Aisin-warner Kabushiki Kaisha

Aisin Aw Co., Ltd.

Hideyuki Aoki

Masakatsu Miura

Yoichi Hayakawa

Masahiko Ando

Akira Fukatsu

Kozo Kato

Atsushi Mori

Hiroyuki Tsukamoto

Akira Matsuo

Hideaki Furuta

A hydraulic power transmission is provided with a frictional engagement element as a lock-up clutch between a hydraulic power transmission chamber, housing a pump impeller and a turbine runner, and a servo oil chamber of the lock-up clutch. A lock-up oil passage that supplies lock-up hydraulic pressure to the servo oil chamber is connected to a hydraulic pressure supply circuit that is used in common with a circulation oil passage that supplies hydraulic pressure for circulation to the hydraulic power transmission chamber. An orifice is disposed in the circulation oil passage. It is thus possible to perform lock-up with different supply pressures. A common oil supply for the lock-up oil passage and the circulation oil passage is provided, for example, by disposing a converting circuit that adapts an oil passage connection to hydraulic transmissions with different types of lock-up clutches.

Hydraulic circuit and hydraulic control unit for hydraulic power transmission

A double-acting hydraulic actuator structure for use in an automatic transmission has a two-layered structure which includes first and second frictional engagement element hydraulic actuators. The first hydraulic actuator includes a drum member and a first piston fitted hermetically and slidably in the drum member. The second hydraulic actuator is formed by the interior of the first piston and a second piston fitted hermetically and slidably mounted within the first piston. The first and second pistons are both urged toward their disengaged positions by the action of a common return spring. A second spring is provided for urging the second piston alone against the force of the return spring.

Hydraulic actuator in automatic transmission

Automatic transmission including a main-transmission-mechanism consisting of two planetary gear units (three speed or four speed transmission mechanism for example) and a sub-transmission-mechanism consisting of one planetary gear unit (underdrive mechanism, for example). One speed and two speed for the whole transmission are obtained, with a low speed stage of the main-transmission-mechanism lower than two speed, by shifting the main-transmission-mechanism to one and two speed, respectively, while the sub-transmission-mechanism is kept at low speed (underdrive). And three speed for the whole transmission is obtained by shifting the sub-transmission-mechanism to high speed (direct coupling) while the main-transmission-mechanism is left at the two speed state. Further, four speed or five speed for the whole is obtained by shifting the main-transmission-mechanism to three speed or, if it is of four speed type, to four speed, respectively, while the sub-transmission-mechanism is kept at the high speed state.

Automatic transmission

In an automatic transmission including a torque converter, the transmission mechanism is capable of performing lock-up function. The input side portion of a first clutch is coupled with the turbine of the torque converter, wherein the first clutch is in connection while the automatic transmission mechanism is in forward one, forward two and forward three speed, respectively. The input side portion of a third clutch is coupled with the impeller of the torque converter, wherein the third clutch is in cut-off during forward one and two speed and in connection during high speed stages (three speed and four speed, for instance). Thus, in low speed states (one speed and two speed), the torque is transferred through the oil flow of the torque converter, and in high speed states (three speed and four speed), the torque which is machanically coupled with the engine output shaft is transfered to the automatic transmission mechanism.

A plurality of clutches are disposed at one place in the automatic transmission of the present invention to form a clutch portion, the clutch portion is disposed at a front end portion of the automatic transmission mechanism portion, an annexed transmission part is disposed at a position adjacent to the automatic transmission mechanism portion, and the annexed transmission part is provided with a counter gear which is actuated by an output member of the automatic transmission mechanism portion and is detachably attached with a sub-transmission unit. When the transmission is assembled, a multitransmission stage can be obtained by modifying the clutch portion, and attaching/detaching the sub-transmission unit.

Sun gears of a single planetary gear unit and a dual planetary gear unit are connected with respect to each other, carriers of the respective gear units in the connected state are connected to an output member, an input member is connected to a ring gear of the single planetary gear unit through a first clutch and also to a sun gear through a second clutch, and the sun gear and a ring gear of the dual planetary gear unit are stoppable by retaining means. When travelling forward, the ring gear of the single planetary gear unit is inputted with torque from the input member based on the state of connection of the first clutch.

Automatic transmission mechanism

Sun gears of a single planetary gear unit and a dual planetary gear unit are connected with respect to each other, carriers of the respective gear units in the connected state are connected to an output member, an input member is connected to a ring gear of the single planetary gear unit through a first clutch, to a sun gear through a second clutch and also to a ring gear of the dual planetary gear unit through a third clutch, and the sun gear and a ring gear of the dual planetary gear unit are stoppable by retaining means. When in forward travelling, the ring gear of the single or dual planetary gear unit is inputted with torque from the input member based on connection of the first and/or third clutch.

Growing community of inventors

Anjo, Japan

Hideyuki Aoki