JPH09264359A - Brake shoe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease abnormal sound in braking and to prevent decrease of brake capacity by providing cutout parts on the bottom surface side of a lining along the edges of the lining, forming the width of each cutout part in the specified range of the total width of the lining, and forming the height of each cutout part in the specified range of the total height of the lining. SOLUTION: The bottom surface of a lining 2 is bonded to the front surface of a shoe rim 1, and cutout parts 3 extending along the edges in the longitudinal direction of the shoe rim 1 are formed on the bottom surface side. The width of each cutout part 3 is formed in the range of 5 to 15% of the total width of the lining 2, and the height of each cutout part 3 is formed in the range of 3 to 10% of the lining 2. When a brake mechanism is operated, the lining 2 is pressed to a brake drum, braking force is generated, the strength on both ends in the width direction are weakened by the cutout parts 3, and therefore, all parts on the front surface of the lining 2 are made to have the same surface pressure, and the lining is not strongly pressed by the brake drum. Therefore, the abnormal sound decreasing effect can be maintained for a long period.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a brake shoe used in a brake device.

[0002]

2. Description of the Related Art As is well known, in a drum brake device, noise may occur during braking. This abnormal noise is caused by the vibration of the brake shoes due to the friction of the brakes, and the types thereof are roughly classified into a relatively low frequency grone and a high frequency squeal.

Of these, the squeal is a so-called "key" sound, which is offensive to the ears, so that measures have been taken to reduce it. For example, the actual exploitation 57-13
No. 0 has the measures as shown in FIG.

FIG. 5 shows a brake shoe in which a lining 2 is bonded to the surface of a curved shoe rim 1,
Recesses 4 are formed on both end surfaces of the lining 2 in the width direction. A shoe web 1a is integrally formed on the shoe rim 1 at right angles thereto.

A brake drum (not shown) is provided around the lining 2 so that the brake shoe is expanded by the action of a wheel cylinder (not shown) so that the lining 2 is pressed against the brake drum. Has become.

As described above, the formation of the recesses 4 on the surfaces of both end portions in the width direction of the lining 2 is a device which pays attention to the fact that this portion is strongly pressed against the drum and a squeal often occurs. A certain noise reduction effect is recognized by deleting the part where the squeal occurs.

As an example of forming the concave portion, as shown in FIG. 5, there is a method of cutting the corner portion into a band shape, or a method of forming an inclined portion by cutting diagonally (chamfer processing).

[0008]

However, in the above-mentioned conventional device, both end portions in the width direction of the lining 2 do not come into contact with the brake drum during braking. This is the same as using a narrow lining, which reduces the contact area with the brake drum.
Brake capacity is reduced.

Further, there is also a problem that when the lining 2 is worn out, the recesses are also eliminated and the noise preventing effect cannot be maintained. The present invention has been made in view of the above matters,
A technical issue is to provide a brake shoe that can prevent abnormal noise during braking and that does not reduce the brake capacity.

Further, it is a technical object to provide a brake shoe capable of maintaining the noise reduction effect even if the lining is worn out.

[0011]

In order to solve the above technical problems, the present invention provides a lining 2 on the surface of a shoe rim 1.
The brake shoe with the bottom surface fixed was configured as follows.

That is, in the structure of claim 1, a notch 3 is provided along the edge of the lining 2 on the bottom surface side of the lining 2, and the width of the notch 3 is 5% of the total width of the lining 2. The height of the notch 3 is 3% to 10% of the total height of the lining 2 while being formed to be 15%. [Shoe rim 1] The shoe rim 1 is made of iron, aluminum alloy, or the like and is curved in a substantially semicircular shape, and is arranged inside the brake drum. [Lining 2] Lining 2 is an inorganic fiber other than asbestos,
Thermosetting resin, such as phenolic resin, with organic friction modifier, solid lubricant, metal powder, filler, etc. added with one or more of organic fiber such as aramid fiber and metal fiber such as copper fiber as a base material. And is pressed against the inside of the brake drum. The lining 2 may be firmly adhered to the shoe rim 1 or may be fixed by other fixing means. [Notch 3] The notch 3 is on the bottom surface side of the lining 2, that is,
It is formed on the joint surface with the shoe rim 1. This may be formed in advance at the stage of forming the lining 2, or the lining 2 having the same shape as the conventional one may be adhered to the shoe rim 1 and then cut by a cutter. In addition,
The shape may be a square cross section or a semicircular corner.

The notch 3 is preferably provided along both sides in the longitudinal direction of the lining 2 (along both sides in the longitudinal direction of the shoe rim 1), but is provided over the entire circumference of the lining 2. Is also possible.

In the above structure, when the lining 2 is pressed against the brake drum, the strength of both ends of the lining 2 in the width direction is weakened by the notches 3, so that both ends are not strongly pressed against the brake drum. . Therefore, the same pressure contact force is applied to the surface of the lining 2 at any part, and the occurrence of squeal, which is mainly caused by the vibration at both ends of the lining 2 in the width direction, is suppressed.

On the other hand, since the contact area of the lining 2 with the brake drum is the same as that of the normal lining (the area equivalent to the width of the shoe rim 1), the brake capacity is not reduced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a partial perspective view of a brake shoe. The shoe rim 1 is curved according to the inner diameter of a brake drum (not shown), and the shoe web 1a is integrally attached to the center of the shoe rim 1. As a result, the shoe rim 1 and the shoe web 1a are integrated in a T-shaped cross section. The shoe rim 1 and the shoe web 1a are made of iron or aluminum alloy. The bottom surface of the lining 2 is adhered to the surface of the shoe rim 1.

As shown in FIG. 2, a notch 3 is formed on the bottom surface side (base portion) of the lining 2 along the longitudinal edge of the shoe rim 1. This notch 3 has a width W
Is 5% to 15% of the total width of lining 2,
Further, the height H of the notch 3 is 3% of the total height of the lining 2.
Or 10%. Specifically, for example, when the lining 2 has a total width of 145 mm and a total height of 10 mm, the notch 3
The width W can be set to 15 mm and the height H can be set to 0.5 mm. The drum diameter in this case is 320 mm.

The notch 3 may be formed in advance at the stage of forming the lining 2, or may have the same shape as the conventional one (notch 3
The lining 2 (which has not been formed) may be attached to the shoe rim 1 and then cut off with a cutter.

In the first embodiment shown in FIG. 2, the notch 3 has a semicircular cross section at the inner part of the notch 3. Also,
In the second mode shown in FIG. 3, the inner portion of the cutout portion 3 is cut into a semicircular shape, and the remaining portion 5 of the lining 2 is left on the bonding surface with the shoe rim 1. Further, in the third aspect shown in FIG. 4, the cutout portion 3 has a rectangular cross section.

In the second embodiment shown in FIG. 3, while sufficiently securing the adhesive surface between the lining 2 and the shoe rim 1,
The width W of the notch 3 can be widened. Therefore, it is possible to obtain the effect of sufficiently lowering the strength of both end portions of the lining 2 in the width direction without lowering the adhesive strength between the lining 2 and the shoe rim 1 and lowering the pressure contact property with the brake drum.

The operation of this embodiment having the above-described structure will be described. When a brake mechanism (not shown) is activated,
The lining 2 is pressed against the brake drum to generate a braking force. At this time, since the strength of both widthwise end portions of the lining 2 is weakened by the notch portion 3, any surface portion of the lining 2 has the same surface pressure. Therefore, a part of the lining 2 is not strongly pressed by the brake drum, and squeal can be suppressed.

On the other hand, since the width of the surface of the lining 2 is the same as that of a normal lining and the surface of the lining 2 is not cut off, stepped wear is less likely to occur on the inner surface of the brake drum.

Further, since the contact area between the brake drum and the lining 2 is not reduced as in the conventional case, the brake capacity is not reduced.

[0024]

According to the present invention, since the strength of both ends of the lining in the width direction is weakened by the notches, a part of the lining is not strongly pressed against the brake drum during braking. Therefore, it is possible to suppress the occurrence of squeal, which is thought to occur mainly at both ends of the lining in the width direction.

Furthermore, since the width of the lining surface is the same as the width of a normal lining, there is no fear that the brake capacity will decrease. Further, even if the lining surface is worn away, the cutout portion is not affected, and the noise reduction effect can be maintained for a long time.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a first aspect according to the exemplary embodiment of the present invention.

FIG. 3 is a cross-sectional view of a second aspect in the exemplary embodiment of the present invention.

FIG. 4 is a sectional view of a third aspect according to the exemplary embodiment of the present invention.

FIG. 5 is a sectional view showing a conventional brake shoe.

[Explanation of symbols]

 1 ・ ・ Shoe rim 1a ・ ・ Shoe web 2 ・ ・ Lining 3 ・ ・ Notched part 5 ・ ・ Remaining part

Claims (1)

[Claims] 1. A brake shoe having a bottom surface of a lining fixed to the surface of a shoe rim, wherein a cutout portion is provided on the bottom surface side of the lining along the edge portion of the lining, and the width of the cutout portion is 5 times the total width of the lining. % To 15%, and the height of the notch is formed to 3% to 10% of the total height of the lining.