초록 ▼

An improved, hand actuatable pump assembly. A stem and piston assembly extend into a valve body. The piston sealingly engages the wall of the valve body and together they define a pressure chamber therebelow. The piston seals a discharge passageway in the stem. As the pump assembly is primed, air in

An improved, hand actuatable pump assembly. A stem and piston assembly extend into a valve body. The piston sealingly engages the wall of the valve body and together they define a pressure chamber therebelow. The piston seals a discharge passageway in the stem. As the pump assembly is primed, air in the pressure chamber escapes through the discharge passageway. When the pump is ready for use, the force of hydraulic pressure below the piston opens communication between the pressure chamber and passageway. When the piston nears the end of the stroke, it is mechanically held open to complete dispensing. At all times, a positive seal between the piston and the valve body wall is maintained to prevent passage of the contents of the pressure chamber therebetween, thereby to minimize sticking and clogging of the pump assembly.

대표청구항 ▼

A hand-actuatable pump assembly adapted to be sealingly secured to the mouth of a container for dispensing material in the container, comprising a spray member defining a discharge opening, an elongate stem means defining a discharge passageway communicating with said discharge opening, an elongated

A hand-actuatable pump assembly adapted to be sealingly secured to the mouth of a container for dispensing material in the container, comprising a spray member defining a discharge opening, an elongate stem means defining a discharge passageway communicating with said discharge opening, an elongated valve body defining an interior pressure chamber for containing material to be dispensed through said discharge opening, said stem means extending into said valve body and being reciprocably movable in said valve body from an upper position to lower dispensing positions, piston means secured to said stem means and being sealingly seated thereon to close off said passageway from said body interior in said upper position, said piston means being in sealing engagement with said valve body above said pressure chamber to prevent material in said pressure chamber from passing between said piston means and said valve body, abutment means in said pressure chamber and positioned to engage said piston means as said piston means is moved downwardly from said upper position to a lower dispensing position to hold open said passageway thereby to maintain communication between said passageway and said valve body pressure chamber while preventing passage of material between the piston and the valve body interior above the piston.