other, enable the liquid to be dispensed to flow into and out of the metering unit. A non-return valve 30 (shown in Fig. 1) is provided in the flow path upstream of the metering unit and conveniently isolating valves (not shown) are provided on either side of the metering unit for ease of servicing. The housing 20 of the metering unit may be a plastics moulding or an alloy casting. Other materials suitable for use with beer or lager may be used. An impeller 28, having a plurality of radially extending circumferentially spaced vanes 32 is rotatably disposed in the chamber 22.The impeller 28 is secured to a spindle 46 which is journalled in bearings 34 and which rotates with respect to the housing. The spindle extends from one end face of the metering unit housing 20 and passes through a seal 40 which prevents loss of liquid from the system and which is contained in a recess 38 in the housing.

As shown the spindle 46 is provided with cam means 42 in the form of a disc 44 which is nonrotatably secured to the spindle by a key or such like.

The disc is clamped against a shoulder 50 of the spindle by a nut 52 threadingly engageable with the spindle. In an alternative arrangement the disc is geared down rather than a direct drive as shown in Figs. 2 and 3. Such a modified arrangement will be described below with reference to Fig. 4.

The periphery of the disc 44 of Fig. 2 is profiled so as to operate an electric switch 60, preferably a micro switch. The micro switch is of the type provided with an arm 62 pivoted aboutthe body of the switch, the free end having a roller 64 which abuts the periphery of the disc 44. The switch 60 is con nected in an electrical circuit with a solenoid 52 operating the control valve 16 in the dispenser head 4. A push switch 54 is connected in circuit with the solenoid 52 and is provided on or near to the dis penser head 2.

When it is required to dispense a measured quantity of beer or the like the push switch 54 at the dispenser head 2 is operated. This signals the solenoid to open the control valve and the liquid which is subject two a pressure gradient commences to flow through the pipes and out of the dispenser tap. The flow through the metering unit causes the impeller 28 to rotate, which in turn drives the cam means 42.

Before delivery commences the position of the disc 44 is such that the circuit in which the micro switch 60 is connected is broken. When rotation of the disc commences upon delivery the profile of the disc displaces the movable leverofthe micro switch and makes the circuit which now supplies power to the solenoid 52 to keep open the control valve 16. The disc revolves in proportion to the liquid delivered and conveniently is calibrated so that one revolution represents a delivery of half a pint. The profile of the cam is such that when one revolution has been completed the micro switch is operated to break the circuit and so close the control valve and shut off the flow from the dispenser.

Zit is envisaged in a preferred embodimentthattwo discs would be driven by the impeller. A first disc would be calibrated for half a pint and a second disc would be calibrated for one pint. Two micro switches, one associated with each disc, would be provided and a two position switch located adjacent the dispenser head and selectable by the bar person would be used to bring into operation the appropriate micro switch depending on whether a half pint or afull pintwas required.

A feature of the invention is the ease with which the metering disc can be changed. Thus, if it is required to convert to metric measurements, the same impeller can be utilised and only the discs would have to be replaced by recalibrated metric discs. The discs and micro switches would be mounted in a self contained disc housing 78 which could be sealed to avoid tampering. As shown in Fig.

4 two discs 80, 82 are secured to a spindle 84 which is journal led for rotation in the disc housing, bearings 86 being provided for this purpose. In the arrangement shown the spindle 84 has a gear 88 which is driven by way of a mating gear 90 secured to a gear shaft 92 which is journalled for rotation in bearings 92 in the disc housing 78. The gear shaft 92 takes its drive from the impeller spindle (not shown) to which it is keyed or otherwise non-rotatably secured.

The discs 80, 82 are of different sizes and are calibrated accordinglyforthe required measures. A pair of micro switches 94, 96 are attached to the disc housing via individually adjustable plates 98, 100 which permit fine adjustments to be made in order to calibrate the equipment accurately. As with the previously described embodiment each disc is provided with a profiled cam surface for operating its micro switch. Electrical connections lead from the micro switches to contacts provided on the exterior of the disc housing. This enables the switches to be wired into the circuit without opening the disc housing. A single disc may be adapted to control the delivery of a half pint or a full pint in place of the two discs of the arrangement described; for example, the cam profile may be on the end face of the disc rather than on the periphery. This would enable one disc to operate two micro switches, the cam surfaces being positioned concentrically on the disc.

It is further envisaged that the system according to the invention may utilise a sensing system whereby the rotation of the impeller controls the switching position without the need for a cam driven directly from the impeller. For example, if the meter housing was made from an opaque plastics material and the impeller made from a non-opaque material, a light sensing circuit accompanied by an appropriate "black box" could count the number of revolutions of the impeller and trigger the solenoid operated control valve to close when the required quantity of liquid had been delivered.

Claims (8)

1. A flow metering dispenser system, for dispensing a predetermined quantity of liquid, comprising a dispenser unit having a control valve controlling the flow of liquid from the dispenser unit, a container for storing liquid remote from the dispenser unit, a flow path between the container and the dispenser unit, means for applying a pressure gradient to the flow path and a metering unit having an impeller which is displaceable rotatably by the liquid to be dispensed, and switch means controlled by the movement of the impeller to trigger closure of the control valve when the required quantity of liquid has been dispensed.

2. A dispenser system as claimed in claim 1, in which the impeller has a plurality of circumferentially spaced radially extending vanes which are attached to a spindle which is rotatable with respect to the metering unit.

3. A dispenser system as claimed in claim 1 or 2, in which the impeller drives cam means positioned remote from the impeller.

4. A dispenser system as claimed in claim 3, in which the cam means comprises at least one profiled disc which actuates at least one electrical switch, the switch being connected in an electrical circuit to trigger a solenoid valve of the control valve.

5. A dispenser system as claimed in claim 3, in which the cam means comprises a disc having an end face which carries two profiled tracks which are disposed concentrically with respect to one another and in which each profiled track actuates an electri cal switch which operate the control valve.

6. A dispenser system as claimed in any of claims 3 to 5, in which the cam means is driven by the spindle, which extends sealinglythrough an end face of the metering unit, by way of gearing.

7. A dispenser system as claimed in claim 1 or 2, in which the switch means comprises a light emitter and a light detector and in which the impeller interrupts a light beam between the light emitter and the lightdetectorto act as a pulse counting circuit which operates the control valve when a predetermined number of coating pulses have occured.

8. A flow metering dispenser system constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.