GB2033343A

GB2033343A - Dispensing of beverages

Info

Publication number: GB2033343A
Application number: GB7934926A
Authority: GB
Original assignee: Porter Chadburn Ltd
Current assignee: Porter Chadburn Ltd
Priority date: 1978-10-10
Filing date: 1979-10-09
Publication date: 1980-05-21
Also published as: GB2033343B

Abstract

A beverage dispenser, for dispensing predetermined measured quantities of beverage only after the complete filling of a measuring device (11), comprises a holding device (52) between the measuring device (11) and the dispense point, to temporarily receive beverage discharged from the measuring device (11), the capacity of the holding device (52) being variable according to the discharging beverage pressure relative to a datum pressure which purges the holding device (52) of beverage on cessation of the discharge. The holding device (52) comprises two regions created by a piston in a cylinder or a diaphragm (56) across a chamber, the volume of the holding device (52) being determined by the piston position or diaphragm (56) configuration. One region is subjected to the datum pressure and the other region to the discharging beverage pressure, the piston or diaphragm (56) being movable by such pressures. The measuring device (11) may comprise a chamber having a diaphragm (14) therein movable by beverage as it fills the measuring device (11) and movable in the opposite direction by pressure air at the datum or a greater pressure. <IMAGE>

Description

SPECIFICATION Dispensing of beverages The invention concerns the dispensing of beverages, particularly, though not exclusively carbonated beverages, and has more particular reference to the dispensing of immediately successive multiples of a predetermined measured quantity.

It is now common practice to dispense beer by delivering predetermined measured quantities, say half pints, to a dispense tap, the arrangement being such that the dispense system cannot be reactivated to deliver a further quantity until completion of the delivery cycle of the first quantity, thereby avoiding the serving of short measure.

The usual practice, when it is required to deliver multiples of the measured quantity, say two half pints, into the same glass, is for the bar staff to keep depressed the switch controlling operation of the measuring device throughout the delivery of the first measure, the second delivery cycle thus being initiated immediately upon the completion of the previous cycle, or for such staff to release the switch after initiation of the first cycle and again to operate the same upon completion of such cycle. In either event the flow of beer through the tap must necessarily be interrupted whilst the measuring device is recharged from the bulk supply in the cellar. This delay is inconvenient both to the customer and the bar staff, and especially to the latter during particularly busy periods.

The object of the invention is to reduce or eliminate the delay whilst still ensuring that a full measured quantity is delivered for each dispense cycle.

According to the invention there is proposed a beverage dispenser for dispensing a predetermined measured quantity at each cycle of operation comprising a measuring device to which beverage is delivered from a bulk supply thereof and from which said beverage is discharged to a dispense point, the arrangement being such that discharge cannot be effected until delivery is completed in full, characterised by a holding device of variable capacity intermediate the measuring device and dispense point adapted temporarily to receive beverage from the said measuring device during passage to the dispense point, the capacity of the holding device being automatically variable according to the pressure of the beverage discharged by the measuring device in relation to a datum pressure so selected that on cessation of such discharge the said datum pressure operates to purge the holding device of beverage.

Preferably, the holding device includes a piston slidably supported in a cylinder, the opposite sides of the said piston being subjected to the said datum pressure and the pressure of the beverage flowing to the dispense point, respectively, and the volume of the device being determined by the position of the piston axially of the cylinder.

According to a further preferred feature, the effective surface area of the piston subjected to the datum pressure is less than the surface area of the piston subjected to beverage pressure.

According to a still further preferred feature, the measuring device includes a diaphragm movable in a first direction by beverage under pressure applied to one face thereof on filling of the device and movable in the opposite direction by pressure air applied to the other face thus to effect discharge of the device, there being selectively operable uni-directional valves controlling passage of beverage to and from the device, the datum pressure as applied to the holding device corresponding to the air pressure as applied to the diaphragm on discharge of the measuring device.

According to a still further preferred feature, the dispenser includes a flow-controlled dispense tap, such as disclosed, in prior United Kingdom Patent Specification No. 1,260,842.

The invention will now be described further, by way of example only, with reference to the accompanying drawings illustrating alternative embodiments thereof, and in which: Fig. 1 is a diagrammatic side elevation, partly in cross-section, of a part of a dispense system embodying the invention; Fig. 2 shows a part of the arrangement of Fig. 1 in cross-section and to a larger scale; Fig. 3 is a longitudinal section through the holding device of the present invention, again drawn to a larger scale; Fig. 4 is a view simiiar to Fig. 1 of an alternative embodiment of dispense system; Fig. 5 is a longitudinal section through the holding device of Fig. 4; and Fig. 6 is a longitudinal section through a differential pressure regulator for use with the embodiment of Figs. 4 and 5.

Referring now to the drawings, and particularly to Fig. 1 thereof, a beer dispense system includes a measuring device 11 to which beer is delivered from a bulk supply thereof (not shown), and from which beer is discharged to a dispense tap (not shown), and a holding device 12 intermediate the measuring device and dispense tap.The measuring device 11 comprises two flanged, dished body parts 13, 1 3a arranged in face-toface relationship and supporting a diaphragm 14 therebetween, one side of the diaphragm receiving beer from the said supply via a beer inlet 15, (Fig. 2) and the other side of the diaphragm being subjected to pressure air from a suitable source 1 6. A common inlel/outlet 1 7 is provided in the body part for the passage of beer to or from the space 1 8 at the one side of the diaphragm 14, there being a spring-loaded, pneumatically actuated valve 1 9 for controlling passage of beer to or from such space.The construction of valve 1 9 is shown in detail in Fig. 2, and such valve will be seen to comprise an axially shiftable valve member 20 selectively engageable with outlet valve seating 22 under the combined effects of valve 1 9 and compression springs 23, 29, and a non-return valve 21 supported relative to valve member 20 and resiliently connected thereto via compression spring 23. Valve member 20 is in abutment with one end of a valve stem 24 slidable in a valve block 25, the other end of the said stem 24 carrying a piston 26 movable in a cylindrical chamber 28 in the valve block and adapted to be subjected to pressure air via a further diaphragm 27.Spring 29 which spring 29 is substantially stronger than spring 23, is provided between the piston 26 and valve block 25 and serves primarily to return the piston to an initial position and allow engagement of valve member 20 with seating 22 in the absence of pressure air on diaphragm 27.

Upon application of pressure air to diaphragm 27 via a solenoid valve, not shown, the valve stem 24 is shifted to the left, as seen in the drawing, against the resistance of the springs 23, 29 to move valve member 20 from its sealing engagement with seating 22, in which position the space 1 8 is automatically in fluid flow communication with the beer supply through nonreturm valve 21, to a position wherein the valve member closes the non-return valve 21 thus closing the beer inlet 15, space 18 then being in fluid flow communication with the dispense tap.

Conveniently, that body part 1 3 which, together with the diaphragm 14, defines the beer receiving space 18, has an inner surface defined by a stainless steel liner 30, the liner providing a high degree of corrosion resistance and avoiding the need for the application of an expensive epoxy resin coating to the beer contacting suface of the body part.

The holding device 12, see now Fig. 3, comprises two spaced end caps 31,32 formed by a cylindrical sleeve 33 supported on inwardly facing, axially directed flanges 34, 35 of the said end caps. A piston 36 is freely slidable within the sleeve between the limits as defined by the end caps, 31,32 the said piston 36 having a respective radially outwardly directed flange 37 at each end thereof which is clearance in the sleeve and which carries a respective sealing ring 38 thus to support the piston 36 in sealed relationship with the sleeve 33. The annular space 39 between the flanges 37 is vented to atmosphere through an aperture 40 in the sleeve, the arrangement being such that the aperture is in register with the said annular space throughout the full range of movement of the piston.

A blind axial bore 41 is formed in that face of the piston adjacent end cap 31, such bore 41 receiving the enlarged inner end 42 of a tube 43 as a clearance fit therein, there being a sealing ring 44 on such enlarged end for sealing engagement with the cylindrical surface of bore 41, the tube 43 being mounted in end cap 31 and blind bore 41 being connected to atmosphere via tube 43.

An inlet 45 is also provided in end cap 31 to allow of the application of air under pressure to the end face of piston 36.

End cap 32 has a diametrically directed through passage 46, and an axial blind bore 47 of substantially greater transverse dimension than passage 46, there being a non-return valve 48 engageable with a seating 50 in passage 46 under the control of a return spring 51, passage 46 being connected with the common inletloutlet 1 7 via outlet valve seating 22 to receive beer from the measuring device.

In use, line air pressure is introduced into t le holding device via air inlet 45, and is thus applied to that end face of the piston adjacent end cap 31.

On initiation of a dispense cycle pneumatic valve 19 is operated to move valve member 20 to a position to connect space 18 in fluid flow relationship with the dispense tap and isolate such space from the beer supply.

Simultaneously, air under pressure is applied to the air side of diaphgram 14, thus to displace the same and discharge beer from the measuring device. Having regard to the differential nature of piston 36, the beer flowing to the holding device, and thence to the dispense tap, will displace piston 36 against the restraint of the pressure air applied to the opposite face thereof, and will thus create a space to receive some of the beer discharged from the said device, flow through the tap continuing during axial displacement of the piston.On completion of discharge of beer from the measuring device, the pressure of the beer flowing through the holding device will fali, and thus the air pressure as applied to the air side of the piston will cause such piston to move against the resistance of pressure derived from the beer, and will purge the space in the holding device of beer and thus complete the dispense operation, the tap conveniently being of the flow-controlled type disclosed in British Patent Specification No.

1,260,842 and thus remaining open whilst beer continues to flow.

Immediately upon the completion of its discharge cycle the solenoid valve controlling valve 19 and the application of pressure air to the air side of diaphragm 14 operate to allow the return of valve member 20 to its position of engagement with seating 22, whereupon space 18 starts to fill with beer.

On completion of the filling of space 18, a further actuation of the solenoid valve to shift valve member 20 and to apply air to the underside of diaphragm 14 will again discharge beer towards the dispense tap. If the purging of beer from the holding device has been completed, then the procedure of piston displacement against the restraint of the pressure air applied to the air face thereof and the subsequent return motion of the piston will be repeated, whereas if purging is incomplete, then the motion of the piston will be reversed.

It will be seen, therefore, that with a sufficiently fast refilling of the measuring device a continuous flow of beer at the tap for two operations of the measuring device is possible, with consequential saving in time. Even if the refilling of the measuring device is not sufficiently fast for refilling to be completed before completion of the purging of the holding device, there is still a saving in time in that the measuring device is able more quickly to discharge its contents than would be the case if the holding device were not present in view of the reduced rate of flow from the measuring device due to the dimensions of the tubing connecting the device with the dispense point.

- ie invention, whilst being of particular application in the context of measuring devices of the kind here disclosed, is not iimited to such measuring devices and may be used in conjunction with other conventional such devices.

Furthermore, the holding device need not be of the exact form of that disclosed, since alternative structures will readily present themselves to one skilled in the art. For example, as an alternative to providing restraint to movement of the piston by way of air under pressure, it may be preferred to provide a resilient means to provide restraint.

An alternative embodiment of dispense system is shown in Figs. 4 and 5. In this embodiment the measuring device 11 and valve 1 9 are as described above in relation to the embodiment of Fig. 1 but the holding device 12 of that embodiment is replaced by an alternative holding device 52. This alternative holding device 52 comprises a dished housing 53 having a close fitting stainless steel liner 54 and being bolted to a back plate 55. Sealed between the housing 53 and back plate 55 is a diaphragm 56 and there is a beer inlet/outlet part 57 located in the housing 53 and communicating with the space to one side of the diaphragm 56. An air inlet 58 is located in the back plate 55 to provide for pressurisation of the space on the other side of the diaphragm 56.The inlet/outlet part 57 is connected to the flow line from the valve 19 9 by the tee-piece 59 which houses a non-return valve 60 in its inlet branch, the valve seating 62 being biassed towards the no-flow condition by means of a light spring 61.

Figure 6 illustrates an arrangement of pressure regulators suitable for use with the embodiment of Figs. 4 and 5. The arrangement comprises a main regulator 1 6 located in a supply line from a source of compressed air to the measuring device or dispenser 11, and in this respect the two embodiments of the invention herein described are the same. However in the embodiment of Figs. 4 and 5 a further feed line 63 connects the downstream side of the main regulator 1 6 to the holding device 1 2. Located in the feed line 63 is a differential regulator 69 which provides that the air pressure in feed line 63 is always a fixed proportion of that at the downstream side of the main regulator 1 6, for example 70% to 80% thereof.The differential regulator 64 comprises upper, lower and intermediate chambers 64, 65 and 66 respectively, the latter being open to atmosphere at 68. Diaphragms 67, 70 having different surface areas are located between the intermediate chamber 66 and respectively the upper chamber 64 and the lower chamber 65, on the inlet side of the latter there being valve 71 on push rod 73 and resilientiy biassed towards the closed position by spring 72. Push rod 73 is moved by diaphragm 70 to open valve 71. Should the reduced pressure in chamber 65 increase above the desired level the diaphragm 70 will move upwardly to open vent passage 75 which communicates with the intermediate chamber 66 and atmosphere.

The manner of operation of the embodiment of Figs. 4 to 6 is similar to that of the previously described embodiment, beer being admitted to the holding device 12 as it is dispensed from the measuring device 11, and then being expelled therefrom when the measuring device 11 is empty and the air pressure on the diaphragm 56 exceeds the pressure thereon due to the beer in the holding device 12.

The form of differential regulator 69 described herein is for example only, since many other forms of such device are known and may be used in the present context.

Claims

1. A Beverage dispenser, for dispensing a predetermined measured quantity at each cyle of operation comprising a measuring device to which beverage is delivered from a bulk supply thereof and from which said beverage is discharged to a dispense point, the arrangement being such that discharge cannot be effected until delivery is completed in full, characterised by a holding device of variable capacity intermediate the measuring device and the dispense point and adapted temporarily to receive beverage from said measuring device during passage to the dispense point, the capacity of the holding device being automatically variable according to the pressure of the beverage discharged by the measuring device relative to a datum pressure so selected that on cessation of such discharge the said datum pressure causes purging of the holding device of beverage.

2. A beverage dispenser according to claim 1 wherein said holding device comprises a piston slidably supported in a cylinder and providing two regions in said cylinder on opposed sides of said piston, the volume of said holding device being determined by the position of said piston in said cylinder.

3. A beverage dispenser according to claim 1 wherein said holding device comprises a chamber which is divided into two regions by a diaphragm extending across said chamber between said regions, the volume of said holding device being determined by the configuration of said diaphragm within said chamber.

4. A beverage dispenser according to claim 2 or claim 3 wherein one of said two regions is subject to pressure of beverage passing from said measuring device to said dispense point.

5. A beverage dispenser according to claim 4 wherein the other one of said two regions is subject to said datum pressure.

6. A beverage dispenser according to claim 5 when dependant upon claim 2 wherein the effective surface area of said piston subjected to the datum pressure is less than the effective surface area of said piston subjected to the pressure of said beverage.

7. A beverage dispenser according to any preceding claim wherein said measuring device comprises a chamber having a diaphragm therein and extending thereacross.

8. A beverage dispenser according to claim 7 wherein said diaphragm is movable in a first direction by beverage under pressure applied to a first face thereof on filling of said measuring device.

9. A beverage dispenser according to claim 8 wherein said diaphragm is movable in a second direction opposed to said first direction by pressure air applied to the second face opposed to said first face.

1 0. A beverage dispenser according to claim 9 wherein said pressure air is at said datum pressure.

11. A beverage dispenser according to claim 9 wherein said pressure air is at a pressure greater than said datum pressure by a predetermined amount.

12. A beverage dispenser according to claim 11 wherein said measuring device is in connection with a supply of pressure air and a differential pressure regulator is provided between said air supply and said holding device.

1 3. A beverage dispenser according to any one of claims 7 to 10 comprising selectively operabie uni-directional valves adapted to control passage of beverage to and from said measuring device.

14. A beverage dispenser according to any one of the preceding claims further comprising a flow controlled dispense tap.

1 5. A beverage dispenser substantially as hereinbefore described with reference to and as illustrated in Figs. 1 to 3 or Figs. 2 and 4 to 6 of the accompanying drawings.