Device including a pulley, a clutch, a retarder, and a brake, in particular for hoisting gears

Claim 1

An eddy current coupling device, comprising: a. a rigid, generally cylindrical housing, b. a central shaft journaled for rotation in the housing, c. a double bell rigidly secured to the shaft and having a central web and cylindrical, coaxial, first and second bell skirts integral at their one endS with the web and axially aligned with the shaft, d. a retarder inductor coil rigidly secured to the housing, surrounding the shaft, and substantially completely disposed within the first bell skirt and defining an air gap therebetween, e. a driven member rotatably mounted to the shaft, f. a constant speed drive motor having an output shaft, g. means drivably coupling the output shaft to the driven member, h. a driver inductor coil rigidly secured to the driven member, rotatably secured to and surrounding the shaft, and substantially completely disposed within the second bell skirt and defining an air gap therebetween, i. slip ring means surrounding the shaft and rotatable with the driver inductor coil for delivering electrical energy thereto, and j. an electromechanical safety brake mounted to the housing and including a brake shoe adapted to bear against one of the bell skirts upon actuation.