A water pump assembly includes a lower housing configured for being positioned within a well. The lower housing includes a bladder therein. The bladder expands to force water within the housing into an outlet of a valve apparatus and the bladder contracts to draw water into the housing. A cylinder and piston fluidly coupled to an inlet of the valve apparatus and the inlet is fluidly coupled to the bladder. A one way valve is positioned within the valve apparatus and fluidly connects an inlet chamber including the inlet to an outlet chamber including the outlet. The one way valve allows water to flow from the outlet chamber into the inlet chamber and restricts water from flowing from the inlet chamber into the outlet chamber. An outlet conduit is fluidly coupled to the outlet of the valve apparatus to carry the water where desired.

A scroll compressor includes a shell that is cylindrical, a fixed scroll fixed to an inner wall of the shell, an orbiting scroll that faces the fixed scroll, a frame fixed to the inner wall of the shell and that supports the orbiting scroll, and a heat source device provided on an outside of the shell and between the fixed scroll and the frame and configured to heat or cool the shell from the outside.

The purpose of the present invention is to provide a scroll-type fluid machine for which maintenance can easily be performed in necessary locations, and a maintenance method for said fluid machine. The present invention provides a scroll-type fluid machined characterized by being provided with a main body unit for compressing a fluid, and a motor unit for driving the main body unit; the main body unit having a fixed scroll, a revolving scroll, a main body casing, and an autorotation-preventing mechanism that is held by the revolving scroll and the main body casing and that prevents autorotation of the revolving scroll; the motor unit having a rotor, a stator for causing the rotor to rotate, a shaft that rotates integrally with the rotor, a motor cover for housing the rotor and the stator, and a main bearing that is secured to the interior by the motor cover and that supports the shaft; a distal end of the shaft having an eccentric part; the main body unit and the motor unit being connected via the eccentric part; and the main body casing and the motor cover being fastened by a fastening member.

A gerotor pump having an inner rotor and an outer rotor, which is also the rotor of an electric drive, having a housing and a flange which closes the housing with the motor compartment, the rotor being arranged on a shaft and sealing against the flange at a gap, wherein, in addition to the gap, there is at least one device with which at least a partial pressure compensation takes place between the suction region of the gerotor pump and the motor compartment of the gerotor pump.

A hydrostatic transmission system includes a hydraulic motor and at least one proportional control valve and at least one pump connected to the hydraulic motor to provide fluid to operate the hydraulic motor. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The hydrostatic transmission system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of a flow and a pressure in the hydrostatic transmission system to an operational set point.

The present invention comprises: a stator 2 that is cylindrical and has a through hole 10, the through hole 10 in the shape of a female screw and being formed at a certain pitch in the flow direction from an inlet to an outlet; and a rotor 3 that is formed in the shape of a male screw, is inserted into the through hole 10 of the stator 2 to form a transport space 11 with the inner circumferential surface of the through hole, and rotates to move a fluid from the inlet to the outlet through the transport space 11 while being inscribed on the inner circumferential surface. The volume of the transport space 11 is reduced toward the flow direction. This prevents, reliably, the occurrence of bubbles from a fluid at a downstream-side when the fluid is transported through the transport space 11 formed between the stator 2 and the rotor 3.

A transfer pump configured to move a hydraulic fluid in a hydraulic fluid management system of a hydraulic system of a vehicle including a transmission. In one embodiment, the transfer pump moves the fluid from a differential case to a hydraulic reservoir coupled to the transmission. The transfer pump is a positive displacement pump including an unloading device, such as a sealing plate, that is resiliently biased against the pump during a normal operation but is moved away from the pump upon the application of a pilot pressure. The result is an open chamber for the pump gears to turn without developing pressure, to thereby reduce parasitic losses.

A balance shaft module includes a balance shaft for receiving a driving force from a crankshaft of an engine by a driving gear and rotating inside a balance shaft housing, an oil pump gear being geared with the driving gear to rotate along with the driving gear, an oil pump shaft having the oil pump gear press-fitted therein and rotating as the oil pump gear rotates, and an oil pump assembly mounted in the oil pump shaft and pumping oil as the oil pump shaft rotates, wherein a pair of support rings is provided at both side surfaces of the oil pump gear to support both side portions of the oil pump gear in the oil pump shaft.

A sectional sealing system for water-spray type screw rotor compressor that is configured to prevent the intermixing of coolant and working fluid from a compression chamber with lubricant used to lubricate at least a bearing system of a rotor. The sealing system may include suction side and discharge side sealing portions that are positioned about first and second shafts, respectively, of the rotor. The suction side sealing portion may include a first seal, a first labyrinth seal, and a second labyrinth seal, the first seal being in proximity to a suction side of the compression chamber. The discharge side sealing portion may include a plurality of first seals, a second seal, a first labyrinth seal, and a second labyrinth seal, the plurality of first seals of the discharge side sealing portion being in proximity to a discharge side of the compression chamber.

A screw spindle pump, including a housing and a drive spindle accommodated therein and at least one running spindle which meshes with the latter and which has in each case two terminal end surfaces. A stop surface is provided axially adjacent to at least one end surface of the running spindle, wherein the running spindle is accommodated displaceably with an axial clearance perpendicular to the stop surfaces.