摘要:
A brake device for a vehicle may include: a driving unit positioned in a drum and supplying rotation power; a nut screw positioned between first and second brake shoes; a first push rod having both sides connected to the first brake shoe and the nut screw, and pressurizing the first brake shoe through the rotation of the nut screw; a fixing protrusion fixed to a case surrounding the nut screw; a rotation connection part coupled to the fixing protrusion to restrict rotation of the rotation connection part; a rotation control part inserted into the rotation connection part so as to be screwed to the rotation connection part; and a second push rod having both sides connected to the second brake shoe and the rotation control part, and moved together with the rotation control part in a longitudinal direction so as to pressurize the second brake shoe.
摘要:
To reduce the number of components of the automatic shoe clearance adjustment apparatus and to improve the ease of assembly of the same, the proximal portion of the driving member is fixed on the strut. The operating portion and the arm of the driving member are integrally formed therewith is placed between the brake shoe and the strut. The operating portion together with the arm of the driving member are moved (rotated) so as to follow the movement of the brake shoe by utilizing the resilient force of the driving member, and the pawl at the end of the arm drives the adjustment teeth of the strut to extend the entire length of the strut.
摘要:
This dual mode drum brake provides less stroke loss during the brake operation; a stable parking brake effectiveness; and a comfortable feeling for the operator during the brake operation. A wheel cylinder actuator (15) is positioned between ends (11d) and (12d) of first and second brake shoes (11), (12); an anchor block (16) is positioned between the other ends (11e) and (12e); a shoe clearance adjustment device (18) is extended adjacent to the wheel cylinder actuator (15); a parking brake actuator (23) is extended adjacent to the anchor block (16); a bent portion (22c), formed on one side (22b) of a pivot lever (22) pivotally supported on the first brake shoe (11), is inserted between the first brake shoe (11) and the shoe clearance adjustment device (18) while the other side (22d) of the pivot lever (22) functionally engages with the parking brake actuator (23).
摘要:
A parking brake assembly for an automotive drum brake is provided. The parking brake assembly replaces a conventional mechanical strut with an electronic strut actuator subassembly that provides for parking brake engagement and disengagement, sensing of brake lining wear and adjustment of brake shoe-to-drum clearance.
摘要:
A small diameter duo two leading type drum brake that can mount a built-in parking brake mechanism. The brake has a link mechanism that includes a pivot lever that is rotatably and pivotally supported at a central region of a first brake shoe. A first strut is provided between a first end of a pivot lever and a second brake shoe. A second strut is substantially parallel to the first strut and is provided between the second end of the pivot lever and the second brake shoe. A parking brake actuator is provided to activate the link mechanism to open the pair of first and second brake shoes. A service brake actuator has an automatic shoe clearance adjustment device and one of the first and second struts has an automatic parking stroke adjustment device.
摘要:
A brake adjuster comprises a variable length strut (16) having two end portions (30, 31) and an intermediate portion (32) therebetween which is in screw threaded engagement with one of the end portions (31). A pawl (39) is attached to the other end portion (30) and engages an array of ratchet teeth (38) the intermediate portion (32). As the end portions of the strut (30, 31) move apart during a brake application the pawl (39) rides up a flank of a ratchet tooth (38a) and if the movement apart exceeds a predetermined amount engages behind the tooth (38a). When the end portions (30, 31) move towards each other in the next brake disengagement, the intermediate portion (32) is rotated relative to said one of the end portions (31) to increase the effective length of the strut (16). The pawl (39) may be bi-metallic and arranged to disengage the ratchet teeth (38) if the temperature of the adjuster rises above a predetermined level.
摘要:
A single shoe drum brake device which provides stable braking effect by tending to equalize the braking effect when the vehicle is moving forward and backward without losing self-servo property during moving either forward or backward. Additionally, the device avoids damage to the brake pipe due to objects such as flying gravel, debris, and the like by locating the wheel cylinder in upper portion of the brake device. Further, the structure enables the run of the parking brake cable to be directed entirely toward the front of the vehicle. One of two anchors (10, 14) is positioned so that the distance from a horizontal straight line through the brake center (0) and across the brake shoe (3) to that anchor is shorter than the distance from the line to the other anchor. This one anchor is a pivot shoe anchor and the other anchor is a floating shoe anchor.
摘要:
A drum brake device having a single brake shoe mounted to be movable on top of the back plate. One end of the brake shoe abuts against an anchor (10) and the other end interlocks with a shoe clearance adjustment device (14). A link (11) is supported so as to pivot in the central region of the brake shoe (3). One end of the link (11) is interlocked so as to be activated by a service brake actuator (12) itself activated when the service brake is applied, while the other end of the link (11) abuts against the anchor (10). When the brake drum is rotating in one direction, the other end of the brake shoe (3) is supported by the anchor (10), and when the brake drum is rotating in the reverse direction, the one end of the brake shoe (3) is supported by the shoe clearance adjustment device (14).
摘要:
A dual mode drum brake assembly includes a backing plate, a brake drum, and first and second brake shoes supported on the backing plate and movable into frictional engagement with the brake drum. The drum brake assembly further includes a service brake mechanism for selectively moving the brake shoes into frictional engagement with the brake drum, and a rotation preventing abutment secured relative to the backing plate and disposed between and engageable with the brake shoes. A pivot lever is pivotally supported relative to the first brake shoe and is operatively coupled to exert an outward force on the first brake shoe when the parking and emergency brake is actuated. A first strut is disposed adjacent the hydraulic actuator and includes one end coupled to the second brake shoe and opposite end coupled to one end of the pivot lever. A second strut is disposed adjacent the rotation preventing abutment and includes one end coupled to the second brake shoe and an opposite end coupled to an opposite end of the pivot lever. The drum brake assembly further includes an actuation cable having an end portion supported in a generally perpendicular relationship relative to the backing plate, and a parking and emergency brake actuating means carried by the brake assembly and coupled to the actuation cable for mechanically actuating the pivot lever to urge the first brake shoe outwardly into engagement with the brake drum and thereby initiate duo-servo actuation of the parking and emergency brake through one of the first and second struts.
摘要:
An actuating lever for a parking and emergency brake mechanism for use in a vehicle drum brake assembly includes a backing plate mounted on the vehicle for supporting a pair of brake shoes. A service brake mechanism is provided for selectively moving the brake shoes apart from one another into frictional engagement with an inner friction surface of a brake drum mounted on a wheel of the vehicle. The brake shoes include respective web portions which are generally flat and crescent-shaped. Arcuate table portions are secured to the opposed outer curved surfaces of the web portions, such as by welding, and friction pads are secured to the outer arcuate surfaces of the table portions of the brake pads. An aperture is formed through the upper end of the web portion of one of the brake shoes. The actuating lever for the parking and emergency brake mechanism is pivotally supported on the one brake shoe. The actuating lever includes a generally flat and arcuate body portion having a stiffening rib formed along a portion thereof. A hollow cylindrical boss is formed integrally with the upper end of the body portion, extending upwardly from one side thereof. The upstanding integral boss of the actuating lever extends through the aperture formed through the upper web portion of the brake shoe. As a result, the actuating lever is retained on the brake shoe for pivoting movement relative thereto about the boss without any undesirable looseness or play therebetween, and without the use of additional parts or significant installation time.