abstract |
In the gearbox, fully described in French Patent Application No 93 13768 (18.11.93), meshing of pinions on primary and secondary shafts is activated by motor-driven selector shafts controlled by a microprocessor-based unit receiving input from the driver's shift-lever and appropriate sensors. No synchronising clutches are provided. When changing down, the controller, via a relay (87), opens (86) a throttle by-pass passage (85), the accelerator pedal (PG) being unaltered. The weakened mixture alters the exhaust gas composition (80); this is signalled by a sensor (81) to the injection controller (82). More fuel is injected (83,79). Engine and primary shaft speeds increase. The controller, monitoring engine and road speeds, engages the new gear when pinion speeds coincide. |