Abstract: A structural unit for a drum brake comprises at least one brake shoe (12) and an adjusting device (32) which comprises an adjusting strut (34), a ratchet-detent wheel mechanism and an adjusting lever (40) which comprises the ratchet (52). The brake shoe (12) has a web (22) against which the adjusting strut (34) rests and on which the adjusting lever (40) is pivotably mounted by means of a bearing pin (56). In order to enable the structural unit with the adjusting device (32) to be easily retrofitted also in the case of older drum brakes the bearing pin (56) is attached to a separate carrier member (66) which can be slid onto the web (22) of the brake shoe (12) in a clamping manner and which comprises at least one first offset (84) which positively engages a recess (86) provided in the web (22). In this manner, the bearing pin (56) is reliably and true-to-position secured at the brake shoe web (22).

Abstract: A dual-mode drum brake assembly including a stationary backing plate opposed to a brake drum, a wheel cylinder disposed on the backing plate and having a pair of outwardly extendible pistons, an anchor fixed to the backing plate and opposite to said wheel cylinder diametrically of the backing plate, two brake shoes movably supported by the backing plate and having a first pair of adjacent ends opposite to the wheel cylinder and a second pair of adjacent ends opposite to the anchor, a parking lever disposed substantially along one of the two brake shoes and having a pivot axis perpendicular to the backing plate, at a portion thereof closer to the wheel cylinder, and a cable fixing portion closer to the anchor, and a link mechanism disposed between the parking lever and the brake shoes, and operating to move the adjacent ends of the second pair of the brake shoes away from each other, with a pivotal movement of the parking lever about the pivot axis when a torque acts on the brake drum.

Abstract: A parking brake assembly includes a lever that translates pivoting rotation to sliding movement of a tappet in contact with a braking shoe to effect expansion of the brake shoe against the inside diameter of a rotating element. The rotating element is, in more specificity, a rotor carried by a spindle that is rotatably supported by bearings. The bearings are carried by the actuator housing which additionally carries the lever and tappet of the parking brake assembly.

Abstract: The invention is drum brake assembly having a dual brake actuator. A piston-cylinder assembly forms the primary brake actuator, and a lever member, together with the piston-cylinder assembly, forms a composite structure which acts as a secondary brake actuator. The lever member pivots about an axis substantially parallel to the axis of rotation of the drum, and the lever member is contained within the drum brake assembly. The piston-cylinder assembly is operable independent of the composite structure to actuate the brake.

Abstract: A method of installing a vehicle spindle and brake assembly on a vehicle component. First, the spindle and brake assembly are "preassembled" into a complete brake unit. The preassembled spindle and brake assembly includes a spindle, a rotatable component, a bearing member for supporting the rotatable component relative to the spindle, and a brake mounting plate secured to the spindle and adapted to support brake friction pads. The preassembled spindle and brake assembly further includes a plurality of inwardly extending vehicle mounting lugs carried by the spindle, and a plurality of outwardly extending wheel mounting lugs carried by the rotatable component. Next, the preassembled spindle and brake assembly is positioned on a vehicle component such that the vehicle mounting lugs extend through a plurality of corresponding lug receiving apertures formed in the vehicle component. The preassembled spindle and brake assembly can then be secured relative to the vehicle component.

Abstract: This invention relates to a cable actuated parking brake mechanism for a drum brake. A lever and an associated lever return spring are arranged to accommodate blind assembly of the cable to the lever. The spring guides the cable from an opening in the backing plate to the lever. The spring cooperates with the lever to indicate to an assembler that the cable is fully inserted as well as aids in directing a cable button to an engagement surface.

Abstract: A drum brake (10) includes a backing plate (11) supporting a pair of drum brake shoes ( 12, 14) having brake shoe webs (16, 18). An opposing pair of brake shoe ends (26, 28) have adjacent thereto a combination drum brake shoe hold-down bracket and cable guide (60) attached to the backing plate (11) . The hold-down bracket and cable guide (60) has a pair of securement portions (61) extending laterally or transversely, via axial projections (62) and ends (64) , relative to the center of revolution (A) of the drum brake (10) and which engage the drum brake shoe webs (16, 18) to assist in maintaining the brake shoes (12, 14) in operative position. Each portion (61) of the hold-down bracket and cable guide (60) extends laterally toward one another via an axially extending portion (65) that curves in an annular path to form a center portion (67) that defines a cable guide path (68).

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: A dual mode drum brake assembly having an improved duo-servo parking and emergency brake lever mechanism includes a pivot lever pivotally supported relative to a first brake shoe and operatively coupled to exert an outward force on the first brake shoe when the parking brake is actuated. According to one feature of the invention, a hold down assembly extends through an aperture formed in a web of the first brake shoe, and through an aperture formed in the pivot lever to secure the first brake shoe to a backing plate and to pivotally connect the pivot lever to the web. According to another feature of the invention, an adjuster lever of a first strut member is pivotally supported on the first brake shoe, and the pivot lever is pivotally supported on the first brake shoe generally intermediate the first strut member and a second strut member.

Abstract: The automatic adjuster (5) for the drum brake (6) comprises first and second oppositely disposed end members (30, 40) each having slots (32, 42) for receiving nonrotatably brake shoe webs (10, 14) and a parking lever (22). The first end member (30) includes a radially expanded end portion (34) defining an interior cavity (36) with a conically shaped surface (38). The second end member (40) is connected with a rotatable starwheel flange (44) of a longitudinally extended shaft (48) having therein a threaded opening (49), the starwheel flange (44) immobilized by a return spring (16) of the brake (6). An intermediate member (50) has at one end a threaded shaft (52) which is received threadedly within the threaded opening (49) of the shaft (48) and at the other end a conically shaped member (54) which engages the conically shaped surface (38) of the first end member (30).

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 flat lever (314) for use in a blind-cable-connection parking brake system is formed by stamping from sheet steel stock. At one end, the lever is adapted for pivotal connection with a backing plate, and at its other end, the lever is stamped to defined opposed spaced inclined ramp (314a) and helical guide spring support (314b) portions integral with the lever. In order to properly orient the guide spring relative to the ramp, the guide spring support includes a support ledge (314d) for supporting one end of the spring (320) relative to a spring-receiving opening formed in the guide spring support portion.

Abstract: A parking brake system comprising a drum brake (200) comprising two shoes (206) outwardly movable relative to a friction surface of a drum (224); an activation device (220, 222) for generating an activation force to move the shoes outwardly to a first position into contact with the drum sufficiently to prevent the drum; a solenoid activated linkage mechanism (230, 240; 322, 352) is provided for maintaining the shoes substantially in the first position.

Abstract: A drum brake in which a parking brake is incorporated. A parking brake lever is mounted in the interior of a vehicle and is operable to pull a parking lever through a cable. The rotation of the parking lever causes a pair of brake shoes to be forced tightly against a brake drum. This results in the generation of a braking force. A stopper member is provided to limit the maximum angular position of the parking brake. This design prevents contact of the parking lever with a rotary shaft due to excessive pulling of the parking lever and thus damage of the rotary shaft as well as the parking lever.

Abstract: A drum brake assembly wherein the hydraulic service brake acts as a leading/trailing brake and the parking or emergency brake acts as a duo-servo brake. A lever member is pivotally mounted on one of a pair of brake shoes and operated by a brake actuating lever pivotally mounted on a composite link disposed adjacent a rotation-preventing stop and operatively connected to the other of the brake shoes. The lever member acts on another composite link disposed adjacent a hydraulic actuator of the service brake and operatively connected to the other of the brake shoes.

Abstract: An anchor bracket (100) is provided for securing return springs (36) and (36') in close proximity to a cam (32) of a rotary drum brake assembly (200). Bracket (100) has an inverted "U" type configuration comprising a bridging portion (40) from opposite sides of which extend legs (42) and (42') that are spaced apart from each other and have a height sufficient to enable the close proximity between cam (32) and bracket (100) that operates to increase mechanical advantage in enabling return springs (36) and (36') to move a pair of brake shoe assemblies (20) and (20') towards each other upon release of the brakes by an operator.

Abstract: A self-adjuster for a drum brake of the leading-trailing or duo servo type having the adjuster lever mounted on one of the brake shoe webs and engaged in as separate slot on the spreader and adjuster strut from the slot in which a brake shoe web and a parking brake actuating lever are received, preventing the adjuster lever from being jammed by the brake shoe web or the parking brake actuating lever. The pivot point for the adjuster lever is the same as that for the parking brake actuating lever, and is a pin mounted on the brake shoe web which is received in the other adjuster strut slot with the parking brake lever.

Abstract: A drum brake in a motor vehicle, comprising a parking brake which includes a brake cable connected detachably to a hand brake lever arranged in the drum brake by the brake cable being passed through a retaining member which is connected to the hand brake lever an engaging behind the retaining member by a nipple of larger cross sectional dimensions connected to the corresponding free end of the brake cable is characterized in that the brake cable (6) is passed through a guide tube (7) which is fixed to the anchor plate (1) of the drum brake, is exposed to the outside of the drum brake, and terminates at a distance ahead of the retaining means (8), the inner diameter of the guide tube (7) being somewhat greater than the maximum outer diameter of the nipple (9), in that the retaining member (8) has a guide path (10) for the nipple (9) extending from its front face (11) which faces the guide tube (7) to its rear face (12), and in that rear face ( 12) of the retaining member (8) is provided with a locking member (

Abstract: The invention relates to a drum brake with two shoes, each having a web (16) and a rim (18), of which the face confronting the drum receives a friction lining (20). The drum brake is arranged on a supporting plate (10) and also includes a mechanical control lever (34) comprising a body of considerable length and of small thickness in relation to its width, the body having, at a first end (36), an orifice (38) intended for receiving an articulated connection with the web (16) of one of the shoes (14) at an intermediate point near the orifice, and a notch intended for interacting with a spacer (62) making it possible to subject the shoes (12, 14) to a stress moving them away from one another, and at the second end (40), a fastening point for an actuating cable (54) of the lever. The cable is equipped with a ferrule (60) at its end interacting with the lever.

Abstract: A drum brake assembly having a parking brake actuating lever is so arranged that the parking brake cable end may be assembled in a blind fashion to the end of the actuating lever. The cable is provided with an enlarged end or button. The cable and spring are inserted through a guide tube and pushed inwardly into the brake assembly with the guide tube or a combination of the guide tube in a separate spring guide placing the cable button in a alignment so that it is aimed at a funnel-like guide and retention member formed on the end of the parking brake actuating lever. Further axial movement of the parking brake cable and its enlarged end result in a camming action which moves the enlarged end upwardly through and beyond the slot after which it snaps back downwardly to be positioned to be able to apply cable tension forces to the parking brake actuating lever.

Abstract: A drum brake assembly having a parking brake actuating lever is so arranged that the parking brake cable end may be assembled in a blind fashion to the end of the actuating lever. The cable is provided with an enlarged end or button. The cable and spring are inserted through a guide tube and pushed inwardly into the brake assembly with the guide tube or a combination of the guide tube and a separate spring guide placing the cable button in alignment so that it is aimed at a funnel-like guide and retention member formed on the end of the parking brake actuating lever. Further axial movement of the parking brake cable and its enlarged end result in a camming action which moves the enlarged end through a one-way snap connection so that the cable is able to apply cable tension forces to the parking brake actuating lever.

Abstract: A parking brake assembly of the blind-cable-connection type including a backing plate containing an opening, a helical guide spring arranged to guide a flexible resilient inner cable member toward a ramp surface on a parking brake lever for the blind connection to the inner cable member to the lever, characterized in that the angle of inclination of the ramp surface relative to the cable axis is contained in a plane that is both parallel with the longitudinal axis of the lever and that is inclined at an acute angle relative to the axis of the inner cable member. This construction permits the parking brake lever to be simply and economically formed from a blank of flat metal stock, the cable-retaining slot being defined by a slot contained between bifurcated portions of the ramp surface. The helical guide spring includes portions having tightly wound turns, thereby to assist in connecting the spring with the backing plate and/or with the parking brake lever.

Abstract: A drum brake assembly having a parking brake actuating lever is so arranged that the parking brake cable end may be assembled in a blind fashion to the end of the actuating lever. The cable is provided with a button. The lever has a return spring which has one end attached to the lever and the other spring secured to the backing plate about a parking brake cable opening through the backing plate. The spring end attached to the lever has a retaining ramp and a hook end, the retaining ramp being above an open channel formed on the lever end and the hook end being secured to the lever one end above the channel. The cable button is inserted axially through the backing plate opening provided for the cable and through the spring, being guided by that spring, to a point above the channel open receiving end.

Abstract: A drum brake assembly having a parking brake actuating lever is provided so that the parking brake cable end may be assembled in a blind fashion to the actuating lever. The cable is provided with a button. A spring is attached to the lever and to the backing plate about a parking brake cable opening. The spring end attached to the lever has a ramp section and a hook end, the ramp section being in a tapered open channel formed on the lever end and the hook end being secured to the lever. The cable button is inserted axially through the backing plate opening through the spring, being guided by the spring, into the channel. Further insertive movement of the cable button causes the button to be deflected upwardly by the coil spring ramp portion and the channel sides, side loading the cable. When the button passes the end of the ramp portion and the channel smaller end, the stored force in the cable because of the side loading moves the cable and the button downwardly in the channel.

Abstract: A parking brake assembly of the blind-cable-connection type including a backing plate containing an opening, a helical guide spring arranged to guide a flexible resilient inner cable member toward a ramp surface on a parking brake lever for the blind connection to the inner cable member to the lever, characterized in that the angle of inclination of the ramp surface relative to the cable axis is contained in a plane that is both parallel with the longitudinal axis of the lever and that is inclined at an acute angle relative to the axis of the inner cable member. This construction permits the parking brake lever to be simply and economically formed from a blank of flat metal stock, the cable-retaining slot being defined by a slot contained between bifurcated portions of the ramp surface. The helical guide spring includes portions having tightly wound turns, thereby to assist in connecting the spring with the backing plate and/or with the parking brake lever.

Abstract: A brake system for a motor vehicle having three sources of communicating pressurized fluid to wheel brakes and having a mechanical brake. Two of the sources of communicating pressurized fluid are the reservoirs of a dual master cylinder and provide first and second hydraulic brake subsystems. The remaining source is an emergency master cylinder and provides a third hydraulic brake subsystem. The mechanical brake and the third hydraulic brake subsystem are operatively connected to an emergency brake pedal. Disc brakes each have a pair of floating calipers, each caliper being in fluid communication with a pair of sources of communicating pressurized fluid. Drum brakes have at least one dual chambered wheel cylinder in fluid communication with two sources of communicating pressurized fluid. The first and second hydraulic brake systems, as well as the emergency brake pedal, operate brakes on each of the four wheels of a motor vehicle.

Abstract: A drum brake comprises two brake shoes (4,5) which are operable hydraulically and/or mechanically. A first brake shoe (4) is supported trailingly in forward travelling direction and leadingly in backward travelling direction. In the forward travelling direction both brake shoes (4,5) are supported trailingly so as to obtain soft response behavior. And a lever (7) is supported at the second brake shoe (5), having one arm pressurized by the piston (2) of the wheel brake cylinder (1), while the other arm (7b) acts directly or indirectly on the first brake shoe (4).

Abstract: The assembly spring consists of a V-shaped elastic metal wire (R1), one end of one branch (61) of which forms a hook (71) which ensures the retention of the pivot (52) of the lever (50), the branch (61) passing through a passage (81) provided in a spacer (44), in order to stress it elastically toward the lever (50) in interaction with the other branch of the V (91) which has a mechanism (101) of anchoring on the web (18) of the shoe (14) carrying the lever (50). The anchoring mechanism consists of a wire portion (101) bent at 90.degree. relative to the plane of the V and interacting with the web (18) of the shoe (14) and the lever (50) adjacent it, to constitute a mechanism forming a stop. The invention is used for the braking of vehicles.

Abstract: A mechanically-operated drum brake device which comprises a pair of brake shoes each coming in contact with an anchor at one end portion on the same side and engaging with a floating type actuator and a brake lever rotatably supported on the actuator at their other end portions, respectively. There is provided structure for holding in place the brake shoes and the actuator relative to a back plate at a predetermined distance therebetween in the axial direction of a brake drum. There is also provided a stop member to control the inward contracting movement of the brake shoes when the brake is released.

Abstract: The present invention provides an apparatus and method of utilization of the same of a brake spring support. The support of the present invention provides a head for locating and supporting the spring along with a fixably connected curved tang which is inserted into an aperture of the brake shoe and is cammingly locked to the brake shoe after attachment of the spring.

Abstract: A parking brake assembly comprising a pair of brake shoes pivotally mounted on a backing plate, a brake operating lever pivoted to the brake shoe and operable by a remote cable for pivoting the brake shoes against a brake drum, and a coil spring provided under compression between the brake lever and the backing plate. During shipment of the parking brake assembly, it is attached to an axle and the coil spring has an end that extends to an opening in the back plate. The cable including a conduit and an inner member, preferably a flexible strand, is handled separately. After the parking brake assembly is attached to an automotive vehicle, the cable can be connected even though the brake drum is in place and prevents seeing the interior of the brake assembly. Specifically, the strand is then forced through the conduit and the coil.

Abstract: A self adjusting wheel cylinder for a drum brake including a brake drum and a brake shoe for exerting braking pressure on the drum with a shoe gap formed therebetween comprising a cylinder including an opening therein, hydraulic piston slidably mounted in the opening for activating the brake shoe upon movement in one direction, and for releasing the brake shoe upon movement in the other direction, and multiple adjusting screws within the cylinder for automatically adjusting the limit of movement of the piston in response to changes in the shoe gap of the brake, the multiple adjusting screws including a spindle having external screw-threads on both ends, the spindle is threadably mounted within the piston to one end thereof, and has a pair of multiple drive screws on the other end of the spindle for defining a fixed movement limit of the piston.

Abstract: In a drum brake including three brake shoes (4,22,23) adapted to be pressurized hydraulically and/or mechanically first and second hydraulically operable brake shoes (4,22) are supported trailingly in forward travelling direction (21), while the third brake shoe (23), together with at least one of the other brake shoes (4,22) is pressurized upon mechanical braking such that one each of the brake shoes (23 and 4 or 22) is supported trailingly and one is supported leadingly, both in forward and backward travelling directions.

Abstract: The invention concerns the construction of a blank with a view to manufacturing a handbrake control lever (34) for a drum brake. The blank defines two fingers situated essentially at the extension of the body of the blank, one of the fingers is to be folded back to form a trough (62) to accept a cable, the other finger is to be positioned relative to the trough (62) so as to prevent the cable from escaping from the latter.

Abstract: Herein disclosed is a cabling structure of a parking cable for a drum brake which is equipped with a backing plate, a brake shoe and a parking lever. A pulley is hinged in a swinging manner to the backing plate or the brake shoe and is formed with two arcuate grooves having different radii measured from the hinging axis. First and second cables are hung in the two arcuate grooves, respectively, and are connected to a brake actuating mechanism and the parking lever, respectively. The direction of leading out the parking cable can be different from that of the force for pulling the parking lever without any breakage of the parking cable. The pulley may alternatively be formed with one arcuate groove. Then, the second cable connected to the parking lever is retained on the pulley such that it extends to partially contact with the first cable.

Abstract: A recentering device for a drum brake is provided in an opening of the strut placed between the shoes and includes a spring placed between two cups which are capable of sliding in the opening and both engage a fixed bearing element on the brake support plate and are supported by one of the shoulders formed in the opening. During braking, the strut compresses the spring through one of the two cups by way of the corresponding shoulders. On termination of braking, the spring recenters the strut, driving it back until one of the cups regains its bearing on the associated fixed bearing element, thus recentering the shoes bearing on the strut.

Abstract: A hydraulic wheel cylinder assembly is particularly for use in a drum brake of the kind in which the wheel cylinder assembly is interposed between one pair or adjacent ends of a pair of brake shoes and a mechanical expander and fixed abutment is interposed between the other pair of adjacent ends of the shoes. The wheel cylinder assembly incorporates a pair of piston assemblies each including an adjustable variable length tappet assembly comprising rotatable and un-rotatable screw-threaded components. The rotatable screw-threaded component can move axially relative to the driven member of a one-way drive mechanism by compression of a spring when a flange on the driven member strikes the wheel cylinder body. This provides a self-centering force which prevents drag when the brake is installed with the shoes one above the other.

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 drum brake (10) includes a light-weight backing plate (12) which carries a pair of brake shoes (44, 46). The backing plate comprises a pair of stamped plates (18,20) having a plurality of radially extending arms (22-28) which cooperate to guide the brake shoes. A hydraulic actuator (68) is carried by the brake shoes to move the shoes into engagement with a brake drum (66). A light-weight dust shield (82) cooperates with the brake drum to inhibit the entry of dirt into the brake. The actuator (68) carries a parking lever (94) and cooperates with the lever to effect a parking brake application responsive to pivoting of the lever. An adjustable strut (62) spaces apart the brake shoes. An automatic adjusting mechanism (106) cooperates with the strut to maintain a substantially constant running clearance between the brake shoes and the brake drum.

Abstract: An internal shoe-drum brake is disclosed in which a pair of arcuate shoes can be applied to a rotatable drum by an hydraulic actuation system for normal service braking when the brake acts as a brake of the "two-leading" shoe type and a mechanical actuation system for parking or emergency braking when the brake acts as a brake of the "duo-servo" type. The hydraulic system comprises two hydraulic pistons, each of which acts on the leading end of a respective shoe, and first and second abutments are provided against which the trailing ends of the shoes are adapted to rest. One abutment is fixed but the other abutment includes an auxiliary hydraulic piston which is adapted to be urged against a fixed stop by hydraulic pressure applied to the pistons. The reaction from the trailing end of a respective shoe tends to urge the piston away from the stop, but the area of the piston is sufficient to prevent this happening when the hydraulic pressure is acting on the piston.

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 duo servo drum brake includes a pair of brake shoes which are movable by a hydraulic actuator during a service brake application to a braking position in engagement with a rotatable member. A strut and parking lever are engageable with respective brake shoes to separate the same during a parking brake application. In order to control a running clearance between the pair of brake shoes and the rotatable member, an extendible assembly is disposed between the pair of brake shoes opposite the hydraulic actuator. The extendible assembly is also responsive to a parking brake application to expand the pair of brake shoes into engagement with the rotatable member.

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 includes a pair of brake shoes which are carried by and pivotally anchored to a backing plate. The pair of shoes are engageable with a brake drum to effect a brake application. A running clearance is maintained between the brake shoes and the drum when the brakes are released by an adjusting member which includes an adjusting lever pivotally carried by one of the shoes and a fixed-length spacer carried between the adjusting lever and the other brake shoe. An extensible member is carried between one end of the adjusting lever and the one brake shoe and a three-bar linkage effects an extension of the member to compensate for wear of the brake shoes. The adjusting lever forms one bar of the linkage and carries the other two bars. The second bar of the linkage is pivotally engaged with the adjusting lever and with the spacer and is biased so as to move the spacer away from the adjusting lever during a brake application.

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 drum brake assembly includes a backing plate for supporting a pair of brake shoes and a hydraulic actuator which cooperates with the pair of brake shoes to urge the latter into a braking position. A parking lever is pivotally mounted on one of the brake shoes and a strut connects the parking lever with the other brake shoe such that rotation of the parking lever when the parking brake is applied urges the pair of brake shoes into a braking position. In order to connect the strut to the other brake shoe while at the same time eliminating any rattle between the pair of brake shoes and the struts, a spring clip releasably connects with the other brake shoe and resiliently engages the strut to bias the latter toward the one brake shoe. The spring clip is substantially U-shaped with at least one opening for receiving the strut and for maintaining the strut in juxtaposition to the other brake shoe.

Abstract: A drum brake includes a pair of brake shoes and a hydraulic actuator which is engageable with the brake shoes to expand the latter during braking. The hydraulic actuator carries a pair of elastomeric sealing rings which are deformable during braking as a pair of pistons slidably disposed with the hydraulic actuator are movable upon a braking application. When braking is terminated, the elastomeric sealing rings return to their original stored configuration thereby retracting the pair of pistons within the hydraulic actuator. In order to retract the pair of brake shoes with the pistons through a predetermined distance, a first spring engages the pair of brake shoes substantially opposite the hydraulic actuator and biases the brake shoes toward each other while a second spring biases the brake shoes away from each other. The second spring is carried by a strut on a parking brake actuator and the strut extends from one of the brake shoes to a lever which is pivotally mounted on the other brake shoe.

Abstract: An improved adjuster for a shoe drum brake comprising a strut of adjustable length extending between one of the brake shoes and an arm of an operating lever that is actuated by a hand brake. The strut has a threaded part or spindle and a ratchet threadedly engaging with the threaded part. The adjuster also comprises a pawl arm carried by the arm of the operating lever and having a pawl cooperating with the ratchet. The arm of the operating lever is formed with a nose positioned for engagement with the other one of the brake shoes. The threaded part of the strut is formed with a stopper which is adapted to engage with the ratchet to define the minimum length of the strut.

Abstract: An improved and reusable stop assembly is provided for employment in drum brakes of the type having an internal lever operably coupled with the brake shoes for actuating the brake from a standby, partially retracted, relative position of the brake shoes to a position in which the shoes are spread apart to apply braking forces to the drum. The improved stop assembly includes a guide sleeve part mounted on the backing plate of the brake and a freely slideable and removable stop member receivable therewithin. When the stop member is inserted into and locked within the sleeve assembly, its inner end engages the lever to hold the shoes in their standby, partially retracted, relative positions against the forces of yieldably biasing means conventionally coupled with the shoes.