JPH0215731B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the manufacture of a drum brake back plate having a flat surface with steps, particularly a drum brake back plate in which a reinforcing plate is integrally combined with a closing plate. It is about the method.

[Prior Art] A back plate of a drum brake is fixedly supported on a non-rotating part of a vehicle, closes one end of the brake drum that rotates together with the wheels, and has a hydraulic cylinder device, an anchor member, and one end inside the brake drum. Supports twin brake shoes. As mentioned above, the back plate of a drum brake closes the inside of the brake drum to prevent dust from entering, and also serves to receive braking torque, so in order to reduce weight, the back plate should be made as thin as possible. , it is preferable to reinforce the portions that receive braking torque.

In the back plate of conventional drum brakes, the closing plate and the reinforcing plate are formed and perforated separately, and then the two are overlapped and joined together. Therefore, if the relative positions of the two become misaligned when they are joined, it may be difficult to attach them to the vehicle body. Gaps and inclinations occur in the surfaces and the support surfaces of the anchor members, making it impossible to achieve close overlap, causing errors in the level difference accuracy on both sides, and causing errors in the positions of mounting bolt holes and rivet holes.

[Problems to be Solved by the Invention] An object of the present invention is to provide a method for manufacturing a back plate of a drum brake, in which a relatively thin closing plate and a reinforcing plate are accurately overlapped, and the positions of various holes are not misaligned. Our goal is to provide the following.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the present invention is such that a mounting surface that surrounds the axle and is fixed to the vehicle body and a support surface that supports the anchor member of the brake shoe are provided. A method for manufacturing a back plate with a step, the first step being punching out a closing plate and a reinforcing plate from the back plate to form a mounting surface and a supporting surface, and predetermining the closing plate and the reinforcing plate on the mounting surface and the supporting surface. The second step is to closely overlap and connect the closing plate and the reinforcing plate with a step, and the third step is to punch an axle hole and an anchor member mounting hole in the overlapping surface of the closing plate and the reinforcing plate.
and a fourth step of connecting the anchor member to the closing plate and the reinforcing plate using rivets inserted into the anchor member mounting holes.
It consists of a process.

[Function] After the closing plate and the reinforcing plate are formed and combined by overlapping each other, axle holes and anchor member mounting holes are punched in the overlapping surface of the closing plate and the reinforcing plate, so the closing plate and the reinforcing plate overlap. The mating surfaces are accurately overlapped with a predetermined step difference between them, and there is no misalignment in the positions of the various holes between the closing plate and the reinforcing plate.

[Embodiments of the Invention] As shown in FIG. 1, the back plate according to the present invention consists of a closing plate 2 formed from a thin plate and a reinforcing plate 22 formed from a substantially rectangular plate, which are arranged in an axle hole. A flat mounting surface 23 surrounding the vehicle body 24
and are superimposed on each other with a substantially oval flat support surface 26 supporting the anchor member 35.

As shown in FIGS. 1 and 2, the closing plate 2 has an axle hole 4
A flat surface 1 that is higher than the mounting surface 3 and is connected in a ring shape to the outside of the mounting surface 3 surrounding the mounting surface 3 via an inclined surface 5.
2, and a hole 1 in the upper part of the flat surface 12.
A surface 34 having numbers 1, 14 is provided. This side 3
A hydraulic cylinder device is fitted into the hole 11 provided in the hole 14, and is fixed by a bolt screwed into the hole 14. A support surface 6 that is raised higher than the flat surface 12 is formed in the lower part of the closure plate 2 via an inclined surface 5a. A lower portion of the support surface 6 is connected to a flat surface 12 via an inclined surface 7.

As is well known, the left and right pair of brake shoes are engaged at their ends between the hydraulic cylinder device and the anchor member 35, and the central portion of the web of each brake shoe is inserted into the hole provided in the closing plate 2. The three flat legs 1 are lightly supported by the closing plate 2 through pins fitted and supported by the brake shoes 15 and springs (not shown), and one end of the rim of each brake shoe is slightly raised from the flat surface 12.
3.

A raised cylindrical portion 8 having an inverted U-shaped cross section is formed on the peripheral edge of the closing plate 2, and a cylindrical portion 9 is formed on the outer peripheral side of the cylindrical portion 8. The cylindrical part 8 is fitted into an annular groove formed on the open end surface of the brake drum so as not to contact the inside thereof, and the cylindrical part 9 is assembled so as to cover the outer circumferential side of the open end of the brake drum to prevent dust from entering the inside of the brake drum. Configures a dust shield to prevent dust from entering.

The reinforcing plate 22 has a flat mounting surface 23 surrounding the axle hole 24, both side edges are bent upward to form an inclined surface 25 as shown in FIG. 5, and the lower part is shown in FIG. The inclined surface 25a
through which a raised flat support surface 26 is formed;
The lower edge is bent downward to form an inclined surface 27.

The closing plate 2 and the reinforcing plate 22 are molded separately from each other, and the level difference between each mounting surface 3, 23 and each supporting surface 6, 26 is set to a predetermined value in advance. The mounting surfaces 3, 23 and the support surfaces 6, 26 are closely stacked on each other, and the mounting surfaces 3, 23 and the support surfaces 6, 26 are superimposed on each other in a direction perpendicular to the mounting surfaces 3, 23 and parallel to the mounting surfaces 3, 23 by spot welding or by means described later. They are connected so that there is no relative movement in the direction.

Axle holes 4, 24 and bolt holes 17 are provided in the center of the mounting surfaces 3, 23, and rivet holes 38 are provided in the support surfaces 6, 26, as shown in FIG. Holes 11, bolt holes 14, holes 15, etc. are provided in the closing plate 2.

The anchor member 35 is constructed by overlapping an anchor plate 32 for engaging the end of the web of the brake shoe on the support surface 26 and a retainer 33 for suppressing the web so that it does not come off, and fixing them with rivets 31. be done.

As shown in Figures 1 and 4, the closing plate 2 and the reinforcing plate 2
A hole 16 is provided in the inclined overlapping portion with 2 to guide a remote control cable connecting the parking brake lever and the handbrake lever into the inside of the brake drum.

Next, a method for manufacturing a drum brake back plate according to the present invention will be described. First, the closure plate 2 is formed into a predetermined shape. At that time, the short cylindrical parts 8 and 9 are formed by deep drawing the peripheral parts.

Separately, after forming the reinforcing plate 22 into a predetermined shape, stack the reinforcing plate 22 on the closing plate 2 so that the mounting surface 23 is on the mounting surface 3 and the supporting surface 26 is on the supporting surface 6. The mounting surface 23 and the support surface 26 are pressed inside the mold so that they have a predetermined step (dimension), and the closing plate 2 and reinforcing plate 22 are joined together by spot welding. At that time, the error in the level difference between the mounting surfaces 3, 23 and the support surfaces 4, 24 in the closing plate 2 and reinforcing plate 22 is eliminated by the gap between the inclined surfaces 25a and 5a and the gap between the inclined surfaces 27 and 7 (No. Figure 2).

However, even without welding, as shown in FIG. 6, for example, a plurality of protrusions 37 can be integrally formed between the inclined surfaces 5 and 25 from the inside to the outside using a punch or the like. For example, closing plate 2 and reinforcing plate 2
Relative movement in the direction perpendicular to the overlapping plane of 2 is suppressed,
As shown in FIG. 7, if a plurality of protrusions 36 are integrally formed on the overlapping surfaces of the closing plate 2 and the reinforcing plate 22,
Relative movement in the direction parallel to the overlapping surfaces of the closing plate 2 and the reinforcing plate 22 is suppressed, and the closing plate 2 and the reinforcing plate 22 can be coupled to each other.

Next, with the closing plate 2 and the reinforcing plate 22 superimposed, the axle hole 24 and the belt hole 1 are formed in the mounting surfaces 3 and 23.
At the same time as punching 7, rivet holes 38 are punched in the supporting surfaces 6, 26. In addition, a hole 11 in the closing plate 2,
Punch out bolts 14, holes 15, etc.

Finally, the anchor plate 32 and retainer 33 are stacked on top of the support surface 26, and are integrally joined with the rivets 31 inserted through the holes 38 to complete the back plate.

[Effects of the Invention] As described above, the present invention provides a method for manufacturing a back plate having a step between a mounting surface that surrounds an axle and is fixed to the vehicle body and a support surface that supports an anchor member of a brake shoe. First, the closing plate and reinforcing plate are punched out from the back plate to form the mounting surface and the supporting surface.
a second step in which the closing plate and the reinforcing plate are tightly overlapped and connected with a predetermined step between the mounting surface and the supporting surface; and the axle hole and the anchor member mounting hole are formed in the overlapping surface of the closing plate and the reinforcing plate. Since the method is comprised of a third step of punching, and a fourth step of joining the anchor member to the closing plate and the reinforcing plate by means of rivets inserted into the anchor member attachment holes, the following effects are achieved.

(a) The closing plate and the reinforcing plate are overlapped at a predetermined step on the mounting surface to the vehicle body and the supporting surface of the anchor member, and the drawing error of both is due to the mutual slope between the mounting surface and the supporting surface. This is solved by the gap between.

(b) Since axle holes, bolt holes, rivet holes, etc. are punched out after the closing plate and the reinforcing plate are stacked and joined together, there is no deviation in the position of the holes between the closing plate and the reinforcing plate. Therefore, the mounting position of the hydraulic cylinder device, brake shoe, etc. to the back plate is accurate, and the precision of assembling the back plate to the vehicle body is improved.

(c) If a large number of protrusions are integrally formed on the flat overlapping surface and the inclined surface of the closing plate and the reinforcing plate to join the closing plate and the reinforcing plate, welding will be unnecessary and costs will be reduced. is reduced.

[Brief explanation of drawings]

FIG. 1 is a front view of the back plate of a drum brake according to the present invention, FIG. 2 is a side sectional view of the same, FIG. 3 is a sectional view taken along the line - in FIG. 1, and FIG. 4 is a sectional view taken along the line - in FIG. FIG. 5 is a sectional view taken along the line - in FIG. 1, and FIGS. 6 and 7 are sectional views showing means for connecting the closing plate and the reinforcing plate. 2: Closure plate, 3, 23: Mounting surface, 4: Axle hole,
6, 26: Support surface, 17: Bolt hole, 22: Reinforcement plate, 5a, 25a: Inclined surface, 35: Anchor member,
36, 37: protrusion, 38: rivet hole.

Claims (1)

[Claims] 1. A method for manufacturing a back plate having a step between a mounting surface that surrounds an axle and is fixed to the vehicle body and a support surface that supports an anchor member of a brake shoe, the method comprising: a closing plate; A first step in which reinforcing plates are punched out from the back plate to form a mounting surface and a supporting surface, and a second step in which the closing plate and reinforcing plate are closely overlapped and combined with a predetermined step difference between the mounting surface and the supporting surface. , a third step of punching an axle hole and an anchor member mounting hole in the overlapping surface of the closing plate and the reinforcing plate, and a fourth step of joining the anchor member to the closing plate and the reinforcing plate using rivets inserted through the anchor member mounting holes. This is a method for manufacturing the back plate of a drum brake. 2. According to claim 1, the closing plate and the reinforcing plate are joined by integrally forming protrusions on the mounting surface, the supporting surface, and the inclined surface existing between the mounting surface and the supporting surface of the closing plate and the reinforcing plate. The method for manufacturing the drum brake back plate described.