A variable reciprocating pump assembly including a driven crank wheel, a crank arm coupled to and driven by the crank wheel the crank arm terminating at a wrist pin, a pump housing, and a piston is disclosed. The assembly may be adjustable to provide varied stroke length and pump capacity without affecting performance or drive properties.

An inflating device includes a main body, an outer cylinder, an inner cylinder, a handle, an inflating tube and a switching structure. The outer cylinder is disposed within the main body and an upper portion of the outer cylinder defines a cavity which has a bottom surface defining a sliding passage. The inner cylinder is disposed within the outer cylinder. The switching structure includes a slide unit and a press cover. The slide unit is disposed slidably in left and right directions within a sliding passage. The press cover is mounted on the upper portion of the outer cylinder so as to cover the cavity and the slide unit. The inflating device can be conveniently switched between a small pump unit and a large pump unit by the switching structure.

An inflating device includes a main body, an outer cylinder, an inner cylinder, a handle, an inflating tube and a switching structure. The outer cylinder is disposed within the main body and an upper portion of the outer cylinder defines a cavity which has a bottom surface defining a sliding passage. The inner cylinder is disposed within the outer cylinder. The switching structure includes a slide unit and a press cover. The slide unit is disposed slidably in left and right directions within a sliding passage. The press cover is mounted on the upper portion of the outer cylinder so as to cover the cavity and the slide unit. The inflating device can be conveniently switched between a small pump unit and a large pump unit by the switching structure.

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.

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 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 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 liquid pumping device includes a liquid pumping tube module, an axial movement module, a rotation module and a translation module. The liquid pumping tube module includes a tube and an adapter. The tube has a first end and a second end in an axial direction. The adapter is disposed at the second end. The axial movement module is connected to the tube, and drives the liquid pumping tube module to move in the axial direction. The rotation module is connected to the liquid pumping tube module, and drives the liquid pumping tube module to rotate relative to a rotation axis of the rotation module. The translation module is connected to the liquid pumping tube module, and drives the liquid pumping tube module to move on a plane perpendicular to a plane of rotation of the rotation module.