JP2818966B2 - Method and apparatus for manufacturing brake dust shield - Google Patents

Description

The present invention relates to a method and an apparatus for manufacturing a brake dust shield.

[Conventional technology and its problems]

The brake dust shield 60 has an annular shape having an L-shaped cross section as shown in FIG. 7, and is fixedly welded to the outer periphery of the backing plate main body 61 of the drum brake. Has a dustproof function between the brake drum 62 rotating with the wheels. Conventionally, such a dust shield 60 is manufactured by, for example, a drawing method from a steel flat plate, a spatula drawing method from a steel strip, or the like.

In the method of drawing from a steel flat plate, a pressing device as shown in FIG. 8 is used, a rectangular steel flat plate 50 shown in FIG. 9 is placed on a trim punch and flange up die 51, and The fixed punching punch 53, flange up punch 54, and trim die 55 are integrally lowered, and the steel plate 50 is punched in an annular shape by the punching punch 53 and trim die 55, and subsequently, by the flange up punch 54. It is formed into an annular body having an L-shaped cross section.

However, in such a conventional method of drawing from a steel flat plate, since the rectangular steel flat plate 50 is punched in a ring shape, the material yield is poor, and about 70% is scrapped as scraps 56 and 57. .

On the other hand, a spatula drawing method from a steel strip is a method in which a steel strip of a predetermined length is R-bent into an annular shape, and the butted ends of the annular body are welded and fixed, and then a spatula is drawn to form an L-shaped cross section. Into an annular body having

However, such a conventional method of drawing a spatula from a steel strip requires a lot of processing time and a large number of steps, is inefficient in production, and it is difficult to form a high-precision annular body at the time of butt welding. Good products are easy to produce.

In order to solve the technical problem in such a conventional method of manufacturing a brake dust shield, a brake dust shield disclosed in Japanese Patent Application Laid-Open No. 58-181409 has been proposed. This dust shield cuts a part of both end edges of a strip-shaped material obliquely, forms an intermediate material having a substantially L-shaped cross section having plate surfaces orthogonal to each other from the material, and attaches the intermediate material to one plate surface. Is roll-rolled so that the rolling rate is greater than that of the other plate surface, and is manufactured into an annular body having a substantially L-shaped cross section.

However, in such a conventional method of manufacturing a dust shield,. Cutting obliquely a part of both edges of the strip-shaped material,. Fold the material and make it almost L
Forming an intermediate material with a V-shaped cross section; Rolling the intermediate material with different rolling rates and rolling it into an annular body having a substantially L-shaped cross section, the number of steps is low and the production efficiency is low, and the intermediate material is roll-rolled with different rolling rates, Due to the flange up, it is difficult to form the flange uniformly and well.

[Means for solving the problem]

The present invention has been made in view of such a conventional technical problem, and the structure of the invention described in claim (1) is as follows.
A dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape is received in an annular notch on the outer periphery of the die, and a lower portion of the lower surface and the inner peripheral surface of the dust shield material are supported by the annular notch, With the outer peripheral surface of the dust shield material supported by a vertically movable ring member, a punch having an annular curved surface is lowered, and the upper portion of the dust shield material is directed inward by the annular curved surface. The ring member and the cushion pad are lowered together with the punch while the lower surface of the inwardly bent part of the dust shield material is supported by a vertically movable cushion pad, and the bending is advanced. , Pressing the upper portion of the dust shield material between the upper surface of the cushion pad and the upper surface of the die, and the lower surface of the punch and the annular curved surface to form an inward flange. A brake dust shield manufacturing method of forming a.

According to a second aspect of the present invention, there is provided an annular notch for receiving a dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape and supporting a lower portion of the dust shield material and a lower portion of an inner peripheral surface. A ring member which is disposed on the outer periphery of the die so as to be vertically movable and urged upward by first pressing means to support the outer peripheral surface of the dust shield material; A piston member movably arranged up and down on the inner periphery of the die, and urged upward by a second pressing means; and a piston member arranged on the piston member, and from the upper surface of the die when the piston member is raised. The dust shield material protrudes and supports the lower surface of the inwardly bent portion of the dust shield material, and when the piston member descends, it is locked to the projection of the die to restrict the lowering position. Press against part An upper portion of the dust shield material fixed to the punch pad and the punch holder and bent by an annular curved surface formed on the lower surface is pressed between the upper surface of the cushion packet and the upper surface of the die, and an inward flange is formed. And a punch forming a portion.

[Action]

However, according to such a method of manufacturing a dust shield for a brake, a dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape is used, and this dust shield material is received in an annular notch on the outer periphery of a die. The lower portion of the inner peripheral surface of the shield material is supported by the annular cutout portion, and the upper portion of the dust shield material is bent inward by the annular curved surface of the punch. Since the surface is supported by the ring member and the annular curved surface of the punch, buckling is effectively prevented even when a vertical compressive force acts on the dust shield material.
Also, with the progress of the bending process of the dust shield material,
The upper edge of the dust shield material tends to bend downward, but this bending deformation is prevented well by supporting the inwardly bent part of the dust shield material on the upper surface of the cushion pad. Is done.

In this way, the bending is advanced, and the upper part of the dust shield material is pressed between the upper surface of the cushion pad and the upper surface of the die, and the lower surface of the punch and the annular curved surface to form an inward flange portion.

Further, according to the manufacturing apparatus of the brake dust shield, a dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape is used. First, the ram is raised, and the punch holder and the punch take the top dead center position. At this time, the ring member is urged by the first pressing means to be at the ascending position, and the cushion pad is urged by the second pressing means to be appropriately driven to ascend. In this state, the dust shield material is inserted into the annular notch of the die, the lower surface of the dust shield material and the lower part of the inner peripheral surface are supported by the annular notch, and the outer peripheral surface of the dust shield material is It is supported by a member.

Next, the ram is lowered, and the punch holder and the punch are lowered. Then, in a state where the annular curved surface of the punch and the inner peripheral surface of the ring member are connected, the punch is lowered, and the ring member is lowered via the first pressing means,
The upper edge of the dust shield material is brought into contact with the annular curved surface of the punch, and this contact portion is bent inward along the annular curved surface to gradually form an inward flange. At this time, the upper portion of the dust shield material, which is bent inward along the annular curved surface, enters between the upper surface of the cushion pad and the lower surface of the punch.

In bending such a dust shield material, the outer peripheral surface of the dust shield material is supported by the annular curved surface of the punch and the inner peripheral surface of the ring member, and the lower portion of the inner peripheral surface is as described above. Thus, since it is supported by the annular notch of the die, buckling due to the compressive force acting on the dust shield material in the vertical direction can be prevented well.
Further, as the bending process of the dust shield material progresses, the inwardly bent portion of the dust shield material tends to bend downward.
Since it is restrained by the upper surface of the cushion pad urged upward by the pressing means, it can be prevented well.

When the punch holder and the punch reach the bottom dead center, the upper portion of the dust shield material is sufficiently bent inward, and the upper portion is formed between the upper surface of the cushion pad and the upper surface of the die, and the lower surface of the punch and the annular curved surface. Therefore, a dust shield having a predetermined shape having an inward flange portion is formed.

After raising the punch holder to the top dead center, take out the dust shield.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

 1 to 6 show one embodiment of the present invention.

FIG. 2 shows a dust shield material 1. The dust shield material 1 is formed into a short cylindrical shape by rounding a strip-shaped steel plate (thickness of about 0.5 to 1.2 mm) by R-bending. Such a dust shield material 1 has an inward flange portion 2a formed at one end by a press device described later, and is formed into a dust shield 2 shown in FIG.

The press device for forming the dust shield 2 from the dust shield material 1 has a substantially symmetrical structure as shown in FIG. In FIG. 1, reference numeral 3 denotes a die holder, on which an annular die 4 is fixed as shown in FIG. An annular notch 4a is formed in the upper part of the outer periphery of the die 4, and the annular notch 4a receives the lower portion of the annular dust shield material 1 and forms the lower surface 1a and the inner surface of the dust shield material 1 shown in FIG. The lower part of the peripheral surface 1b is supported. The upper surface 4b connected to the annular notch 4a of the die 4 is chamfered at a corner to form a curved surface. A lower part of the inner periphery of the die 4 forms a cylinder part 4c into which the piston member 5 is slidably fitted. Above the cylinder part 4c, there is a projection that regulates a lowering position of a cushion pad 6 described later. An annular cross section 4d is formed.

A ring member 7 is arranged on the outer periphery of the die 4 so as to be vertically movable. The ring member 7 is constantly elastically urged upward by a spring 8 as a first pressing means, and supports the outer peripheral surface 1c of the dust shield material 1 shown in FIG.

The piston member 5 fitted to the cylinder portion 4c of the die 4 is
The airtightness is maintained by the seal ring 5a, and the die holder 3
1 is driven upward by compressed air supplied from the through hole 3a. In this way, the annular cushion pad 6 placed on the piston member 5 is
The second pressing means elastically urges upward.

On the other hand, an annular punch 10 fixed to the punch holder 9
The outer periphery of the lower surface 10a of the inner peripheral portion is connected to an upwardly convex annular curved surface 10b, and the outer peripheral portion forms a short cylindrical portion 10c.
The upper surface of the dust shield material 1 is located between the lower surface 10a and the annular curved surface 10b of the punch 10 and the upper surface 6b of the cushion pad 6 which is engaged with the upper surface 4b of the die 4 and the cross section 4d of the die 4 to assume a lowered position. Is pressed to form an inward flange portion 2a.

An annular cavity 11 is formed in the punch holder 9, and the annular cut punch 12 is vertically movable in the cavity 11.
Is inserted. The cut punch 12 exerts a shearing action between its lower outer peripheral edge and the upper inner peripheral edge of the cushion pad 6 to finish the inner peripheral portion of the inward flange portion 2a. The lower peripheral edge of the cut punch 12 is immersed in the punch 10. Then, this press machine,
It comprises a double-acting press with two rams which act on the punch 10 and the cut punch 12 separately.

Next, a process of forming the dust shield 2 using the press device having such a configuration will be described.

First, as shown in FIG. 4, each ram outside the figure is raised,
The punch holder 9, the punch 10, and the cut punch 12 are set to the top dead center position. At this time, the ring member 7 urged by the spring 8 is at the raised position, and the piston member 5 is appropriately driven to be raised by the compressed air supplied from the through hole 3a of the die holder 3. In this state, the dust shield material 1 is inserted into the annular notch 4a of the die 4, and the lower surface 1a and the lower portion of the inner peripheral surface 1b of the dust shield material 1 are supported by the annular notch 4a. An outer peripheral surface 1c of the material 1 is supported by a ring member 7. Thus, the dust shield material 1 is held so that buckling is favorably prevented with respect to the vertical compressive force.

Next, one ram is lowered, and the punch holder 9 and the punch 10 are lowered. As a result, as shown in FIG. 5, with the annular curved surface 10b of the punch 10 connected to the inner peripheral surface of the ring member 7, the short cylindrical portion 10c of the punch 10 compresses the spring 8 and Is pressed down, the upper end edge of the dust shield material 1 abuts against the annular curved surface 10b of the punch 10, and this abutting portion is bent inward along the annular curved surface 10b, and is gradually narrowed down to a flange shape. go. At this time, the lower surface 10a of the punch 10 and the upper surface 6 of the cushion
5, the piston 4 is appropriately lowered so as to maintain a predetermined interval L as shown in FIG.
Inside, the dust shield material 1 bent inward is received.

Thus, when bending the dust shield material 1, the outer surface 1c of the dust shield material 1
The annular curved surface 10b and the inner peripheral surface of the ring member 7 support the lower portion of the inner peripheral surface 1b, as described above, by the annular notch 4a of the die 4. Buckling due to the compressive force acting on the dust shield material 1 in the vertical direction is favorably prevented. Thus, the ring member 7
While the bending process is performed on the dust shield material 1, the dust shield material 1 always moves integrally with the punch 10. Therefore, if the top dead center position of the punch 10 is set so that the dust shield material 1 can be mounted, It is also possible to form the ring member 7 and the punch 10 integrally.

Further, as the bending process of the dust shield material 1 progresses, the inner end portion of the dust shield material 1 that has entered the space L tends to be bent downward. The upper end of the inner peripheral surface 1b, that is, the lower surface of the inwardly bent portion is supported by the upper surface 6a of the cushion pad 6, which is elastically urged upward by pneumatic pressure. Is done.

When the punch holder 9 and the punch 10 reach the bottom dead center, the upper part of the dust shield material 1 is sufficiently bent inward as shown in FIG.
6a and the upper surface 4b of the die 4, the lower surface 10a of the punch 10, and the annular curved surface 10b, the upper part of the dust shield material 1 is pinched, and the dust shield 2 having a predetermined shape having an inward flange portion 2a is formed. can get. At this time, the cushion pad 6 is locked on the step surface 4d of the die 4 and restrained from descending.

Next, the cutter punch 12 is driven downward to shear the excess inner peripheral portion of the inward flange portion 2a.
Is finished well. Cutting waste associated with this shearing
14 drops into the recess of the piston member 5.

When the processing of the inward flange 2a is completed, the punch 10
After raising the cutter punch 12 to the top dead center, the dust shield 2 is taken out.

〔The invention's effect〕

As understood from the above description, according to the present invention, the following effects can be obtained.

. The dust shield can be formed by using a dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape and bending the upper part of the dust shield material using a press device. Good material yield.

. The outer peripheral surface of the dust shield material is supported by the annular curved surface of the punch and the inner peripheral surface of the ring member, and the lower portion of the dust shield material is supported by the annular notch of the die. Therefore, buckling is well prevented, and a dust shield having a good shape can be obtained.

. When forming the inward flange of the dust shield material, the upper end of the dust shield material is supported by the cushion pad, and the downward bending deformation of the dust shield material is prevented. A dust shield having the same can be obtained.

[Brief description of the drawings]

1 to 6 show one embodiment of the present invention, FIG. 1 is a sectional view showing a pressing device, FIG. 2 is a perspective view showing a dust shield material, FIG. 3 is a sectional view showing a dust shield, FIG. Four,
FIG. 5 is an explanatory view of the operation, FIG. 6 is a partial sectional view showing the die, FIG. 7 is a sectional view showing the state of attachment of the dust shield, FIG. 8 is a sectional view showing a conventional pressing device, and FIG. It is a perspective view which shows a steel flat plate. 1: Dust shield material, 1a: lower surface, 1b: inner peripheral surface, 1c: outer peripheral surface,
2: Dust shield, 2a: Inward flange, 3: Die holder,
4: Die, 4a: annular notch, 4b: upper surface, 4c: cylinder, 4d: step surface (projection), 5: piston member (second pressing means), 6: cushion pad, 6a: upper surface, 7: ring Member, 8: Spring (1st
Pressing means), 9: punch holder, 10: punch, 10a: lower surface, 10b:
Annular curved surface, 10c: short cylinder, 12: cut punch.

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takashi Goto 1190 Kajiro, Iwatsuki-shi, Saitama Prefecture Akebono Brake Industry Co., Ltd. Akebono Brake Industry Co., Ltd. Iwatsuki Works (56) References JP-A-56-168920 (JP, A) JP-A-59-129423 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , (DB name) B21D 53 / 26,53 / 34 F16D 65/00

Claims (2)

(57) [Claims] A dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape is received in an annular notch on the outer periphery of a die, and the lower surface of the dust shield material and the lower portion of the inner peripheral surface are defined by the annular notch. While the outer peripheral surface of the dust shield material is supported by a vertically movable ring member, a punch having an annular curved surface is lowered, and the dust shield material is reduced by the annular curved surface. The upper part is bent inward, and the ring member and the cushion pad are lowered together with the punch while supporting the lower surface of the inwardly bent part of the dust shield material by a vertically movable cushion pad. The bending process is advanced, and the upper portion of the dust shield material is pressed between the upper surface of the cushion pad and the upper surface of the die, and the lower surface of the punch and the annular curved surface to press the inner portion. Brake dust shield method for producing and forming a can flange. 2. A die which receives a dust shield material obtained by rounding a strip-shaped plate into a short cylindrical shape, and has an annular notch on the outer periphery for supporting a lower portion of the dust shield material and a lower portion of an inner peripheral surface thereof; A ring member urged upward by a first pressing means to support an outer peripheral surface of the dust shield material, and a ring member movably arranged vertically on an inner periphery of the die. A piston member which is urged upward by the second pressing means, and which is disposed on the piston member and which projects from the upper surface of the die when the piston member is lifted and faces inward of the dust shield material. Along with supporting the lower surface of the bent part, when the piston member descends, it is locked to the projection of the die and the descending position is regulated,
A cushion pad pressed into contact with an upper part of the dust shield material, and an upper part of the dust shield material fixed to a punch holder and bent by an annular curved surface formed on a lower surface, the upper surface of the cushion pad and the upper surface of the die. And a punch forming an inward flange portion by sandwiching between them.