JPH1151029A - Fastening structure for thin plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a firm fastening even in case where a screwed part of a fixed member is thin by forming a projection higher than a peripheral edge around an insetion hole of a thin plate at the peripheral edge, inserting a shaft of a screw into the insertion hole, and screwing a thread part into the fixed member. SOLUTION: An insertion hole 4 is formed in a thin plate 1, and at a peripheral edge around the hole 4 four projections 5 are radially or crosswise press formed. After the thin plate 1 is superposed on a fixed member 2 with a burring part 6 and the hole 4 matched in their positions, a screw 3 is driven into a burring part. Then, a screw head 7 abuts on an upper face of the projections 5 so that no further screw-in operation is made unable, thereby preventing intrusion of non-thread part 9 into the burring part 6 while forming a female thread part on an inner surface of the burring part 6 by a male thread part 10 to ensure a complete fastening.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for fixing a thin plate member and another fixed member with small screws called screws.

[0002]

2. Description of the Related Art Hitherto, means shown in FIG. 9 has been used for fixing thin plates. In FIG. 9A, a is a thin plate having a screw insertion hole a1 formed therein, b is a fixed member having a burring portion b1, c is a screw, and the screw c is inserted into the burring portion b1 through the insertion hole a1. Screwed. This screw c
A head c1 and a shaft c2, and a head c1 at the shaft c2.
9B, a non-threaded portion c21 is formed as shown in FIG. 9 (B) for the convenience of forming the threaded portion c22, so that the thin plate a is thin or the burring portion b1 is formed.
If the screw c is screwed in and the back surface of the head c1 comes into contact with the thin plate a, the non-screw part c21 is located near the tip of the burring part b1, If the length of the portion engaged with the screw is insufficient, and if the screw c is further turned in this state, the force concentrates on the internal thread at the inner surface of the tip of the burring portion b1 and the burring portion b
1 is enlarged as shown in the figure, and the screw, which is commonly called, becomes ridiculous and cannot function as a screw.

In FIG. 9 (A), if the height of the burring portion b1 is increased, the length of the portion engaged with the screw becomes sufficient.
When the burring portion has a small diameter, it is difficult to increase the height of the burring portion b1.

As means for avoiding these problems, FIG.
As shown in (c), there is a means for providing a raised base part a2 around the insertion hole a1 of the thin plate a so that the screw part c22 engages with the entire burring part. The fixing member b may be deformed upward in the base a2 and become defective.

Also, if a counterbore screw having a structure in which a downward ring-shaped projection is provided around the lower surface of the screw head c1 is used,
Since the non-threaded portion is hidden inside the ring-shaped projection and does not come out of the threaded portion, the above-described disadvantage can be avoided for the time being. However, this counterbore screw is disadvantageously expensive.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to prevent the above-mentioned inconvenience from being caused by a non-threaded portion formed on a shaft portion even when a screw having a commonly used structure is used. I do.

[0007]

Means for Solving the Problems One of the means for solving the above problem is, as described in claim 1, a head, a head, and a shaft, and the shaft has a non-head near the head. A screw provided with a screw portion and a screw portion following the screw portion is screwed into another fixed member through an insertion hole formed in the thin plate member. In the peripheral portion of the screw, a convex portion higher than the peripheral portion is formed, the screw portion is screwed into the fixed member through the insertion hole of the thin plate member, and the back surface of the head of the screw is It is characterized by being pressed against the surface.

According to this means, the head portion and the non-threaded portion of the screw are supported in the upper position by the convex portion provided on the peripheral portion around the insertion hole of the thin plate member, and the fixed member is held on the back surface of the peripheral portion. Since it is supported, even if the screwed portion of the fixed member is thin, the screw portion is screw-engaged with the screwed portion and firmly screwed.

The second means comprises a head and a shaft, wherein the shaft is provided with a screw having a non-threaded portion near the head and a threaded portion following the head. In a screwing structure for a thin plate member, which is screwed into another fixed member through an insertion hole formed in the member, a base protruding from the thin plate member around the insertion hole of the thin plate member, Forming a concave portion recessed from the surface of the screw, screwing the screw portion into the fixed member through the insertion hole of the thin plate member, and pressing the back surface of the head of the screw against the surface of the base portion. Features.

According to this means, the head portion and the non-threaded portion of the screw are supported at the upper position by the base provided around the insertion hole of the thin plate member, and the fixed member is supported at the lower end of the concave portion. Even if the threaded portion of the fixed member is thin, the threaded portion is engaged with the threaded portion and is firmly screwed.

According to a third aspect of the present invention, in the first or second aspect, the screwed portion of the another fixed member is a burring portion formed on the fixed member. .

According to this means, the screw portion of the screw is screwed into the burring portion of the member to be fixed, and the screw portion forms an internal thread over the entire length of the burring portion, and is screwed firmly by screw engagement. .

[0013]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a thin plate member, 2
Is a fixed member, and 3 is a screw. As shown in FIGS. 2 to 4, an insertion hole 4 is formed in the thin plate member 1, and four ridge-shaped projections 5 are pressed radially, that is, in a cross shape on a peripheral edge 4 a around the insertion hole 4. It is molded. For the thin plate member 1 and the fixed member 2, for example, a steel plate having a thickness of about 0.5 mm is used, and the convex portion 5 has a chevron cross section, a height h and a width w of about 1 mm each, and a long length. The outer end is made to protrude from the screw head. In the illustrated embodiment, the number of the convex portions 5 is four, but the number of the convex portions 5 is an appropriate number from 2 to 8 for easily forming a mountain shape.

The fixed member 2 has a short cylindrical burring portion 6 formed by burring, and a screw 3 screwed into the burring portion 6 has a head portion 7 and a shaft portion 8. In the vicinity of the part 7, for the convenience of processing the thread part 10,
A non-threaded portion 9 having substantially the same height as the height h is formed, and a driver groove 11 is provided in the head 7.

When the thin plate member 1 is superimposed on the fixed member 2 with the burring portion 6 and the insertion hole 4 coincident with each other, and the screw 3 is screwed into the burring portion 6, the head 7 has a top surface of the convex portion 5 having a height h. Will not be able to be screwed any more.
The non-threaded portion 9 is prevented from entering the burring portion 6, while a female screw is formed on the inner surface of the burring portion 6 by the threaded portion 10 to obtain a complete screw connection.

Even if the burring portion 6 is pulled into the burring portion 6 by the screwing of the screw 3, the burring portion 6 does not work.
Since the upper surface of the fixed member 2 and its surroundings are pressed by portions other than the protrusions 5 of the thin plate member 1, that is, the lower surface of the peripheral portion 4a of the insertion hole 4, the fixed member 2 deforms upward. Never. Therefore, the thin plate member 1 and the fixed member 2 are securely connected without deformation.

FIGS. 5 and 6 show another embodiment in which four dot-like projections 12 are provided on the peripheral edge 4a of the insertion hole 4 of the thin plate member 1 instead of the projections 5 of FIGS. Is provided. The convex portion 12
Supports the back surface of the head 7 of the screw 3 shown in FIG.
The non-screw part 9 is separated from the fixed member 2. The number of the protrusions 12 is an appropriate number that can withstand the pressure of the head 7 of the screw 3.

FIGS. 7 and 8 show another embodiment, in which a base 13 and a concave portion 14 which is recessed from the surface of the base 13 are provided in the peripheral portion of the insertion hole 4 of the thin plate member 1. The depth to the lower end of the recess 14 is substantially the same as the height of the base 13,
When the screw 3 is pressed by the head 7 of the screw 3, the lower end of the recess 14 presses the fixed member 2. Recess 14
Can be set to an appropriate number that can withstand the pressure of the head 7 of the screw 3, and the shape thereof can also be a shape in which the point-like convex portions 12 in FIGS.

In the above-described embodiment, the burring portion 6 is provided on the fixed member 2. However, if the thickness of the fixed member 2 is such that an effective internal thread can be formed, the burring portion may be formed. The present invention can be applied to a non-fixed member.

[0020]

As is apparent from the above description, according to the first aspect of the present invention, the head of the screw is supported at the upper position by the convex portion provided at the peripheral edge of the insertion hole of the thin plate member, and the non-threaded portion is formed. Is also in the upper position, so that even if the screwed portion of the fixed member is thin, the complete screw portion is screwed in and firmly screwed. Further, since the fixed member is pressed by the lower surface of the portion other than the convex portion of the peripheral portion of the insertion hole,
This has the effect of preventing deformation caused by being pulled in by the screw.

According to the second aspect of the present invention, the head of the screw is supported at the upper position by the base provided at the peripheral portion of the insertion hole of the thin plate member, and the non-screw portion is also at the upper position. Even if the screwed portion is thin, there is an effect that the complete screw portion is screwed in and firmly screwed. Further, since the fixed member is pushed by the lower end surface of the concave portion, the fixed member can be prevented from being deformed by being pulled in by the screw, and the base can be prevented from being deformed by being pushed by the head of the screw. is there.

According to the third aspect of the present invention, the threaded portion of the screw is screwed into the burring portion of the fixed member to form an internal thread over the entire length of the burring portion, and the threaded portion is engaged with the female thread. Because of the structure, even if the member to be fixed is thin, there is an effect that the member can be firmly screwed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.

FIG. 2 is a plan view of the thin plate member of the embodiment.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a perspective view of the thin plate member.

FIG. 5 is a longitudinal sectional view of another embodiment.

FIG. 6 is a perspective view of the thin plate member of the embodiment.

FIG. 7 is a longitudinal sectional view of still another embodiment.

FIG. 8 is a perspective view of the thin plate member of the embodiment.

FIG. 9 is an explanatory view of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Thin plate member 2 ... Fixed member 3 ... Screw
DESCRIPTION OF SYMBOLS 4 ... Insertion hole 4a ... Peripheral part 5, 12 ... Convex part 6 ... Burring part 7 ... Head 8 ... Shaft part 9 ... Non-screw part 10
... Screw part 13 ... Base part 14 ... Recess

Claims (3)

[Claims] 1. A fixed member comprising a head portion and a shaft portion, wherein a screw having a non-threaded portion in the vicinity of the head portion and a subsequent threaded portion is passed through an insertion hole formed in the thin plate member. In the screw structure of the thin plate member, which is screwed into the thin plate member, a convex portion higher than the peripheral edge portion is formed around the insertion hole of the thin plate member, and the shaft portion of the screw is inserted through the insertion hole of the thin plate member. Screwing the screw portion into the fixed member, and pressing the back surface of the head of the screw against the surface of the convex portion,
Screw structure for thin plate members. 2. A fixed member comprising a head portion and a shaft portion, wherein a screw having a non-threaded portion in the vicinity of the head portion and a subsequent threaded portion is passed through an insertion hole formed in the thin plate member. In the screwed structure of the thin plate member, which is screwed into, around the insertion hole of the thin plate member, a pedestal portion raised from the thin plate member,
A recess is formed from the surface of the base, and the shaft of the screw is screwed into the fixed member through the insertion hole of the thin plate member, and the back of the head of the screw is pressed against the surface of the base. A screw structure for a thin plate member. 3. The screwing structure for a thin plate member according to claim 1, wherein the screwed portion of the other fixed member is a burring portion formed on the fixed member.