Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Jatco Corporation

Koyo Seiko Kabushiki Kaisha

Mitsubishi Jukogyo Kabushiki Kaisha

Koyo Seiko Company, Ltd.

Mitsubishi Jidosha Kogyo K.k.

Nippon Jidosha Eng. Kabushiki Kaisha

Takeo Hiramatsu

Bonnosuke Takamiya

Yoshimasa Nagayoshi

Kenjiro Fujita

Yuichi Tanaka

Yoshiaki Hamasaki

Katsutoshi Usuki

Takeo Shimizu

Satoshi Kawai

Hiroshi Fukuchi

Tetsuo Ozaki

Seiichiro Takahashi

Shuzo Hirakushi

Tsunefumi Niiyama

Kazuo Oguri

Katsuhiro Hatta

Naoki Kobayashi

Yasuhiko Fujita

Kazuaki Aota

Yasushi Yabe

Jonggap Kim

Hisaji Nakamura

Yoshihiro Kono

Haruaki Yoneda

Katuhiro Hatta

Takashi Fujioka

An automatic transmission includes a first planetary gear set; a second planetary gear set; a third planetary gear set; an input shaft; an output shaft; and five friction elements. A first ring gear is constantly locked. A third carrier is connected with a second ring gear to define a rotating member. The input shaft is constantly connected with a second carrier, and the output shaft is constantly connected with the rotating member. The five friction elements are adapted to selectively connect among the carriers, ring gears and sun gears. Each of at least seven forward speed-ratios and one reverse speed-ratio is achieved by an engaged state of two friction elements selected from the five friction elements.

Automatic transmission

An automatic transmission includes a first planetary gear set including first to third rotating elements; a second planetary gear set including fourth to sixth rotating elements; a third planetary gear set including seventh to sixth to ninth rotating elements; an input shaft constantly connected with the first rotating element; an output shaft constantly connected with the second rotating element; and at least five friction elements including a first friction element capable of locking a rotation of the eighth rotating element, a second friction element configured to selectively connect the second rotating element with the fifth rotating element, a third friction element configured to selectively connect the second rotating element with a second rotating member defined by the sixth and seventh rotating elements, a fourth friction element configured to selectively connect the fifth rotating element with the eighth rotating element, and a fifth friction element configured to selectively connect the first rotating element with the fifth rotating element. The automatic transmission achieves each of at least seven forward speed-ratios and one reverse speed-ratio, by a concurrent engagement of two friction elements which are selected from the five friction elements.

An automatic transmission includes a first planetary gear set; a second planetary gear set; a third planetary gear set; an input shaft; an output shaft; and five friction elements. A first ring gear is constantly locked. A third carrier is connected with a second ring gear to define a rotating member. The input shaft is constantly connected with a second carrier, and the output shaft is constantly connected with the rotating member. The five friction elements include a first friction element adapted to selectively connect a first carrier with a third ring gear; a second friction element adapted to selectively connect a first sun gear with the second carrier; a third friction element adapted to selectively connect the first sun gear with a second sun gear; a fourth friction element adapted to selectively connect the first carrier with the second carrier; and a fifth friction element adapted to selectively connect the first carrier with the second sun gear. Each of at least seven forward speed-ratios and one reverse speed-ratio is achieved by an engaged state of two friction elements selected from the five friction elements.

An automatic transmission includes a first planetary gear set; a second planetary gear set; a third planetary gear set; an input shaft; an output shaft; and five friction elements. The five friction elements include a first friction element adapted to selectively connect a first ring gear with a second carrier, a second friction element adapted to selectively connect the first ring gear with the second rotating member, a third friction element adapted to selectively connect the second carrier with a third ring gear, a fourth friction element adapted to selectively stop a rotation of the third ring gear, and a fifth friction element adapted to selectively connect the first sun gear with the second carrier. Each of at least seven forward speed-ratios and one reverse speed-ratio is achieved by an engaged state of two friction elements selected from the five friction elements.

An automatic transmission includes a first planetary gear set; a second planetary gear set; a third planetary gear set; an input shaft; an output shaft; and five friction elements. A first ring gear is constantly locked. A third sun gear is connected with a first sun gear to define a first rotating member, and a second sun gear is connected with a first carrier to define a second rotating member. The input shaft is constantly connected with the first rotating member, and the output shaft is constantly connected with a third carrier. The five friction elements include a first friction element adapted to selectively connect a second ring gear with a third ring gear, a second friction element adapted to stop a rotation of a second carrier, a third friction element adapted to selectively connect the second carrier with the third ring gear, a fourth friction element adapted to selectively connect the second ring gear with the third carrier, and a fifth friction element adapted to selectively connect the first rotating member with the second carrier. Each of at least seven forward speed-ratios and one reverse speed-ratio is achieved by an engaged state of two friction elements selected from the five friction elements.

An automatic transmission is provided with three planetary gear units and five friction elements that establish at least six forward speeds and one reverse speed by engaging different combinations of three out of five friction elements simultaneously. In the automatic transmission, an output shaft is always connected to a first ring gear of the first planetary gear unit. A second ring gear of the second planetary gear unit is always fixed. A first carrier of the first planetary gear unit and a third ring gear of the third planetary gear unit are connected together to form a first rotating member. A second sun gear of the second planetary gear unit and a third carrier of the third planetary gear unit are connected together to form a second rotating member.

An automatic transmission is provided with three planetary gear units and five friction elements. The first planetary gear unit includes a first sun gear that is always fixed, a first carrier supporting a first pinion in meshed engagement with the first sun gear and a first ring gear in meshed engagement with the first pinion. The first to fifth friction elements are operatively arranged with respect to the first, second and third planetary gear units to selectively establish at least seven forward speeds and one reverse speed by combining simultaneous engagement of two out of five friction elements for transmitting torque from the input shaft to the output shaft.

An automatic transmission includes a first planetary gear set; a second planetary gear set; a third planetary gear set; and at least five friction elements. The at least five friction elements includes a first clutch adapted to selectively connect a first carrier with a second carrier; a first brake adapted to selectively stop a rotation of the second carrier; a second brake adapted to selectively stop a rotation of a rotating member having a first sun gear, a second ring gear, and a third carrier; a third brake adapted to selectively stop a rotation of a third sun gear; and a second clutch adapted to selectively connect the first carrier with a second sun gear. Each of at least seven forward speed-ratios and one reverse speed-ratio is achieved by engaging two friction elements selected from the first and second clutches and the first to third brakes.

A double piston and belt type continuously variable transmission comprises a primary pulley provided with a primary piston chamber and a primary clamp chamber; a secondary pulley provided with a secondary piston chamber and a secondary clamp chamber; and an endless belt operatively put around the primary and secondary pulleys. A switching circuit is arranged to connect both the primary and secondary clamp chambers to either one of the primary and secondary piston chambers, which shows a higher hydraulic pressure than the other.

Double piston and belt type continuously variable transmission

In a shift control method, when a speed ratio of an automatic transmission is shifted from a third speed ratio to a first speed ratio before stoppage of a vehicle, a down shift line 3-1 in a shift pattern is shifted to a high-speed side to initiate shifting under a power-OFF condition. A third brake is released by setting the duty ratio of an electromagnetic valve of the third brake at 0% to establish a free condition (neutral condition) in an output shaft of a second transmission. While the duty ratio of an electromagnetic valve of a second clutch in a first transmission mechanism is set at 0%, the duty ratio of an electromagnetic valve of a second brake is gradually increased, so that the shifting from the second clutch to the second brake is made, and the first transmission mechanism is operatively shifted from the third speed ratio to a speed ratio corresponding to the first speed ratio. Then, the third brake is engaged again upon completion of the shifting and after mechanical engagement of a one-way clutch. Consequently, it is possible to reduce shocks in shifting the speed of the vehicle.

Shift control method for automatic transmission and apparatus thereof

A speed change control and apparatus of an automotive automatic transmission causes a turbine rotational speed to change toward a synchronous rotational speed associated with a desired gear stage by engaging a connection-side clutch while disengaging a release-side clutch, to thereby carry out gear-changing. To reduce a speed change shock, a speed change time is rendered stabilized irrespective of vehicle running state, by carrying out feedback control such that the time-dependent change rate (Ns)' of a rotational speed difference between clutch plates and clutch discs of the connection-side clutch becomes equal to a target slip rotational speed change rate (Ni)'.

Speed change control apparatus and method of an automotive automatic

In an automatic transmission gear system which selectively actuates a plurality of frictional elements by oil pressure such as clutches and brakes that are provided in the transmission gear system in order to obtain different gear ratios, one frictional element is disengaged concurrently with engaging of another frictional element for switching the gear ratio (speed change). At that time, it is important to adjust the timing for actuating the frictional elements depending on the conditions of the engine and the vehicle itself. The present invention relates to a control device for an automatic transmission gear system which assures smooth gear shifting at all times by adequately controlling the overlap of the torque capacities of the frictional elements.

Control device for automatic transmission gear system

A power transmission apparatus suitable for use with a four wheel drive apparatus of an automobile which can prevent production of rattling noises of a driving system and occurrence of a swerving phenomenon of the automobile. The apparatus includes a cam ring connected to a first rotary shaft and a rotor connected to a second rotary shaft and accommodated for rotation in the cam ring to define a pump chamber therebetween and is designed to transmit driving force between the first and second rotary shafts in accordance with a pressure of working fluid in the pump chamber which is produced in response to rotation of the first and second rotary shafts relative to each other. The apparatus comprises a frictional force applying mechanism interposed between the first and second rotary shafts for applying predetermined frictional force between them to assure stabilized transmission of torque between the first and second rotary shaft.

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Nagaokakyo, Japan

Takeo Hiramatsu