초록 ▼

A manually actuated pump dispenser has a water seal for maintaining the container vent ports sealed closed during pumping until at or near the end of the pressure stroke whereupon a vent path through which only air is permitted travel into the container, is open as the path is shielded against water

A manually actuated pump dispenser has a water seal for maintaining the container vent ports sealed closed during pumping until at or near the end of the pressure stroke whereupon a vent path through which only air is permitted travel into the container, is open as the path is shielded against water entering the vent path when pumping in a wet environment as when dispensing hair shampoo or hair conditioner. In a plunger lock-down position of shipping and storage, leakage of product through the vent ports is substantially avoided during a superatmospheric condition within the container.

대표청구항 ▼

[ What is claimed is:] [1.] A manually operated liquid dispensing pump adapted to be mounted on a container of liquid to be dispensed, including a piston having a stem extending through a pump collar, the piston being reciprocable within a pump cylinder during a pumping operation to therewith define

[ What is claimed is:] [1.] A manually operated liquid dispensing pump adapted to be mounted on a container of liquid to be dispensed, including a piston having a stem extending through a pump collar, the piston being reciprocable within a pump cylinder during a pumping operation to therewith define a variable volume pump chamber, said cylinder having a container vent port selectively venting the liquid in the container, said piston having a vent control means and a discharge valve for controlling a discharge of liquid from said chamber, a plunger head mounted on said stem having a discharge opening in communication with said valve, said head having a depending skirt surrounding an upper portion of said stem in spaced relation therewith, another portion of said stem being directly exposed to the atmosphere, the improvement wherein the pump includes liquid seal means mounted on said cylinder for sealing the vent port closed during the pumping operation to avoid ingress of a foreign liquid into the container via the vent port when using the pump in a wet environment, said seal means including an annular lip seal in sliding sealing engagement with said another portion of said stem; means on said upper portion of said stem substantially beneath said plunger head skirt for interrupting the sealing engagement at or near an end of each piston compression stroke to create vent passage means for opening the vent port, said interrupting means being maintained substantially moisture-free by said skirt when using the pump in the wet environment to avoid the ingress of said foreign liquid into the container in an open condition of the vent port.