Toyota Jidosha Kabushiki Kaisha

Toyota Jidoshi Kabushiki Kaisha

Yoshiaki Yamamoto

Daisuke Inoue

Hiroji Taniguchi

Tadashi Tamura

Katsumi Kono

Hiroki Kondo

Hideki Yasue

Kenji Matsuo

Yuji Hattori

Ryoji Habuchi

Hiroshi Morioka

Zenichiro Mashiki

Isao Takagi

Hirofumi Kubota

Hiroya Tanaka

Tetsuo Hamajima

Syoichi Sayo

Shinichi Matani

When the temperature of operating fluid of an actuator is low, a target input rotation speed lower limit value (NinL) is set. The lower limit value (NinL) is greater than a lower limit value set for a normal temperature of operating fluid. A target input rotation speed (Nint) is calculated from the state of running of a vehicle, such as the amount of operation of an accelerator, the vehicle speed, etc. If the target input rotation speed is lower than the lower limit value (NinL), the target input rotation speed is reset to the lower limit value (NinL). As a result of a control that includes the above-described steps, the speed ratio &ggr; becomes relatively high before the vehicle stops. Therefore, even if the speed ratio-changing rate is low, the speed ratio (&ggr;) can be brought to or near a maximum value (&ggr;max) before the vehicle stops. Thus, reductions in the speed ratio-changing rate caused by low temperature of the operating fluid of the actuator can be curbed.

Shift control apparatus and shift control of continuously variable transmission

A vehicle drive apparatus has a pump that supplies operating fluid for performing speed shift control of a power transfer apparatus, and a driving motor that drives the pump. If it is determined that the power transfer apparatus is in a neutral state (N range), it is then determined whether the vehicle is running. If the vehicle is running, it is determined whether the operation speed of the driving motor has reached a speed that allows the pump to produce a predetermined fluid pressure. If that speed has not been reached, the motor operation speed is controlled to the speed that allows the pump to produce the predetermined fluid pressure. The vehicle drive apparatus secures a pressure and a flow of fluid when the power transfer apparatus is operated to the neutral state during the running of the vehicle.

Vehicle drive apparatus and control method thereof

An apparatus and a method control a continuously variable transmission of a motor vehicle which includes a power transmitting member for power transmission by use of friction. A controller of the apparatus detects slippage of the power transmitting member in a predetermined period of running of the vehicle, and increases a clamping pressure that is applied to the power transmitting member when slippage of the power transmitting member is detected. The controller also stores a state of increase of the clamping pressure in a memory, and increases the clamping pressure applied to the power transmitting member in accordance with a previous state of increase of the clamping pressure that was stored in the memory in a previous period of operation of the vehicle.

Control apparatus and method of continuously variable transmission

A method and apparatus for controlling a continuously variable transmission of a motor vehicle includes a controller that controls the speed ratio of the continuously variable transmission in accordance with a predetermined shift condition. The method and apparatus perform shift control in a specific manner during an operation of an anti-lock brake system, for example, by smoothing at least one of the rotational speed of the input shaft and the rotational speed of the output shaft, reducing a rate of change in the speed ratio during down shifting, restricting upshifting of the CVT, increasing an amount of hydraulic oil delivered from an oil pump, and/or increasing belt clamping force.

Method and apparatus to control continuously variable transmission of motor vehicle

A speed change control system for a continuously variable transmission, for controlling a gear ratio by deciding an abrupt acceleration demand of a driver, to effect an abrupt speed change when it is decided that the driver demands an abrupt acceleration. The speed change control system comprises: a drive state decider for deciding that the vehicle has changed from a driven state to a drive state, when said abrupt acceleration is demanded at the driven state; and a speed change controller for controlling said continuously variable transmission to effect said abrupt speed change, after said drive state decider decides that the vehicle has changed from the driven state to the drive state.

Shift control system for continuously variable transmission

An apparatus and a method control a belt-type continuously variable transmission of a vehicle having a continuously variable speed ratio, which is a ratio of a rotation speed of an input shaft to a rotation speed of an output shaft. The speed ratio of the transmission is controlled by changing a groove width of each of the pulleys, and a belt clamping pressure applied to at least one of the pulleys to clamp the torque transfer belt also is controlled. Furthermore, the speed ratio of the transmission is set to a low-load speed ratio when it is determined that control of the belt clamping pressure has failed and the belt clamping pressure is raised to a high level. The low-load speed ratio is predetermined so that a load applied to the torque transfer belt is substantially minimized.

Control apparatus and method of belt-type continuously variable transmission

A shift control system for a continuously variable transmission, in which a road load on a vehicle is detected, the lower limit speed is set according to the detected road load, in which a target input speed, as set according to the running state of a vehicle, is restricted with the set lower limit speed, and in which the gear ratio of the continuously variable transmission is controlled so that the actual input speed may be equal to the target input speed restricted. The target input speed is restricted after the actual input speed is more than the lower limit value, when the road load is light, and said target input speed is restricted irrespective of the actual input speed when the road load is heavy.

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Toyota, Japan

Yoshiaki Yamamoto