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Main Component Elements




STRUCTURE AND OPERATION

TRANSAXLE : Main Component Elements


TORQUE CONVERTER (WITH LOCK-UP FUNCTION)

Revision: March 20122013 Infiniti JX
In the same way as a conventional A/T, the torque converter is a system that increases the engine torque and transmits the torque to the transaxle. A symmetrical 3-element, 1-stage, 2-phase type is used here.

OIL PUMP

The adoption of a trochoidal oil pump with a flow control valve actuated directly by the engine enables the sufficient discharge from an oil pump in the low-rpm range and the adequate discharge adjustments in the high rpm range. Discharged oil from oil pump is transmitted to control valve. It is used as the oil of primary and secondary pulley operation, the oil of clutch operation, and the lubricant for each part.

PLANETARY GEAR

- A planetary gear type of forward/reverse selector mechanism is installed between the torque converter and primary pulley.
- The power from the torque converter is input via the input shaft, operating a wet multi-plate clutch by means of hydraulic pressure to switch between forward and reverse driving.
Operation of Planetary gear






BELT & PULLEY

It is composed of a pair of pulleys (the groove width is changed freely in the axial direction) and the steel belt (the steel plates are placed continuously and the belt is guided with the multilayer steel rings on both sides).
Revision: March 20122013 Infiniti JX
The groove width changes according to wrapping radius of steel belt and pulley from low status to overdrive status continuously with non-step. It is controlled with the oil pressures of primary pulley and secondary pulley.





Steel Belt





It is composed of multiple steel plates (A) and two steel rings (B)
stacked to a several number. The feature of this steel belt transmits power with compression of the steel plate in contrast with transmission of power in pulling with a rubber belt. Friction force is required with the pulley slope to transmit power from the steel plate. The force is generated with the following mechanism:
Oil pressure applies to the secondary pulley to nip the plate. --> The plate is pushed and extended outward. -->
The steel ring shows withstands. -->
Pulling force is generated on the steel ring. --> The plate of the primary pulley is nipped between the pulley. -->
Friction force is generated between the steel belt and the pulley.
Therefore, responsibilities are divided by the steel plate that transmits the power with compression and the steel ring that maintains necessary friction force. In this way, the tension of the steel ring is distributed on the entire surface and stress variation is limited, resulting in good durability.
Pulley
The primary pulley (input shaft side) and the secondary pulley (output shaft side) have the shaft with slope (fixed cone surface), movable sheave (movable cone surface that can move in the axial direction) and oil pressure chamber at the back of the movable sheave.
Revision: March 20122013 Infiniti JX
The movable sheave slides on the shaft to change the groove width of the pulley. Input signals of engine load (accelerator pedal opening), primary pulley speed and secondary pulley speed change the operation pressures of the primary pulley and the secondary pulley, and controls the pulley groove width.






FINAL DRIVE AND DIFFERENTIAL

The deceleration gears are composed of 2 stages: primary deceleration (output gear, idler gear pair) and secondary deceleration (reduction gear, final gear pair). All of these gears are helical gears.
Revision: March 20122013 Infiniti JX
The lubrication oil is the same as the fluid (Genuine NISSAN CVT Fluid NS-3) which lubricates the entire transaxle.