Abstract: The present invention concerns a variable-torque braking device. The device is characterized in that it includes a secondary control (14, 17) which allows exertion on a friction-lining pad (9) of an additional moving-system braking torque as a function of a variable command parameter which exerts on the friction-lining pad (9) a movable-system braking force or torque capable of linear variation, in addition to the constant braking torque or force furnished by a main control, as a function of the variable control parameter. The invention finds an application notably to braking forklifts.

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 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 brake having multiple actuators is provided. In one embodiment the brake includes a torque transmission assembly centered about a longitudinal axis, a hub that is rotatable about the axis, and first and second pressure plate assemblies that are axially movable relative to the torque transmission assembly and each other. The brake also includes a drive plate assembly responsive to axial movement of the first pressure plate assembly for braking the rotation of the hub relative to the torque transmission assembly. Springs urge the second pressure plate assembly in a first axial direction towards the first pressure plate assembly and the first pressure plate assembly towards the drive plate assembly thereby setting the brake. One actuator is used to urge the second pressure plate assembly in a second axial direction, opposite the first axial direction and away from the first pressure plate assembly, to thereby release the brake.

Abstract: A motor vehicle parking brake system which is operated by non-muscular energy, includes both by a hydraulic pressure generator and by an electromechanical control unit. A control unit ensures that the switch between hydraulic and electromechanical operation is made as a function of the operating state of the vehicle.

Abstract: A braking device comprises first and second braking device respectively constrained to rotate with the brake case and with a brake shaft. The device comprises a braking piston, resilient device for displacing the piston axially towards a braking position, hydraulic device for displacing the piston axially in the opposite direction towards a brake-release position, and mechanical brake-release device for bringing the piston into its brake-release position and for holding it there. These mechanical brake-release device comprise at least two brake-release systems each comprising a bore having at least one substantially radial first segment, a screw displaceable in the bore, and displacement transfer device comprising at least one intermediate member suitable for transforming the radial displacement of the screw into axial displacement for pushing away the piston.

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 vehicle braking system that primarily operates as a pure brake-by-wire system, with optional hydraulic actuation. The system includes a set of four electrically actuated drum brakes. At least two of the wheel brakes include hydraulic actuators that operate to apply the wheel brakes independent of electric control. Each of the wheel brakes is normally operated in response to a control signal generated by the vehicle's brake processor. As such, a primary brake-by-wire system is provided at all four vehicle wheels. The rear brakes are proportioned to the front brakes electrically, according to design criteria.

Abstract: A drum brake device having a single brake shoe mounted to be movable on top of the back plate. One end of the brake shoe abuts against an anchor (10) and the other end interlocks with a shoe clearance adjustment device (14). A link (11) is supported so as to pivot in the central region of the brake shoe (3). One end of the link (11) is interlocked so as to be activated by a service brake actuator (12) itself activated when the service brake is applied, while the other end of the link (11) abuts against the anchor (10). When the brake drum is rotating in one direction, the other end of the brake shoe (3) is supported by the anchor (10), and when the brake drum is rotating in the reverse direction, the one end of the brake shoe (3) is supported by the shoe clearance adjustment device (14).

Abstract: A parking brake system for use on a railway car includes an actuator which is adapted to be attached to a service brake actuating lever arm of the railway car and to receive a flow of non-compressible holding liquid from a reservoir through a first valve unit. The first valve unit permits the liquid to freely flow to and from the actuator in a first position and only permits flow of the liquid towards the actuator in a second position. With this arrangement, movement of the service brake actuating lever arm automatically causes the actuator to be supplied with holding liquid from the reservoir, which liquid can be selectively retained by shifting of the first valve unit to the second position. Furthermore in accordance with the invention, the actuator can be shifted by supplying pressurized holding liquid thereto through the use of a motor driven pump circuit including a pressurizable reservoir.

Abstract: A brake system includes a pair of brake shoes and a wheel cylinder actuating the brake shoes such that the brake shoes contact a drum to apply braking action thereto. The wheel cylinder includes a housing, a first pair of oppositely facing pistons disposed within the housing, and a second pair of oppositely facing pistons disposed within the housing between the first pair of oppositely facing pistons. When the brake is operated, hydraulic pressure causes the second pair of pistons to move outward in opposite directions. As a result, the first pair of pistons move outward in opposite directions. Since the brake shoes are connected to the first pair of oppositely facing pistons, the brake shoes are applied to the drum. The wheel cylinder further includes a member disposed between and in contact with the second pair of oppositely facing pistons.

Abstract: A brake for a hoisting apparatus including a hoisting line, a drum for the hoisting line, a hoisting motor and a brake system for braking of the hoisting cable, the brake system consisting of a hydraulic brake and a mechanical brake. The mechanical and the hydraulic brakes are connected to a common transmission which is driven by the drum when this rotates freely, and the mechanical and the hydraulic brakes are controlled by a common controller for controlling the distribution of braking power between the two brakes. The control system distributes the braking power automatically between the brake systems. The transmission can also be connected to an autodriller for controlling the weight on the bit.

Abstract: A brake apply mechanism for a power transmission is provided which includes a planetary gear set having a ring gear member, a carrier assembly member and a sun gear member; an operator-controlled brake apply mechanism operatively connected to the sun gear member to selectively enforce rotation thereof; an auxiliary spring applied hydraulically released brake apply mechanism selectively operable to enforce rotation of the ring gear member to initiate brake engagement; and a brake apply mechanism operatively connected to the carrier assembly member to enforce brake engagement when either the operator control brake apply mechanism or the auxiliary brake apply mechanism is operated.

Abstract: ESTOP is a braking device causing a motorized vehicle, such as a snowmobile or ATV, to stop when the driver is ejected. When the ESTOP is armed, with a trigger pin attached by a tether and clip to a driver, the vehicle braking system functions normally. When the driver is ejected, removing the trigger pin, the ESTOP, unarmed, releases a force applying pressure, mechanically or hydraulically, to brake pads stopping the vehicle's brake rotor and bringing the vehicle to rest. Mechanically, ESTOP applies pressure from a released spring to brake pads on a caliper mounted on the vehicle's brake rotor. Hydraulically, the ESTOP applies pressure from a released spring to the vehicle's hydraulic brake system through a secondary master cylinder. ESTOP potential energy is not limited to a coiled wire spring, but may include a compressed gas canister, engine provided vacuum or an electrical solenoid.

Abstract: A transmission with built-in brake, particularly for vehicles, comprising an oil bath inside a containment and supporting casing, an epicyclic reduction unit kinematically connected to a power unit by means of at least two gears, of which the driven gear is axially fixed, coaxial to the sun gear and associated therewith by means of a splined coupling. A disk brake is arranged between the epicyclic reduction unit and the driven gear, so that at least one first disk is rigidly coupled to an internally-toothed ring gear rigidly coupled to the casing and so that at least one second disk is rigidly coupled so as to rotate together with the driven gear. The disk brake is associated with pusher means for packing that can move axially. Moreover, the pusher means comprise a flange, the piston of a fluid-activated actuator integrated in the casing acting on the flange. A pivot is rigidly coupled to the flange and protrudes from the casing. Respective actuation means act on the actuator and on the pivot.

Abstract: A drum brake including a carrier plate (10) on which there are slidably mounted first and second shoes (12, 14) capable of being brought into frictional engagement against an internal face of the drum (20) by a hydraulic actuation device (22). A variable-length strut (40) which, in interaction with a tension spring (30), determines the separation of the shoes (12, 14) and which is located in the vicinity of the hydraulic actuation device (22). A brace (100) is located on the web (14a) of the first shoe (14) and includes an active part (114) interposed retractable between the first end of the web (14a) of the first shoe (14) and one end (79) of the force-transmission actuation device (60, 70).

Abstract: An application device for a compressed-air-operated disc brake with a turn lever, an eccentric and two parallel male-threaded adjusting spindles, each of which acts via a pressure member on a brake pad and which are coupled together rotationally fixed via a synchronising device, in which an axially movable adjusting device is arranged to be integral in rotation in at least one adjusting spindle and, at every actuation of the turn lever, exerts an adjusting torque on the appropriate adjusting spindle which the synchronising device transmits to an adjuster or an actuator in the other adjusting spindle. The synchronising device is a shaft running in the region of the axis of the eccentric having a bevel gear on each face which meshes with a corresponding bevel gear of the adjusting device or the actuator.

Abstract: A device for actuating a piston located in a cylinder of a disk brake. A push rod translationally secured to the piston is connected to a lever through a ball joint. The lever extend through an elongated opening in an end member secured to the cylinder. The end member has an inclined plane which forms a cam surface with respect to an axial plane of the cylinder. A roller member attached to the lever engages the inclined plane at a single point of engagement. An input force applied to the lever causes the roller member to move on the inclined plane and impart pure axial translational movement to the push rod to correspondingly move the piston within the cylinder and correspondingly effect an actuation of the disk brake.

Abstract: A drum brake having a support plate (10) with first and second shoes (12,14) slidably mounted thereon. Each of the shoes (12,14) having a web (12a,14a) and a rim (12b,14b) with a face for receiving a friction lining (16,18). Each web (12a,14a) has a first end and a second end. The rim holds the friction lining in a position to engage a drum (20) in response to an input force applied to the first end of the webs (12a,14a) of the shoes (12,14) by a hydraulic actuation device (22). A bearing member (28) is secured to the support plate (10) and is connected to a second end of the webs (12a,14a). A spacer device (40) arranged in the vicinity of the hydraulic device has a variable length to establish a spacing between the shoes (12,14) and drum (20). A mechanical actuation device (50) secured to a web (14a) of shoe (14) has a first actuation lever (60) and a second lever (70).

Abstract: The drum-in-hat assembly (10) comprises a disc brake (12) mounted slidably relative to a backing plate (18) which includes an opening (19) through which extends a reverse scissors actuator (40) for the drum brake (30) of the assembly (10). The drum brake (30) includes a pair of arcuate drum brake shoes (32, 34) supported relative to the backing plate (18), with the shoes (32, 34) having a pair of opposed brake shoe ends (36, 38) engaged by the actuator (40). The actuator (40) comprises a pair of levers (42, 46) pivotably attached to one another with each lever (42, 46) having a second lever end (48, 58) engaging a respective end (38, 36) of an associated brake shoe, wherein the second lever end (48, 58) has either a slot (49) or an edge (59) located laterally away from the other and engaging the associated brake shoe end (38, 36). The actuator (40) is free to float relative to the backing plate (18), and the levers (42, 46) are located within a housing (70) attached to the backing plate (18).

Abstract: A pneumatically operated disk brake wherein a ball socket bearing at the connection of a lever arm to a compressed air cylinder's plunger arm of a caliper includes a slide bearing between the ball and the socket of the ball socket bearing whose sliding surface, consists of at least 70% by volume polyvinylidenefluoride, at least 10% by volume polytetrafluoro ethylene and a remainder of lead.

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: The present invention provides a disk brake including a cam shaft rotatably mounted on a cylinder portion of a caliper and having an end portion protruding from the caliper, a brake lever fitted to the protruding end portion of the cam shaft so as to rotate the cam shaft when the brake lever rotates, and a helical return spring disposed above a fitting portion of the brake lever fitted to the cam shaft and fitted around the protruding end portion of the cam shaft. The spring has one end secured to the caliper. The brake lever is provided with a plate-like vertical portion extending in the axial direction of the cam shaft from the fitting portion toward a tip of the protruding end portion of the cam shaft. The vertical portion is provided at one side thereof with a bent lug to which the other end of the return spring is secured. The bent lug extends away from the cam shaft.

Abstract: A brake application mechanism for a disc brake, particularly a sliding-caliper disc brake having an application shaft which extends parallel to the plane of the brake disc, wherein on the side of the shaft (8) which faces the brake disc (2) the shaft is supported against a thrust piece (9) which is movable against the brake disc (2), support being via a circularly arcuate first contour (17) which is rotatably mounted in a suitable bearing seat (18), and on the side of the shaft which faces away from the brake disc, the shaft is supported against an element with respect to which the thrust piece (9) is movable, support being via a second contour (21) which is eccentric with respect to the first contour.

Abstract: A disk brake having an electromagnetic friction clutch that can be brought into controllable frictional engagement with a brake disk. The friction clutch can act on a device for generating hydraulic pressure independent of the direction of rotation, and this pressure can act upon a clamping device for operating friction linings. To press the friction linings against the brake disk, energy is taken from the rotating vehicle wheel by means of the friction clutch and metered to the clamping device with pressure fluid as the energy carrier. The friction brake can be used in passenger cars, for example.

Abstract: An improved truck disc brake using a spring loaded safety brake and a pneumatic bladder for releasing the safety brake as well as a service brake enhancing bladder and at least a pair of rotor brake discs. The brake discs are ventilated and include ventilation channels extending radially thereof and vent air is deflected into the brake assembly by means of a scoop on the exterior of the housing passing through openings in the housing and the rotor brake discs act as an impeller moving the ventilation air rearwardly thereof to dissipate the heat. A wear gauge is provided to determine the wear of the brake linings and a quick release valve is mounted in the brake assembly adjacent the pneumatic bladder related to the service brake, to quickly release the air when required. Temperature sensors are provided within the brake assembly to read the temperature of the brake assembly.

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 mechanical/hydraulic brake system has an operator input pedal to initiate braking and brake cooling. The brake return springs establish a reaction force to provide the operator with a "brake feel" or feed-back force. The hydraulic apply forces have a tendency to reduce the feed-back force. A plurality of balance pistons are pressurized simultaneously with the hydraulic apply forces to maintain the feed-back force felt by the operator undiminished.

Abstract: A braking system for a vehicle. The braking system provides continuous tactile feed back through the brake pedal to the operator of the vehicle that conforms to the degree to which the vehicle brakes are being applied so that the tactile feed-back to the operator conforms to the visual and kinesthetic input received by the operator. The braking system has a brake pedal that is mounted to be depressed in response to a force applied thereto by the vehicle operator. The braking system incorporates both a mechanical brake actuating mechanism and a hydraulic brake actuating mechanism. The braking system provides for selective actuation of the mechanical brake actuating mechanism sequentially in advance of the hydraulic brake actuating mechanism when the brake pedal is depressed. A linkage assembly is incorporated in the mechanical brake actuating mechanism. The linkage assembly provides tactile feed-back to the brake pedal throughout the range of operation of said braking system.

Abstract: A drum brake assembly including a brake member comprised of a substantially circular shoe having a radially outer face on which at least one lining is mounted. The shoe is made from a high strength resilient material and is of substantially constant cross-section along its entire length. The brake member is arranged to be diametrically expanded by an actuation device on the brake assembly. When the actuation device is released the resilience of the shoe material causes the shoe to diametrically contract. The lining may be machined to a circular form prior to the brake member being fitted to the brake assembly, and that machining is preferably done after the shoe has been expanded a predetermined extent. The disclosure extends to a method of manufacturing a brake member and to a brake member for a drum brake assembly.

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: A disc brake caliper assembly for a rotary disc brake of a vehicle which has a wear adjustment mechanism is provided. The disc brake caliper assembly (10) includes a caliper housing (14) with a piston (28) slidably mounted therein, but prevented from rotating by a lug (30) on a brake shoe (16) secured thereto which keys in a groove (32) in the piston. An actuator screw (44) and actuator nut (66) are positioned in an internal bore (65) in the piston for mechanical actuation of the brakes. If the brake pads (20,22) wear, on hydraulic actuation of the brakes, a thrust washer (70) engages and moves the actuator nut axially along the actuator screw to a new position which restricts reverse movement of the piston to a new (wear adjusted) position relative to the caliper housing. An actuator cone (68) having a friction clutch surface biased into engagement with a friction clutch surface on the piston prevents reverse movement of the actuator nut.

Abstract: In a disc brake for a heavy road vehicle there is provided a mechanically preloaded brake assembly which includes a brake housing, a median wall in the brake housing parallel to the disc which is also in the housing. The disc is mounted to the adapter sleeve of the wheel, and the housing is mounted to an annular ring mounted to an axle of the vehicle. A pressure plate is provided within the housing and located between the annular intermediate wall and the housing wall opposite from the disc and is parallel thereto. The brake lining ring including a backing plate is provided adjacent a radial friction surface of the disc, and push rods extend between the pressure plate and the backing plate of the brake lining ring.

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 brake (10) capable of functioning as a disk brake and parking brake having engaged and disengaged modes of operation comprising: a piston rod (30) movable with the disk brake piston (14) having a threaded portion (40), a nut (60) rotatably movable on the threaded portion (40) relative to a first stop (52); a pressurizing device (80, 82, 84; 92) for pressurizing the fluid chamber (20) to move the piston (14) and piston rod (30) to respective engaged positions, and a motor (66, 68) for rotating the nut (60) in one of a) synchronism with pressurizing the fluid chamber and b) subsequent thereto so that the nut moves along the threaded portion (40) into a contracting position with the first stop (52) for preventing the piston rod (30) from moving from its engaged position to achieve the parking brake function.

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: The invention concerns a braking device with a piston that can be acted upon by a pressure medium from a pressure medium chamber against the force of a actuation spring. The piston is connected through an actuation arm with a brake linkage. In order to reduce the dimensions of the braking device, the actuation spring and the actuation arm are parallel and coaxial to each other, such that the actuation spring and the actuation arm are located between the moment arms of the brake linkage.

Abstract: A drum brake assembly having an automatic adjuster which adjusts the brake shoes for wear as needed during the service braking mode of operation. A spreader bar positioned between the brake shoes is capable of being acted upon by a parking brake actuating lever pivotally mounted on one of the brake shoes to transmit brake actuating forces through the spreader bar to one brake shoe and through the parking brake actuating lever to the other brake shoe to operate the brake assembly during the parking brake mode of operation. One end of the spreader bar is connected to the parking brake actuating lever to transmit tension force thereto during service braking apply, the other end of the spreader bar being connected to the other brake shoe so that service brake applying movement of that other brake shoe pulls the parking brake actuating lever to pivot it in the parking brake apply direction of lever movement.

Abstract: A one-piece casing (20) comprising a bottom (22) and a shell (24) formed with a cylindrical bore (26) houses a piston (30) for hydraulic actuation of a brake. For mechanical parking brake actuation, a shaft (34) is supported in the bottom (22) of the casing and a ramp arrangement (50) is rotatable by the shaft, thereby being displaceable axially away from a ramp arrangement (40) which is secured to the casing. Two strut members (60,64) which are screwed together constitute an adjustable strut between the axially adjustable ramp arrangement (50) and the piston (30). A return spring (90) is positioned under axial bias between a thrust bearing (92) secured to the casing and a thrust bearing (58) at one of the two strut members (60). The thrust bearing (92) which is secured to the casing is formed at an insert (84) by which one of the strut members (60) is guided non-rotatably.

Abstract: In a hydraulic drum brake and parking brake assembly, when a hydraulic actuator is operated to engage an opposed pair of brake shoes with a brake drum after a predetermined amount of wear had occurred on the friction pads of the brake shoes, a torsion spring adjusts a cam in the parking brake portion of the mechanism to compensate for the wear. The parking brake will thus operate properly despite the wear.

Abstract: A disc brake mechanism, including an integral mechanical parking brake assembly and having automatic wear adjustment features, is disclosed. The adjusting mechanism comprises an axial thrust screw having one end exposed to atmospheric pressure to create an axial hydraulic differential pressure acting thereacross. An adjusting nut is threadably received on the thrust screw and normally engages a hydraulic actuating piston such that the adjusting nut is free to rotate with respect to the thrust screw and piston. Hydraulic pressures acting upon the thrust screw create opposing forces, the resultant of which is applied to a resisting mechanical spring. So long as the hydraulic pressure is below a predetermined value, the resultant hydraulic force acting upon the thrust screw is insufficient to overcome the resisting spring force and the thrust screw remains stationary.

Abstract: The present invention involves an improvement in a conventional drum brake assembly which utilizes a pair of brake shoes separated by an adjustable strut. A parking brake lever is pivotally attached to one of the brake shoes and when it is rotated in a braking direction, causes both brake shoes to expand by interacting with the adjustable strut. A plate spring attached to a backing plate allows the parking brake lever to pass in the braking direction after assembly of the drum brake, thereby removing slack and properly adjusting the drum brake. The plate spring can be displaced from outside the drum brake to allow the parking brake lever to pass in the opposite direction for disassembly of the drum brake.

Abstract: A compound disc brake comprises a pair of pressure plates with a ball and ramp camming mechanism, one of the plates comprises a driven plate keyed to a rotating axle shaft to be braked, and the other plate comprises a servo plate carried from the driven plate by the camming mechanism. The servo plate has a torque-transmitting structure in the form of a separate annular disc keyed to the outer peripheral edge of the servo plate. The torque-transmitting structure transmits torque applied to that region by a primary braking apparatus to the central region of the servo plate. Retardation of the servo plate by the primary braking apparatus causes the pressure plates to separate axially and move into engagement with relatively stationary braking surfaces in the brake housing whereafter servo braking occurs.

Abstract: A brake actuator having a service brake coupled to an emergency/parking brake through a lost-motion connection that allows the service brake to be applied independently of the emergency/parking brake includes a slack adjuster, the pawl of which is withheld from engagement with the teeth of the slack adjuster ratchet wheel by an interrupter vane whenever the emergency/parking brake is actuated, to thereby disable the slack adjuster.

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: 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: An emergency or parking brake for motor vehicles equipped with a disc brake unit that can be provided with an actuating arrangement for disengagement and engagement of outboard brake pad structure against a rotor or disc sandwiched with respect to an inboard brake pad structure via a cam mechanism. In one embodiment the cam mechanism includes a camshaft that carries a cam member fixed thereto and pivotable by a lever spring biased in one direction although pivotable about an axis of the camshaft by a cable with a bifurcated member or fork attached thereto.

Abstract: In a disc brake for a heavy road vehicle there is provided a mechanically preloaded brake assembly which includes brake housing, a median wall in the brake housing parallel to the disc which is also in the housing. The disc is mounted to the adapter sleeve of the wheel, and the housing is mounted to an annular ring mounted to an axle of the vehicle. A pressure plate is provided within the housing and located between the annular intermediate wall and the housing wall opposite from the disc and is parallel thereto. The brake lining ring including a backing plate is provided adjacent a radial friction surface of the disc, and push rods extend between the pressure plate and the backing plate of the brake lining ring.