Abstract: An engine position transducer device includes first and second discs adapted to be coupled to a rotary part of an engine. The first disc has a plurality of vanes equal in number to the number of engine cylinders. The leading edges of the vanes are equi-angularly spaced about the axis of the disc but the trailing edges are arranged so that each vane has a different length. The disc has a larger number of equally spaced marks 14. Transducers are associated with the discs and a signal processing device is provided which counts the number of marks on the second disc which pass the associated transducer while a vane on the first disc is passing the associated disc. The processing device contains stored information and can compare the count values with the stored information to provide a recognition signal. In addition the processing device is able to determine whether or not the engine is rotating in the correct direction.

Abstract: A transmission system comprises an engine (10) which drives a propeller shaft (14) through continuously variable gearing (CVG) (11), split path gearing (12), and a disconnector device (13). The gear ratio of the CVG (11) is controlled by an actuator (24). The input and output shaft speeds of the CVG (11) are sensed by transducers (25, 26) and the propeller shaft speed is sensed by a pair of transducers (27, 28). The system is responsive to an accelerator pedal (22) and a selector switch (23), and controls a throttle (19) via an electric motor (20).In normal operation, with the selector switch (23) in the drive position (D) or the reverse position (R), two signal generators (41, 42) calculate a target throttle position and a target engine speed and the motor (20) and actuator (24) adjust the throttle (19) and CVG (11) accordingly.When the switch (23) is in the neutral position (N) or the park position (P), the disconnector device (13) receives the drive from the propeller shaft (14). The speed (N.sub.