A brake assembly having a non-braking configuration and a braking configuration includes a brake shoe having a brake lining coupled thereto. An actuator is coupled to the brake shoe, the actuator movable along an actuation path between a neutral actuator position and a braking actuator position. An actuator distance between the neutral actuator position and the braking actuator position increases over time in response to a reduction in thickness of a brake lining installed on the brake shoe. Moving the actuator from the neutral actuator position to the braking actuator position past a predetermined actuation distance causes a ratchet mechanism to advance to a next sequential ratchet position, which in turn moves the neutral actuator position of the actuator a predetermined distance away from the minimum actuator position. A sensor is coupled to the ratchet mechanism for detecting the sequential ratchet position of the ratchet mechanism.

The rotation-actuated drum brake uses both inner and outer sets of brake shoes, which are actuated in a radial manner, to contact the inner and outer surfaces of a cylindrical brake drum. The inner and outer sets of brake shoes are disposed within an annular brake housing and are constrained to move radially. An actuator selectively drives rotation of a rotating disc having a plurality of arcuate slots defined therein. This drives roller guides of the inner and outer sets of brake shoes to roll within respective ones of the arcuate slots. The driven rolling of the roller guides drives the radial motion of the inner and outer sets of brake shoes to simultaneously frictionally engage the inner and outer surfaces of the cylindrical brake drum.

The rotation-actuated drum brake uses both inner and outer sets of brake shoes, which are actuated in a radial manner, to contact the inner and outer surfaces of a cylindrical brake drum. The inner and outer sets of brake shoes are disposed within an annular brake housing and are constrained to move radially. An actuator selectively drives rotation of a rotating disc having a plurality of arcuate slots defined therein. This drives roller guides of the inner and outer sets of brake shoes to roll within respective ones of the arcuate slots. The driven rolling of the roller guides drives the radial motion of the inner and outer sets of brake shoes to simultaneously frictionally engage the inner and outer surfaces of the cylindrical brake drum.

An illustrative example drum brake device includes a drum having an inner, braking surface. At least one brake shoe includes a friction lining and a support structure for the friction lining. The support structure includes a window having a first portion that is wider than a second portion. A shoe mount is configured to be received through the first portion of the window and engage the support structure adjacent the second portion of the window in a manner that resists movement of the brake shoe in two dimensions and allows selective movement of the brake shoe in a third dimension for allowing the friction lining to selectively engage the braking surface.

An illustrative example drum brake device includes a drum having an inner, braking surface. At least one brake shoe includes a friction lining and a support structure for the friction lining. The support structure includes a window having a first portion that is wider than a second portion. A shoe mount is configured to be received through the first portion of the window and engage the support structure adjacent the second portion of the window in a manner that resists movement of the brake shoe in two dimensions and allows selective movement of the brake shoe in a third dimension for allowing the friction lining to selectively engage the braking surface.

A drum brake device for a vehicle includes a first brake shoe and a second brake shoe movably coupled to a back plate, and spaced apart from each other; a wheel cylinder positioned between one end of the first brake shoe and one end of the second brake shoe, and configured to expand the distance between the one end of the first brake shoe and the one end of the second brake shoe; and an actuator positioned between another end of the first brake shoe and another end of the second brake shoe, and configured to provide a driving force to expand the distance between the one end of the first brake shoe and the one end of the second brake shoes and to expand the distance between the another end of the first brake shoe and the another end of the second brake shoe.

A drum brake device for a vehicle includes a first brake shoe and a second brake shoe movably coupled to a back plate, and spaced apart from each other; a wheel cylinder positioned between one end of the first brake shoe and one end of the second brake shoe, and configured to expand the distance between the one end of the first brake shoe and the one end of the second brake shoe; and an actuator positioned between another end of the first brake shoe and another end of the second brake shoe, and configured to provide a driving force to expand the distance between the one end of the first brake shoe and the one end of the second brake shoes and to expand the distance between the another end of the first brake shoe and the another end of the second brake shoe.

A radial wedge clutch, including: an axis of rotation; a shaft; an outer ring located radially outward of the shaft; a cage radially disposed between the shaft and the outer ring; a plurality of circumferentially aligned wedge plate segments radially disposed between the shaft and the outer ring; at least one resilient element urging the plurality of circumferentially aligned wedge plate segments radially outwardly; and an actuation plate axially displaceable in a first axial direction to engage the cage and rotate the cage and the plurality of circumferentially aligned wedge plate segments.

A brake assembly having a non-braking configuration and a braking configuration includes a brake shoe having a brake lining coupled thereto. An actuator is coupled to the brake shoe, the actuator movable along an actuation path between a neutral actuator position and a braking actuator position. An actuator distance between the neutral actuator position and the braking actuator position increases over time in response to a reduction in thickness of a brake lining installed on the brake shoe. Moving the actuator from the neutral actuator position to the braking actuator position past a predetermined actuation distance causes a ratchet mechanism to advance to a next sequential ratchet position, which in turn moves the neutral actuator position of the actuator a predetermined distance away from the minimum actuator position. A sensor is coupled to the ratchet mechanism for detecting the sequential ratchet position of the ratchet mechanism.

In a predetermined first state, a distance (D.sub.1) in a second direction between a contact portion (P.sub.in) between a input-side engaging part (9) and an input-side engaging part (17) and a rotation center (O) is larger than a distance (D.sub.2) in the second direction between a contact portion (P.sub.out) between an output-side engaging part (12) and an output-side engaged part (14) and the rotation center (O). In a locked state or a semi-locked state, a contact portion (C.sub.1) between the output-side engaging part (12) and the output-side engaged part (14) is located closer to the rotation center (O) of the output member (4) in a first direction than an imaginary straight line (L) connecting a contact portion (C.sub.2) between one pressing surface (13) of the pair of pressing surfaces (13) and a pressed surface (6) to the rotation center (O) of the output member (4).