Combustion engine output limitation at max permitted road speed - using two independent indications of road speed as precaution against illegal manipulation

摘要

The admissible ranges (unshaded on the diagram) of the ratio of the engine speed in rev/min to road speed in km/h for six forward gears and one reverse gear are stored in the memory of the controller which sets the max. power output. One of the road speed signals may be derived from the rotational speed of the rear axle. The other may be deduced from the output shaft speed of the electronically controlled automatic transmission with allowance for rear axle ratio and tyre circumference. ADVANTAGE - Possibility of raising limit by manipulation of either of independent road speed signals is avoided.