JPH04138134U - drum brake - Google Patents

Abstract

(57) [Summary] [Purpose] To improve assembly work efficiency by assembling a cable to a brake shoe operating lever without pulling out the brake shoe operating lever. [Configuration] The brake shoe operating lever 11 has a mounting groove 19 that opens on the back plate 1 side and allows the cable 12 to be inserted.
and a protrusion 18 that locks the caulking ball 17 at one end 18a.
A convex portion 21 for guiding the caulking ball 17 to the one side end 18a is provided in a portion of the back plate 1 facing a portion near the one side end 18a on the opening 20 side of the mounting groove 19. As the caulking ball 17 is guided to the one side end 18a by the convex portion 21,
Without pulling out the brake shoe operating lever 11, the caulking ball 17 is locked to the one end 18a, and the cable 12 is inserted into the mounting groove 19 and assembled. Work efficiency can be improved by eliminating the need to pull out the brake shoe operating lever 11.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a drum brake installed in automobiles and the like.

0002

[Conventional technology]

Some drum brakes have a parking brake function. As an example of this , a pair of brake shoes that come into pressure contact with the brake drum to generate braking force when expanded. A strut is provided on the back plate so that it can be expanded and contracted, and a strut is attached to each of the brake shoes. The web engages with the notch formed in the web and extends between the brake shoes to connect the pair of brakes. Rotatably supported on either side of the rake shoe, when rotated the strut A brake shoe operating lever is provided that engages with the brake lever to expand the brake lever. Connect the other end to the brake shoe operating lever and the parking brake lever inside the vehicle. Some cables are connected at one end.

0003 With this drum brake, when you operate the parking brake lever inside the vehicle, the The force is transmitted to the brake shoe operating lever via the cable, and this brake The shoe operating lever rotates, which connects the other brake shoe via the strut. The shoe presses against the brake drum, and the reaction force causes one brake shoe to press against the brake drum. is expanded and presses against the brake drum to function as a parking brake.

0004

[Problem that the idea aims to solve]

By the way, in the drum brake mentioned above, one end of the cable is connected to the brake shoe. Although it is attached to the operating lever, this cable is attached to the back plate. The cable mount with the cable inserted into the cable mount hole that was created. Attach the tool, then move the brake shoe operating lever to a point where the work area is secured. Pull it out and connect one end of the cable to the lever for operating the brake shoe. I'm doing more. Therefore, the work is easier as the lever for operating the brake shoes is pulled out. In addition to being inconvenient, a tool was required for this pull-out operation.

[0005] In this case, in particular, drum brakes dedicated to parking brakes for drum-in discs Due to the order of the assembly process at the car manufacturer, the assembly of the cable in This is done after assembling it into the axle, but the axle is attached to the inner diameter part of the brake (so-called spigot). Since the boss (hub) of the brake shoe will be located as described above, When the operating lever is pulled out, the axle boss is located on the inner diameter of the brake. The space for assembling the cables is reduced, and the workability is even worse. It was becoming.

[0006] This invention was devised in view of the above problems, and the brake shoe operating lever Attach the cable to the lever for operating the brake shoe without pulling out the cable. The purpose of the present invention is to provide a drum brake that can improve the workability of assembling cables.

[0007]

[Means to solve the problem]

In order to achieve the above objectives, this invention has developed a back plate that is attached to a non-rotating part of a vehicle. It is installed in the seat so that it can be expanded, and when it is expanded, it comes into pressure contact with a drum attached to the rotating part of the vehicle. a pair of brake shoes that are connected to each other; , and the brake shoe is rotated by receiving the operating force via the cable. In a drum brake that has a brake shoe operating lever that expands the A locked portion having a larger diameter than the cable is provided at one end of the cable, and the brake At the tip of the shoe operation lever, there is an opening on the back plate side and the cable is inserted. has a groove into which the cable can be inserted, and when the cable is inserted into the groove, the cable is inserted into the groove at one end. A cable locking portion that locks the locking portion is provided, and the cable locking portion on the opening side of the groove is provided. The cable is covered with a part of the back plate opposite to the part near one end of the stop part. The present invention is characterized in that a convex portion is provided to guide the locking portion to the one end portion.

[0008] In addition, a working hole is formed in the part of the back plate that corresponds to the middle part of the cable. may be completed.

[0009]

[Effect]

With this configuration, the cable can be placed near the lever for operating the brake shoe. and connect the locked part of the cable between the back plate and the brake shoe operating lever. By positioning the cable in the position, the protruding part of the cable can be positioned at The cable is guided to one end, and finally, with the cable inserted into the groove, the locked part The cable is locked to the brake locking part and the cable can be assembled to the brake shoe operating lever. It is done.

0010 Form a working hole in the part of the back plate that corresponds to the middle part of the cable. This allows you to insert a tool, such as a screwdriver, into the working hole. This means that the middle part of the cable can be manipulated more easily.

[0011]

【Example】

Hereinafter, a drum brake according to an embodiment of the present invention will be explained based on the drawings. In addition, The drum brake in this example is a drum-in-disc duo-servo parking type. This is a drum brake that is fixed to a non-rotating part of the vehicle (not shown) in the figure. A pair of brake shoes 2 and 3 are attached to the back plate 1 so as to be freely expandable. ing. Each brake shoe 2, 3 has a T-shaped cross section with a rim 2a, 3a and a web 2b, 3b. The shoe bodies 2c, 3c fixed to the rims 2a, 3a and the lining material 2d attached to the outer peripheral surface ,3D. The outside of the brake shoes 2 and 3 has an axle (vehicle rotation A brake drum (not shown) that is fixed to a rotating section is arranged with a predetermined gap. ing.

0012 One end of each brake shoe 2, 3 contacts both ends of the adjuster 4, and It is elastically pressed by the spring 4A. In addition, each brake shoe 2, The other ends of 3 are connected to springs 6 and 7, respectively, which are interposed between the anchor pin 5. They are urged in a direction closer to each other. Moreover, each brake shoe 2, 3 is A shoe hold that engages with a shoe hold pin 8 installed upright on the back plate 1 It is urged toward the back plate 1 by a spring 9.

[0013] Notches 2e, 3e are formed near the other end of the webs 2b, 3b of each brake shoe 2, 3. The notches 2e, 3e are engaged with the recesses 10a, 10b formed at both ends. A strut 10 is stretched between the brake shoes 2 and 3. Also, one A lever 11 for operating the brake shoe is rotatable near the other end of the brake shoe 3. The other end of the lever 11 for operating the brake shoe is One end of cable 12 connected to the parking brake lever (not shown) of It is locked in place.

[0014] In addition, 13 in the figure indicates that the cable 12 is inserted movably and is drilled into the back plate 1. This is a cable attachment fitting that is fitted into the cable attachment hole 14 provided. 15 back It is a guide member welded to plate 1 and is designed to guide cable 12. There is. 16 is interposed between the cable mounting bracket 13 and the lever 11 for operating the brake shoe. It is a spring that returns the brake shoe operating lever 11 to its original position. It has become.

[0015] With this configuration, when the parking brake lever is pulled, cable 12 is The lever 11 for operating the brake shoe is rotated through the lever, and this rotation causes the strap to 10 presses the other brake shoe 2 to bring it into pressure contact with the brake drum, and The reaction force brings one brake shoe 3 into pressure contact with the brake drum. to this It will work more like a parking brake.

[0016] Next, main parts of the present invention will be explained based on FIGS. 1 to 4.

[0017] At one end of the cable 12, there is a caulking ball (locked part) with a diameter larger than that of the cable 12. ) 17 are provided. On the other hand, the tip of the brake shoe operating lever 11 has a , a substantially cylindrical protrusion 18 is provided, and a longitudinal direction of the protrusion 18 is provided on the side surface of the protrusion 18. A mounting groove 19 extending in the direction is formed with the opening 20 facing the back plate 1 side, Its bottom reaches the center of the protrusion 18. The width dimension of this mounting groove 19 is It is set wider than the outer diameter of 12 and narrower than the outer diameter of crimping ball 17. to this The cable 12 can be inserted into the mounting groove 19, and one brake shoe of the protrusion 18 can be inserted into the mounting groove 19. Attach a caulking ball 17 to one end 18a corresponding to the rim 3a side part of No. 3 (the front side of the paper in Fig. 2). It can be locked. Note that a recess 18b is formed in the center of one end 18a. The caulking ball 17 is accommodated in this recess 18b.

A convex portion 21 is provided in a portion of the back plate 1 on the opening 20 side of the mounting groove 19 facing the portion near the one end portion 18a, and a convex portion 21 is provided to secure the caulking ball 17 of the cable 12 to the one side. It is adapted to be guided to the side end portion 18a. Note that the cable 12 will be assembled to the brake shoe operating lever 11 as described later, but during this assembly work, the gap X between the cable 12 and the brake shoe operating lever 11 should be made so that the caulking ball 17 does not come into contact with it. Clearances Z _{1 and} Z ₂ are ensured in the initial state of one brake shoe 3 with respect to the rim 3a and in the state immediately before it is locked to the one end 18a (fits into the recess 18b).

[0019] Further, a portion of the back plate 1 corresponding to the intermediate portion 12a of the cable 12 A working hole 22 is formed in the working hole 22, and a screwdriver, for example, can be inserted into this working hole 22. so that the middle part 12a of the cable 12 can be manipulated or the inside can be visually inspected. ing. Note that 23 in the figure is a rubber plug for closing the working hole 22.

[0020] In a drum brake configured in this way, cable 12 is assembled as follows. I'm wearing it. First, insert the cable 12 into the cable mounting hole 14, and then Connect the cable 12 to the back plate by attaching the mounting bracket 13 to the back plate 1. 1. Next, attach the caulking ball 17 of the cable 12 to the back plate 1 and the brake. Position it between the key shoe operating lever 11 and insert the screwdriver into the working hole 22. By inserting the cable 12 into the middle part 12a of the cable 12, the cable 12 can be crimped. 17 is positioned between the protrusion 18 and the convex portion 21. Further in the middle of the cable 12 with a screwdriver By operating the portion 12a, the caulking ball 17 is guided along the convex portion 21 to the one end portion 18a. Along with this, the cable 12 is guided to the mounting groove 19, and finally the cable 12 is installed. The cable 12 is inserted into the groove 19, and the caulking ball 17 is accommodated in the recess 18b, causing the cable 12 to brake. It will be assembled to the shoe operating lever 11.

[0021] In this way, unlike the conventional one, the lever 11 for operating the brake shoe is pulled out. The cable 12 can be assembled to the lever 11 for operating the brake shoe without any trouble. It is done. Therefore, the work to pull out the lever 11 for operating the brake shoe is required. Work efficiency will be improved by the amount that is removed, and the work required for pulling out work will be reduced. No tools needed. In addition, as shown in Fig. 9, if the convex part is not provided, the back The caulking ball 17 is inserted into the gap 24 between the plate 1 and the lever 11 for operating the brake shoe. However, in the present invention, a protrusion 21 is provided to guide the caulking ball 17 into the mounting groove 19. Therefore, such problems will not occur.

[0022] In this embodiment, the case where the convex portion 21 is provided separately from the back plate 1 is taken as an example. , the present invention is not limited to this, but for example, as shown in FIG. The convex portion 25 may be formed by forming the plate 1 by, for example, press working.

[0023]

[Effect of the idea]

Since the present invention is a drum brake configured as explained above, the brake The cable brake shoe can be operated without pulling out the brake shoe operating lever. Since it can be assembled to the operating lever, the brake shoe operating lever can be pulled out. This improves work efficiency by eliminating the need for pulling out work, and reduces the specialized work involved in pulling out work. No tools required. It also corresponds to the middle part of the cable on the back plate. By forming a working hole in the part, a tool such as a screwdriver can be inserted into the working hole. The middle part of the cable can be manipulated by inserting it into the groove of the cable. can be inserted quickly and reliably.

[Brief explanation of drawings]

FIG. 1 is a partial front view showing a drum brake according to an embodiment of the present invention.

FIG. 2 is a sectional view taken in the direction of arrow II in FIG. 1;

FIG. 3 is a front view showing the drum brake.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a sectional view taken along the line V-V in FIG. 3;

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 3;

7 is a sectional view taken along the line VII-VII in FIG. 3. FIG.

8 is a sectional view showing another example of the convex portion in FIG. 2. FIG.

FIG. 9 is a sectional view showing a drum brake without a convex portion.

[Explanation of symbols]

1 Back plate 2 Brake shoes 3 Brake shoes 11 Brake shoe operation lever 12 cable 17 Caulk ball 18 Protrusion 18a One end 19 Mounting groove 20 opening 21 Convex part 22 Working hole

Claims (2)

[Scope of utility model registration request] Claim 1: A pair of brake shoes that are expandably provided on a back plate that is attached to a non-rotating part of a vehicle, and that, when expanded, come into pressure contact with a drum that is attached to a rotating part of the vehicle; In the drum brake, the drum brake has a brake shoe operating lever that is pivoted on one side and receives an operating force via a cable and rotates to open the brake shoe. A large-diameter locked portion is provided, and a groove is provided on the tip side of the brake shoe operating lever that opens toward the back plate and into which the cable can be inserted, and when the cable is inserted into the groove. A cable locking portion that locks the locked portion at one end thereof is provided, and a portion of the back plate facing a portion near the one end of the cable locking portion on the opening side of the groove, A drum brake characterized in that a convex portion is provided for guiding the locked portion of the cable to the one end portion. 2. The drum brake according to claim 1, wherein a working hole is formed in a portion of the back plate corresponding to the intermediate portion of the cable.