JPS6234022Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a screw attachment part, and more specifically, to an improvement of a screw attachment part in a thin plate.

[Prior Art] In a conventional screw mounting section, when a pilot hole is drilled and threaded in a thin plate where two or more threads cannot be removed, the pilot hole is first drilled in the thin plate 1, as shown in Fig. 1a, as an example. A burring process is performed to have a hole diameter equal to , that is, a process of driving a punch into a small hole to enlarge the hole diameter and forming a flange 2 protruding to one side on the hole edge, as shown in Figure 1b. By tapping screws 3 on the inner circumferential surface of the terminal, three to four threads are tapped, and a member 4 to be mounted, such as a terminal board, is mounted with mounting screws 5, as shown in Fig. 1c. There is.

[Problems to be solved by the invention] In this case, if the thickness of the plate is thin, only two to two and a half threads can be threaded at most, as shown in Figure 1b.
Moreover, in the case of a relatively soft metal such as a copper plate, the screws tend to become loose, and when connecting two conductors as part of an electric circuit, this causes problems such as connection failures and other accidents. In order to eliminate these defects, a thick plate is used, and the thickness of the plate is reduced by cutting the area other than the area where the screw hole is drilled, that is, the area where the conductor contacts, or the thickness of the plate is thickened in this area by welding small pieces of the same material. However, the drawbacks are that materials are wasted, processing is time-consuming, and mass production is not possible.

[Means for solving the problem] This invention aims to eliminate the above-mentioned drawbacks, and its features are as follows:
A folded part 13 is formed by overlapping and folding the perforated plate 11A on the perforated plate 11A, and this folded part 13 has a shape in which the upper part is recessed into a dish shape with a smaller diameter than the inner diameter of the hole 11a of the perforated plate 11A. At the same time, a flange 16 made of the thin plate 11 is formed around the lower screw hole 15 of these screw holes 15, 15. By forming the screw holes 17, 17 by tapping the screw holes 17, 17, there is provided a screw mounting part that allows several threads to be cut in a thin plate where only one or two threads can be cut.

[Function] By interposing a perforated plate between the thin plate and the folded portion and forming a flange, a large number of screw threads can be provided, and the screw holes can be prevented from becoming obstructed.

[Example] Hereinafter, an example of this invention shown in the drawings will be described in detail.

As shown in FIG. 2a, for example, from the end 12 of a thin plate 11 such as a copper plate used for electrical wiring, etc., bend the hole inward by a distance corresponding to the position where the screw hole is to be provided and the size of the screw, etc. The folded portion 13 is folded 180 degrees with the perforated plate 11A in the middle and overlapped to form a screw hole installation portion 14, and then the perforated plate is attached to this screw hole installation portion 14 as shown in FIG. 11
Aiming at the hole 11a of A, screw holes 15, 15 and an annular collar 16 are formed by burring.
Furthermore, as shown in FIGS. 2c and 3b, if the screw holes 15, 15 are threaded with taps, it is possible to cut approximately three and a half threads.

Figures 2 d and 3 c show a state in which a member 19 to be attached, such as a terminal board, is attached to the screw attachment part 18 processed as described above with the attachment screw 20. Since half the number of screw threads are provided in the folded portion 13, the mounting screw 20 can be firmly tightened, so that the mounting screw is less likely to come loose.

[Effects of the invention] As described above, this invention involves interposing a perforated plate in the thin plate in which a screw hole is to be formed, folding the thin plate, drilling a pre-screw hole in this folded portion and the thin plate, Since this screw hole was tapped,
Compared to conventional methods, the number of screw threads can be increased by the number of threads that can be cut to fit the thickness of the thin plate, so there is no strain on the threads, and the mounting screws are less likely to loosen.
Since there is no need to use spring washers, it is easier to screw the parts to be attached, and there is no need for welding, which makes processing easier and cheaper. By setting the diameter to be somewhat large, the upper part of the screw hole formed by the burring of the folded portion is recessed into a dish-like shape, which has many effects such as guiding the screw insertion.

[Brief explanation of drawings]

1A to 1C are cross-sectional views according to the conventional processing order of the screw attachment part, and FIGS. Figures a to d are cross-sectional views according to the processing order, the third
Figures a to c are also perspective views. 11...Thin plate, 11A...Perforated plate, 12...
End part, 13... Folding part, 14... Screw hole installation part, 15... Screw pilot hole, 16... Flange, 17... Screw hole, 18... Screw mounting part, 19... Attached member, 20...Mounting screw.

Claims (1)

[Scope of utility model registration request] A folded portion 13 is formed by overlapping the perforated plate 11A on the thin plate 11 and folding it back.
3, a pre-screw hole 15 having a smaller diameter than the inner diameter of the hole 11a of the perforated plate 11A and having a concave upper part;
15, and each of these screw holes 15, 1.
A flange 16 made of the thin plate 11 is formed around the lower screw hole 15 of the holes 15, and each of the screw holes 1
5, 15 and screw holes 17, 17.
A screw mounting part formed by forming a