JP2002195317A - Disc brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure proper and smooth follow-up performance of a pad to the rocking of a disc by enhancing the degree of freedom of setting a rocking range of the pad, in a disc brake device that is so composed as to always press the pad against the disc in parallel with each other. SOLUTION: This disc brake device is provided with a housing hole 38 formed in a caliper 30 as a support mechanism for the pad 33a (33b) so as to extend in a pressing direction of the pad 33a (33b), and a support member 40 having a part housed in the hole 38. A space (m) for permitting the support member 40 to rock in a predetermined region around a fulcrum P imagined on the pad 33a (33b) side on the same axis as that of the support member 40 is formed between the outer periphery of the support member 40 and the inner periphery of the hole 38. A spherical contact part 39 having a radius R of curvature centering the rocking fulcrum P of the support member 40 is formed between the bottom face of the hole 38 and the rear end of the support member 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc brake device used for railway vehicles and the like.

[0002]

2. Description of the Related Art Disc brake devices as shown in FIGS. 5 and 6 are disclosed as means for braking a railway vehicle or the like (see Japanese Patent Application Laid-Open No. 10-267058). In FIG. 5, reference numeral 1 denotes a caliper of a disc brake device, which is mounted on a mounting portion 2 fixed to a chassis (a chassis frame) via a support pin 3 so as to be movable in the axle direction. A pair of arms 1a and 1b of the caliper 1 are formed so as to extend around both sides of the wheel 4, and pads 5a and 5b (a brake shoe) are mounted on these arms 1a and 1b via support mechanisms, respectively.

The pads 5a and 5b are provided with flat friction surfaces, and are supported on both sides of the wheel 4 so as to face the disk 4a which rotates integrally with the wheel 4. Arm 1a
5 (extends in a direction perpendicular to the plane of FIG. 5).
The piston 6 (see FIGS. 6 to 8) is housed in a symmetrical position with respect to the center line of the pad 5a as a means for pressing the a and 5b against the disk 4a. The pad 5a is pressed against the disk 4a. Since the caliper 1 moves along the support pin 3, the pads 5a and 5b on both sides sandwich the disc 4a, and a braking force (frictional force) is applied to the rotation of the wheel 5. 3a and 3b initially (neutral) the caliper 1 movable along the support pin 3 with respect to the mounting portion 2 fixed to the chassis.
It is a return spring that urges to a position.

When the pads 5a and 5b are inclined and pressed against the disk 4a, the braking force applied to the wheel 4 is weakened, and uneven wear is easily generated on the friction surfaces of the pads 5a and 5ab. In order to prevent this, the support mechanism of the pads 5a and 5b is described in the case of the arm 1a having the piston 6,
It is configured as shown in FIGS. In FIG. 6, the cylinder 7 extending in the pressing direction of the pad 5a is the arm 1a.
(Caliper), and a liner portion 9 slidable via an O-ring 8 is provided inside the cylinder 7. The liner portion 9 is provided with a receiving hole 10 opened on the front surface thereof, and the head portion 12 (a support member of the pad 5 a) is supported in the receiving hole 10 via a spherical bearing 11.

Since the head portion 12 can swing about the center of the spherical bearing 11 as a fulcrum, the relative inclination of the pad 5a generated between the head portion 12 and the disk 4a is absorbed, and the friction surface of the pad 5a is parallel to the disk 4a. It is pressed against. 13
Is a heat insulating plate that forms a support surface for suppressing the back surface of the pad 5a, and is attached to the tip of the head unit 12. 14a, 14
Reference numeral b denotes a stopper for locking the outer member of the spherical bearing 11 to the liner portion 9 and the inner member to the head portion 12.

In FIG. 7, the head portion 12 and the accommodation hole 1 are shown.
A gap (clearance) that allows the head portion 12 to swing is set between 0 and 0. A tapered surface 15 that reduces the diameter of the hole to the bottom is formed at the inner corner of the housing hole 10, and a curved surface 16 that is in contact with the tapered surface 15 is formed at the rear edge of the head 12. The head portion 12 is prevented from coming out of the housing portion 10 by the stopper 17 and swings around the stopper 17 in one direction (a direction orthogonal to the paper surface of the drawing) while sliding the curved surface 16 to the tapered surface 15. The friction surface of the pad 5a is pressed in parallel to the disk 4a (see the figure). 7, the same components as those in FIG. 6 are denoted by the same reference numerals.

In the case of FIG. 6, the spherical bearing 11 is
Is supported in the radial direction, so that when the thrust (acting force of the piston) acting on the liner portion 9 in the substantially axial direction is received, the inner member is easily detached from the outer member, and the spherical surface is formed on one side (substantially half surface).
In this case, since the sliding can be performed while supporting a large thrust, uneven wear easily occurs, and it is difficult to ensure durability and reliability.
In the case of FIG. 7, since the swing of the head portion 12 is limited to one direction, only when the relative inclination direction of the pad 5a generated between the pad 4a and the disk 4a is constant, such as at the time of cornering of a vehicle, Although the inclination can be effectively absorbed, the pad 5
In the case where the disk 4a swings irregularly with respect to a (for example, there is a tolerance in the mounting of the disk 4a, the disk 4a rotates while swinging left and right in the traveling direction), It is also conceivable that the pad 5a is inclined and pressed.

In FIG. 8, concave portions 18a and 18b (formed in a substantially conical shape having a deepest portion at the center) are provided coaxially on the bottom surface of the accommodation hole 10 and the rear end surface of the head portion 12, and these concave portions 18a and 18b are provided. A sphere 19 (ball) is interposed so as to roll freely. A gap (clearance) is set between the head section 12 and the accommodation hole 10 to allow the head section 12 to swing. Since the head portion 12 can swing around the sphere 19, the disc 4a
Even if (see FIG. 3) swings irregularly, the friction surface of the pad 5a is pressed against the disk 4a in parallel. Reference numeral 20 denotes an O-ring that seals a gap between the inner periphery of the housing and the outer periphery of the head. 8, the same components as those in FIG. 6 are denoted by the same reference numerals.

In FIG. 5, the other arm 1
As for b (the piston is not accommodated), an accommodation hole (see 10 in FIGS. 6 to 8) is formed in the caliper 1 (arm 1b), and a support member for the pad 1b (see FIG. 6).
8 to 12) are accommodated in the accommodation hole. And
Spherical bearing 11 between housing hole and support member (see FIG. 6)
Alternatively, a tapered surface 15 and a curved surface 16 (see FIG. 7) or concave portions 18a and 18b and a sphere 19 (see FIG. 8) are provided. That is, although the liner portion 9 and the cylinder 7 in FIGS. 6 to 8 are not provided, other components are configured in the same manner as in FIGS. 6 to 8.

[0010]

In the case of FIG. 8, the gap set between the head portion 12 and the receiving hole 10 is a sphere 19
Therefore, it is difficult to set the swing angle of the head section 12 (the swing range of the pad 5a) to be large. For example,
In FIG. 8, the diameter r of the sphere 19 is 9 mm, the gap m is 2 mm,
Assuming that the swing radius d of the head 12 is 30 mm, the gap n required to allow the maximum swing angle θ of the head 12 is 0.5 mm.
Tan θ = 0.5 / 30 = 0.017, the head part 12
Is limited to a very small value of 0.57 °. Further, the thrust for pressing the liner portion 9 is formed by the concave portions 18a, 1a.
8b, the surface pressure of these contact portions becomes excessive, and the pad 5a against the swing of the disk 4a.
The tracking performance of the (head unit 12) cannot be sufficiently obtained. In addition, the small-diameter sphere 19 requires precise spherical processing, and the space between the head 12 and the liner 9 (recesses 18a, 18b).
There is a problem that it is troublesome to incorporate it into the system.

The present invention has been made in view of such a problem, and has a high degree of freedom in setting the swing range of the pad, and provides a good and smooth follow-up performance of the pad to the swing of the disc. The purpose is to provide a brake device.

[0012]

According to a first aspect of the present invention, there is provided a disk rotating integrally with a wheel, a caliper mounted on a chassis, a pad mounted on the caliper via a support mechanism in a state facing the disk, and a pad. Means for pressing the disc against the disc,
The pad support mechanism includes a receiving hole provided to extend in a direction in which the pad is pressed against the caliper, and a supporting member partially accommodated in the hole. And a gap allowing the support member to swing within a predetermined range around a fulcrum imagined on the pad side coaxially with the support member, and a gap between the bottom surface of the accommodation hole and the rear end of the support member. The present invention is characterized in that a spherical contact portion having a radius of curvature centered on the swing fulcrum of the support member is set therebetween.

According to a second aspect, in the disk brake device according to the first aspect, the means for pressing the pad against the disk includes a piston for driving the pad in the pressing direction when fluid pressure is supplied, while the piston is provided with a pad. A head portion forming a support member, a liner portion forming an accommodation hole, and a cylinder for supporting the liner portion on the caliper slidably in the pad pressing direction so as to function as a support mechanism. Features.

According to a third aspect of the present invention, in the disk brake device according to the first aspect, the swing fulcrum of the support member is set at a position half the pad wear allowance. Disc brake device.

According to a fourth aspect, in the disk brake device according to the first aspect, the spherical contact portion includes a concave portion on the side of the receiving hole and a convex portion on the supporting member side, and the concave portion is formed in the receiving hole. It is characterized by being formed by fitting.

[0016]

According to the first aspect of the present invention, the pad supporting mechanism allows the supporting member to swing freely around the fulcrum on the pad side along the spherical contact portion between the supporting member and the receiving hole, thereby allowing the disk to swing ( Even when the inclination is irregular in three dimensions, the friction surface of the pad is pressed against the disk in parallel. The spherical contact portion receives the pressing force of the pad, but its radius of curvature is centered on the swing fulcrum of the support member, so a large contact (sliding) area between the bottom surface of the receiving hole and the rear end of the support member. Can be secured. Therefore, the contact pressure of these contact portions is suppressed to a small value, and the pad follows the swinging of the disk smoothly without difficulty. The swing range (maximum swing angle) of the pad can be set arbitrarily (freely) by the radius of curvature of the spherical contact portion within the allowable range of the gap.

In the second invention, a pad supporting mechanism is assembled to a piston for pressing a pad against a disk. The piston head can swing freely along the spherical contact part between the piston head and the liner receiving hole around the fulcrum on the pad side, and the piston liner slides inside the cylinder in the pad pressing direction during braking. When the piston (stretching action) is performed, the frictional surface of the pad is pressed in parallel to the disk even when the disk swings (tilts) irregularly in three dimensions, and the same effect as in the first invention is obtained. Can be

In the third aspect of the invention, when the pad is worn, the spherical contact portion is displaced toward the disk with the progress (amount of wear). Since the maximum displacement of the pad is contained, the influence of the progress of the wear of the pad on the following performance can be minimized.

In the fourth aspect, the concave portion on the side of the receiving hole may be formed integrally with the liner portion. However, by fitting a separate concave portion on the bottom surface of the receiving portion, the inner surface of the receiving hole is formed. Even when processing is performed on the portion (bottom surface), precision processing of the spherical contact portion can be performed easily and efficiently.

[0020]

1 to 3 show an embodiment according to the present invention. In FIG. 1, reference numeral 30 denotes a caliper of the disc brake device, which is fixed to a chassis (an undercarriage frame) via a mounting portion 31 formed at a central portion thereof. The pair of arms 30a and 30b of the caliper 30 are formed so as to extend around both sides of the wheel 32, and the arms 30a and 30b are respectively connected to the pads 3 via a support mechanism.
3a and 33b are mounted. The pads 33a and 33b are provided with flat friction surfaces, and are supported on both sides of the wheel 32 so as to face the disk 32a that rotates integrally with the wheel 32.

As means for pressing the pads 33a, 33b against the disk 32a at the tips of the arms 30a, 30b (extending in the direction perpendicular to the plane of the paper of FIG. 1), a piston 34 (see FIGS. 2, 3) is attached to the pads 33a, 33b. When accommodated in a symmetrical position across the center line and supplied with fluid pressure, the pads 33a, 33b are pressed by the disk 32a by the extension action of the piston 34, and a braking force (frictional force) is applied to the rotation of the wheels. .

The piston 34 for driving the pads 33a and 33b in the direction of pressing against the disk 32a is
a, 33b are configured to function as a support mechanism. 2 and 3, a cylinder 35 extending in the pressing direction of the pad 33a (33b) is connected to the arm 30a (30).
A liner 37 is formed inside the cylinder 35 and is slidable via an O-ring 36. The liner portion 37 is provided with a housing hole 38 opened on the front surface thereof, and the head portion 40 (a support member for the pad 5a) is swingably supported in the housing hole 38 via a spherical contact portion 39 described later.

The pad 33a (33b) is coaxial with the head 40 between the outer periphery of the head 40 and the inner periphery of the receiving hole 38.
A gap m (clearance) is provided to allow the head portion 40 to swing within a predetermined range about a fulcrum P imagined on the side, and a spherical surface is provided between the bottom surface of the housing hole 38 and the rear end of the head portion 40. The contact portion 39 is set. The spherical contact portion 39 is composed of a convex surface 39 a formed at the rear end of the head portion 40 and a concave surface portion 39 b attached to the bottom surface of the accommodation hole 38, and these contact surfaces are centered on the pivot point P of the head portion 40. Is formed on a spherical surface having a radius of curvature R. Reference numeral 42 denotes an O-ring that seals the gap m.
(The diameter of the head portion 40 is reduced). The head portion 40 is formed of a heat insulating material, and suppresses transmission of frictional heat to the liner portion 37 during braking (when the pads 33a and 33b are pressed against the disk 32a).

As described above, since the caliper 30 is fixed to the chassis, the disc
The pistons 34 are provided at 0a and 30b. In FIG. 2, the pad 33a (33b) is
Means 43 (tentatively referred to as a pad return device) for biasing the arm 30a to an initial position away from the arm are disposed at both ends of the distal end portion of the arm 30a (30b) (extending in a direction orthogonal to the plane of FIG. 1). The pad return device 43 includes an outer cylindrical portion 43a and an inner cylindrical portion 43b.
A cap 43c for closing the bottom of the outer cylinder 43a, a shaft 43d standing upright at the center of the inner surface of the cap 43c, and an inner cylinder 4
3b, a cylindrical spring receiver 43f formed on the inner periphery of the shaft 3b, and a shaft 43d.
, A spring receiver 43g formed on the tip of the cap 43c, a spring receiver 43g formed on the cap 43c, a return spring 43h interposed between the spring receiver 43e and the spring receiver 43f, and between the spring receiver 43g and the spring receiver 43f. 43i.

The outer cylinder 43a is fixed to the arm 30a (30b), and the inner cylinder 43b, whose tip abuts against the back plate 44 of the pad 33a (33b), has a pad 33a (33).
b) is locked to a mounting plate 45 (connected to the back plate 44 by rivets 47 via spacers 46) disposed on the back side of FIG. 4
Reference numerals 8 and 49 denote dust seals, 50 denotes a heat insulating plate coupled to the tip of the head section 40, and the tip of the heat insulating plate is a pad 33a (33).
The support surface which abuts on the mounting plate 45 of b) is formed. FIG.
In the figure, reference numeral 51 denotes a fluid pressure passage which enters and exits the cylinder 35, and is connected to the valve 52 of FIG. 1 through the arms 30a and 30b.

With such a configuration, the pads 33a (3
The head portion 40 (support member) can swing freely along the spherical contact portion 39 between the receiving hole 38 and the accommodation hole 38 around the fulcrum P on the 3b) side, and the swing (tilt) of the disk 32a is irregular in three dimensions. In such a case, the pad 33a (3
The friction surface of 3b) is pressed in parallel. Spherical contact part 3
9 receives the pressing force of the pads 33a (33b). Since the radius of curvature R is centered on the swing fulcrum P of the head 40, the gap 9 is located between the bottom surface of the receiving hole 38 and the rear end of the head 40. A large contact (sliding) area can be secured. For this reason, the surface pressure of these sliding parts is kept small, and the disc 3
The pad 33a (33b) follows the swing of 2a without difficulty and smoothly.

The swing range (maximum swing angle θ) of the pads 33a (33b) can be set arbitrarily (freely) by the radius of curvature R of the spherical contact portion 39 within the allowable range of the gap m. For example, when the radius of curvature R of the spherical contact portion 39 is set to 47 mm, the maximum swing angle θ of the pad 33a (33b) is equal to 1.
30 ° can be obtained. When the pads 33a (33b) are worn, the position of the spherical contact portion 39 at the time of braking changes toward the disk 32a (wheel) according to the degree of progress (amount of wear), but the swing fulcrum P of the head portion 40 is moved to the pad 33a. (33
If the wear margin S is set at a half position of the wear margin S, the swing fulcrum P of the head part 40 is reduced to half of the maximum displacement of the spherical contact part 39.
, The influence of the wear progress on the following performance of the pad 33a (33b) can be minimized. In the spherical contact portion 39, the concave portion 39b on the side of the receiving hole 38 may be formed integrally with the liner portion 37 as shown in FIG.
8 can easily and efficiently process precise spherical processing.

The present invention relates to a case where the arm 30a (30b) is not provided with the piston 34 (for example, the arm 1 in FIG. 5).
Application to b) is also possible. Although not shown, a receiving hole (see 38 in FIG. 3) is formed in the arm, and a pad support member (see 40 in FIG. 3) is housed in the receiving hole. Then, a gap m and a spherical contact portion 39 as shown in FIG. 3 are set between the accommodation hole and the support member. That is, the liner portion 37 and the cylinder 35 in FIG. 3 are omitted, but the other components are configured in the same manner as in FIG. It is swingably supported along the spherical contact portion.

[Brief description of the drawings]

FIG. 1 is a front view of a disc brake device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a sectional view of an essential part of the same.

FIG. 4 is a cross-sectional view of a principal part explaining another embodiment.

FIG. 5 is a front view of a disc brake device showing a conventional example.

FIG. 6 is a sectional view of an essential part of the same.

FIG. 7 is a sectional view of another main part of the same.

FIG. 8 is another cross-sectional view of the main part.

FIG. 9 is a cross-sectional view of a main part illustrating a conventional example.

[Explanation of symbols]

 Reference Signs List 30 caliper 30a, 30b arm 32 wheel 32a disk 33a, 33b pad 34 piston 35 cylinder 37 liner 38 receiving hole 39 spherical contact 39a convex 39b concave 40 head

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J058 AA42 AA48 AA53 AA58 AA69 AA73 AA77 AA83 AA87 BA51 CA45 CC03 CC35 CC78 FA21

Claims (4)

[Claims] 1. A disk comprising: a disk rotating integrally with a wheel; a caliper mounted on a chassis; a pad mounted on the caliper via a support mechanism in a state facing the disk; and means for pressing the pad against the disk. In the brake device, the pad supporting mechanism includes a receiving hole provided to extend in a direction in which the pad is pressed against the caliper, and a supporting member partially accommodated in the hole. While providing a gap between the inner periphery of the hole and the support member coaxial with the support member and allowing the support member to swing within a predetermined range around a fulcrum imagined on the pad side,
A disk brake device, wherein a spherical contact portion having a radius of curvature centered on a swing fulcrum of the support member is set between a bottom surface of the accommodation hole and a rear end of the support member. The means for pressing the pad against the disk includes a piston for driving the pad in the pressing direction when supplied with fluid pressure, while the piston forms a support member so as to function as a support mechanism for the pad. The disk brake device according to claim 1, further comprising: a liner portion that forms a receiving hole; and a cylinder that supports the liner portion on the caliper so as to slide freely in a direction in which the pad is pressed. 3. The disk brake device according to claim 1, wherein the pivot point of the support member is set at a position that is half of a pad allowance. 4. The method according to claim 1, wherein the spherical contact portion includes a concave portion on the side of the receiving hole and a convex portion on the supporting member side, and the concave portion is formed by fitting the concave portion into the receiving hole. The disc brake device as described.