Abstract: A reservoir pump in which liquid supplied from a container in which the pump is installed enters a pressure chamber with respect to which a piston reciprocates in suction and compression strokes. The chamber communicates with a reservoir, (the supply) so that liquid is supplied into the chamber in the suction stroke of the piston and transferred under pressure into the reservoir during the compression stroke. The chamber is open to supply and to the reservoir via one-way valves which open during the suction and compression strokes, respectively. A passage providing an orifice with a cross section much smaller than the cross section of the opening into the chamber, which communicates the chamber with the supply, is open via another one-way valve during the suction stroke. Air enters through the passageway. This air is compressed during the compression stroke.

Abstract: A reservoir pump in which liquid supplied from a container in which the pump is installed enters a pressure chamber with respect to which a piston reciprocates in suction and compression strokes. The chamber communicates with a reservoir, (the supply) so that liquid is supplied into the chamber in the suction stroke of the piston and transferred under pressure into the reservoir during the compression stroke. The chamber is open to supply and to the reservoir via one-way valves which open during the suction and compression strokes, respectively. A passage providing an orifice with a cross section much smaller than the cross section of the opening into the chamber, which communicates the chamber with the supply, is open via another one-way valve during the suction stroke. Air enters through the passageway. This air is compressed during the compression stroke.

Abstract: A reservoir pump assembly for use with a container having a fill opening and an interior includes an annular, elongate reservoir casing configured for being inserted into the fill opening of the container and for being disposed substantially entirely within the interior of the container. The reservoir casing defines a pressure chamber configured for containing fluid under pressure. An annular, elongate guide cylinder is disposed substantially entirely within the pressure chamber and defines an inlet orifice and an outlet orifice. The outlet orifice interconnects the guide cylinder and the pressure chamber. The inlet orifice interconnects the guide cylinder and the interior of the container. An inlet valve is associated with the inlet orifice, and an outlet valve is associated with the outlet orifice. An elongate pump rod is disposed partially within the guide cylinder and is configured for reciprocating movement therein. The pump rod has a first end and a second end.