A method of controlling an automatic transmission is provided. The automatic transmission includes a piston having first and second surfaces opposite from each other, friction plates, engaging and disengaging hydraulic pressure chambers for supplying/discharging hydraulic pressure and directing the piston to push the friction plates to be engaged and disengaged, a hydraulic pressure control valve for supplying/discharging hydraulic pressure to/from the chambers, and first and second oil paths communicating the valve with the chambers. The second surface has a larger area for receiving hydraulic pressure than the first surface. The method includes controlling the disengaged friction plates to be engaged by adjusting the hydraulic pressure to a first pressure in a first period in response to a gear shift command and adjusting the hydraulic pressure to a second pressure in a second period. The first pressure is changed depending on a state of the automatic transmission.

A transmission combination includes a hydrostatic transmission and a mechanical transmission having a clutch and a control device for calibrating a grinding point of the clutch. A traction drive includes the transmission combination. A method includes calibrating the clutch.

In a control device for a vehicle including: a dog clutch mechanism that is disposed in a power transmission path in which a driving force is transmitted from an engine to a wheel and is operated by a hydraulic actuator; and an electric oil pump that supplies hydraulic pressure to the hydraulic actuator, rotation of the engine is stopped in a state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine stop operation, the rotation of the engine is started in the state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine restart operation, hence occurrence of up-lock of the dog clutch mechanism is prevented.

A method of controlling an automatic transmission is provided. The automatic transmission includes a piston having first and second surfaces opposite from each other, friction plates, engaging and disengaging hydraulic pressure chambers for supplying and discharging hydraulic pressure and directing the piston to push the friction plates to be engaged and disengaged, a hydraulic pressure control valve for supplying and discharging hydraulic pressure to and from the chambers, first and second oil paths communicating the valve with the chambers, and a pressure reducing valve disposed in the second oil path and for preventing hydraulic pressure of the disengaging hydraulic pressure chamber from exceeding a given set pressure. The second surface has a larger area for receiving hydraulic pressure than an area of the first surface for receiving hydraulic pressure. The method includes changing the given set pressure according to information regarding a state of the automatic transmission.

There is obtained an automatic transmission control apparatus that makes it possible that even when an abnormality occurs in a sensor for detecting a motor rotation angle or the like, control of an automatic transmission is appropriately performed. Inputted first, second, and third detection signals are compared with one another; it is determined that at least two detection signals, out of these detection signals, that coincide with each other are normal and another detection signal is abnormal; then, based on the result of the determination, switching of the ranges of the automatic transmission is controlled.

A position sensor system is useful for monitoring positions of shifters in transmissions and other applications. The position sensing system has an array of magneto resistive sensors and a controller configured to determine a position of a magnet along a path by triangulation. Some embodiments are relatively insensitive to fluctuations in a distance between the sensors and the path. Also described is an actuating assembly comprising a movable cylinder and a fixed rod. The actuating assembly may be applied for moving synchronizers or the like in power transmissions.

Method for regulating the control of an electrical wastegate actuator controlled via an H bridge to permit displacement of the wastegate in its closure and opening directions according to whether the current passes through the actuator in one or opposite direction, includes: determining a set position which the wastegate has to reach, and an activation time of the actuator defining a monitoring time; applying a control signal to the actuator to displace the valve into the set position; measuring the current passing through the H bridge and applying a correction factor to the current to obtain the motor torque; obtaining the displacement speed of the wastegate by integration of the motor torque; obtaining the position reached by the wastegate at the end of the monitoring time by integration of the speed; comparing the position reached with the set position; and repeating the method until the set position is reached.

A shift device includes: a shift switching member including valley portions corresponding to shift positions; a motor including a rotor and a stator and configured to drive the shift switching member; a first drive system including a first control unit configured to control a voltage for driving the motor; a second drive system provided separately from the first drive system and including a second control unit configured to control a voltage for driving the motor; and a positioning member configured to establish the shift positions in a state in which the positioning member is fitted into any one of the valley portions of the shift switching member. The shift device acquires the shift positions when the motor is driven by the voltage output from one of the first and second drive systems to move the positioning member such that the positioning member continuously passes through the valley portions.

An actuator system comprising a shared link arranged to pivot about a first axis relative to a reference structure, a controlled element arranged to pivot about a second axis relative to the reference structure, a first member arranged to pivot about a third axis relative to the shared link and a fourth axis relative to the controlled member, a first actuator arranged to control a first variable distance between the third axis and fourth axis, a second member arranged to pivot about a fifth axis relative to the shared link and a sixth axis relative to the controlled element, a second actuator arranged to control a second variable distance between the fifth axis and the sixth axis, the system configured such that a change in the first variable distance causes rotation of the controlled element about the second axis when the second variable distance is constant and vice versa.

A hydraulic control system for a dual clutch transmission includes a plurality of solenoids and valves in fluid communication with a plurality of clutch actuators and with a plurality of synchronizer actuators. The clutch actuators are operable to actuate a plurality of torque transmitting devices and the synchronizer actuators are operable to actuate a plurality of synchronizer assemblies. Selective activation of combinations of the solenoids allows for a pressurized fluid to activate at least one of the clutch actuators and synchronizer actuators in order to shift the transmission into a desired gear ratio.