JPH07328736A - Bending method for wire - Google Patents

Abstract

PURPOSE:To provide a wire bending method which reduces variance in dimension by removing deformation in wire parts and which also dispenses with the expectation of spring back. CONSTITUTION:A waveform rugged part 2g is formed with a prescribed pitch P1 in the axial direction, by metallic dies 8, 9, on the wire of the wire parts 2A, 2B that are bent in the prescribed shape of parts. A wedge shaped recessed part is formed in steps with a prescribed pitch P2 in the axial direction, in place of the waveform rugged part, on the inclined parts 2b, 2c of the wire part 2B. The wire parts are the core wires 2A, 2B of a sun visor for automobiles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire bending method, and more particularly to an optimum bending method for a core wire of an automobile sun visor.

[0002]

2. Description of the Related Art Generally, for example, an automobile sun visor 1A.
Is, as shown in FIG. 4A, at both ends 2d and 2e of the core wire 2A formed by bending the wire into a rectangular frame shape,
After fixing the holder part 3 as shown in FIG.
As shown in (C), a pad (not shown) is applied, and the pad is covered with the outer skin 4 together with the core wire 2A.

Further, like the sun visor 1B shown in FIG. 5B, the inclined portions 1b and 1c are bent at a predetermined angle a (for example, about 12 degrees to 15 degrees) in order to conform to the roof shape of the passenger compartment. In the case of the type formed in (2), both sides of the core wire 2B need to be formed in the inclined portions 2b and 2c as shown in FIG. 5 (A).

The camber bend molds 5 and 6 of the latter type of core wire 2B are flat molds in which flat parts 2a and 2a of the core wire 2B are set in a lower mold (die) 5 shown in FIG. 6 (A). The flat type part 5 is provided with the part 5a.
While the inclined mold parts 5b and 5c are provided on both sides of a, as shown in FIG.
The upper die (punch) 6 shown in (B) is also provided with similar flat die portions 6a and inclined die portions 6b and 6c, and the upper die 6 is lowered D
To allow the core wire 2B to have inclined portions 2b, 2
forming c.

[0005]

However, in the camber bend molds 5 and 6, since the molding surfaces of the flat mold portions 5a and 6a and the inclined mold portions 5b and 6b are both flat flat shapes, the wire Since the distortion (warping or twisting) in the previous step of bending into a rectangular shape cannot be removed, the dimensional variation after bending (bending) the inclined portions 2b and 2c into the core wire 2B is very large. There was a problem. Further, the springback due to the residual stress of the inclined portions 2b and 2c of the core wire 2B is also large, and the inclined portion portions 5b and 6b of the camber bend type 5 and 6 are also large.
However, there was also the problem that it had to be manufactured at an angle that allowed for springback.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wire bending method which eliminates strain of wire parts to reduce dimensional variation and eliminates the possibility of springback.

[0007]

In order to achieve the above object, the present invention is to bend a wire into a predetermined part shape, and then to form a corrugated uneven portion at a predetermined pitch in the axial direction on the wire. The present invention provides a method for bending a wire characterized by forming the wire. In addition to forming the corrugated uneven portion on the flat surface of the wire-bent component and forming the inclined portion inclined from the flat surface, the inclined portion is stepped at a predetermined pitch in the axial direction. A wedge-shaped recess may be formed. Further, it is optimal that the part obtained by bending the above wire is a core wire of an automobile sun visor.

[0008]

According to the present invention, corrugated uneven portions are formed in a wire at a predetermined pitch in the axial direction on a wire of a wire component bent into a predetermined component shape. Thereby, since the entire wire is plastically deformed by the fine uneven portion, the strain in the previous step is removed, and if the wire part is formed with the inclined portion, the variation in the dimension after bending is reduced, Wire parts with stable shapes. Also, since the inclined part is also plastically deformed by the wedge-shaped concave part in a stepwise manner,
Residual stress is removed, springback is reduced, and there is no need for springback in the inclined mold part of the mold.
It becomes a wire part with a more stable shape.

The above wire component is most suitable for the core wire of a sun visor for automobiles, and the core wire 2 of the type that forms the inclined portions 2b and 2c as shown in FIG. 5 (A).
In addition to B, the core wire 2A of the type shown in FIG.

[0010]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. It should be noted that parts having the same configurations and functions as those of the prior art shown in FIG. As shown in FIG. 1, among the camber bend molds 8 and 9 forming the inclined portions 2b and 2c on both sides of the core wire 2B for the automobile sun visor 1B, the lower mold (die) 8 has a structure shown in FIG. )
As described above, the flat mold portions 8a, 8b, and 8c for setting the flat surface portions 2a and 2a of the core wire 2B (the lengths are respectively l
a, lb, lc), and the flat mold portions 8a to 8
On both sides of c, inclined mold portions 8e, 8f, 8g (lengths are le, lf, lg) for bending the inclined portions 2b, 2c of the core wire 2B are provided. In addition, the inclined mold portion 8f,
Between 8g, the plane type | mold part 8d (length is ld) which sets the rear end plane part 2f of the inclination part 2c of the core wire 2B is provided. The wire of the core wire 2B is, for example, SW.
M-B It is an ordinary iron wire, its thickness is 3.2 mm,
There are 3.5 mm, 4.0 mm, etc.

Each of the flat mold portions 8a to 8d is shown in FIG.
As will be described in detail, the molding surface is not flat, and square wave-shaped uneven portions 8h and 8i are formed at a predetermined pitch P1 in the axial direction of the core wire 2B. For example, the width W1 of the concave portion 8h is 10 mm, the width W2 of the convex portion 8i is 5 mm, and therefore the pitch P1 is 15 mm.

Further, each of the inclined portions 8e to 8g is shown in FIG.
As shown in detail in (A), the molding surface is not flat, and stepped recesses 8j are formed at a predetermined pitch P2 in the axial direction of the core wire 2B. The pitch P2 of the recess 8j is set in relation to the inclination angle α (degree). For example, α
If the (degree) is less than 2 degrees, the uneven portions are formed at the same pitch P1 as that of the flat portions 8a to 8d. It may be flat. If α (degrees) is 2 degrees or more and less than 3 degrees,
The pitch P2 is 15 mm. If the angle is 3 degrees or more and less than 5 degrees, the pitch P2 is 10 mm. If it is 5 degrees or more, the pitch P2 is 7 mm. In addition, this pitch P2
From the height W3 of the recess 8j and the width W4 of the recess 8j,
It can be calculated as W3 squared + √W4 squared = P2.

Although not specifically shown, the flat wall portions 9a to 9d and the inclined wall portions 9e to 9g of the upper die (punch) 9 do not have a flat molding surface, and like the lower die 8, they have a rectangular shape. The corrugated concave and convex portions 9h and 9i and the stepped concave portion 9j are formed.

The flat wall portions 8a to 8d of the lower mold 8 have square wave-shaped uneven portions 8h and 8i, whereas the flat wall portions 9a to 9d of the upper mold 9 have square wave-shaped uneven portions 9h and 8i. 9i
Shift by about 1/2 pitch in the axial direction. In addition, with respect to the stepped concave portion 8j of the inclined wall portions 8e to 8g of the lower mold 8,
The stepped concave portion 9j of the inclined wall portions 9e to 9g of the upper mold 9 is
It is displaced in the axial direction by a predetermined dimension x. When the pitch P2 is 7 mm, the appropriate displacement x is 2 mm along the inclination angle α (degree) from the reference line S, for example.

If the camber bend molds 8 and 9 are constructed as described above, after the holder portion 3 is fixed to both ends 2d and 2e of the core wire 2B formed by bending the wire into a predetermined shape, the core wire 2B is fixed. 2B is set at a predetermined position of the lower mold 8 shown in FIG. And the upper die 9
Is lowered D, the inclined portions 2b, 2 are attached to the core wire 2B.
c is formed.

At this time, the flat portion 2 of the core wire 2B
a and 2f are plane mold portions 8a to 8 of the lower mold 8 and the upper mold 9.
Since the uneven portions 8h, 8i, 9h, 9i of d, 9a to 9d are plastically deformed by the fine uneven portions 2g, ..., 2g having a square wave shape as shown in detail in FIG. Distortion (warping and twisting) will be removed.

At the same time, the inclined portion 2b of the core wire 2B,
2c is the inclined mold parts 8e to 8g of the lower mold 8 and the upper mold 9,
As shown in detail in FIG. 3 (B), the recesses 8j and 9j of e to 9g are wedge-shaped recesses 2h, which are stepwise in the axial direction.
.., 2 h, so that the residual stress is removed and the spring back is reduced.

Flat portions 2a, 2f of the core wire 2B
By removing the strain of the core wire 2B, the dimensional variation after bending (bending) the inclined portions 2b and 2c on the core wire 2B is reduced, and the core wire 2B having a stable shape is formed.
Becomes Further, the residual stress of the inclined portions 2b and 2c of the core wire 2B is removed and the spring back is reduced, so that the inclined die portions 8e to 8g of the lower die 8 and the upper die 9 are formed.
The possibility of spring back of e to 9 g is also unnecessary, and the core wire 2B has a more stable shape.

In the above-mentioned embodiment, the core wire 2B for the sun visor 1B is used. However, in the case of the core wire 2A for the sun visor 1A, the lower mold 8 and the upper mold 9 are provided with the inclined mold portion 8a.
By providing a flat mold portion having a square wave-shaped uneven portion instead of e to 8g and 9e to 9g, the strain in the previous step can be removed, and the core wire 2A having a stable shape can be obtained.

Further, in the above embodiment, the core wires 2A and 2B of the sun visors 1A and 1B for automobiles are used, but it goes without saying that the present invention can be applied to other wire parts.

[0021]

As is apparent from the above description, in the wire bending method of the present invention, since the corrugated uneven portion is formed on the wire of the wire component, the entire wire is plastic with a fine uneven portion. Since the wire component is deformed, the strain in the previous step is removed, and if the wire component is formed with the inclined portion, the dimensional variation after bending is reduced, and the wire component has a stable shape. In addition, since the inclined part is also plastically deformed in the wedge-shaped concave part in a stepwise manner, residual stress is removed and springback is reduced, and the possibility of springback of the inclined mold part of the mold is unnecessary and the shape is more stable. High quality wire parts.

The above wire part is most suitable for the core wire of the sun visor for automobiles, but it can be applied to other wire parts.

[Brief description of drawings]

FIG. 1 is a camber bend type of the present invention, (A)
Is a plan view of the lower mold, and (B) is a side view of the camber bend mold.

FIG. 2A is a sectional view of a concavo-convex portion of a flat mold portion, and FIG.
Is a side view of the wire after processing

3A is a cross-sectional view of a concave portion of an inclined mold portion, and FIG. 3B is a cross-sectional view of a wire after processing.

4A is a perspective view of a core wire that is not bent, FIG. 4B is a perspective view of a core wire with a holder portion fixed, and FIG. 4C is a perspective view of a sun visor.

FIG. 5 (A) is a perspective view of a core wire that is bent and has a holder portion fixed, and (B) is a perspective view of a sun visor.

FIG. 6 is a conventional camber bend type, (A) is a plan view of a lower mold, and (B) is a side view of the camber bend type.

[Explanation of symbols]

1A, 1B ... Sun visor, 2A, 2B ... Core wire,
2a, 2f ... Plane part, 2b, 2c ... Inclined part, 2g, 2h
... Concavo-convex part, 3 ... Holder part, 8 ... Lower mold, 8a-8d ...
Flat mold portion, 8e to 8g ... Inclined mold portion, 8h, 8i ... Square wave-shaped uneven portion, 8j ... Stepwise concave portion, 9 ... Upper mold, 9a
-9d ... Planar part, 9e-9g ... Inclined part, 9h, 9i
... Square wave-shaped uneven portion, 9j ... Stepped concave portions, P1, P
2 ... pitch.

Claims (3)

[Claims] 1. A method for bending a wire, which comprises bending the wire into a predetermined component shape and then forming corrugated irregular portions at a predetermined pitch in the axial direction on the wire. 2. The corrugated concavo-convex portion is formed on a plane portion of the wire-bent component, and an inclined portion inclined from the plane portion is formed, and at the same time, a predetermined axial direction is formed on the inclined portion. The method for bending a wire according to claim 1, wherein the wedge-shaped recesses are formed stepwise at a pitch. 3. The method of bending a wire according to claim 1, wherein the component obtained by bending the wire is a core wire of an automobile sun visor.