JPH10220443A - Oval bolt, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the pressing, and reduce the manufacturing cost through weight reduction by forming a screw on the outer circumferential surface of large diameter of a flat hollow pipe of oval section. SOLUTION: A flat hollow pipe of oval section is used for an oval bolt 1, and a screw 4 is cut on the outer circumferential surface 3 of large diameter of a flat hollow pipe 2. In manufacturing the bolt 1, a metallic round pipe is used, the metallic round pipe is pressed at each side by a press to form a flat hollow pipe. The screw 4 having the prescribed depth and pitch is cut for completion in the outer circumferential surface 3 of large diameter of the flat hollow pipe. The manufactured oval bolt is hollow in the center part, little material is used and the weight is reduced, and the threading area is small, and the work is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oval bolt and a method of manufacturing the same, and more particularly, to an oval bolt which is hollow, light and easy to manufacture, and a method of manufacturing the same.

[0002]

2. Description of the Related Art As a conventional oval bolt of this type, an oval bolt 51 shown in FIG. 4 is generally used. This oval bolt 51 has a structure in which a screw 52 is provided by cutting the entire outer peripheral surface of a round bar steel material, and upper side surfaces of the round bar steel material are cut off to provide offset planes 53 on both sides. I have.

[0003]

However, since the conventional oval bolt 51 uses a solid round bar made of metal such as steel or stainless steel, the bolt itself is heavy and expensive. was there. Also, after forming the screw 52 on the entire outer peripheral surface of the bolt, it is necessary to cut the upper side surfaces to form the uneven plane 53, which makes processing difficult and increases the cost of the product. there were.

The oval bolt and the method of manufacturing the same according to the present invention are a completely new technique developed in view of the above-mentioned conventional problems, and particularly, a flat hollow pipe is used. It is an object of the present invention to provide a technique of an oval bolt in which a screw is provided only on a large-diameter outer peripheral surface of a portion.

[0005]

SUMMARY OF THE INVENTION An oval bolt according to the present invention is a technique which fundamentally solves the above-mentioned problems of the conventional oval bolt. An oval bolt characterized in that a screw is provided on a large-diameter outer peripheral surface of a flat hollow pipe having a rectangular shape.

The method of manufacturing an oval bolt according to the present invention is also a technique which is a fundamental improvement of the above-described conventional method of manufacturing an oval bolt, and the gist of the invention is to press a metal round pipe. A method for manufacturing an oval bolt, comprising: forming a flat hollow pipe having an oval cross section; and cutting a screw on a large-diameter outer peripheral surface of the flat hollow pipe to manufacture a bolt.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an oval bolt according to the present invention and a method of manufacturing the same. FIG. 1 is a perspective view of the oval bolt according to the present invention, and FIGS.
(C) is an explanatory view showing a step of manufacturing the oval bolt of FIG. 1, and FIG. 3 is a side view and a longitudinal sectional view of the oval bolt.

1 and 3, reference numeral 1 denotes an oval bolt according to the present invention. The oval bolt 1 uses a flat hollow pipe 2 having an oval cross section, and a large diameter outer peripheral surface 3 of the flat hollow pipe 2 is formed by cutting a screw 4.

In manufacturing the oval bolt 1 according to the present invention, as shown in FIG. 2, a metal round pipe 21 as shown in FIG.
Is pressed on both sides to form a flat hollow pipe 22 as shown in FIG. 2 (B). Next, by cutting a screw 4 having a predetermined depth and a pitch on the large-diameter outer peripheral surface 3 of the flat hollow pipe 22, the above-described oval bolt 1 shown in FIG. 1 or FIG. 3 can be manufactured.

In the present invention, as described above, since the round pipe 21 made of metal is used, a flat hollow pipe having an oval cross section is formed by pressing the metal round pipe 21 to easily compress both sides thereof. 22 can be formed. Also,
In forming the screw 4, only the large-diameter outer peripheral surface 3 of the flat hollow pipe 22 needs to be cut, so that the screw processing area is small and the work is easy. The oval bolt 1 manufactured as described above has a feature that the center portion is hollow and the material is small and light.

[0011]

The oval bolt and the method of manufacturing the same according to the present invention have the above-described structure and operation, and therefore have the following significant effects.

(1) Since the center of the bolt is hollow,
Easy material cost and light weight. (2) Therefore, the handling is convenient and the transportation cost can be reduced.
(3) Processing is easy because the screw processing area is small.
(4) It can be mass-produced at extremely low cost as compared with the above-mentioned conventional oval bolts.

[Brief description of the drawings]

FIG. 1 is a perspective view of an oval bolt according to the present invention.

2 (A), 2 (B), and 2 (C) are explanatory views showing steps of manufacturing the oval bolt of FIG. 1, respectively.

FIG. 3 is a side view and a longitudinal sectional view of an oval bolt.

FIG. 4 is an explanatory perspective view showing a conventional oval bolt.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Oval bolt 2 Flat hollow pipe 3 Large diameter outer peripheral surface 4 Screw 21 Metal round pipe 22 Flat hollow pipe 51 Oval bolt 52 Screw 53 Flat plane

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kuniyuki Ichikawa 1-22-2 Nishishinjuku, Shinjuku-ku, Tokyo Haneda Hume Kanko Co., Ltd.

Claims (2)

[Claims] An oval bolt characterized in that a screw is provided on a large-diameter outer peripheral surface of a flat hollow pipe having an oval cross section. 2. A method of forming a flat hollow pipe having an oval cross section by pressing a metal round pipe, and further manufacturing a bolt by cutting a screw on a large-diameter outer peripheral surface of the flat hollow pipe. A unique method of manufacturing oval bolts.