Toyota Jidosha Kabushiki Kaisha

Kei Kitajima

Hitoshi Matsunaga

Yoshio Hasegawa

Masato Kaigawa

Hiroyuki Sawada

Fuminori Monji

Shinya Toyoda

Naoyuki Sakamoto

Masayasu Mizobuchi

In a controller of a vehicle drive unit that is one embodiment of the present invention, a plurality of slippage control regions (regions A to C) are set based on the timing of booming noise generation that accompanies engine driving (time from when the vehicle running state enters a region until booming noise is generated) so as to actively use, for example, regions B and C where booming noise is generated if the road load comes to a balance due to a slope or the like and running is then continued and where booming noise is not immediately generated even after the vehicle running state enters the regions, so the frequency of performing lockup slippage control is increased and the fuel saving effects of the lockup slippage control are enhanced.

Controller of vehicle drive unit

A shift controller for an automatic transmission capable of automatically shifting up in a manual mode is provided. In the shift controller, a hysteresis between an automatic upshift line and a downshift permission line is set to be smaller as the accelerator opening degree decreases. As a result, when the accelerator opening degree is larger and therefore hunting is more likely to occur, it is possible to avoid an excessively small time interval between a downshift and an upshift. On the other hand, when the accelerator opening degree is smaller and therefore hunting is less likely to occur, a manual downshift permission region can be expanded to a higher rotational speed region, whereby a driver's manual downshift request can be satisfied in a higher vehicle speed region.

Shift controller for automatic transmission

A downshift allowable vehicle speed is variably set according to a torque converter slippage amount. Specifically, a downshift allowable vehicle speed is variably set by, using a reference downshift allowable vehicle speed when the torque converter slippage amount is 0 and a gear ratio of the automatic transmission after a downshift, calculating an allowable vehicle speed correction amount based on the present torque converter slippage amount and the gear ratio after the downshift, and setting a value obtained by subtracting the allowable vehicle speed correction amount from the reference downshift allowable vehicle speed as the downshift allowable vehicle speed. By such setting, it is possible to set a higher downshift allowable vehicle speed as the torque converter slippage amount becomes smaller, so it is possible to expand a downshift allowable region when the manual gearshift mode is selected.

Vehicle control apparatus

A control device for an automatic transmissionhaving shift control meansoperative to select a manual shift mode is provided for preventing acceleration response from deteriorating in the automatic transmission. The control device includes automatic up-range control meansfor switching a range to a 'D' range when high oil-temperature determining means determines presence of a high oil-temperature state, and high oil-temperature down-range permitting meansfor permitting a down-range during a manual shift operation until a selected uppermost gear position Greaches a determining gear position Gwhen the accelerator-on drive determining meanssubsequently determines presence of an accelerator-on drive. Even when obtaining a drive force is attempted during an accelerator-on drive mode after switching the range, the down-range by the manual shift operation is permitted until the selected uppermost gear position Greaches the determining gear position G. Thus, a drop in acceleration response in comparison to that of an automatic shift mode is prevented.

Control device for vehicular automatic transmission

A shift controller includes: a shift control unit automatically shifting gears of an automatic transmission using a basic shift line map; a shift line map switching control unit switching from the basic shift line map to a high fluid temperature shift line map set on a lower vehicle speed side when a hydraulic fluid temperature in the automatic transmission is higher than a predetermined value; and a low power state determination unit determining whether a vehicle is in a low power state in which a required power related value used for gear shift determination is lower than a predetermined determination value. The shift line map switching control unit switches from the high fluid temperature shift line map back to the basic shift line map when the hydraulic fluid temperature is lower than the predetermined value and the vehicle is in the low power state.

Shift controller of vehicle automatic transmission

Until the accuracy in calculation of an estimated oil temperature value which is calculated by means of a heat dissipation amount map reaches a predetermined level, an ECU determines, when a transmission oil temperature well exceeds a predetermined temperature after the engine start, whether or not an oil temperature sensor fails. When it is determined that the oil temperature sensor is normal, the ECU uses the detected oil temperature value to learn about the heat dissipation map. When the accuracy in calculation of the estimated oil temperature value reaches the predetermined level through the learning about the heat dissipation amount map, the ECU determines whether or not the oil temperature sensor fails based on the divergence of the detected oil temperature value relative to the estimated oil temperature value.

Abnormality determination apparatus and abnormality determination method for oil temperature sensor

Provided are an automatic transmission abnormality diagnosis apparatus and method for an automatic transmission having: a lock-up mechanism; a shift mechanism; and a control mechanism. The automatic transmission is adapted to operate in a slip state, a full lock-up state or a lock-up release state of the lock-up mechanism. The lock-up mechanism is forcibly shifted from the slip state or from the lock-up release state to the full lock-up state in an operation region where the lock-up mechanism is not normally placed in the full lock-up state, and then whether the forcible shift of the lock-up mechanism has been successfully performed is determined. As such, the region for executing the abnormality diagnosis of the hydraulic control mechanism is extended and thus the frequency of the abnormality diagnosis increases, and therefore abnormalities can be promptly detected.

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Toyota, Japan

Kei Kitajima