A compressor includes a shell, first and second scroll members, a fitting assembly and a valve assembly. The first scroll member includes a first end plate having a first spiral wrap extending therefrom. The second scroll member includes a second end plate having a second spiral wrap extending therefrom and an injection passage formed in the second end plate. The second spiral wrap is meshingly engaged with the first spiral wrap to form compression pockets. The injection passage is in fluid communication with the compression pockets. The fitting assembly is in fluid communication with the injection passage. The valve assembly coupled to one of the second scroll member and the fitting assembly and movable between a closed position in which fluid communication between the compression pockets and the suction chamber is prevented and an open position in which fluid communication between the compression pockets and the suction chamber is allowed.

Systems and methods for a compressor system are provided for selectively operating the compressor system with reduced power consumption. An output demand level of the compressor system can be monitored over time to identify a demand profile. A pressure setpoint for the compressor system can be selectively adjusted based on the demand profile, including to selectively transition between an operational pressure setpoint for an active demand profile and a reduced pressure setpoint for an inactive demand profile.

Systems and methods for a compressor system are provided for selectively operating the compressor system with reduced power consumption. An output demand level of the compressor system can be monitored over time to identify a demand profile. A pressure setpoint for the compressor system can be selectively adjusted based on the demand profile, including to selectively transition between an operational pressure setpoint for an active demand profile and a reduced pressure setpoint for an inactive demand profile.

A vane pump (101) for an automatic transmission includes a suction-side behind-vane pressure duct (112) and a pressure-side behind-vane pressure duct (111). The suction-side behind-vane pressure duct (112) is connected to the pressure side (116) of the vane pump (1). A valve device (113, 114) is connected to the pressure-side behind-vane pressure duct (111). During operation of the vane pump (101), a pressure-side behind-vane pressure (p DH) can be set in the pressure-side behind-vane pressure duct (111) with the valve device (113, 114).

A vane pump (101) for an automatic transmission includes a suction-side behind-vane pressure duct (112) and a pressure-side behind-vane pressure duct (111). The suction-side behind-vane pressure duct (112) is connected to the pressure side (116) of the vane pump (1). A valve device (113, 114) is connected to the pressure-side behind-vane pressure duct (111). During operation of the vane pump (101), a pressure-side behind-vane pressure (p DH) can be set in the pressure-side behind-vane pressure duct (111) with the valve device (113, 114).

A pendulum pump includes a housing, a cover positioned on the housing and forming a cavity therebetween, an inner rotor and an outer rotor positioned within the cavity, wherein the inner rotor is connected via a plurality of pendulums to the outer rotor, and the pendulums are mounted to the outer rotor in an articulated manner such that a rotational eccentricity can be imparted between the inner rotor and the outer rotor to control a flow rate of the pendulum pump, and a protective plate positioned within the cavity and against a surface of one of the housing and the cover.

One example of a gerotor pump includes an inner rotor comprising multiple teeth, the inner rotor configured to rotate about a first longitudinal gerotor pump axis. The gerotor pump also includes a hollow outer rotor including an outer surface and an inner surface having substantially identical contours, the inner surface configured to engage with the multiple teeth and to rotate about a second longitudinal gerotor pump axis. The pump includes a pump housing within which the inner rotor and the outer rotor are disposed, wherein the outer surface of the outer rotor defines gaps between the pump housing and the outer rotor.

A fluid system includes a variable-speed and/or a variable-torque pump to pump a fluid, at least one proportional control valve assembly, an actuator that is operated by the fluid to control a load, and a controller that establishes a speed and/or torque of the pump and a position of the at least one proportional control valve assembly. The pump includes at least one fluid driver that provides fluid to the actuator, which can be, e.g., a fluid-actuated cylinder, a fluid-driven motor or another type of fluid-driven actuator that controls a load. Each fluid driver includes a prime mover and a fluid displacement assembly. The fluid displacement assembly can be driven by the prime mover such that fluid is transferred from the inlet port to the outlet port of the pump.

A fluid system includes a variable-speed and/or a variable-torque pump to pump a fluid, at least one proportional control valve assembly, an actuator that is operated by the fluid to control a load, and a controller that establishes a speed and/or torque of the pump and a position of the at least one proportional control valve assembly. The pump includes at least one fluid driver that provides fluid to the actuator, which can be, e.g., a fluid-actuated cylinder, a fluid-driven motor or another type of fluid-driven actuator that controls a load. Each fluid driver includes a prime mover and a fluid displacement assembly. The fluid displacement assembly can be driven by the prime mover such that fluid is transferred from the inlet port to the outlet port of the pump.

A variable displacement pump device includes a pump, a mover, a biasing member, first and second control chambers, and a controller. The first and second control chambers are provided between an inner periphery of a containing chamber of a housing and an outer periphery of the mover. Hydraulic oil is introduced from a discharge port into the first control chamber. The pump is configured to permit oil to be introduced from the discharge port into the second control chamber via a supply/discharge passage or to be discharged from inside the second control chamber. The second control chamber is located adjacent to any of the pump chambers in a discharge region or the discharge port via the mover. The controller is configured to switch states in which the second control chamber is opened and closed to the supply/discharge passage.