Abstract: An anti-clog pump sprayer has a cover mounted for independent reciprocation on a plunger head, the cover having a cupped spring biased portion covering the discharge orifice on the head to avoid clogging on product drying, and being lifted off the orifice during the relative shift for uncovering the orifice in readiness for spraying. The sprayer may also have a product retraction device on the plunger head in communication with the discharge orifice, a projection on the underside of the cover top wall for actuating the device at the commencement of the plunger return stroke for creating a slight sub-atmospheric pressure for suctioning any residual product inwardly of the orifice to thereby avoid clogging.

Abstract: An anti-clog pump sprayer has a cover mounted for independent reciprocation on a plunger head, the cover having a cupped spring biased portion covering the discharge orifice on the head to avoid clogging on product drying, and being lifted off the orifice during the relative shift for uncovering the orifice in readiness for spraying. The sprayer may also have a product retraction device on the plunger head in communication with the discharge orifice, a projection on the underside of the cover top wall for actuating the device at the commencement of the plunger return stroke for creating a slight sub-atmospheric pressure for suctioning any residual product inwardly of the orifice to thereby avoid clogging.

Abstract: 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.

Abstract: A pre-compression pump sprayer has a spring biased discharge poppet valve element with a seal in engagement with the wall of the piston stem, a seal interruption to establish a discharge valve open position, and an upstream directed throttle valve presenting a two-stage pressure build-up discharge valve establishing a predetermined pressure threshold which when exceeded by fluid pressure generated in the pump chamber during pumping immediately opens the throttle valve and abruptly releases the fluid pressure at the valve open position. The valve has an elongated probe extending into the pump chamber of an extent as to shift the poppet valve open upon engaging the inlet check valve upon a full downstroke of the piston for evacuating air from the pump chamber out through the discharge orifice to effect pump priming.

Abstract: A fluid dispenser for simultaneously dispensing disparate fluids separately stored in separate fluid compartments of a container includes a single pump cylinder defining together with a dual seal piston a pair of in-line pump chambers for separately and simultaneously pumping the disparate fluids along separate discharge paths.