A torque limiter device includes an input shaft having a first contact surface and an output shaft having a second contact surface. The input and output shafts are operable in an engaged position wherein the contact surfaces are brought into mechanical engagement, and a disengaged position wherein the contact surfaces are separated. A biasing mechanism provides a bias force that mechanically biases the input and output shafts in one of the positions and sets a threshold torque. An electromagnet is arranged to selectively provide an electromagnetic force that opposes the bias force when an activation current is supplied. A rotation sensor arrangement measures a respective rotation of the input shaft and of the output shaft. A controller determines a difference in rotations of the shafts and selectively supply the activation current to the electromagnet so as to disengage the input and output shafts when the rotation difference exceeds a threshold.

A clutch assembly includes a stationary journal bracket assembly having a base, a stub shaft that extends axially from the base, and a passage, a threaded bracket journal coupled to the stub shaft and accessible through the passage, pulley bearings supported on the threaded bracket journal, an integrated pulley/shaft including a pulley and a center shaft, and a clutch mechanism. The center shaft includes a cup-like hub and a distal portion that extends axially from the cup-like hub. The cup-like hub is supported on the pulley bearings, located at least partially within a blind hollow interior area of the cup-like hub. The threaded bracket journal is located at least partially within the hollow interior area of the cup-like hub.

A clutch assembly includes a stationary journal bracket assembly having a base, a stub shaft that extends axially from the base, and a passage, a threaded bracket journal coupled to the stub shaft and accessible through the passage, pulley bearings supported on the threaded bracket journal, an integrated pulley/shaft including a pulley and a center shaft, and a clutch mechanism. The center shaft includes a cup-like hub and a distal portion that extends axially from the cup-like hub. The cup-like hub is supported on the pulley bearings, located at least partially within a blind hollow interior area of the cup-like hub. The threaded bracket journal is located at least partially within the hollow interior area of the cup-like hub.

A sintered member having an annular shape, includes: a first face facing one side in an axial direction; a second face facing the other side in the axial direction; an inner peripheral face connected to an inner peripheral edge of the first face; and a plurality of tooth groups and a plurality of tooth-missing parts which are alternately disposed along a circumferential direction of the inner peripheral face. The second face includes a plurality of ball grooves arranged in parallel in the circumferential direction. Each tooth group includes a plurality of spline teeth that are continuous in the circumferential direction of the peripheral face. The number of plurality of tooth-missing parts is the same as the plurality of ball grooves. Positions in a radial direction in which the plurality of tooth-missing parts are formed are within ranges in the radial direction in which the ball grooves are formed.

A sintered member having an annular shape, includes: a first face facing one side in an axial direction; a second face facing the other side in the axial direction; an inner peripheral face connected to an inner peripheral edge of the first face; and a plurality of tooth groups and a plurality of tooth-missing parts which are alternately disposed along a circumferential direction of the inner peripheral face. The second face includes a plurality of ball grooves arranged in parallel in the circumferential direction. Each tooth group includes a plurality of spline teeth that are continuous in the circumferential direction of the peripheral face. The number of plurality of tooth-missing parts is the same as the plurality of ball grooves. Positions in a radial direction in which the plurality of tooth-missing parts are formed are within ranges in the radial direction in which the ball grooves are formed.

In some examples, an electromagnetic clutch assembly. The assembly includes a pair of clutch plates including a first clutch plate configured to rotate around a rotational axis; and a second clutch plate configured to rotate around the rotational axis. The assembly further includes an electromagnetic coil circumferentially surrounding the air gap, wherein the electromagnetic coil is configured to generate a magnetic flux passing through the first clutch plate and the second clutch plate, wherein the pair of clutch plates define an air gap between the first clutch plate and the second clutch plate in the absence of the magnetic flux, and wherein the magnetic flux is configured to cause at least one of the first clutch plate or the second clutch plate to move to close the air gap.

In some examples, an electromagnetic clutch assembly. The assembly includes a pair of clutch plates including a first clutch plate configured to rotate around a rotational axis; and a second clutch plate configured to rotate around the rotational axis. The assembly further includes an electromagnetic coil circumferentially surrounding the air gap, wherein the electromagnetic coil is configured to generate a magnetic flux passing through the first clutch plate and the second clutch plate, wherein the pair of clutch plates define an air gap between the first clutch plate and the second clutch plate in the absence of the magnetic flux, and wherein the magnetic flux is configured to cause at least one of the first clutch plate or the second clutch plate to move to close the air gap.

An electromagnetic coupling device includes an electromagnetic coil, a field core including a recessed portion containing the electromagnetic coil, and a terminal block inserted in a hole passing through the wall of the recessed portion. The terminal block includes a terminal portion projecting outside the field core, a pair of terminals provided at the terminal portion, and a pair of through holes passing through the terminal block via the pair of terminals. The winding start end and winding termination end of the electromagnetic coil pass through the pair of through holes, project from the pair of terminals, and are soldered to the pair of terminals together with a pair of external connection lead wires.

A bistable electromagnetic clutch is provided that includes a first part, a second part and an spring part. The first part includes a yoke with a plurality of iron cores, and an electromagnetic coil on each of the iron cores. The second part includes a moving carrier disc and a magnetic conductive disc that is fixed on a side of the moving carrier disc that is away from the yoke. Several magnets are fixed on the moving carrier disc, and the iron cores and the magnets are provided in a correspondence relation. The spring part is configured to keep the moving carrier disc and the yoke in normally separated positions. Two adjacent electromagnetic coils form a group, two electromagnetic coils in a same group are wound to form a group of windings with identical magnetic polarities, and corresponding two magnets form a group of magnetomotive forces with identical magnetic polarities.

A bistable electromagnetic clutch is provided that includes a first part, a second part and an spring part. The first part includes a yoke with a plurality of iron cores, and an electromagnetic coil on each of the iron cores. The second part includes a moving carrier disc and a magnetic conductive disc that is fixed on a side of the moving carrier disc that is away from the yoke. Several magnets are fixed on the moving carrier disc, and the iron cores and the magnets are provided in a correspondence relation. The spring part is configured to keep the moving carrier disc and the yoke in normally separated positions. Two adjacent electromagnetic coils form a group, two electromagnetic coils in a same group are wound to form a group of windings with identical magnetic polarities, and corresponding two magnets form a group of magnetomotive forces with identical magnetic polarities.