GB1599528A

GB1599528A - Dispensing heads

Info

Publication number: GB1599528A
Application number: GB4988477A
Authority: GB
Original assignee: KONSTRUKTIE J LAMBRECHTS PVBA
Current assignee: KONSTRUKTIE J LAMBRECHTS PVBA
Priority date: 1977-11-30
Filing date: 1977-11-30
Publication date: 1981-10-07
Also published as: CA1093516A; BE872168A

Description

(54) IMPROVEMENTS IN OR RELATING TO DISPENSING HEADS (71) We,KONSTRUKTIE J. LAMBRECHTS p.v.b.a., a Belgium company, of Gansbroekstraat 25, 2658 Ruisbroek aan de Rupel, Belgium, do hereby declare this invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described, in and by the following statement.

This invention relates to dispensing heads.

More particularly, the invention relates to dispensing heads of the kind adapted to be fitted to a container having a valve plunger with which the di dispensing head co-operates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, the dispensing head having inlet means for connection to a source of the pressurising gas and outlet means for connection to a dispensing tap.

The invention is particularly, though not exclusively, applicable to dispensing heads for use with kegs from which beer or lager is dispensed under pressure of carbon dioxide supplied through the dispensing head, the dispensing head being connected to a pipe which feeds the beer to a dispensing tap. Such installations are widely used, for example in public houses and restaurants.

A disadvantage of such installations known hitherto is that the dispensing heads and the pipework through which the beer or other beverage is fed from the keg required frequent cleaning.

It is an object of this invention to provide a dispensing head which enables the head and the associated pipework to be periodically rinsed with water or other suitable fluid.

This invention includes a dispensing head adapted to be fitted to a container having a valve plunger with which the dispensing head cooperates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, the dispen- sing head having gas inlet means for connection to a source of the pressurising gas and outlet means for connection to a dispensing tap, rinsing fluid inlet means adapted to be connected to a source of rinsing fluid, valve means in the dispensing head movable between a first position in which the rinsing fluid inlet means is closed, the gas inlet means is in communication with the interior of the container to which the dispensing head is fitted and the outlet means is in communication with the interior of the container through the valve plunger so that liquid is dispensed from the container, and a second position in which the outlet means is disconnected from the interior of the container and placed in communication with the rinsing fluid inlet means so that rinsing fluid flows through the outlet means, and control means for moving the valve means from the second to the first position independently of the supply of gas to the gas inlet means.

Suitably, the valve means comprises a valve member vertically movable in a body of the dispensing head between a first position in which, in use, the valve member engages the valve plunger and holds it in its open position and a second position in which the valve member is disengaged from the valve plunger.

In accordance with a preferred feature of the invention, use is made of the pressure of the gas or of the rinsing fluid to move the valve member. Thus, in one form of the invention, the valve member includes a piston movable in a cylinder forming part of the body of the dispensing head, and an inlet to the cylinder is adapted to be connected to the source of pressurising gas so that the pressure of the gas, in use, urges the valve member to its first position.

However, in a preferred form of the invention, the pressure of the rinsing fluid is used to move the valve member. Thus, the invention also includes a dispensing head adapted to be fitted to a container having a valve plunger with which the dispensing head co-operates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, the dispensing head having gas inlet means for connection to a source of the pressurising gas and outlet means for connection to a dispensing tap, first rinsing fluid inlet means adapted to be connected to a source of rinsing fluid, a valve member movable in the dispensing head between a first position in which the rinsing fluid inlet means is closed, the gas inlet means is in communication with the interior of the container to which the dispensing head is fitted and the outlet means is in communication with the interior of the container through the valve plunger so that liquid is dispensed from the container, and a second position in which the outlet means is disconnected from the interior of the container and placed in communication with the rinsing fluid inlet means so that rinsing fluid flows through the outlet means, and control means for moving the valve member from the second to the first position, the control means comprising a piston connected to the valve member and movable in a cylinder forming part of the dispensing head, and second rinsing fluid inlet means adapted to be connected to the source of rinsing fluid and opening into the cylinder so that on supply of rinsing fluid to the second rinsing fluid inlet means the pressure of the rinsing fluid acting on the piston urges the valve member to its first position.

Preferably, the first rinsing fluid inlet means is in communication with the cylinder so that when rinsing water is supplied to the first rinsing fluid inlet means whilst supply of rinsing water to the second rinsing fluid inlet means is cut off, the pressure of rinsing water supplied to the first rinsing fluid inlet means urges the valve member to its second position. Suitably, the first rinsing fluid inlet means is, when the valve member is in its second position, connected to the outlet means through the cylinder.

Suitably, the valve member has a longitudinal channel providing the outlet means, and a oneway valve is positioned in the channel to prevent rinsing fluid from entering the container to which the head is fitted.

The invention also includes an installation for dispensing liquid from a container, comprising a dispensing head as defined above, a source of pressurising gas connected to the gas inlet means, a source of rinsing fluid connected to the rinsing fluid inlet means, a dispensing tap connected to the outlet means through a length of delivery pipe, and control means operable from a position close to the dispensing tap for controlling the position of the valve means independently of the supply of gas to the gas inlet means.

Where the valve means is controlled as defined above by means of a supply of the pressurising gas or of the rinsing fluid to the control inlet of a cylinder forming part of the dispensing head, the control means may include a control valve through which the source of pressurising gas or of rinsing fluid is connected to the control inlet. The control valve may be a manually operated valve positioned close to the dispensing tap. Alternatively, the control valve may be positioned in the region of the dispensing head and source of pressurising gas, the control valve being operated from near the dispensing tap, for example by a further valve connected in a branch line between the source of pressurising gas and the control valve, or by electromagnetic means, the latter being particularly suitable when there is a long distance between the dispensing head and the dispensing tap.

The control valve is preferably also arranged to interrupt the supply of rinsing fluid to the dispensing head. This eliminates the risk of leakage of fluid in the dispensing head contaminating the liquid to be dispensed and is particularly useful when the source of rinsing fluid is at high pressure.

The use of the pressure of the rinsing fluid to control the position of the valve member has the advantage that, when the dispensing head is fitted to an existing installation, there is no need to modify the existing conduit from the gas supply.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which like elements have been given the same reference numerals and in which: Figure 1 is a side elevation of a dispensing head constructed in accordance with a first embodiment of the invention, Figures 2 and 3 are vertical sections through the dispensing head of Figure 1, showing a valve member of the head in its lowermost and uppermost positions respectively, Figures 4, 5 and 6 show respectively three installations in accordance with this invention, employing the dispensing head of Figures 1 to 3, Figures 7 and 8 are vertical cross sections through a dispensing head according to a second embodiment of this invention, Figures 9 and 10 are vertical sections through a dispensing head in accordance with a third embodiment of the invention, showing a valve member of the head in its lowermost and uppermost positions respectively, Figure 11 shows an installation employing the dispensing head of Figures 9 and 10, Figures 12 and 13 are fragmentary vertical sections through dispensing heads modified to co-operate with two different keg tapping systems.

Referring to Figures 1 to 3, the dispensing head 10 comprises an adaptor 12 for connection to the tapping hole of a keg, a body 14 fixed to the adaptor and surmounted by a cylinder 16, and a valve member 18 vertically movable relative to the adaptor 12, body 14 and cylinder 16, the valve member having a longitudinally extending channel 20.

The adaptor 12 is shaped to fit onto the mouth of a keg, and the lower part of the valve member 18 is shaped to engage the valve plunger forming part of the keg, when the valve member is in its lowermost position, so that beer from the keg can flow through the channel 20 of the valve member. The various keg tapping systems in use, and the shape of the adaptor and lower part of the valve member necessary for use with each system, will be well known to those skilled in the art.

The adaptor 12 is formed in the usual way wih a lateral inlet 22 to which can be connected a pipe supplying carbon dioxide gas under pressure, the gas entering the adaptor through a non-return valve 24 (Figure 4). When the valve member 18 is in its lowermost position (as shown in Figure 2) the inlet 22 is, in use, in communication with the interior of the keg, whilst when the valve member is in its upper.

most position (as shown in Figure 3) the inlet 22 is closed by engagement of the valve member with 0-ring 26.

Fixed to the valve member 20 is a piston 28 which moves in the cylinder 16, engagement of the piston with the top and bottom internal fces of the cylinder defining the uppermost and lowermost positions of the valve member.

An inlet 30 which can be connected to a pipe supplying carbon dioxide under pressure, as described below, opens into the interior of the cylinder 16 at a point above the piston 28, so that supply of gas through the inlet 30 applies pressure to the piston to move the valve member to its lowermost position. The interior of the cylinder 16 below the piston 28 is open to the atmosphere through an aperture 32. The upper part of the valve member 18 forms an outlet 46 to which can be connected a pipe 50 leading to a dispensing tap 52.

A further inlet 34, which can be connected to a source of rinsing water, opens into an annular channel 36 formed in the inside wall of the body 14 of the dispensing head. When the valve member 18 is in its uppermost position the channel 36 is placed in communication with the channel 20 of the valve member 18 through a bore 38 through the wall of the valve member. When, in use, the valve member is in this position the pressure of rinsing water entering the channel 20 moves the ball 40 of a one-way ball valve provided in the valve member 18 to a lowermost position in which the ball engages a valve seating 42 to prevent the rinsing water from entering the keg. When the valve member 18 is moved to its lowermost position the bore 38 is moved out of alignment with the channel 36 so that the inlet 34 is closed as well as the bore 38.In this position, the ball 40 can be lifted from its seating by pressure of liquid flowing from the keg, the ball moving against a retaining cage 44.

Figure 4 shows an installation employing the dispensing head of Figures 1 to 3.

The dispensing head 10 is fitted to a keg 48, and the outlet 46 is connected through the pipe 50 to the dispensing tap 52, which is of conventional construction. The pipe 50, which preferably has a maximum interior diameter of 10 mrn, may pass in the usual way through a chilling system. The inlet 22 of the adaptor 12 is connected through suitable piping to a cylinder 54 of compressed carbon dioxide, and the inlet 30 the cylinder 16 of the dispensing head 10 is connected to the same carbon dioxide cylinder through a T-junction 56 and a twoposition tap 58 which is located near to the dispensing tap 52. The inlet 34 to the body 14 of the dispensing head is connected through a stopcock 50 to a source of rinsing water which may for example be mains water. The connections to the various pipes are made through suitable unions in the usual way.

In operation of the installation shown in Figure 4, before the dispensing head is fitted to a full keg, the two-position tap 58 is placed on the "rinsing" position, i.e. the closed position in which no gas is supplied to the cylinder 16. The valve member 18 therefore remains in its uppermost position so that water can enter the channel 20 through inlet 34 and bore 38. The dispensing tap 52 is opened, and rinsing water flows through channel 20, pipe 50 and tap 52. The dispensing head is then fitted to the keg in the usual manner. The twoposition tap 58 is then moved to the "dispensing" position, i.e. to the open position in which gas is supplied from the carbon dioxide cylinder 54 to the inlet 30 of cylinder 16.The valve member 18 is thus moved to its lowermost position, the valve plunger incorporated in the keg is opened and gas is supplied through inlet 34 to the interior of the keg as described above so that beer flows through channel 20 and through pipe 50 to the dispensing tap 52. At the same time the rinsing water inlet 30 is closed. Since the rinsing water is automatically cut off as the plunger valve of the keg is opened and as gas inlet 32 is opened, and since the volume between the water inlet and the ball valve 40 is very small, the beer follows the water flowing in pipe 50 without interruption and with no danger of the water mixing with the beer or of an airlock forming in the pipe.

With the two-position tap 58 in the "dispensing position", the dispensing tap 52 is used to control the flow beer from the keg in the usual manner.

When the keg is empty, and the dispensing head is to be connected to a new keg, the twoposition tap 58 is placed in the "rinsing" position, so that the gas pressure to cylinder 16 is cut off. The valve member 18 is consequently moved to its uppermost position under the internal pressure of the keg. The valve member 18 is thus automatically detached from the valve plunger of the keg, and the supply of gas through inlet 22 in adaptor 12 is cut off.

At the same time the water inlet is opened so that rinsing water flows through the dispensing head and the pipe 50. The dispensing head is then connected to the new keg, and the twoposition tap is moved back to the "dispensing" position to cut off the rinsing water and connect the valve member 18 to the valve plunger of the new keg, as described above.

Since it is necessary to move the two-position tap 58 to the "dispensing" position before the dispensing head is removed from the empty keg, the dispensing head cannot be moved from an empty keg to a full keg without rinsing water automatically flowing through the dispensing head and pipe 50. It is therefore ensured that the dispensing head and pipe are rinsed at least at every change of keg. Also, since the valve member is in its uppermost position there is no danger of leakage of carbon dioxide from the head as it is moved from the empty keg to the new one, and leakage of water is prevented by the valve 40.

In addition, the dispensing head can be operated to rinse the head and pipe 50 and to disconnect the valve member 18 from the keg whenever there is a prolonged interruption in delivery from the keg, overnight for example.

To do this, the two-position tap 58 is placed in the "rinsing" position and the dispensing tap 52 is opened until water flows from the dispensing tap. The dispensing tap 52 is then closed, and the two-position tap is left in the "rinsing" position. The valve member 18 is then disconnected from the valve plunger and water remains in the dispensing head and pipe 50 until the two-position tap 58 is again placed in the "dispensing" position when delivery of beer is to be recommenced. It will be apparent that the operations just described can be carried out from a position near the dispensing tap, without the operator having to go to the cellar or room housing the kegs and carbon dioxide cylinder and associated equipment.

In the dispensing head shown in Figures 1 to 3, leakage of water or gas between the outer wall of the movable valve member 18 and the inner walls of the adaptor 12, body 14 and cylinder 16 is prevented by the use of a number of suitably positioned 0-rings 60. However, if the supply of rinsing water is at a high pressure, there may be a danger of leakage of water from inlet 32 when the valve member is in its lowermost position if one or more of the 0-rings fails. Figure 5 shows an altemative installation which is particularly useful in those circumstances, though it can of course also be used where the water pressure is not high.

In the installation of Figure 5, the pipe from the water supply is connected to one inlet 64 of a control valve 62 the corresponding outlet 66 of which is connected to the rinsing water inlet 34 of the dispensing head 10, which is identical to that of Figures 1 to 3. The main pipe from the carbon dioxide cylinder is connected to a further inlet 68 of the control valve 62, the corresponding outlet 70 being connected to both the gas inlets 22 and 30 of the dispensing head. The control valve 62 is a spool valve the spool of which is biassed by spring 72 to a position in which the water inlet 64 and outlet 66 are closed whilst the gas inlet 68 and outlet 70 are open, so that the valve is normally-open to gas flowing to the dispensing head but normallyclosed to water.The spool can be moved from its normal position, to cut off the gas supply to the dispensing head and open the water supply to the head, under pressure of gas supplied to a control inlet 74 at the end of the control valve 62 through the two position tap 58 which, as in the installation of Figure 4, is positioned close to the dispensing tap 52 and is connected through a branch pipe to the carbon dioxide cylinder. In the installation of Figure 5 the "dispensing" position of the tap 58 is the closed position in which no gas is supplied to the control inlet 74 of the control valve so that gas is supplied through the control valve to the gas inlets of the dispensing head to allow beer to be dispensed as described above. At the same time the water supply is disconnected by control valve 62 so that there is no danger of water leaking under pressure in the dispensing head 10.The "rinsing" position of the tap 58 is the open position in which gas is supplied to the control inlet 74 of control valve 62 to move the spool to the position cutting off the gas supply to the dispensing head and allowing rinsing water to flow to the dispensing head. It will be appreciated that even if the gas supply from the carbon dioxide cylinder fails, so that the valve member 18 of the dispensing head moves to its uppermost position, the control valve 62 will cut off the supply of water to the dispensing head since the spool will be moved to its normal position by spring 72.

Figure 6 shows a further alternative installation which is the same as that of Figure 5 except that the two-position valve 58 is replaced by an electric control switch 76 which controls a solenoid-operated valve 78 through which the branch line from the carbon dioxide cylinder is connected to the control inlet of control valve 62. This installation is particularly useful when there is a long distance between the dispensing tap and the room housing the kegs and carbon dioxide cylinder, since it avoids a long run of gas piping.

Figures 7 and 8 show a second embodiment of the invention, in which the main elements of the dispensing head are essentially the same as those of the embodiment of Figures 1 to 3.

However, an additonal gas inlet 31 to the cylinder 16 is provided to enable gas to be supplied to the cylinder 16 below the piston 28 so that the valve member 18 can be moved positively to its upper position. The head can be used in an assembly similar to that of Figure 4, 5 or 6, suitable additional control valves being provided to control the supply of gas to the additional control inlet 31.

Figures 7 and 8 also illustrate the provision of a handle 80 to enable the automatic rinsing opertion to be overridden manually. The handle 80 is pivotable between a first position (Figure 7) in which it does not interfere with the movement of the valve member 18 and a second position (Figure 8) in which a collar 82 sliding on an extension of valve member 18 engages an abutment 84 on the valve member 18 to hold it in its lowermost position.

Figures 9 and 10 show a third embodiment of the invention in which the pressure of the rinsing water is used, instead of the pressurising gas, to move the valve member 18. The dispensing head of this embodiment has an adaptor 12, body 14, cylinder 16 and valve member 18 to which is fixed a piston 28, as in the previous embodiments. A gas inlet 22 and beer outlet 48 are also provided as in the previous embodiments, but the control inlet 30 and rinsing water inlet 32 of the previous embodiments are omitted.

In place of those inlets, a control inlet 90, which as described below is to be connected to a source of rinsing water, is formed in the cylinder 16 and communicates through a channel 92 with the interior of the cylinder above the piston 28. A second, rinsing inlet 94 opens into the cylinder 16 below the piston 28. When the valve member 18 is in its uppermost position as shown in Figure 10 the interior of cylinder 16 below the piston is in communication with the central channel 20 of the valve member through a bore 96 in the valve member, so that rinsing water supplied to the inlet 94 can flow into the channel 20. When the valve member 18 is in its lowermost position as shown in Figure 9 the bore 96 is closed and water is prevented from leaking into channel 20 by an 0-ring 98.

A one-way ball valve is provided in the channel 20, the ball 40 of the valve being moved against a valve seating 42 by the pressure of rinsing water when the valve member 18 is in its uppermost position, to prevent rinsing water entering the keg. When the valve member 18 is in its lowermost position the ball 40 can be lifted from its seating by pressure of liquid flowing from the keg.

Figure 11 shows an installation employing the dispensing head of Figures 9 and 10. The dispensing head 10 is fitted to a keg 48, and the outlet 46 is connected through the pipe 50 to the dispensing tap 52, as in the assemblies of Figures 4 to 6. The inlet 22 of the adapter 12 is connected through suitable piping to a cylinder 54 of compressed carbon dioxide. The inlets 90 and 94 to the cylinder 16 of the dispensing head 10 are connected through respective pipes 102 to 104 to a manually operated valve 100 which is located near to the dispensing tap 52 and which is connected through a pipe 106 and stopcock 60 to a source of rinsing water which may for example be mains water. (The inlets 90 and 94 are shown on the same side of the cylinder 16 in Figure 11, for the sake of clarity). The connections to the various pipes are made through suitable unions in the usual way.

The manually operated valve 100 has two positions: a "dispensing" position in which the pipe 106 is connected to pipe 102, so that rinsing water is supplied to the control inlet 90, whilst the pipe 104 is connected to the vent 108, which is connected to a suitable drain, so that rinsing water inlet 94 is connected to the atmosphere, and a "rinsing" position in which pipe 106 is connected to pipe 104, so that rinsing water is supplied to the rinsing water inlet 94 whilst the supply of water to the control inlet 90 is cut off.

In operation of the installation shown in Figure 11, before the dispensing head 10 is fitted to a full keg, the manually operated valve 100 is placed in the "rinsing" position. Water therefore enters inlet 94 and moves the valve member 18 to its uppermost position so that the water can enter the channel 20 through inlet 94, cylinder 16 and bore 96. The dispensing tap 52 is opened, and rinsing water flows through channel 20, pipe 50 and tap 52.

The dispensing head is then fitted to the keg in the usual manner. The manually operated valve 100 is then moved to the "dispensing" position. Water is therefore supplied to inlet 90 and the pressure of water acting on piston 28 moves the valve member 18 to its lowermost position. The valve plunger incorporated in the keg is thus opened and gas is supplied through inlet 22 to the interior of the keg as described above so that beer flows through channel 20 and through pipe 50 to the dispensing tap 52.

At the same time the supply of rinsing water to channel 20 through bore 96 is cut off. The bore 96 is so positioned that when the valve member 18 is in its uppermost position it opens into a chamfered recess 110 in the lower face of cylinder 16, so that the bore is closed as soon as the valve member begins to move towards its lowermost position, the remaining water in the cylinder 18 below piston 28 being exhausted through pipe 104 and vent 108 to the drain.

Since the rinsing water is thus automatically cut off as the plunger valve of the keg is opened, and since the volume between the bore 96 and the ball valve 40 is very small, the beer follows the water flowing in pipe 50 without interruption and with no danger of the water mixing with the beer or of an airlock forming in the pipe. Moreover, when the valve 100 is in the "dispensing" position and the valve member 18 is in its lowermost position there is no danger of leakage of water into the channel 20, since the only path through which water can get to bore 96 is through the lower part of cylinder 16 which is connected through inlet 94 to the vent 108 and thus at atmospheric pressure.The pressure in channel 20, which is provided by the pressurising gas from cylinder 54, is greater than that in the lower part of cylinder 16, so that even in the unlikely event of failure both of 0-ring 98 and 0-ring 112 on piston 28 the water being supplied through inlet 90 could not enter bore 96 but would escape through inlet 94, so that the danger of contamination of the dispensed beer is eliminated.

When the keg is empty, and the dispensing head is to be connected to a new keg, the valve 100 is placed in the "rinsing" position, so that the supply of water to the upper part of cylinder 16 is cut off and water is supplied through inlet 94 to the lower part of the cylinder. The valve member 18 is consequently moved to its uppermost position under the pressure of water supplied through inlet 94 and the internal pressure of the keg, the water above piston 28 being exhausted through pipe 102 and vent 108.

The valve member 18 is thus automatically detached from the valve plunger of the keg, and the supply of gas through inlet 22 in adaptor 12 is cut off. At the same time the bore 96 is placed in communication with cylinder 16 so that rinsing water flows through the dispensing head and the pipe 50. The dispensing head is then connected to the new keg, and the valve 100 is moved back to the "dispensing" position to cut off the rinsing water and connect the valve member 18 to the valve plunger of the new keg, as described above.

As with the previous embodiments, it is necessary to move the valve 100 to the "dispensing" position before the dispensing head is removed from the empty keg, so that the dispensing head cannot be moved from an empty keg to a full keg without rinsing water automatically flowing through the dispensing head and pipe 50. It is therefore ensured that the dispensing head and pipe are rinsed at least at every change of keg. Also, since the valve member is in its uppermost position the inlet 22 is closed by engagement of the valve member with the 0-ring 26, so that there is no danger of leakage of carbon dioxide from the head as it is moved from the empty keg to the new one, and leakage of water is prevented by the valve 40.

It will be apparent that the dispensing head of Figures 9 to 11 can be operated in a similar manner to the previous embodiments to rinse the head and pipe 50 and to disconnect the valve member 18 from the keg whenever there is a prolonged interruption in delivery from the keg, such as overnight. To do this, the valve 100 is placed in the "rinsing" position and the dispensing tap 52 is opened until water flows from the dispensing tap. The dispensing tap 52 is then closed, and the valve 100 is left in the "rinsing" position until delivery of beer is to be recommenced.

It will be appreciated that the installation of Figure 11 could be modified in similar manner to that of Figure 6, i.e. by replacing the manuallysperated valve 100 with a solenoidoperated valve positioned in the cellar and controlled by an electric switch near the dispensing. The dispensing head of Figures 9 and 10 could also be modified by the provision of an override handle as in the embodiment of Figures 7 and 8.

As mentioned above, the adaptor 12 of the dispensing head of each embodiment can be modified to suit any of the various keg tapping systems in use. For example, Figures 12 and 13 illustrate the modified form of the adaptor for two such tapping systems.

In each of the installations described, the ease with which the dispensing head and the pipe leading to the dispensing tap can be rinsed, and the automatic rinsing at each change of keg, means that the periodic cleaning of the installation can be reduced considerably, or eliminated completely.

It will be appreciated that instead of water any other liquid suitable for rinsing could be used, a supply of the liquid under pressure being connected to the appropriate inlet or inlets of the dispensing head. It will also be appreciated that modifications could be made in the described embodiments. For example, other means could be provided for effecting the necessary movement of the valve member of the dispensing head, such as an electromagnetic device acting directly on the valve member and controlled from a switch near the dispensing tap.

WHAT WE CLAIM IS: 1. A dispensing head adapted to be fitted to a container having a valve plunger with which the dispensing head co-operates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, the dispensing head having gas inlet means for connection to a source of the pressurising gas and outlet means for connection to a dispensing tap, rinsing fluid inlet means adapted to be connected to a source of rinsing fluid, valve means in the dispensing head movable between a first position in which the rinsing fluid inlet means is closed, the gas inlet means is in communication with the interior of the container to which the dispensing head is fitted and the outlet means is in communication with the interior of the container through the valve plunger so that liquid is dispensed from the container, and a second position in which the outlet means is disconnected from the interior of the container and placed in communication with the rinsing fluid inlet means so that rinsing fluid flows through the outlet means, and control means for moving the valve means from the second to the first position independently of the supply of gas to the gas inlet means.

2. A dispensing head as claimed in claim 1, characterised in that the gas inlet means is closed when the valve means is in the second position.

3. A dispensing head as claimed in claim 1 or claim 2, in which the valve means comprises a valve member vertically movable in a body of the dispensing head between a first position in which, in use, the valve member engages the valve plunger and holds it in its open position and a second position in which the valve member is disengaged from the valve plunger.

4. A dispensing head as claimed in claim 3,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. head is to be connected to a new keg, the valve 100 is placed in the "rinsing" position, so that the supply of water to the upper part of cylinder 16 is cut off and water is supplied through inlet 94 to the lower part of the cylinder. The valve member 18 is consequently moved to its uppermost position under the pressure of water supplied through inlet 94 and the internal pressure of the keg, the water above piston 28 being exhausted through pipe 102 and vent 108. The valve member 18 is thus automatically detached from the valve plunger of the keg, and the supply of gas through inlet 22 in adaptor 12 is cut off. At the same time the bore 96 is placed in communication with cylinder 16 so that rinsing water flows through the dispensing head and the pipe 50. The dispensing head is then connected to the new keg, and the valve 100 is moved back to the "dispensing" position to cut off the rinsing water and connect the valve member 18 to the valve plunger of the new keg, as described above. As with the previous embodiments, it is necessary to move the valve 100 to the "dispensing" position before the dispensing head is removed from the empty keg, so that the dispensing head cannot be moved from an empty keg to a full keg without rinsing water automatically flowing through the dispensing head and pipe 50. It is therefore ensured that the dispensing head and pipe are rinsed at least at every change of keg. Also, since the valve member is in its uppermost position the inlet 22 is closed by engagement of the valve member with the 0-ring 26, so that there is no danger of leakage of carbon dioxide from the head as it is moved from the empty keg to the new one, and leakage of water is prevented by the valve 40. It will be apparent that the dispensing head of Figures 9 to 11 can be operated in a similar manner to the previous embodiments to rinse the head and pipe 50 and to disconnect the valve member 18 from the keg whenever there is a prolonged interruption in delivery from the keg, such as overnight. To do this, the valve 100 is placed in the "rinsing" position and the dispensing tap 52 is opened until water flows from the dispensing tap. The dispensing tap 52 is then closed, and the valve 100 is left in the "rinsing" position until delivery of beer is to be recommenced. It will be appreciated that the installation of Figure 11 could be modified in similar manner to that of Figure 6, i.e. by replacing the manuallysperated valve 100 with a solenoidoperated valve positioned in the cellar and controlled by an electric switch near the dispensing. The dispensing head of Figures 9 and 10 could also be modified by the provision of an override handle as in the embodiment of Figures 7 and 8. As mentioned above, the adaptor 12 of the dispensing head of each embodiment can be modified to suit any of the various keg tapping systems in use. For example, Figures 12 and 13 illustrate the modified form of the adaptor for two such tapping systems. In each of the installations described, the ease with which the dispensing head and the pipe leading to the dispensing tap can be rinsed, and the automatic rinsing at each change of keg, means that the periodic cleaning of the installation can be reduced considerably, or eliminated completely. It will be appreciated that instead of water any other liquid suitable for rinsing could be used, a supply of the liquid under pressure being connected to the appropriate inlet or inlets of the dispensing head. It will also be appreciated that modifications could be made in the described embodiments. For example, other means could be provided for effecting the necessary movement of the valve member of the dispensing head, such as an electromagnetic device acting directly on the valve member and controlled from a switch near the dispensing tap. WHAT WE CLAIM IS:

1. A dispensing head adapted to be fitted to a container having a valve plunger with which the dispensing head co-operates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, the dispensing head having gas inlet means for connection to a source of the pressurising gas and outlet means for connection to a dispensing tap, rinsing fluid inlet means adapted to be connected to a source of rinsing fluid, valve means in the dispensing head movable between a first position in which the rinsing fluid inlet means is closed, the gas inlet means is in communication with the interior of the container to which the dispensing head is fitted and the outlet means is in communication with the interior of the container through the valve plunger so that liquid is dispensed from the container, and a second position in which the outlet means is disconnected from the interior of the container and placed in communication with the rinsing fluid inlet means so that rinsing fluid flows through the outlet means, and control means for moving the valve means from the second to the first position independently of the supply of gas to the gas inlet means.

4. A dispensing head as claimed in claim 3,

in which the valve member includes a piston movable in a cylinder forming part of the body of the dispensing head, and an inlet to the cylinder is adapted to be connected to the source of pressurising gas so that the pressure of the gas, in use, urges the valve member to its first position.

5. A dispensing head as claimed in claim 4, in which a further inlet to the cylinder is adapted to be connected to the source of pressurising gas so that supply of gas to the further inlet whilst supply to the first-mentioned gas inlet means is cut off urges the valve member to its second position.

6. A dispensing head adapted to be fitted to a container having a valve plunger with which the dispensing head cooperates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, the dispensing head having gas inlet means for connection to a source of the pressurising gas and outlet means for connection to a dispensing tap, first rinsing fluid inlet means adapted to be connected to a source of rinsing fluid, a valve member movable in the dispensing head between a first position in which the rinsing fluid inlet means is closed, the gas inlet means is in communication with the interior of the container to which the dispensing head is fitted and the outlet means is in communication with the interior of the container through the valve plunger so that liquid is dispensed from the container, and a second position in which the outlet means is disconnected from the interior of the container and placed in communication with the rinsing fluid inlet means so that rinsing fluid flows through the outlet means, and control means for moving the valve member from the second to the first position, the control means comprising a piston connected to the valve member and movable in a cylinder forming part of the dispensing head, and second rinsing fluid inlet means adapted to be connected to the source of rinsing fluid and opening into the cylinder so that on supply of rinsing fluid to the second rinsing fluid inlet means the pressure of the rinsing fluid acting on the piston urges the valve member to its first position.

7. A dispensing head as claimed in claim 6, in which the first rinsing fluid inlet means is in communication with the cylinder so that when rinsing fluid is supplied to the first rinsing fluid inlet means whilst supply of rinsing fluid to the second rinsing fluid inlet means is cut off, the pressure of rinsing fluid supplied to the first rinsing fluid inlet means urges the valve member to its second position.

8. A dispensing head as claimed in claim 7, characterised in that the first rinsing fluid inlet means is, when the valve member is in its second position, connected to the outlet means through the cylinder.

9. A dispensing head as claimed in any one of claims 3 to 9, characterised in that the valve member has a longitudinal channel providing the outlet means, and a one-way valve is positioned in the channel to prevent rinsing fluid from entering the container to which the head is fitted.

10. An installation for dispensing liquid from a container, comprising a dispensing head adapted to be fitted to the container having a valve plunger with which the dispensing head co-operates to enable liquid in the container to be dispensed through the dispensing head under pressure of a gas supplied to the container through the dispensing head, a source of pressurising gas connected to gas inlet means of the dispensing head and a dispensing tap connected to outlet means of the dispensing head through a length of delivery pipe, rinsing fluid inlet means connected to a source of rinsing fluid and valve means in the dispensing head movable between a first position in which the rinsing fluid inlet means is closed, the gas inlet means is in communication with the interior of the container to which the dispensing head is fitted and the outlet means is in communication with the interior of the container through the valve plunger so that liquid is dispensed from the container through the dispensing tap, and a second position in which the outlet means is disconnected from the interior of the container and placed in communication with the rinsing fluid inlet means so that rinsing fluid flows through the outlet means, the delivery pipe and the dispensing tap, and in that the installation includes control means operable from a position close to the dispensing tap for controlling the position of the valve means independently of the supply of gas to the gas inlet means.

11. An installation as claimed in claim 10, characterised in that the valve means comprises a valve member vertically movable in a body of the dispensing head between a first position in which, in use, the valve member engages the valve plunger of the container and holds it in its open position and a second position in which the valve member is disengaged from the valve plunger, the valve member including a piston movable in a cylinder forming part of the body of the dispensing head, and in that a control inlet to the cylinder is connected to the source of pressurising gas through a control valve forming part of the control means so that when the control valve is open the pressure of the gas supplied to the cylinder through the control inlet urges the valve member to its first position.

12. An installation as claimed in claim 11, characterised in that the control valve is a manually operated valve positioned close to the dispensing tap.

13. An installation as claimed in claim 11, characterised in that the control valve is positioned in the region of the dispensing head and the source of pressurising gas, and in that auxiliary control means are provided for operating the control valve from a position close to the dispensing tap.

14. An installation as claimed in claim 13, characterised in that the auxiliary control means comprises a further control valve positioned close to the dispensing tap and connected in a branch line between the source of pressurising gas and the first control valve, the first control valve being operable by pressure of gas supplied to it through the further control valve.

15. An installation as claimed in claim 13, characterised in that the control valve is a solenoid-operated valve and the auxiliary control means comprises an electrical circuit for controlling operation of the valve, the electical circuit including an operating switch positioned close to the dispensing tap.

16. An installation as claimed in any one of claims 13 to 15, characterised in that the control valve is adapted to interrupt the supply of rinsing fluid to the further inlet of the dispensing head when pressurising gas is supplied to the control inlet to hold the valve member in its first position.

17. An installation as claimed in claim 10, characterised in that the valve means comprises a valve member vertically movable in a body of the dispensing head between a first position in which, in use, the valve member engages the valve plunger and holds it in its open position and a second position in which the valve member is disengaged from the valve plunger, the valve member including a piston movable in a cylinder forming part of the body of the dispensing head, and in that a control inlet to the cylinder is connected to the source of rinsing fluid through a control valve so that when the control valve is operated to effect supply of rinsing fluid to the control inlet the pressure of the fluid acts on the piston to move the valve member to its first position.

18. An installation as claimed in claim 17, characterised in that the source of rinsing fluid is connected to the further inlet through the said control valve, the control valve having a first position in which fluid is supplied to the control inlet whilst the fluid supply to the further inlet is cut off and a second position in which fluid is supplied to the further inlet whilst the fluid supply to the control inlet is cut off.

19. An installation as claimed in claim 18, characterised in that the further inlet opens into the cylinder on the side of the piston remote from the control inlet, the pair of the cylinder on the said side of the piston being in communication with the outlet means when the valve member is in its second position.

20. An installation as claimed in claim 19, characterised in that the control valve has a vent outlet which is connected to a drain, the further inlet being in communication with the vent outlet when the valve member is in its first position so that the part of the cylinder on the said side of the piston is relieved of pressure.

21.An installation as claimed in any one of claims 10 to 20, characterised in that the rinsing fluid is mains water.

22. An installation as claimed in any one of claims 10 to 20 and adapted for dispensing beer or lager from a keg, in which the pressurising gas is carbon dioxide.

23. A dispensing head constructed, arranged and adapted to operate substantially as described with reference to, and as shown in, Figures 1 to 3, or Figures 7 and 8, or Figures 9 and 10, or any of the aforesaid groups of Figures as modified by Figure 12 or by Figure 13.

24. An installation for dispensing liquid from a container, substantially as described with reference to, and as shown in, any one of Figures 4, 5, 6 and 11.