Abstract: A trigger sprayer pump for dispensing a fluid from a container includes a body containing a pumping chamber having an inlet and an outlet conduit. A piston is reciprocably mounted in the pumping chamber, the piston having a convexly contoured outer end surface. A trigger pivotally mounted and locked to the body has a plurality of triangular supports co-joined to form a tapered socket receiving the outer end surface of the piston. A channel-defining insert is received in the outlet conduit, the insert having a centrally situated, forwardly facing, fixed surface. The fixed surface can be concave or a convex protuberance. An elastic, cup-shaped member secured at its periphery to the body has a central aperture situated in contact with and closed by the fixed surface.

Abstract: A hand-operated pump for dispensing a fluid from a container includes a body containing a pumping chamber having an inlet and an outlet. A piston is reciprocably mounted in the pumping chamber, the piston having a convexly contoured outer end surface. A trigger pivotally mounted to the body has a plurality of triangular supports co-joined to form a tapered socket receiving the outer end surface of the piston. A channel-defining insert is received in the outlet, the insert having a centrally situated, forwardly facing, fixed protuberance. An elastic, cup-shaped member secured at its periphery to the body has a central aperture situated in contact with and closed by the fixed protuberance.

Abstract: A hand-operated pump for dispensing a fluid from a container includes a body containing a pumping chamber having an inlet and an outlet conduit. A piston is reciprocably mounted in the pumping chamber, the piston having a convexly contoured outer end surface. A trigger pivotally mounted and locked to the body has a plurality of triangular supports co-joined to form a tapered socket receiving the outer end surface of the piston. A channel-defining insert is received in the outlet conduit, the insert having a centrally situated, forwardly facing, fixed protuberance. An elastic, cup-shaped member secured at its periphery to the body has a central aperture situated in contact with and closed by the fixed protuberance.