LIQUID DISPENSE HEAD

Abstract: A dispense head, for gas-pressure dispensing of liquid from a cask, has a centre member (5), which is depressed to open the cask closure valve, on which centre member is carried a sealing ring and seating ring valve assembly (14, 15, 22), to control admission of gas, the assembly including an axially movable flange seating ring (14) and a resilient loading and sealing ring (15) which maintains closure of the gas flow path so long as there is no axial movement of the centre member relatively to the seating ring.

Description: This invention relates to dispense heads which each comprise a connector unit for fitting to a closure valve of a cask or like container for liquid to be dispensed through the head by the pressure of gas admitted through the head. Such a gas-pressure dispense head, then called a connector unit, is disclosed in document GB-A-1239907; which describes a gas-pressure dispense head, for use with the closure valve of a beverage container which comprises a head body, adapted for ready and retentive connection with the valve body of a keg closure valve; a center member, axially movable in the head body and having internal passages for gas and beverages respectively, which passages terminate in concentric mouths separated by an annular wall for engaging and opening the closure valve when the center member is manually depressed axially downwardly; an annular resilient seal encircling the annular wall, for sealingly contacting the valve closure body; and, a gas valve assembly to control admission of gas through the head and constructed to be operative only when the head is connected to the closure valve body. The gas valve assembly was formed by a valve member carried by the annular resilient seal which, due to compressive deformation of the annular resilient seal moved to open the gas passage in the head and, due to relaxing of such compression, moved to close off the gas passage. The disadvantage of this dispense head is that upwards manual depression (such as by unauthorised tampering by the insertion of a tool into the mouth of the dispense head) of the annular sealing ring would cause the gas passage in the head to open, releasing full gas pressure to atmosphere and possibly injuring the person tampering with the dispense head. It is an object of the present invention to provide a gas-pressure dispense head wherein the gas valve assembly will only open when the dispense head is correctly fitted to the closure valve. According to the present invention, the gas valve assembly of a gas-pressure dispense head comprises a flange seating ring movable on the center member against a first, resiliently deformable, sealing ring acting between the centre member and the valve body and arranged to normally load the seating ring against a second sealing ring located on the annular wall; and the annular resilient seal is a separate resilient gasket fixed to the valve body in the mouth of the gas passage whereby, only when the head is connected to a closure valve body and the centre member axially downwardly depressed to open the closure valve, can the seating ring sealingly engage the gasket to sealingly load the gasket against the closure valve body; and, when the head is disconnected, axial upwards manual depression of the gasket cannot open the gas valve assembly. The above and other features of the present invention are illustrated, by way of example, in the Drawings, wherein:- Fig. 1 is an axial section of a gas-pressure dispense head, in accordance with the present invention; and, Fig. 2 is a part sectional elevation of the dispense head of Fig. 1, shown coupled to a closure valve. The dispense head shown comprises a tubular body 1 of which the mouth at the base is partly surrounded by a gapped flanged skirt 2 to slide laterally into engagement with a flange 3 on a closure valve body 4 (Fig. 2). The closure valve is of a standard poppet type and is not shown. In the bore of the body 1 a tubular centre member 5 forms the liquid-dispensing outlet, past a non-return valve 6, and is axially slidable under the control of a hand-lever 7 pivoted on a lug 8 on the body 1 and housing a spring-loaded latch 9 which engages over a keeper 10 and normally holds the lever in its raised position (Fig.1) but can be pulled up to pass the keeper and then released to engage below the keeper when the lever is to be lowered to open the head. Downward movement of the lever 7 slides the centre member 5 down through the flange 3 to open downwards the cask closure valve by thrust of the rim of the bell-shaped lower end 11 of the centre member 5. The body 1 has a gas inlet branch 12 to which a gas supply pipe (not shown) is connected and which opens to the bore of the body 1 by an inlet port 13. Controlling admission of gas through the port 13 is the valve assembly provided by the present invention and including essentially an axially movable flange seating ring 14 and a loading ring 15 of resiliently deformable material housed in an enlarged bore 16 in the lower end of the body 1. The loading ring 15 is held in an annular channel 17 in a flange 18 at the lower end of a sleeve 19 slidable on a cylindrical wall 20 of the centre member 5 and retained by a circlip 21. The seating ring 14 rests as a freely slidable flange on the enlarged, bell-shaped, inner end 11 of the centre member 5 with an interposed O-ring 22 and, in the closed condition of the dispense head, the circlip 21 holds the sleeve 19, loading ring 15, flange seating ring 14 and O-ring 22 axially stressed in compression. Above and below the gas inlet port 13, the bore of the body 1 is sealed respectively by an O-ring 23, against the wall 20, and an O-ring 24, against the sleeve 19. Gas-flow passages, formed by flutes 25, in the bore of the sleeve 19, and notches 26, in the inner rim of the ring 14, provide a path (indicated by arrows in Fig. 2) for gas from the port 13, past the lower end 11 of the centre member 5 and into the cask, to displace liquid, only when the centre member 5 has been moved down, by the lever 7, relatively to the seating ring 14 (Fig.2). Fig. 2 shows how the ring 14, loaded by the ring 15, is stopped by and seals against a resilient gasket 27, which in turn seals against the cask valve flange 3 to provide an atmospheric seal and prevent leakage of liquid. In use, the dispense head is fitted to the closure valve of a cask, a gas supply pipe is connected to the inlet branch 12 and a delivery pipe (not shown), connected to the upper end 28 of the centre member 5, leads to a service tap for the liquid to be dispensed. So long as the lever 7 is in its raised position the cask closure valve remains closed, the gas inlet port is closed by the sleeve 19 and the gas flow path is closed and sealed by the O-ring 22, the loading ring 15 and O-rings 23 and 24 preventing leakage of gas from the valve assembly. To set the dispense head in condition ready for liquid to be served from a tap fed through a pipe connected to the upper end 28 of the centre member 5, the latch 9 is pulled upward and the lever 7 turned down for the latch 9 to engage below the keeper 10. This lever movement thrusts the centre member 5 down to open the cask closure valve and open the gas inlet path past the O-ring 22 as the seating ring 14 is stopped by and seals against the gasket 27 held against the flange 3. When the lever 7 is raised, the centre member is lifted to allow the cask valve to close and to close off the gas flow path by the O-ring 22 against the seating ring 14. The shape of the flange seating ring 14 is an important feature of the invention. The lower side of the ring has inner and outer peripheral bevels 29 and 30 so that not only does the bevel 29 seal against the O-ring 22 but, in the open condition of the head, the bevel 30 stops and seals against the gasket 27. This ensures that the centre member moves through the seating ring 14, to open the gas flow path past the O-ring 22, only when the dispense head is correctly fitted to a closure valve flange 3 and gasket 27. When disconnected, gasket 27 also provides an anti-tamper seal as, to force the gas path open, an instrument would have to be introduced to pass gasket 27, lift ring 14 to compress ring 15 and prevent the centre member 5 from lifting with sleeve 19.

Claims: A gas-pressure dispense head, for use with the closure valve of a beverage container:- comprising a head body (1), adapted for ready and retentive connection with the valve body (3) of a keg closure valve (4); a center member (5), axially movable in the head body and having internal passages for gas (13) and beverage respectively, which passages terminate in concentric mouths separated by an annular wall (11) for engaging and opening the closure valve when the center member is manually depressed axially downwardly; an annular resilient seal (27) encircling the annular wall, for sealingly contacting the valve closure body; and a valve assembly (15,14,22) to control admission of gas through the head and constructed to be operative only when the head is connected to the closure valve body characterised in that:- the gas valve assembly comprises a flange seating ring (14) movable on the center member (5) against a first, resiliently deformable, sealing ring (15) acting between the center member and the valve body (1) and arranged to normally load the seating ring against a second sealing ring (22) located on the annular wall (11); and the annular resilient seal is a separate resilient gasket (27) fixed to the valve body in the mouth of the gas passage, whereby, only when the head is connected to a closure valve body and the center member axially downwardly depressed to open the closure valve, can the seating ring sealingly engage the gasket to sealingly load the gasket against the closure valve body; and, when the head is disconnected, axial, upwards manual depression of the gasket cannot open the gas valve assembly. A dispense head as claimed in claim 1 and further characterised in that the gas passage mouth, the gasket (27) and the mouth of the annular wall (11) are substantially coplanar when the head is disconnected. A dispense head as claimed in claim 1 or claim 2 and further characterised in that a sleeve (19), slideable on the center member (5), houses the first sealing ring (15); the annular wall (11) has a larger diameter than the center member; and, stop means (21) are provided on the center member to limit upwards axial movement of the sleeve relative to the center member. A dispense head as claimed in claim 3 and further characterised in that the sleeve (19) has flutes (25) and the seating ring (14) notches (26) to provide a gas flow path. A dispense head as claimed in claim 3 or claim 4 and further characterised in that the first sealing ring (15) is held in an annular channel (17) of a flange (18) at the lower end of the sleeve (19). A dispense head as claimed in claim 1 or claim 2 and further characterised in that the seating ring (14) causes the gasket (27) to yield when the center member (5) is axially depressed and the dispense head (1) is disconnected, so that the seating ring remains in sealed contact with the second sealing ring. A dispense head as claimed in claim 1 or claim 6 and further characterised in that the seating ring (14) has inner and outer bevels (29,30) respectively to seal against the gasket (27) and the second sealing ring (22); to control the gas flow path. A dispense head as claimed in claim 6 or claim 7 and further characterised in that the gasket (27) seals against the annular wall (11) when the dispense head (1) is disconnected.

Inventors: HYDE, ROGER JOHN
Applicants: ROYAL PACKAGING INDUSTRIES VAN LEER B.V.
Application year: 1987
Main classification: B67D1
IPC codes: B67D1