A variable oil pump includes a pump housing, an oil pump rotor accommodated in the pump housing, an adjustment member accommodated in the pump housing and configured to adjust a discharge amount of oil discharged from the oil pump rotor by displacing in a state where the adjustment member holds the oil pump rotor from an outer circumferential side in such a manner that the oil pump rotor is rotatable, and a guide portion including a guide hole provided at the adjustment member and a pin provided at the pump housing and engaging with the guide hole. The guide portion is configured to guide a displacement of the adjustment member relative to the pump housing by allowing the guide hole and the pin to engage with each other. The variable oil pump includes a drain passage configured to drain oil accumulated in the guide hole.

A hydraulic control apparatus is provided including: an electromagnetic valve that has an input port communicating with a supply destination unit of oil and a control port that is switched between communication and disconnection by resultant force of a hydraulic pressure of the supply destination unit and electromagnetic force; a variable displacement pump which has a suction port communicating with a supply source of the oil, an ejection port communicating with the supply destination unit, and a control chamber communicating with the control port and rotates in accordance with drive of the supply destination unit, in which an amount of the oil ejected to the supply destination unit through the ejection port changes in accordance with a pressure in the control chamber; and a control unit that controls a value of a necessary current that is caused to flow through the electromagnetic valve.

An object of the present invention is to simplify portions of an oil supply passage which portions are formed at a cylinder block. An oil supply device according to the present invention includes a cylinder block, an oil pan, an oil pump, and an oil filter. Wall portions of the oil pan are coupled to wall portions of the cylinder block. An oil filter is attached to the oil pan. An upstream oil supply passage through which the oil filtrated by the oil filter flows is formed at the oil pan. A downstream oil supply passage including a main gallery extending in a cylinder column direction is formed at the cylinder block. A first communication passage through which the main gallery and the upstream oil supply passage communicate with each other is formed at the wall portion of the cylinder block and the wall portion of the oil pan.

A method for diagnosing a failure of a solenoid valve of a piston cooling device is provided. The method includes varying a pressure in a variable proportional control oil pump when an opening command or a closing command of the solenoid valve is sent to inject oil from the piston cooling device. Additionally, a variation of an oil pressure in an oil flow path of the piston cooling device is monitoring according to a variation of the pressure in the variable proportional control oil pump and whether a failure occurs at the solenoid valve of the piston cooling device is then determined.

An oil supply device for an internal combustion engine includes: a variable displacement pump (1) that varies a discharge pressure at which oil is discharged; an oil passage (2) through which the oil discharged from the pump (1) flows; an oil filter (3) and an oil cooler (4) each of which is arranged in the oil passage (2); a bypass passage (5) connected to the oil passage (2) and bypassing the oil cooler (4); and a bypass valve (6) that opens and closes the bypass passage (5) according to a pressure of the oil. The bypass valve (6) is operated to control the flow of the oil through the oil cooler 4 as the discharge pressure of the pump (1) is adjusted according to operating conditions of the internal combustion engine.

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 adjustable vane pump, in particular an oil pressure pump, with a suction side and a pressure side, with a housing and a rotor supported in the housing so as to be rotatable about a rotor axis. At least one vane is supported for movement in a radial direction. The housing comprises a housing floor and a housing cover transversely to the rotor axis, and an adjustment cage is arranged between the housing floor and the housing cover.

Variable displacement pumps and biasing assemblies for the same are disclosed. Example pumps may include a housing having an inlet and an outlet, and a rotor fixed for rotation with a shaft, with the shaft rotatably mounted within the housing. The pump may further include a plurality of radially extending vanes slidably disposed in the rotor, and a pivotable ring member defining a control chamber about the rotor, with the ring member being pivotable within the housing to vary an eccentricity of the ring member with respect to the rotor. The pump may further include a biasing assembly applying a biasing force to the ring member in a first direction about the shaft, with the biasing assembly including at least one resilient element extending longitudinally along a stand, and a sliding support slidably disposed on the stand and laterally supporting the resilient element with respect to the stand.

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 lubrication system for an internal combustion engine includes a fluid flow control device at an outlet side of the pump that regulates pressure conditions at the outlet side of the pump upstream of the lubrication circuit in the engine. The fluid flow control device is located in a recirculation path, and opens in response to a fluid pressure at the outlet of the pump exceeding a first threshold to allow the fluid to pass from the outlet side of the pump back to an inlet side of the pump. The recirculation path includes a tuning device that maintains the fluid pressure at engine speeds above the first threshold. In response to engine speeds above a second threshold, the tuning device restricts fluid flow in the recirculation path so that the fluid pressure in the fluid flow path increases.