GB2281283A

GB2281283A - Beverage dispensing pump with cooling means.

Info

Publication number: GB2281283A
Application number: GB9317675A
Authority: GB
Inventors: Geoffrey Ian Bell; John Robert Charles Paul Maggs; Brian Mullen; Shaun White
Original assignee: HOMARK GROUP Ltd
Current assignee: HOMARK GROUP Ltd
Priority date: 1993-08-25
Filing date: 1993-08-25
Publication date: 1995-03-01
Anticipated expiration: 2013-08-25
Also published as: GB2281283B; GB9317675D0

Abstract

A beer dispensing pump 1 in the form of a beer engine comprises a dispensing piston 2 movable within a cylinder 3. The upper end of the cylinder 3 incorporates an external jacket 4 within which heat transfer fluid (chilled water) is circulated. The pump cylinder 3 comprises an open-ended tube 6 of stainless steel disposed between upper and lower end structures 7, 8 of moulded plastics material, which close the ends of the tube. The components 6, 7, 8 are clamped securely together by tie-bolts 9 provided with butterfly nuts 10. The ends of the tube 6 are sealed by "0" rings 15, 16 disposed in grooves formed in the end structures 7, 8. The end structures 7, 8 are formed with internal flow ducts 25, 26 leading to external flow connections 27, 28. The jacket 4 is defined between an annular recess 35 formed in the upper end structure 7 and that part of the tube 6 which it surrounds. An "0" ring 36 disposed within a groove formed in the structure 7 seals the lower end of the jacket 4. <IMAGE>

Description

IMPROVEMENTS IN OR RELATING TO BEVERAGE DISPENSING PUMPS This invention relates to beverage dispensing pumps and is primarily, but not exclusively, concerned with beer dispensing pumps, usually referred to as beer engines".

According to the invention, a beverage dispensing pump comprises a piston movable within a cylinder, wherein at least one end of the cylinder incorporates an external jacket within which heat transfer fluid may be circulated.

When the cylinder is disposed in a substantially vertical position, the upper end of the cylinder will incorporate the jacket.

Preferably, the cylinder comprises an open-ended tube disposed between two end structures, which close the ends of the tube, the jacket then being defined by the tube and one of the structures.

Circulation of heat transfer fluid, for example chilled water, is used to maintain beverage within the cylinder at a substantially constant temperature.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a side view, in medial section, of a beer dispensing pump; and Figure 2 is a fragmentary side view, in medial section, which illustrates a modification.

With reference to Figure 1, a beer dispensing pump 1 in the form of a beer engine comprises a dispensing piston 2 movable within a cylinder 3, which is disposed substantially vertical.

The upper end of the cylinder 3 incorporates an external jacket 4 within which heat transfer fluid is circulated. The heat transfer fluid is chilled water which enters and leaves the jacket 4 by way of a pair of spaced apart inlet and outlet ducts 5, only one of which, namely the inlet duct, is shown.

The pump cylinder 3 comprises an open-ended tube 6 of stainless steel disposed between upper and lower end structures 7, 8 of thermally insulating plastics material, which close the ends of the tube. The components 6, 7, 8 are clamped securely together by tie-bolts 9 provided width butterfly nuts 10. The ends of the tube 6 are sealed by ~0~- rings 15, 16 disposed in grooves formed in the end structures 7, 8.

The piston 2 is moved within the cylinder 3 by a piston rod 17 which passes through a bearing 18 incorporated in the upper end structure 7. The bearing 18 is held in place by several bolts 19.

The piston 2, which is of plastics material, is formed with a ring of through ports 20, normally closed by a disc or plate valve 21 which rests on the upper surface of the piston 2. The periphery of the plate valve 21, which is of elastomer material, forms a seal with the bore of the tube 6.

The end structures 7, 8 are formed with internal flow ducts 25, 26 leading to external flow connections 27, 28.

The jacket 4 is defined between an annular recess 35 formed in the upper end structure 7 and that part of the tube 6 which it surrounds.

An 0~ ring 36 disposed within a groove formed in the structure 7 seals the lower end of the jacket 4.

An external sleeve 37 of thermal insulating material encloses that portion of the tube 6 which does not form part of the jacket 4. The material (polyacetal) of the end structures 7, 8 provide further thermal insulation.

In operation, upward movement of the piston 2 displaces beer through the duct 25 and external connection 27. Downward movement of the piston 2 causes beer trapped below the piston to pass through the ports 20 and deflect the plate valve 21 en route. The connection 28 incorporates a non-return valve to prevent backflow.

Chilled water supplied by a pumped source, not shown, is circulated through the jacket 4 at a temperature whereby beer is dispensed at a substantially even temperature, say 12"C to 15"C.

Otherwise, beer would be dispensed at ambient or room temperature, which could be as warm as 33"C.

The flow of chilled water within the jacket 4 may be controlled to regulate the temperature of beer being dispensed. For example, by use of a temperature-sensitive element, such as a thermostat, so as to directly control flow through the jacket 4. Alternatively, an on/off switch element could be used to control a circulating pump.

In the example illustrated, where the tube 6 has a bore of 72.00 mm and a length of 100.00 mm, the width of the jacket 4 is 0.75 mm and the depth thereof is 22.00 mm.

The dimensions of the jacket 4 can be varied, in order to suit requirements. This can be done by increasing the width of the recess 35 and/or the depth thereof.

In the example illustrated, the upper or warm end of the pump 1 is provided with the jacket 4. This is because natural convection causes the upper end of the pump 1 to be warmer than its lower end.

Should the pump 1 need to be disposed substantially horizontally, a pair of jackets 4 may be provided, disposed at opposite ends of the pump. Alternatively, the width and/or depth of recess 35 may be adjusted to enable one jacket only to be used.

The pump 1 illustrated by Figure 1 has a jacket 4 formed integrally with the end structure 7, which is a neat and inexpensive arrangement.

The modified pump la illustrated by Figure 2, has a jacket 4a formed by an annular block 40 clamped, by a ring of bolts indicated by lines 41, to a modified end structure 7a. A ring seal 42 is disposed between the block 40 and end structure 7a. The block 40 incorporates inlet and outlet ducts 5a for circulation of the chilled water.

Alternatively, another seal, namely O ring seal 43, may be substituted for ring seal 42. In this case, the cooling jacket again comprises a block attached to the cylinder 6 independently of, i.e.

not forming part of, the end structure 7.

Claims

1. A beverage dispensing pump comprising a piston movable within a cylinder, wherein at least one end of the cylinder incorporates an external jacket within which heat transfer fluid may be circulated.

2. A pump as claimed in Claim 1, wherein the cylinder comprises an open-ended tube disposed between two end structures, which close the ends of the tube, the jacket then being defined by the tube and one of the structures.

3. A pump as claimed in Claim 2, wherein the jacket comprises a recess formed in said one of the structures.

4. A pump as claimed in Claim 2, wherein the jacket comprises a recess formed in a block secured to said one of the structures.

5. A pump as claimed in Claim 2, wherein the jacket comprises a recess formed in a block which is independent of either of said structures.

6. A pump as claimed in any one of Claims 1 to 5, wherein, in operation, the cylinder is disposed in a substantially vertical position, the upper end of the cylinder then incorporating the jacket.

7. A pump as claimed in any one of Claims 1 to 5, wherein, in operation, the cylinder is disposed in a substantially horizontal position, with opposite ends of the cylinder each incorporating an external jacket.

8. A pump as claimed in any one of Claims 2 to 7, wherein the tube is of metal and the two end structures are of plastics material.

9., A pump as claimed in any one of Claims 2 to 8, wherein the cylinder is provided with an external sleeve of thermal insulating material enclosing that part of the tube which does not form part of the jacket.

10. A pump as claimed in any one of Claims 1 to 9, provided with means for controlling the flow of heat transfer fluid within the jacket.

11. A beverage dispensing pump, substantially as hereinbefore described, with reference to Figure 1 of the accompanying drawings.

12. A beverage dispensing pump, substantially as hereinbefore described, with reference to Figure 1 of the accompanying drawings, modified substantially as hereinbefore described with reference to Figure 2 of said drawings.