JPS5940025A - Shoe for brake drum - Google Patents

Abstract

PURPOSE:To prevent the noise due to the vibration from occurring by fixing an overlap on a part of the shoe, forming the loop of the vibration when the shoe vibrates at the time of braking. CONSTITUTION:The back metal 9 is fixed to the outer peripheral surface of a substantially crescent-shaped web 3, and further an overlap 10 is fixed to both side surfaces of the central part of the web 3 of the shoe 2 for the drum brake applied at the outer peripheral surface of the back metal 9 with a lining 4. Therefore, during the braking operation even when the shoe 2 is going to vibrate at a point X as a node in accordance with the friction between the inner peripheral surface of the drum and the outer peripheral surface of the lining 4, since the inertial mass of the central part of the shoe which becomes the loop of the vibration, is large, the vibration is difficult to be produced, and the shoe 2 vibrates largely. Thus, no noise is generated.

Description

Detailed Description of the Invention (Technical Field) This invention relates to an improvement in a drum brake shoe that is incorporated into a drum brake used for braking an automobile and presses a lining against the inner peripheral surface of a drum that rotates together with a wheel during At1 braking. BACKGROUND ART) A drum brake used for braking an automobile has a pair of left and right shoes 2.2 inside a drum 1 that rotates together with the wheels, as shown in FIG. 1, for example. The piston rod 6.6 of the hydraulic cylinder 5, which is in contact with one end of the web 3.3, is made to protrude left and right, and both shoes 2.
2 is rotated around an anchor 8 fixed to the opposite end of the hydraulic cylinder 5 of the back plate 7 and pushed out by an external force, and the lining 4.4 attached to the outer periphery of the shoe 2.2 is pushed out inside the drum 1. It is configured so that it can push strongly against the circumferential surface and improve braking.

By the way, the shoe 2 that is assembled and broken in the drum brake that is constructed and operated as described above vibrates finely due to the friction between the inner circumferential surface of the drum 1 and the outer circumferential surface of the lining 4 during braking, producing a noise called squeal. will occur.

(Object of the present invention) In order to prevent the above-mentioned noise generation, the present invention provides a drum brake shoe that does not easily vibrate even when the outer circumferential surface of the lining rubs against the inner circumferential surface of the drum during braking. (Structure of the present invention) The drum brake shoe of the present invention suppresses the L vibration by fixing a weight to the antinode of the vibration when the shoe vibrates during braking. It is.

That is, according to the research of the present inventor, when the drum brake shoes vibrate during braking, as shown in FIG. As shown in the exaggerated broken line in the same figure, shoe 2 is
All one vibrates. For this reason, the central portion and both end portions of shoe 2 become the antinodes of vibration, and the amplitude is the largest when this shoe 2.2 vibrates. Therefore, if a weight is provided at the center or both ends of the shoe 2, which is the antinode of this vibration, and the vibration of this part is suppressed, the braking of the shoe 2 as a whole will be suppressed, and the generation of noise during braking will be prevented. be done.

(Embodiments of the present invention) Next, the present invention will be explained in more detail while explaining embodiments shown in the drawings.

3-4 show a first embodiment of the invention. A backing metal 9 is fixed to the outer peripheral surface of a substantially crescent-shaped web 3, and a lining 4 is attached to the outer peripheral surface of this backing metal 9.A drum brake shoe 2 has weights 1 on both sides of the central part of the web 3.
0.10 is fixed. In this way, put 1 weight in the center.
Since the value of 0.10 is fixed, even if the shoe 2 attempts to vibrate around the aforementioned point Since the inertial mass of the shoe 2 is large, it is difficult to generate vibrations, and the shoe 2 does not vibrate greatly and generate unpleasant noise) 0 In addition, in order to suppress the vibration of the shoe 2, it is necessary to Instead of fixing the weight to the center of the web 3, as shown by the chain line in FIG.
A similar effect can be obtained by fixing weights 10.1.0 to both ends of the web 3. Furthermore, if the weight 10 is fixed to both the center and both ends of the web 3, the noise prevention effect will be even more certain. However, as shown in FIGS. 5 and 6, in the case of a drum brake nut made by integrally casting the web 3 and the backing metal 9, the web 3 and the backing metal 9 are fixed together.
The weight 10 may be integrally cast when casting.

(Effects of the present invention) As described below, the nodram brake shoe of the present invention has a simple structure that suppresses the vibration of the shoe during braking, and the noise accompanying the vibration of the shoe is either inaudible or inaudible. However, it can be reduced to such an extent that it does not bother Kfx at all.

[Brief explanation of drawings]

Fig. 1 is a side view of the drum brake, Fig. 2 is a side view of the platen knee for explaining the vibration state, Figs. 3 and 4 show the first embodiment of the present invention, and Fig. 3 is a side view. Fig. 4 is a sectional view taken along the line A-A in Fig. 3, Figs. 5 and 6 show the second embodiment, Fig. 5 is a side view, and Fig. 6 is a 1-1
3-B sectional view 0 1 Ni drum, 2: Shoe, 3: Web, 4 Ni lining, 5: Hydraulic cylinder, 6: Piston rod, 7: Back plate, 8:
Anchor, 9: Back metal, 10: Weight 0

Claims (1)

[Claims] In a drum brake shoe that has a lining (4) on the outer periphery of a roughly crescent-shaped web (3), a weight (river) is fixed at a position away from the vibration node, which is slightly closer to the center from both ends. Shoes for drum brakes that are characterized by: