Abstract: A hydraulic control device that includes two hydraulic oil chambers, wherein a predetermined engagement element of the engagement elements is an engagement element that includes the two hydraulic oil chambers and is engageable and disengageable when an engagement pressure is supplied to and discharged from at least one of the two hydraulic oil chambers, and a control unit that reduces supply of the engagement pressure to one of the two hydraulic oil chambers to a level lower than that in a state in which a first shift speed is established, when the control unit performs shifting from the state in which the first shift speed is established by supplying the engagement pressures to both of the two hydraulic oil chambers and engaging the predetermined engagement element to a second shift speed by switching engagement and disengagement states of engagement elements other than the predetermined engagement element.

Abstract: A hydraulic control device for an automatic transmission, wherein when the first switching valve is switched to the first state while the second switching valve is in the third state, the reverse range pressure applied from the reverse range pressure input port of the second switching valve can be supplied from the first output port to the hydraulic servo for the first friction engagement element via the fourth output port of the second switching valve and the first input port of the first switching valve, and when a shift range is shifted from a neutral range to a reverse range, the second switching valve is in the fourth state, and the first switching valve is switched from the first state to the second state, so that the reverse range pressure applied to the reverse range pressure input port is cut off by the second switching valve.

Abstract: A hydraulic device wherein an orifice is provided upstream of the discharge valve in an oil passage from the electric pump, a drain oil passage from the second hydraulic servo communicates between the orifice and the discharge valve in the oil passage from the electric pump, and an oil pressure in the oil passage upstream of the orifice is maintained at a predetermined pressure higher than the set pressure.

Abstract: A hydraulic control device that includes a pressure regulating valve capable of regulating a source pressure to generate a control pressure higher than the oil pressure in the circulation oil chamber and supplying the control pressure to the engagement port, wherein when disengaging the lockup clutch, the hydraulic oil is circulated in the circulation oil chamber via the circulation input port and the circulation output port, and part of the hydraulic oil circulated in the circulation oil chamber is supplied to the engagement port, and when engaging the lockup clutch, the supply of the hydraulic oil circulated in the circulation oil chamber to the engagement port is cut off, and the control pressure is supplied to the engagement port.

Abstract: A hydraulic control device includes a lock-up control valve that regulates a line pressure to generate a control pressure, and a lock-up relay valve that switches between paths through which a hydraulic pressure is supplied to and discharged from a torque converter. The lock-up relay valve is formed to be capable of switching between a path that connects between a control pressure oil passage to which the control pressure is output and a lock-up oil passage communicated with a lock-up oil chamber and that connects between a control pressure oil passage to which the control pressure is output and a circulation input oil passage communicated with a converter oil chamber, and a path that blocks connection between the control pressure oil passage and the lock-up oil passage and that blocks connection between the control pressure oil passage and the circulation input oil passage.

Abstract: A hydraulic control device that controls a hydraulic pressure for a plurality of friction engagement elements included in an automatic transmission mounted on a vehicle to establish a plurality of shift speeds, including: a plurality of pressure regulation valves, a plurality of hydraulic switches, speed change control means, and abnormality determination means.

Abstract: A hydraulic control device includes a lock-up control valve that regulates a line pressure to generate a control pressure, and a lock-up relay valve that switches between paths through which a hydraulic pressure is supplied to and discharged from a torque converter. The lock-up relay valve is formed to be capable of switching between a path that connects between a control pressure oil passage to which the control pressure is output and a lock-up oil passage communicated with a lock-up oil chamber and that connects between a control pressure oil passage to which the control pressure is output and a circulation input oil passage communicated with a converter oil chamber, and a path that blocks connection between the control pressure oil passage and the lock-up oil passage and that blocks connection between the control pressure oil passage and the circulation input oil passage.

Abstract: A control device for an automatic transmission that outputs a command signal to an actuator to control the automatic transmission. The control device configured with a main control section that receives a state of the automatic transmission, that determines an abnormality in the automatic transmission on the basis of the input state of the automatic transmission, and that outputs to the actuator a main control section command signal for controlling the automatic transmission so as to establish a predetermined shift speed when it is determined that an abnormality is occurring in the automatic transmission; and a monitoring section that determines an abnormality in the main control section and that outputs to the actuator a monitoring section command signal for causing the automatic transmission to establish a neutral state irrespective of the main control section command signal when it is determined that an abnormality is occurring in the main control section.

Abstract: An automatic transmission including an input shaft connected to a drive source; an output shaft connected to a driving wheel; a one-way clutch; friction engagement elements which establish speeds by changing a transmission path between the input shaft and the output shaft based on the application state of the friction engagement elements and application of the one-way clutch, one of the friction engagement elements being a brake that is applied when coasting in a take-off speed. The automatic transmission also includes a controller that determines whether it is possible to initially establish the take-off speed using the one-way clutch based on a predetermined condition, and, if not possible, then the controller establishes the take-off speed by applying the brake.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: A hydraulic control device that controls a hydraulic pressure to be supplied to a hydraulic servo for a hydraulically driven friction engagement element in an automatic transmission that changes between shift speeds by switching an engagement state of the friction engagement element. The control device configured with a switching mechanism that allows communication between oil passage for a first pressure regulation mechanism and the oil passage for a hydraulic servo and blocking communication between an oil passage for the second pressure regulation mechanism and the oil passage for the hydraulic servo when the signal pressure is not input to the signal pressure input oil passage, and blocking communication between the oil passage for the first pressure regulation mechanism and the oil passage for the hydraulic servo and allowing communication between the oil passage for the second pressure regulation mechanism.

Abstract: A fluid pressure control device including a first pump actuated by power from a motor; a pressure regulator that regulates a discharge pressure from the first pump; a second pump actuated by electric power; a switcher opening a first path extending from the pressure regulator to a fluid pressure chamber of a friction engagement element, and blocking a second path extending from the second pump to the fluid pressure chamber of the friction engagement element, when the signal pressure is equal to or more than a set pressure, and the switcher blocking the first and opening the second paths when the signal pressure is less than the set pressure; and a control that controls the second pump and the fluid supply unit to supply the fluid regulated by the pressure regulator to a destination different from the fluid pressure chamber of the friction engagement element when the motor is stopped.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: A hydraulic control device controls a hydraulic pressure in an engagement side oil chamber defined on one side of a piston that configures a hydraulic clutch, and a hydraulic pressure in a back-pressure side oil chamber defined on the other side of the piston. The hydraulic control device includes a line pressure generating valve that generates a line pressure by adjusting a hydraulic pressure from an oil pump; a secondary pressure generating valve that generates a secondary pressure, which is a hydraulic pressure supplied to the back-pressure side oil chamber, by adjusting a hydraulic pressure from the line pressure generating valve so as to be lower than the line pressure; and a clutch engagement pressure generating valve that generates a clutch engagement pressure, which is a hydraulic pressure supplied to the engagement side oil chamber, by adjusting the line pressure from the line pressure generating valve.

Abstract: A fluid pressure control device including a first pump actuated by power from a motor; a pressure regulator that regulates a discharge pressure from the first pump; a second pump actuated by electric power; a switcher opening a first path extending from the pressure regulator to a fluid pressure chamber of a friction engagement element, and blocking a second path extending from the second pump to the fluid pressure chamber of the friction engagement element, when the signal pressure is equal to or more than a set pressure, and the switcher blocking the first and opening the second paths when the signal pressure is less than the set pressure; and a control that controls the second pump and the fluid supply unit to supply the fluid regulated by the pressure regulator to a destination different from the fluid pressure chamber of the friction engagement element when the motor is stopped.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: A control device for an automatic transmission that outputs a command signal to an actuator to control the automatic transmission. The control device configured with a main control section that receives a state of the automatic transmission, that determines an abnormality in the automatic transmission on the basis of the input state of the automatic transmission, and that outputs to the actuator a main control section command signal for controlling the automatic transmission so as to establish a predetermined shift speed when it is determined that an abnormality is occurring in the automatic transmission; and a monitoring section that determines an abnormality in the main control section and that outputs to the actuator a monitoring section command signal for causing the automatic transmission to establish a neutral state irrespective of the main control section command signal when it is determined that an abnormality is occurring in the main control section.

Abstract: A hydraulic control device that controls a hydraulic pressure to be supplied to a hydraulic servo for a hydraulically driven friction engagement element in an automatic transmission that changes between shift speeds by switching an engagement state of the friction engagement element. The control device configured with a switching mechanism that allows communication between oil passage for a first pressure regulation mechanism and the oil passage for a hydraulic servo and blocking communication between an oil passage for the second pressure regulation mechanism and the oil passage for the hydraulic servo when the signal pressure is not input to the signal pressure input oil passage, and blocking communication between the oil passage for the first pressure regulation mechanism and the oil passage for the hydraulic servo and allowing communication between the oil passage for the second pressure regulation mechanism.

Abstract: A hydraulic control device for an automatic transmission includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a preliminary shift speed switching valve, and a hydraulic pressure supply switching valve. A second friction engagement element is engaged at high speed side shift speeds, a low speed that is one of low speed side shift speeds is achieved by engagement of a first friction engagement element and a third friction engagement element, and a high speed that is one of the high speed side shift speeds is achieved by engagement of a second friction engagement element and the third friction engagement element.

Abstract: A valve assembly includes a plurality of solenoid valves, each solenoid valve having a pressure-regulating valve portion formed by a sleeve having a plurality of valve-side ports and a spool for opening and closing the valve-side ports, and a solenoid portion having a plunger for driving the spool and a coil for electromagnetically driving the plunger; and a valve body having a plurality of insertion holes into which the solenoid valves are inserted, and having ports that are connected to the plurality of valve-side ports in a state in which the solenoid valves are mounted.