Toyota Jidosha Kabushiki Kaisha

Aisin Aw Co., Ltd.

Naoto Tanaka

Shinya Toyoda

Akira Hino

Yasunari Matsui

Tadashi Tamura

Yuji Iwase

Hiroji Taniguchi

Hiroyuki Nishizawa

Masataka Osawa

Masami Sugaya

Kunio Hattori

Makoto Sawada

Naoki Moriguchi

Hiroya Fujiwara

Naoya Inoue

Kisaburo Hayakawa

Wataru Matsubara

Shun Minaki

Munenori Terada

Masanobu Kimura

Takemichi Isono

Shuzo Sanda

A control device that controls a vehicle transmission device including an input drivingly coupled to an internal combustion engine, an output drivingly coupled to wheels, a shift input drivingly coupled to the input via a fluid coupling having a lock-up clutch, and a speed change mechanism disposed on a power transmission path connecting the shift input and the output, wherein the speed change mechanism is capable of performing both continuously variable shifting that continuously changes a speed ratio, and stepped shifting that changes a speed ratio in a stepwise manner, the control device including: an electronic control unit that is configured to perform, when the stepped shifting is performed, rotation maintained engagement control that controls an engagement pressure of the lock-up clutch such that a rotational speed of the input follows a predetermined target rotational speed, regardless of a change in rotational speed of the shift input.

Control device

Vehicle control device of vehicle including lockup clutch configured to directly couple between input/output rotating members of fluid power transmission device transmitting power of engine to automatic transmission, vehicle control device engaging lockup clutch when running state of vehicle in predetermined running state, vehicle control device providing lockup clutch pressure learning control of learning oil pressure of lockup clutch used in start-time lockup slip control in which lockup clutch placed in slip-engaged state toward engaged state at start of vehicle based on rotation speed of engine at time of engagement of lockup clutch, vehicle control device inhibiting engagement of lockup clutch when running state of vehicle in predetermined running state and also in second predetermined running state, vehicle control device engaging lockup clutch after running state of vehicle goes out of second predetermined running state, and providing lockup clutch pressure learning control in engaging process of lockup clutch.

Vehicle control device

In a controller for a belt-type continuously variable transmission including a hydraulic actuator that changes a groove width of a primary pulley, a hydraulic actuator that changes a groove width of a secondary pulley, and a belt clamping pressure control solenoid that controls the hydraulic pressure supplied to the hydraulic actuator of the secondary pulley, a mechanism calculates a transmission ratio between the primary pulley and the secondary pulley and determines whether or not there is belt slippage based on that calculated transmission ratio, and a mechanism determines normalcy of the belt clamping pressure control solenoid. The input torque when belt slippage has actually occurred, i.e., when a failure has been determined, is used as a condition when performing the normalcy determination. By setting such a condition, it is possible for a normalcy determination threshold value (input torque value &#x3b1;) used for the normalcy determination to be a small value, and thus it is possible to suppress erroneous normalcy determination.

Controller for automatic transmission

A diagnostic apparatus and a diagnostic method are provided for a belt squeezing force adjusting mechanism of a continuously variable transmission in which a belt is wound around a primary sheave that receives driving force and a secondary sheave that outputs force to a drive line, and which continuously changes the output rotation speed by adjusting the width of the groove the primary sheave and the secondary sheave by shift control. This diagnostic determines, as a precondition, whether a target control value calculated in shift control is in a low region, and performs a diagnostic on the belt squeezing force adjusting mechanism based on the relationship between an actual control value and the target control value during control to reduce a control value when it is determined that the precondition is satisfied. According to this diagnostic apparatus and diagnostic method, an erroneous diagnosis can be prevented so the diagnostic can be performed accurately.

Diagnostic apparatus and diagnostic method for belt squeezing force adjusting mechanism

A controller for a vehicle continuously variable transmission is disclosed. When a target gear ratio is set as the maximum gear ratio and a vehicle speed is decreased to less than a first reference vehicle speed, the controller suspends varying of the gear ratio by the transmission control and starts a gear ratio hold control that releases operational oil from a first oil pressure chamber and holds the gear ratio at the maximum gear ratio. Further, the controller ends the gear ratio hold control and delivers operational oil to the first oil pressure chamber when the vehicle speed increases to a second reference vehicle speed or greater, which is lower than the first reference vehicle speed, and restarts the varying of the gear ratio by the transmission control when the vehicle speed subsequently increases to the first reference speed or greater.

Controller for vehicle continuously variable transmission

An ECU executes a program including the steps of determining that a change speed solenoid is abnormal when a target speed ratio falls within a predetermined range, an upshift is recognized and the change speed solenoid is abnormal; determining that the change speed solenoid is normal when the change speed solenoid is not abnormal; determining that a belt pinch pressure solenoid is abnormal when the target speed ratio is substantially equal to a speed ratio &#x3b3;min on a maximum speed-increase side and the target speed ratio is not substantially equal to an actual speed ratio; and determining that the belt pinch pressure solenoid is normal when the target speed ratio is substantially equal to the actual speed ratio.

Failure determining device and failure determining method of continuously variable transmission

A discharge capacity reduction device that, while neutral control is performed, reduces the discharge capacity of an oil pump that is driven by the engine is provided, so that the load applied to the oil pump is reduced. Thus, the load applied to the engine is reduced and it is possible to further reduce the engine output, so that it is possible to further improve fuel economy.

Controller for vehicle power transmission apparatus

The invention provides a shift control apparatus of a continuously variable transmission, which includes a feedback control portion which executes feedback control that brings an actual speed ratio close or equal to a target speed ratio, and a normal operation determining portion which determines whether the shift control apparatus is operating normally based on a difference between the actual speed ratio and the target speed ratio, and an amount of change in the actual speed ratio and an amount of change in the target speed ratio during a predetermined interval.

Shift control apparatus of a continuously variable transmission and method of determining whether shift control apparatus is operating normally

A maximum flow calculating unit calculates a maximum amount of hydraulic fluid that can flow into or out of an input-side hydraulic cylinder when a shift control command signal is set to a reference DUTY value, based on an estimated valve pressure difference calculated by an estimated pressure difference calculating unit, and a post-guard target sheave position setting unit performs a guard process for restricting the amount of change of the sheave position, using a guard value calculated by a guard value calculating unit based on the maximum flow amount, so as to set a post-guard target sheave position. Since the thus set target sheave position does not undergo excessive large changes nor excessively small changes during shifting, a target value for shifting is set so that a feedforward controlled variable determined based on the amount of change of the target sheave position becomes an appropriate value.

Shift control system and shift control method for continuously variable transmission

A controller determines a target gear ratio from an accelerator opening and a vehicle speed. The controller determines the stroke of a trunnion on the basis of the difference between present inclination and a target inclination, thereby to control stroke by a hydraulic control valve. The stroke is corrected according to input/output disc pushing force.

Growing community of inventors

Okazaki, Japan

Naoto Tanaka