JPS6330827Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a shoe hold-down device for a drum brake, and more particularly to a shoe hold-down device that can be easily attached to and removed from a bucking plate and shoe.

Prior Art Conventionally, pin-type devices have often been used as shun hold down devices for drum brakes. For example, in the hold down device 2 illustrated in FIG. 1, the hold down pin 4 has a rod shape,
Both ends are provided with first and second heads 6 and 8, respectively, and are engaged with the bucking plate 10 at the first head 6, passing through holes in the bucking plate 10 and the shew web 12, and further being compressed. After passing through the two cups 16 with the coil spring 14 in between, the upper cup 1 in the figure is inserted into the second head 8.
6. The second head 8 is formed flat in the vertical direction (axial direction), and the upper cup 16 has an elongated hole 18 through which the flat second head can pass, and a groove 19 perpendicular to the elongated hole 18. is provided.

Problems to be Solved by the Invention However, the hold-down device 2 is assembled as shown in FIG. 4 after inserting the hold-down pin 4 into the upper cup 16 as shown in FIGS. This is done by rotating the cup 16 90 degrees and engaging the second head 8 and the groove 19 as shown in FIG. A rotational operation is essential, and there is a risk that assembly may become uncertain due to half-assembly or the like due to excessive or insufficient rotation.

On the other hand, the center part of the cup is cut open to form a plurality of claws that protrude at a predetermined angle, and the head of the hold-down pin is pushed in while each claw is elastically deformed. If the configuration is such that the tip of each pawl returns to its original position after passing between the pawls, preventing the head of the pin from coming off, it will be possible to prevent the rotational operation as described above when assembling the show hold down device. This eliminates the need to assemble the device due to insufficient rotation.

However, such a hold-down device still has problems to be solved.
In other words, the head of the pin is engaged with the cup in a state where it is reliably prevented from coming off, and the engagement between the head of the pin and the pawl of the cup can be achieved by rotating the pin or the cup as in the conventional method. Therefore, when it is necessary to release the engagement between the cup and the pin in order to remove the shoe assembly from the bucking plate for repairs etc.,
The work is relatively troublesome and difficult.

Means for Solving the Problems The present invention was made against the background of the above-mentioned circumstances, and its gist is that in the above-mentioned shew hold down device, the engaging member is made of a spring plate material. By providing the engagement member with a pair of claws whose tips are opposed to each other with a certain gap in between and whose tips are farther away from the shew web, the second head of the hold down pin can be held from the shew web side. Passage is allowed by elastic deformation in the direction in which the gap between the tips of the claws opens, but passage in the opposite direction is not allowed. A pair of notches are provided, each extending in a direction perpendicular to the direction toward the outer circumferential side of the engaging member.

Function and Effect of the Invention With this method, when assembling the drum brake shoe assembly, the second head of the hold-down pin can be simply passed through against the elastic force of the pair of pawls, and the hold-down pin can be easily removed. Since the engaging member can be easily engaged, there is no need for the conventional rotation operation, which not only simplifies the assembly work and reduces work time, but also eliminates the need for excessive rotation as in the conventional method. This completely eliminates the possibility that the assembly will be uncertain due to half-finishing or the like due to shortages.

Furthermore, since the engaging member is provided with a pair of notches that extend toward the outer circumference from between the pair of claws, the engagement between the engaging member and the hold-down pin is released in order to remove the shoe assembly, etc. If necessary, the engaging member can be bent relatively easily along the notch, so that the tips of the pair of claws can be separated from each other and engaged with the head of the hold-down pin. The engagement of the member with the claw can be easily released.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

6 and 7, 32 and 34 are a pair of shoe assemblies in the drum brake 30, one end of which is attached to a return spring 36.
The other end is brought into contact with the anchor block 42 by the urging force of a retainer spring 40.

Wheel cylinder 3 of shoe assembly 32
A parking lever 46 and an adjustment lever 48 are installed in the hole near the adjustment lever 4.
The parking lever 46 is pivotally mounted between the parking lever 8 and the show web 50 so as to be sandwiched therebetween.
The adjustment lever 48 is biased toward the rim by a tension spring 52, and is engaged with the parking lever 46 by a claw portion 54 at the end.

The parking lever 46 and a shoot web 50 to which the parking lever 46 is pivotally connected.
A strut 56 is stretched between the sheath web 51 of the shew assembly 34 and the shew web 51 of the other shew assembly 34.

A hold-down device 62 for preventing the shoe assemblies 32, 34 from floating is shown in FIG. head 6
6 and 68 respectively, the first head 66 is engaged with the bucking plate 44, and the second head 68 passes through holes in the bucking plate 44 and the shew webs 50 and 51, and further includes a compression coil. It passes through two upper and lower disk-shaped cups 72 and 74 with a spring 70 in between, and is engaged with the cup 72 (an engaging member). This second head 68
is spherical, and the lower cup 74 is the second head 68
It has a circular hole through which the upper cup 7 can pass.
2 is provided with means for engaging with the second head 68.

That is, the upper cup 72 is made of an elastic material such as a spring steel plate, and is provided with a pair of claws 76, 76 whose tips are opposed to each other, as shown in FIGS. 9 and 10. The tips of the claws 76 are opposed to each other at a constant interval smaller than the diameter of the second head 68, and the tips are bent upward in FIG.
It is formed to move away from the Therefore, it is possible for the second head 68 of the hold-down pin 64 to pass from the shew web 50 or 51 side by elastic deformation in the direction in which the tip gap of the claw 76 opens, but it is possible to pass the second head 68 of the hold-down pin 64 from the shew web 50 or 51 side by elastic deformation in the direction in which the tip gap of the claw 76 opens. It's impossible. That is, when the second head 68 is inserted as shown in FIGS. 11 and 12, the claw 76 is curved, and after the second head 68 passes, the claw 76 is curved at the bottom of the spherical shape as shown in FIG. In the engaged state, movement in the opposite direction is prevented. Therefore, the hold-down device 62 is engaged in the state shown in FIG. This will prevent it from rising.

In addition, as shown in FIGS. 9 and 10, the cup 72 has an outer circumferential surface that extends from between the pair of claws 76, 76 in a direction perpendicular to the opposing direction of the claws 76, 76. A pair of notches 77, 77 each extending toward the side over a predetermined length are formed with a predetermined width. The engagement operation between the cup 72 and the second head 68 of the hold-down pin 64 is performed by holding the cup 72 in a state in which the upper end of the compression coil spring 70 is in contact with the outer peripheral edge of the cup 72 over the entire circumference. It is done by pressing, so
By forming the notches 77, 77, there is no risk that the strength of the cup 72 will be impaired during engagement.

As mentioned above, in this embodiment, when assembling the drum brake shoe assemblies 32 and 34, there is no need to rotate the hold-down pin or cup as in the conventional case, and the compression coil spring 70 and cup are simply rotated. Since the engagement is completed simply by pressing the cup 72 against the second head 68 against the elastic force of the claw 76 of 72, the assembly work is simplified, and not only can the work time be shortened, but also the conventional This completely eliminates the possibility of assembly being uncertain due to half-assembly or the like due to excessive or insufficient rotation.

In addition, for repairs etc., the assembly 3
If it is necessary to remove parts 2, 34, etc.,
As shown in Figure 4, the cup 72 is cut out 77, 77.
Both outer ends 78, 7 of the claws 76, 76
8 can be relatively easily bent toward each other on the side opposite to the claws 76, 76, thereby widening the gap between the claws 76, 76, so that the second head 68 can be easily removed from the cup 72. can be done.

Although the holes in the shew webs 50 and 51 through which the second heads 68 are inserted are round holes, the present invention is not limited to this in any way, and they may be cut outs.

Further, it is preferable that the tip of the claw 76 has an arc along a spherical surface, but it may also be a V-shape with a concave center or a straight line.

Also, the second head 68 of the hold down pin 64
Although the shape is assumed to be spherical, it is also possible to have a truncated cone shape.

In addition, various changes may be made to the present invention without departing from the gist thereof.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional hold-down device and its surroundings, and FIGS. 2 to 5 are perspective views of essential parts showing the engagement operation between the cup and the hold-down pin. Fig. 6 is a front view of a drum brake equipped with an embodiment of the present invention, Fig. 7 is a cross-sectional view of Fig. 6, Fig. 8 is a cross-sectional view of Fig. 6, and Fig. 9 is an upper view of the drum brake. Cup 7
2, FIG. 10 is a sectional view taken from FIG.
FIG. 14 is a cross section showing the operation of releasing the engagement. 30: Drum brake, 44: Bucking plate, 50, 51: Show web, 62: Hold down device, 64: Hold down pin, 6
6: First head, 68: Second head, 70: Compression coil spring, 72: Cup (engaging member), 7
6: Claw, 77: Notch.

Claims (1)

[Claims for Utility Model Registration] It is rod-shaped and has first and second heads at both ends, the first head is engaged with the bucking plate of the drum brake, and the second head side is a shew web. a hold-down pin that passes through a hole or notch and projects to the opposite side of the bucking plate of the show web; a disc-shaped engagement member that engages with the second head of the hold-down pin; A shew hold-down device including: a coil spring interposed between the engaging member and the shew web and generating an elastic force in a direction to separate the two from each other, wherein the engaging member is made of a spring plate material; By providing a pair of claws on the engagement member, the tips of which are opposed to each other with a certain gap in between, and whose tips are farther away from the shew web, the passage of the second head of the hold-down pin from the shew web side is prevented. Allows elastic deformation in the direction in which the gap at the tip of the claw opens, but does not allow passage in the opposite direction.
The engaging member is provided with a pair of notches extending from between the pair of claws in a direction perpendicular to the opposing direction of the claws and toward the outer circumference of the engaging member. Drum brake shhold down device.