An oil pressure supply device includes: a first oil pump configured to be operated by a traveling drive source of a vehicle; a second oil pump configured to be operated by a motor different from the traveling drive source and to be switched between an operation and a stop according to a traveling condition of the vehicle; a pressure regulating circuit configured to regulate an oil pressure generated by the first oil pump and the second oil pump and supply the regulated oil pressure to an oil chamber; an oil passage configured to connect the second oil pump with an oil source; and a check valve provided in the oil passage.

A method of controlling an electric oil pump (EOP) of a vehicle includes: confirming a gear shift type when a gear shift of a vehicle is started; compensating for the number of revolutions of the EOP according to the confirmed gear shift type; confirming whether a measured line pressure converges on a command line pressure while the compensating for the number of revolutions of the EOP according to the gear shift type is performed; and, when it is determined that the measured line pressure does not converge on the command line pressure, additionally compensating for the number of revolutions of the EOP.

In a hydraulic control device switchable between a first state in which a first oil is supplied from a first pump to a hydraulic operation part via a bypass valve and a second state in which the first oil supplied from the first pump is pressurized by using the second pump and the pressurized first oil is supplied, as a second oil, to the hydraulic operation part, control that adds a correction hydraulic pressure of a predetermined amount to the hydraulic pressure of the oil discharged from a valve for adjusting the pressure of the oil supplied to the hydraulic operation part is performed when the second state is switched to the first state due to a stop or a low rotation state of the second pump.

The invention relates to a pressure oil filter system for a hydraulic transmission, in particular for a motor vehicle transmission, comprising at least one oil pump which can be actuated as required and which has a pressure side and a suction side, a pressure line to a consumer and at least a first oil filter which is arranged at the pressure side of the oil pump in the pressure line, wherein means for damping pressure surges during intermittent operation of the oil pump are provided in the pressure line upstream of the first oil filter in the flow direction of the oil.

A power supply controller includes a driver having a circuit board and controlling an operation of an electric oil pump, a control unit controlling power supply to the driver, a board temperature sensor detecting a temperature of the circuit board; and an oil temperature sensor detecting a temperature of a working oil of a transmission as an oil temperature. The control unit executes energization prohibition control for prohibiting power supply to the driver when the temperature of the circuit board detected by the board temperature sensor exceeds a predetermined first threshold temperature, and executes cancellation determination for determining whether to cancel the energization prohibition control based on the oil temperature detected by the oil temperature sensor during execution of the energization prohibition control.

Systems, methods, and apparatuses for operating a machine using energy stored in a compress gas are disclosed. Energy stored in the compressed gas may be used to pressurize a fluid, such as transmission fluid, and the pressurized fluid may be used to effectuate an operation of the machine, such as a transmission, and the operation of the machine may involve shifting of a transmission. The gas may be compressed with another fluid that is different from the fluid used to operate the machine, and the two fluid may be prevented from being mixed together.

A method and a system of diagnosing a vehicle oil leak are capable of detecting an oil leak state of transmission oil on the basis of logic. The method includes an operating condition determination step of determining, by a controller, whether a minimum operating condition of a vehicle is satisfied. The minimum operating condition is required to normally generate a target line pressure by operating an EOP. The method includes a counting step of counting, by the controller, an operating time of the EOP when the minimum operating condition is satisfied and includes an oil leak diagnosis step of diagnosing, by the controller, an oil leak when the counted continuous operating time of the EOP is a permissible time or more.

The transmission control unit includes a gear ratio abnormality determination unit and a limp home control unit. The gear ratio abnormality determination unit is configured to determine that a gear ratio is abnormal when, during travelling at a predetermined gear position, a difference between an actual gear ratio, which is calculated based on a transmission input shaft rotation speed and a transmission output shaft rotation speed, and a set gear ratio at the predetermined gear position is equal to or greater than a set value. The limp home control unit is configured to, when the gear ratio abnormality determination unit determines that the gear ratio is abnormal, output a disengagement instruction for disengaging all of the plurality of friction elements, when it is confirmed that a neutral state is shifted to according to the output of the disengagement instruction, determine engagement/disengagement of a specific friction element among the plurality of friction elements based on rotation/stop information of a rotation member of the stepped transmission mechanism, and determine an evacuation gear position based on determination information on the engagement/disengagement of the specific friction element, and shift the gear position to the determined evacuation gear position.

In a hydraulic control device switchable between a first state in which a first oil is supplied from a first pump to a hydraulic operation part via a bypass valve and a second state in which the first oil supplied from the first pump is pressurized by using the second pump and the pressurized first oil is supplied, as a second oil, to the hydraulic operation part, when the second pump is stopped in the second state, control that gradually decreases a target rotation speed of the second pump is performed, and rates at which the target rotation speed of the second pump decreases differ in a case where the second pump is stopped in an operation-allowed region and in a case where the second pump is stopped when the second pump is determined as in an operation-disallowed region.

Provided is a hydraulic control device in which in the rotation control of the second pump, the required discharge pressure of the second pump can be more reliably maintained below a predetermined pressure in the control that keeps the target rotation speed constant after the feedback control ends. In the rotation control of the second pump, in the control which keeps the target rotation speed constant after the feedback control ends, the rotation of the second pump is controlled by adding a predetermined addition rotation speed to the target rotation speed corresponding to the required discharge pressure. Since the required discharge pressure of the second pump can be maintained below a predetermined pressure in the fixed mode by the addition rotation speed, it can reliably obtain the effect of reducing the work load of the first pump and contribute to the improvement of the fuel efficiency of the vehicle.