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: A linkage for connecting a brake cable to an actuator lever in a drum-in-hat park brake assembly. The linkage is defined by a continuous wire that is shaped into a base with parallel and adjacent first and second legs located in a first plane perpendicular to the base and parallel and adjacent third and fourth legs located in a second plane perpendicular to the base. The first and second legs each have a first section that extend a first distance from the base to a first loop and a second section that extend a second distance from the first loop to a second loop while the third and fourth legs extend a third distance from the base. The base has an opening defined by a complementary shape created between the first leg and the third leg and the second leg and the fourth leg.

Abstract: A brake cable connecting apparatus of a brake-actuating mechanism for a drum brake is mainly composed of a brake lever (22) and a strut (21). A cable end (24a) of a brake cable (24) is snapped into a free end (22e) of the brake lever (22) when the brake cable (24) is pulled in the cable operating direction against a spring force of a return spring (15) and disassembled therefrom when the brake cable (24) is removed from the free end (22e) while the brake lever (22) is pressed by a tool (30). A guide section (22h), for supporting a top of the tool (30), is formed on the brake lever (22) at a side relative to the cable releasing direction.

Abstract: A drum brake having a disc with a peripheral surface with a plurality of radial guides interspersed between a first radial abutment and a second radial abutment. The plurality of radial guides receive a first arcuate channel member on a first brake shoe and a second arcuate channel member on a second brake to align a first reaction surface on the first channel with the first radial abutment and a second reaction surface with the second radial abutment. An actuator provides a force to move the first reaction surface moves away from the first radial abutment and the second reaction surface from the second radial abutment to initiate a brake application.

Abstract: A brake cover (18) and shaft (24) rotate with a pedal lever (20) relative to a central section (14) of the housing (12) rotate a pedal gear (76). The pedal gear (76) rotates a sensor gear (74) to rotate a sensor arm (46) about a sensor axis (48). The sensor arm (46) supports sensor members (58) that move along sensor bands (50) to generate an electrical signal. As the brake cover (18) rotates with the pedal lever (20) it uncoils coil springs (84) to cause brake shoes (80) to pivot radially outward about respective posts (82) frictionally engage the interior surface (78) of the central section (14) to thereby provide a resistance or hysteresis to movement of the pedal lever (20).

Abstract: A parking brake device for a vehicle, including: (a) a backing plate which is fixed to a body of the vehicle such that the backing plate is held substantially perpendicular to an axis of a wheel of the vehicle; (b) first and second arcuate brake shoes which are disposed on one of opposite sides of the backing plate such that the first and second arcuate brake shoes are movable toward and away from each other; (c) a moving mechanism which is positioned between the first and second arcuate brake shoes and which includes a pivotable brake lever, the moving mechanism moving the first and second arcuate brake shoes away from each other when the brake lever is pivoted in a predetermined direction; and (d) an operable member which is connected to the brake lever and which is operable by an operator of the vehicle to pivot the brake lever in the predetermined direction, wherein the brake lever has a connected portion at which the brake lever is connected to the operable member, and wherein the brake lever extends thr

Abstract: A drum-in-hat park brake assembly for a vehicle wherein first and second brake shoes are retained and aligned on a backing plate by first and second pins. The first and second shoes are moved into engagement with a drum by a force applied to an actuator by a cable assembly. The backing plate is characterized by a flange having a slot therein and the cable assembly is characterized by a cable with a fitting on a first end that has a stem with an annular rib thereon. The stem passes is passed through the slot while the annular rib engages the flange to limit the movement of the first end of the cable toward the actuator and to limit the movement of the first end toward the actuator mechanism to prevent the lever from being axially moved past a position of rest and change the radial alignment between the first and second brake shoes and the backing plate by the action of a release spring.

Abstract: A brake cable connecting apparatus is structured to prevent the inadvertent disengagement of a cable end from the brake lever while transporting a drum brake. The bridge portion (11e) of the strut (11) extends above the free end (12e) of the brake lever (12) leaving a clearance (23), being smaller than the cable end (16a), therebetween. When the brake lever (12) rotates to the predetermined degree, the clearance (23) becomes larger than the cable end (16a) so that the cable end (16a) is able to pass through the clearance (23) between the bridge portion (11e) and the free end (12e).

Abstract: A drum brake device prevents shoe clearance over-adjustment by means of a thermo-sensitive member with a lower leg opening force and provides a smaller thermo-sensitive member with a lower cost. A portion between both ends of the brake lever (50) in a direction of crossing the shoe return inhibitor (61) engages with one end of the shoe return inhibitor (61) automatically restricting the return position of the pair of brake shoes (20) and (30); the proximate portion (50a) of the brake lever (50) is pivotally supported on the brake shoe (20); and the free end (50b) side of the brake lever (50) is supported at the brake shoe (20) via the thermo-sensitive member (70).

Abstract: The improved drum brake includes an anchor plate, a drum, and a drum ring and brake shoes, which cooperate with the drum and are disposed in a drum chamber between the anchor plate and the drum, and ventilation openings on the drum.

Abstract: A method of attaching a brake cable assembly onto a drum brake assembly is disclosed for a new form of brake cable having a cable inner portion with an end fitting and a cable outer portion comprising a cable sheath and a guide. The cable guide is inserted through a hole in a backplate of the brake assembly and positioned such that an open end of the guide is presented adjacent an automatic latching device on a parking brake lever of the brake assembly. The cable inner is then advanced through the cable outer such that the end fitting is guided towards, and engages the automatic latching device. The cable outer and backplate may be provided with corresponding orientation features which are aligned to ensure the correct presentation of the open end of the guide adjacent the latching device during assembly. These orientation features may take the form of interengaging formations on the backplate and cable outer. The guide may include a spring which acts as a return spring for the parking brake lever.

Abstract: This invention is a new type of drum brake and its variants for motor vehicles, the shoe mechanism assembly of which has at least one set of interconnected shoe mechanism and automatic adjusting mechanism of brake clearance. The interconnected shoe mechanism consists of two interconnected composite shoes of multiple degrees of freedom. Each composite shoe consists of a shoe and a driving lever. The shoe is jointed to the driving lever with a cylindrical pin or a elliptical pin matching with a cylindrical hole or a spherical joint, and the driving lever is pivoted on the backplate of brake with a cylindrical pin or a elliptical pin matching with a cylindrical hole or a spherical joint. The automatic clearance adjusting mechanism is fixed on the backplate and interconnected with the driving lever.

Abstract: A brake cable for a dual mode type drum brake functioning as a leading-trailing type during the service brake and as a duo-servo type during the parking brake, may be easily arranged at a lower side of axle. The first and second brake levers (118), (119) of a parking brake actuator (117) have proximal portions (118a), (119a) pivotally supported between two ends of a second brake shoe (3) and at a lower end thereof; free ends (118b), (119b) extend in opposed direction from the proximal portions (118a), (119a) in parallel to face and functionally engage each other; a strut (120) extends between the second brake lever (119) and the pivot lever (16); and a brake cable (23) pulled to activate the free end (118b) is arranged adjacent to the anchor (7).

Abstract: A drum brake device having a brake lever with sufficient rigidity, and securing a larger space at a central region of a brake in order to provide a long, effective brake lever stroke. A by-pass hole 60d, through which the shoe-hold pin 41 swingably rising from the back plate penetrates, is formed in the brake lever 60 positioned beneath the shoe web 20b of the brake shoe 20, and the bending sections 60e, 60f, 60g are integrally formed toward the back plate 10 at the outermost circumferential edge portion of the brake lever 60 surrounding the by-pass hole 60d.

Abstract: A load adaptive brake system is provided for an appliance which includes a motor, a drive wheel driven by the motor and a rotatable vessel. A brake surface is fixed relative to a non-movable portion of the appliance and at least one brake shoe carried by the vessel to rotate with the vessel. A biasing mechanism is engageable with the brake shoe to press the brake shoe into engagement with the brake surface. A cam is carried on the vessel, but is rotatable with respect thereto, and engageable with a portion of the brake shoe to overcome a bias of the biasing mechanism when the cam is rotated relative to the vessel in a first direction to disengage the brake shoe from the brake surface.

Abstract: It is an object of this invention to provide a mechanical drum brake device which prevents a cable end from coming off from a brake lever without requiring an improvement in the brake shoe or the brake lever and an additional part. To that end, the lever return spring stretched between the brake shoe and the brake lever is utilized to restrict the lengthwise travel of the cable end along the shoe rim of the brake shoe.

Abstract: The present invention to provides a drum brake that generates the same braking force when a vehicle moves forward and backward. A first lever is connected to a second lever by a strut. A fourth lever provided with an anchor member and a third lever for connecting the fourth lever and the first lever to the end of the fourth lever) opposite to the anchor member across a screw which is the center of swing of the fourth lever. Accordingly, when the vehicle moves forward, an anchor load is received by the anchor member and the second lever. When the vehicle moves backward, the anchor load is received by the anchor member and the first lever.

Abstract: A shoe driving mechanism includes cam plates which respond to a shoe operating force to rotate about a main anchor pin on a back plate by a shoe operating force, and three pins consisting of an input pin, a secondary anchor pin and a primary anchor pin, which are uprightly disposed in a space between the cam plates. A secondary anchor pin and a primary anchor pin, respectively, expand a secondary shoe and a primary shoe by the rotating motions of the cam plates, caused by a shoe operating force. At forward braking and backward braking, those anchor pins cause rotation moments to act on the cam plates in such a direction as to lessen the shoe operating force in accordance with a braking force generated by each brake shoe.

Abstract: A mount bracket attached to a vehicle body is formed by pressing a metal plate to constitute a structure substantially in a shape of a flat plate having a circular plate portion overlapping a circular disc portion of a backing plate and a flange portion extended from an outer periphery of the circular plate portion as a portion attached to the vehicle body. A pair of brake shoes, a shoe drive mechanism and an anchor pin are constituted to be directly attached to the circular plate portion of the mount bracket without interposing the backing plate.

Abstract: A brake cable connecting apparatus is structured to prevent the inadvertent disengagement of a cable end from the brake lever while transporting of a drum brake without additional parts and damaging the cable end and the brake lever. That is, the bridge portion 11e of the strut 11 extends above the free end 12e of the brake lever 12 leaving a clearance 23, between the bridge portion 11e and the free end 12e, smaller than a diameter of the cable end 16a. Accordingly, even if the cable end 16a is about to be disengaged from the cable end engagement recesses 12g of the free end 12e, a further movement of the cable end 16a is prevented by cooperation between the bridge portion 11e and the free end 12e. Accordingly, if the amount of rotation of the brake shoe 12 is sufficient to fill clearances A1, A2 existing between the brake shoes 13, 14 and the brake shoe engagement groove 11a, 12b, the clearance 23 is still smaller than the diameter of the cable end 16a.

Abstract: A drum brake device having a brake lever with sufficient rigidity, and securing a larger space at a central region of a brake in order to provide a long, effective brake lever stroke. A by-pass hole 60d, through which the shoe-hold pin 41 swingably rising from the back plate penetrates, is formed in the brake lever 60 positioned beneath the shoe web 20b of the brake shoe 20, and the bending sections 60e, 60f, 60g are integrally formed toward the back plate 10 at the outermost circumferential edge portion of the brake lever 60 surrounding the by-pass hole 60d.

Abstract: A brake cable mounting structure for a drum brake, in which even if the distance from the brake mounting surface to the center of the brake shoes in the width direction is short, the layout of the brake cable mounting section and the mechanical expander is efficient and effectively provided. Further, the anchor only need to support the braking force, thereby making the device smaller and lighter. The brake cable mounting structure of this invention is characterized in that the inner cable of the brake cable extends out from the brake; and the guide pipe on which the outer casing of the brake cable is integrally fixed with the back plate.

Abstract: In a drum brake, a damper spring is provided for transmitting a shoe operating force outputted from a power lever to an input lever and for absorbing an impact force transmitted from brake shoes to the power lever via a link mechanism. The damper spring is mounted between the power lever driven by an electric motor of an operating force producing mechanism and the input lever of the link mechanism for receiving the shoe operating force outputted from the power lever for driving the shoes.

Abstract: It is an object of this invention to provide an automatic shoe clearance adjustment device for a drum brake mechanism designed to improve its durability by eliminating a gap, which is caused due to the manufacturing tolerances between the operating end surface of a brake shoe and the extended portion of an adjustment lever. To that end, a long hole (81) is formed to extend horizontally in the actuating direction of a service brake actuator (50); and the adjustment lever (80) is pivotally supported via a pin (14) with a capacity of making a rotation relative to the brake shoe (20) and a capacity of making a relative slide in approximately the same direction in which the service brake actuator (50) operates.

Abstract: A drum brake assembly (10) having first (12) and second (14) brake shoes retained on a backing plate (16). Each of the first (12) and second (14) brake shoes have an end (22,24) aligned on a hydraulic actuator assembly (26) and an end (28,30) aligned on an anchor block (40). An adjustable strut mechanism (32) has a extendable shaft (33) that includes a first end member (34) that engages the first end (22) of said first brake shoe (12), a second end member (36) that engages the first end (24) of the second brake shoe (14) and a rotatable stem (35). A first resilient member (150) urges the first (12) and second (14) brake shoes toward the hydraulic actuator assembly (26) and second resilient member (48) urges the first (12) and second (14) brake shoes toward the anchor block (40). The length of the extendable shaft (33) is adjusted by ratcheting a pawl (65) rotating the stem (35) to establish a predetermined running clearance between the first (42) and second (44) friction members and drum (46).

Abstract: The present invention relates to a magnetic adjustable loading wheel for an exercise apparatus, comprising a flywheel having a metal conductor fixed at the inner rim thereof; a stator disk disposed at the inner side rim of the flywheel; and a pair of resilient pieces mounted on the stator disk, a permanent magnet being fitted on the resilient piece.

Abstract: A dual mode drum brake device of this invention is subject to lightning and low-cost without over braking during the parking brake operation. Pistons 10, 11 in a cylinder device 9 push and rotate brake shoes 2, 3 to be separated apart around an abutment point with an anchor 8 during the service brake operation, thereby functioning as a leading trailing brake. An operation force W of the parking brake rotates a lever 14 in a counterclockwise direction around a pin 13, one end of the lever 14 rotates the brake shoe 3 outwardly around a protuberance 12a via the pin 13, and the other end of the lever 1 rotates the lever 12 in a clockwise direction via a strut 15 around the protuberance 12a to rotate the brake shoe 2 outwardly around the abutment point with the anchor 8 via the protuberance 12a.

Abstract: A shoe driving mechanism for a drum brake for pressing brake shoes against a drum is formed as an assembly in which the following are assembled to base plates which are rotatably fitted to an anchor pin for a primary shoe: an anchor pin for the secondary shoe; first and second lever supporting pins; a balance lever which is swingably supported by the first and second lever supporting pins whose distal-end side outer periphery is brought into contact with one end of the primary shoe; and an input lever for transmitting to the balance lever and the secondary shoe a shoe operating force inputted from an operating-force generating mechanism.

Abstract: A drum brake device which reduces the amount of non-effective stroke (play) and prevents noise for the long period of time. The first strut 12 of an automatic shoe clearance adjustment device is provided adjacent to the service brake actuator 8 and between both brake shoes 2 and 3. The parking brake actuator 19 is provided adjacent to the anchor block 9. The central region of the pivot lever 11 is rotatably supported with the central region of one brake shoe 2 as the fulcrum. Both ends of the pivot lever 11 functionally engage with the first strut 12 and the second strut 22 of the parking brake actuator 19 which comprises an automatic stroke adjustment device automatically adjust the stroke. When the brake shoes are opened by the service brake operation, one end 11c of the pivot lever 11 is elastically supported by the first strut 12 of the automatic shoe clearance adjustment device, and the spring applies spring force so that both pivot lever 11 and first strut 12 operate together with one brake shoe 2.

Abstract: A drum brake device including, a pair of brake shoes, a wheel cylinder, anchor pins, and a control lever. The control lever is disposed between a wheel cylinder and a secondary shoe and has a structure that the flanges and are raised from both ends of a plate-like lever body. The first flange is formed at one end of the plate-like lever body and includes a piston contact portion. The second flange is formed at the other end thereof. The surface of the second flange, which faces an anchor pin, is used as an anchor contact portion, and the surface of the second flange, which faces the secondary shoe, is used as a shoe contact portion.

Abstract: A drum brake backplate assembly including a wheel cylinder (30) having a tubular body (31) having an axially extending bore (32) within which two brake shoe operating pistons (33) are in sealed sliding contact to define a working chamber (48) therebetween. The pistons are displaceable away from each other along the bore on pressurisation of the working chamber and the body located on an associated brake-backplate (44) by quick-attach means (46).

Abstract: The present invention provides an improvement in an actuator system for use with a brake system of the type including a brake and a source of compressed air which is connected to an air chamber including a push rod for moving a transverse brake actuator bar between a brake applied position and a brake released position. The push rod operates the transverse brake actuator bar. The actuator system includes an asymmetric operator member which is relatively-rotatably-attached to a non-rotatable wheel support, and which is concentrically-disposed around an axle of a wheel. The asymmetric operator member includes an ear which is attached to the transverse brake actuator bar.

Abstract: A nestable cart, of the type guided by a walking attendant, for conveying a material such as luggage. The cart has a frame and is supported by two rear wheels and a front rotatable caster. A brake is contained within each rear wheel. The brake is automatically engaged when the cart is left unattended. Movement of the handle disengages each brake. A cable connected between the handle and brake linkage disengages the brake shoe, allowing each wheel to freely rotate.

Abstract: A parking brake having first and second brake shoes with a first end engaging an anchor post on a backing plate and a second end engaging an adjuster. An actuator located adjacent the anchor post has a first end that engages a first web on the first brake shoe and a second end the engages second web on the second brake shoe. A brake cable is connected to the actuator assembly for providing a force for moving the first and second brake shoes into engagement with the drum to effect a brake application. The actuator is characterized by a housing having first and second spaced apart walls with a first end and a second end. The first and second ends each have first and second ears with the first and second ears on the first end being joined together adjacent a central plane mid-way between the first and second side walls to establish a first slot that receives the first web.

Abstract: A drum brake device is provided which facilitates the pre-mounting of a long link, without increasing the number of components or the cost of the device. The long link (44) is pivotable on the central segment of one brake shoe (13). An engagement hook (48) protrudes from one or the other of the long link (44) or the one brake shoe (13). A notched groove (25) is formed in the other component thereof. The engagement hook (48) is inserted into the notched groove (25). The rotation of the long link (44) relative to the one brake shoe (13) will cause the long link (44) and one brake shoe (13) to be superimposable and detachable.

Abstract: A drum brake includes a first brake shoe, a second brake shoe and disposed opposite the first brake shoe within a brake drum, a backing plate supporting the first and second brake shoes, a wheel cylinder disposed between the first brake shoe and the second brake shoe, the wheel cylinder including a drive piston for pressing the first and the second brake shoes against an inner surface of the brake drum, a control piston for supplying hydraulic pressure in response to a braking reaction force from the second brake shoe, an anchor portion for receiving an anchor reaction force from the second brake shoe, a control lever for distributing the anchor reaction force to the anchor portion and to the control piston when the anchor reaction force reaches a predetermined braking force magnification, the drive piston has a base end in the pressure chamber and a leading end facing the first end of the second brake shoe and is movable to and from the second brake shoe by the hydraulic pressure supplied to the pressure cha

Abstract: A drum brake assembly as provided with a rack and pinion actuator. The rack and pinion actuator includes a pinion gear driving a pair of racks, with the racks driving the brake shoes into engagement with the brake drum. The pinion gear is provided with an adjustment thread which transmits rotation to an adjustment member. The adjustment member monitors the amount of rotation of the pinion gear during actuation, and a mechanism drives the adjustment member and the pinion gear back to its non-actuated position after completion of the braking cycle. The mechanism limits the amount of return movement of the pinion gear as necessary to provide adjustment of the brake stroke.

Abstract: Disclosed is a drum brake device in which during a service brake application, a pair of brake shoes operates in a leading/trailing mode, and during a parking brake application, a parking brake mechanism operates to cause the brake shoes to operate in the duo servo mode. A first lever, an equalizer and a second lever, which make up the parking brake mechanism, are all assembled onto one of the brake shoes. The second lever includes an input portion, a lever contact portion and an equalizer contact portion. The input portion receives a force from a parking lever. The lever contact portion applies a turning force to the first lever. The equalizer contact portion applies a turning force to the equalizer. The second lever, when it is turned, turns the first lever and then the equalizer.

Abstract: A parking brake assembly for a motor vehicle includes a lever acting against a brake shoe to urge the brake shoe into contact with a brake drum. The parking brake assembly includes a clasp pivotally mounted to the lever. The clasp includes a plate portion having a slot therein. The clasp pivots to accommodate blind assembly of the cable strand to the lever. Retention to the cable is accomplished by pivoting the clasp upward and out of the way while a bullet staked at one end of the cable strand passes through the slot. The clasp drops about the cable strand and a tensile force applied to the cable strand causes the bullet to engage the plate portion of the clasp to couple the cable strand to the lever.

Abstract: An improved bushing assembly for the outboard end of a brake cam shaft is provided with a bushing which establishes a grease flow pathway within the bushing assembly. Grease enters an aperture formed in a boss of the brake spider which holds the bushing through a grease zerk which is aligned with a first radial hole in the bushing, so the fresh grease injected goes directly to a grease reservoir between the bushing and the shaft. Flow channels provided in the bushing interior surface guide the grease around the shaft to a second radial hole which is diametrically opposite the first radial hole. Sealing means on the shaft restrict grease flow axially from the bushing along the shaft. Grease may be purged through the second radial hole to an annular space between a flanged inboard end of the bushing and the periphery of the aperture, from which the grease may exit. The flanged end of the bushing has tabs for engaging slots in the boss to align the bushing and to prevent rotation within the aperture.

Abstract: A drum brake device is provided in which a stroke before effectuating the parking brake effect of the brake shoes is restricted so that any disconcerting feeling to the driver and any delay in effectuating the parking brake when in an emergency situation are eliminated. The drum brake device includes a pair of the brake shoes 20, 21, a pivot lever 36 pivotally provided at one of the two brake shoes 21, a shoe clearance adjustment device provided between one end of the pivot lever 36 and one end of the brake shoe 20, and a strut provided between the other end of the pivot lever 36 and one end of the brake lever 28, wherein the braking force is transferable between the two brake shoes 20, 21 through the connection with the pivot lever 36. This produces a duo-servo type of brake device. The brake shoe 21 functions as a trailing shoe in which the lining wears slower when the service brake is in operation.

Abstract: A drum brake device is provided which facilitates the pre-mounting of a long link, without increasing the number of components or the cost of the device. The long link (44) is pivotable on the central segment of one brake shoe (13). An engagement hook (48) protrudes from one or the other of the long link (44) or the one brake shoe (13). A notched groove (25) is formed in the other component thereof. The engagement hook (48) is inserted into the notched groove (25). The rotation of the long link (44) relative to the one brake shoe (13) will cause the long link (44) and one brake shoe (13) to be superimposable and detachable.

Abstract: Within a wheel cylinder, a drive piston and a control piston, the base ends of which receives a hydraulic pressure from a master cylinder, are oppositely disposed while being axially aligned with each other. A primary shoe is pressed by the drive piston, and an anchor reaction force output from a secondary shoe is distributed to and loaded on an anchor portion and the control piston through a control lever. When the anchor reaction force reaches a predetermined value of force or larger, an anchor-reaction-force control link mechanism operates to move the primary shoe apart from a brake drum, thereby checking the increase of the anchor reaction force.

Abstract: A nestable cart, of the type guided by a walking attendant, for conveying a material such as luggage. The cart has a frame and is supported by two rear wheels and a front rotatable caster. A brake is contained within each rear wheel. The brake is automatically engaged when the cart is left unattended. Movement of the handle disengages each brake. A cable connected between the handle and brake linkage disengages the brake shoe, allowing each wheel to freely rotate.

Abstract: A wheel cylinder for expanding the opposed edges at one longitudinal end of a pair of brake shoes includes a pair of drive pistons for pressing the ends of the respective brake shoes under a hydraulic pressure supplied to the first pressure chamber, and a pair of control pistons which receive at the base ends the hydraulic pressure from the master cylinder and receive at the front ends anchor reaction force by way of levers, the control pistons being displaced to close a normally-open input control valve for supplying hydraulic pressure to the first pressure chamber when the anchor reaction force becomes larger than the hydraulic pressure received from the master cylinder by a predetermined magnifying power. Accordingly, it is possible to increase the stability of the braking effect of a duo-servo type drum brake.

Abstract: A drum-in-hat brake assembly (10) having first (12) and second (14) brake shoes retained on a backing plate (16) by first (18) and second (20) pins connected to the backing plate (16). The first (12) and second (14) brake shoes are aligned on the backing plate (16) by an anchor post (40) and connected to a reverse actuator (26). The reverse actuator (26) receives an input force to respectively move first (42) and second (44) friction pads associated with the first (12) and second (14) brake shoes into engagement with a drum (46) to effect a brake application. The reverse actuator (26) includes a first lever (52) and a second lever (54), each of which have a flat plate (60,76) that extends through an opening (62) in the backing plate (16). A resilient member (90) located in the opening (62) maintains the flat plates (60,76) in a same perpendicular plane with respect to the backing plate (16).

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: In order to improve an electrically actuatable automotive parking brake with mechanical emergency actuation, the brake pads (52, 54) of the parking brake, which may be either a disk brake or a drum brake, can be applied or released via gear arrangement (100) arranged within or at the brake. The gear arrangement (100) has one power input and one power output, with the power input being coupled with the one end of a flexible shaft, the other end of which being arranged remote from the brake can be coupled with a manual crank, in order to be able to actuate the parking brake mechanically in the case of a failure of the electric actuation.

Abstract: 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.

Abstract: Uniformly distributed compressive stresses are induced in the machined surfaces of brake drums and brake rotors. The compressive stresses cancel residual tensile stresses induced in the surfaces by machining operations during fabrication. Cancellation of the surface tensile stresses delays formation of cracks during service brake use and extends the service life of the brake drum or rotor. Shot peening is an applicable prestressing process which also imparts a surface roughness that reduces the time required to burnish brake pads to match the shape of the drum or rotor surface. The reduction of burnishing time reduces the amount of surface cracking caused by surface heating by brake pad high spots as the high spots are ground down.