Patent ID: 6863635
Filing Date: 2005-03-08
Classification: F16H

Abstract:
1. A speed change mechanism of an automatic transmission, comprising: a first planetary gear unit which includes a sun gear, a rotation input member and a rotation output member, the first planetary gear unit outputting a reduced speed rotation from the rotation output member upon receiving a rotation from a prime mover by the rotation input member; a speed change unit to which the reduced speed rotation is applied from the rotation output member of the first planetary gear unit, the speed change unit being arranged at an opposite position of the prime mover with respect to the first planetary gear unit; an oil pump arranged between the first planetary gear unit and the prime mover and driven by the prime mover, the oil pump including a case to which the sun gear of the first planetary gear unit is connected; friction elements which selectively engage and disengage the rotation input and output members of the first planetary gear unit and rotation members of the speed change unit for achieving a desired speed position; and a direct clutch arranged to directly transmit the rotation from the prime mover to the speed change unit, the direct clutch including an annular clutch pack which is concentrically disposed around the first planetary gear unit and a clutch piston which is arranged at an opposite position of the oil pump with respect to the first planetary gear unit for actuating the annular clutch pack.