Abstract: A lockup clutch control apparatus includes a power unit, an automatic transmission, a torque converter, a lockup clutch, an input shaft connected to the power unit, a first output shaft for transmitting the driving force to the automatic transmission; and a second output shaft for transmitting the driving force from the automatic transmission. When a power unit rotation speed or a first output shaft rotation speed becomes equal to, or lower than a first rotation speed, the lockup pressure supplied to the lockup clutch is controlled at a first pressure reduction speed to a target reduced pressure value which is obtained within a range at which the lockup pressure can be controlled. When the lockup pressure becomes the target reduced pressure value, the lockup pressure is reduced at a second pressure reduction speed, which is lower than the first pressure reduction speed, until the lockup clutch starts slipping.

Abstract: Deterioration of drivability due to operation of lock-up clutch mechanism is prevented. When the lock-up operation zone of a lock-up clutch 26 provided in a torque converter 20 is switched from OFF-area to ON-area and to OFF-area again in a predetermined time, a lock-up clutch control unit 50 that controls the lock-up clutch 26 inhibits the lock-up clutch 26 from starting engagement operation. Also, when the lock-up operation zone of the lock-up clutch 26 is switched from OFF-area to ON-area immediately before a shift, the lock-up clutch control unit 50 inhibits the lock-up clutch 26 from starting the engagement operation.

Abstract: A lockup clutch control apparatus includes a power unit, an automatic transmission, a torque converter, a lockup clutch, an input shaft connected to the power unit, a first output shaft for transmitting the driving force to the automatic transmission; and a second output shaft for transmitting the driving force from the automatic transmission. When a power unit rotation speed or a first output shaft rotation speed becomes equal to, or lower than a first rotation speed, the lockup pressure supplied to the lockup clutch is controlled at a first pressure reduction speed to a target reduced pressure value which is obtained within a range at which the lockup pressure can be controlled. When the lockup pressure becomes the target reduced pressure value, the lockup pressure is reduced at a second pressure reduction speed, which is lower than the first pressure reduction speed, until the lockup clutch starts slipping.

Abstract: An automatic transmission apparatus includes: a torque converter including a pump impeller connected to an engine and a turbine connected to an input shaft of an automatic transmission; an oil pump connected to the pump impeller and to the turbine; and a controlling means for selecting one of the engine and the turbine as a driving power source of the oil pump. The oil pump generates an oil pressure by rotation of the selected one of the engine and the turbine.

Abstract: A lock-up clutch controlling device includes a three-dimensional back pressure map, a sensor, and a lock-up pressure controlling unit. The map allows a back pressure of a lock-up piston to be determined from a rotational speed of an engine, an oil temperature, and a speed ratio. The sensor is provided for a parameter influencing the back pressure of the piston. The lock-up pressure controlling unit determines a value equivalent to the back pressure of the lock-up piston from an input value of the sensor and the hydraulic pressure map, and outputs a lock-up pressure to be applied to a lock-up clutch by using the value equivalent to the back pressure of the lock-up piston. When the controlling device operates, it outputs the lock-up pressure by using the value equivalent to the back pressure of the lock-up piston.

Abstract: An automatic transmission apparatus includes: a torque converter including a pump impeller connected to an engine and a turbine connected to an input shaft of an automatic transmission; an oil pump connected to the pump impeller and to the turbine; and a controlling means for selecting one of the engine and the turbine as a driving power source of the oil pump. The oil pump generates an oil pressure by rotation of the selected one of the engine and the turbine.

Abstract: A lock-up clutch controlling device includes a three-dimensional back pressure map, a sensor, and a lock-up pressure controlling unit. The map allows a back pressure of a lock-up piston to be determined from a rotational speed of an engine, an oil temperature, and a speed ratio. The sensor is provided for a parameter influencing the back pressure of the piston. The lock-up pressure controlling unit determines a value equivalent to the back pressure of the lock-up piston from an input value of the sensor and the hydraulic pressure map, and outputs a lock-up pressure to be applied to a lock-up clutch by using the value equivalent to the back pressure of the lock-up piston. When the controlling device operates, it outputs the lock-up pressure by using the value equivalent to the back pressure of the lock-up piston.

Abstract: A control method of a lockup clutch includes eliminating a loss stroke of a piston by a pre-charge of a supplied hydraulic pressure, increasing a force applied to the piston by further supply of the hydraulic pressure after the pre-charge, controlling a slip rotation speed between a pump impeller and a turbine runner in a torque converter connected to an automatic transmission, and determining a time for performing the pre-charge when a shift stage of the automatic transmission is under a neutral state and a vehicle is substantially stopped.

Abstract: A control device for a lock-up mechanism arranged parallel with a hydraulic type torque transmitting mechanism that transmits rotatory power of a pump impeller connected with an output shaft of an engine to a turbine impeller connected with a wheel side element. The lock-up mechanism controls a slip value between the rotational speeds of the pump and turbine impellers in response to supplied hydraulic pressure. The control device calculates a target slip value, detects an actual slip value based on the rotational speed difference of the pump and turbine impellers, sets an intermediate slip value between the actual and target slip values, controls the hydraulic pressure to the lock-up mechanism so that the actual and intermediate slip values coincide, and reduces the intermediate slip value to a renewed value closer to the target slip value than the intermediate slip value when the actual slip value reaches the intermediate slip value.

Abstract: A control method of a lockup clutch includes eliminating a loss stroke of a piston by a pre-charge of a supplied hydraulic pressure, increasing a force applied to the piston by further supply of the hydraulic pressure after the pre-charge, controlling a slip rotation speed between a pump impeller and a turbine runner in a torque converter connected to an automatic transmission, and determining a time for performing the pre-charge when a shift stage of the automatic transmission is under a neutral state and a vehicle is substantially stopped.

Abstract: A control device for a lock-up mechanism arranged parallel with a hydraulic type torque transmitting mechanism that transmits rotatory power of a pump impeller connected with an output shaft of an engine to a turbine impeller connected with a wheel side element. The lock-up mechanism controls a slip value between the rotational speeds of the pump and turbine impellers in response to supplied hydraulic pressure. The control device calculates a target slip value, detects an actual slip value based on the rotational speed difference of the pump and turbine impellers, sets an intermediate slip value between the actual and target slip values, controls the hydraulic pressure to the lock-up mechanism so that the actual and intermediate slip values coincide, and reduces the intermediate slip value to a renewed value closer to the target slip value than the intermediate slip value when the actual slip value reaches the intermediate slip value.