The gear pump may have a casing, a main shaft and rotating means connected to one end of the main shaft and configured to rotate the main shaft. Housed by the casing, a toothed wheel and at least one other toothed element are intermeshed with the toothed wheel. The other end of the main shaft is connected to one of the toothed wheel and the casing. Rotating the main shaft relative to the rotating means rotates the toothed wheel and the at least one other toothed element relative to the casing, thereby generating the flow. The other one of the casing and the toothed wheel is configured to be rotated around an axis defined by the main shaft for varying a flow rate of the generated flow.

A pump stage assembly for supplying lubricating oil, comprising: at least two pump suction stages and at least one pump pressure stage. The pump suction stages and the pump pressure stage are spaced apart from one another in a pump housing PG and have a common drive shaft. The pump suction stages are formed by a first assembly of at least three intermeshing external gearwheels and wherein the pump pressure stage is formed by a second assembly of two intermeshing external gearwheels. Here at least two respective tooth center points of the first external gearwheel assembly and the respective tooth center points of the second external gearwheel assembly are arranged in a common plane E-E which intersects the pump housing PG in a longitudinal direction.

The gear pump may have a casing, a main shaft and rotating means connected to one end of the main shaft and configured to rotate the main shaft. Housed by the casing, a toothed wheel and at least one other toothed element are intermeshed with the toothed wheel. The other end of the main shaft is connected to one of the toothed wheel and the casing. Rotating the main shaft relative to the rotating means rotates the toothed wheel and the at least one other toothed element relative to the casing, thereby generating the flow. The other one of the casing and the toothed wheel is configured to be rotated around an axis defined by the main shaft for varying a flow rate of the generated flow.

A rotary positive displacement pump comprising a pair of forwardly-positioned sealing arrangements and a pair of forwardly-positioned sleeves are received within a cavity providing for easy maintenance of the pump when the seals need to serviced. Each of the sealing arrangement includes a dynamic seal and a static seal. The dynamic seal abuts a corresponding sleeve and hub while a static seal is established between the corresponding sleeve and rotor.

A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.

A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.

A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.

A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.

A linear actuator system includes a linear actuator and at least one integrated pump assembly connected to the linear actuator to provide fluid to operate the linear actuator. The integrated pump assembly includes a pump with at least one fluid driver comprising a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from a first port of the pump to a second port of the pump. The pump assembly also includes two valve assembles to isolate the pump from the system. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover to exclusively adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.

A linear actuator system includes a linear actuator and at least one integrated pump assembly connected to the linear actuator to provide fluid to operate the linear actuator. The integrated pump assembly includes a pump with at least one fluid driver comprising a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from a first port of the pump to a second port of the pump. The pump assembly also includes two valve assembles to isolate the pump from the system. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover to exclusively adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.