| 摘要 |
A dispenser (10) for flowable, viscous material (52) is provided which includes a reservoir (50) for the material (52) with an elongated, synthetic resin deformable outlet tube (80) presenting an outlet end (82) coupled to the reservoir (50). A flow-controlling assembly (16) including a tube-engaging element (84, 132, 150, 158) and an actuator linkage assembly (86, 130, 144, 154) allows precise on-off operation of the dispenser (10). In the flow-permitting position, the element (84, 132, 150, 158) is adjacent the tube (80). When it is desired to terminate material flow, the actuator linkage assembly (86, 130, 144, 154) is operated to cause the element (84, 132,150, 158) to move into deforming engagement with the tube (80) against a backing surface (41); continued movement of the element (84, 132, 150, 158) along the length of the tube (80) in a direction away from outlet end (82) generates a suction force causing material (52) adjacent the end (82) to be drawn into the confines of the tube (80). This prevents air-drying of the material (52) at outlet end (82), ensuring continued smooth operation of the dispenser (10) while minimizing material loss. Preferably, the assembly (16) applies resilient flow-blocking force against the outlet tube (80). |
