Automatic clutch control device

Automatic control device for a clutch (1) of a motor vehicle, said automatic control device comprising at least one proportional sensor (50) responsive to the rotation speed of an engine of a motor vehicle providing speed proportional sensor signals and a logic system (51) adapted to be coupled to a speed control device of the vehicle and adapted to produce a two-state signal including an active state corresponding to a clutch release order, operating means (2) for operating the clutch between first engaged and second disengaged positions, and control means (3, 40) controlling the operating means (2) responsive to the proportional sensor signals and to the two-state signal so that the clutch (1) is moved into the second disengaged position in response to the active state of the two-state signal and, in the absence of such active state, the clutch is moved toward the first engaged position, said operating means (2) being connected to a direct current voltage source (30) through an on/off switching device with two channels corresponding to movement toward the first engaged and second disengaged positions, respectively, and said control means comprising a logic processor (40) defining means for algebraically deriving an acceleration signal from said speed proportional sensor signal, means for comparing said derived acceleration signal with a predetermined threshold acceleration signal to provide a logic signal depending on whether said derived signal is higher or lower than said predetermined threshold acceleration signal, and means for enabling the first or second channel of said switching device as a function of said logic signal for recurring periods of fixed duration, at a recurrence frequency which is a selected function of the speed proportional sensor signal.