A liquid supply device which supplies liquid to a target object, comprises a cylinder having both ends closed; a piston which comparts an inner space of the cylinder into a first space and a second space, and is relatively slidable on an inner wall surface of the cylinder; a piston rod which extends to penetrate an end portion of the cylinder and has a tip end portion connected to the piston; a frame member to which a portion of the piston rod which is located outside the cylinder is fastened; a drive section which causes the cylinder to reciprocate in a direction in which the piston rod extends; a first flow line which is in communication with the first space to flow the liquid therethrough; and a second flow line which is in communication with the second space to flow the liquid therethrough.

A reciprocating injection pump is disclosed including but not limited to a reciprocating block driven by a rotating gear, the gear having a substantially circular shape with four gear teeth formed on the rotating gear along approximately one fourth of the substantially circular shape, the rotating gear is attached to a rotating motor, the rotating motor having a right-angle motor shaft.

Disclosed is a piston pump for a brake system installed in a bore of a modulator block communicating with an inlet port and a discharge port, wherein the piston pump includes: a cylinder unit provided to reciprocate within the bore; a piston unit having one end fixed and the other end dividing the inside of the cylinder unit into a first chamber and a second chamber and configured to expand or reduce the internal spaces of the first chamber and the second chamber by reciprocating movement of the cylinder unit; a first inlet valve installed in the cylinder unit to open and close an one-way flow of fluid from the inlet port to the first chamber; a second inlet valve installed in the cylinder unit to open and close an one-way flow of fluid from the inlet port to the second chamber; and an outlet valve to open and close an one-way flow of fluid from the first chamber or the second chamber to the discharge port.

An injector generator for use in geomechanical pumped storage systems includes a power end and a fluid end. The fluid end has one or more fluid chambers each having a fluid inlet and outlet that are controlled by rotary valves. The fluid end can function as a pump or as a motor driven by fluid pressure from the geomechanical storage formation.

A reciprocating compressor may include a shell, a first cylinder, a plate, a second cylinder, and a piston. The first cylinder may be disposed within the shell and may include a first valve. The plate may be fixed relative to the first cylinder and may include a second valve. The second cylinder may be axially aligned with the first cylinder and may be moveable relative to the first cylinder between first and second positions. The piston may be disposed within the second cylinder and may include a third valve. The piston may reciprocate relative to the first and second cylinders. The piston and the plate may define a first compression chamber therebetween. The piston and the first cylinder may define a second compression chamber therebetween. A fluid-injection passage extending through the first cylinder selectively provides a working fluid from a source to the second compression chamber.

A variable displacement fuel pump includes a pump body, a barrel disposed within the pump body, at least one piston disposed in the barrel, wherein the at least one piston is configured to reciprocate within the barrel, and an electronic control actuator operatively coupled to the barrel, wherein the control actuator rotates the barrel to a selected barrel angle relative to the at least one piston in response to a desired fuel flow.

Metering systems and methods are disclosed. A metering system is part of a larger fluidics sub-system that includes a flexible reservoir for storing insulin and a cannula assembly for delivering the insulin into sub-cutaneous tissue. The metering system draws a small dose of fluid from the reservoir and then pushes it down the cannula line and into the patient. The fluid dose is small relative to the reservoir volume, such that many pump strokes are required to completely empty the reservoir.

A two-component pumping system includes a first pump for pumping a first component, a second pump for pumping a second component, a motor, and a yoke assembly for connecting the motor to the first pump and the second pump and driving them simultaneously. The first pump includes a first displacement rod that reciprocates in a first pump axis. The second pump includes a second displacement rod that reciprocates in a second pump axis parallel to the first pump axis. The motor includes a drive shaft configured to reciprocate in a drive axis that is parallel to and in a common plane with the first and second pump axes. The motor is also configured to drive the first and second displacement rods in unison. The yoke assembly includes a top connector and a shoe. The top connector connects to the drive shaft.

A rotary pump for a fluid metering system is provided. The rotary pump reciprocates, and is reversed by a signal from a limit switch that is deflected by an actuator arm on a rotating sleeve of the pump system. The sleeve receives a gasket that forms a seal between the sleeve and the housing, the gasket having an opening surrounding a side hole of the sleeve to permit fluid to pass through the side hole between a pump volume and an inlet port or outlet port of the housing.

A rotary pump for a fluid metering system is provided. The rotary pump reciprocates, and is reversed by a signal from a limit switch that is deflected by an actuator arm on a rotating sleeve of the pump system.