Abstract: An abnormality determination device of a lock up clutch includes a controller and a determining unit. The controller sets a lock up clutch in a torque converter at an engaged state or a disengaged state. The torque converter is provided in an automatic transmission of a vehicle. The determining unit determines, on the condition that deceleration of the vehicle on travel with the lock up clutch in the engaged state causes a control signal for disengagement to be outputted from the controller, the presence or the absence of the abnormality in the lock up clutch, on the basis of a determination result as to whether or not a difference between the number of engine rotations and the number of turbine rotations is equal to or larger than a first threshold that varies with a rate of deceleration of the vehicle.

Abstract: A method for operating an automatic transmission is provided. The method includes disengaging a shifting element of the automatic transmission and measuring an input speed of the automatic transmission while the shifting element is disengaging. A command pressure of the shifting element is adjusted to a target command pressure based at least in part on the input speed of the automatic transmission while the shifting element is disengaging.

Abstract: An automatic transmission control unit determines whether or not a constantly open failure, in which a switch valve cannot switch a pressure regulating valve and a second hydraulic chamber to a non-communicative state, has occurred on the basis of a parameter (an inertia phase time, for example) representing a dynamic characteristic during a shift from a first gear position to a second gear position. The determination of the constantly open failure is begun after initial variation in the parameter representing the dynamic characteristic during the shift has been eliminated through learning control in which the dynamic characteristic during the shift is caused to approach a target dynamic characteristic.

Abstract: A radio communication method and system employs power level presetting to mitigate the increase in interference caused by the discontinuous transmission of mobile stations. In the downlink, power presetting entails detecting the entry (or removal) of mobile stations to a cell, and in response thereto, calculating a plurality of power adjustment values for each mobile station within the cell. In the uplink, power presetting entails estimating an increase in interference caused by the entry (or removal) of mobile stations to a cell, and using this estimate for calculating an updated power target for each mobile station within the cell. Power presetting is also initiated in response to one or more mobile stations switching from high data-rate mode to low data-rate mode, or vice versa.

Abstract: A control system for an automatic transmission includes a clutch for transmitting the rotation of a fluid transmission unit to a speed change mechanism of a transmission and a hydraulic servo for applying/releasing the clutch. A stop state detector is provided for detecting the stop state of the vehicle. A release control oil pressure changer lowers the oil pressure of the hydraulic servo by a first set pressure when the vehicle stop state is detected. An in-neutral control oil pressure changer raises the oil pressure of the hydraulic servo by a second set pressure, when the difference between the input side RPM and the output side RPM of the fluid transmission unit has not changed, and lowers the same by a third set pressure when the rotational speed difference has changed. The first set pressure is different from the second and third set pressures.

Abstract: A line pressure control apparatus of an automatic transmission controls the line pressure of the automatic transmission under a lockup condition to ensure an engagement capacity and an amount of lubrication oil for an engaged friction element under a high vehicle speed condition. The line pressure control apparatus comprises a line pressure lowering section, a vehicle speed deciding section and a pressure changing section. The pressure lowering section lowers a line pressure under a lockup condition of the automatic transmission. The vehicle speed deciding section decides whether a vehicle speed of the automotive vehicle is higher than a predetermined value. The pressure changing section changes the line pressure under the lockup condition from the lowered line pressure to a line pressure under a normal condition when the vehicle speed is higher than the predetermined value.

Abstract: An automatic transmission control system providing a neutral control state in which there is no slipping engagement of a first clutch which is engaged upon selection of a forward range and, as a result, the vehicle is not subjected to idling vibration. The fuel consumption reducing effect of the neutral control state is maintained and there is no heating and consequent deterioration of the friction material of the clutch. The control system includes a hydraulic servo for operation of the clutch, an input side speed sensor for detecting the input side speed of a fluid power coupling device connecting the transmission to the output of an engine, an output side speed sensor for detecting the output side speed of the fluid power coupling device, and a controller.

Abstract: An electronically controlled multiply ratio transmission for an automotive vehicle powertrain having a hydrokinetic torque converter with a bypass clutch, solenoid operated shift valves under the control of an electronic microprocessor that receives signals from an output shaft speed sensor, an engine speed sensor, a driver controlled drive range selector position, an engine throttle position sensor, and other powertrain operating variables, the bypass clutch having a controlled slip characteristic.

Abstract: A speed-changing hydraulic oil pressure control apparatus for controlling speed-changing hydraulic oil pressure according to a transition state of the speed change in an automatic transmission. The controllability is improved by detecting in advance the transfer from a torque phase to an inertia phase by detecting the output torque of the transmission and the input revolution number and output revolution number of a torque converter. The input torque of the transmission is estimated from the input revolution number and output revolution number of the torque converter, and the transition state of the speed change is detected from the input torque and output torque of the transmission. By comparing input torque and output torque of the transmission, the transfer from the torque phase to the inertia passe is detected in advance by utilizing the phenomenon of a large fall of the output torque of the transmission just before the transfer to the inertia phase from the torque phase.