A pumping system utilizes a linear actuator to move a shaft attached to two pistons within cylinders to pump a working fluid. A housing is designed with coolant passageways and one-way valves such that movement of the shaft also pumps coolant past cooling fins and over a motor. The shaft is formed of several sections joined by couplers which slide within a bore of the housing. The couplers have a non-round shape and the bore has a complimentary non-round cross section such that rotation of the shaft is prevented.

In certain examples, a printing system comprises: a depositing system to deposit printing fluid on a print medium; a reservoir; and a displacement pump to move printing fluid to the depositing system from the reservoir. The displacement pump comprises: a pump body defining a chamber, an inlet to fluidly connect the chamber to the reservoir, and an outlet to fluidly connect the chamber to the depositing system; and a displacement member movable relative to the pump body; the displacement member having an outer surface and comprising a cavity located in a portion of the outer surface disposed in the chamber. In use, the displacement member is movable to close the inlet and to force printing fluid in the chamber through the outlet to the depositing system.

A plunger pump, comprising: a liquid tank; a pump body including a liquid storage part, a suction passage configured to allow communication between the liquid storage part and the liquid tank and a discharge passage configured to discharge a liquid in the liquid storage part to outside; and a plunger reciprocally movably supported in the pump body so that a tip reaches the liquid storage part. The suction passage includes a first suction passage, the tip of the plunger being reciprocally slidably inserted into the first suction passage, and a second suction passage provided in parallel to the first suction passage, and a check valve configured to allow only a flow of the liquid from the liquid tank to the liquid storage space is disposed in the second suction passage.

A plunger pump, comprising: a liquid tank; a pump body including a liquid storage part, a suction passage configured to allow communication between the liquid storage part and the liquid tank and a discharge passage configured to discharge a liquid in the liquid storage part to outside; and a plunger reciprocally movably supported in the pump body so that a tip reaches the liquid storage part. The suction passage includes a first suction passage, the tip of the plunger being reciprocally slidably inserted into the first suction passage, and a second suction passage provided in parallel to the first suction passage, and a check valve configured to allow only a flow of the liquid from the liquid tank to the liquid storage space is disposed in the second suction passage.

Disclosed is a micropump for delivery of a fluid. The micropump comprises body comprising metering chamber for receiving fluid and groove, and nozzle attached to metering chamber for delivering fluid. A capillary delivers fluid into metering chamber, and piston operates to move axially inside metering chamber. Axial movement of first end of piston (namely, piston face) along path between second end and first end of metering chamber delivers fluid through nozzle. Moreover, groove radially surrounds piston and has common axis with piston. The groove comprises sealing ring operable to move inside groove based on axial movement of piston. The sealing ring is in contact with piston and body. The sealing ring is manufactured using a rubber composition comprising hydrogenated nitrile butadiene rubber (HNBR), and carbon black.

A seal packing assembly for a hydraulic pump includes a plurality of annular dynamic seals disposed within annular grooves circumferentially defined in the annular bore, a packing gland circumferentially housing a section of the plunger, and a plurality of seal manifolds distributed and defined within the packing gland, each seal manifold defining a port at one end exposed to the pumping fluid and further defining a clean lubrication fluid inlet proximate to a second end, the fluid inlet coupled to a lube pump via a check valve, where the clean lubrication fluid housed in the seal manifolds is maintained at a constant pressure. Each seal manifold includes a piston disposed within the seal manifold having a first end configured with a first surface area to interface with the pumping fluid and a second end configured with a second surface area to interface with the clean lubrication fluid, and a fluid port configured to provide fluid communication between the seal manifold and the annular grooves of the annular dynamic seals.

A seal packing assembly for a hydraulic pump includes a plurality of annular dynamic seals disposed within annular grooves circumferentially defined in the annular bore, a packing gland circumferentially housing a section of the plunger, and a plurality of seal manifolds distributed and defined within the packing gland, each seal manifold defining a port at one end exposed to the pumping fluid and further defining a clean lubrication fluid inlet proximate to a second end, the fluid inlet coupled to a lube pump via a check valve, where the clean lubrication fluid housed in the seal manifolds is maintained at a constant pressure. Each seal manifold includes a piston disposed within the seal manifold having a first end configured with a first surface area to interface with the pumping fluid and a second end configured with a second surface area to interface with the clean lubrication fluid, and a fluid port configured to provide fluid communication between the seal manifold and the annular grooves of the annular dynamic seals.

A lubrication system for a plunger/packing set of a fluid end has a lubricating fluid reservoir, a pump cooperative with the lubricating fluid reservoir so as to pump a lubricating fluid from the lubricating fluid reservoir toward the plunger/packing set, a primary pressure transducer cooperative with the pump so as to measure a pressure of the lubricating fluid exiting the fluid pump, a secondary pressure transducer cooperative with the fluid end so as to measure a pressure of the lubricating fluid exiting the plunger/packing set, and a controller connected to the second pressure transducer so as to obtain a representation of the pressure measured by the secondary pressure transducer.

A reciprocating compressor 1A includes a compression part 2 compressing, by a piston 6, gas sucked into a cylinder 4 through a suction valve 36, and discharging the compressed gas through a discharge valve 51, a piston drive part 3 supplying a force to the piston 6 to reciprocate the piston 6 via a piston rod 9 coupled to the piston 6, and a housing 17 accommodating the compression part 2 and forming a vacuum region around the compression part 2.

A multi-stage compressor for compressing a fluid, the compressor comprising two or more cylinders each having a compression chamber and a piston, so that a fluid in each of the compression chambers can be com-pressed by the associated piston; the cylinders being connected in series such that a fluid entering an inlet of the compressor can be compressed to a first pressure in the compression chamber of a first cylinder and, then, enter into the compression chamber of a second cylinder where the compressed fluid is compressed to a second higher pressure and, before the fluid exits from an outlet of the com-pressor; wherein each piston is driven by one and the same crankpin of the compressor. Furthermore, a method for compressing a fluid, and a system for comprising the multi-stage stage compressor are disclosed.