Armature assembly for an electromagnetic coupling

An armature disc 51 is attached to a resilient plastic spider 40 by angularly spaced rivets 60. To prevent the spider 40 from striking the disc 51 and creating a buzzing noise, spacer pads 71 are formed integrally with the spider 40 adjacent the rivets 60 and establish an axial gap 70 of substantial width between the disc 51 and the spider 40 along acrs located between the rivets 60. The heads 62 of the rivets 60 are located in countersunk holes 80 in the spider 40 and pull axially through the plastic of the spider 40 to release the armature disc 51 from the spider 40 if the spider 40 becomes excessively hot as a result of slippage of the coupling. A metal washer 85 on the hub 36 of the coupling prevents the hot disc 51, when released, from dropping onto and melting a central sleeve portion 41 of the spider 40.