Abstract: An improved, torque cushioned compressor clutch supports the armature on a hard plastic molded disk, the inner edge of which closely pilots on, but is not directly attached to, a cylindrical surface of a drive shaft mounted central hub. Instead, the outer face of the disk, near the inner edge, is abutted with an axially inwardly facing shoulder, which keeps it from pulling axially off of the hub. A softer elastomer overmold adheres to both sides of the harder support disk, adhering to the hub as well, but not adhering to the interface between the disk inner edge and hub. Therefore, when the clutch engages, the disk is free to turn on the hub, at least as far as the "wind up" limit of the elastomer allows, cushioning the engagement shock. However, during operation, the close fit of the disk on the hub prevents radial whirl.

Abstract: An electromagnetic clutch assembly for an automotive air conditioning compressor is designed so that the return force, as a function of axial displacement, is better matched to the performance requirements of the system. A steel armature, which is pulled toward and into driving contact with a pulley friction disk, moves over a predetermined axial stroke comparable to the nominal axial gap between the armature and disk, plus an allowance for armature wear with time. The armature is attached to the shaft by a stamped stainless steel diaphragm which, in its free state, is concave or dished. When the energized compressor coil pulls the armature toward the disk, the diaphragm is mechanically flattened, as compared to a spring being stretched. The return force of the disk, as opposed to the return force of a stretched spring, is relatively small and flat over the desired axial stroke.