DISC BRAKE APPARATUS WITH PARKING MECHANISM

• US 20120292137A1
• Filed: 01/26/2011
• Published: 11/22/2012
• Est. Priority Date: 01/26/2010
• Status: Active Grant

• Current Assignee: Akebono Brake Industry Company Limited (Akebono Brake Corporation)
• Original Assignee: Akebono Brake Industry Company Limited (Akebono Brake Corporation)
• Inventors: Yoshikawa, Kazuhiro, Yamadera, Shinichi
• Granted Patent: US 8,936,137 B2
• Time in Patent Office: Days
• US Class Current: 188/71.7
• CPC Class Codes: F16D 2121/02 Fluid pressure
• CPC Class Codes: F16D 2121/14 Mechanical
• CPC Class Codes: F16D 2123/00 Multiple operation forces
• CPC Class Codes: F16D 2125/28 Cams; Levers with cams
• CPC Class Codes: F16D 2125/36 Helical cams, Ball-rotating ramps
• CPC Class Codes: F16D 2127/06 Locking mechanisms, e.g. acting on actuators, on release mechanisms or on force transmission mechanisms
• CPC Class Codes: F16D 2250/0084 Assembly or disassembly
• CPC Class Codes: F16D 65/18 adapted for drawing members together , e.g. for disc brakes
• CPC Class Codes: F16D 65/567 for mounting on a disc brake

Abstract

Some of the components of a parking brake mechanism are incorporated between an inner side case and an outer side case, the two case and are combined by engaging lock holes and lock claws, and an inner side auxiliary assembly is formed. In this state, the diameter of circumscribed circle of the lock claws is configured to be smaller. Then, when the inner side auxiliary assembly is incorporated in the cylindrical space, the two lock claws are engaged with a lock concave which is formed on the inner peripheral surface of the cylindrical space by making the two lock claws protrude greatly from the outer peripheral surface of the inner side case.

Claims

1. A disc brake apparatus with a parking mechanism, comprising:

a rotor which is rotated with a vehicle wheel;

a support member which is adjacent to the rotor and is supported by and fixed to a vehicle body;

an inner pad and an outer pad which hold the rotor from both sides in the axial direction, and are supported by the support member to be displaceable in the axial direction;

a caliper which is provided with a caliper claw at an outer side end to push an outer side surface of the outer pad, and a cylindrical space at an inner side half part which opens to the inner pad, respectively, and is supported by the support member to be displaceable in the axial direction;

a piston which is embedded in a part of the cylindrical space that is close to the opening, and is displaceable in the axial direction; and

a parking mechanism which is provided between a back end surface of the cylindrical space and the piston,

wherein the parking mechanism expands an axial dimension with a rotation of a component that is rotated with a swing displacement of a parking lever which is provided outside the cylindrical space, and pushes the piston toward the inner pad,

components among the components of the parking mechanism except components that are installed to the piston are installed between an anti-rotor side case which is embedded and supported in the back end of the cylindrical space and a rotor side case which is placed at a rotor side of the anti-rotor side case,

a plurality of lock claws which are bended outwards in a radial direction of the rotor side case are formed at an anti-rotor side end of the rotor side case of the two cases,

lock parts which have end edges that face to the anti-rotor side are formed at a part of the anti-rotor side case,

in a state before the anti-rotor side case and the rotor side case are installed at predetermined positions of the cylindrical space, the two cases are prevented from being separated by means of an engagement of the lock claws and the lock parts, and

in a state where the anti-rotor side case of the two cases is embedded at a predetermined position of the back end of the cylindrical space and the rotor side case is installed at a predetermined position of the cylindrical space, the two cases are prevented from being uninstalled from the cylindrical space by engaging the lock claws with a lock concave which is formed on an inner peripheral surface of the cylindrical space.

2. The disc brake apparatus with the parking mechanism according to claim 1, wherein

the anti-rotor side case is embedded and supported at the back end of the cylindrical space so that rotation is prevent, and

the components that are installed between the anti-rotor side case and the rotor side case include:

an circular shaped anti-rotor side cam member which is provided with a plurality of anti-rotor side ramp parts whose depth in the axial direction gradually changes in the circumferential direction at the rotor side surface, and a through hole in the central part, and is embedded and supported at the back end of the anti-rotor side case so that a rotation relative to the anti-rotor side case is prevented;

a rotor side cam member which is provided with an outwards flange-like ramp plate part at the rotor side end of a shaft which is inserted into the through hole, and a plurality of rotor side ramp parts at the parts corresponding to the anti-rotor side ramp parts at the anti-rotor side surface of the ramp plate part whose depth in the axial direction gradually changes reversely to the anti-rotor side ramp parts in the circumferential direction;

rolling elements which are provided between the anti-rotor side ramp parts and the rotor side ramp parts to be freely rollable;

a cylindrical adjusting nut which is provided with a multi-thread adjusting female screw in the center part, and an outwards flange-like collar at the part of the outer peripheral surface that is close to the anti-rotor so that the rotation is prevented by means of the engagement of some parts of the collar with the anti-rotor side case;

a thrust bearing which are held between the rotor surface of the rotor side cam member and the anti-rotor side surface of the collar; and

a compression spring which is compressed elastically in the axial direction and held between the rotor side surface of the collar and the rotor side case.

3. The disc brake apparatus with the parking mechanism according to claim 1, wherein

the lock parts are lock holes which are formed at the rotor side end of the anti-rotor side case.

4. The disc brake apparatus with the parking mechanism according to claim 3, wherein

after the anti-rotor side case is embedded at the predetermined position of the back end of the cylindrical space, the lock claws are inserted into the lock holes from inside to outside in the radial direction either before or after the rotor side case is installed at the predetermined position of the cylindrical space,

before the installation, the separation of the two cases is prevented by engaging parts of the lock claws with the rotor side end edges of the lock holes, and

after the installation, the two cases are prevented from being uninstalled from the cylindrical space by engaging the protruded parts from the outer peripheral surface of the anti-rotor side case at the front ends of the lock claws with the lock concave.

5. The disc brake apparatus with the parking mechanism according to claim 3, wherein

the lock claws are formed at a plurality of places in the circumferential direction of the rotor side case at the anti-rotor side end of the rotor side case,

the lock holes are formed at the rotor side end of the anti-rotor side case,

in a state where the compression spring assembled between the anti-rotor side case and the rotor side case is compressed by a predetermined amount, the front ends of the lock claws and the rotor side edges of the lock holes are engaged so that the anti-rotor side case and the rotor side case are not separated, and

in a state where the compression spring is compressed over the predetermined amount, the front ends of the lock claws are protruded from the outer peripheral surface of the anti-rotor side case for an amount so that the front ends of the lock claws engage with the lock concave which is formed on the inner peripheral surface of the cylindrical space.

6. The disc brake apparatus with the parking mechanism according to claim 5, wherein

the lock claws are formed by bending the front ends of the resilient arms outwards in the radial direction of the anti-rotor side case,

steps are formed at the parts in the middle of the resilient arms that are close to the front ends by bending the front ends outwards so that the front ends are outside the base ends in the radial direction of the anti-rotor side case,

in a state where the parts of the resilient arms which are closer to the front end side than the steps contact the inner peripheral surface of the anti-rotor side case, the front ends of the lock claws and the lock holes are engaged so that the anti-rotor side case and the rotor side case are not separated, and

in a state where the parts of the resilient arms which are closer to the base end side than the steps contact the inner peripheral surface of the anti-rotor side case, the parts protruded from the outer peripheral surface of the anti-rotor side case at the front ends of the lock claws are engaged with the lock concave which is formed on the inner peripheral surface of the cylindrical space.

7. The disc brake apparatus with the parking mechanism according to claim 6, wherein

pressing plates are formed at the anti-rotor side ends of the lock holes by being bended inwards in the radial direction of the anti-rotor side case and extending towards the rotor side case, and

when the steps of the resilient arms enter into the lock holes, the lock claws are prevented from being displaced in the direction of uninstalling from the lock concave by making the front ends of the resilient arms enter the outside of the pressing plates in the radial direction.

8. The disc brake apparatus with the parking mechanism according to claim 5, wherein

the lock claws are formed by bending the front ends of the resilient arms outwards in the radial direction of the rotor side case,

the middle parts of the lock claws are provided with wide parts which are wider than the front ends,

the lock holes are provided with narrow parts at the rotor side parts which allow the front ends of the lock claws pass but do not allow the wide parts of the lock claws pass, and wide parts at the anti-rotor side parts which allow the wide parts of the lock claws pass, respectively,

in a state where the wide parts are engaged with the two side edges of the narrow parts, the front ends of the lock claws and the lock holes are engaged so that the anti-rotor side case and the rotor side case will not be separated, and

in a state where the wide parts of the lock claws pass the wide parts of the lock holes, the parts protruded from the outer peripheral surface of the rotor side case at the front ends of the lock claws are engaged with the lock concave which is formed on the inner peripheral surface of the cylindrical space.

9. The disc brake apparatus with the parking mechanism according to claim 3, wherein

the lock claws are formed by bending the anti-rotor side half parts of wide parts, which are provided at the front ends of the resilient arms that extend from a plurality of positions of the outer peripheral edge of the rotor side case in the circumferential direction of the rotor side case to the anti-rotor side and whose width in the circumferential direction of the rotor side case is larger than the width of the resilient arms in the same direction, outwards in the radial direction of the rotor side case, communication parts whose width in the circumferential direction of the anti-rotor side case is larger than the width of the resilient arms are provided between the central part of the lock holes in the circumferential direction of the anti-rotor side case and the rotor side end edge of the anti-rotor side case,

in a state after the anti-rotor side case is embedded at the predetermined position of the back end of the cylindrical space and before the rotor side case is installed at the predetermined position of the cylindrical space, the lock claws are inserted through the lock holes from inside to outside in the radial direction of the anti-rotor side case, and the two cases are prevented from being separated by means of the engagement of the lock claws with the two end parts in the circumferential direction of the lock holes, and

after the installation, in a state where the resilient arms pass the communication parts and are displaced outwards in the radial direction of the anti-rotor side case beyond the anti-rotor side case, the two cases are prevented from being uninstalled from the cylindrical space by means of the engagement of the front ends of the lock claws with the lock concave, and the lock claws are prevented from being uninstalled from the lock concave by means of the movement of the wide parts towards the outside of the communication parts in the radial direction of the anti-rotor side case.

10. The disc brake apparatus with the parking mechanism according to claim 1, wherein

the lock parts are the anti-rotor side end edge of the peripheral wall which forms the anti-rotor side case.

11. The disc brake apparatus with the parking mechanism according to claim 10, wherein

the peripheral wall has an incomplete cylindrical shape which has slits at a plurality of positions in the circumferential direction that communicate in the axial direction from the rotor side end edge to the anti-rotor side end edge,

parts of the peripheral wall are divided in the circumferential direction by the slits and mutually connected by a bottom plate which is provided at the anti-rotor side end of the anti-rotor side case, and

the bottom plate are not provided at parts of the anti-rotor end edge of the peripheral wall that align with the slits in the circumferential direction or parts of the anti-rotor end edge of the peripheral wall beside the slits.

12. The disc brake apparatus with the parking mechanism according to claim 11, wherein

the lock claws extend to the anti-rotor side from a plurality of positions of the outer peripheral edge of the rotor side case in the circumferential direction of the rotor side case that align with the slits, and are formed by bending the anti-rotor side half parts of wide parts, which are provided at the front ends of the resilient arms whose width in the circumferential direction is smaller than the width of the slits in the same direction, and whose width in the same direction is larger than the width of the slits in the same direction, outwards in the radial direction of the rotor side case,

in a state where after the anti-rotor side case is embedded at the predetermined position of the back end of the cylindrical space and before the rotor side case is installed at the predetermined position of the cylindrical space, the two cases are prevented from being separated by means of the engagement of the lock claws with the parts of anti-rotor side back end edge of the peripheral wall beside the slits in the circumferential direction, and

after the installation, the resilient arms are displaced outwards in the radial direction of the anti-rotor side case in the slits so that the two cases are prevented from being uninstalled from the cylindrical space by engaging the front ends of the lock claws with the lock concave.

13. The disc brake apparatus with the parking mechanism according to claim 12, wherein

continuing parts are provided between the wide parts and the resilient arms by bending inwards in the radial direction of the rotor side case from the front end edges of the resilient arms, and

in a state where base plates which are the rotor side half parts of the wide parts contact the parts of the inner peripheral surface of the anti-rotor side end of the peripheral wall beside the slits, the resilient arms are not protruded inwards in the radial direction from the inner peripheral surface of the peripheral wall.

14. The disc brake apparatus with the parking mechanism according to claim 13, wherein

in a state where the two cases are prevented from uninstall from the cylindrical space by engaging the front ends of the lock claws with the lock concave, some of the components that form the parking mechanism are made to enter the inside of the base plates of the wide parts in the radial direction of the rotor side case so that the lock claws are prevented from being displaced inwards in the radial direction of the rotor side case.