Abstract: A caliper is mounted on an axle casing of a rail vehicle by a first bracket and by a second bracket positioned between the disc and the first bracket. One of the brackets is detachably mounted on the casing and is removable to permit the caliper to be removed by movement in a generally axial direction. To permit this to happen the caliper and the other detachable bracket both lie outside the projected peripheral edge of a flange on the axle on which a wheel is mounted.

Abstract: A brake arrangement, especially a disk brake for vehicles, includes a brake caliper with brake pads guided on both sides of a brake disk which are operatively connected with hydraulically actuatable actuating pistons. Each actuating piston includes a bore directed toward the brake pad in which is arranged a cylindrically shaped insert number that includes a flange covering the piston end surface and is held with a radial and axial play with respect to the inner circumferential and bottom surface of the bore.

Abstract: A brake system of the type having a disc-type wheel brake hydraulically operated by a master cylinder through connecting lines is disclosed. The system includes a member which divides the wheel brake into two chambers, one adjacent to the brake piston filled with a hydraulic fluid specifically formulated for meeting certain expected operating conditions in the wheel brakes. The second chamber is connected to the hydraulic lines and is filled with a second fluid specially formulated for meeting certain other different expected operating conditions in the lines and master cylinder.

Abstract: In a piston-cylinder assembly for hydraulic brake systems of automotive vehicles, the piston is at least partially composed of ceramics. A hydraulic seal is interposed between the piston and the cylinder. To simplify the assembly while allowing comparatively great tolerances, the seal is fitted at the end of the piston that is adapted to be mounted close to a pressure chamber within the system. The seal is provided with radially-extending projections which cause the piston to spring back by a roll-back effect.

Abstract: Disc brake assembly (10) includes a phenolic piston (16) disposed within a bore (14) of a housing (11), the piston (16) movable relative to the housing (11) in order to engage brake shoe pads (18, 20) with the disc (22) of the brake assembly. An interior seal ring (42) and an exterior boot seal (60) are disposed between the bore (14) and piston (16) in order to prevent contaminants from entering into the bore and damaging the phenolic piston. Located between an annular groove (40) receiving the interior seal ring (42) and an exterior opening (50) receiving one end of the exterior boot seal (60), is a land (70). The land (70) is protected by a corrosion resistant barrier (80) which protects the land from oxidation and subsequent lock-up of the phenolic piston (16), and provides a low friction surface for engagement with the slidable piston.

Abstract: A spot-type disc brake, especially for automotive vehicles, comprises a brake carrier and a brake housing having two radial legs and an interconnecting bridge so as to straddle the rim of a brake disc. Brake pads disposed on either side of the brake disc, with the brake housing being disposed in axially displaceable manner on the brake carrier and actuable by an actuating device. To avoid a screw connection on the outer brake pad, for attaching a brake pad to the adjacent leg of the brake housing, at least one attachment element engages, in a locking manner, ports of the leg and of the brake pad. A spring is secured to the brake pad by way of which the brake pad is resiliently in abutment with bearing points provided on the brake housing.

Abstract: The hydraulic brake adjuster (10) intensifying and piston assembly (30) include an exterior pressure device (11) which is disposed separate from a piston (32). The exterior pressure device (11) includes a differential area piston (12) receiving actuation fluid pressure and an outlet (26) which communicates fluid pressure to the piston assembly (30). The piston assembly (30) includes a piston bushing (40) received within the piston (32) to define substantially therebetween a pair of longitudinal pressure chambers (50, 95), a recessed piston (60) received within the piston bushing (40) to define therebetween an axial pressure chamber (70), the axial pressure chamber (70) communicating with one (50) of the pair of longitudinal pressure chambers (50, 95), and the one longitudinal pressure chamber (50) receiving actuation fluid pressure. A piston valve (90) is located within an interior opening (97) in the piston (60), the interior opening (97) communicating with the axial pressure chamber (70).

Abstract: Pneumo-hydraulic converter for disc brake callipers, particularly for commercial vehicles, comprising a body intended for application directly to a brake calliper or in the immediate vicinity thereof and having a central axis cavity in which there is sealingly slidable a first piston to which is fixed a second piston sealingly slidable in a pneumatic chamber formed at one end of the body and connected at one end to a pressurized air supply and containing a biassing spring for the first and second pistons at its opposite end. The first piston is operatively associated with a hydraulic chamber formed at the other end of the body and defined by a hollow slider guided axially within the body and intended to operate the brake calliper, and the hydraulic chamber is connected to a hydraulic fluid reservoir.

Abstract: A floating caliper of a spot-type disc brake supported for displacement with respect to a carrier member which is fixed to a vehicle and includes two brake pads for pressurizing the brake disc from either side. A hydraulic piston and cylinder assembly in the floating caliper directly pressurizes one of the pads and indirectly pressurizes the other pad by way of the floating caliper, with a sliding guide being provided between the carrier member and the floating caliper wherein one of the pads is supported circumferentially exclusively on the floating caliper and the other pad is exclusively supported on the piston of the piston and cylinder assembly, another sliding guide being provided on the carrier member for engagement by the piston.

Abstract: A hydraulically controlled brake comprises a rotatable disc straddled by two opposite hydraulic cylinder bodies, fastened together by fixing means. In each body is slidably mounted a piston which defines in the body a hydraulic chamber, the pistons being adapted to urge a respective brake pad into frictional engagement with said disc when hydraulic pressure is generated in the chambers. The chambers are fed by a conduit, at least a portion of which crosses the interface which is between the assembled cylinder bodies at a location coincidental with the point where the fixing means cross that interface. Thus, there is no need for two separate conduits to feed the two chambers, which are instead fed by a single conduit.

Abstract: The invention provides a wheel assembly consisting of first and second spaced apart coaxial wheels. The wheel are mounted on a support structure such that they can rotate relative to one another. A first brake rotor is non-rotatably connected to the first wheel, and a second brake rotor is non-rotatably connected to the second wheel. A brake stator is operable on each rotor to oppose rotation of the two brake rotors simultaneously.

Abstract: A disc brake caliper is mounted with a rollpin or similar sleeve secured between the brake torque transmitting member and the brake torque receiving member. The rollpin sleeve is also positioned about the brake hose applying braking pressure to the caliper assembly so that when brake actuation occurs the caliper brake torque reaction compresses the rollpin, closing the brake hose passage completely when the maximum permissible braking torque is exerted. Thus the brake actuating pressure and the resulting braking effort are limited so that the wheel does not reach incipient wheel lock at maximum allowable braking effort on dry pavement.

Abstract: A spring member for use in a disc type friction coupling mechanism for urging the movable friction members associated with such devices toward their inoperative retracted positions, the spring member having a planar loop portion and at least one arm portion associated therewith, each of the arm portions being angularly displaced relative to the plane of the loop portion, the loop portion being removably attachable to the actuator assembly such that each spring arm portion respectively engages a friction member on the actuator assembly to urge the friction member engaged therewith toward its inoperative retracted position.

Abstract: A brake apparatus has an actuator mechanism for bringing a friction member into tight contact with a braking member so as to obtain a braking force, the actuator mechanism including: a moving piezoceramic member which can be elongated/contracted along a direction in which the friction member is urged; a holder disposed between opposing ends of the friction member and the moving piezoceramic member to couple the friction member and the moving piezoceramic member; and members for selectively restraining movement of the moving piezoceramic element in a direction parallel to the direction in which it is urged with respect to a fixing member.

Abstract: An actuating mechanism is disclosed as particularly useful for a braking assembly, and especially for a disc brake assembly. The mechanism is a device having elastic properties formed from a plurality of layers, or laminae of rigid (metal, hard plastic) and resilient (elastomer, rubber) members bonded together and to the inside of a casing or caliper housing sealing it therein. The casing together with the bonded and sealed actuator therein is threaded into the caliper housing of the brake assembly. Fluid pressure applied to the casing interior activates the mechanism and it yields by flexing axially. An attached brake shoe or pad is operated by the actuator, given an axial displacement and urged against the brake assembly drum or rotor in a braking action. The actuator mechanism returns the shoe or pad to a neutral, non rotor contacting position automatically when the pressure of the fluid in the casing is relieved.

Abstract: The invention relates to a hydraulic rim brake for bicycles with a triggering mechanism which is attached to the handlebar of the bicycle and is actuated by a hand lever, with two brake cylinder housings which are attached to the frame of the bicycle in oppositely located relationship to each other and enclose between them a wheel rim, the brake cylinder housings being connected by pressure lines to the triggering mechanism, with pistons displaceable in the brake cylinder housings, and with brake shoe supports arranged on these pistons for supporting brake shoes engaging the rim. In order to protect the piston from the effect of harmful bending moments, provision is made for the brake shoe supports to be in the form of flanges which are connected to the piston and are each displaceable parallel to the motion of the brake piston in a slide guide provided on the brake cylinder housing, and for the slide guide to simultaneously constitute abutments for absorption of the braking forces.

Abstract: The actuator comprises a piston (34) which has a stepped portion (36) formed with an annular groove (38) at its end projecting out of a cylinder (16). An annular protective sheet (50) is slipped on the stepped portion (36) and it comprises at its radially inner edge (52) inwardly projecting, resilient tongues (54) which are arrested in the annular groove (38). An annular elastic sleeve (46) is arranged behind the protective sheet (50), thereby being protected against heat, and provides sealing as against the piston (34), on the one hand, and the cylinder (16), on the other hand.

Abstract: A disc brake assembly is provided with a plate which cooperates with a pair of pistons to prevent rotation of one of the pistons relative to the caliper. The plate is further designed to act as a heat shield for a boot assembly associated with the piston.

Abstract: A fluid pressure actuated piston (78) is slidably carried in a fluid pressure actuated cylinder (50) which, in turn, is slidably carried in a fixed carrier or casing (21). Movement of the cylinder (50) is resisted by a breakable or displaceable coupler (90, 94, 184, 185) which engages the cylinder (50). Fluid pressure acting upon the cylinder (50) and piston (78) causes the coupler (90, 94, 184, 185) to break or be displaced and release the cylinder (50) for axial movement in the direction of movement of the pressure responsive piston (78).

Abstract: A disc brake has a hydraulic parking brake actuator. A parking brake piston is advanced upon actuation to close a parking brake valve, sealing hydraulic fluid in the service pressure actuating chamber. Further advancing movement of the parking brake piston generates hydraulic pressure in the actuating chamber and engages the brake. Increased pressure in the actuating chamber also increases the sealing force on the valve controlling the sealing of the pressure chamber. The parking brake mode may also be obtained while hydraulic service brake pressure exists in the actuating chamber by moving the parking brake piston sufficiently to close the parking brake valve, trapping pressurized hydraulic fluid in the actuating chamber and holding the brake in the actuated condition. This pressure may be further increased, if desirable, by further advancing movement of the parking brake piston to further increase the pressure.

Abstract: A boot assembly for preventing ingress of dirt into one end of a bore in a housing in which a piston works usually consists of a first portion sealing against the housing adjacent to the end of the bore, a second portion sealing against the piston and a flexible web connecting the two. To prevent the second portion lifting away from the piston, to which it is conventionally attached by being stretched round a groove at the end of the piston, the boot assembly is combined with a plate, having its outer peripheral edge sealingly connected to the second portion, and an inner face in abutment with the adjacent end of the piston.

Abstract: The open bore of a disc brake caliper assembly is protected by a resilient boot and retainer assembly (92). The piston (38) which forces the friction elements (26, 32) against the friction faces (14, 16) of the rotor (12) is provided with a circumferentially extending groove (118) which receives the bead (96) circumscribing one end of the boot (94). The bead (98) circumscribing the other end of the boot (94) is clamped against a land (122) of the piston 38 by a boot retainer (110). The boot retainer (110) is provided with a radially projecting portion (112) which is held against a circumferentially extending face (108) on the wall of the caliper housing (22) by the oil seal (116). Accordingly, the boot (94) may be removed and a new one installed when the brake is serviced without disassembly of the caliper assembly by withdrawing the piston (38) until the groove (118) is brought into registry with the projection (106), thereby permitting removal of the old boot and installation of a new one.

Abstract: In floating-caliper disc brakes, the friction in the caliper guides hinder movement of the caliper in the brake release direction, thus, increasing the drag of the brake when it is not operated. According to the present invention, the reaction portion of the caliper is provided with an applying piston of small axial length whose axial movement is limited to an amount equal to the required brake clearance. The applying piston is spring biased in the release direction, thus, producing the brake clearance without movement of the caliper.

Abstract: The spot-type floating-caliper disc brake includes at least one guide bolt secured to the brake support member and extending from the support member into an axial bore of the floating caliper adjacent the side of the brake cylinder. A roll-back sealing ring is provided at both ends of the axial bore, one disposed in an annular groove of the floating caliper and the other disposed in an annular groove of the guide bolt. As a result, a pressure chamber is formed around the guide bolt which communicates with the hydraulic brake circuit. With this arrangement, the brake shoe that is connected directly to the floating caliper will be reset to the nominal brake clearance after a braking operation.

Abstract: The outboard brake lining is attached directly to the housing rather than to a brake shoe. The inboard line is received in the housing bore and brake fluid acts against a cap for a piston made of lining material, eliminating the conventional piston and inboard shoe. The cylinder is attached by integrally formed screw threads to the cast caliper body.

Abstract: An inexpensive frictional coupling mechanism, useful in smaller brakes and clutches includes an air operated piston and cylinder assembly for single or double-acting use in either a dual disc, single disc or caliper type frictional brake or clutch arrangement.

Abstract: A disc brake having a pair of pistons composed of a Devitroceramics having a heat conductivity of about 1.times.10.sup.-3 cal/cm.sec..degree.C. to about 4.times.10.sup.-2 cal/cm.sec..degree.C., a bend strength of about 5 kg/mm.sup.2 to about 55 kg/mm.sup.2, a Vickers' hardness of about 400, and a density of smaller than about 4.0 g/cm.sup.3. A method of manufacturing the disc brake comprises incorporating into the disc brake a pair of pistons which are prepared by mixing the component materials of the Devitroceramics, melting them to a homogeneous molten state, molding the molten materials into a piston-shaped article, annealing the article for crystallization and heating the article.

Abstract: A self-adjusting rear disc brake assembly provided with a parking brake to mechanically actuate the disc brake, as well as having hydraulic service brake actuation, has a confined air space between the outer piston and the inner piston. The pressure compensator and seal embodying the invention operates to maintain the confined air space substantially at ambient air pressure while preventing contamination of the brake actuating mechanism by air borne contaminants normally encountered in the area of a vehicle rear brake mechanism.

Abstract: A light weight metal caliper housing has cored holes in the cast bore. A nylon bore insert lines the bore side wall. A molded flex piston has hydraulic fittings incorporated as a part of it and the fittings extend through the cored holes. The center portion of the piston is shaped to permit piston flexibility for axial expansion and contraction. The forward end of the piston is closed by a thermal protector, the outer surface of which is engaged by the back of the brake shoe. A low rate extension spring within the piston returns the piston to the fully non-applied position. The spring has one end attached to a plate which resists movement within the free piston but is moved when sufficient brake lining wear occurs so that the extension force applied through the spring during brake apply overcomes the resistance of the movable plate to such movement, causing the movable plate to assume an adjusted position.

Abstract: A hydraulically operated disk brake apparatus for a motor vehicle comprises a brake disk, a caliper-like brake housing disposed to straddle over the brake disk and having a pair of arms, and a pair of brake pad assemblies disposed in the brake housing in opposition to each other with the brake disk being interposed therebetween. The brake pad assemblies are movable toward and from the brake disk. A cylinder chamber is formed in one of the caliper arms and accommodates therein a first piston for pressing the adjacent brake pad assembly to the brake disk and a second piston positioned with a distance from the first piston. The second piston is operated by an externally provided actuator member to produce a hydraulic pressure in the cylinder chamber for moving the first piston and the associated brake pad assembly toward the brake disk. A reservoir for hydraulic fluid is formed in the brake housing to supply supplementary fluid into the cylinder chamber.

Abstract: A fluid pressure actuated piston of an aircraft multiple disc brake assembly is adapted to have an extended stroke by telescoping with a pressure actuated cylinder. The piston is slidably carried in a fluid pressure actuated cylinder which, in turn, is slidably carried in a fixed carrier. Initially, only the piston moves axially to extend its stroke with respect to the carrier. The cylinder's structure and axial position with respect to the carrier creates a fluid pressure responsive surface area initially sealed from the effects of the fluid pressure. Axial movement of the cylinder is initially resisted by either mechanical or differential pressure member until the stroke of the piston reaches a predetermined axial position to engage the cylinder. Continued extension of the piston's stroke urges the cylinder axially to break the fluid seal and expose the heretofore unaffected surface area of the cylinder to fluid pressure thereby extending the stroke of the cylinder a predetermined axial distance.

Abstract: A fluid pressure actuated piston of an aircraft multiple disc brake assembly is adapted to have an extended stroke by telescoping with a pressure actuated cylinder. The piston is slidably carried in a fluid pressure actuated cylinder which, in turn, is slidably carried in a fixed carrier. Initially, only the piston moves axially to extend its stroke with respect to the carrier. The cylinder's structure and axial position with respect to the carrier creates a fluid pressure responsive surface area initially sealed from the effects of the fluid pressure. Axial movement of the cylinder is initially resisted by either mechanical or differential pressure member until the stroke of the piston reaches a predetermined axial position to engage the cylinder. Continued extension of the piston's stroke urges the cylinder axially to break the fluid seal and expose the heretofore unaffected surface area of the cylinder to fluid pressure thereby extending the stroke of the cylinder a predetermined axial distance.

Abstract: A service brake actuating assembly is effective to bring friction material into contact with the opposite sides of a rotating disc by urging such elements in an axial direction toward a reaction wall. A compact parking and emergency brake actuating assembly extends through the wall and is alternately effective to also clampingly engage the disc by urging such elements in the opposite axial direction.

Abstract: A braking device for a bicycle comprising brake shoes positioned on opposite sides of a wheel of the bicycle for being brought into operative contact with the wheel to effect braking of the bicycle under the action of a movable brake handle and in opposition to a restoring spring. A hydraulically actuable pressure member is operatively coupled to each brake shoe to displace the same to its braking position and a hydraulic cylinder is operatively coupled to the brake handle for being actuated thereby. A hydraulic circuit connects the hydraulic cylinder and the hydraulically actuable pressure members for pressurizing the latter when the hydraulic cylinder is actuated by the brake handle.

Abstract: A plastic disc brake piston is disclosed with a novel fluted inner core design, giving a piston with superior structural strength, crack resistance, and improved heat dissipation when used in disc brake assemblies.

Abstract: A disc brake operating piston includes a hollow, cylindrical body which is open at one end thereof and is closed at its opposite end by an integral base member. The body is formed of a synthetic resin material and the base member is provided with an upstanding projection which is fixed relative to the base member and which extends to a position for engagement, in use, with the backing member of a disc brake friction pad. At least part of the projection is defined, over the whole length thereof, within an area bounded by a circle concentric with the body and having a radius up to one half of the radius of the bore in the body at the base member.

Abstract: A disc brake which includes a disc mounted on a rotating shaft and a fixed clamp which carries brake elements which may be moved to and from the disc by controlled pneumatic or hydraulic pressure agents. The brake elements are in contact with a pressure head which may be soldered, welded or glued to one end of a self-supporting spring pipe which is directly connected to the clamp at the opposite end of the pipe by way of a suitable flange. The spring pipe forms the final link between the pressure system and the brake elements.

Abstract: A piston-cylinder unit for use in a disc brake assembly includes a cylinder and a hydraulically actuated piston received in the cylinder for axial movement therein. The unit has a flexible seal member with its opposite ends attached in sealing engagement to respective axially opposed portions of the piston and cylinder for elastic expansion and contraction in the axial direction. The flexible seal member and the opposing portions of the piston and cylinder form a chamber for receiving fluid pressure for actuation of the piston.

Abstract: A disk brake assembly including a stamped sheet metal integral body having at least one substantially flat side wall with top and end portions projecting from the top and end edges, respectively, of the side wall. An actuator opening is formed in the side wall, and a flange projects from the periphery of the opening to define an integral sleeve. A disk brake actuator module is received in the opening and sleeve, the module including a cylindrical housing having a closed end and an open end with an actuator mounted therein and axially extendable and retractable with respect to the housing in response to fluid pressure changes in the housing. The module housing is received in the sleeve with a friction fit and is formed with a retaining flange that engages the side wall of the integral body to prevent axial movement of the housing in one direction relative to the side wall.

Abstract: There is provided an improved disc brake caliper assembly characterized by a caliper body having first and second legs and a member joining them, and having a cylindrical bore extending through one of the legs and dimensioned to receive a cup-shape piston having a head portion and a piston skirt. A flanged second piston relatively movable in the cup-shaped piston is provided with an intermediate shoulder dimensioned to fit into said cylindrical bore and form therewith an annular chamber in which the skirt of the cup-shaped piston moves. A first fluid chamber is formed between the head of the second piston member and the inside closed end of the cup-shaped piston. A second isolated annular chamber is formed between the open end of the piston skirt and the shoulder. The flanged portion of the second piston member is secured by suitable fastening members to a flange receiving surface on the first leg. Fabrication of such a device is simplified, easier to machine and to assemble.

Abstract: A rigid and deformable hydraulic seal for a force-applying mechanism, the seal being interposed between a piston and a housing cavity. This seal is generally cup-shaped and has an annular outer end portion that is rigidly retained in a peripheral groove of the housing cavity. Adjacent to this end portion is a half torus or single convolution hoop portion open toward the cavity, with the seal further including a generally cylindrical side surface and a circular bottom portion, with this seal, together with the cavity, defining a fluid-tight variable volume chamber. Fluid pressure supplied to this chamber causes plastic deformation of the seal and permits relative motion to occur between the piston and housing.

Abstract: A cylinder and piston subassembly including an improved fluid seal comprising a relatively loosely fitting piston within a cylinder structure and having a resilient diaphragm adhesively attached to a face of a piston and/or the cylinder structure.

Abstract: A disc brake assembly comprises a housing affixed to a non-rotatable member and having a through-hole therein. A cylinder is slidably fitted in the through-hole in the housing and has a pressure oil inlet, and a piston therein in sliding relation therewith. A disc is rotatable together with a rotating member, and a yoke is affixed to the cylinder and is movable with the cylinder. A member movably couples the yoke to the housing. A first friction pad is supported by the yoke and is adapted to be urged against or detached from one side of the disc, and a second friction pad is mounted on one end of the piston and is adapted to be urged against or detached from the other side of the disc.