Abstract: An automatic transmission where the control portion controls the adjustment solenoid valve so that the circulation hydraulic pressure equals to a second circulation hydraulic pressure higher than the first circulation hydraulic pressure when the rotational speed difference between the output rotational speed of the fluid transmission device and the rotational speed of the driving source is more than the predetermined rotational speed.

Abstract: A power transmission device that includes a transmission including a plurality of engagement elements for transmitting power from a motor to axles; a case to accommodate the transmission; a hydraulic control device to control hydraulic pressure to the engagement elements; a hydraulic oil reservoir that stores hydraulic oil; and a first pump that is operated by the power from the motor and that suctions the hydraulic oil from the hydraulic oil reservoir through a strainer and supplies the hydraulic oil to the hydraulic control device.

Abstract: An automatic transmission where the control portion controls the adjustment solenoid valve so that the circulation hydraulic pressure equals to a second circulation hydraulic pressure higher than the first circulation hydraulic pressure when the rotational speed difference between the output rotational speed of the fluid transmission device and the rotational speed of the driving source is more than the predetermined rotational speed.

Abstract: A power transmission device that is mounted on a vehicle and provided with a transmission having a plurality of engagement elements for transmitting power from a motor to an axle, a case that accommodates the transmission, and a hydraulic control device that controls hydraulic pressure to the plurality of engagement elements.

Abstract: A hydraulic control apparatus, wherein the first switching valve receives an input of one of the hydraulic pressure from the first electromagnetic valve device and the predetermined hydraulic pressure from the third switching valve, as a switching signal pressure, the first switching valve is switched from the first state to the second state in response to the input of the switching signal pressure, and the first switching valve is held in the second state, and the second switching valve receives an input of one of the hydraulic pressure from the first electromagnetic valve device and the predetermined hydraulic pressure from the third switching valve, as a holding pressure for holding the normal supply state.

Abstract: A power transmission device that includes a transmission including a plurality of engagement elements for transmitting power from a motor to axles; a case to accommodate the transmission; a hydraulic control device to control hydraulic pressure to the engagement elements; a hydraulic oil reservoir that stores hydraulic oil; and a first pump that is operated by the power from the motor and that suctions the hydraulic oil from the hydraulic oil reservoir through a strainer and supplies the hydraulic oil to the hydraulic control device.

Abstract: A hydraulic control apparatus, wherein the first switching valve receives an input of one of the hydraulic pressure from the first electromagnetic valve device and the predetermined hydraulic pressure from the third switching valve, as a switching signal pressure, the first switching valve is switched from the first state to the second state in response to the input of the switching signal pressure, and the first switching valve is held in the second state, and the second switching valve receives an input of one of the hydraulic pressure from the first electromagnetic valve device and the predetermined hydraulic pressure from the third switching valve, as a holding pressure for holding the normal supply state.

Abstract: A power transmission device that is mounted on a vehicle and provided with a transmission having a plurality of engagement elements for transmitting power from a motor to an axle, a case that accommodates the transmission, and a hydraulic control device that controls hydraulic pressure to the plurality of engagement elements.

Abstract: A hydraulic control device configured with a source pressure generation section, a hydraulic servo for a clutch provided between an engine and a motor, a control solenoid valve that outputs a regulated source pressure to the hydraulic servo, and a switching section that switches a hydraulic passage, which extends between the source pressure generation section and the hydraulic servo to supply the engagement pressure, between a first and second state in which the hydraulic passage has a high conduit resistance compared to the first state at least until the clutch is engaged. The switching section switches the hydraulic passage into the second state during a failure in which the control solenoid valve is de-energized and the source pressure is directly supplied to the hydraulic servo as the engagement pressure, and switches the hydraulic passage into the first state during normal times when the failure does not occur.

Abstract: Mutual interference between a hydraulic pressure of a first engagement device and a hydraulic pressure of a second engagement device is suppressed even in the case where operation of the first engagement device and operation of the second engagement device coincide with each other. A vehicle drive device includes a first engagement device that selectively couples a rotary electric machine to an internal combustion engine, and a fluid coupling. The first engagement device includes a first oil chamber that is formed to apply a back pressure to a first piston. The fluid coupling includes a second oil chamber configured to control an engagement state of a second engagement device. The vehicle drive device includes a first control valve that controls a first oil chamber hydraulic pressure, and a second control valve that controls a second oil chamber hydraulic pressure independently of the first oil chamber hydraulic pressure.

Abstract: A hydraulic control device configured with a source pressure generation section, a hydraulic servo for a clutch provided between an engine and a motor, a control solenoid valve that outputs a regulated source pressure to the hydraulic servo, and a switching section that switches a hydraulic passage, which extends between the source pressure generation section and the hydraulic servo to supply the engagement pressure, between a first and second state in which the hydraulic passage has a high conduit resistance compared to the first state at least until the clutch is engaged. The switching section switches the hydraulic passage into the second state during a failure in which the control solenoid valve is de-energized and the source pressure is directly supplied to the hydraulic servo as the engagement pressure, and switches the hydraulic passage into the first state during normal times when the failure does not occur.

Abstract: Mutual interference between a hydraulic pressure of a first engagement device and a hydraulic pressure of a second engagement device is suppressed even in the case where operation of the first engagement device and operation of the second engagement device coincide with each other. A vehicle drive device includes a first engagement device that selectively couples a rotary electric machine to an internal combustion engine, and a fluid coupling. The first engagement device includes a first oil chamber that is formed to apply a back pressure to a first piston. The fluid coupling includes a second oil chamber configured to control an engagement state of a second engagement device. The vehicle drive device includes a first control valve that controls a first oil chamber hydraulic pressure, and a second control valve that controls a second oil chamber hydraulic pressure independently of the first oil chamber hydraulic pressure.

Abstract: A hydraulic control device for an automatic transmission that includes a fail-safe function to establish a fail-safe traveling state where a predetermined shift speed is established, and a fail-safe stopping state where the primary pressure to all of the hydraulic servos is cut-off when a failure occurs. The hydraulic control device is able to switch between the fail-safe traveling state and the fail-safe stopping state even after a failure occurs, thereby enhancing a limp-mode function.

Abstract: A hydraulic control device for a multi-speed automatic transmission includes friction engagement elements, several hydraulic servos that engage and release the friction engagement elements, solenoid valves for engagement control, and a sorting switch valve that allocates engagement pressure from at least one of the solenoid valves for engagement control to two of the hydraulic servos. The sorting switch is switched between a first position that supplies engagement pressure to one of the two hydraulic servos in at least a Reverse, non-drive range and a specific Forward gear range, and a second position that supplies engagement pressure to the two hydraulic servos in other than the Forward range.

Abstract: A hydraulic control apparatus of an automatic transmission having engagement pressure solenoid valves configured to regulate an engagement pressure supplied to a hydraulic servo of a frictional engagement element and to output the engagement pressures from a predetermined number of the engagement pressure solenoid valves to establish respective transmission gear speeds.

Abstract: A parking switching valve includes a spool that is movable to a first position and to a second position. The parking switching valve also has an oil chamber that generates a biasing force from a difference in the pressure receiving area between the land portions of the spool. The oil chamber has a second input port to which a line pressure is input while the spool is in the second position. Because the line pressure is input to the second input port, a biasing force is generated so that the spool is held in the second position against a spring. As a result, a parking device is held in a parking release state.

Abstract: A vehicle hydraulic control device for driving a parking rod to a parking disengagement position and a parking engagement position, and switching a shift range at least between a parking range and a non-parking range by switching an engagement state of a parking gear and a parking pole. The vehicle hydraulic control device includes a parking cylinder and a switch valve. The parking cylinder receives an oil pressure for driving the parking rod to the parking disengagement position. The switch valve is driven based on an electric actuator and switches an operation state between a parking disengagement state in which a source pressure from an oil pressure supply source is supplied to the parking cylinder as a disengagement pressure for disengaging the parking gear and the parking pole from each other, and a parking engagement state in which the disengagement pressure is not supplied to the parking cylinder.

Abstract: A hydraulic control apparatus of an automatic transmission having engagement pressure solenoid valves configured to regulate an engagement pressure supplied to a hydraulic servo of a frictional engagement element and to output the engagement pressures from a predetermined number of the engagement pressure solenoid valves to establish respective transmission gear speeds.

Abstract: A hydraulic control device for a multi-speed automatic transmission includes friction engagement elements, several hydraulic servos that engage and release the friction engagement elements, solenoid valves for engagement control, and a sorting switch valve that allocates engagement pressure from at least one of the solenoid valves for engagement control to two of the hydraulic servos. The sorting switch is switched between a first position that supplies engagement pressure to one of the two hydraulic servos in at least a Reverse, non-drive range and a specific Forward gear range, and a second position that supplies engagement pressure to the two hydraulic servos in other than the Forward range.

Abstract: A hydraulic control device for an automatic transmission that includes a fail-safe function to establish a fail-safe traveling state where a predetermined shift speed is established, and a fail-safe stopping state where the primary pressure to all of the hydraulic servos is cut-off when a failure occurs. The hydraulic control device is able to switch between the fail-safe traveling state and the fail-safe stopping state even after a failure occurs, thereby enhancing a limp-mode function.