JPS5922350Y2 - Drum brake anchor device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a fixed anchor device for a drum brake.

Conventionally, this type of device squeezes a part of the anchor on the back plate, installs a relatively thick anchor plate in this part that receives the braking force, and then uses a glue retainer to prevent the brake shoe from floating on the back plate and coming off the anchor. Since it was fixed integrally with the anchor plate, it had the disadvantage of being heavy and increasing manufacturing costs.

Also, a portion of the retainer extends to hold the spring suspended between the brake shoes in place.

In order to eliminate these drawbacks, the present invention provides a fixed anchor device in which the anchor is formed into a square shape with flanges and the anchor plate and retainer are integrated.

Alternatively, in order to hold the spring in place, it is sufficient to extend a portion of the flange, so that it is easy to integrally mold the spring.

Examples thereof will be described in detail below with reference to the drawings.

Fig. 1.2 shows an example of a conventional brake device, in which numeral 1 denotes a brake drum that rotates together with wheels (not shown).

2 is a fixed back plate.

Reference numerals 3 and 4 denote a pair of opposing brake shoes, which have linings 5 and 6 attached to their outer peripheries, and are movably mounted on the back plate 2.

Reference numeral 7 denotes an input generator, which is fixed on the back plate 2 with bolts or the like.

The other part of the back plate 2 is drawn up and the anchor plate 8 and retainer 9 are crimped together with rivets 10.

The retainer 9 has ears 11 and 12 that extend in the longitudinal direction from the anchor plate 8, and a tongue 13 that partially extends in the direction opposite to the brake center.
is held in place.

Numerals 14 and 15 are a large load spring and a small load spring, respectively, which are stretched between the brake shoes 3 and 4 and are always biased in the direction in which the brake shoes 3 and 4 are contracted.

Reference numeral 16 denotes a lining wear adjustment device that abuts against the pair of brake shoes 3 and 4 to prevent the brake shoes 3 and 4 from contracting beyond a certain level.

In the drum brake configured as described above, when the input generating device 7 is activated, the brake shoes 3 and 4 rotate about the abutting portion with the anchor plate 8 as a fulcrum against the large load spring 14, and the linings 5 and 6 are attached to the brake drum 1. Brake this by applying pressure.

Ear portions 11.12 and tongue portions 13 of the retainer 9 are provided to prevent the brake shoes 3.4 and small load springs 15 from separating from the anchor plate 8 due to vibrations or the like during running.

The present invention is one in which the anchor plate 8 and the retainer 9 are integrally molded. 4. To explain with reference to FIG. 5, the opposing upright portions of the fixed anchor formed in the square shape 17 are used as the abutting portions 19, 20 of the brake shoes 3a, 4a, and at least a part of the opposing openings are used as the brake shoes 3a.
, 4a toward the flange 18, and the parts corresponding to the ears 11 and 12 of the conventional example are integrally molded (the figure shows the flange 18 over the entire circumference). The bottom surface of this is fixed to the back play (2a) with rivets (10a).

Therefore, the movement of the brake shoes 3a, 4a toward the opening side of the box-shaped anchor 17 can be reliably maintained by the flange 18.

In FIG. 3, the abutting portions 19, 20 of the fixed anchor against which the brake shoes 3a, 4a abut are shown to be inclined, but it is clear that they may be parallel.

In addition, when the outer diameter of the coil of the small load spring 15a becomes large and there is a risk that it may come off the flange 18 due to vibrations during running, etc., a tongue portion 21 that is an extension of a portion of the flange 18 that contacts the spring 15a is integrally molded. If the spring 15a is held by the tongue portion 21, the movement of the spring 15a toward the opening side of the box-shaped anchor 17 can be reliably restricted.

As mentioned above, the present invention has great practical effects in reducing the number of components, weight, and manufacturing costs by using an integrally molded square-shaped anchor device.

[Brief explanation of drawings]

FIG. 1 is a plan view of a conventional drum brake. FIG. 2 is a sectional view taken along the line II in FIG. Figure 3 is a plan view of the main part of the present invention. FIG. 4 is a sectional view taken along line II-II in FIG. FIG. 5 is a sectional view taken along line III--III in FIG. 3. 1... Brake drum, 2, 2a...
Back plate, 3, 3a, 4, 4a... Brake shoe 7... Input generator, 8...
・Anchor plate, 9...Retainer-111
, 12...Ear part, 13...Tongue part, 17
...Match-shaped anchor, 18...Flange, 21...Tongue.

Claims (1)

[Claims for Utility Model Registration] 1. The upper ends of a pair of opposing brake shoes movably mounted on the back plate abut against an input generating device fixed to the back plate, and the lower ends are similarly mounted on the back plate. In an inwardly expanding drum brake that abuts against an anchor fixed to a brake shoe, the anchor is formed into a box shape, and the opposing upright portion is the abutment surface for the brake shoe, and the opposing opening A fixed anchor device for a drum brake, characterized in that at least a part of the brake shoe extends in the form of a flange toward the brake shoe, and is configured to hold the brake shoe against movement in a direction in which the brake shoe floats up from the back plate. . 2 A part of the opening of the box-shaped anchor is extended toward the spring to form a tongue part integrally, and the spring is held against movement of the spring toward the opening of the box-shaped anchor. A fixed anchor device according to claim 1 of the utility model registration claim, characterized in that: