An electric pump includes a motor unit rotationally driving a drive shaft, and a pump unit. The pump unit includes a pump rotor that sends the fluid by a driving force of the driving shaft, and a pump housing that covers at least one side of the pump rotor. The pump housing includes an attachment surface extending in the axial direction and in contact with an attached body, first and second flow paths respectively on the suction side and the discharge side, and a partition wall positioned between pump-side openings of the first flow path and the second flow path facing the pump rotor, and extends in a direction along the attachment surface, and locations of attachment-side openings of the first flow path and the second flow path on the attachment surface are displaced from each other on the attachment surface in the axial direction.

An assembly for adjustably mounting a gear of a pump to a gear of a driver equipment includes a shroud member, and a hollow elongated stub-shaft. The stub-shaft includes a flange, and a hub member axially extending from the flange. The shroud member defines a first aperture whose diameter is greater than a diameter of the hub member. The hub member is received within the shroud member via the first aperture. The flange has a first set of holes to receive a first set of fasteners and releasably couple with the body of the pump. The flange also has a second set of holes that are configured to receive a second set of fasteners and releasably couple with the shroud member. A diameter of the second set of holes is greater than a diameter of the second set of fasteners.

A fuel pump system for a turbomachine engine can include a boost pump driven by an electric motor and configured to be in fluid communication with a fuel tank, a primary pump configured to be driven by a shaft connected to the turbomachine engine, wherein the primary pump is in fluid communication with the boost pump downstream of the boost pump by a boost branch, a bypass flow branch that connects the boost branch to a downstream branch that is downstream of the primary pump, the downstream branch is in fluid communication with one or more metering valves and/or one or more fuel nozzles, and a bypass valve disposed in the bypass flow branch and/or the downstream branch and configured to selectively directly fluidly communicate the boost branch and the downstream branch.

A uniaxial eccentric screw pump for rotating a rotor about its axis and revolving the rotor without involving complicated operations and control is provided. The uniaxial eccentric screw pump includes a rotor drive mechanism capable of revolving a rotor while rotating the rotor about its axis. The rotor drive mechanism includes a rotation power transmission member rotatable about a predetermined center axis, and a revolution track formation member capable of revolving a proximal shaft portion of the rotor while allowing rotation of the proximal shaft portion about its axis. The rotor drive mechanism distributes power output from the same motor in parallel and transmit the power to the rotation power transmission member and the revolution track formation member, enabling the rotation power transmission member and the revolution track formation member to rotate about their axes while being synchronized mechanically, and enabling the rotor to revolve while rotating about its axis.

An electric submersible progressive cavity pump assembly is disclosed, which includes an electric motor, a progressive cavity pump, a transmission rotatable by the motor, and a torque isolator coupled between the transmission and the progressive cavity pump, where the torque isolator includes resilient members which accommodate sudden changes in torque.

A submersible pump assembly has a seal section between the motor and the well fluid pump, the seal section having a housing, a shaft and a thrust bearing unit. The thrust bearing unit includes a thrust runner mounted to the shaft that rotates against a thrust bearing base fixed in the housing. An annular, metal thrust runner wave spring has an inner diameter surface in contact with the shaft and an outer diameter surface in contact with the runner bore. The wave spring has a transverse width between the inner diameter surface and the outer diameter surface that is elastically deflectable, exerting an inward bias force against the shaft and an outward bias force against the runner bore.

A progressing cavity pump operated by a motor is provided. In one embodiment, a system includes a motor, a progressing cavity pump having a rotor and a stator, and a fluid coupling that connects the motor to the progressing cavity pump. The fluid coupling includes an input turbine and an output turbine disposed within a housing. The motor is connected to the input turbine of the fluid coupling and the rotor of the progressing cavity pump is connected to the output turbine of the fluid coupling to enable the progressing cavity pump to be operated by the motor via the fluid coupling to pump fluid through the progressing cavity pump. Additional systems, devices, and methods are also disclosed.

A downhole pumping apparatus comprising a positive displacement rotary gear pump (RGP), driven by a rotating rod string or a submersible electric motor.

A universal joint (U-joint) assembly transmits torque from a drive component to a driven component across an articulating joint. The U-joint assembly includes male and female U-joint members, a central ball joint, and a retaining device configured to secure the assembly in an assembled configuration. The female U-joint member includes a cavity extending into a receptacle end thereof. The cavity terminates in a circular receptacle and includes a plurality of rectangular channels extending radially outward from the cavity at equal intervals, each channel defined by three planar drive surfaces. The male U-joint member has a drive end with a plurality of corresponding rectangular extensions protruding from an outer periphery of the drive end, each extension including a plurality of axial angular surfaces. When assembled, each of the angular surfaces of the drive end opposes a corresponding one of the drive surfaces of the cavity. Other embodiments are also disclosed.

An oil pump includes a hollow rotor having an inner peripheral portion defining a space inside of the inner peripheral portion. A first one-way clutch configured to transmit the motive power input from an engine side, to the rotor only in one direction, and a second one-way clutch configured to transmit the motive power input from an electric motor side, to the rotor only in the one direction are arranged inside of the inner peripheral portion of the rotor.