Rotor rotating angle limiter

A rotor rotating angle limiter consisting of a rotor (1) whose circumference is circular, a stator (3) having a concentric circular arc circumference facing said rotor with a gap having a length between them, one projection (2) having a shorter length than the gap length and also installed on the circumference of the rotor facing the stator, two projections (4a and 4b) installed on the circumference of the stator facing the rotor, having a shorter length than the gap length and arranged apart along the circumference of the stator circular arc outside of the orbit of the projection on the rotor, and a circular cylindrical roller (5) inserted within the cylindrical surface created between the rotor and stator and between the two projections on the stator and in the gap so that it can cross the orbit of the projection on the rotor and is also rotatably movable along the gap, wherein a radial space exists between the projection on the rotor and the projections on the stator so that the stator and rotor can rotate with respect to each other unless the roller comes between the projection on the rotor and one of the projections on the stator with the roller being rotated by the relative movement of the rotor and stator until the roller becomes positioned in contact between the projection on the rotor and the one projection on the stator.