| 摘要 |
A dispensing nozzle for a liquid composition introduced through an inlet (20) has its discharge nozzle orifice (21) closable by the tip (3a) of a longitudinally movable needle valve member (3) (Figure 2) the point of entry of the needle valve member (3) into the dispensing chamber (1) being sealed by means of an elongate annular seal portion which extends and contracts in response to longitudinal movement of the needle valve member while simultaneously undergoing a change in external cross-section whereby the volume of the longitudinal portion (11) of the seal remains substantially unaltered and the shaft of the needle valve member (3) displaces longitudinally substantially without sliding relative to the seal portion (11). The internal wall of the longitudinal portion (11) of the seal is held clear of the needle valve member by a coil spring (23). <IMAGE> |
