DOSING PUMP FOR LIQUID DISPENSERS

摘要

A dispenser for dispensing metered amounts of a viscous liquid includes a liquid reservoir and a pump chamber having an opening in communication with the reservoir. A dispensing orifice is defined in the pump chamber. A pump mechanism is configured with the pump chamber and is movable from a rest to a pressurizing position upon actuation thereof to pressurize liquid within the pump chamber. A check valve mechanism is disposed in the opening. A restriction device is disposed in the dispensing orifice and maintains a closed configuration to prevent leakage of liquid from the dispensing orifice. The restriction device opens upon sufficient liquid pressure build-up within the pump chamber upon actuation of the pump mechanism. The restriction device also may vent the pump chamber upon release of the pump mechanism.