JPS61195714A - Press bending method - Google Patents

Abstract

PURPOSE:To perform a press bending with making the motion of a metal die at higher speed without using a core by forming the inner side contact face in opposition to the motion direction of the punch for contact and by bringing the outer side contact face to the inner side contact face by the punch to support the forming part of the inner side contact face. CONSTITUTION:The bending part A of one part is bent at right angles and also the bending part B of another part is bent at right angles and the bending part C to locate at the inner side thereof is bent in acute angle, as per the figure (a) on the forming part of the end parts 5, 6 of the phosphor bronze plate removing the unnecessary part with punching. The bending part D to locate at the inner side than the part A as per the figure (b) is bent in the obtuse angle nearer to the right angle than the obtuse angle of the part C then. The parts D and C are bent at right angles and the tip of the part B is pressed and the contact face E thereof and the contact face F of the tip of the part A are abutted as per the figure (c). Thereafter the semi- fabricated item forming the semi-fabricated terminal being placed on the center projecting part of a die 11, namely end parts 5, 6 as per the figure (b) is pressed by punches 15, 16 to bend the part C and D at right angles and the terminal 1 having loop shaped sections 5, 6 is completed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a press bending method, in particular, to press bending a plate material into a loop-shaped cross section in which an outer abutting surface abuts an inner abutting surface. This invention relates to a method that does not require a core in processing equipment.

[Conventional technology]

FIG. 4 is an enlarged perspective view (a) and a right end view (o) of a crimp terminal, which is one product to which the present invention is applied.

In FIG. 4, a crimp terminal 1 press-formed from a phosphor bronze plate with a thickness of 0.2 mm includes a signal wire crimp part 2 and a male contact insertion part 3, and a pair of tongue pieces 4 facing each other in the vertical direction.
The front end 5 and rear end 6 of the insertion portion 3 are formed into a loop-shaped cross section that overlaps at the upper part, as shown in FIG.

FIG. 5 is a front view showing the main parts of a conventional apparatus for finishing and forming the ends 5 and 6 of a loop-shaped cross section, and FIG. 6 is a perspective view showing the main parts of the apparatus in an open state. However, FIG. 6 is smaller than FIG. 5.

5 and 5, 7 is a core that can be moved back and forth;
Reference numerals 8 and 9 are bending gougs that can be moved left and right, and the ends 5 and 6 were subjected to preliminary bending and then finished forming using a device (progressive die and press machine) using a core 7.

[Problem that the invention seeks to solve]

However, the square end portions 5 and 6 of the terminal 1 have external dimensions of 1.
The core 7 has a dimension of about 0.8 mm square at the portion facing the bending dies 8 and 9, and is easily damaged even if there is a slight flaw in the adjustment of the processing equipment.

At the same time, the core 7 obstructs the speeding up of the processing equipment because it requires countermeasures against catching when the core 7 is removed from the forming ends 5 and 6.

[Means for solving problems]

The above problem is solved by forming the inner abutting surface facing the direction of operation of the abutting punch in the process of press bending a plate material into a loop-shaped cross section in which the outer abutting surface abuts the inner abutting surface,
The problem is solved by the press bending method of the present invention, characterized in that the punch brings the outer abutment surface into contact with the inner abutment surface using at least a portion on which the inner abutment surface is formed.

[Effect]

According to the above means, it is possible to perform bending using the mechanical strength of the processed product, the core required in conventional equipment is no longer required, the equipment can be operated at high speed, and the setup prior to operation can be carried out. and facilitate maintenance.

〔Example〕

EMBODIMENT OF THE INVENTION Below, the Example which applied this invention to the manufacture of the terminal 1 is demonstrated using drawing.

Figure 1 (A), ([1), and (C) are crimp terminals 1
FIG. 2 is an end view for explaining the main process of forming the loop-shaped cross-sectional portions 5 and 6 of FIG. be.

In the first trace, the end portions 5 and 6 of the phosphor bronze plate from which unnecessary portions have been punched out are bent at right angles to one bent portion, and the other is bent at right angles to the bent portion B, as shown in Figure (A).
is bent at a right angle, and the bent portion C located on the inside thereof is bent at an obtuse angle.

Next, as shown in FIG. 1 (Il+), the bent portion located inside the bent portion A is bent to an obtuse angle that is closer to a right angle than the obtuse angle of the bent portion C.

Next, as shown in FIG. 1(C), bend the bent portion C at right angles, and press the tip from the bent portion B to form a contact surface E and a contact surface F of the tip from the bent portion A. and bring them into contact.

In FIG. 2, 11 is a fixed die, 12.13 is a bending die that can be slid in the left and right direction, 14 is a compression coil spring, and 15
, 16 is a slide punch, and 17 is a bending punch. The punches 15, 16, and 17 reciprocate up and down by the drive of the press machine, and the vertical movement of the punches 15.16 and the coil spring 14
The bending dies 12 and 13 reciprocate from side to side due to the elasticity of the spring.

In such a device, when the punch 15.16 moves downward, the bending die 12°1 whose shoulder is pressed by the punch 15.16
3 moves forward in the opposite direction (inward). And die 1
Punch 15.1 to punch the semi-finished terminal, that is, the semi-finished terminal whose ends 5 and 6 are formed as shown in FIG.
6 presses and bends bent portions C and D at right angles.

Then, punch 1 descends 1 tempo later than the above pressing.
7 presses the tip from the bent part B, corrects the right angle bend of the bent part B, and the tip from the bent part A and the tip from the bent part B contact (overlap), and the end of the loop-shaped cross section 5,6
Terminal 1 is completed.

However, the pressing force of the punch 17 is supported between the bent portions A and D and between the bent portions B and C, and the stroke of the punch 17 is set so that the pressing force does not cause buckling at the supporting member. has been done.

FIG. 3 is a diagram showing a loop-shaped cross-sectional shape according to another embodiment.

In FIG. 3, (A) is an example of a rectangular cross-section that abuts at one corner, (El) is an example of a circular cross-section that abuts at one middle part, and symbols G and H in the figure are contact surfaces.

The dotted line indicates the shape of the part to be bent in the final process.

[Effects of the Invention] As explained above, according to the present invention, a part of the processed member is used to eliminate the need for a core required in conventional molds, which speeds up the operation of the mold and facilitates production. The effects of improved performance and ease of setup and maintenance before driving are remarkable.

[Brief explanation of drawings]

FIGS. 1(<), (o), and (11) are end views for explaining the main steps of forming a loop-shaped cross-sectional end of a crimp terminal according to an embodiment of the present invention, and FIG. 2 is an end view of the end. Figure 3 (() (o) is a front view for explaining the main structure and operation of the mold for finishing forming the part.
4 is an enlarged perspective view (a) and a right end view (b) of a crimp terminal, which is a product to which the present invention is applied, and FIG. FIG. 6 is a front view showing the main parts of a conventional apparatus for finishing and forming a loop-shaped cross-sectional end, and FIG. 6 is a perspective view showing the main parts of the apparatus in an open state. In the figure, 1 is a crimp terminal, 5.6 is a loop-shaped cross section of the crimp terminal, F and G are inner abutting surfaces, and E and H are outer abutting surfaces. Na1 zu Ryo 2 zu (a) (b) Shu 3
Shoes

Claims (1)

[Claims] In the process of press bending a plate material into a loop-shaped cross section in which an outer abutting surface abuts an inner abutting surface, the inner abutting surfaces are formed to face each other in the operating direction of the abutting punch, and at least the inner abutting surface is formed. A press bending method characterized in that the punch brings the outer contact surface into contact with the inner contact surface using the bent portion as support.