Electromagnetic brake structure

1. An electromagnetic brake structure comprising:

a coil seat including a plurality of receiving holes disposed on a front end thereof to receive a number of compression springs respectively and an electromagnetic coil mounted on the front end thereof;

a movable friction piece fitted on the front end of the coil seat;

a brake member fixed in a front end of the friction piece and including a transmitting shaft fitted thereon to actuate with the brake member;

a fixed member secured on a front end of the brake member and locked with the coil seat, wherein

the electromagnetic coil includes a first silicon steel ring, a plurality of slots arranged around a peripheral side of the first silicon steel ring, a number of elongate grooves radially extending along an outer side of the first silicon steel ring and communicating with the slots respectively, and each slot includes an isolation holder fitted therein, and the isolation holder includes a recess formed on one side thereof to correspond to the groove of the first silicon steel ring, and between two isolation holders is provided with a coil set formed by an enameled copper wire; and

the friction piece includes a notch defined at a position thereof and corresponding to the first silicon steel ring of the electromagnetic coil so as to receive a second steel ring for matching with the coil set.