DEVICE FOR DETECTING THE ROTATION AND/OR FOR MEASURING THE ROTATION SPEED OF A SMALL DC MOTOR WITH PERMANENT OR ELECTRO-MAGNETS

摘要

1. A rotary recognition and/or rotational speed detecting device in a permanent magnetically excited direct-current fractional horsepower motor with magnetic segments (12, 13) distributed along the bore circumference of the stator with pole gaps left free on the inner circumferential face of a stator housing (11) and with a rotor (2) grooved and/or toothed along its circumference as well as with at least one measuring coil (4) able to be induced by the groove-frequent pulsation of the stray field when rotating the rotor (2) and arranged in a pole gap between the magnetic segments (12, 13) on a carrying body (3), characterised in that the measuring coil (4) is arranged in a non-magnetic plastic carrying body (3) axially introduced and held between the magnetic segments (12, 13), and the plastic carrying body (3) is provided with at least one axial guidance groove (35) and the motor housing (11) is provided with at least one corresponding axial guiding cam (111).