JP2002031171A - Disc brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost by isolating a pair of pads 9a and 9a in no-braking period by means of an automatically attachable spring 21 to prevent the backlash of the pads 9a and 9a and to facilitate the assembly work of a disk brake. SOLUTION: The spring 21 is equipped with a base 25 and a pair of elastic pieces 26 and 26. With this base 25 secured to the part of the inspection hole 20a of a caliper 4a, the locking sections 28 and 28 provided in the tip part of the elastic pieces 26 and 26 are locked to the locking hole 27 and 27 formed in the back plats 10 and 10 of the pads 9a and 9a. In this state, the springs 21 and 21 apply the elastic force to pad 9a and 9a in the separating direction from each other and the elastic force to the outer radial direction of a rotor 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The disc brake according to the present invention is used for braking an automobile. The present invention improves the ease of assembling a spring to such a disc brake.

[0002]

2. Description of the Related Art A disk brake having a structure as shown in FIGS. 6 to 8 is conventionally used as a disk brake for braking an automobile. The disk brake shown in FIGS. 6 to 8 is described in Japanese Patent Application Laid-Open No. 5-346125, and has a support 2 provided adjacent to one side of a rotor 1 which rotates together with wheels (not shown). Mounting holes 3 and 3 provided on the inner diameter side of this support 2 (the lower side of FIGS. 6 and 8).
To a suspension device (not shown). The caliper 4 is engaged with the support 2 by engaging a pair of guide pins 5, 5 fixed to the caliper 4 with a pair of guide cylinders 6, 6 provided on the support 2. (The front and back direction in FIG. 6, the up and down direction in FIG. 7, and the left and right direction in FIG. 8).

A part of the support 2 is provided with a pair of front and rear engagement portions 7 and 8 at a position separated in a circumferential direction of the rotor 1. Each of these engaging portions 7, 8
7A and 7B, the distal end is bent in a U-shape so as to straddle the outer peripheral portion of the rotor 1 in the vertical direction in FIGS. ing. Each of these pads 9, 9 is formed by attaching a lining 11 to one surface of a back plate 10, and engagement projections 12, 12 formed at both ends of the back plate 10 are respectively connected to the inflow side, By engaging the engaging grooves 13, 13 formed in the outgoing-side both engaging portions 7, 8, the rotor 1
Slidably in the axial direction.

Further, in a state of straddling the pads 9, 9,
The caliper 4 having a cylinder portion 14 and a caliper claw 15 is provided, and a piston 16 for pressing the pad 9 against the rotor 1 is built in the cylinder portion 14 among them. Further, between the outer peripheral edges of both ends of the back plates 10, 10 constituting the pads 9, 9 and the inner peripheral surface of the caliper 4, springs 17, 17 as shown in FIG.
Is provided. Each of the springs 17, 17 has insertion portions 18, 18 provided at both ends thereof inserted into insertion holes 19, 19 opened at the outer peripheral edges of both ends of the back plates 10, 10, respectively. In the state where the disc brake is assembled, the central portions of the springs 17, 17 are in contact with the inner peripheral surface of the intermediate portion of the caliper 4. In this state, these springs 17, 17
Gives the pair of pads 9 and 9 an elasticity that tends to move away from each other and an elasticity that is directed radially inward of the rotor 1. In addition, an inspection hole 20 is provided in the center of the caliper 4 to allow the inner and outer peripheral surfaces of the caliper 4 to communicate with each other. This inspection hole 20 corresponds to the hole described in claim 1.
Are provided so that the thickness of the linings 11 and 11 of the pads 9 and 9 can be visually checked to determine the replacement time of the pads 9 and 9.

When the vehicle is braked by the disk brake as described above, pressure oil is fed into the cylinder portion 14 as the brake pedal is depressed, and one side (inner side, FIG. Upper side, FIG. 8
Pad 9 on one side (inner side,
7 (the left side in FIG. 8). The caliper 4 moves the piston 16
Direction opposite to the extrusion direction (upper in FIG. 7, leftward in FIG. 8)
The caliper claw 15 provided on the caliper 4 is displaced to the other pad 9 (outer side, lower side in FIG. 7, right side in FIG. 8).
Is pressed against the other side surface (outer side surface, lower surface in FIG. 7, right side surface in FIG. 8) of the rotor 1. As a result, a pair of pads 9, 9
Strongly clamps the rotor 1 from both sides, and braking is performed based on the frictional force acting between the linings 11, 11 constituting these pads 9, 9 and both side surfaces of the rotor 1.

When the braking is released, the force pressing the pads 9, 9 against the rotor 1 is lost with the release of the pressurized oil into the cylinder portion 14, and these pads 9, 9 The springs 17 are displaced in directions away from each other based on the elasticity of the springs 17. As a result, each of the pads 9,
9 does not rub against the side surfaces of the rotor 1. As described above, in order to prevent the side surfaces of the rotor 1 and the linings 11 and 11 from rubbing each other during non-braking, so-called dragging, the rotational resistance of the wheels during non-braking is reduced, and the power performance and fuel efficiency of the vehicle are improved. Can be achieved.
At the same time, the wear of the linings 11, 11 is suppressed, and uneven wear in which the thickness of the linings 11, 11 is greatly different at both ends in the circumferential direction is prevented. Further, at the time of non-braking as described above, each of the springs 17, 17 presses each of the pads 9, 9 radially inward of the rotor 1 so that
These pads 9, 9 are prevented from rattling against the caliper 4, and unpleasant vibration and noise are prevented from being generated.

[0007]

In the case of the conventional structure shown in FIGS. 6 to 9, the function of preventing drag and the function of preventing vibration and noise are sufficient, but the work of assembling the springs 17, 17 is troublesome, and the cost is reduced. Inevitably increases. That is, these springs 17 need to be assembled to the back plate 10 of each pad 9, 9 before the caliper 4 is assembled to the support 2. The work of assembling the caliper 4 to the support 2 is performed by the respective springs 1.
It must be done while elastically displacing the springs 7 and 17 and paying attention so that the mounting positions of the springs 17 and 17 are proper. Since such operations are troublesome and difficult to automate, the cost of assembling the disc brake increases, and the cost of the disc brake increases due to the increase in the number of parts associated with the use of one pair of the springs 17, 17 described above. It has become. The disc brake of the present invention has been invented in view of such circumstances.

[0008]

A disk brake according to the present invention, like a conventionally known disk brake, includes a support fixed to a vehicle body over a rotor that rotates with wheels, and a support attached to the support in the axial direction of the rotor. And a pair of pads each having a lining attached to one surface of a back plate, a caliper supported by the support, and a piston built into the caliper. Then, with the pushing of the piston, the rotor is clamped by the pair of pads to perform braking.

In particular, in the disc brake according to the present invention, a hole provided in a portion of the caliper facing a portion of the lining of the pair of pads,
A spring provided between the back plate of the pair of pads. The spring has a base that can be locked at the caliper outer peripheral surface side opening of the hole, and protrudes from the base toward the inner peripheral surface of the caliper. And a pair of elastic pieces engaged with the pad, the elasticity in a direction to widen the space between the pair of pads, and the elasticity in a direction to draw both pads toward the hole and radially outward of the rotor. And

[0010]

In the disk brake of the present invention constructed as described above, a pair of elastic pieces constituting a spring separates a pair of pads when the brake is not applied, so that both side surfaces of the rotor and the lining of each pad are separated. Prevent rubbing. Further, since each of the elastic pieces attracts each of the pads outward in the radial direction of the rotor, it is possible to prevent the pads from rattling against the support during non-braking. In addition, in the case of the disc brake of the present invention, the base of the spring having the above-described function is
This spring can be assembled after the caliper has been assembled to the support, since the spring is locked to the caliper outer peripheral surface side opening. For this reason, it becomes possible to automate the operation of assembling the spring.

[0011]

1 to 4 show an example of an embodiment of the present invention. A feature of the present invention relates to a structure of an assembly portion of a spring 21 for imparting a desired elasticity to a pair of pads 9a, 9a provided with the rotor 1 interposed therebetween. In addition, the entire structure of the disc brake includes the conventional structure shown in FIGS. 6 to 8 and is the same as a conventionally known general disc brake. In the following, description will be made focusing on features of the present invention.

An inspection hole 20a corresponding to the hole described in claim 1 is provided at the center of the caliper 4a in such a manner that the inner and outer peripheral surfaces of the caliper 4a communicate with each other. The thickness of the linings 11a, 11a is made visible. In the case of this example, the inspection hole 20 is used.
a is a pair of stepped portions 24, 24 provided with a wide portion 22 located on the outer diameter side half and a narrow portion 23 located on the inner diameter side half with the narrow portion 23 interposed therebetween. , Continuous
It has a stepped shape. Each of the steps 24 is a flat surface located on the same plane.

The spring 21 is provided between the inspection hole 20a as described above and the back plates 10a, 10a constituting the pads 9a, 9a, and these pads 9a, 9a
And an elasticity in a direction in which the distance between the two pads 9a, 9a is directed toward the inspection hole 20a and a direction in which the pads 9a are attracted radially outward (upward in FIGS. 1 and 2) of the rotor 1. are doing.

As shown in FIG. 4, the spring 21 is formed by bending a resilient wire, such as a stainless steel wire, and has one base 25 and And a pair of elastic pieces 26, 26 bent radially inward of the rotor 1 (below FIGS. 1, 2, and 4) from both ends of the base 25. The base portion ₂₅ has a width W ₂₅ larger than the width W _{23 of the} narrow portion 23 so that the base portion 25 can be bridged between the pair of steps 24 provided in the inspection hole 20a. At the same time, the lining 11a has a shape that does not obstruct the visual inspection of the lining 11a through the inspection hole 20a. For this reason, in the illustrated example, the base 25
Is formed in a waveform by alternately bending the wire in the opposite direction.

On the other hand, each of the elastic pieces 26, 26
Are bent radially inward of the rotor 1 from the center in the width direction at both ends in the longitudinal direction of the base 25 (left and right directions in FIGS. 1 and 4 and front and back directions in FIG. 2). Then, the back plates 10a, 10 described below are attached to the distal ends of the elastic pieces 26, 26, respectively.
a locking portion 28 for inserting and locking into the locking holes 27
28 are formed by bending the distal ends of the elastic pieces 26, 26 in directions opposite to each other. Such a spring 2
The elastic pieces 26, 26 are provided with elasticity in a direction in which the interval between the locking portions 28, 28 formed at the respective distal end portions in the free state is widened.

The elastic piece 2 constituting the spring 21 as described above
In order to engage with the pads 6 and 26 and the locking portions 28 and 28, the center of the length direction (the front and back direction in FIG. 1 and the left and right direction in FIG. 2) of one surface of the back plates 10a and 10a constituting the pads 9a The portion is provided with a portion to which the linings 11a and 11a are not attached. In other words, each of the back plates 10a, 1
A pair of linings 11a, 11a on one side of
Are attached to each other at an interval from each other, so that the lining 1
Each of these back plates 10a, 10a,
The groove portions 29, 29 where a is exposed are formed. The width W ₂₉ of each of the groove portions 29 is equal to that of each elastic piece 2.
Larger than the outer diameter D ₂₆ of 6, 26 and (W _29> D _26),
These elastic pieces 26, 26 can freely enter the respective groove-like portions 29, 29.

The central portions of the back plates 10a, 10a in the length direction (the bottom portions of the groove portions 29, 29) are slightly closer to the outer diameter than the central portions in the width direction. Stop holes 27, 27 are formed. Each of these locking holes 27,
Reference numeral 27 has an inner diameter into which each of the locking portions 28 can be inserted. Further, the formation positions of the locking holes 27 in the radial direction of the rotor 1 are regulated as follows. That is, the back plate 1 of the pad 9a facing the piston 16
The position of the locking hole 27 formed in the piston 1
In the contact portion between the front end surface of the rotor 6 and the back surface of the back plate 10a, the contact portion is present in the radially inner portion of the rotor 1 rather than the outermost portion in the radial direction of the rotor 1.
Regarding the other pad 9a as well,
The locking hole 27 is formed. The reason for this is to use the same kind of pads 9a, 9a, and to assemble the disc brake easily without limiting the direction in which the spring 21 is assembled. Further, each of the back plates 10
a, each of the locking holes 27, 27 at the center in the longitudinal direction.
A part of each of the resilient pieces 26, 26 is provided between the outer peripheral edge of each of the back plates 10a, 10a.
0 is formed. The depth D of each of these relief grooves 30, 30
₃₀ is equal to or greater than the outer diameter D ₂₆ of each of the elastic pieces 26, ₂₆ (D ₃₀ ≧
D ₂₆ ).

In the disk brake of the present invention having the above-described structure, the pair of elastic pieces 26, 26 constituting the spring 21 separates the pair of pads 9a, 9a from each other when the brake is not applied. 1 and both pads 9a,
The linings 9a of 9a are prevented from rubbing against each other. The respective elastic pieces 26, 26 correspond to the respective pads 9a, 9
a of the back plates 10a and 10a, which are arranged in the longitudinal direction, are pressed by the single elastic pieces 26 and 26, respectively, so that each of the linings 11a and 11a is pressed. The whole can be separated from both side surfaces of the rotor 1.

The position at which the elastic pieces 26, 26 press the pads 9a, 9a is determined by the diameter of the rotor 1 in the contact portion between the tip end surface of the piston 16 and the back surface of the back plate 10a. The direction of the rotor 1
The inner portion (left side in FIG. 1) of the pad 9a pressed by the distal end surface of the piston 16 does not incline based on the pressing force of the elastic piece 26. That is, with respect to the inner side pad 9a, this pressing force is applied to the pad 9a.
The rear surface of the back plate 10a is pressed against the distal end surface of the piston 16 and acts in a stabilizing direction, so that the inner side pad 9a does not tilt.

The spring 21 is provided at the distal end of each of the elastic pieces 26, 26 in a state where the base 25 and the elastic pieces 26, 26 are elastically deformed inward in the radial direction of the rotor 1. The locking portions 28, 28 are connected to the locking holes 27, 2, respectively.
7. In this state, each of the elastic pieces 26, 26
Is in a state in which the radial elasticity of the rotor 1 is applied. Accordingly, each of the pads 9a, 9a is pulled radially outward of the rotor 1 at the central portion in the longitudinal direction, thereby preventing the engaging portion with the support 2 from rattling.

In the case of the disc brake of the present invention, as described above, drag is prevented from occurring during non-braking, and the pads 9a, 9a
Prevent rattling. In particular, in the case of the disc brake of the present invention, since the mounting operation of the spring 21 having the above-described function can be performed after the support 2 and the caliper 4a are combined, the mounting operation of the spring 21 is automated. It is possible to do. That is, when the spring 21 is mounted, the elastic pieces 26, 26 are inserted into the inspection hole 2 while the distance between the pair of elastic pieces 26, 26 is reduced.
0a to the inner peripheral surface side of the caliper 4a. Then, the locking portions 28, 28 provided at the distal ends of the elastic pieces 26, 26 have entered the groove portions 29, 29 of the pads 9a, 9a previously mounted on the support 2. If so, the force that shortened the interval between the elastic pieces 26, 26 is released. As a result, each of the locking portions 2
8 and 28 abut against the bottom surfaces of the escape grooves 30 and 30 formed in the outer diameter half of each of the groove portions 29 and 29 by their own elasticity.

Then, in this state, the central portion in the width direction of the base 25 constituting the spring 21 is pushed toward the inner diameter side of the rotor 1. By this operation, each of the locking portions 28, 28
Moves radially inward of the rotor 1 along the bottom surfaces of the groove portions 29, 29 and reaches the locking holes 27, 27. Then, in a state where the locking portions 28, 28 are aligned with the locking holes 27, 27, the locking portions 2
8, 28 enter the respective locking holes 27, 27. In this state, the base 25 is elastically curved and deformed in a direction in which the inner diameter side of the central portion in the width direction becomes convex. Therefore, the elastic pieces 26, 26 are provided with elasticity directed radially outward of the rotor 1.

As described above, the operation of bridging the spring 21 between the caliper 4 and the pair of pads 9a, 9a is as follows.
Automatically using an assembly robot. For this reason, the cost can be reduced by increasing the efficiency of the assembling work, in combination with the reduction in the number of parts involved in using only one spring 21.

If the linings 11a are worn by repeated braking, the elastic pieces 2a
The distance between 6, 6 and both side surfaces of the rotor 1 is reduced. In such a state, the first half of each of the elastic pieces 26, 26 enters into each of the clearance grooves 30, 30, and the
a, 10a does not protrude from one side. Therefore, it is possible to prevent the elastic pieces 26, 26 from rubbing against the rotor 1, thereby preventing the side surface of the rotor 1 from being damaged, and preventing the linings 11a, 11a from being effectively used.

In the above-described embodiment, the spring 21 is formed by bending a wire to form a single body.
As shown in FIG. 5, an integral spring 21a formed by bending a band-shaped plate can be used. However, when the base is a spring 21a made of a plate material, it is difficult to elastically deform the base 25a in the radial direction of the rotor. Therefore, each elastic piece 26
a, 26a, elastic deformation portions 31, 31 are provided at the base end portion,
These elastic pieces 26a, 26a at the tip of the 26a,
8a is imparted with a radially outward elastic force of the rotor. Of course, in the case of a spring made of a wire, a similar elastically deformable portion may be provided.

[0026]

Since the disk brake of the present invention is constructed and operates as described above, the cost can be reduced by reducing the number of parts and increasing the efficiency of the assembly work.

[Brief description of the drawings]

FIG. 1 is an illustration of an embodiment of the present invention, with some parts omitted;
FIG. 9 is a schematic cross-sectional view showing a state viewed from the same direction as FIG. 8.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a perspective view showing a central portion of an outer peripheral surface of a caliper.

FIG. 4 is a perspective view showing a first example of a spring provided between a pair of pads and a caliper.

FIG. 5 is a perspective view showing the second example.

FIG. 6 is a front view showing an example of a conventionally known disc brake.

FIG. 7 is a view as seen from above in FIG. 6;

FIG. 8 is a sectional view taken along line BB of FIG. 6;

FIG. 9 is a perspective view of a spring incorporated in a conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2 Support 3 Mounting hole 4, 4a Caliper 5 Guide pin 6 Guide cylinder part 7 Entrance side engagement part 8 Entrance side engagement part 9, 9a Pad 10, 10a Back plate 11, 11a Lining 12 Engagement projection DESCRIPTION OF SYMBOLS 13 Engagement groove 14 Cylinder part 15 Caliper claw 16 Piston 17 Spring 18 Insertion part 19 Insertion hole 20, 20a Inspection hole 21, 21a Spring 22 Wide part 23 Narrow part 24 Step part 25, 25a Base 26, 26a Elastic piece 27 Stop holes 28, 28a Locking portion 29 Groove portion 30 Escape groove 31 Elastic deformation portion

Claims (3)

[Claims] 1. A pair of supports fixed to a vehicle body across a rotor that rotates with wheels, and a pair of supports supported by the supports so as to be freely displaceable in the axial direction of the rotor, each having a lining attached to one surface of a back plate. A disc brake, comprising a pad, a caliper supported by the support, and a piston built into the caliper, and performing a braking operation by holding the rotor by the pair of pads as the piston is pushed out. , A part of the caliper
A hole provided in a portion opposing a part of the lining of the pair of pads; and a spring provided between the hole and the back plate of the pair of pads. A base that can be locked to the opening, and a pair of elastic pieces that continuously project from the base to the inner peripheral surface side of the caliper and have their respective tips engaged with a part of the back plate of each of the pads. Wherein the pad has an elasticity in a direction in which a distance between the pair of pads is widened, and an elasticity in a direction in which both pads are directed toward the hole and is attracted radially outward of the rotor. Disc brake to do. 2. A portion of a back plate constituting each pad, to which no lining is attached, is provided with a locking hole for locking a distal end portion of each elastic piece. 2. The disc brake according to claim 1, wherein a part of said elastic piece forms an escape groove between said locking hole and an outer peripheral edge of said back plate. 3. The position of an engaging hole formed in the back plate of the pad facing the piston is equal to the position of the contact portion between the front end surface of the piston and the back surface of the back plate than the outermost portion in the radial direction of the rotor. The disk brake according to any one of claims 1 to 2, wherein the disk brake is also present in an inner portion in a radial direction of the rotor.