ELECTROMAGNETIC CLUTCH HAVING IMPROVED CLUTCH PULL FORCE

An electromagnetic clutch device for a compressor includes a crank shaft (22) with an inner shaft end (24) accommodated in a compressor housing (12) and with an outer shaft end (26) projecting axially out of the compressor housing. A pulley assembly (14) has a rotor body and a pulley. The rotor body accommodates a coil housing (42) and is rotatably supported on the compressor housing by a pulley bearing (30). The coil housing (42) includes a radially inner annular wall (44), a radially outer annular wall (46), and a bottom (48) an axial end of the coil housing proximate the inner shaft end. An armature plate is connected to the outer shaft end (26) in an axially displaceable manner and rotates with the crank shaft (38). The outer surfaces of the inner annular wall (44) and the outer annular wall (46) of the coil housing (42) have a greater distance from one another near the bottom (48) of the coil housing (42) than proximate the axially open end.