US 12,404,847 B2
Reciprocating piston pump
Kai P. Schubart, Oshkosh, WI (US); Christopher J. Rukas, Oshkosh, WI (US); Patrick S. Dillman, Hartford, WI (US); Erik S. Ellifson, Oshkosh, WI (US); and Aaron J. Rositch, Oshkosh, WI (US)
Assigned to OSHKOSH CORPORATION, Oshkosh, WI (US)
Filed by Oshkosh Corporation, Oshkosh, WI (US)
Filed on Oct. 23, 2023, as Appl. No. 18/382,875.
Application 18/382,875 is a continuation of application No. 17/961,182, filed on Oct. 6, 2022, granted, now 11,815,078.
Application 17/961,182 is a continuation of application No. 16/575,590, filed on Sep. 19, 2019, granted, now 11,480,165.
Prior Publication US 2024/0052818 A1, Feb. 15, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. F04B 27/067 (2006.01); F04B 27/00 (2006.01); F15B 15/14 (2006.01)
CPC F04B 27/0673 (2013.01) [F15B 15/1447 (2013.01); F04B 27/005 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A pump system comprising:
a housing defining a first internal volume and a second internal volume;
a first piston positioned to separate the first internal volume into a first chamber and a second chamber;
a second piston positioned to separate the second internal volume into a third chamber and a fourth chamber;
a first inlet check valve configured to be at least fluidly coupled to a gas spring, the first inlet check valve positioned to permit a first fluid received from the gas spring to enter the first chamber;
a second inlet check valve configured to be at least fluidly coupled to the gas spring, the first inlet check valve positioned to permit the first fluid received from the gas spring to enter the third chamber;
a directional control valve (DCV) repositionable between (a) a first position where the DCV is configured to fluidly couple the second chamber to a second fluid from a high pressure fluid source and (b) a second position where the DCV is configured to fluidly couple the fourth chamber to the second fluid from the high pressure fluid source; and
a relief valve configured to supply the second fluid to the DCV through an orifice to move the DCV from the first position to the second position, wherein the orifice is separate from the relief valve and positioned to resist flow of the second fluid to the relief valve.