Patent ID: 6916268

Claim:
A six-forward speed, one-reverse-speed automatic speed change apparatus for motor vehicles comprising: a first shaft ( 100 ) for receiving power from a prime mover via a torque converter ( 10 ); a second shaft ( 200 ) disposed in parallel with the first shaft ( 100 ) for transmitting the power therethrough; a third shaft ( 300 ) provided in parallel to the second shaft ( 200 ) for delivering the power through a differential gear ( 40 ); first and second planetary gear sets ( 20 )( 30 ) provided on the second shaft ( 200 ) and comprising first, second and third elements for receiving power and a fourth element for delivering power therethrough; first, second and third drive paths for connecting the first shaft ( 100 ) to the first, second and third elements of the first and second planetary gear sets ( 20 )( 30 ); first, second and third counter gear sets ( 1 )( 2 )( 3 ) providing the first, second and third drive paths, respectively, and each comprising two gears in mesh with each other; clutches (C 1 )(C 2 )(C 3 ) provided in the first, second and third drive paths, respectively; brakes (B 2 )(B 1 ) provided in the respective second and third drive paths for braking the respective second and third elements; a one-way clutch ( 232 ) provided in the third drive path for braking the third element only in a direction opposite to the direction of rotation thereof in which power is input; and a fourth counter gear set coupling the second shaft ( 200 ) to the third shaft ( 300 ), wherein a ring gear ( 23 ) of the first planetary gear set ( 20 ) serves as the first element having the first drive path connected thereto, wherein a planetary carrier ( 24 ) supporting planetary gears ( 22 ) in mesh with the ring gear ( 23 ) serves as the fourth element, wherein a sun gear ( 21 ) meshing with the planetary gears ( 22 ) is joined to a sun gear ( 31 ) of the second planetary gear set ( 30 ) to provide the second element having the second drive path connected thereto, wherein a planetary carrier ( 34 ) supporting planetary gears ( 32 ) in mesh with the sun gear ( 31 ) serves as the third element having the third drive path connected thereto, wherein a ring gear ( 33 ) meshing with the planetary gears ( 32 ) serves as the fourth element, wherein the planetary carrier ( 24 ) and the ring gear ( 23 ) serving as the fourth elements are joined to the second shaft ( 200 ) for transmitting power therethrough, and wherein two of the clutches (C 1 )(C 2 )(C 3 ) for controlling the first, second and third drive paths, the brakes (B 2 )(B 1 ) and the one-way clutch ( 232 ) are selectively engaged to obtain seven speeds.