G PHYSICS
G05 CONTROLLING; REGULATING
G05D SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
13/00 Control of linear speed; Control of angular speed; Control of acceleration or deceleration, e.g. of a prime mover
G05D13/62 characterised by the use of electric means, e.g. use of a tachometric dynamo, use of a transducer converting an electric value into a displacement