GB2193704A

GB2193704A - Control system for beer dispensing

Info

Publication number: GB2193704A
Application number: GB08715467A
Authority: GB
Inventors: Phillip Morgan
Original assignee: PEKTRON Ltd
Current assignee: PEKTRON Ltd
Priority date: 1986-07-02
Filing date: 1987-07-01
Publication date: 1988-02-17
Also published as: DE3780093T2; GB8715467D0; EP0251793B1; DE3780093D1; ATE77803T1; GB8616106D0; EP0251793A1; GB2193704B

Abstract

A beer dispensing arrangement comprises electronic control circuitry (56) having in circuit reed switches (42) and a Hall effect sensor (54), the circuitry (56) also having in circuit a beer pump (24) for moving beer from a supply to dispensing taps (30,32). The reed switches (42) are operated by a magnet in a float (34) while the sensor (54) detects movement of a magnet (52) controlled by a pressure sensitive diaphragm (48). During dispense, with the float (34) being sensed in its uppermost position, the sensor (54) reacts to the pressure in the line and the control circuitry (56) operates by way of the sensor (54) to automatically control the pump (24) and maintain pressure in the line at a desired operating level. Regardless therefore of the condition of either tap (30,32), the arrangement provides a substantially constant rate of dispense.

Description

GB2193704A 1 SPECIFICATION Referring to'Fig. 1 of the drawings, a pump

control unit comprises a body 10 having a Improved liquid dispensing arrangement substantially cylindrical cross section defining a through bore 12 and preferably, formed of a This invention is concerned with improve- 70 moulded plastics material. The body 10 has at ments in or relating to an arrangement for one end thereof a flange 16 by means of dispensing liquid, particularly carbonated be- which an internally threaded securing nut 18 is verages such as beer, under pressure from a retained on the body 10. The latter is ar container, for example to dispense in locations ranged to be connected at said one end by in a bar. 75 means of the nut 18 to a delivery pipe 20 According to the present invention there is from a beer cask or barrel (not shown), an provided an arrangement for dispensing liquid electrically operated pump 24 being opera under pressure from a supply, said arrange- tively connected with the pipe 20. At its other ment, for moving the liquid in a line between end the body 10 has an outlet connection 26 the supply and dispensing means, comprising 80 connected by means of a delivery pipe 28 a pump, pressure sensitive means in the line having two branches to respective dispensing between the pump and the dispensing means taps 30, 32.

and electrical control circuitry including means In the bore 12 there is located a control operable by the pressure sensitive means, the member or a float 34 comprising a magnet circuitry being operable by way of the pres- 85 inserted into a slug preferably of hollow plas sure sensitive means to automatically control tics material and sealed with a close-fitting the pump during dispense so as to maintain plug. The bore 12 is stepped to define a the pressure in the line at a desired operating shoulder 36 which limits movement of the level and thus provide a substantially constant float 34 in an upward direction as viewed in rate of dispense. 90 Fig. 1, when beer is flowing and at the lower Preferably the arrangement includes liquid end of the bore 12 there is provided a retain- flow sensing means in the line between the ing bar 38 to retain the float 34 captive in the pump and the dispensing means, the control bore 12. A housing 40, preferably formed of circuitry including further switch means oper- a plastics material, is positioned with one side able by the liquid flow sensing means, and the 95 adjacent to the body 10. A pair of magnetic circuitry being operable to switch on the pump reed switches 42 are located in the housing in accordance with a reduction in pressure in 40 at said one side to be positioned close to the line from a preset level sensed by the an upper end of the bore 12, such that when pressure sensitive means, and being operable flow of beer in the bore 12 occurs, the float to switch off the pump when there is no 100 34 is moved to an upper postion in the bore liquid flow sensed by the liquid flow sensing 12, as shown by dotted lines, alongside the means and the pressure in the line has reed switches 42. The affect of the magnet reached the preset level. within the float 34 causes the reed switches Preferably also the control circuitry includes 42 to move from a normally open to a closed drive means for the pump whereby control of 105 position, thereby enabling flow to be detected.

the pump can be effected by automatic adjust- A through aperture 44 is provided in a wall ment of the speed of the pump. The pump of the body 10 and is aligned with a through speed may be adjusted by means of phase aperture 46 in the closely adjacent wall of the angle control. housing 40. Between the body 10 and the The operating level at which the pressure in 110 housing 40 a diaphragm 48 is located to the line is maintained may be pre-selected, cover the aligned apertures 44, 46. A spring and may be set by means of a manually ad- loaded pressure button 50 in the housing 40 justable potentiometer included in the control is biassed against the diaphragm 48 such that circuitry. any change in pressure of beer in the bore 12 Further, the control circuitry may be oper- 115 results in a lateral movement of the diaphragm able to switch off the pump after a preset 48 and consequently movement of the pres time delay when there is no liquid flow sensed sure button 50 against the spring bias. The by the liquid flow sensing means and the pressure button 50 has attached thereto a pressure on the line does not reach a preset magnet 52 which is associated with a Hall level, this being indicative of no liquid in the 120 effect sensor 54, the latter being capable of line. detecting any movement in the magnet.52 An embodiment of the present invention will and thus in the pressure button 50 due to the now be described, by way of example only, pressure in the bore 12. The sensor 54 gives with reference to the accompanying drawings a variable voltage and analogue output accord in which: 125 ing to the position of the pressure button 50, Fig. 1 is a schematic view in part section of which is proportional to the pressure within a liquid dispensing arrangement according to the bore 12, whereby the pressure can be the invention; and sensed.

Fig. 2 is a graph showing pressure in the Electronic control circuitry 56 has, in circuit, line during operation. 130 the reed switches 42 and the sensor 54 and 2 GB2193704A 2 is also in circuit with the ele6tric pump 24. A ceases in the bore 12 causing closure of the manually adjustable potentiometer 58 included reed switches 42, if after a preset time per in the circuitry 56 is adjustable from externally iod, for example of 30 seconds, either flow is of the housing 40, and a manual override but- not sensed by the reed switches 42 as a ton 60 is also in circuit with the circuitry 56 70 result of a tap being opened, or the pressure and is accessible from externally of the hous- does not reach the preset level (P) if the beer ing 40. taps are closed, the circuitry 56 operates to When the taps 30, 32 are closed and there switch off the beer pump 24, on the assump- is no flow of beer in the line, the system tion that the beer supply has run out. The pressure is high and is at a level (P) predeter75 manual override button 60 enables this delay mined by the control circuitry 56 (see Fig. 2). period to be restarted when attaching a new This level (P) can be factory set and can be barrel or installing the equipment.

nominally set at 50 PSI. When the tap 30 is There is therefore provided an arrangement opened the system pressure falls below the wherein, during dispense, the flow rate can be At level (P) and this fall is detected by the pres- 80 automatically maintained substantially constant, sure sensor 54 due to movement of the dia- even if a plurality of beer taps fed from a phragm 48 and the pressure button 50. While single electric pump had opened simultane there is no flow in the line the control circuitry ously. Installation and set up are very simple 56 causes the beer pump 24 to run at full and the arrangement has only one control speed. The flow which is subsequently 85 which requires adjustment by the user, i.e. the created in the bore 12 raises the float 34 pressure setting potentiometer to determine alongside the reed switches 42. The closure the dispense pressure and therefore the speed of the latter causes the control circuitry to of dispense. In between dispenses the line adjust the speed of the beer pump 24 by pressure is maintained at a relatively high pre means of phase angle control until the pres- 90 set level to help stop breakout of carbon diox- --sure detected within the bore 12 corresponds ide in very gassy beers. The switching off of to an operating pressure setting C selected by the beer pump after the time delay in the the user by way of the pressure setting po- event that the beer supply runs out prevents tentiometer 58. The control circuitry 56 there- excessive pump wear due to dry running.

fore switches to a constant pressure mode, 95 It will be appreciated that the closed loop the system pressure selected by the user de- system can be used in any beverage dispense termining the speed of dispense at the bar tap installation so to automatically maintain line - 30. pressure and thus flow rate at a substantially If the tap 32 is then also opened, the sysconstant value during dispense.

tem pressure will fall again. The control cir- 100 Various modifications may be made without cuitry 56 is then arranged to automatically addeparting from the invention. For example just the speed of the beer pump 24 until the control of the pump may be by other than pressure within the bore 12 once again corre- speed control, and the configuration of certain sponds to the setting C on the potentiometer of the components may differ from that de 58. In this way the circuitry 56 by means of a 105 scribed and shown, provided the components closed loop feedback system varies the speed function in the required manner.

of the beer pump 24 so as to maintain con

Claims

stant pressure in the line, despite anything CLAIMS which may occur so as

to otherwise affect 1. An arrangement for dispensing liquid un- the system pressure during dispense. Similarly, 110 der pressure from a supply, said arrangement, -when the tap 32 is closed again with the tap for moving the liquid in a line between the still open, the circuitry 56 will operate to supply and dispensing means, comprising a maintain the pressure within the system con- pump, pressure sensitive means in the line be stant at setting C. tween the pump and the dispensing means When both taps 30, 32 are closed the flow 115 and electrical control circuitry including means of beer in the line will cease. The fall of the operable by the pressure sensitive means, the float 34 will close the reed switches 42 to circuitry being operable by way of the pres enable the control circuitry 56 to detect that sure sensitive means to automatically control flow has ceased. The circuitry 56 is arranged the pump during dispense so as to maintain to then cause the beer pump 24 to run again 120 the pressure in the line at a desired operating at full speed, thus causing the system pres- level and thus provide a substantially constant sure to rise rapidly until the pressure reaches rate of dispense.

the relatively high preset value (P). When the
2. An arrangement according to Claim 1, level (P) is reached the sensor 54, together including liquid flow sensing means in the line with the closure of the reed switches 42, 125 between the pump and the dispensing means, causes the circuitry 56 to switch off the beer the control circuitry including switch means of pump 24. The beer line is then again ready the liquid flow sensing means, and the circuitr for further dispense. being operable to switch on the pump in ac- - When the circuitry 56 causes the beer cordance with a reduction in pressure in the pump 24 to run at full speed, i.e. if flow 130 line from a preset level sensed by the pres- 3 GB2193704A 3 sure sensitive means, and being operable to switch off the pump when there is no liquid flow sensed by the liquid flow sensing means and the pressure in the line has reached the preset level.
3. An arrangement according to claim 2, wherein the control circuitry is operable to switch off the pump after a preset time delay when there is no liquid flow sensed by the liquid flow sensing means and the pressure in the line does not reach a preset level, this being indicative of no liquid in the line.
4. An arrangement according to any of claims 1 to 3, wherein the control circuitry includes drive means for the pump whereby control of the pump can be effected by auto matic adjustment of the speed of the pump.
5. An arrangement according to claim 4, wherein the pump speed is adjusted by means of phase angle control.
6. An arrangement according to any of the preceding claims, including means for pre-se lecting the operating level at whichthe pres sure in the line is maintained.
7. An arrangement according to claim 6, wherein the pre-selection means comprises a manually adjustable potentiometer included in the control circuitry.
8. An arrangement according to any of the preceding claims, wherein the pressure sensi tive means comprises a member carrying a magnet and the means associated with the pressure sensitive means comprises a sensor in the control circuitry for detecting movement of the magnet.
9. An arrangement for dispensing liquid un- der pressure for a supply substantially as hereinbefore described with reference to the accompanying drawings.
10. Any novel subject matter or combina- tion including novel subject matter herein dis closed in the foregoing Specification or Claims and/or shown in the drawings, whether or not within the scope of or relating to the same invention as any of the preceding claims.

Published 1988 at The Patent Office, State House, 66/71 High Holborn, London WC 1 R 4TP. Further copies may be obtained from The Patent office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD.

Printed by Burgess & Son (Abingdon) Ltd. Con. 1/87.