Abstract: A lever device for a fuel injection valve includes a housing with a housing recess, at least one lever element arranged in the housing recess and having a coupling section coupled to a section of the housing, a drive element arranged in the housing recess and coupled to the at least one lever element to act upon the at least one lever element in the direction of a force-action axis, and an output element arranged in the housing recess and coupled to the at least one lever element such that the output element may be moved in the force-action axis direction by the at least one lever element. The coupling section of the lever element has at least one recess that defines at least two coupling section contact surfaces spaced apart from one another and resting against the housing section.

Abstract: A cylinder body 60 of a wheel cylinder assembly 6 for expanding a pair of brake shoes 3 and 4 by a pair of pistons 31 and 32 brought into contact with the respective brake shoes has a shape of a single straight pipe with both ends which are opened. The cylinder body 60 includes a first cylinder portion 35 for the one 32 of the pistons and a second cylinder portion 34 for the other 31 of the pistons. A valve seat 43 of a control valve 39 is arranged between the cylinder portions 34 and 35.

Abstract: Drum brake shoe, particularly for a motor vehicle, in which a brake cable (64) has an end terminal (66) for attachment to a lever (50) that acts on the shoe (4), this shoe comprising a rigid web one edge of which is formed with a cut-out (90) providing access to the cable (64) attachment end terminal (66) to make it easier to detach this cable.

Abstract: An adjustment arrangement for a non-servo drum brake having a hydraulic actuator that engages a first web of a first brake shoe and a second web of a second brake shoe. The hydraulic actuator on receiving a hydraulic input develops an actuation force for moving the first and second brake shoes from a rest position into engagement with a rotatable member to effect a brake application. An extendible member, that is connected to the first web and the second web, is extendable to define a running clearance in a rest position between the first and second brake shoes and the rotatable member. A lever arm, that is mounted on the first web, engages the extendable member. A resilient member extends between the lever to the second web to urge the first and second webs into engagement with the hydraulic actuator. The lever arm pivots on the first web as the first web moves through the running clearance during a brake application.

Abstract: An actuator for a drum brake comprises a housing (1), a screw mechanism having at least one screw (3, 6) and a nut (4, 7), which screw mechanism (2) is supported with respect to the housing (1), and drive means (3) which are drivingly connected to the screw mechanism for providing a linear movement of at least one of the screw and nut with respect to the housing upon driving the screw mechanism. The screw mechanism comprises two axially aligned screws which have opposite lead angles and two corresponding nuts, said screws each engaging a respective nut, the drive means being connected to both screws or to both nuts.

Abstract: This invention provides a duo-two leading type drum brake device which simplifies a drum brake structure as well as improves a transmission efficiency of a application force from a shoe actuator to brake shoes. A pivot lever 60 has an intermediate portion pivotally supported on the brake shoes 40. A shoe-actuator 20 is positioned adjacent to the first anchors 30, 30 and being disposed between the ends 60a, 50a of the pivot lever 60 and the other brake shoe 50. A strut 70 is positioned between and functionally engaged with the other ends 60b, 50b of the pivot lever 60 and the other brake shoe 50. An application force of the shoe actuator 20 is transmitted to the brake shoe 40 via a pivot section of the pivot lever 70 and transmitted to the other brake shoe 50 directly from the shoe-actuator 20 and indirectly via the strut 70.

Abstract: A parking brake mechanism in the duo-servo type drum brake includes a link type shoe drive mechanism for expanding a pair of brake shoes and an operating force generator for inputting a shoe operating force into an input lever of the shoe drive mechanism according to the brake operation. The parking brake mechanism also includes a parking brake lever pivotally supported by one brake shoe, wherein a shoe operating force is inputted into the input lever by swing of the parking brake lever, and the brake shoes are expanded via the shoe drive mechanism.

Abstract: Counter braking force acting on a secondary shoe is input to one end portion of a control lever supported with an anchor pin vertically provided on a backing plate in such a manner that the control lever is capable of swinging. An inner end portion in the radial direction of the control lever engages with a strut for pressing a primary shoe against a brake drum. Pressing force A with which the strut is pressing the primary shoe against the brake drum is drastically reduced when braking force, that is, the counter braking force increases and slightly reduced when the braking force, that is, the counter braking force decreases, whereby an increase or a decrease in the braking force is made automatically controllable.

Abstract: In order to indirectly open brake shoes (3, 4) through a link (19) pivoted on one of the brake shoes (3) at a location of a brake shoe holding mechanism (5), and to operate the brake shoes (3, 4) away from a shoe gap adjuster (11) while one of the brake shoes (3) is kept abutting against an anchor member (10), when rotating a lever (20) with a force (W) and operating a wheel cylinder (16) to operate brake shoes (3, 4), a moment of rotation caused by the return spring (13) is set to be larger than a moment of rotation caused by the return spring (15).

Abstract: A drum brake device is provided in which a single shoe extension device activated by the service brake can yield a braking force equivalent to that of a two leading (2L) type of drum brake device, and which facilitates the incorporation of a parking brake device and an automatic shoe clearance adjustment device. A link (10) is pivoted on an anchor pin (2), the central segment of the link (10) is engaged with the one brake shoe (4), a shoe clearance adjuster (14) is mounted between the link (10) and the other brake shoe (5) between the other pair of adjacent ends of the two brake shoes, wherein braking force can be mutually transferred between the two brake shoes (4, 5) by means of the link (10) and the shoe clearance adjuster (14).

Abstract: A parking brake assembly for connecting a cable to a lever. The lever has a generally flat base member pivotally mounted on the second brake shoe with a first end connected to the first brake shoe and a second end joined to a brake cable. The cable is located in a helical guide spring retained in a spring support which extends from the base member. A front face on the ramp is initially engaged by a tip of the cable while the slot forms a guide to allow an input force to move the tip over a lip on the end of the second tine. Once the tip has moved past the second tine, the cable tries to straighten out to eliminate any flexure induced by moving up the ramp by snapping into the slot and become aligned with the helical spring. A force applied to the cable which pulls the tip into engagement with a rear face on the ramp to complete the connection between the cable and lever. The projection assures that the cable remains located in the slot no matter how far the tip moves past the lip on the second tine.

Abstract: A brake assembly includes a guide spring for returning a parking brake actuator arm to a release position and which serves to guide an apply cable into engagement with the actuator arm during assembly. The guide spring is inhibited from deflecting during insertion of the cable by a retaining spring that spans across the opposing lower brake shoe ends at the adjuster link and which includes an extending tail positioned adjacent the guide spring.

Abstract: A duo-servo drum brake (10) includes an application adjuster mechanism (50). The application adjuster mechanism (50) comprises a threaded member (51) anchored to one brake shoe end (34), a socket member (61) anchored to the other brake shoe end (32), an opening (63) in the socket member (61) which freely receives a threaded shaft (53) of the threaded member (51), a starwheel (70) rotatedly mounted on the threaded member (51) and abutting an adjacent end (65) of the socket member (61), the socket member (61) having an axially extending button (64) and a torsion spring (90) disposed about its outer surface, the torsion spring having a hook end (95)engaging the button (64). A cable mechanism (60) has one end connected to the anchor pin (40) of the duo-servo drum brake (10) and the other end has a spring member (44) connected with a lever (80) of the adjuster mechanism (50).

Abstract: In a duo-servo drum brake comprising a mechanical expander adjacent a thrust bearing for supporting the brake shoes, with the expander including an operating lever to which is transmitted the operating force of an actuator substantially in a direction tangential to the edge of the brake drum. The brake shoe is movable through an expander in the direction of the operating force and connected to a thrust bearing through a prestressed spring. The spring force of the prestressed spring opposes the expanding force of the expander and exceeds the operating force required for placing the brake shoes in abutment with the brake drum on the operating lever.

Abstract: An automotive drum brake assembly includes first and second brake shoes mounted on a backing plate. A wheel cylinder for braking actuation is mounted between the brake shoes. An adjuster screw assembly is held between the brake shoes by an adjuster spring. The adjuster screw assembly includes a pivot nut threaded onto an adjuster screw. In one embodiment, a sleeve includes a first portion slidably mounted on the pivot nut, a second ramp portion covering the screw threads and a third portion opposite the pivot nut. The second portion, preferably formed as a frustoconical ramp, is slid by the adjuster spring to travel with the adjuster screw as it unthreads from the pivot nut, thereby shielding threads from corrosive elements.

Abstract: An improved operating mechanism for a drum brake assembly including a mounting flange for securing the brake assembly to a vehicle component, a hollow abutment block secured to the mounting flange, and a backing plate secured to the mounting flange. A pair of arcuate drum brake shoes are supported relative to the backing plate. The hollow abutment block located on the mounting flange between a pair of adjacent ends of the brake shoes. According to one feature of the present invention, the operating mechanism is at least partially disposed in the chamber for engaging and actuating the brake shoes, and is coupled to an actuation cable having an end portion supported in a generally perpendicular relationship relative to the backing plate.

Abstract: For a vehicle having a relatively large axle tube, a mechanically operated drum brake is provided having a hollow abutment post between adjacent ends of a pair of opposed arcuate brake shoes and having an improved actuating mechanism for the brake shoes mounted partially within the abutment post.

Abstract: The torsion/compression strut spring (60) is disposed about a forked end (54) of a parking brake strut (50) in a drum brake (10). The forked end (54) is received loosely about the web (12A) of an associated drum brake shoe (12) and a parking brake lever (40). The web includes a generally U-shaped recess portion (12B) which is sized to seat fixedly one oval-shaped end portion (64) of the spring. The spring (60) has oppositely disposed oval-shaped end portions (62, 64) which, in a disassembled and at-rest position, have longitudinal centerlines located 90.degree. apart relative to one another. When the spring (60) is assembled on the parking brake strut (50), the one end portion (64) seats fixedly within the recess portion (12B) and the other end (62) engages the strut (50) so that the spring (60) exerts a torsional force upon the strut (50) and causes legs (53, 56) of both forked ends (52, 54 ) of the strut (50) to engage respective sides of the parking brake lever (40) and drum brake shoe web (12A).

Abstract: A drum brake including a backing plate adapted to be mounted on a non-rotatable member of a vehicle, the backing plate having a shaft hole formed therethrough at the center thereof for accommodating a shaft of the vehicle, a drum adapted to be mounted on a rotatable member of the vehicle, a pair of brake shoes mounted on the backing plate and arranged to be expandable in the radial direction of the drum, a connector connecting respective ends of each of the brake shoes together, an anchor with which the other end of each of the brake shoes are engageable, and mounting bolts for mounting the backing plate on the non-rotatable member of the vehicle. The mounting bolts are located outwardly of the shaft hole and close to each other. The anchor is also fixed to the non-rotatable member of the vehicle by the mounting bolts.

Abstract: An adjusting device is disclosed for the brake shoes of inside shoe brakes. The adjusting device includes two levers which are articulated on a carrier at a lateral distance from one another. The levers each engage on one of two adjacent brake shoe ends and are jointly in engagement with a frustoconical endpiece of an actuating member guided rotatably on the carrier in a threaded bore provided between the levers and extending in parallel with a brake drum axis. During the rotation of the actuating member for the adjustment of the brake shoes, the two levers are pivoted in directions opposite to one another, being supported respectively on one of two mutually opposite edges of the brake-shoe webs so as to surround these. The adjusting device is merely attached by its levers on to the brake shoe webs so it can also execute self-reinforcing floating movements of the brake shoes in dual servo-brakes.

Abstract: A duo servo drum brake assembly having a parking brake actuating lever combined with an automatic brake adjuster strut, the combined lever and strut engaging adjacent ends of the brake shoes of the assembly for brake adjustment and parking brake actuation of the drum brake assembly. The parking brake actuating lever is pivotally and slidably mounted on the strut for planar pivotal and limited planar translational movements as the lever is subjected to parking brake apply and release forces. The lever has a cam end acting on the end of one brake shoe and on the strut to expand the combined lever and strut mechanism for parking brake actuation. The lever is shorter in overall length than the strut and is no longer than about 1/2 of the radius of the friction braking surface of the brake drum of the brake assembly, yet has effective force multiplication ratios for parking brake apply. The arrangement eliminates the spreader bar typically used in such priior art brake assemblies.

Abstract: An internal shoe brake, which is being used as a parking brake in a disc hub, is designed so that it can be preassembled in a ready-to-be-installed fashion. For that purpose, the anchor plate, serving as a cover plate, is mounted to a support by at least two fixing members. The fixing members are provided with heads which mesh free from play with bores provided in the axle support. Fixing of the support and the anchor plate to the axle support is effected through the intermediary of a screw. The screw and the fixing members jointly transmit the circumferential forces onto the axle support.

Abstract: A brake actuator has a body containing a pair of brake-applying members which may be actuated hydraulically to separate the friction elements of a brake into engagement with a rotatable braking surface. The members are interconnected by a mechanism in the form of a shaft of which respective end portions are provided with reversible threaded portions of opposite hand which engage corresponding threads within the members, the shaft being constrained against axial movement between bearings. Any excess movement of one of the members relative to the other is transmitted to that other member such as to cause an opposite and proportional force on the other member to substantially equalize the wear rates on the friction elements.

Abstract: The mechanically actuated brake (10) with automatic adjustment comprises an integral support plate (20) having first (22) and second (24) axially extending support bars which position associated pairs of brake shoe ends (13, 15, 17, 19). The brake shoe ends (13, 15, 17, 19) are biased together by respective spring mechanisms (16, 18), and the shoes (12, 14) are captured between the support bars (22, 24) and shoe web rests (21). A pawl (60) is attached to one (12) of the brake shoes (12, 14) and is biased by a resilient member (70). The pawl (60) includes a protrusion (66) which slidably engages an axially extending angled ramp surface (25) of the second support bar (24). An end (64) of the pawl (60) engages an adjuster mechanism (50) located between the second pair (17, 19) of brake shoe ends (13, 15, 17, 19).

Abstract: A drum brake assembly with the brake shoe lining friction surface subtending over a total effective friction surface arc length between the shoe heel and toe ends of about 49.degree. on the first or primary shoe, symmetrical about the shoe horizontal center line, and about 57.degree. on the second or secondary shoe, similarly symmetrical. The first or primary shoe may have about the same friction surface arc length as the second or secondary shoe in some instances, each then preferably being about 50% of the friction surface arc length of the prior art typical secondary shoe lining of about 117.degree.. Different methods of reducing the effective friction surface arc lengths are disclosed, as well as the effect on brake effectiveness variations the invention has on brake assemblies, both with the same lining material composition and different lining material compositions.

Abstract: A clamping bracket arrangement is provided which tightly grips the mounting boss of a wheel cylinder and the axle housing to which the brake assembly of which the wheel cylinder is a part is mounted, preventing movement of the wheel cylinder relative to the axle housing. The bracket arrangement may be quickly and easily installed in field service without the need for removing any parts of the brake assembly.

Abstract: The improved release mechanism comprises a load sensor (50, 51, 150, 250, 350, 450) connected with a wheel brake (10, 110) to sense a change in wheel braking torque and communicate responsively with a mechanical brake control device (200) or a braking assistance servo-motor system (310, 320; 410, 420) which releases the brakes when the vehicle commences acceleration along an incline.

Abstract: A drum brake assembly with a center guide backing plate, channeled web brake shoe assemblies slidably received on the center guide braking plate. A wheel cylinder assembly mounted in a notch on the center guide braking plate and engaged by a first set of adjacent brake shoe ends. A brake adjuster mounted between a second set of adjacent brake shoe ends, and retractor springs attached to the shoe assemblies and holding the shoe assemblies, wheel cylinder and brake adjuster in position on the center guide backing plate. The brake shoes are made of two identical shoe halves symmetrically formed about an axis so that the shoes also provide integral push rod-like which cylinder and adjuster engaging end.

Abstract: A self-centering brake assembly in which the leading shoe 12 and the trailing shoe 14 are connected in a duo servo braking mode. The connected ends of the shoes have an automatic adjuster comprising an adjuster lever return spring 70, an adjuster lever 74, a wire form link 76 and a pretension caged spring 78. The force of the adjuster lever return spring 70 and the placement of the wire form link 76 together with its pretension cage spring 78 develop a balanced force so that the moments about each anchored end of the shoe is substantially equal to 0. Shoes 12, 14 thus maintain concentricity of the brake shoe ring in relation to the brake drum 28.

Abstract: A continuous wireform is constructed as the cage (48) for a caged spring (50), these two components serving as the overtravel arrangement in an automatic brake adjuster. The wireform cage has a coil (70) formed at one end of the cage (48) and two limbs (72, 74) extend from the coil (70) and terminate in open ended complementary hook sections (86, 88) which are superimposed when the limbs (72, 74) are yieldably drawn together. A stretched coil spring (50) is then hooked to the integral coil (70) of the wireform and at the other end to the complementary hook sections (86, 88).

Abstract: A torque plate construction (50) comprises two stamped parts (58, 60) which are fastened together at central planar portions (62, 63) thereof and to a wheel axle housing (20) of a vehicle. Each torque plate part (58, 60) includes housing portions (77) spaced axially from the central planar portion (62, 63) of the respective plate part, the portions (77) providing a wheel cylinder housing (78). A piston cylinder (90) is disposed within the wheel cylinder housing (78), with a pair of bolts (100) and nuts (87) connecting together the portions (77) and securing the cylinder (90) within the housing (78). Each torque plate part (58, 60) has a pair of circumferentially spaced-apart notched portions (37) providing seats for a pin (40) extending from an associated brake shoe web (34), one web having an extension (39) extending between the torque plate parts to engage the piston (92).

Abstract: A drum brake assembly with a center guide backing plate, channeled web brake shoe assemblies slidably received on the center guide braking plate. A wheel cylinder assembly mounted in a notch on the center guide braking plate and engaged by a first set of adjacent brake shoe ends. A brake adjuster mounted between a second set of adjacent brake shoe ends, and retractor springs attached to the shoe assemblies and holding the shoe assemblies, wheel cylinder and brake adjuster in position on the center guide backing plate. The brake shoes are made of two identical shoe halves symmetrically formed about an axis so that the shoes also provide integral push rod-like which cylinder and adjuster engaging end.

Abstract: The brake comprises a torque control valve comprising a main piston which cooperates via a bearing piece with a shoe of which the bearing force is representative of the torque supplied by the brake during operation of the brake motor. The main piston controls the pressure admitted to the brake motor by a cut-off valve responsive to displacement of the main piston and by a variable volume decompression chamber of which a movable wall decompresses the fluid contained in the brake motor when the torque generated by the brake exceeds the limit of a predetermined torque-pressure law.

Abstract: An overrunning wheel brake has a brake drum, two brake shoes including a first brake shoe which, upon forward movement will be leading, and a second brake shoe, a bracket member provided with at least one guiding part arranged to support the first brake shoe, a tensioning member formed as an eccentric cam expanding the bracket in direction toward the drum and acting in running up direction of the first shoe, at least one incline provided on the first brake shoe in the region of its contact with the guiding part of the bracket member and forming relative to an outer curvature of the first brake shoe a wedge surface tapering in the running-up direction of the first brake shoe, an abutment member, and a displaceable pin arranged so that the brake shoes abut via the pin against one another and against the abutment member, and the tensioning member abutting with its free end against the second brake shoe via the pin.

Abstract: A drum brake assembly includes a pair of brake shoes (16, 18) which are movable by a hydraulic actuator (14) to a braking position. A parking brake lever assembly (24) is operable to also move the pair of brake shoes to the braking position. An anchor assembly (40) is attached to a backing plate (12) and is engageable with the pair of brake shoes to either absorb braking torque during a service brake application, or impart movement from one brake shoe to the other during a parking brake application. The anchor assembly includes a connecting member (44) engageable with the pair of brake shoes and rotatable in response to operation of the parking brake lever assembly to a released position on the anchor assembly (40).

Abstract: In a shoe and drum brake wherein the shoes can move circumferentially of the drum between first and second limit positions and are biased towards the first limit positions, there is provided for transmitting force from an actuator to the shoes a lever or hydraulic device capable of transmitting the force unequally to the shoes. The larger force urges the shoes towards their second limit positions while the smaller force urges the shoes towards their first limit positions. During forward rotation of the drum, the shoes remain in their first limit positions and can be applied radially to the drum by movement of the actuator. When the drum is rotating in the reverse direction, the larger force moves the shoes circumferentially of the drum so that the actuator fails to apply the shoes to the drum and establish a braking torque.

Abstract: A mechanical parking brake mechanism which comprises firstly a sector pulley pivoted on the backing plate of a brake drum to guide an intermediate portion of a parking brake wire and formed at its guide face with at least two radial recesses spaced from each other at a predetermined interval and secondly a parking brake wire integrally provided at its intermediate portion with at least two projections to be selectively engaged with the respective recesses of the sector pulley in accordance with the length of pulling stroke of the parking brake wire, thereby to avoid undesired excessive force acting on the parking brake wire and to enhance transfer efficiency in the input force applied to the parking lever of the mechanism.

Abstract: A wheel brake, particularly an overrunning wheel brake comprising a brake drum, first and second brake shoes movable in forward and rearward directions, amplifying formations arranged to cooperate with the first brake shoe and to amplify a force with which the first brake shoe is pressed against the brake drum, a displacing element for displacing the first brake shoe in the forward direction and thereby pressing the same against the brake drum with amplified pressure force, and an urging projection provided on the first brake shoe and arranged so that when the first brake shoe is displaced in the rearward direction, the projection displaces the second brake shoe which acts upon the amplifying formations and thereby the first brake shoe is again pressed against the brake drum with the amplified pressure force.

Abstract: In a drum brake assembly a pair of brake shoes (12, 14) are carried by a backing plate (10) and are engageable with the brake drum (18) to effect a service brake application. A parking lever (26) cooperates with the pair of brake shoes to engage the shoes with the brake drum and effect a parking brake application. A connector (34, 84, 94, 96) is slidably carried by the backing plate and pivotally anchors at least one of the brake shoes to the backing plate. The connector (34, 84) or another structure (128) transmits braking torque from one brake shoe to the other only during a parking brake application. The connector is releasably secured to the backing plate in a fixed position by a latch (36, 88, 114) which is connected to the parking lever. Movement of the parking lever to a position effecting a parking brake application causes the latch to release the connector for sliding movement relative to the backing plate.

Abstract: In a drum brake, a wheel cylinder is located between a pair of adjacent shoe ends for a pair of brake shoes and a piston inserted into the wheel cylinder is slidably engaged through an anchor provided on a backing plate and further the piston is provided with a flange on the side thereof pressing a brake shoe so that the anchor is interposed between the flange of the piston and the wheel cylinder, and, furthermore, a strut is located between the other pair of adjacent shoe ends for the pair of the brake shoes in order to lighten a weight of the brake and facilitate a disassembly and assembly of the brake.

Abstract: In a drum brake assembly a hydraulic actuator is engageable with a pair of brake shoes to move the same into engagement with a rotatable member. A parking lever also cooperates with the pair of brake shoes to move the same into engagement with the rotatable member and an anchor plate forms a connecting member between the pair of brake shoes. A backing plate supports the pair of brake shoes and the anchor plate. The anchor plate is movably supported by the backing plate and a latch cooperates with the anchor plate in a first position to fix the anchor plate to the backing plate. The latch is movable to a second position spaced from the anchor plate to permit the latter to move relative to the backing plate. In order to control the position setting of the latch, the latch is coupled to the parking lever so that the latch remains in the first position until the parking lever is moved whereupon the latch is also moved to the second position.

Abstract: A drum brake of the type comprising two brake shoes adapted to be spaced apart by a wheel cylinder. The distance between the ends of the shoes which cooperate with the wheel cylinder is automatically increased to compensate for the wear of the brake linings by an adjusting device which defines the rest position of the ends. The device comprises an extensible member of the screw and nut type, two annular resilient members which grippingly engage corresponding cylindrical portions of the extensible member, and a cam which rotates the resilient members one relative to the other in a first direction upon a brake application and in the opposite direction upon brake release to limit extension of the extensible member to a predetermined value.

Abstract: The brake shoe webs of a drum brake have apertures provided adjacent the shoe ends which engage the adjusting screw. The ends of the adjusting screw spring are so shaped that they can extend through the apertures with a reverse bend of generally V configuration, causing the terminal ends of the spring to move outwardly to hook on the opposite side of each shoe web from the main spring body. A pair of spaced, axially parallel notched shafts are provided as parts of a tool for installation. The shafts receive the spring hooked ends in the notches, move apart along the axis of the spring coiled body section to tension the spring and to align the spring hooked ends with the shoe web apertures. The shafts are then moved axially to push each spring end through its aperture. The shafts are then retracted, leaving the spring hooked ends attached to the shoes.

Abstract: In an internal shoe-drum brake of the duo-servo type a strut assembly with which non-actuated shoe ends engage is slidably guided in an open-ended through bore in a fixed housing and the length of the strut assembly is substantially greater than the maximum transverse dimension thereof.

Abstract: A vehicle brake having a pair of brake shoes moveably mounted and arranged in end-to-end relationship on a fixed backing plate. A pair of levers is pivotally mounted on the backing plate. The levers have thrust transmitting portions which are interposed between a pair of opposed brake shoe ends and a hydraulic service brake actuator for moving the brake shoes into engagement with the brake drum. The levers also have swinging end portions which pivot inwardly in opposite directions upon outward movement of the thrust transmitting portions. The lever thrust portions have concavely curved camming surfaces which slidably engage complementary convexly curved brake shoe end surface for transmitting the hydraulic actuator force to the brake shoes. A mechanically actuated parking brake mechanism is mounted on the backing plate and is operatively connected to the lever swing end portions by a pair of links.

Abstract: A mechanically actuated parking brake having a pair of brake shoes movably mounted and arranged in end-to-end relationship on a fixed backing plate. A pair of levers is pivotally mounted on the backing plate. The levers are interposed between a pair of opposed brake shoe ends and a hydraulic actuator for moving the brake shoe into engagement with the brake drum upon actuation of the vehicle service brake. The branch legs of a Y-shaped cable extend between the swinging ends of the levers with the main cable leg extending about a pulley and connected to a windup reel. The windup reel is rotatably mounted on one end of a brake actuating handle, with the other end of the handle being connected to a parking brake actuating pedal or lever. Application of the vehicle parking brake rotates the windup reel upon rotation of the handle which tensions the cable and draws the lever ends inwardly and expands the brake shoes outwardly into engagement with the brake drum.

Abstract: A drum brake, primarily for a trailer, which gives normal braking torque in forward direction and low torque in reverse. This is achieved by having a pivoted lever acting between the one ends of two shoes remote from the ends between which the brake actuator is located. The shoes act on the lever at different effective radii and the forces applied by the shoes to the lever hold it in a first position during forward rotation, thus allowing normal braking torque, and a second position during reverse rotation which allows the ends of the shoes acted on by the actuator to move apart thus allowing a limitation of the reverse braking torque by limiting the stroke of the actuator.

Abstract: A thrust transmitting assembly, particularly useful as a shoe tip abutment for an internal shoe drum brake, has a cylindrical output member and a slidable input member in the form of a piston, the members being transmissively coupled by a fluent material, such as an elastomeric material, which transmits input thrust in one direction to the output member in the same direction but at a higher velocity.

Abstract: An abutment assembly for an internal shoe drum brake, particularly a vehicle wheel brake, comprising a pair of opposed abutment members for engagement with respective ends of the brake shoes and an arrangement for transmitting only part of the input force applied to one abutment member, to the other abutment member. The arrangement comprises a plurality of individual force-transmitting members each pivotally supported between and engaging the said one abutment member and an output member coupled to the other abutment member.

Abstract: A drum brake, primarily for a trailer, which gives normal braking torque in forward direction and low torque in reverse. This is achieved by having a pivoted lever acting between the one ends of two shoes remote from the ends between which the brake actuator is located. The shoes act on the lever at different effective radii and the forces applied by the shoes to the lever hold it in a first position during forward rotation, thus allowing normal braking torque, and a second position during reverse rotation which allows the ends of the shoes acted on by the actuator to move apart thus allowing a limitation of the reverse braking torque by limiting the stroke of the actuator.