Torque Converter
The torque converter is connected to the flywheel. It consists of an impeller (pump), turbine, stator, and torque converter clutch piston, which uses ATF to transmit engine power to the input shaft (mainshaft). Around the outside of the torque converter housing, the starter ring gear is installed, which is used to start the engine.
Lock-Up Mechanism
The lock-up causes the input shaft (mainshaft) to rotate at the same speed as the engine crankshaft by engaging the torque converter cover with the turbine by the lock-up clutch. Together with the hydraulic control, the PCM optimizes the timing and degree of lock-up. The lock-up mechanism operates in D (during accelerating: 1st, 2nd, 3rd, 4th, 5th, and 6th gears/during decelerating: 2nd, 3rd, 4th, 5th, and 6th gears), S with automatic shift mode (during accelerating: 1st, 2nd, 3rd, 4th, and 5th gears/during decelerating: 2nd, 3rd, 4th, and 5th gears), and S with sequential sportshift mode (during accelerating: 1st, 2nd, 3rd, 4th, 5th, and 6th gears/during decelerating: 2nd, 3rd, 4th, 5th, and 6th gears). The torque converter clutch is in the torque converter. The multi-plate torque converter clutch increase the torque capacity and increases the lock-up clutch suface area, improving fuel economy and durability.
Torque Converter Clutch Lock-Up ON (Engaging Torque Converter Clutch)
The fluid pressure is applied to the lock-up fluid passage (94) in the torque converter, causing the torque converter clutch in the torque converter to be engaged and then the turbine and the torque converter cover to be engaged. The mainshaft rotates at the same speed as the engine crankshaft when the torque converter clutch in the torque converter is engaged.
Scheme 1
Torque Converter Clutch Lock-Up OFF (Disengaging Torque Converter Clutch)
When the fluid pressure to the lock-up fluid passage (94) in the torque converter is blocked, the torque converter clutch in the torque converter is released. The turbine and the torque converter cover are also released at this time, causing the mainshaft and the engine crankshaft to rotate at a different speed.
