Sliding caliper disc brakes

Abstract

In a disc brake such as a sliding caliper disc brake, the caliper is mounted for movement with respect to a torque plate by pin assemblies extending into aligned openings in the caliper and torque plate. The pin assemblies are of multi-part construction, parts of the pin assemblies which provide for movement between the caliper and torque plate being able to remain undisturbed when the caliper is removed from the torque plate. Another feature is that the openings in the caliper or the torque plate are oversize, so that the pin assemblies are received as a free fit, and the pin assemblies are clamped in the oversize openings by interengagement of screw threaded portions. Sliding surfaces are provided either directly by the shanks of pins or by separate bushes which may be resilient. The construction is such that the pin assemblies are relieved of clamping forces and drag forces when the brake is actuated.

We claim: 
     
       1. A sliding caliper disc brake comprising a rotatable disc, a torque plate member for fixing to a vehicle frame or the like, a caliper member straddling a minor portion of the periphery of the disc for moving friction pad means disposed on opposite sides of the disc into braking engagement with the disc, portions of the torque plate member being arranged to receive directly drag forces experienced by each of the pad means, motor means in the caliper member for directly urging one pad means onto one side of the disc to cause the caliper member to slide relative to the torque plate member to apply by reaction the opposite pad means to the other side of the disc, and a sliding connection between the caliper member and the torque plate member comprising a first component slidably received in an opening in one of the members, a second component passing through an oversized opening in the other of said members and screw threadedly engaging said first component to releasably clamp the same against the other of said members, said oversized opening providing sufficient clearance for relative transverse movement between said second component and the other of said members. 
     
     
       2. The brake of claim 1 wherein said one of said members is the torque plate member and the other of said members is the caliper member. 
     
     
       3. The brake of claim 1 including resilient means between the sliding surfaces of said first component and said one of said members. 
     
     
       4. The brake of claim 1 having a pair of said sliding connections and including resilient means between the sliding surfaces of one of said pair. 
     
     
       5. The brake of claim 1 including means for holding one of said components against rotation whilst the other component is rotated during formation and release of said sliding connection. 
     
     
       6. The brake of claim 1 wherein said second component has a formation by which said second component may be rotated and said first component has a formation by which said first component may be held against rotation and wherein said formations are both on the same side of the disc. 
     
     
       7. A sliding caliper disc brake comprising a rotatable disc, a torque plate member adapted for fixing to a vehicle frame or the like, a caliper member slidable relative to said torque plate member for moving friction pads disposed on opposite sides of said brake disc into braking engagement with said disc, portions of the torque plate member being arranged to receive directly drag forces experienced by each pad means, at least one removable pin means constructed in two parts, one of said parts having a sliding surface in a complementary opening in one of said members, the other of said parts passing with a clearance fit through an oversize opening in the other of said members and being threadedly engaged with the first part of said pin means, said clearance fit allowing transverse movement of said other part in said opening, said first and second pin parts having opposed abutment surfaces engaging said other member at opposite ends of said oversized opening and being constructed and arranged that when said pin parts are lockingly screwed together the abutment surfaces clamp between them the opposite sides of said other member with sufficient force to prevent said transverse movement of said pin part in said oversized opening and thereby rigidly fixing said pin part in said oversized opening. 
     
     
       8. A sliding caliper disc brake according to claim 7 wherein said one of said members is said torque plate member and said other of said members is said caliper member. 
     
     
       9. A sliding caliper disc brake according to claim 7 wherein said one of said members is said caliper member and said other of said members is said torque plate member. 
     
     
       10. A sliding caliper disc brake according to claim 7 including resilient means between the sliding surfaces of said pin means and said one of said members. 
     
     
       11. A sliding caliper disc brake according to claim 7 having a pair of said removable pin means and including resilient means between the sliding surfaces of one of said pair. 
     
     
       12. A sliding caliper disc brake according to claim 7 including means for holding one of said parts against rotation whilst the other of said parts is rotated during formation and release of the sliding connection between said members. 
     
     
       13. A sliding caliper disc brake according to claim 7 wherein said second part has a formation by which said second part may be rotated and said first part has a formation by which said first part may be held against rotation and wherein said formations are both on the same side of the disc. 
     
     
       14. A sliding caliper disc brake according to claim 7 wherein said complementary opening is closed at one end and wherein sealing means seal the other end. 
     
     
       15. A sliding caliper disc brake comprising a rotatable disc, a torque plate member for fixing to a vehicle frame or the like, a caliper member straddling a minor portion of the periphery of the disc for moving friction pad means disposed on opposite sides of the disc into braking engagement with the disc, portions of the torque plate member being arranged to receive directly drag forces experienced by each of the pad means, motor means in the caliper member for directly urging one pad means onto one side of the disc to cause the caliper member to slide relative to the torque plate member to apply by reaction the opposite pad means to the other side of the disc, and a sliding connection between the caliper member and the torque plate member comprising a first component slidably received in an opening in one of the members, and a second component passing through an opening in the other of said members and being laterally adjustable therein into alignment with said first component, said first and second components having complementary screw-threaded portions by which said first and second components are locked together to clamp said first component to said other of said members. 
     
     
       16. A sliding caliper disc brake comprising a rotatable disc, a torque plate member for fixing to a vehicle frame or the like, a caliper member straddling a minor portion of the periphery of the disc for moving friction pad means disposed on opposite sides of the disc into braking engagement with the disc, portions of the torque plate member being arranged to receive directly drag forces experienced by each of the pad means, motor means in the caliper member for directly urging one pad means onto one side of the disc to cause the caliper member to slide relative to the torque plate member to apply by reaction the opposite pad means to the other side of the disc, and a sliding connection between the caliper member and the torque plate member comprising a first component slidably received in an opening in one of the members, and a second component having a screw-threaded portion and passing through an opening in the other of said members and being laterally adjustable therein into alignment with a complementary screw-threaded opening in said first component, said first and second components being locked together by screw-threaded engagement to clamp said first component to said other of said members. .Iadd. 
     
     
       17.  A vehicle brake comprising a carrier member for fixing to a vehicle frame, a caliper member for straddling a rotatable disc, and an actuator for urging a first friction pad onto one surface of the disc to cause the caliper member to move relative to the carrier member and apply a second friction pad to an opposite surface of the disc, the brake having between the carrier member and the caliper member a sliding connection comprising a pair of pins each of which is slidable in and circumferentially surrounded by a respective oversized opening in one of the members and secured to the other of said members, both of said pins being relieved of transmitting braking forces from said friction pads to said carrier member by means which transmit such braking forces directly or indirectly from both of said pads to the carrier member, the oversized openings being sufficiently greater than the corresponding dimension of said pins as to permit lateral movement of the latter during actuation of the brake, said pins sliding in said openings during each actuation of the brake said brake including resilient biasing means causing said pins to adopt eccentric positions in their respective oversized openings with said pins in sliding contact with a portion of the walls of said oversized openings, said resilient biasing means acting in such a direction as to maintain, at least when the brake is in a released condition, freedom of lateral movement of each pin in its respective oversized opening in a direction generally towards the other oversized opening, whereby to permit the sliding connection to accommodate deformation of the carrier member during brake application. .Iaddend. .Iadd.18. A brake according to claim 17 in which said pins are secured to said caliper member and in which said resilient biasing means are operable to urge said caliper member generally radially outwardly of the disc. .Iaddend. .Iadd.19. A brake according to claim 18 in which said resilient biasing means is a leaf spring engaging said caliper member. .Iaddend. .Iadd.20. A brake according to claim 19 in which said leaf spring is adapted to engage the friction pads so as to urge said friction pads radially inwardly against abutment surfaces on said carrier member. .Iaddend. .Iadd.21. A brake according to claim 17 in which at least one of said pins carries a resilient sheath surrounding said pin over a major portion of its axial distance; which provides the sliding surface of the pin. .Iaddend. .Iadd.22. A vehicle brake according to claim 17 wherein said oversized opening comprises a blind bore in said one of said members. .Iaddend. .Iadd.23. A vehicle brake comprising a carrier member for fixing to a vehicle frame, a caliper member for straddling a rotatable disc, and an actuator for urging a first friction pad onto one surface of the disc to cause the caliper to move relative to the carrier member and apply a second friction pad to an opposite surface of the disc, the brake having between the carrier member and the caliper member a sliding connection comprising a pair of pins each of which is slidable in and circumferentially surrounded by a respective opening in one of the members and secured to the other of said members, both of said pins being relieved of transmitting braking forces from said friction pads to said carrier member by means which transmit such braking forces directly or indirectly from both of said pads to the carrier member, at least one of said openings being sufficiently oversized to permit radial movement of its respective pin during actuation of the brake, and at least one of said pins being secured to said other member in such a manner as to be laterally adjustable with respect to said other member whereby to permit accurate lateral positioning in the or each oversized opening of the pin or pins. .Iaddend. .Iadd.24. A brake according to claim 23 in which the or each laterally adjustable pin is secured to said other member by releasable clamping means comprising a clamping screw in screw-threaded engagement with the pin and passing through an opening in said other member so as to clamp the pin against said other member, said opening in said other member being sufficiently oversized as to permit lateral movement of said clamping screw in said opening prior to rigid clamping of the pin against said other member by said clamping screw. .Iaddend. .Iadd.25. A vehicle brake comprising a carrier member for fixing to a vehicle frame, a caliper member for straddling a rotatable disc, and an actuator for urging a first friction pad onto a one surface of the disc to cause the caliper to move relative to the carrier member and apply a second friction pad to an opposite surface of the disc, the brake having between the carrier member and the caliper member a sliding connection comprising a pair of pins each of which is slidable in and circumferentially surrounded by a respective oversized opening in one of the members and secured to the other of said members, at least one of said pins being secured to said other member in such a manner as to be laterally adjustable with respect to said other member, both of said pins being relieved of transmitting braking forces from said friction pads to said carrier member by means which transmit such braking forces directly or indirectly from both of said pads to the carrier member, the oversized openings being sufficiently greater than the corresponding dimension of said pins as to permit radial movement of the latter during actuation of the brake, said braking including resilient biasing means causing said pins to adopt eccentric positions in their respective oversized openings with said pins in sliding contact with a portion of the walls of said oversized openings, said resilient biasing means acting in such a direction as to maintain, at least when the brake is in a released condition, freedom of lateral movement of each pin in its respective oversized opening in a direction generally towards the other oversized opening, whereby to permit the sliding connection to accommodate deformation of the carrier member during brake application. .Iaddend. .Iadd.26. A brake according to claim 25 in which said pins are secured to said caliper member and in which said resilient biasing means are operable to urge said caliper member generally radially outwardly of the disc. .Iaddend. .Iadd.27. A brake according to claim 26 in which said resilient biasing means is a leaf spring engaging said caliper member. .Iaddend. .Iadd.28. A brake according to claim 27 in which said leaf spring is adapted to engage the friction pads so as to urge said friction pads radially inwardly against abutment surfaces on said carrier member. .Iaddend. .Iadd.29. A brake according to claim 25 in which at least one of said pins carries a resilient sheath which provides the sliding surface of the pin. .Iaddend. .Iadd.30. A brake according to claim 25 in which the or each laterally adjustable pin is secured to said other member by releasable clamping means. .Iaddend. .Iadd.31. A brake according to claim 30 in which said clamping means comprises a clamping screw in screw-threaded engagement with the pin and passing through an opening in said other member so as to clamp the pin against said other member, said opening in said other member being sufficiently oversized as to permit lateral movement of said clamping screw in said opening prior to rigid clamping of the pin against said other member by said clamping screw. .Iaddend. .Iadd.32. A vehicle brake comprising a carrier member for fixing to a vehicle frame, a caliper member for straddling a rotatable disc, and an actuator for urging a first friction pad onto one surface of the disc to cause the caliper to move relative to the carrier member and apply a second friction pad to an opposite surface of the disc, the brake having between the carrier member and the caliper member a sliding connection comprising a pair of pins each of which is slidable in and circumferentially surrounded by a respective opening in one of the members and secured to the other of said members, both of said pins being relieved of transmitting braking forces from said friction pads to said carrier member by means which transmit such braking forces directly or indirectly from both of said pads to the carrier member, at least one of said openings being sufficiently oversized to permit radial movement of its respective pin during actuation of the brake, said pins sliding in said openings during each actuation of the brake and the pin extending into the oversized opening or at least one of the pins extending into the two oversized openings carrying a resilient sheath which provides the sliding surface of the pin, and resilient biasing means acting to cause said pin and sheath to adopt eccentric positions in their respective oversized openings, at least when the brake is in a released condition, to maintain freedom of lateral movement of each pin in its respective oversized opening in a direction generally towards the other oversized opening, whereby to permit the sliding connection to accommadate deformation of the 
     
     
        carrier member during brake application. .Iaddend. .Iadd.33.  A vehicle brake comprising a carrier member for fixing to a vehicle frame, a caliper member for straddling a rotatable disc, and an actuator for urging a first friction pad onto one surface of the disc to cause the caliper to move relative to the carrier member and apply a second friction pad to an opposite surface of the disc, the brake having between the carrier member and the caliper member a sliding connection comprising a pair of pins each of which is slidable in and circumferentially surrounded by a respective opening in one of the members and secured to the other of said members, both of said pins being relieved of transmitting braking forces from said friction pads to said carrier member by means which transmit such braking forces directly or indirectly from both of said pads to the carrier member, at least one of said openings being sufficiently oversized to permit relative radial movement between said opening and its respective pin during actuation of the brake, said pins sliding in said openings during each actuation of the brake and a resilient sheath surrounding that pin which extends into said at least one oversized opening, said sheath providing a sliding surface for said pin within said oversized opening, and resilient biasing means acting to cause said pin and sheath to adopt eccentric positions in their respective oversized openings, at least when the brake is in a released condition, to maintain freedom of lateral movement of each pin in its respective oversized opening in a direction generally towards the other oversized opening, whereby to permit the sliding connection to accommadate deformation of the carrier member during brake application. .Iaddend.