JPH10292832A - Disk brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk brake in which the braking effective radius of a disk rotor is large, and by which effective braking can be obtained. SOLUTION: The disk part 24 of a wheel 22 is fixed to an axle hub 16, and a disk rotor 32 that is extended toward the inside in the radial direction is provided to the inner circumfential surface of the rim part 26. A caliper 42 is fitted to a bearing box 10 so as to be movable and also in such a state that it bestrides the disk rotor 32 and friction pads 38, 40 from the inner circumferential side. The caliper 42 includes a reaction member 56 that is turnable in the state that the fixing by means of a cylinder member 54 and screws 84 has been released. The braking effective radius of the disk rotor 32 can be increased as much as the caliper 42 is provided to the inner circumferential side so that a greater braking torque can be obtained. The disk rotor 32 is removed by releaving both the fixing of the wheel 22 to the axle hub 16 and the fixing of the reaction member 56 to the cylinder member 54, by moving the wheel 22 to the outside of the wheel, and by turning the reaction member 56. The disk rotor and the wheel may be separately made and then fixed together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc brake, and more particularly to an improvement in effectiveness.

[0002]

2. Description of the Related Art Generally, a disc brake is constituted by (a) an annular disk rotor having friction surfaces on both sides and rotating with a wheel, and (b) slidable contact with the friction surfaces on both sides. (C) a pair of provided friction pads;
A caliper is provided so as to straddle the pair of friction pads and the disk rotor and presses the pair of friction pads against the corresponding friction surfaces. The disc brake described in Japanese Patent Publication No. 7-507378 is an example thereof. In this disc brake, a wheel is rotatably mounted on a knuckle spindle via a bearing, and a disc rotor is fixed to the wheel. The wheel has a double cylindrical portion with different diameters around its rotation axis, the inner cylindrical portion is fitted to the outer race of the bearing, and the outer cylindrical portion is rotated by an annular disk rotor. It is mounted so that it cannot move and cannot move in the axial direction. The relative rotation between the disk rotor and the wheel is achieved by fitting the plurality of V-shaped cross-section recesses formed on the outer peripheral portion of the cylindrical portion with the plurality of V-shaped cross-section protrusions formed on the inner peripheral surface of the disk rotor. And the pair of locking rings prevents the disk rotor from moving in the axial direction. In this disc brake, the braking torque acting on the disc rotor is transmitted to the wheel by fitting the recess and the projection. Therefore, as in the case where the disk rotor and the wheel are fixed to the axle hub by a common bolt, and the braking torque is transmitted to the wheel via the bolt,
There is no need to increase the diameter of the bolt for fixing the wheel to the axle hub. However, in this disc brake, it is difficult to increase the effective braking radius. The size of the space for disposing the disk rotor and the like in the wheel is limited, and the caliper and the mounting bracket that supports the caliper are disposed between the outer periphery of the disk rotor and the wheel. The diameter of the disk rotor is relatively limited.

[0003]

SUMMARY OF THE INVENTION According to the present invention, there is provided a disk in which the effective braking radius can be increased in a space within a wheel having a limited area and a large braking torque can be obtained. It is an object to provide a brake. This problem is solved by the following disc brakes. Each mode is given a section number for each mode, and described in the same format as the claims to which reference is made to the numbers of other sections as necessary. This is to clarify the possibility of combining the features of each item. (1) In the disk brake including the disk rotor of (a), the pair of friction pads of (b), and the caliper of (c), the disk rotor is fixed to the wheel on the outer peripheral side and extends radially inward. A disc brake in which the caliper straddles the disc rotor and the pair of friction pads from the inner peripheral side. Here, "fixing" means that the disk rotor and the wheel are separate members, and they are fixed by fastening means such as bolts and rivets, as well as the disk rotor and the wheel as described in the embodiment of the invention. To be integrally formed. In the disc brake according to the present invention, since the caliper is provided so as to straddle the disc rotor and the friction pad from the inner peripheral side, the disc rotor is disposed correspondingly to the outer peripheral portion of the space in the wheel. As a result, the effective braking radius increases, and a large braking torque can be obtained. Also,
The heat generated by friction between the disk rotor and the friction pad is transmitted to the wheel during braking, but the wheel has a large heat capacity compared to the disk rotor, and has a large cooling effect because it is in contact with the atmosphere on a wide surface. Overheating of the disk rotor can be avoided well. (2) The wheel is fixed to a shaft member, and the caliper is attached to an outer peripheral portion of a cylindrical member fitted to the outside of the shaft member and rotatably holding the shaft member.
Disc brake described in (1). The caliper may be attached to the cylindrical member so as to be relatively movable in the axial direction, or may be attached to the cylindrical member so as to be relatively immovable in the axial direction. If the rotating member to which the wheel is fixed is a shaft member, the member that rotatably supports the rotating member is a cylindrical member, and if the rotating member is fitted into the cylindrical member, the rotating member can be rotatably supported. The mounting of the caliper becomes easy. However, this is not indispensable, and the rotating member to which the wheel is fixed is a cylindrical member, the member that rotatably supports the rotating member is the shaft member, and the cylindrical member is rotatably fitted to the outside of the shaft member. You may. In this case, for example, the caliper may be attached to a support portion extending from the non-rotating member such as a steering knuckle toward the disk rotor so as to be relatively movable in the axial direction or to be relatively immovable. (3) Of the two portions of the caliper, located on both sides of the pair of friction pads and the disk rotor, the outer portions located on the outer side in the vehicle width direction correspond to the corresponding friction pads and the disk rotor in the vehicle width direction. The disc brake according to (1) or (2), including a detachment permitting means for permitting the detachment to the outside. The detachment permitting means enables the outer part to move to an operation position facing the disk rotor and to a retracted position not facing the disk rotor even with the detachment permitting means for permitting the outer part of the caliper to be detached from the other part of the caliper. Evacuation permitting means may be used. The removal of the friction pad is performed, for example, when the friction pad is replaced due to wear of the friction material. Further, since the wheel supports the tire and the tire is removed together with the wheel, if the disk rotor is fixed to the wheel, the disk rotor is also removed together with the wheel when removing the tire. Therefore, if the caliper is provided so as to straddle the disk rotor and the pair of friction pads from the inner peripheral side, the caliper hinders the removal of the disk rotor and the pair of friction pads. It is desirable that the configuration be acceptable. When the disk rotor and the wheel are formed integrally, it is almost indispensable to provide a detachment permitting means, and even when they are formed separately, it is often desirable to provide the detachment permitting means. . When the wheel and the disk rotor are formed separately and fixed by the fastening means, if the fastening means is released, it is not necessary to remove the disk rotor when removing the wheel. Can be relatively easily removed without providing a removal permitting means. However, it is necessary to release the fastening means. Thus, it is desirable that both can be removed in the same manner as in the case where they are integrated, and that it is desirable to provide a removal permitting means. (4) The disc brake according to any one of (1) to (3), wherein the disc rotor is detachably attached to the wheel. According to this aspect, the disk rotor can be formed of a different material from the wheel, for example, a material having higher heat resistance and abrasion resistance than the wheel. Heat resistance and wear resistance can be improved at lower cost than in the case of forming. Further, when the disk rotor is worn, only the disk rotor needs to be replaced, and the replacement cost can be reduced as compared with the case where the disk rotor is replaced. Further, according to this aspect, it is not essential that the disk brake is configured as in the item (3), and as described in the embodiment of the invention, the disk brake is located on both sides of the pair of friction pads of the caliper and the disk rotor. Do 2
Even if the parts are integrally formed, the wheel and the disk rotor can be removed, and the caliper can be easily configured.

Another object of the present invention is to provide a wheel that is compact and has a large effective braking radius of the disk rotor. This problem is solved by configuring the wheel as described in the mode (5). (5) A disk portion that is generally disk-shaped and fixed to the rotating member, a rim portion that is generally cylindrical and provided integrally with an outer peripheral portion of the disk and supports a tire, and the rim thereof Extending radially inward from the inner peripheral surface of the part,
A wheel including an annular disk rotor. The disk rotor may be formed integrally with the wheel, or a disk rotor which is a member separate from the wheel may be fixed to the wheel. In the wheel, the disc portion and the rim portion may be integrally formed, or may be separately formed and fixed to each other.

[0005]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a disk brake provided on an idler wheel according to an embodiment of the present invention. In FIG. 1, reference numeral 10 denotes a bearing housing;
It has a cylindrical shape and is provided integrally with a steering knuckle as a non-rotating member (not shown). An axle 12 is held in the bearing housing 10 via a bearing 14 so as to be rotatable and immovable in the axial direction. An end of the axle 12 protruding from the bearing box 10 is provided with a flange-like axle hub 16 extending radially outward.
The wheel 22 is fixed concentrically.

[0006] The wheel 22 has a disk portion 24 and a rim portion 26 formed integrally. The disk portion 24 has a generally disk shape, and is fixed to the axle hub 16 by fastening means (for example, bolts) not shown. Rim part 2
6 has a generally cylindrical shape, and the rim portion 26 is concentric with the axle hub 16 when the wheel 22 is fixed to the axle hub 16.

An annular disk rotor 32 protrudes radially inward at an intermediate portion of the inner peripheral surface of the rim portion 26 in the center line direction. Friction surfaces 3 on both sides of disk rotor 32
Friction pads 38 and 40 are provided so as to face the respective discs 4 and 36, and a caliper 42 is provided so as to straddle the disk rotor 32 and the friction pads 38 and 40 from the inner peripheral side. The friction pads 38 and 40 are respectively formed by fixing friction materials 48 and 50 to back plates 44 and 46, respectively. The friction pad 38 is an inner pad disposed inside the disk rotor 32 in the width direction of the vehicle,
The friction pad 40 is an outer pad disposed outside, and these friction pads 38 and 40 are supported by a caliper 42 as described later.

The caliper 42 includes a cylinder member 54 and a reaction member 56, and is movably attached to the bearing housing 10 at the cylinder member 54. Supporting portions 60 extending radially outward from both ends separated in the axial direction are provided at two circumferentially separated locations on the outer peripheral surface of the bearing housing 10, respectively. In each case, a linear guide rod 62 serving as a guide member is supported so as not to rotate and not move in the axial direction. The guide rod 62 is provided in parallel with the center line of the bearing housing 10, that is, the rotation axis of the disk rotor 32 (hereinafter, simply referred to as the rotor rotation axis). As shown in FIGS. 1 and 2, the cylinder member 54 is provided with a pair of guided portions, which are leg portions 64, and is fitted to the two guide rods 62 so as to be slidable in the axial direction. ing. These leg portions 64 and support portions 6
Dust boots (not shown) are provided between the first and second surfaces, respectively, to prevent dust from entering the sliding surface.

The cylinder member 54 extends from the guide rod 62 to a position facing the friction surface 34 of the disk rotor 32 on the inner side in the width direction of the vehicle, and a cylinder bore 70 is formed in the extension. I have. A piston 72 is fitted to the cylinder bore 70 in a liquid-tight and slidable manner by being sealed by a seal member 74.
When the hydraulic pressure is supplied to the hydraulic chamber 76 formed between the piston 72 and the cylinder bore 70, the piston 72 moves forward.
Reference numeral 78 denotes a dust boot.

Support portions 80 are provided at both ends of the cylinder member 54 where the piston 72 is fitted in the rotation direction of the disk rotor 32 (hereinafter simply referred to as the rotor rotation direction) (FIG. 1). Only one support 80 is shown in FIG. Each of the support portions 80 extends parallel to the friction surface 34 of the disk rotor 32, and then extends parallel to the rotor rotation axis and toward the friction surface 34, and the back plate 44 of the friction pad 38. (FIG. 1 shows only one notch 82). The notch 82 is
4 are formed at both ends in the rotor rotation direction in parallel with the rotor rotation axis.
Are supported by the supporting portion 80 so as to be movable in a direction parallel to the rotor rotation axis and immovable in the rotor rotation direction.

The reaction member 56 is rotatably engaged with the cylinder member 54. The reaction member 56 is fixed to the cylinder member 5 by a plurality of bolts 84 which are a kind of fastening means.
4 is fixed. As shown in FIG. 2, the pair of leg portions 64 provided on the cylinder member 54 has opposite ends of the support shaft 86 at a portion outside the portion fitted to the guide rod 62 (on the side farther from the rotor rotation axis). The part is supported so that it cannot rotate and cannot move in the axial direction. The support shaft 86
The two guide rods 62 intersect at right angles at right angles, and are provided in parallel with the friction surfaces 34 and 36 of the disk rotor 32. The reaction member 56 is provided with an engagement portion projecting toward the rotor rotation axis. At 88, the support shaft 8
6 so as to be rotatable. Reaction member 56
Is in contact with the cylinder member 54 and the bolt 8
4 is fixed to the cylinder member 54. Bolt 8
In a state in which 4 is removed, the reaction member 56 is rotatable between an operating position facing the disk rotor 32 and a retracted position not facing the disk rotor 32.

As shown in FIG. 1, the reaction member 56 is extended from a portion fixed to the cylinder member 54 to a position opposite to the friction surface 36 located outside the disk rotor 32 in the vehicle width direction. It has a pressing portion 90.
Protrusions 92 protruding toward the disk rotor 32 are respectively provided at two positions of the pressing portion 90 separated in the rotor rotation direction, and two fitting holes formed on the back plate 46 of the friction pad 40. 94 (only one is shown in FIG. 1). The friction pad 40 is fixed to the pressing portion 90 by a bolt 96 which is a type of fastening means, and moves integrally with the reaction member 56.

The disk portion 24 of the wheel 22
As shown in FIG.
Are provided with holes 98 large enough to insert a tool to operate the bolt 84 and to remove the bolt 84. A plurality of holes 98 may be provided, or a long hole may be provided in the circumferential direction of the wheel 22.
4 is convenient for the attaching and detaching work.

When suppressing the rotation of the wheels, the hydraulic pressure chamber 76
Is supplied with hydraulic pressure. As a result, the piston 72 is advanced, the friction pad 38 is pressed against the friction surface 34 of the disk rotor 32, and the caliper 4
2 is moved in a direction opposite to the forward direction of the piston 72, and the pressing portion 90 presses the friction pad 40 against the friction surface 36 of the disk rotor 32, thereby suppressing the rotation of the wheel. The braking torque generated in the friction pad 38
The braking torque received by the caliper 42 due to the engagement of the friction member 40 with the support portion 80 is
Is received by the caliper 42 by the fitting between the and the protrusion 92. When the braking is released and the supply of the hydraulic pressure to the hydraulic pressure chamber 76 is released, the disk rotor 32 of the friction pads 38 and 40 is released.
Pressing to is released. When the piston 72 advances, the seal member 74 is elastically deformed, and when the supply of the hydraulic pressure is released, the piston 72 is moved away from the disk rotor 32 by the restoring force of the seal member 74.

When removing the wheel from the vehicle body, a bolt is removed by inserting a tool through a hole 98 provided in the disk portion 24 of the wheel 22. The hole 98 is moved to a position corresponding to the bolt 84 by rotating the wheel 22. When the bolt 84 is removed, the reaction member 56 can rotate with respect to the cylinder member 54. Next, when the bolts fixing the wheel 22 to the axle hub 16 are removed and the wheel 22 is moved away from the vehicle body, the reaction member 56 is rotated to the retracted position accordingly, and the removal of the disk rotor 32 is permitted. I do. If the disk rotor 32 is removed together with the wheel 22 in this way,
The friction pads 38, 40 can be removed from the cylinder member 54 and the reaction member 56.

When the wheel is mounted on the vehicle body, the pressing portion 90 of the reaction member 56 and the friction pad 40 are positioned between the disk rotor 32 and the disk portion 24 while the wheel 22 approaches the axle hub 16. To bring the wheel 22 into close contact with the axle hub 16. At this time, the pressing portion 90 and the friction pad 40 are pressed by the disk portion 24 and rotate to near the operation position. After the wheel 22 is fixed to the axle hub 16, a tool is inserted through the hole 98 to change the reaction member 56 to the cylinder member 54.
The bolt 84 is screwed and fixed to the cylinder member 54.

As described above, in the disc brake of the present embodiment, the disc rotor 32 is provided integrally with the wheel 22, and the caliper 42 is provided so as to straddle the disc rotor 32 and the friction pads 38, 40 from the inner peripheral side. As a result, the effective braking radius can be increased, a large braking torque can be obtained, and both ends of the guide rod 62 that supports the caliper 42 can be supported by the bearing housing 10. It is supported with high rigidity and can also serve as a mounting bracket. In the conventional disk brake in which the caliper straddles the disk rotor and the pair of friction pads from the outer peripheral side, since there is the disk rotor and the friction pads,
A guide member for guiding the movement of the caliper must be provided in a cantilever shape on the inner side of the vehicle with respect to the disc rotor, whereas if the caliper is provided so as to straddle the disc rotor and the pair of friction pads from the inner peripheral side, the There is no member that hinders the arrangement of the guide member on the inner peripheral side, and the caliper 42 can be supported with high rigidity by supporting both ends of the guide member. Further, the caliper 42 also serves as a torque receiving member for receiving the braking torque, and the disk rotor 32 is provided integrally with the wheel 22, so that the number of parts can be reduced.

As is clear from the above description, in the present embodiment, the bearing housing 10 forms a cylindrical member, the axle 12 forms a shaft member, and the caliper 42 is fixed to each other as an integrated caliper. Functional cylinder member 5
4 and a reaction member 56, and a structure in which the reaction member 56 is rotatably attached to the cylinder member 54 and can be moved to an operation position and a retreat position constitutes a retreat permitting means which is a kind of a detachment permitting means. doing.

In the above embodiment, the disk rotor 32
Is provided integrally with the wheel 22, but may be detachably fixed to the wheel 112 like a disk rotor 110 shown in FIG. The disk rotor 110 has a substantially U-shaped annular cross section, and has a U-shaped bottom wall 1.
14 is fitted inside the rim portion 116 on the outer peripheral surface,
It is positioned radially. Further, one side wall 118 of the U-shape is brought into close contact with the disk portion 120, is positioned in a direction parallel to the rotor rotation axis, and is fixed to the disk portion 120 by fastening means (for example, bolts) not shown. The other side wall 122 of the U-shape is the rim 1
The inner surface 16 extends radially inward from the inner peripheral surface, and both side surfaces function as friction surfaces 124 and 126, respectively. The caliper 130 has a pair of friction pads 38 and 40 and two portions located on both sides of the side wall 122, that is, a cylinder portion 136 and a reaction portion 138 are integrally formed. Other configurations are the same as those of the above-described embodiment, and corresponding portions are denoted by the same reference numerals and description thereof will be omitted.

When removing the wheels, the disk rotor 1
Remove the bolt that secures 10 to wheel 112 and the bolt that secures wheel 112 to axle hub 16. In this state, first, the wheel 112 is moved away from the vehicle body in a direction parallel to the rotor rotation axis and detached from the disk rotor 110. Next, the disk rotor 1
10 is moved in the radial direction while a pair of friction pads 38,
Remove from between 40 and remove. When the disk rotor 110 is removed, the friction pads 38 and 40 can be removed from the caliper 130. When mounting the wheels, first, while moving the disk rotor 110 in the radial direction,
22 is fitted between the pair of friction pads 38, 40, and then the disc rotor 110 is fitted inside the rim portion 116 of the wheel 112.
6 and the disk rotor 110 is fixed to the wheel 112.

When the caliper includes a cylinder member and a reaction member which are separate from each other, it is not essential that the reaction member be rotatably engaged with the cylinder member, but only fixed by a fastening means such as a bolt. You may. In this case, when removing the wheel, the fixing by the fastening means is released, and the reaction member is removed from the cylinder member to enable removal of the disk rotor and the pair of friction pads. Is provided with a hole large enough to allow the reaction member to enter and exit, the tool can be inserted through the hole to release the fastening of the fastening means, and the reaction member can be attached to and removed from the cylinder member.

In the above embodiment, the bearing housing 10
Is provided on a non-rotating member, and the axle 12 is rotatably fitted in the bearing housing 10. However, the bearing housing is rotatably mounted via a bearing outside a knuckle spindle constituting a steering knuckle. An axle hub may be provided on the box to fix the wheels.
In this case, a non-rotating member (for example, a steering knuckle)
The support portion extends from the disk to the disk rotor side to support the caliper.

Further, in the above embodiment, the friction pad is supported by the caliper. However, the friction pad may be supported by a mounting bracket. The mounting bracket is supported on the cylindrical member, and the mounting bracket supports the friction pad so as to be movable in a direction parallel to the rotor rotation axis and immovable in the rotor rotation direction.

Further, the caliper is not limited to the floating type in which the caliper moves in a direction parallel to the rotor rotation axis and presses the pair of friction pads against the friction surface of the disk rotor. A fixed type having a pair of cylinder portions disposed on both sides and pressing a pair of friction pads against friction surfaces by pistons may be used. Alternatively, a cylinder fixed caliper floating type having two pistons provided on a mounting bracket and calipers movably provided in a direction parallel to the rotor rotation axis may be used.

In the above embodiment, the case where the present invention is applied to the disk brake provided on the idler wheel has been described as an example. However, the present invention is also applied to the disk brake provided on the drive wheel. can do.

Further, the present invention can be implemented in a mode in which the combination of the constituent elements of the above embodiments is changed.
In addition, without departing from the scope of the claims, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a portion where a caliper of a disc brake according to an embodiment of the present invention is provided, and is a II sectional view in FIG. 2;

FIG. 2 is a front view (partial cross section) showing a portion of the disc brake provided with a caliper.

FIG. 3 is a side sectional view showing a portion provided with a caliper of a disc brake according to another embodiment of the present invention.

[Explanation of symbols]

22: Wheel 32: Disk rotor 34, 3
6: friction surface 38, 40: friction pad 42: caliper 110: disk rotor 112: wheel 124, 126: friction surface 130: caliper

Claims (1)

[Claims] 1. A disk rotor having an annular shape and having friction surfaces on both sides and rotating together with a wheel; a pair of friction pads slidably provided on the friction surfaces on both sides, respectively; A disc brake including a caliper provided so as to straddle a friction pad and a disc rotor, and pressing a pair of friction pads against corresponding friction surfaces, wherein the disc rotor is fixed to the wheel on an outer peripheral side, and radially inward. And a state in which the caliper straddles the disk rotor and the pair of friction pads from an inner peripheral side.