Valeoscope Commercial Vehicles Clutch 2020

Valeo clutch and actuation for heavy duty

Push-type cover assembly On a push type cover assembly, the release bearing pushes the diaphragm toward the flywheel, to disengage the clutch. Pull-type cover assembly On a pull type cover assembly, the release bearing pulls the diaphragm away from the flywheel, through a connection system. The difference between the two technologies is the position of the articulation of the diaphragm inside the cover. This means that the lever arm between the diaphragm articulation and the release bearing contact on the diaphragm is longer in case of pull- type cover assembly than in case of push-type.

So, for a pull-type cover assembly, the release bearing effort will be lower up to 30% compared to push-type design. Therefore, for the same release bearing effort, the clamp load of the clutch can be increased by 30%. To summarize, the pull type system benefits are:

The advantages of the Valeo Self Adjusting Technology are: ●● High torque capacity ●● Compact and robust design ●● Reliable: compact design as the S.A.T. device is integrated in the clutch cover. Axial compactness due to increased release travel. ●● Easy to fit: Valeo S.A.T. does not require special tools for installation. It can be installed using standard garage equipment. ●● Comfortable: constant diaphragm spring position, constant release bearing effort.

●● Lower release bearing effort ●● Cover deformation reduced ●● Reduction of pressure plate lifts loss

Test on Cover

●● Durability test ●● Performance test clamp load and release effort ●● Burst strength ●● Vehicle fitting test

Gearbox side

Diaphragm articulation

Self Adjusting Technology (S.A.T.) A development of the modern clutch is the self adjusting system, which ensures the same diaphragm finger height throughout the whole life of the clutch, maintaining limited and constant release bearing effort and, limited impact on the crankshaft of the engine. Self Adjusting technology working principle The facings wear is compensated by the cover assembly through a fulcrum with ramps which can rotate, allowing a modification of the pressure plate height. This incremental actuation is done by an operating spring which manoeuvers a screw and ratchet wheel fixed on the fulcrum with ramps at each clutch engagement. This operation is activated at each clutch disengagement and as soon as a certain level of facings wear is reached, the ratchet wheel can rotate to jump to the next teeth and modify the pressure plate height through the fulcrum. The position of the diaphragm remains always the same, allowing a constant release bearing effort.

Release bearing

Flywheel side

Pressure plate

Push-type diaphragm

Gearbox side

Release bearing

Diaphragm articulation

Flywheel side

Pressure plate

Pull-type diaphragm

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