JPS59150621A - Bending method of metallic plate - Google Patents

Abstract

PURPOSE:To bend a metallic plate having a small bent radius without causing cracks, etc. at the bending part by providing a hole of an optional dimension having its center at the position slightly deviated with respect to the central positon of bending, to the plate, in bending the plate in approximately the same direction as that of roll marks. CONSTITUTION:A proper-sized hole 3 having its center line B at the position slightlly deviated with respect to the bending center line A of a metallic plate 1, is provided to the plate 1 to bend it at the line A. As a result, it is seen that the direction of roll marks 2 near the bending part changes to the radial direction of the hole 3 as shown by the figure, and the sufficient bending characteristics are obtained even if the plate 1 is bent by an inside radius equal to the plate 1 thickness. Accordingly, this method is sufficiently practicable in the field of electronic parts where the component parts are highly required to be small and accrate.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of bending a metal plate used for processing terminals of variable resistors and the like.

Conventional structure and its problems Conventionally, when bending terminals made of metal materials constituting a variable resistor, the inner radius R of bending is generally equal to the thickness of the metal plate 1, as shown in FIG. is required, especially for phosphor bronze, nickel silver, etc. for springs, which has an R of 1.6 to 3 times the thickness of the nail material.
is necessary. On the other hand, in recent years, as the demand for smaller size, higher precision, and higher density of component parts has increased, it is desired to reduce the radius R of bending by 2 -W--... to streamline costs. hoop processing of metal plate-shaped parts (such as terminals, etc.) has become common for
There have been cases where the bending direction and the bending direction have to match. In such a case, if the bending radius R is made too small, there are problems such as cracks occurring at the bent portion or the bent portion becoming brittle.

Purpose of the Invention The present invention has been made in view of such conventional problems, and is an attempt to reduce the radius of bending without causing cracks in the bent portion where the direction of the roll grain and the bending direction almost coincide with each other. The purpose is to provide a method for bending plates.

Structure of the Invention In order to achieve the above object, the metal plate bending method of the present invention is such that when bending is performed in substantially the same direction as the roll grain direction, the bending process is performed at a position slightly shifted from the center position of the bending process. By forming a hole with an appropriate size at the center and performing the bending process, it is possible to reduce the bending radius of the 3-page bending process.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. In the present invention, as shown in FIG.
A hole 3 of an appropriate size with a center line B is provided at a position slightly shifted from the center line A of the bending process, as shown in FIG. I have to. By bending the metal plate 1 along the center line A of the bending process in this way, it can be seen that the two directions of the roll marks near the bending are changing toward the center of the hole 3, as shown in FIG. It was.

This is thought to be because the degree of elongation of the material during bending is different due to the holes 3.

Figure 4 shows the relationship between the material thickness and the inner radius R of bending to obtain the required characteristics by the method of the present invention and the conventional method. Compared with curve B by the conventional method, curve A by the method of the present invention is smaller. It is explained that the necessary bending characteristics can be obtained by adjusting the inner diameter R.

This Figure 4 shows the characteristics of phosphor bronze for springs.Effects of the Invention As described above, the metal plate bending method of the present invention is configured, and the bending process is performed slightly deviated from the center line of the bending process. By providing a hole of an appropriate size with its center line at the position and bending it in approximately the same direction as the roll grain direction, sufficient bending characteristics can be obtained even with an inner radius of bending that is equivalent to the thickness of the material. Its practicality is great in the field of electronic components, where there is a high demand for smaller component parts and higher precision.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the bending state of a metal plate by the conventional processing method, Fig. 2 is a top view of the metal plate explaining the present invention in detail, and Fig. 3 is a bending of the metal plate by the processing method of the present invention. FIG. 4, which is a perspective view showing the state, is a diagram showing the relationship between the material thickness and the inner radius of bending to obtain the necessary characteristics by the method of the present invention and the conventional method. 1...Metal plate, 2...Roll, 3.
... Hole, A6 page ... Center line for bending, B ...
- Center line of the hole. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4 shows Prefectural Figure 1 Procedural Amendment 1 Case 1988 Patent Application No. 24017 2 Name of Invention Metal Plate Bending Process 3 Relationship with the Amendment Case Patent Application
Colonel Tokoro 1006 Oaza Kadoma, Kadoma City, Osaka Name (582) Matsushita Electric Industrial Co., Ltd. Representative Yama
Toshihiko Shimo 4 Agent 571 Address 2, Matsushita Electric Industrial Co., Ltd., 1006 Kadoma, Kadoma City, Osaka Prefecture Figure 2 Figure 3 Figure 4 Materials 1

Claims (1)

[Claims] A metal plate having a hole at the center of the warp is bent using a line in the direction of the roll grain which is slightly shifted from a line formed between the center position and the direction of the roll grain as a center line. Bending method.