ANORDNING FOR SYNKRONISERAD VEXLING AV STEGVIS INSTELLBARA VEXELLADOR FOR MOTORFORDON

摘要

An automatic gear change system for automatically actuating gear shift devices of a stepped change speed gear box of a motor-vehicle provided with a clutch means comprises a central control device; means for monitoring input and output speeds of the stepped change-speed gear box during synchronous running of input and output transmission shafts to be coupled to each other; and synchronizing aids for expediting synchronous running of the two transmission shafts. The control device includes a synchronizing circuit arrangement producing digital control signals during super-synchronous, sub-synchronous and substantially synchronous running of the two transmission shafts, and further includes switching logic means comprising digitally operating switching and gating circuits which actuate the synchronizing aids, gear shift devices and the clutch means. The synchronizing circuit arrangement advantageously uses two Schmitt triggers having different response and fallout thresholds.