Abstract: The present disclosure relates to vehicle drum brakes. In one aspect, there is provided a brake shoe comprising a guide at or near its free end, which prevents brake shoe misalignment. According to a further aspect, there is provided a guide for attachment to a brake shoe at or near its free end, which prevents brake shoe misalignment. According to a further aspect, there is provided a drum brake assembly comprising a brake shoe comprising the guide.

Abstract: An S-cam brake includes an S-cam unit for braking a drum, where the S-cam unit includes an S-cam of an “S” shape having an involute tooth profile at left and right sides thereof, and horizontal tangential members forming contacting surfaces engaged with the involute tooth profile symmetrically around a center point of a circle at the left and right sides of the S-cam, and being spread at the left and right sides with normal lines of the contacting surfaces as a horizontal direction when the S-cam rotates.

Abstract: An apparatus for operating a parking brake that can reduce an operation stroke. A connecting member has shoe insert grooves with brake shoes inserted into both sides thereof. A first operation lever has one end rotatably combined with one side face of the connecting member and contacts with one of the brake shoes. A second operation lever has one end combined with the other end of the first operation lever and the other end rotatably combined with the other side face of the connecting member and contacts with the other one of the brake shoes.

Abstract: A cam mechanism 7 provided as a shoe drive mechanism includes a cam supporting plate 21 being loosely and rotatably fitted on an anchor pin 10 for receiving a shoe operating force, a first cam plate 23 rotatably connected to the cam supporting plate 21 at an outer cam supporting position which is a position shifted away from the anchor pin 10 radially outwardly of the drum, a second cam plate 25 rotatably connected to the cam supporting plate 21 at an inner cam supporting position which is away from the anchor pin 10 toward the operating force generating means 6, so that a pair of brake shoes 3, 4 are opened outwardly by the separate cam plates 23, 25, respectively.

Abstract: The invention relates to a vehicle drum brake including a wheel cylinder including two pistons and lever device installed at the wheel cylinder to be rotated by a parking cable to linearly move the two pistons of the wheel cylinder apart. The present invention compacts the parts of the drum brake relevant to the mechanism for braking a running or parking vehicle and prevents noise generated between the separately constructed manipulating lever and brake shoes, when they are in contact.

Abstract: A bushing boot for a cam braking system is disclosed that snaps in place over a bushing assembly. The bushing assembly supports a camshaft in the cam braking system. The bushing boot is preferably generally cylindrical having a first end, a second end and an internal bore extending along a longitudinal axis. In a preferred embodiment, the boot also has an internal circumferential groove within the bore at its first end and an external circumferential groove at its second end. The bushing assembly includes a washer at an end adjacent the boot. The internal groove of the boot snaps in place over the outside diameter of the bushing assembly washer, thereby providing an axial locating feature. The internal bore of the boot receives the camshaft. Further, the external groove on the boot receives a tie strap to connect the boot to the camshaft. In the preferred embodiment, the boot rotates with the camshaft. In an alternative embodiment, the boot does not have an external circumferential groove.

Abstract: A drum brake comprising a support plate with first and second shoes mounted thereon. Each shoe includes a web and a rim with a friction material being secured to the rim. A hydraulic actuation device acts on a first end of each web of the first and second shoes to move the friction material on the rims into engagement with a drum to effect a brake application. A spacer located in the vicinity of the hydraulic actuation device acts on the web of each shoe to establish the distance between the first and second shoes. Each web has a second end which engages a bearing component secured to the support plate. A mechanical actuation device has a first link connected to the web of the first shoe and a second link connected to a force transmission device.

Abstract: A brake actuator assembly is disclosed for expanding internal shoe brakes in which a pair of brake shoes (17) are disposed within a brake drum (11). A pair of cam members (33,35) are fixed to a pair of cam shafts (41,43) and are operable to engage the brake shoes by use of cam followers (37,39), in response to a brake input (56,55). The cam shafts (41,43) are timed relative to each other by a pair of gears (73,75). The disclosed actuator assembly ensures that the cam members rotate through the same angular magnitude, but the amount of torque transmitted to each cam is determined by the braking force required for the respective brake shoe. The disclosed actuator assembly provides for substantially greater lift, for longer shoe wear life, without taking up as much space in the radial direction as would an equivalent S-cam arrangement.

Abstract: A normally engaged (dead man's) brake for a manually operable pallet truck. A spring-biased, levered cam is housed within a wheel subassembly frame. Two wheels that are axle-mounted to the frame contain integral brake drums and are mounted so as to circumferentially superimpose the drums over brake shoes which are pivotally mounted to the frame. Under normal, non-operational conditions, the levered cam forces the brake shoes into registry and contact with the drums, thereby conditioning a brake-engaged mode. A manual control lever is cable-connected to the frame in a fashion to enable overcoming the spring biasing of the levered cams, thereby releasing the brake. The moment manual force is released, the levered cams return to the normal, brake-engaged mode, thus effecting the invention's purpose.

Abstract: A replaceable roller insert is provided for supporting a cam roller follower within roller supports acting against a cam element moving at least one brake shoe inward and outward relative to a brake drum where the roller insert is easily replaced by removing a worn roller insert and mounting a replacement roller insert to the brake shoe web.

Abstract: A roller follower (12) and bracket (20) combination for use in a rotary cam type brake shoe assembly (100) is provided in which bracket (20) is supported on a web (2) of a brake shoe in such a manner that, when a free-end (27) of bracket (20) is inserted into an opening (26) in a trunnion (24) of a pin (11) that supports roller follower (12) for rotation, bracket (20) is operative to prevent roller follower support pin (11) from being rotated by the cam to lessen noise heretofor created by the rotation of trunnion (24) against web (2).

Abstract: A roller retainer for a cam actuated vehicle brake assembly comprising a member preferably formed from spring wire to provide two substantially parallel legs with a tang at the end of each leg and a manual grip intermediate the legs. The tangs are seated in apertures provided to a dual web brake shoe and a portion of the member intermediate the manual grip and the tanged ends extends only partially around the roller so the manual grip and the tanged ends are disposed on the same side of a reference plane parallel to the legs and passing through the axis of the roller. This enalbes the retainer to be rotated about the apertures thereby allowing the roller to be safely removed from the brake shoe while the shoe remains in the assembly without the use of any tools.

Abstract: A roller retainer for retaining a cam following roller in a pair of laterally aligned open-ended recesses provided at adjacent ends of a pair of axially spaced brake shoe webs comprising a length of spring wire formed to provide a pair of spaced substantially parallel legs, a bridge portion joining the legs and a U-shaped ear at the junction of each leg and the bridge. Each of the legs has an end formed to encircle at least 180.degree. of a trunnion surface of the roller and the bridge portion is of a length greater than the space between the legs and is formed to permit resilient deformation of the bridge while moving the ears toward one another whereby the retainer may be readily deformed to engage or disengage the ears with laterally aligned apertures provided to the spaced brake shoe webs.

Abstract: A drum brake assembly includes a pair of brake shoes which are carried by a backing plate and engageable with a hydraulic actuator. The hydraulic actuator is operable to move the pair of brake shoes from a rest position to a braking position. A strut extending between the pair of brake shoes cooperates with a parking arm to move the pair of brake shoes to the braking position during a parking brake application. A support assembly on the backing plate is disposed opposite the hydraulic actuator for the purpose of absorbing braking torque developed by the pair of brake shoes. The support assembly comprises a pair of slots and a lever. The lever is movable in response to movement of the parking arm to adjust the position of the pair of blocks relative to each other. In a first position the blocks are in abutment with the backing plate while in a second position the blocks are free to move a limited amount relative to the backing plate.

Abstract: A drum brake assembly includes a pair of brake shoes which are movable to a braking position by a hydraulic actuator. In order to maintain the pair of brake shoes adjacent the drum an adjuster is disposed between the pair of brake shoes opposite the hydraulic actuator. The adjuster carries a parking mechanism to manually move the pair of brake shoes to the braking position independently of the hydraulic actuator. The parking mechanism comprises a pair of levers which are pivotally connected to projections on the adjuster and the levers oppose one of the pair of brake shoes such that pivoting of the pair of levers moves the adjuster and the other brake shoe away from the one brake shoe. A spacer and a washer are disposed between the one brake shoe and abutment surfaces on each pair of levers and the adjuster movably supports the spacer and the washer.

Abstract: A wheel brake assembly in which the webs of brake shoes are held in a planar alignment between and supported by a pair of parallel-spaced interconnected supporting plates, in turn supported by an axle or spindle. A pair of brake contracting springs interconnect the brake shoes, and these springs are positioned with one spring being against the outer surface of each plate. An inner edge of each of the plates is circular and independently adapted to attach to an axle housing, whereby the brake assembly may be readily welded to an axle housing.

Abstract: In an internal shoe-drum brake of the duo-servo type for vehicles adjacent shoe ends are separated by an angularly movable cam. The cam is moved angularly by a separate cam lever to which it is coupled, and the cam is permitted a circumferential movement both with the shoe ends and relative to the lever in the application of the brake.

Abstract: An electrically controlled brake assembly for a vehicle wheel of the type in which an operating arm is mounted between its ends to turn about a pivot on a backing plate and carries at least one electromagnet on one of its ends. Two downwardly projecting tongues are formed on the lower end of the pivoted operating arm of the brake assembly and ride in a channel defined by a guide which is attached to the backing plate of the assembly, the tongues and the guide coacting to prevent the operating arm from cocking on its pivot during braking.