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Mechanical Function, Overview

Fig 1: Coupling Multi-Plate Clutch Pack
GLL107824Courtesy of VOLVO CARS CORPORATION
1 Cam disc with sinusoidal cam curve 7 Hub with sinusoidal cam curve
2 Rollers for the annular piston 8 Housing for the outer plates
3 Rollers for the operating piston 9 Outer plates
4 Annular piston 10 Inner plates
5 Operating piston 11 Pressure springs
6 Input shaft 12 Output shaft.

The transmission and bevel gear transfers engine torque to the propeller shaft. The input shaft is joined to the clutch's output shaft via the multi-plate clutch pack. The multi-plate clutch in the coupling must be engaged to transfer torque to the rear axle. The inner and outer wet multi-plate clutch are the transfer point between the input and output shafts.

The sinusoidal cam disc with its sinusoidal curve rotates at the same speed as the propeller shaft. The annular piston rollers act on the cam disc's cam curve and press the annular pistons in and out. This creates an oil flow. The oil flow is controlled by the control valve/axial solenoid to create an oil pressure. The oil pressure affects the operating pistons that are applied against the multi-plate clutch pack.