First Gear (D Range)

First Gear (D range)

Outline
^ Driving force of the input shaft is transmitted to the rear sun gear to rotate it counterclockwise, applying force to the rear pinion gear to revolve counterclockwise. As the rear planetary carrier is integrated with the output gear, load from the vehicle (force that tries to prevent the rear planetary carrier from rotating counterclockwise) is applied and the rear pinion gear tries to rotate clockwise.
^ Though the rear internal gear tries to rotate clockwise due to the clockwise rotation effort of the rear pinion gear, the rear internal gear rotation is locked by the low one-way clutch via the low clutch. Due to this, driving force of the rear pinion gear overcomes the load from the vehicle to revolve counterclockwise while rotating clockwise, and rotates the rear planetary carrier counterclockwise.
^ Due to this, the output gear rotates counterclockwise and the driving force is transmitted to the reduction internal gear via the idler gear.
^ Though the reduction internal gear rotates clockwise, trying to revolve the reduction pinion gear clockwise, the reduction pinion gear tries to rotate clockwise as the load from the vehicle (force that prevents the reduction carrier from rotating clockwise) is applied to the reduction carrier.
^ The force of the reduction pinion gear, which tries to rotate clockwise, tries to rotate the reduction sun gear counterclockwise. However, counterclockwise rotation of the reduction sun gear is locked by the reduction one--way clutch. Due to this, driving force of the reduction pinion gear overcomes the load from the vehicle to revolve clockwise while rotating clockwise, and rotates the reduction carrier clockwise.
^ Therefore, the reduction gear also rotates clockwise and the driving force is transmitted to the driving wheels.
^ During deceleration, torque is transmitted from the driving wheels, in the opposite direction of that during acceleration. First, force is transmitted from the driving wheels via the final gear and the reduction gear to rotate the reduction carrier clockwise. Moreover, the force tries to revolve the reduction pinion gear clockwise.
^ The force to rotate the reduction pinion gear clockwise tries to rotate the reduction internal gear clockwise. However, as the load from the engine (force that tries to prevent the reduction internal gear from rotating clockwise) is applied to the reduction internal gear, the reduction pinion gear rotates counterclockwise.
^ Due to the counterclockwise rotation of the reduction pinion gear, the reduction sun gear tries to rotate clockwise. However, at this time, the reduction one-way clutch that is locked during vehicle acceleration becomes free and starts to rotate freely.
^ Due to this, the reduction pinion gear force that tries to rotate the reduction internal gear clockwise is absorbed by the free rotation of the reduction sun gear. Therefore torque is not transmitted to the reduction internal gear and the engine braking is not applied.





Operation
^ With shift solenoids A, B, and C ON, pilot pressure is applied to every bottom end of the shift valves, and each shift valve is positioned on the upper side.
^ Line pressure is applied the low clutch accumulator, and engages the low clutch through shift valve B.
^ Line pressure is applied reduction brake through shift valve B.
^ Line pressure delivered to the pressure regulator valve is sent to the torque converter through the TCC control valve as torque converter pressure.