| 摘要 |
A dispenser for dispensing a predetermined volume of liquid through a nozzle (18), has a liquid reservoir (32) of which the upper part (34) contains gas under pressure. The nozzle is connected to a valve spindle (16) and a tube (14) which pass up through the reservoir into a gas chamber (8). When the nozzle (18) is pushed upwards, the metered volume in the tube and spindle is expelled by the pressurised gas. Releasing of the nozzle enables liquid from the reservoir to pass through a port (20) into the spindle (16), and up the tube (14) to refill the metered volume; and on return to its normal rest position the port (20) is again out of communication with the reservoir (32), and any excess liquid in the chamber (8) flows through slots (36) back into the reservoir. |
