Patent ID: 6878086
Filing Date: 2005-04-12
Classification: F16H

Abstract:
1. An automatic transmission for changing a torque transfer path through a gear section, to thereby change rotational speed of an input member to one of a plurality of shift speeds, and transmitting the rotation at the one shift speed to an output member using a clutch and a holding unit, said automatic transmission having axially opposed front and rear ends defining front and rear end sides for components of the automatic transmission, said automatic transmission comprising: at least a first clutch, a second clutch and a third clutch which transmit the rotation of the input member to different rotational elements of the gear section, and which are engaged when moving forward and are positioned together with a first oil pressure actuator, a second oil pressure actuator, and a third oil pressure actuator, respectively, to form a clutch section; wherein the second and third clutches are axially aligned so that the rear end side of the second clutch and the front end side of the third clutch oppose each other, and the first clutch is located radially inside the second and third clutches; wherein a clutch drum is axially extended to accommodate both the second and third clutches, and wherein by engaging and disengaging the second clutch from the front end side using a second piston of the second oil pressure actuator, and by engaging and disengaging the third clutch from the rear end side using a third piston of the third oil pressure actuator, the first, second and third clutches are separately engaged and disengaged by the first, second and third oil pressure actuators, respectively; and wherein the clutch drum has a flange on the front end side which is sandwiched between the second piston of the second oil pressure actuator and the third piston of the third oil pressure actuator, and wherein the third piston of the third oil pressure actuator has a portion extending axially toward the rear end alone an external surface of said drum to a portion for engaging the third clutch from its rear end side.