Abstract: A compact electromagnetic clutch has a toothed armature connected to a driven hub and a toothed driving hub which are moved into engagement with each other upon energization of an electromagnet. A precompressed spring disposed between the bottom of a cylindrical cup attached to the armature and the head of a pin attached to the driven hub biases the armature away from the driving hub. The precompressed spring provides a force strong enough to overcome residual magnetism. The spring is further compressed when the armature moves into engagement with the driving hub upon energization of the electromagnet. After de-energization of the electromagnet, the precompressed spring biases the armature away from the driving hub disengaging the armature teeth from the teeth of the driving hub. The electromagnet is provided with a shaped coil and a conventional ball bearing rotatably supports the driving hub to form an economical compact clutch.

Abstract: A spring engaged and magnetically disengaged disc brake for engaging two opposing flat surfaces of a rotating disc such as to decelerate the rotating disc. The brake device includes a frame mounted in a fixed position relative to the rotating disc and a pair of identical brake subassemblies interposed portions of the frame and each of the opposing flat surfaces of the rotating disc. Each of the brake subassemblies includes an electromagnet fixedly interconnected with the frame, an armature interposed the electromagnet and one of the flat surfaces of the rotating disc, a spring interposed the frame and the armature to bias the armature towards the rotating disc when the electromagnet is de-energized, and a brake lining interposed the armature and the rotating disc. The frame may be formed of two magnet bodies fixedly interconnected with each other or of a single U-shaped stamping.

Abstract: A spring operated clutch having an input subassembly and an output subassembly. The input subassembly includes a sleeve member fixedly interconnected with an input drive shaft and provided with a double conical resilient frictional member on an outer cylindrical surface thereof. A first brake member is movably disposed within a bore of a second brake member, each of the brake members having frustoconical surfaces cooperating with one of two frustoconical surfaces of the frictional member. An adjusting member is movably interconnected with one of the brake members and a spring is interposed the adjusting member in the first brake member so as to bias the brake members into engagement with the friction member. The output subassembly includes an annular armature member having a first set of teeth extending therefrom and engageable with a second set of teeth which extend from the first brake member.

Abstract: An electromagnetic friction device for torque transmission, such device including an input member, and a mechanism for transmitting torque from the input member to an output member. The torque transmitting mechanism includes a friction ring member interposed the input member and the output member, a biasing member urging the friction ring into engagement with the input member, and a selectively operable biasing member, such as an electromagnetic device, for selectively biasing the friction ring member away from engagement with the input member. The torque transmitting mechanism further includes an overrunning adjustable abutment device interposed the friction ring and the input member to limit motion of the friction ring member towards the input member and thereby limit the torque frictionally absorbed therebetween.

Abstract: A clutch assembly for mounting to a rotatable element adjacent to a non-rotatable element. The clutch assembly has a first clutch member capable of being mounted to the rotatable element, a clutch body capable of being mounted to the rotatable element adjacent to the first clutch member, and a second clutch member axially movably interconnected with the clutch body. The first and second clutch members are normally biased into engagement. A brake is interposed the non-rotating element and the clutch body. The brake is automatically operable to inhibit rotation of the clutch body upon selective disengagement of the first and second clutch members.

Abstract: An electromagnetic clutch device for torque transmission from an input means to an output means which incorporates an air gap adjustment feature between the pole faces and the armature during assembly of the clutch. The air gap adjuster permits the armature to be responsive to magnetic flux formed by a predetermined electromagnetic coil voltage without having to tear down the assembly if the predetermined coil voltage is exceeded at initial try-out. Means are also incorporated to compensate for wear of the torque transmitting material.