GB2287013A

GB2287013A - Liquid metering system

Info

Publication number: GB2287013A
Application number: GB9401997A
Authority: GB
Inventors: John Brian Hall
Original assignee: Guinness Brewing Worldwide Ltd
Current assignee: Guinness Brewing Worldwide Ltd
Priority date: 1994-02-02
Filing date: 1994-02-02
Publication date: 1995-09-06
Anticipated expiration: 2014-02-02
Also published as: GB2287013B; GB9401997D0

Abstract

A liquid flow system primarily for dispensing beverage has a tap 4 by which beverage is drawn on demand through pipe 6 from a bulk supply. The pipe 6 includes a chamber 10 having a member 11 which is displaced during beverage flow to permit light from an emitter 12 to be applied through the beverage to a light sensor 13 that provides a signal to a microprocessor 17 actuating a timer 17A. Following a predetermined time during beverage dispensing consistent with a predetermined volume of beverage being dispensed, the microprocessor 17 actuates a stamp 21 which is applied to a customer record card 24. The card 24 forms part of a sales promotion whereby when sufficient volumes of beverage purchased have been recorded, the card can be submitted for a reward. In a modification the card 24 includes a magnetic stripe and the stamp 21 is replaced by an electronic head for writing to the magentic stripe and recording predetermined volumes of beverage purchased. The sensor 13 is responsive to variations in intensity of light applied thereto through the beverage so that the characteristics of the sensor 13 can be predetermined for a predetermined beverage which controls actuation of the stamp 21 only when that predetermined beverage is being dispensed. <IMAGE>

Description

TITLE "A liquid flow system" TECHNICAL FIELD & BACKGROUND ART The present invention relates to liquid flow systems and is primarily, but not essentially, concerned with systems for dispensing beverage (such as lager, ale or stout) on demand either from a reservoir (such as a cask or keg) of the beverage or other bulk source (such as where the beverage is prepared on demand by mixture of a beverage syrup with water as is often the case with so-called "soft drinks").

It is recognised that on-sales retail outlets for beverage such as beer frequently have a sales counter with many beer dispensing taps for various brands and different brewers. It is also recognised that brewers compete with each other both by advertising and promotion schemes to attract customers to purchase their particular beverage.

It is an object of the present invention to provide a liquid flow system which may be used for the dispensing of beverage or other liquid and particularly lends itself to form part of a promotion scheme for attracting consumers/customers to the particular beverage or other liquid that is being dispensed.

STATEMENT OF INVENTION & ADVANTAGES According to the present invention there is provided a liquid flow system comprising a valve which is adjustable to an open or a closed condition to control liquid flow therethrough, control means for determining a predetermined volume of liquid flowing through said valve when in its open condition, and record means responsive to said control means providing an identifiable record automatically in response to flow of said predetermined volume of liquid through the valve.

As previously mentioned, the present invention was primarily developed for dispensing beverage, principally fermented beverage (such as stout, ale, lager or cider, or non-fermented beverage (such as so-called soft drinks) where the beverage is supplied through what is typically a bar mounted dispensing tap and derived from a bulk supply.

For convenience, the invention will be discussed hereinafter with reference to the dispensing of beverage although it is to be appreciated that the invention may be applied to flow systems for liquid other than beverage.

By the system of the present invention it is envisaged that when a predetermined volume of beverage, say 1 pint (568 cc), is dispensed through the valve or dispensing tap for a particular customer, the control means responds to actuate record means which provides an identifiable record for that customer that the predetermined volume of a particular beverage has been dispensed/purchased. The identifiable record may be applied to a log that is personal to and is retained by the customer as a record of the number of predetermined volumes of the particular beverage that the customer has purchased.By providing such a record on a personal log, the system is particularly suitable for use in a scheme which promotes sale of the particular beverage whereby when a customer log records the purchase (through one or more similar dispensing systems) of a predetermined number of the predetermined volumes of the particular beverage, that log may be exchanged for various items or other rewards provided by the supplier of the beverage, usually a brewer. Normally with such a sales promotion scheme it can be expected that the larger the number of predetermined volumes of the particular beverage recorded on a customers personal log, the larger will be the value of the item or reward for which that log (or several such logs that the customer may have accumulated) can be exchanged.The log is conveniently in the form of a card that is conveniently and normally retained by the customer to be presented when ordering the particular beverage so that the card can be applied to the system and have a record of purchasing a predetermined volume of the beverage applied thereto by the record means of the system.

The card may, for example, have a stamp applied thereto for each predetermined volume of beverage that the customer purchases and which stamp is peculiar to the supplier of the beverage. To alleviate abuse of the promotional scheme by counterfeiting the particular form of stamp, it is preferred that the stamp is applied with a security ink the characteristics of which are known only to the supplier of the beverage so that such supplier can readily identify authentic stamps. Alternatively the log may be in the form of a card or similar member having a magnetic region (such as a stripe) the electro-magnetic characteristics of which are varied by the record means for each predetermined volume of beverage that is purchased by the customer. The magnetic region can therefore provide a memory from which an accumulated number of predetermined volumes of the beverage purchased may be read.By this latter proposal it is possible for the system to include a facility to write data to the memory of the magnetic region for the purpose of recording purchase of a predetermined volume of the beverage and also to read data from the memory of the magnetic region for the purposes of providing an instant indication to the customer of the number of predetermined volumes of the beverage that have been accumulated on the record card.

As a further feature to attract custom for sales of the beverage, the system may include a counter which counts the number of predetermined volumes of the beverage which are dispensed through a particular valve or dispensing tap and when that number reaches a predetermined number, an appropriate display is indicated (preferably during dispensing of the beverage) so that the customer at that instant may be rewarded as appropriate. For example, the dispensing system may be set so that at each hundred pints of beverage successively dispensed from a particular tap, a display (such as illumination of a display panel on that tap) is actuated to indicate to the customer that the hundredth successive pint is being dispensed and is free.

Following the dispensing of that hundredth pint or other number as predetermined, the counter would reset to zero and commence recounting as the successive pints are drawn.

Having this sales promotion facility in mind, the present invention further provides a liquid flow system comprising a valve which is adjustable to an open or a closed condition to control liquid flow therethrough; control means for determining a predetermined volume of liquid flowing through said valve when in its open condition; counter means which counts successively each said predetermined volume of liquid that flows through said valve as determined by the control means, and signalling means that responds to a predetermined number of said successive predetermined volumes of liquid being counted to provide an indication of that attainment.

Preferably the control means responds to a predetermined volume of beverage flowing through the valve when in its open condition under control of a timer that is actuated when dispensing of the beverage commences and which after a predetermined interval of dispensing consistent with dispensing of the predetermined volume of beverage, causes the control means to actuate the record means. Desirably the timer is sensitive to intermittent dispensing of beverage by successive openings and closings of the valve so that the record means will be actuated only in response to the predetermined volume of beverage being dispensed intermittently. For example a customer for the beverage may frequently purchase two separate half pints of the beverage and nevertheless require a record on the personal log of an indication that one pint has been purchased.Desirably therefore the timer will permit two separate half pints to the dispensed and at or towards the dispensing of the second half pint cause the record means to be actuated to indicate on the customer's personal log that a pint of the beverage had been purchased. With this in mind it is preferred that the control means comprises an override for the timer which override determines a maximum period that is permitted for dispensing the predetermined volume of beverage intermittently by opening and closing of the tap (that is intermittent starting and stopping of beverage flow). If the maximum period determined is exceeded, the record means is not actuated and the timer resets.For example, the override means may permit, say, two minutes within which a pint of beverage is to be dispensed and such period should permit adequate time for dispensing a pint of the beverage as two separate half pints. By use of such an override facility it may be ensured that if the predetermined volume of beverage is, say 1 pint as aforementioned, it is unlikely that two separate half pints can be dispensed one for each of two separate customers within the maximum permitted period and the second customer would not therefore have his personal log marked or otherwise altered to indicate purchase of a pint of the beverage when in fact that customer only purchased a half pint.

To alleviate abuse of the system, particularly when used to provide a personal log of predetermined volumes of beverage purchased by a customer for sales promotion as previously discussed, it is preferred that the system comprises beverage sensing means that is responsive to predetermined characteristics of a particular beverage which is intended to be dispensed by the system and responds to those characteristics to permit actuation of the record means solely when the predetermined volume of the intended beverage has been dispensed.For example, in the absence of the aforementioned beverage sensing means, a brewer may instal the system for dispensing a particular brand of beer but if, following such installation, a different beverage is dispensed through the system, personal logs provided by the brewer for customers could nevertheless be logged as a record to indicate, falsely, purchase of predetermined volumes of the intended beverage and eventually rewarded by the brewer (whereas in fact the sales of the beverage dispensed were to the benefit of a third party).Also in the absence of the beverage sensing means, customers personal logs could be recorded as indicating purchase of the intended beverage by dispensing water through the system during cleaning! The beverage sensing means may, for example, sense the specific gravity of the beverage in the system and when a particular specific gravity is detected consistent with that of the intended beverage, permit actuation of the record means. It is recognised that many beverages differ widely in their translucency or light transmission characteristics, for example, a beverage such as stout will usually be dark or black to present low light transmission characteristics as compared with lager which is usually golden and present relatively high light transmission characteristics whilst water may be regarded as transparent.With this in mind the beverage sensing means conveniently and preferably comprises a light emitting device that transmits light (which may be in the visible spectrum or otherwise) through the liquid that is being dispensed to a light sensitive device or sensor, the characteristics of which sensor vary in accordance with variations in the intensity of the light which it receives through the liquid. The characteristics of the light sensitive device will be predetermined for light it receives through a particular beverage that is intended to be dispensed through the system and the control means is arranged so that it responds to those predetermined characteristics of the light sensitive device to permit actuation of the record means when a predetermined volume of the intended beverage has been dispensed.In the absence of the predetermined characteristics of the light sensitive device indicative of the intended beverage, the record means is maintained inactive irrespective of the volume of beverage that is dispensed. Conveniently the light sensitive device is a light dependent resistor, the resistance of which varies depending upon the intensity of light which it receives. The light dependent resistor may provide a high resistance when no light is detected, a medium resistance when low intensity of light is detected (as may occur by a light transmitted from the emitting device through dark beer such as stout) and a low resistance when high light intensity is detected (as may occur if a light beer such as lager or water is being dispensed through the system).By arranging the control means so that it will respond to permit actuation of the record means when the light dependent resistor has, say, a medium resistance it may be ensured that the record means can be actuated only when a predetermined volume of dark beer or stout of the appropriate translucency is being dispensed.The beverage sensing means may also serve as a liquid flow indicator by having a flow responsive member in the beverage which member is preferably opaque and, in the absence of liquid flow through the system adopts a first position in which it impedes a light beam from the light transmitting device through the liquid to the light sensor and, when liquid flow commences in the system, is displaced by such flow to a second position in which the light responsive sensor receives light from the emitter through the liquid in the system unimpeded by the member to vary the characteristics as aforementioned of the light responsive sensor.The liquid flow responsive member may act as a switch that provides a signal from the light responsive sensor to indicate that liquid flow has commenced and effectively switches on the control means and timer (preferably to start timing the maximum period permitted as aforemetnioned for dispensing beverage intermittently) as well as ensuring that the control means will only permit actuation of the record means when the characteristics of the light sensitive device are such as to indicate that an intended beverage is flowing through the system. The flow responsive member of the beverage sensing means is conveniently mounted in an upwardly extending chamber to be displaceable upwardly from its first position to its second position as fluid flow commences so that in the absence of such flow the member will fall under gravity to adopt its first position. It will be appreciated however that the flow responsive member may be displaceable between its first and second positions other than in a vertical direction, for example the member may be displaceable horizontally in response to liquid flow through the system and be spring biased to adopt its first position in the absence of liquid flow.

Still further according to the present invention there is provided a liquid flow sensor comprising a chamber through which liquid is to flow; a light emitting device for applying a light beam through liquid in the chamber to a light sensitive device; a flow responsive member in the chamber that is displaceable between a first position in which it impedes said beam and a second position in which the beam is unimpeded to be applied to the light sensitive device, said member adopting its first position in the absence of liquid flow through the chamber and being displaced to its second position in response to liquid flow through the chamber; said light sensitive device being responsive to variations in light intensity of the beam applied thereto and wherein control means is provided that responds to predetermined characteristics of the light sensitive device which characteristics indicate liquid flow through the chamber when the member is in its second position and the liquid in the chamber has predetermined light transmission characteristics.

DRAWINGS One embodiment of the present invention as applied to a beverage dispensing system will now be described, by way of example only, with reference to the accompanying illustrative drawings, in which: Figure 1 illustrates a bar unit having a dispensing tap for the system; Figure 2 schematically illustrates the principal features of the bar unit shown in Figure 1; Figure 3 illustrates a customer log suitable for use with the bar unit of Figures 1 and 2 in a scheme for promoting sales of the beverage dispensed by the system, and Figure 4 is a schematic illustration of a bar unit similar to that shown in Figure 2 and modified for use with a different type of personal log and to provide additional features for use in a promotion scheme for sale of the beverage.

DETAILED DESCRIPTION OF DRAWINGS The system illustrated is intended for dispensing beverage, conveniently considered as stout, at an on-sales retail outlet in response to customer requests and has a bar unit 1 secured to a sales counter 2. The unit 1 has a compartment 3 mounted on which is a dispensing tap 4.

The tap 4 is of conventional form having an on/off valve (not shown) adjustable by a handle 5 to control flow of beverage from a delivery pipe 6 to an outlet or dispensing nozzle 7. The pipe 6 extends to the tap 4 by way of the compartment 3 and from a bulk supply (not shown) of the stout. Conveniently the supply is a pressurised cask so that stout will be dispensed from the nozzle 7 by adjustment of the handle 5 in conventional manner.

Located in the compartment 3 and closed thereby to extraneous light is a liquid flow sensor 8 having a body 9 that is conveniently formed of clear acrylic, and provides a substantially vertical elongated chamber 10. The chamber 10 is included in the delivery pipe 6 to the dispensing tap 4 and is connected at its upper end to communicate with that tap and at its bottom end to communicate with the stout supply. Located in the chamber 10 is an opaque flow responsive member 11. In the absence of liquid flow through the chamber 10 to the tap 4 the member 11 is seated in a first position at the bottom of the chamber 10 and when liquid flows through the chamber 10 to the tap 4, the member 11 is displaced by such flow to a second position towards the top of the chamber (as indicated at llA).When liquid flow through the chamber ceases, the member 11 falls under gravity to adopt its first position. Mounted on or in the wall of the body 9 towards the bottom of the chamber 10 and at positions on directly opposite sides of the chamber 10 is a light emitting device (LED) 12 and a light dependent resistor (LDR) 13. The resistance of the LDR 13 is variable in response to variations in the intensity of light applied thereto, typically the LDR will have a low resistance when subjected to high light intensity, a medium resistance when subjected to medium light intensity and a high resistance when subjected to zero or very low light intensity. The LED 12 is mounted to direct a light beam to the LDR 13 through the chamber 10 and the compartment 3 provides a light resistant enclosure so that the LDR 13 is, in substance, responsive solely to light applied thereto from the LED 12.It will be seen from Figure 2 that when the flow responsive member 11 is in its first position (indicating no beverage flow) that member 11 breaks the beam from the LED 12 to the LDR 13 so that the latter is subjected to zero or minimal light intensity and presents say, a high resistance. It will also be seen from Figure 2 that during liquid flow through the chamber 10 and when the flow responsive member is displaced to its second position llA, the full beam from the device 12 is applied to the LDR 13 and the intensity of that beam will vary depending upon the light transmission characteristics of the beverage that flows through the chamber 10 so that the LDR may provide say, a medium resistance or a relatively low resistance.

Mounted on the compartment 3 and forming part of the bar unit 1 is a housing 15 having a facia panel 16 directed over the sales counter 2. The panel 16 can conveniently carry a Trade Mark for the beverage which is to be dispensed through the unit or other informatIon that may be presented to a customer. The housing 15 contains an electronic control system comprising a microprocessor 17 connected to an electrical power source 18 and having a comparator window circuit 19. The microprocessor 17 controls energisation of a solenoid 20 for displacement of a die or stamp 21. In addition the microprocessor controls energisation of a light emitting device 22 for illumination of the facia panel 16. The housing 15 has a slot 23 for reception of a card 24.When positioned in the slot 23, the card 24 is located adjacent to the stamp 21 so that when the stamp is displaced by energisation of the solenoid 20 it will apply a marking to a face of the card 24. As shown in Figure 3, the card 24 conveniently has on its face an array of windows 25 (of which ten are illustrated) so that by appropriate positioning of the card 24 in the slot 23 any one of the windows 25 may be marked by the stamp 21, for example to apply an asterisk or other design thereto as indicated at 26. For such marking of the card in each of the windows 25, an arrow 27 is provided on the top of the housing 15 for convenience of aligning a particular window 25 with the stamp 21 (with the card in either one orientation in the slot 23 or in a relatively inverted orientation).

The beverage dispensing system is particularly suitable for use in a scheme for promoting sales of the particular beverage, say stout as previously mentioned, that is dispensed through the system. In such a scheme a customer for the beverage will be provided, usually by the brewer, with a card 24 which is intended to provide a log of the number of predetermined volumes of beverage, say each of one pint, that the particular customer has purchased and the purchase of each such pint is recorded on the card 24 by the application of a stamp 26 to the customers log card. When the customer has accumulated sufficient stamps 26 on the card, say 10 stamps, that card (or an accumulated number of completed cards) may be submitted to the brewer in return for an appropriate gift or other reward.To alleviate counterfeiting of the stamps 26 on a customers record card 24, it is preferred that the stamp 21 utilises a security ink for applying the stamp 26 so that such ink can readily be identified by the brewer to authenticate the markings 26 and reject counterfeit markings.

The LED 12 and LDR 13 are connected to the comparator circuit 19. As previously mentioned, a particular beverage which flows through the chamber 10 will have predetermined light transmission characteristics and for such a beverage the effect of these characteristics on the LDR 13 in response to the intensity of light applied thereto through the beverage from the device 12 may be predetermined. In the present example for dispensing stout, when stout is flowing through the system the light intensity applied to the LDR 13 will provide a predetermined medium resistance (as compared with a high resistance when there is no stout flow through the system and the light beam is impeded by the member 11 and a relatively low resistance if clear water flows through the system as will occasionally be necessary for cleaning the delivery pipe).The circuit part 19 of the microprocessor detects variations in the resistance of the LDR 13 and provides various signals the microprocessor 17 indicative of when such resistance (a) is the predetermined medium resistance corresponding to the required stout flowing through the system or (b) is a high resistance indicating that the member 11 is in its first position and there is no liquid flow through the system or (c) is other than (a) or (b) indicating that liquid may be flowing through the system other than that of the intended stout.

In effect the liquid flow sensor 8 acts as a switch whereby when dispensing of the intended stout commences and the flow of such stout displaces the member 11 into its second position llA and light of the appropriate intensity is applied through the stout to the LDR 13, a signal from the circuit 19 for the microprocessor is indicative that dispensing of the intended stout has commenced. This signal causes energisation of the light emitting device 22 for illumination of the facia panel 16 to indicate to the customer that dispensing has commenced and also actuation of a timer 17A which forms part of the microprocessor 17.

In a typical stout dispensing system a pint of stout will be dispensed in say twenty five to thirty seconds of continuous flow through the nozzle 7. However, in practice the flow of stout in dispensing a pint is unlikely to be continuous so the actual dispensing time may take thirty to fourty seconds as the control tap is opened and closed intermittently to control the charging of a glass in the latter stages of dispensing a pint.With this in mind, when dispensing commences and the timer 17 is actuated, the electronic system including the microprocessor 17 is maintained energised for a predetermined period, say, two minutes, which is sufficient time to ensure that a pint of stout can be dispensed with acceptable intermittent opening and closing of the tap 4 and during such intermittent opening and closing of the tap 4 the timer 17A records the actual period during which the stout is dispensed (irrespective of the fact that the flow responsive member may intermittently move between its first and second positions). During the aforementioned predetermined period of say two minutes permitted for dispensing the predetermined volume of stout, the facia panel 16 is maintained illuminated.When the timer 17A indicates adequate time has elapsed for actual dispensing or flow of the stout, say twenty three seconds, to ensure that a pint will be dispensed, the microprocessor 17 signals the solenoid 20 to actuate the die 21 to apply a stamp 26 to the customers record card 24. Following such stamping the die head 21 and the counter reset in preparation for a further timing and recordal. The microprocessor 17 includes an override whereby when the aforementioned predetermined period of, say, two minutes, within which to achieve dispensing of the predetermined volume of stout to receive a stamp 26 has elapsed and such volume of stout is not dispensed, the timer 17A resets in preparation for, or to recommence, timing for the dispensing of further beverage.If beverage is not being dispensed at the end of the predetermined period, the electronic system may be de-energised until the flow of stout recommences for further dispensing. By the provision of the aforementioned predetermined maximum period permitted for dispensing a predetermined volume of stout to achieve a record stamp and of the override facility, it is possible to alleviate mis-use of the system in a sales promotion scheme.For example if a first customer purchases less than the predetermined volume of stout required to achieve a stamp 26, say a half pint rather than one pint, then the stamp 26 will not be recorded for that first customer although the timer 17A will have commenced and if a second customer then purchases a half pint of stout it is unlikely that the two separate customers can be attended to within the predetermined period of two minutes so the timer 17A will be reset and the second customer will not have a stamp 26 applied to his record card 24 (which would otherwise falsely attribute to that second customer the purchase of a pint to gain from the purchase of the first customer).However, the predetermined maximum period of, say, two minutes for dispensing a pint is likely to be adequate to permit a single customer to be attended to who purchases two separate half pints so that towards the end of dispensing of the second half pint within the two minute period the solenoid 20 will be energised for the die 21 to apply a stamp 26 to that customers record card 24.

The beverage dispensing system also alleviates abuse of the sales promotion scheme previously described by the facility of the flow sensor 8 and the electronic control system therefor to recognise predetermined light transmission characteristics of the beverage that .is intended to be dispensed through the system for use with the promotional scheme, in the present example, stout. As a consequence, in the event that a beverage other than the intended stout, say lager having high light transmission characteristics is dispensed through the system, the comparator circuit 19 responds to the "unacceptable" resistance indicated by the LDR 13 and signals the microprocessor 17 to maintain the solenoid 20 inactive and ensure that no stamp 26 is applied to a customers record card irrespective of the volume of beverage that is dispensed through the system. This also applies if water is passed through the dispensing system for cleansing purposes.

Figure 4 shows a modification of the stout dispensing system as previously described with reference to Figure 2 and- which permits use of a different form of log for recordal of predetermined volumes of stout purchased by a customer and has additional facilities for use in promoting sales of the beverage. In particular in Figure 4 the customer log is in the form of a card 24A having a magnetic stripe (not shown) which is received within the slot 23 when the customer purchases a pint of stout. In Figure 4 the aforementioned solenoid 20 and die head 21 have effectively been replaced by an electronic head 30 which, under control of the microprocessor 17, is capable of reading or decoding the magnetic stripe on the card 24A and writing on or re-coding that stripe.When the customer requests purchase of the predetermined volume, one pint, of stout, the card 24A which is personal to that customer is inserted into the slot 23A and the head 30 reads the number of pints of the stout that the customer may previously have purchased (from the present or other similar dispensing systems) and which have been accumulated and recorded by the magnetic stripe. This reading is interpreted by the microprocessor 17 and displayed to the customer by an appropriate light emitting device 31 on the facia panel 16.

Following dispensing of a pint of stout through the system as indicated by the timer 17A in the manner previously discussed, the microprocessor 17 signals the head 30 to recode the magnetic stripe to attribute to the record card 24A the purchase of a further pint and this increase in the accumulated number of pints recorded to that customer is indicated by the device 31 on the facia panel.

In the system of Figure 4 the microprocessor 17 is shown with a counter 32 which is preferably obscured from the customer and counts the number of predetermined volumes of beverage that have been dispensed successively through the system. When the counter attains a predetermined number of successive dispensings, say 100 pints of stout, the microprocessor 17 causes a signal to be emitted which may be visual or audible, for example a light emitting device 33 on the facia panel 16 may be actuated to indicate that the predetermined number of dispensings has been attained and the customer at that time may be rewarded as appropriate (for example by having without cost the hundredth pint which was dispensed in addition to the "purchase" of that pint being recorded on the personal log 24A). It will be apparent that the sales promotion facility provided by the counter 32 with an appropriate reward signal such as the device 33 may be applied to the system shown in Figure 2.

The composition, structure and circuitry of the electronic system as discussed herein, such as the comparator 19, microprocessor 17, the timer 17A, the solenoid 20, the electronic head 30 and the counter 32 have not been described in detail as such details will readily be apparent to persons skilled in the relevant art and having an understanding of the present invention.

Claims

1. A liquid flow system comprising a valve which is adjustable to an open or a closed condition to control liquid flow therethrough; control means for determining a predetermined volume of liquid flowing through said valve when in its open condition, and record means responsive to said control means providing an identifiable record automatically in response to flow of said predetermined volume of liquid through the valve.

2. A system as claimed in claim 1 in which the control means comprises a timer actuated when liquid flow through the valve commences and which after a predetermined interval consistent with said predetermined volume of liquid flowing through the valve causes the control means to actuate the record means to provide said identifiable record.

3. A system as claimed in claim 2 in which the timer is sensitive to intermittent flow of liquid through the valve by adjustment of the valve successively between its closed and open conditions and causes actuation of the record means in response to said predetermined volume of liquid flowing through the valve intermittently.

4. A system as claimed in either claim 2 or claim 3 in which override means is provided for said timer which override means determines a maximum period for flow of said predetermined volume through the valve and if said maximum period is exceeded re-sets the timer.

5. A system as claimed in any one of the preceding claims in combination with log means to which said identifiable record is applied automatically in response to said predetermined volume of liquid flowing through the valve.

6. A system as claimed in claim 5 in which the log means provides an indication of a plurality of said predetermined volume of liquid accumulated intermittently and is removably incorporated in the system for use in any one of several similar systems.

7. A system as claimed in either claim 5 or claim 6 in which the record means comprises a stamp or die actuated to mark said log means automatically in response to flow of the predetermined volume of liquid through the valve.

8. A system as claimed in claim 7 in which the stamp or die marks the log means with a security ink having predetermined identifiable characteristics.

9. A system as claimed in either claim 5 or claim 6 in which the log means comprises a magnetic region and the record means comprises an electronic head capable of writing to a memory provided by said magnetic region and said record in response to flow of said predetermined volume of liquid through the valve is applied by the electronic head to the magnetic region.

10. A system as claimed in claim 9 in which the electronic head is capable of reading from the memory of said magnetic region and display means is provided which provides an indication of a number of predetermined volumes of liquid recorded and stored in the memory of the magnetic region.

11. A system as claimed in any one of claims 5 to 10 in which the log means comprises a card.

12. A system as claimed in claim 11 and comprising a slot within which said card is removably accommodated to receive a record in response to flow of said predetermined volume of liquid through the valve.

13. A system as claimed in any one of the preceding claims and comprising liquid sensing means that is responsive to predetermined characteristics of a liquid which is intended to flow through the valve and responds to those characteristics to permit actuation of the record means solely when the predetermined volume of said intended liquid has flowed through the valve.

14. A system as claimed in claim 13 in which the liquid sensing means comprises a light responsive sensor that provides characteristics which vary in accordance with variations in intensity of light applied thereto and a light emitting device that applies light to said sensor through liquid in the system and wherein said sensor provides a response of predetermined characteristics dependent upon the light transmission characteristics of said intended liquid which is to flow through the system and the control means permits actuation of the record means solely in response to the light responsive sensor providing said predetermined characteristics.

15. A system as claimed in claim 14 in which the light responsive sensor comprises a light dependent resistor, the resistance of which varies in accordance with variations in intensity of light applied thereto through liquid in the system and said control means permits actuation of the record means in response to detection of a predetermined resistance of the light dependent resistor consistent with that achieved by the intensity of light applied to the light dependent resistor through the intended liquid.

16. A system as claimed in either claim 14 or claim 15 and comprising a flow responsive member having a first position which it adopts in the absence of liquid flow to the valve to impede light transmission through the liquid from the light emitting device to the sensor and a second position to which flow responsive member is displaced from said first position during flow of liquid to the valve and in which second position light from the light emitting device through the liquid to the light sensor is unimpeded so that the characteristics of the sensor are varied when the flow responsive member is in either its first or its second position and said variation in characteristics provide an indication to the control means whether or not liquid flow has commenced to the valve.

17. A system as claimed in claim 16 in which the control means responds to a variation in the characteristics of the sensor caused by displacement of the flow responsive member from its first position to its second position to provide an output signal indicative that liquid flow to the valve has commenced.

18. A system as claimed in either claim 16 or claim 17 and comprising an upstanding chamber through which liquid flow to the valve is effected upwardly and in which the flow responsive member is located, and wherein the first position of said member is located in a bottom region of the chamber and the second position of the member is located in an upper region of the chamber.

19. A system as claimed in claim 18 in which the flow responsive member is displaced under gravity from its second position to adopt its first position.

20. A system as claimed in any one of claims 16 to 19 in which the flow responsive member is opaque.

21. A system as claimed in any one of the preceding claims and comprising counter means which counts successively each said predetermined volume of liquid that flows through the valve and wherein signalling means is provided that responds to a predetermined number of said successive predetermined volumes of liquid being counted to provide an indication of that attainment.

22. A system as claimed in claim 21 in which following attainment of said predetermined number, the counter means re-sets to commence recounting.

23. A system as claimed in any one of the preceding claims in which the liquid is a beverage and the valve comprises a dispensing tap, and wherein a source of said beverage is provided from which beverage is drawn for dispensing and said drawing is controlled by opening and closing of the tap.

24. A system as claimed in claim 23 in which the dispensing tap is located on a bar unit which comprises said record means and the bar unit has means for removably accommodating a log to which said identifiable record is to be automatically applied in response to a predetermined volume of beverage being dispensed through the tap.

25. A system as. claimed in claim 24 when appendant to claim 21 in which the bar unit has a display panel on which said signalling means displays attainment of said predetermined number.

26. A system as claimed in either claim 24 or claim 25 when appendant to claim 10 in which the bar unit has a display panel on which is indicated the number of said predetermined volumes of beverage stored in the memory of the magnetic region of the log means.

27. A liquid flow system comprising a valve which is adjustable to an open or a closed condition to control liquid flow therethrough; control means for determining a predetermined volume of liquid flowing through said valve when in its open condition; counter means which counts successively each said predetermined volume of liquid that flows through said valve as determined by the control means, and signalling means that responds to a predetermined number of said successive predetermined volumes of liquid being counted to provide an indication of that attainment.

28. A liquid flow sensor comprising a chamber through which liquid is to flow, a light emitting device for applying a light beam through liquid in the chamber to a light sensitive device; a flow responsive member in the chamber that is displaceable between a first position in which it impedes said beam and a second position in which the beam is unimpeded to be applied to the light sensitive device, said member adopting its first position in the absence of liquid flow through the chamber and being displaced to its second position in response to liquid flow through the chamber; said light sensitive device being responsive to variations in light intensity of the beam applied thereto, and wherein control means is provided that responds to predetermined characteristics of the light sensitive device which characteristics indicate liquid flow through the chamber when the member is in its second position and that the liquid in the chamber has predetermined light transmission characteristics.

29. A beverage dispensing system substantially as herein described with reference to Figures l to 3 or Figure 4 of the accompanying illustrative drawings.

30. A liquid flow system as claimed in claim 27 and substantially as herein described.

31. A liquid flow sensor as claimed in claim 28 and substantially as herein described.