A variable displacement vane pump with electronic oil pressure control provides efficient pumping of engine oil precise regulation of engine oil pressure. The variable displacement oil pump includes a rotor supported in a housing for rotation about an axis of rotation and a slide ring movably supported in the housing. A plurality of vanes extends between the rotor and the slide ring to define a plurality of variable displacement pumping chambers. An electronic drive mechanism is configured to position the slide ring with respect to the axis of rotation, and a controller is configured to drive the electronic drive mechanism for selectively positioning the slide ring to adjust an eccentricity of the slide ring relative to the axis of rotation such that the displacement of the pumping chambers is varied.

In a variable displacement oil pump, a drain chamber 36 partitioned with respect to first and second control oil chambers 31, 32 and which serves to generate a biasing force in a concentric direction based on a pump drain pressure directly introduced from a drain port 22a is interposed between first control oil chamber 31 which serves to generate a biasing force in the concentric direction in which a volume variation quantity of a plurality of pump chambers PR for a cam ring 15 based on a control pressure as a main gallery pressure introduced from an internal combustion engine and second control oil chamber 32 which serves to generate the biasing force in an eccentric direction in which the volume variation quantity of the plurality of pump chambers PR is increased for cam ring 15 based on the control pressure.

This drive system for a motor vehicle includes a top end and a bottom end that are coupled together, a kinematic drive chain, a compressor, a main lubrication system, that includes a main circuit and a main pump, which supplies at least the bottom end with a main lubricant via the main circuit, and a secondary lubrication system, that includes at least one secondary circuit separated from the main circuit and at least one secondary pump separate from the main pump, the secondary pump supplying the top end and/or the compressor with a secondary lubricant via the secondary circuit. The secondary lubrication system includes at least one secondary actuator mechanically separate from the kinematic drive chain and that drives the secondary pump to supply the top end and/or the compressor with the secondary lubricant.

A valve device for a hydraulic circuit includes an actuator unit and a valve unit. The actuator unit comprises an electromagnetic circuit comprising an armature which moves in a translational manner, a core, a coil carrier, a coil configured to be energized, and a flux guiding device. The coil is arranged on the coil carrier. The valve unit comprises a valve housing comprising a transverse bore which serves as a first control chamber pressure port, a regulating slide mounted in the valve housing, the regulating slide being configured to move axially, a first outlet port, an inlet port, and a second control chamber pressure port arranged between the inlet port and the first outlet port.

A hydraulic system for a work vehicle has a high pressure circuit for providing high pressure hydraulic fluid, a medium pressure circuit for providing medium pressure hydraulic fluid, and a low pressure hydraulic circuit for providing low pressure hydraulic fluid. The high pressure circuit has a variable displacement charge pump that provides pressurized hydraulic fluid only to a high pressure variable displacement pump according to demand, which provides the further pressurized hydraulic fluid to a priority valve according to demand. The medium pressure circuit has a medium pressure variable displacement pump that provides pressurized hydraulic fluid according to demand. The low pressure circuit has at least one low pressure variable displacement pump that provides pressurized hydraulic fluid by way of an oil cooler and/or an oil cooler bypass controlled by a proportional valve.

An oil supply device includes an oil pump and an oil control valve. The oil control valve is connected to a control oil chamber of the oil pump via a control oil passage that includes an oil descent passage and an oil rise passage. One end of the oil descent passage on the control oil chamber side is disposed at a position closer to a bottom of the vehicle than the other end on the oil control valve side. The oil rise passage is disposed at a position closer to the control oil chamber side than the oil descent passage. One end of the oil rise passage on the control oil chamber side is disposed at a position closer to a top of the vehicle than the other end on the oil control valve side.

A variable displacement vane pump with electronic oil pressure control provides efficient pumping of engine oil precise regulation of engine oil pressure. The variable displacement oil pump includes a rotor supported in a housing for rotation about an axis of rotation and a slide ring movably supported in the housing. A plurality of vanes extends between the rotor and the slide ring to define a plurality of variable displacement pumping chambers. An electronic drive mechanism is configured to position the slide ring with respect to the axis of rotation, and a controller is configured to drive the electronic drive mechanism for selectively positioning the slide ring to adjust an eccentricity of the slide ring relative to the axis of rotation such that the displacement of the pumping chambers is varied.

A variable displacement oil pump includes: a pump constituting section; a movable member; an urging mechanism; a control hydraulic chamber group; a drain mechanism arranged to discharge the oil from a specific one control hydraulic chamber of the control hydraulic chamber group; and a control valve which into which the oil of an upstream side that is discharged from the discharge portion, or the oil from the control hydraulic chamber is introduced as a control hydraulic pressure, which is arranged to supply the oil of the upstream side that is discharged from the discharge portion to the specific one control hydraulic chamber, or to discharge the oil from the specific one control hydraulic chamber by the drain mechanism to regulate the pressure of the specific one control hydraulic chamber.

A variable displacement vane pump has a pressure controlled valve moveable between first and at least second valve positions based on an output pressure of the pressurized lubricant delivered through the outlet. The pressure controlled valve provides an integrated fail safe function to the pump when an electrical valve fails. The pressure controlled valve is inactive in the first position for an output pressure below a threshold level, allowing an electrical valve (current, solenoid, pulse width modulation (PWM) valve) to selectively control pressure in the control chamber under normal operation of the pump. In fail safe regulation mode, the electrical valve function is disabled and the pressure controlled valve is active in its second position, controlling pressure in the control chamber. Channels and vents in the pump can be opened and closed based on selective movement of the valve when the outlet pressure is at or above a threshold level.

Systems are provided for an oil system including a filter with a large surface area. In one example, a system may include an oil filter with a prismatic shape. This shape may include a filter surface area greater than an inlet area of an oil port and the filter surface area may also be located a distance away from the oil port.