Patent ID: 8104646

Claim:
A manually operated trigger sprayer comprising: a sprayer housing having a liquid supply opening and a liquid discharge opening, a pump chamber in the sprayer housing, the pump chamber having an interior and a liquid inlet opening communicating with the pump chamber interior and a liquid outlet opening communicating with the pump chamber interior; a liquid supply passage extending through the sprayer housing from the liquid supply opening to the pump chamber liquid inlet opening, and a liquid discharge passage extending through the sprayer housing from the pump chamber liquid outlet opening to the liquid discharge opening; a pump piston mounted in the pump chamber defining an enclosed interior volume of the pump chamber, the pump piston being mounted for reciprocating movements between charge and discharge positions of the pump piston in the pump chamber where the interior volume of the pump chamber is increased and a vacuum is created in the pump chamber in response to the pump piston moving to the charge position and the interior volume of the pump chamber is decreased and a fluid pressure is created in the pump chamber in response to the pump piston moving to the discharge position; and a single unitary valve member inside the pump chamber interior volume, the valve member having an inlet valve element and an outlet valve element, the inlet valve element being positioned between the pump chamber liquid inlet opening and the pump piston and the outlet valve element being positioned between the pump chamber liquid outlet opening and the pump piston, the inlet valve element and the outlet valve element being resiliently flexible, whereby the inlet valve element flexes away from the liquid inlet opening and opens fluid communication between the liquid supply passage and the pump chamber interior volume and the outlet valve element extends over the liquid outlet opening and closes fluid communication between the pump chamber interior volume and the liquid discharge passage in response to the pump piston moving to the charge position, and the inlet valve element extends over the liquid inlet opening and closes fluid communication between the pump chamber interior volume and the liquid supply passage and the outlet valve element flexes away from the liquid outlet opening and opens fluid communication between the pump chamber interior volume and the liquid discharge passage in response to the pump piston moving to the discharge position, wherein the inlet valve seat surface extends around the outlet valve seat surface.