GB2162619A - Liquid dispensing tap - Google Patents

Abstract

A liquid dispensing tap comprises a main passage (2) for the supply of the liquid, a restricted passage (20) enabling froth to be formed and dispensed and valve means (8,22) controlling both passages (2,20) such that the restricted passage (20) can be maintained open while the main passage (2) is closed. A second arrangement, Figure 2, not shown, has the valve member as a sliding seal (68) of the main passage and an annular seal (57) sealing the restricted passage. <IMAGE>

Description

SPECIFICATION Liquid dispensing tap This invention relates to a liquid dispensing tap.

The tap of the invention is particularly suitable for use in dispensing beers.

In the field of beer dispensing, beers are usually supplied in kegs which are housed either in a cellar or, in some cases, under the bar itself. The beer is raised to the dispensing tap by means of a gas under pressure, usually CO2, or by means of manual or electric pumps.

In many cases, it is desired to serve beer with a head of froth as this is often found to be more acceptable to customers. This, however, often proves to be difficult for a number of reasons.

Firstly, if the beer is naturally highly carbonated as is the case, for example, with some lagers, they need to be dispensed at a relatively high pressure and any small constriction will produce a large amount of froth and make the beer difficult to dispense at all. On the other hand, less aerated beers, or beers dispensed at relatively low pressure will require some assistance to produce a head by the use of restricted passageways etc, making dispensing time consuming. Furthermore, it is undesirable to have the beer frothing more than can be avoided, except when producing the head.

The present invention seeks to provide a liquid dispening tap which will enable normal dispensing but which will make it possible also to dispense a froth for the purpose of making a head on the liquid.

According to the invention, there is provided a liquid dispensing tap having a main passage for the supply of the liquids, a restricted passage enabling froth to be formed and dispensed and valve means controlling both passages such that the restricted can be maintained open while the main passage is closed.

Preferably the valve means comprise a main valve for controlling the flow of beer into the dispensing tap and a subsidiary valve for controlling the flow of beer in the main passage.

The restricted passage may comprise one or more bores which effectively bypass the subsidiary valve.

in a first embodiment of the invention, the valve elements of the main and subsidiary valves may be connected rigidly together, the subsidiary valve closing the main passage by sliding in a reduced diameter portion thereof. Alternatively the valve elements may be connected by means of a spring urged lost motion connection such that the main valve element may continue to move towards and away from its seat while the subsidiary valve remains sealed.

The restricted passages may be arranged to extend from the main passage prior to the position of the subsidiary valve as seen in the direction of beer flow, the main passage ending in the first spout and the restricted passage ending in a second spout. The second spout may be arranged coaxially around the first spout.

In a second embodiment of the invention, the valve elements of the main and subsidiary valves may be connected rigidly together, the main passage may comprise a tubular element open at both ends and the subsidiary valve element may comprise a cup like structure slidable on to one end of the tubular element to cap the tubular element and being slidable on the tubular element while maintaining it closed to permit opening and closing of the main valve element.

The restricted passage may surround the main passage, both passages ending in coaxial spouts.

The invention will now be described in greater detail, by way of example, with reference to the drawings, in which: Figure 1 is a sectional view of a first form of beer dispensing tap in accordance with the invention, and Figure 2 is a view similar to Figure 1 but showing a second form of tap in accordance with the invention.

The beer dispensing tap shown in Figure 1 comprises a main body 1 having a generally longitudinal passage 2 housing the tap operating mechanism 3. Beer is supplied to the longitudinal passages 2 by means of an inlet stem 5 having a connector 6 at its free end for connection to a beer feed line (not shown).

Attached to what is, in use, the lower end of the body 1 is a combined valve body and spout 6, attached thereto by means of a locking ring 7. The valve body part 8 is sealed to the body 1 by an "0" ring seal 9. The valve body part 8 is provided at its upper end with a main valve seat 10 and at its lower end with a subsidiary valve seat 11 formed by a narrowed portion 12 of the combined valve body and spout 6, this narrowed portion 12 extending downwardly to form the spout 14.

Surrounding this spout 14 and spaced therefrom, is a spout cover 15. The spout cover 15 is screwed or otherwise located around the valve body part 8 and is sealed thereto by means of an "0" ring seal 17. The valve body part 8 has a central bore 19 bored with a plurality of narrow side bores 20 which run from a position just above the valve seat 11 into the space between the spout 14 and the spout cover 15.

Situated within the body 1 and the valve body and spout 6 is a valve element 22. This valve element 22 comprises an upper wide portion 23 in the region of the inlet stem 5. An "0" ring seal 24 is provided at the upper part of the portion 23 and an "0" ring seal 25 at the lower end cooperates with the valve seat 10.

Beneath the wide portion 23 is a reduced diameter portion 27 which is spaced from the walls of the central bore 19 so that the beer can pass along the central bore around the portion 27. Connected to the reduced diameter portion 27 is an even smaller diameter portion 28 which carries an "O" ring seal 29 cooperating sliding fashion with the subsidiary valve seat 11.

The valve element 22 is slidable up and down in the passage 2 and bore 19 under the control of the operating mechanism 3. This operating mechanism 3 comprises a rod 31 which engages in a recess 32 the portion 23 of the valve element 22 such that the rod 31 can rotate but any longitudinal movement of the rod 31 will entrain the valve element.

The rod 31 carries a male cam 33 which cooperates with a female cam 34 fixedly secured in the passages 2. The cams are so arranged that rotation of the rod 31 will raise and lower the valve element 22. The upper end of the passage 2 is closed by a top cap 35 secured to the body 1 by a nut 36 and providing a bearing for the rod 31. A spring 38 is provide for maintaining the cams in engagement. An operating handle for the rod 31 is usually attached to the rod 31 at 39.

The operation of the above dispenser top will now be described: With the connector 6 connected to this beer feed line and with the mechanism as shown, passage of beer is prevented by the engagement of the "0" ring seal 25 with the main valve seat 10.

To dispense beer from the spout 14, the handle "not shown" is rotated. As a result, the rod 31 is rotated and is caused to move vertically by the cams 33 and 34.

This movement will raise the valve element 22 so that the "0" ring seal 25 disengages from the seat 10 and the "0" ring seal 29 leaves its seat 11.

The beer can then flow around the portion 27 of the valve element, around the portion 28 thereof and out through the spout 14 into a waiting glass.

When the glass is nearly full, the handle is moved back towards its starting point, lowering the valve element until the "0" ring seal 29 slides into the subsidiary valve seat 11 and cuts off flow through spout 14.

Beer under pressure is, however, still present in the part of the bore 19 above the subsidiary valve seat and will now escape through the narrow side bores 20 into the spaces between the spout cover 15 and the spout 14. It will then be dispensed around the outside of the spout 14. Because of the reduced diameter bores 20 and the change of direction provided by the spout cover 15, the beer will be frothed and come to lie on top of the beer in the glass as a head.

Once the head has been formed, the handle is returned to its original position, engaging the "0" ring seal 25 with the main valve seat 10 to cut off the supply of beer altogether.

It will be understood that, due to the relative dimensions of the bores 20 and the spout 14, little or no froth will be produced during the straight dispensing operation.

A second embodiment of beer dispensing tap is shown in Figure 2. As in the first embodiment, the tap comprises a main body 51 having a generally longitudinal passage 52 housing the tap operating mechanism 53. Again, beer is supplied to the longitudinal passage 52 by means of an inlet stem 54 having a connector 55 at its free end for connection to a beer feed line (not shown).

Attached to what is, in use, the lower end of the body 51 is a combined valve body and spout assembly 56 which is a push fit on the body 51. The assembly 56 comprises an inner tubular element 58, forming a main passage which terminates, at its lower end in a spout 59. Surrounding this tubular element 58 is a two part sheath comprising an upper part 61 connected to the body 51 and a lower part 62 forming a spout 63 coaxial with the spout 59. The tubular element 58 and the upper part 62 of the sheath are held spaced apart by two spiders 64, suitably formed integrally with the tubular element 58. The two parts of the sheath are suitably sealed together using an "0"-ring seal 66.

The assembly 58 is provided with a main valve seat 67 formed by an upper edge of the upper sheath part 61 and a subsidiary valve seat 68 formed by the upper end of the tubular element 58.

Situated within the valve body 51 and extending a short distance into the combined valve body and spout 56 is a valve element 72. This valve element 72 is in the form of a tubular member 73 located in the region of the inlet stem 54. An "O"-ring seal 71 is provided at the upper part of the member 73 and an "O"-ring seal 74 cooperates with the valve seat 57 to form the subsidiary valve.

The lower end of the member 73 is formed with a tubular recess 75 which provides a cup like portion 76 which sits on the upper end of the inner tubular element 58 so as to be slidable thereon and cooperates with the valve seat 68 to form the main valve.

It will be seen that the member 73 has a slightly smaller external diameter than the internal diameter of the upper portion 61 of the outer sheath so that beer can flow around the valve member 73 when the cup like portion of the valve member 73 is in engagement with the tubular member 58.

The valve element 73 is slidable up and down in the passage 52 under control of the operating mechanism 53. The operating mechanism 53, as in the first embodiment, comprises a rod 81 which engages in a recess 82 in the upper part of the valve element 73 such that the rod can rotate but any longitudinal movement thereof will entrain the valve element 73. The rod 81 carries a male cam 83 which cooperates with a female cam 84 fixedly secured in the passage 52. The upper end of the passage 52 is closed by a top cap 85 and a spring 88 is provided for maintaining the cam surfaces in engagement. An operating lever (not shown) is usually attached to the rod 81 at 89.

The operation of the second embodiment of dispenser tap will now be described: With the mechanism arranged as shown, beer from the stem 54 is prevented from being dispensed by the engagement of the "O"-ring seal 74 with the main valve seat 57.

To dispense beer through the spout 59, the rod 81 is rotated by the handle and is caused to move vertically upwards by the cams 83 and 84. This raises the valve element 73 and disengages the "O"-ring seal 74 from its seat 57 and removes the cup-like portion of the valve element 73 from the upper end of the inner tubular member 58. Beer can thus flow around the valve element and down through the member 58 into a waiting glass.

As the glass becomes nearly full, the rod 81 is rotated back towards its starting point. This lowers the valve member 73 down so that the cup-like portion surrounds the inner tube 58, without, at this point, causing engagement between the "0"ring seal 74 and its seat 57. No more beer can therefore gain access to the inner tube 58.

Beer under pressure can, however, be forced down the restricted passageway left around the valve element 73 and into the spout 63 to be dispensed. However, because of the restricted passageway, it will emerge as a froth and so form a head on the previously dispensed beer.

Once the head has been formed, the rod 81 is returned by its handle to its original position and the main valve will be closed to shut off the supply of beer entirely.

It is to be understood that due to the relative dimensions of the main and restricted passageways, although the retricted passageway will remain open during the main dispensing operation, little or no froth will be dispensed.

It will be appreciated that various modifications may be made to the above described embodiment without departing from the scope of the invention.

For example, the rotary arrangement of the rod 31 could be replaced by a purely longitudinal movement of the rod operated by a handle which is raised and lowered about a pivot and is pivotally connected to the rod.

The narrow bores 20 could be replaced by bores in the valve element which bypass the "0" ring seal 29 and permit dispensing of the head through the spout 14, thus doing away with the need for a spout cover 15.

Furthermore, the subsidiary valve seat 11 could be replaced with a valve seat similar to that provided at 10, the two parts of the valve element being connected together with limited free movement or lost motion between them, a spring being provided to urge the subsidiary valve element into contact with its seat. Such an arrangement would avoid the need of a sliding fit at the subsidiary valve seat 11.

In an alternative arrangement, not shown, the longitudinal arrangement is replaced by a rotary arrangement. The rotary valve member is provided with a main channel and a "froth" channel which are connected up at different positions of the valve. The main channel suitably feeds an inner spout while the "froth" channel feeds the outer channel.

It will be seen that the above described embodiments provide a beer or other liquid dispensing tap which will allow straight dispensing of liquid as well as the ability to form a head on the top of the liquid after the straight dispensing operation.

Claims (10)

1. A liquid dispensing tap comprising a main passage for the supply of the liquid, a restricted passage enabling froth to be formed and dispensing and valve means controlling both passages such that the restricted passage can be maintained open while the main passage is closed.

2. A tap as claimed in claim 1, wherein the valve means comprises a main valve for controlling the flow of liquid into the dispensing tap and a subsidiary valve for controlling the flow of liquid into the main passage.

3. A tap as claimed in claim 2, wherein the restricted passage comprises one or more bores which effectively bypass the subsidiary valve.

4. A tap as claimed in claim 2 or 3, wherein the valve elements of the main and subsidiary valves are connected rigidly together, the subsidiary valve closing the main passage by sliding in a reduced diameter portion thereof.

5. A tap as claimed in claim 2 or 3, wherein the valve elements of the main and subsidiary valves are connected together by a spring urged lost motion connection such that the main valve element may continue to move towards and away from its seat while the subsidiary valve remains in the closed position.

6. A tap as claimed in any one of claims 1 to 5, wherein the restricted passage extends from the main passage prior to the position of the subsidiary valve as seen in the direction of liquid flow, the main passage ending in a first spout and the restricted passage ending in a second spout.

7. A tap as claimed in claim 6, wherein the second spout is arranged coaxially around the second spout.

8. A tap as claimed in claim 2 or 3, wherein the valve elements of the main and subsidiary valves are connected rigidly together, the main passage comprises a tubular element open at both ends and the subsidiary valve element comprises a cup like structure slidable on to one end of the tubular element to cap the tubular element and being slidable on the tubular element while maintaining it closed to permit opening and closing of the main valve element.

9. A tap as claimed in claim 8, wherein the restricted passage surrounds the main passage, both passages ending in coaxial spouts.

10. A liquid dispensing tap substantially as described herein with reference to the drawings.