Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kabushiki Kaisha

Masaaki Takamatsu

Yutaka Ishikawa

Toshiyuki Suzuki

Yusuke Yoshimura

Akio Muto

Osahide Miyamoto

Hideki Wakamatsu

Yoshiharu Saitou

Masato Shigenaga

Masahide Saito

Yasuhiro Ijichi

Takafumi Sakai

Shinya Abe

Tadahiro Suzuki

Kenichi Haraguchi

In an apparatus for controlling an automatic transmission connected to a prime mover mounted on a vehicle, having a torque converter equipped with a lock-up clutch, when the automatic transmission is gear-shifted to a predetermined gear at deceleration of the vehicle and it is determined that predetermined operating conditions of the vehicle are satisfied, a lock-up clutch engaging circuit is formed through a hydraulic supply circuit. Next it is determined whether engage-position sticking malfunction of the lock-up clutch has occurred based on a ratio of an input rotational speed of the automatic transmission relative to an output rotational speed of the prime mover when the lock-up clutch engaging circuit has been formed, and fail-safe control is then implement when the sticking is determined.

Control apparatus for automatic transmission

A control device for controlling an engagement state of a lock-up clutch is provided. A plurality of target slip ratio maps include a normal slip ratio map having a characteristic line of a target slip ratio defined in accordance with an engine load at a normal vehicle running condition and a modified slip ratio map having a characteristic line of the target slip ratio to become a facing calorific value lower than a facing calorific value corresponding to the slip ratio retrieved from the normal slip ratio map. In the case where an estimate value of the facing temperature continues to exceed first threshold temperature for more than predetermined time when to carry out slip control using the normal slip ratio map, control to switch the target slip ratio map from the normal slip ratio map to the modified slip ratio map is carried out.

Control device of lock-up clutch

A lock-up control apparatus includes a kick-down instruction detector configured to detect a kick-down shift transmission instruction during application of a lock-up clutch. A first lock-up control amount changer is configured to change the lock-up control amount when the kick-down shift transmission instruction is detected. An intermediate gear speed determinator is configured to determine whether the kick-down shift transmission instruction includes an intermediate gear speed shift transmission instruction to an intermediate shift transmission gear speed. A second lock-up control amount changer is configured to change the lock-up control amount when the kick-down shift transmission instruction includes the intermediate gear speed shift transmission instruction. A target gear speed shift transmission instruction detector is configured to detect a target gear speed shift transmission instruction. The third lock-up control amount changer is configured to change the lock-up control amount when the target gear speed shift transmission instruction is detected.

Lock-up control apparatus for automatic transmission

A control device for an automatic transmission having a torque converter with a lock-up clutch provided between an engine and the automatic transmission, and a lock-up control device for controlling an engaged condition of the lock-up clutch. The control device includes a plurality of different target slip ratio maps each having a plurality of target slip ratio characteristic lines of the lock-up clutch predetermined according to a throttle angle, a first map selector for selecting one of the target slip ratio maps according to a running range, according to whether the running road is a level road/downhill road or an uphill road, and according to a gear position during running in the condition where an accelerator pedal is depressed, and a second map selector for selecting one of the target slip ratio maps according to a running range, according to whether the running road is a level road/uphill road or a downhill road, and according to a gear position during running in the condition where the accelerator pedal is undepressed.

Control device for automatic transmission

In a control apparatus for a hydraulically operated vehicular transmission, the hydraulic pressure of a hydraulic clutch on the engaging side which is engaged at the time of speed changing (engaging pressure) is detected by a hydraulic pressure sensor. When the detected value of the engaging pressure has exceeded a predetermined value, the hydraulic pressure of a hydraulic clutch on the disengaging side to be disengaged at the time of speed changing (disengaging pressure) is reduced to a predetermined low pressure. Even if the detected value of the engaging pressure has exceeded a predetermined value YPC, the decrease in the disengaging pressure down to a predetermined low pressure QUPOFFB is delayed by a predetermined time YTMUP9 at the time of low oil temperature when the detected value of an oil temperature to be detected by an oil temperature sensor is below a predetermined value YTO. When a discrimination is made as to whether the detected value of the engaging pressure PC(N+1) has exceeded the predetermined value YPC from a predetermined time after the start of the speed changing, the time to start the discrimination may be delayed by a predetermined time at the time of low oil temperature.

Transmission controller responsive to low oil temperature to delay the

A control apparatus for a hydraulically operated vehicular transmission having a plurality of hydraulic engaging elements has an accumulator which is connected in parallel with a hydraulic engaging element for a low-speed transmission train and a back pressure generating source which generates a hydraulic oil pressure to be supplied to a back pressure chamber of the accumulator. The control apparatus includes a changeover valve which can be changed over between a first position in which the back pressure chamber of the accumulator and the back pressure generating source are brought into communication with each other and a second position in which the communication is cut off to lower a pressure in the back pressure chamber. The changeover valve is arranged to be changed over from the second position to the first position when a hydraulic oil pressure in the hydraulic engaging element for the low-speed transmission train has exceeded a predetermined pressure.

Hydraulic bypass to back pressure chamber of a clutch accumulator

Growing community of inventors

Wako, Japan

Masaaki Takamatsu