JPH0550173U - Shoe-hold device for vehicle drum brakes - Google Patents

Abstract

(57) [Summary] [Purpose] To simplify the assembly of the brake shoe with the shoe hold pin and shoe hold spring. [Structure] Drum side piece 6 of shoe hold spring 6
c, a locking portion insertion hole 6d through which the locking portion 5c of the shoe hold pin 5 can be inserted, and a shaft portion 5a of the shoe hold pin 5 through the bending portion, which can be inserted. The pin shaft portion insertion hole 6e in which the portion 5c cannot be inserted is continuously provided in a so-called dharma hole shape.
A concave portion 6g on which the engaging portion 5c of the shoe-hold pin 5 is seated is formed around e.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle drum brake shoe-holding device for holding a brake shoe on a back plate by a shoe-hold pin and a shoe-hold spring.

[0002]

[Prior Art]

 Through the web of the back plate and the brake shoe, the pin locking hole of the shoe hold spring located on the drum side of the web has a locking part that is wider than the pin shaft at the tip of the shoehold pin. For example, a shoe hold device for a vehicle drum brake, which inserts the locking portion on the side surface of the drum of the shoe-hold spring and elastically holds the brake shoe on the back plate, is disclosed in, for example, Shokai 64-36735. It is presented in the official gazette.

[0003]

[Problems to be solved by the device]

 However, in the conventional shoehold device, the locking portion wider than the shaft portion of the shoehold pin protruding from the pin insertion hole of the web has a rectangular pin locking hole formed in the shoehold spring. The shoe-holding spring is mounted by inserting the shoe-holding spring into the shoe-holding pin by rotating the engaging portion of the shoe-holding pin protruding from the pin engaging hole.

Therefore, it cannot be inserted unless the shoe hold pin is rotated and accurately positioned in the pin engagement hole of the shoe hold spring, and the shoe hold pin inserted in the pin engagement hole of the shoe hold spring is used. Since the shoe hold pin is fixed by rotating the pin 90 degrees about its axis, the assembly efficiency is poor. Especially in the automatic assembly machine, the movement of the shoe hold pin in the axial direction and the pin rotation Since the structure moves in the directional direction, the structure is complicated and the cost is disadvantageous.

Further, since the head portion of the shoe-hold pin is rotated while being pressed against the pin insertion hole, the plating of the shoe-hold pin is peeled off at that portion, which makes the shoe-hold pin less prone to rusting and other problems. is there.

The present invention has been made in view of the above circumstances, and an object of the present invention is to simplify the assembling of the shoe-hold pin, and thus to simplify the structure of the automatic assembling machine. An object of the present invention is to provide a shoe-hold device for a vehicle drum brake which has improved efficiency and excellent durability.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention penetrates the back plate and the web of the brake shoe, and inserts the tip of the shoe hold pin into the pin retaining hole of the shoe hold spring arranged on the drum side of the web. A locking portion formed wider than the pin shaft portion is inserted into this, and the locking portion is locked to the drum side surface of the shoe hold spring to elastically hold the brake shoe on the back plate. -In the hold device, the pin locking hole of the shoehold spring is provided with a locking part insertion hole through which the locking part can be inserted, and a locking part continuous with the locking part insertion hole. It is characterized in that it is formed with an impossible pin shaft portion insertion hole.

[0008]

[Action]

 According to this structure, the shoehold pin inserted through the pin insertion hole of the back plate and the pin insertion hole formed in the web of the brake shoe is tilted, and the locking portion formed at the front end is compressed. Insert the shoe hold spring into the engagement hole, and then put the shoehold pin upright and insert its shaft into the pin shaft insertion hole to release the compression of the shoe hold spring. Then, the locking part is locked to the side of the shoe hold spring drum, and the brake shoe is elastically held on the back plate.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

1 to 5 show a first embodiment of the present invention, in which a drum brake 1 includes a pair of left and right arch-shaped members on a drum (not shown) side of a back plate 2 fixed to a vehicle body. Brake shoes 3 and 4 consisting of a leading shoe and a trailing shoe are arranged facing each other, and the brake shoes 3 and 4 are elastically held by shoe hold pins 5 and shoe hold springs 6.

The brake shoes 3, 4 have linings 3 b, 4 b fixed to the rims 3 a, 4 a, and the ends 3 d, 4 d of the webs 3 c, 4 c are fixed to the upper part of the back plate 2 and are the pistons of the wheel cylinder 7. 8 and 9 and the other ends 3e and 4e of the back plate 2 are brought into contact with the anchor 10 fixed to the lower part of the back plate 2 and the pistons 8 and 9 of the wheel cylinder 7 are projected to expand the lining. Sliding 3b and 4b on the drum provides braking action.

Further, between the brake shoes 3 and 4, a strut for restricting the backward limit of the brake shoes 3, 4 and transmitting the rotation of the parking lever 11 pivotally supported by the brake shoes 4 to the brake shoes 3. 12, the return springs 13 and 14 of the brake shoes 3 and 4 are hooked on the struts 12.

The shoe-hold pin 5 has a head portion 5b having a diameter larger than that of the shaft portion 5a and a locking portion 5c formed at both ends of the shaft portion 5a. It is bent in a letter shape and is arranged on the drum side of the webs 3c and 4c.

On the web side piece 6a of the shoe hold spring 6, a pin insertion hole 6b having a diameter considerably larger than that of the locking portion 5c of the shoe hold pin 5 is formed, and the drum side piece 6c has an end portion. On the side, a locking portion insertion hole 6d through which the locking portion 5c of the shoe hold pin 5 can be inserted is provided. On the bent side, the shaft portion 5a of the shoe hold pin 5 can be inserted and the locking portion 5c is inserted. The pin shaft insertion holes 6e that cannot be attached are continuously provided in a so-called Dharma hole shape. Further, the engagement parts 5c of the shoe hold pins 5 are seated around the pin shaft insertion holes 6e on the drum side surface 6f. A concave portion 6g is formed.

The assembling of the one brake shoe 4 by the shoe hold pin 5 and the shoe hold spring 6 thus configured will be described with reference to FIGS. 2 and 3.

First, as shown in FIG. 2, the engaging portion 5 c at the tip of the shoe hold pin 5 is inserted from the outside of the back plate 2 into the pin insertion hole 2 a formed in the back plate 2 and the web 4 c of the brake shoe 4. The pin insertion hole 4f formed is slanted and inserted, and the compressed spring spring 6 is inserted from the pin insertion hole 6a on the web side to the engagement hole 6b on the drum side.

Next, as shown in FIG. 3, the shoe hold pin 5 is erected, the shaft portion 5a is inserted into the pin shaft portion insertion hole 6c, the compressed state of the shoe hold spring 6 is released, and the shoe hold pin 6 is released. The locking portion 5c of the hold pin 5 is seated in the recess 6e formed in the drum side surface 6d of the pin shaft insertion hole 6c.

As a result, the shoe hold pin 5 engages the head portion 5b with the outer periphery of the insertion hole 2a of the back plate 2 and engages the engagement portion 5c with the drum side surface 6d of the shoe hold spring 6. Hold the brake shoe 4. Also, the other brake shoe 3 is similarly held.

Therefore, by moving the shoe hold pin 5 in an oblique direction to make it stand upright, the brake shoes 3 and 4 can be elastically held without rotating, so that the shoe can be assembled very easily and the assembling efficiency can be improved. Very good.

Further, even when the automatic assembling machine is used for assembling, the automatic assembling machine does not need a rotation operation mechanism, so that the structure of the automatic assembling machine can be simplified and the shoe hold pin 5 is not rotated. Therefore, the peeling of the plating due to the sliding contact between the head portion 5b of the shoe hold pin 5 and the back plate 2 is eliminated, and the durability of the shoe hold pin 5 is improved.

6 to 10 show a second embodiment of the present invention, in which the shroud pin 20 has a locking portion 20b wider than the shaft portion 20a with the tip of the shaft portion 20a being flat. The shoe hold spring 21 has a substantially triangular engaging portion insertion hole 21b into which the engaging portion 20b can be inserted in the drum side piece 21a, and an engaging portion 20b that is continuously provided in the engaging portion insertion hole 21b. And a rectangular pin shaft insertion hole 21c that cannot be rotated are formed, and the end side 21d is further bent from the pin shaft insertion hole 21c to the drum side.

The locking portion insertion hole 21b has a narrow width on the pin shaft portion insertion hole 21c side and widens toward the end side so that the locking portion 20b can be inserted into the end side. There is.

Assembling of one of the brake shoes 4 by the shoe-hold pin 20 and the shoe-hold spring 21 of this embodiment is substantially the same as that of the above-mentioned embodiment, and as shown in FIG. The locking portion 20b is parallel to the end portion side of the locking portion insertion hole 21b of the shoe hold spring 21 and is inserted in an oblique direction. When the compressed state is released, since the urging force of the shoe hold spring 21 and the end portion side 21d of the shoe hold spring 21 are bent toward the drum side, the shaft portion 20a of the shoe hold pin 20 is shoe held. The spring 21 is moved to the pin shaft insertion hole 21c, and the engagement portion 20b of the shoehold pin 20 is moved to the shoe hold spring. The brake shoe 4 is elastically held by being locked to the drum side surface 21e of 21.

Therefore, as in the above-described embodiment, it is possible to make the back plate 2 hold the brake shoes 3 and 4 very easily without rotating the shoe-hold pin 21.

In particular, since the engaging portion insertion hole 21b of the shoe hold spring 21 has a triangular shape having a hypotenuse that narrows toward the pin shaft portion inserting hole 21c, the engaging portion insertion hole 21b in the inclined state is It is said that the shaft portion 20a of the shoehold pin 20 moves very smoothly to the pin shaft portion insertion hole 21c along the mutually opposite oblique sides of the triangle when the shoehold pin 20 inserted is erected. Have advantages.

[0026]

[Effect of the device]

 As described above, according to the present invention, the pin locking hole of the shoehold spring is provided with the locking part insertion hole through which the tip locking part of the suspension pin can be inserted, and the locking part continuous with this. Of the pin shank that cannot be inserted through the back shaft and the pin insertion hole formed in the web of the brake shoe. Insert the locking part formed on the shaft into the locking part insertion hole formed in the compressed shoe hold spring, then erect the shoehold pin and insert the shaft part into the pin shaft part insertion hole. Wear it to release the compression of the shoe-hold spring and lock the locking part to the drum side of the shoe-hold spring to elastically hold the brake shoe on the back plate. Shoe hold Accurate positioning that matches the pin locking hole of the pulling is not required, and it is possible to lock the shoehold pin inserted in the pin locking hole without rotating it. This simplifies assembly, improves assembly efficiency, simplifies the structure of the automatic assembly machine, and improves durability of the shoe-hold pin.

[Brief description of drawings]

FIG. 1 is a perspective view showing a shoe hold spring according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an assembled state of shoe hold pins.

FIG. 3 is a cross-sectional view showing a completed state of assembling the shoe hold pin.

FIG. 4 is a plan view of the drum brake according to the first embodiment of the present invention.

5 is a sectional view taken along line VV of FIG.

FIG. 6 is a perspective view showing a shoe hold spring according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view showing an assembled state of shoe hold pins.

FIG. 8 is a cross-sectional view showing a completed state of assembling the shoe hold pin.

9 is a view on arrow IX-IX in FIG.

FIG. 10 is a view on arrow XX in FIG.

[Explanation of symbols]

1 ... Drum brake, 2 ... Back plate, 3 ... Brake shoe, 4 ... Brake shoe, 3c ... Web, 4c ...
Web, 5,20 ... Shoe hold pin, 5c, 21b
… Locking part, 6, 21… Shoe hold spring, 6
d, 21b ... Locking portion insertion hole, 6e, 21c ... Pin shaft insertion hole, 6f, 21e ... Drum side surface

Claims (1)

[Scope of utility model registration request] 1. A pin holding hole of a shoe hold spring arranged on the drum side of the web that penetrates through the web of the back plate and the brake shoe, and is formed wider at the tip of the shoehold pin than at the pin shaft portion. Insert the locked part,
In a shoe hold device for a vehicle drum brake, wherein the locking portion is locked to a drum side surface of a shoe hold spring to elastically hold the brake shoe on a back plate,
The pin locking hole of the shoehold spring has a locking part insertion hole through which the locking part can be inserted, and a pin shaft part insertion hole through which the locking part continuous with the locking part insertion hole cannot be inserted. A shoe-hold device for a vehicle drum brake, characterized by being formed with.