A geared unit where the teeth inside the wheel are eccentric compared to the driving pinion. This pump turns at the same speed as the engine, aspire escape and return in the lid (dimension capacites of synchronization) of block hydraulic and drive back below of piston of clutch automatic. Its flow is proportional to the speed of the engine.

With the engine turning at 700rpm approximately, the compression of spring (t) is adjusted by its adjustment screw, so that the pressure existing in the chamber (f) (therefore in the clutch cylinder) is equal to P1 (see clutch cylinder : "Slip").

The flexibility of spring (t) is such that the clutch is totally engaged at an engine speed of 1200rpm.

Placed under the sleeve of the manual clutch piston and resting against a loaded spring (S), these chambers determine the synchronization time. According to the position of the selector valves, the high pressure fluid passing through the flow regulator comes to fill the chamber corresponding to the selected gear (fig.1); this allows a progressive rise in pressure (controlled by spring (s) in the clutch slave cylinder (see Pl.32-33)).