GB2221209A - Liquid monitoring system for beer dispenser - Google Patents

Abstract

A liquid monitoring system for beer or the like has monitoring means 12 connected in each beer pipe line 14 adjacent to the dispenser 18. The monitoring means comprises a flow measuring device and a beer sensor which disables the effect of the flow measuring device when a liquid other than beer flows through the pipe. The sensor discriminates between beer and other liquids by sensing the pH of the liquid and/or its colour. The monitoring means are connected in the beer line by means of heat-sealable sleeving 15. The flow measuring device is of the type which delivers a train of pulses each of which represents the same volume of beer, and feeding a circuit comprising a programmable counter acting as a divider and feeding an accumulator counter. The system has a plurality of beer lines each with monitoring means feeding a central unit to, which includes means for detecting and indicating (23) tampering with the unit and/or the connections to it, and a back-up battery and a mains interruption detector and indicator (23). <IMAGE>

Description

Liquid Mor? it or ig System The present invention relates to liquid monitoring systems, and more particularly to systems for stock control of beer and the like which is sold at.

licenced premises via dispenser taps at a bar.

In licenced premises, there is a need for stock control; that is, means which enable the quantities of the various free-flow beers (keg and cask beers) used to be measured. This is particularly important in public houses operated by managers and in clubs, because the beers are under the management of a manager who is not the owner, and who is therefore in a position to misrepresent the sals to the true owners.

Various means of stock control are already available. The quantity of beer delivered to the premises is, of course, usually known, but the quantities sold are not so easily measured. The casks and kegs can be weighed or dipped, but this is inconvenient, and it is difficult to equate the results with the takings without going through the procedure daily. Further, there is no control over alleged wastage, or even watering of the beer.

A dispense recorder has been proposed which is connected in the beer line to a beer tap, and which measures the quantity of beer flowing through it.

However, although this unit has good internal security, the security of the system as a whole is severely compromised because various means of attack are available which do not require tampering with the unit itself.

The object of the present invention is to provide a beer stock control system which is inexpensive and has high security.

According to the invention a liquid monitoring system for beer or the like comprises monitoring means, connected in a pipe line feeding a dispenser, comprising a flow measuring device and a beer sensor operative to disable the effect of the flow measuring device when a liquid other than beer flows through the pipe. The "liquid other than beer" will usually be water or a cleaning liquid, which are used to flush'oust and clean the line at suitable intervals. The sensor may discriminate between beer and other liquids by utilizing any conveni ent characteristic (or combination of characteristics) by which beer differs from the other liquids likely to be used, such as pH or colour.

By this means, the manager of the premises is not required to turn the monitoring system off for cleaning and back on after cleaning, or to change any connections. On the contrary, the system preferably includes means for proofing it against tampering, so that the connections cannot be changed.

The flow measuring device and the beer sensor are preferably connected adjacent to each other and close to the dispenser.

The flow measuring device may conveniently be of the type which delivers a train of pulses each of which represents the same volume of beer. The circuit which receives and counts these pulses preferably comprises a programmable counter acting as a divider and feeding an accumulator counter. This permits the count of the accumulator to represent accurately the volume of beer, the value of the divide constant of the programmable counter being adjusted to compensate for any variation from nominal of the pulse/volume ratio of the sensor.

The system preferably comprises a plurality of flow measuring devices and sensors, one of each for each of a plurality of beer lines, feeding a single central control unit. The control unit preferably includes various means for proofing it against tampering.

Further significant features of the invention, and various modifications and developments thereof, will become apparent from the following description of a beer management system in accordance with the invention, given by way of example and with reference to the drawing, which is a block diagram of the system.

The general. system consists of a plurality of monitoring devices connected il, beer lines and coupled to a control box. Each monitoring device includes a flow sensor and a chemo-sensor which can distinguish between beer and cleaning liquid. The monitoring device connections are covered by heat-shrink sleeves with internal heat-set table adhesive; such sleeves may also be used for other connections in the beer lines. The control box is mains powered with an internal battery back-up, and a non-resettable mains failure indicator which operates if the mains power is disconnected for more than a predetermined time.

The control box has a non-resettable tamper indicator which operates if its lid is opened. Each sensor channel has an associated counter for counting the pulses from its associated sensor to measure the beer flow, and means for monitoring a break in the connection to the monitoring device and on a break setting a non-resettable indicator. All "non-resettable" indicators are reset table only by an operator with a key.

Referring to the drawing, a control unit 10 has four cables 11 emerging from it, connected to respective monitoring devices 12, and a mains cable 16.

Various meters and indicators are provided on the face of the box 10, together with a key-operated switch 17.

Each monitoring device consists of a unit having a through path for beer between two pipe connections 13, and is connected in a beer line 14. The two components of the monitoring device, the flowmeter and the beer sensor, may be separate, but are preferably included in a single unit a shown.

The output side of the monitoring device is preferably connected directly to the input of a dispenser 18, so that there is no intermediate portion of beer line into which an illicit further connection could be r. ie to bypass the d-tect.jz. The junctions between the pipe connections 13 and the end of the beer line 14 and the dispenser 18 are protected by means of sleeves 15. These sleeves are made of heat shrinkable plastics material, and ere coated inside with heat set stable adhesive. They are put onto the end of the beer line 14 and the inlet to the dispenser 18, the beer line and dispenser inlet are joined to the connections 13, and the sleeves are then slid over the joins and heated to shrink and fix them into place. This results in a high security for the connections of the monitoring device 12; that is, it is extremely difficult for the connections to be broken and remade without the break being evident.

The sleeves may be formed with distinctive patterns of colours and/or corrugations to increase the security of the fixings even further. Similar sleeves may be used for any other connections in the beer line, making it equally difficult for a long by-pass round the monitoring device to be installed.

The system is designed to be permanently connected and continuously operative, even during beer line cleaning operations. This increases its security greatly compared to systems in which either the flowmeter has to be disconnect able for cleaning operations or allowance has to be made for the passage of cleaning liquid through the flowmeter. (Of course, the upstream end, where the beer line is connected to the beer cask or keg, has to be free so that the casks and kegs can be changed.) Each monitoring device 12 contains two sensors, a flow sensor and a chemosensor.The flow sensor is of known type, consisting of a paddle wheel which r-otates as liquid flows through the device, an LED, and a photosensor which detects the interruptions of the beam from the LED as the paddles of the paddle wheel pass across the beam. (The pulse rate is typically in the region of 1000 pulses per litre.) The chemosensor continuously monitors the nature of the liquid passing through the device, discriminating between beer and cleaning liquid.

The chemosensor consists essentially of a pH monitoring device. We have found that the pH of beers is normally less than 5 (i.e. somewhat acid), even for low-alcohol and alcohol-free beers, whereas the pH of water is higher than this, typically around 8 (i.e. slightly alkaline), and that of cleaning liquids of well above that of water. Hence by setting the discrimination level at a pH of about 5.5, reliable discrimination between beer and cleaning liquids can be achieved.

The discrimination level can be set to discriminate between pure beer and wotered beer, but this setting will usually depend on the particular beer and water involved, and would have to be very delicate to detect only slight watering. However, there is no advantage to the manager in diluting.the beer, because the system measures the total quantity sold, whether or not it has been diluted.

It will be realized that other or further sensors able to discriminate between beer and other liquids can also be used. For example, a colour sensor can be used, since beers have a distinctive yellow or brown colour compared to water and typical cleaning liquids. Different types of sensors will of course generally have different sensitivities and response times.

The discrimination between beer and cleaning fluid may be aided by choosing a cleaning fluid which has some characteristic markedly different from beer.

Thus it may be made deliberately alkaline to enhance its contrast with beer, it may have a colouring agent included in it which gives a contrast with brown or yellow (e.g. blue), or it may have an agent included in it which fluoresces under ultraviolet light. The sensor, or some component thereof, will be designed to take advantage of the relevant characteristic, e.g. by including an ultraviolet source and a photosensor sensitive to the fluorescence wavelength in the case last mentioned.

The use of specially formulated cleaning fluid, if such is chosen, does not reduce the security of the system. There is no advantage to the manager in not using the correct cleaning fluid, because if he should substitute a different cleaning fluid which is not detected as such by the sensors, it will register as beer and so increase the apparent quantity of beer sold relative to the true quantity.

The lengths of the cables between the box 10 and the devices 11 will vary widely, depending on the geography of the premises in which the system is installed. The system may incorporate various means for attaining high security for these cables. One method is for the device end of a cable to be permanently incorporated in the monitor body, and the box end of the cable to be connected internally in the box, so that that connection cannot be tampered with without opening the box. (The security of the box will be discussed later.) Another is for the end connections of the cable, and any junctions in it, to be protected by sleeves similar to the sleeves 15.

Another technique is for the box 10 to carry out active monitoring of the cables 11 to check that they are connected to the devices 12. This may consist for example simply of checking that a continuous connection is maintained between two lines of the cable 11 and the device 12, or a more elaborate system may be employed wherein an interrogation signal is sent from box 10 to device 12 and device 12 sends back a response signal. This may be further elaborated by providing each device 12 with a different interrogation and/or response signal, to prevent two devices 12 from being interchanged.

Of course, several of these security techniques may be employed in combination.

The control box 10 is made of or coated with plastics material, to withstand use in typical beer cellar environments. As notea, it hos a key-operated switch 17, which can be switched to various states. Such states include OFF and ON; in addition, RESET and TEST states may be provided. The OFF and ON states are self-explanatory; the RESET state is used. to reset any indicators which have operated, and the TEST state is used to test the indicators. The box may be of sealed construction so that it can only be opened by the key. Alternatively, it may have removable panels, in which case it preferably has tamper-detecting microswitches beneath such panels, coupled to a non-resettable indicator, so that the system security is maintained.

The mains connection 16 of the box 10 may be made secure in the same way as the connections of the cables 11. However, this is not always feasible, and brief interruptions of the mains supply may nevertheless occur. The box 10 therefore contains a transformer and rectifier for operating the electronic circuitry, and also contains a back-up battery, rechargeable from the mains, to keep the box operating in the event of a mains interruption. A mains interruption detector may be provided, preferably including a delay, feeding a nonresettable indicator, so that any. prolonged period of disconnection from the mains is indicated.

The case also contains four counters 20 for the four monitoring devices 12.

Each counter is a mechanical non-resettable counter driven by the pulses from the associated device 12, via a calibrating divider which is set to match the particular characteristics of the associated device 12 and a unit divider which is set to measure, e.g. half-pints, pints, or litres. The dividers are accessible only from within the box 10. The mechanical counters may be reset table from within the box, or they may be true non-resettable counters.

Each counter has a label holder 21 above it, to contain the name of the particular beer which it monitors. Each also has an indicator light 22 below it, which is. lit if the circuitry detects any tampering with or disconnection of the associated device 12. A further set of indicator lights 23 is provided to indicate mains on, mains failure, tampering with the box 10, etc.

The monitoring devices 12 may include only flow sensors, not chemo-sensors as well, and one key position may be CLEAN, in which the operation of the counters 20 is disabled. The security of this system.is however self-evidently reduced by this modification. Its security can be increased to some extent by providing a time control' for the CLEAN state, consisting of a non-reset table clock circuit which permits the CLEAN state to be entered only during hours when the premises are closed. Further, a recorder (e.g. a printer and paper tape) can be provided inside the box 10 which operates when the switch 17 is set to CLEAN to record, for example, the start and finish times of the CLEAN state, the flows through the various devices 12 in that state, and the times of those flows.

This will make it difficult for a dishonest manager to draw beer during the CLEAN state, since the pattern of flows for that will be different from the pattern for genuine cleaning.

In some cases, the established pattern of cleaning is that a beer line is cleaned when a new cask or keg is being attached to it. This will usually occur during a period when beers are being served, so the time control technique just discussed cannot be applied. Some degree of security can however be attained by the recording technique just discussed, since the flow pattern of normal cleaning should be fairly consistent.

The circuitry in the box 10 may use conventional multiplexing techniques for controlling and sensing the states of the devices 12 and driving the coulters 20.

The system may be expanded by the addition of one or more expansion boxes 25. Each expansion box has four cables for connection to four monitoring devices, and four counters for counting the flow through those devices. However, the expansion boxes share the power supply circuitry and other electronic circuitry of the main box 11. The expansion boxes stack on top of the box 10, and are attached to the stack by key-operated locks.

In a modified and more elaborate form of the system, a microprocessor is used. For this, the box 10 is provided with a keyboard on its face, to enable a variety of functions to be obtained with the aid of the microprocessor. The four mechanical counters are replaced by four locations in an internal RAM memory, and a single liquid crystal display. The state of any of the monitored beer lines can be displayed in detail, e.g. showing the line number, price, total pints, session pints, session value, and last reset, as selected by means of the keyboard. With this system, any reasonable number of lines can be monitored by a single box.

This system can be provided with interface means for linking it to an EPOS (electronic point of sale) system, a management system, and/or a printer.

In this system, it may be desirable for various parameters to be modifiable by means of the keyboard, e.g. the prices of the beers. To minimize the security risks which such modifiability invoives, the system may include an internal archive memory which records all parameter changes and the conditions (time, totals pints for each beer, etc) at each parameter change.

Claims (14)

C la im s

1 A liquid monitoring system for beer or the like including monitoring means, connected in a pipe line feeding a dispenser, comprising a flow measuring device and a beer sensor operative to disable the effect of the flow measuring device when a liquid other than beer flows through the pipe.

2 A liquid monitoring system according to claim 1 wherein the sensor discriminates between beer and other liquids by sensing the pH of the liquid.

3 A liquid monitoring system according to either previous claim wherein the senaor discriminates between beer and other liquids by sensing the colour of the liquid.

4 A liquid monitoring system according to any previous claim wherein the monitoring means is connected in the beer line by means of heat-sealable sleeving.

5 A liquid monitoring system according to any previous claim wherein the monitoring means is connected in the beer line adjacent to the dispenser.

6 A liquid monitoring system comprising a plurality of beer lines each of which includes a monitoring means according to any previous claim, and a central unit fed by all monitoring means.

7 A liquid monitoring system according to claim 6 wherein each flow measuring device is of the type which delivers a train of pulses each cf which represents the same volume of beer.

8 A liquid monitoring system according to claim 7 wherein each flow measuring device feeds a respective circuit in the central unit comprising a programmable counter acting as a divider and feeding an accumulator counter.

9 A liquid monitoring system according to any one of claims 6 to 8 wherein the central unit includes means for detecting and indicating tampering with the unit and/or the connections to it.

10 A liquid monitoring system according to any one of claims 6 to 9 wherein the central unit contains a back-up battery and a mains interruption detector and indicator.

11 A liquid monitoring system according to any one of claims 6 to 10 wherein the central unit can be set to a CLEAN state in which the disabling of the effect of the flow measuring device by the beer sensor when a liquid other than beer flows through the pipe is inhibited.

12 A liquid monitoring system according to claim 11 wherein the central unit includes time setting means which permit the CLEAN state to be entered only at predetermined times.

13- A liquid monitoring system according to either of claims 11 and 12 wherein the central unit includes means for recording the flow pattern while the central unit is in the CLEAN state.

14 A liquid monitoring system substantially as herein described.