摘要 |
In a hand-operated container- mounted piston pump, e.g. for cosmetics, the piston 5 and cylinder 8 have cooperating ports 16, 18, A, E to function as a slide valve controlling intake and delivery of liquid and air, there being no communication between the pump inlet and outlet in the rest position of the pump. The piston may be reciprocable and the cylinder fixed, or vice versa. Actuation may be by press button or trigger. <IMAGE> |