Methods and corresponding control devices for releasing an electric actuator in a reliable manner, such as an electric parking brake in particular, in a motor vehicle brake system. The aim of the invention is to provide an improved function and architecture which helps prevent the disadvantages of open-loop control systems when using a rationalized sensor system, thereby obviating closed-loop control systems. This is achieved by a release method and a corresponding electronic control unit which obtains an especially modulated change in the power requirement during the release process upon impacting the quasi-elastic release end stop of the electric actuating unit such that the change is fed back, the change being detected in order to be used as information for a power interruption or a termination of the power supply to the electric actuating unit.

The present invention relates drum brake system, comprising a back plate assembly and a brake drum (1) that is rotatable with respect to the back plate assembly, the back plate assembly comprising: a back plate (2); two brake shoes (3, 3′), the two brake shoes (3, 3′) being pivotably connected to the back plate (2), pivot axes (4, 4′) of the brake shoes (3, 3′) being disposed at or near first ends of the brake shoes (3, 3′); an actuator housing (5) with two pistons (6, 6′), the two pistons (6, 6′) being configured to move outwardly, to press each piston (6, 6′) against one of the brake shoes (3, 3′) to pivot the respective brake shoe (3, 3′) outwardly about its pivot axis (4, 4′), and to press the respective brake shoe (3, 3′) against the brake drum (1) for braking; a return spring (7) extending between the brake shoes (3, 3′) and being connected to both brake shoes (3, 3′), the return spring (7) being configured (7) to exert a retracting spring force that pulls both brake shoes (3, 3′) away from the brake drum; two tension springs (8, 8′) and a holder arrangement (9), inner ends of each of the two tension springs (8, 8′) being connected to the holder arrangement (9), an outer end of the first tension spring (8) of the two tension springs (8, 8′) being connected to a first brake shoe (3) of the two brake shoes (3, 3′) and an outer end of the second tension spring (8′) of the two tension springs (8, 8′) being connected to a second brake shoe (3′) of the two brake shoes (3, 3′).

The present invention relates drum brake system, comprising a back plate assembly and a brake drum (1) that is rotatable with respect to the back plate assembly, the back plate assembly comprising: a back plate (2); two brake shoes (3, 3′), the two brake shoes (3, 3′) being pivotably connected to the back plate (2), pivot axes (4, 4′) of the brake shoes (3, 3′) being disposed at or near first ends of the brake shoes (3, 3′); an actuator housing (5) with two pistons (6, 6′), the two pistons (6, 6′) being configured to move outwardly, to press each piston (6, 6′) against one of the brake shoes (3, 3′) to pivot the respective brake shoe (3, 3′) outwardly about its pivot axis (4, 4′), and to press the respective brake shoe (3, 3′) against the brake drum (1) for braking; a return spring (7) extending between the brake shoes (3, 3′) and being connected to both brake shoes (3, 3′), the return spring (7) being configured (7) to exert a retracting spring force that pulls both brake shoes (3, 3′) away from the brake drum; two tension springs (8, 8′) and a holder arrangement (9), inner ends of each of the two tension springs (8, 8′) being connected to the holder arrangement (9), an outer end of the first tension spring (8) of the two tension springs (8, 8′) being connected to a first brake shoe (3) of the two brake shoes (3, 3′) and an outer end of the second tension spring (8′) of the two tension springs (8, 8′) being connected to a second brake shoe (3′) of the two brake shoes (3, 3′).

A drum brake apparatus includes: a housing; a main braking unit disposed on a first portion of the housing, and the main braking unit configured to be, during main braking, driven by a hydraulic pressure and pressing a shoe; a parking braking unit disposed on a second portion of the housing, the parking braking unit configured to be, during parking braking, driven by an electromotive force of an actuator and pressing the shoe; a first locking member configured to couple the housing to one surface of a back plate; and a second locking member configured to couple the actuator to the housing on another surface side of the back plate.

A reduction motor for a parking brake mechanical actuator of a drum brake comprising an electric motor and a reduction gearbox, in which the electric motor comprises an output shaft extending along a first axis, the reduction gearbox comprises an output shaft extending along a second axis, and in which the reduction motor also comprises at least one angle gear between the electric motor and the reduction gearbox or at the output of the reduction gearbox, the angle gear comprising a crown gear-pair comprising a pinion and a crown gear, the pinion being engaged with the output shaft of the electric motor and meshing with the crown gear which is a part of the reduction gearbox.

An internal expanding shoe brake includes expansion pistons for forcing opposing brake shoes apart. In each expansion piston one adjusting pin is axially movably arranged and presses against a brake shoe web by means of a pressure piece. Said pressure piece is supported on the adjusting pin by means of a ball joint so as to pivot in any direction. In order to prevent the adjusting pin from being twisted inside the expansion piston, an anti-rotation element is provided and comprises a pressure piece projection which projects over the ball joint surface of the pressure piece, said projection interlockingly engaging in a receiving opening of the adjusting pin with lateral play and forming a rotational coupling connection.

An internal expanding shoe brake includes expansion pistons for forcing opposing brake shoes apart. In each expansion piston one adjusting pin is axially movably arranged and presses against a brake shoe web by means of a pressure piece. Said pressure piece is supported on the adjusting pin by means of a ball joint so as to pivot in any direction. In order to prevent the adjusting pin from being twisted inside the expansion piston, an anti-rotation element is provided and comprises a pressure piece projection which projects over the ball joint surface of the pressure piece, said projection interlockingly engaging in a receiving opening of the adjusting pin with lateral play and forming a rotational coupling connection.

The invention relates to an actuating device for an internal shoe brake, including an automatic adjusting device with an adjusting lever which includes a guide track in the form of a guiding slot with two opposing track surfaces which cooperate with opposing sides of a housing-fixed guide element in order to convert a displacement of the adjusting lever relative to the housing-fixed guide element into pivoting movements of the adjusting lever.

The invention relates to an actuating device for an internal shoe brake, including an automatic adjusting device with an adjusting lever which includes a guide track in the form of a guiding slot with two opposing track surfaces which cooperate with opposing sides of a housing-fixed guide element in order to convert a displacement of the adjusting lever relative to the housing-fixed guide element into pivoting movements of the adjusting lever.

A brake assembly having a brake spider that may receive an anchor pin or a sleeve that receives an anchor pin. Features such as splines may be provided with the anchor pin to help secure the anchor pin to the brake spider or the sleeve. Engagement features may be provided with the sleeve to help secure the sleeve to the brake spider.