US Patent 7575134 Self-sealing nozzle for dispensing apparatus

A self-sealing nozzle for a liquid dispensing device having a valve and a discharge port, the discharge port including a plug that may be bulbous in shape, the plug being retained by a retainer at the end of the discharge passage leading to the port. An elastomeric seal has an annular inner surface that seals against the plug when liquid is not being dispensed by said valve, but expands and forms a passage around the plug when liquid is being dispensed by said valve.