JPH0412261Y2 - - Google Patents

Description

[Detailed description of the invention] a. Purpose of the invention (industrial application field) The drum brake shoe according to this invention is used by being incorporated into a drum brake used for braking automobiles. This prevents the drum brake shoe from vibrating during braking and causing harsh noise.

(Prior Art) Drum brakes, such as the one shown in FIG. 2, are widely used for braking automobiles.

When braking is performed using such a drum brake, pressure oil is supplied through the oil supply pipe 1 into the foil cylinders 3, 3 fixed to the top and bottom of the back plate 2, and the rods 4, When the pair of left and right shoes 5, 5 are pushed apart by the lever 4, the linings 6, 6 of each shoe 5, 5 are pressed against the inner circumferential surface of the drum 7, which rotates together with the wheels, and braking is performed.

During braking, the lining 6 forming the shoe 5
Due to strong friction between the outer circumferential surface of the drum 7 and the inner circumferential surface of the drum 7, a strong force is applied in the shearing direction between the inner circumferential surface of the lining 6 and the outer circumferential surface of the back metal 8 to which the lining 6 is attached. In order to prevent the lining 6 from peeling off from the back metal 8 due to such force in the shearing direction, the lining 6 and the back metal 8 are connected by a plurality of rivets 9, 9 as shown in FIG. It is widely practiced.

(Problem that the invention attempts to solve) However, as mentioned above, the lining 6 is replaced by the back metal 8.
Conventionally, in a drum brake shoe which is connected and fixed by a plurality of rivets 9, 9,
A harsh noise often occurred during braking.

Possible causes of this noise are:
It is as follows.

That is, it is unavoidable that a fine gap exists partially between the inner circumferential surface of the lining 6 and the outer circumferential surface of the back metal 8, which are connected to each other by the rivets 9, 9. When the surface and the inner circumferential surface of the drum 7 strongly rub against each other, it is thought that this minute gap vibrates in a vibrating manner and generates noise.

JP-A-50-21160 discloses a device in which a layer of plastic adhesive is interposed over the entire surface between the inner peripheral surface of the lining 6 and the outer peripheral surface of the back metal 8. Similarly, if a layer of adhesive is interposed over the entire surface between the inner circumferential surface of the lining 6 and the outer circumferential surface of the back metal 8, the temperature of the shoe 5 will increase due to the frictional heat generated during braking. If this happens, the adhesive layer will change in volume and the rivet 9,
9 becomes loose, which makes it more likely to generate noise.

The drum brake shoe of the present invention eliminates all of the above-mentioned disadvantages.

b. Structure of the invention (Means for solving the problem) The drum brake shoe of the present invention is formed on a web 10 made of a thick metal plate, as shown in FIG. The lining 6 is fixed to the outer circumferential surface of a back metal 8 fixed to a circular arc-shaped support edge, using a plurality of rivets 9.

Furthermore, in the drum brake shoe of the present invention, between the outer circumferential surface of the back metal 8 and the inner circumferential surface of the lining 6, a portion separated from the portion where the plurality of rivets 9, 9 are inserted, A thin rubber adhesive layer 11 is formed.

That is, in order to insert a plurality of rivets 9, 9,
Rubber-based adhesive is applied to the lining 6 and the back metal 8 at positions apart from the small through holes 12 and 13, which have the same number as the rivets 9 and 9, respectively, as shown by the diagonal grid in FIG. By applying a thin layer (approximately 0.1 to 0.2 mm) of rubber adhesive, a layer 11 of rubber adhesive is formed, and after overlapping the lining 6 and back metal 8 with each other via this layer 11, both members 6 and 8 are bonded. They are connected by a plurality of rivets 9,9.

As a rubber adhesive, for example, Hamatite No.A-862-B (trade name) manufactured by Yokohama Rubber Co., Ltd.
However, preferably it can be used.

(Function) The drum brake shoe of the present invention configured as described above is used by being incorporated into a drum brake, as shown in FIG. 2, like the conventional drum brake shoe described above. Even when the outer circumferential surface of the lining 6 and the inner circumferential surface of the drum 7 are strongly rubbed, no harsh noise is generated due to this friction.

The inventor of the present invention incorporated the shoe of the present invention and the conventional shoe into the drum brake of a large 6-ton truck, and determined whether or not noise can be heard from the driver's seat, and if so, how much noise can be heard while driving. According to human ear measurements, when the conventional shoe was installed, almost every time the driver braked, the noise was loud enough to be heard by the driver, and some of the times the noise was so loud that it was quite annoying. On the other hand, when the shoe of the present invention was installed, no noise audible to the driver was generated at all.

This is thought to be because the rubber adhesive layer 11 existing between the inner peripheral surface of the lining 6 and the outer peripheral surface of the back metal 8 prevents vibrations from being transmitted between the two members 6 and 8. .

c. Effects of the invention The drum brake shoe of the present invention is constructed and operates as described above, so it reliably prevents the generation of harsh noises during braking, causing no harm to occupants or nearby pedestrians. There will be no more pleasure.

In addition, in a drum brake shoe in which the lining 6 and the back metal 8 are joined by rivets 9, 9, if the lining 6 becomes worn, only the lining 6 can be replaced and the back metal 8 and web 10 can be reused. However, in the case of the shoe for drum brakes of the present invention, the inner circumferential surface of the lining 6 and the outer circumferential surface of the back metal 8 are only partially adhered, so it is necessary to use an adhesive. Accordingly, it is not particularly difficult to separate the lining 6 and the back metal 8.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing a shoe for a drum brake according to the present invention, FIG. 2 is a front view showing an example of a drum brake, and FIG. 3 is a sectional view of a conventional shoe for a drum brake. 1... Oil supply pipe, 2... Back plate, 3... Foil cylinder, 4... Rod, 5... Shoe, 6... Lining, 7... Drum, 8... Back metal, 9... Rivet, 10... ...Web, 11...Rubber adhesive layer, 12, 13...Small through holes.

Claims (1)

[Scope of utility model registration request] In a drum brake shoe in which a lining is fixed with multiple rivets to the outer circumferential surface of a backing metal fixed to an arc-shaped support edge formed on a web made of a thick metal plate, the outer circumference of the backing metal and the lining are fixed. A shoe for drum brakes characterized by forming a thin layer of rubber-based adhesive between the inner peripheral surface of the drum and the inner circumferential surface of the shoe, leaving an unapplied area.