JP2001040874A - Cap for steel pipe with larger end - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cap for a steel pipe with larger end, for which a pushing force can be reduced in pressing in a cap body to the steel pipe with larger end and the assembly of the cap body to the steel pipe with larger end can be performed smoothly. SOLUTION: A cap body 2 for closing an opening at the end portion of a steel pipe 1 with larger end, and a leaf spring 3 attached to a bottom wall 22 of a cap body 2 are used in the configuration, the end portion of the leaf spring 3 is linked to the inner surface of the steel pipe 1 with larger end by the elastic deformation of the end portion of the leaf spring 3 and the cap body 2 is assembled to the steel pipe 1 with larger end, the leaf spring 3 stated above is attached to an outside center of a bottom wall 22 of the cap body 2, and both the side portions in the length direction are curved to the side respectively approaching the bottom wall.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cap used for closing an end of a steel pipe for thick ends used for assembling a concrete formwork, for example.

[0002]

2. Description of the Related Art Conventionally, as shown in Japanese Utility Model Publication No. 6-24371, for example, a cap of this type has a bowl-shaped portion A that can be fitted into a thick steel pipe 1 and this bowl-shaped portion A. And a plate spring D attached to the bottom wall of the bowl-shaped portion A, the cap body C having a flange portion B protruding from the upper edge of the upper end and abutting against the edge of the thick steel pipe 1. By pressing the bowl-shaped part A of the main body C into the opening of the thick steel pipe 1 while elastically deforming the leaf spring D into a curved shape, the end D2 is pressed against the inner surface of the steel pipe 1 to form a cap body. C is attached to the thick steel pipe 1 so that the opening of the thick steel pipe 1 is closed.

At this time, a first elastic deformation in which the whole leaf spring D is elastically deformed toward the bottom wall side of the bowl-shaped part A with a fulcrum at an attachment portion to the bottom wall of the bowl-shaped part A; A tip portion is elastically deformed in two stages of a second elastic deformation in which the tip portion elastically deforms toward the peripheral wall side of the bowl-shaped portion A with a contact portion between the peripheral portion of the bottom wall of A and the vicinity of the tip portion of the leaf spring D as a fulcrum. ing.

The leaf spring D disclosed in the above publication is fixed to the center of the bottom wall of the bowl A by a rivet E, and as shown by imaginary lines in FIG. It extends straight along the diagonal of the wall. Therefore, in order to press-fit the above-mentioned cap body C into the thick steel pipe 1, the linearly formed leaf spring D must be elastically deformed in a curved shape. There was a problem that a very large pressing force to withstand was required.

At the time of press-fitting, since the linearly formed leaf spring D is mounted on the opening, the cap body C protrudes above the opening. Therefore, it is difficult to position the cap body C when press-fitting it into the thick steel pipe 1. In addition, when the cap body C is pressed into the upper part of the cap body C with a hammer or the like, the reaction force of the leaf spring D is increased. As a result, the press-fitting tends to fail, and the cap body C cannot be smoothly assembled to the thick steel pipe 1.

[0006]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and reduces the pressing force when press-fitting a cap body into a steel pipe for thickening, thereby reducing the thickness of the cap body. An object of the present invention is to provide a cap for a thick steel pipe, which can be smoothly attached to a steel pipe.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, a cap for a thick steel pipe according to the present invention is provided.
And a leaf spring 3 attached to the bottom wall 22 of the cap body 2. The end of the leaf spring 3 is engaged with the inner surface of the thick steel pipe 1 by elastic deformation. In the cap of the thick steel pipe in which the cap body 2 is assembled to the thick steel pipe 1, the leaf spring 3 is attached to the outside center of the bottom wall 22 of the cap body 2, and Both ends 32, 33 in the longitudinal direction
Are curved to the side approaching the bottom wall.

[0008]

Embodiments of the present invention will be described below in detail.

The cap for the thick steel pipe shown in FIGS. 1 and 2 is attached to the opening at the longitudinal end of the thick steel pipe 1 having a rectangular cross section to close the opening. The cap spring 2 basically includes a cap body 2 for closing an end opening of a thick steel pipe 1 and a leaf spring 3 attached to a bottom wall of the cap body 2. The cap body 2 is attached to the thick steel pipe 1 by elastically deforming the portion and engaging the inner surface of the thick steel pipe 1.

[0010] More specifically, the cap body 2 is
An approximately square bowl-shaped portion 2a which can be loosely inserted into the opening of the end portion of the thick steel tube 1 and is formed integrally with the upper edge of the peripheral wall 21 in the bowl-shaped portion 2a. And a flange portion 2b contacting the edge. Further, the leaf spring 3 is fixed at its center in the length direction to the center of the outside of the bottom wall 21 in the bowl-shaped portion 2a with a rivet 30, and the leaf spring 3 is moved in a direction approaching the bottom wall of the bowl-shaped portion 2a. In a curved state, it is arranged along a diagonal line of the bowl-shaped portion 2a.

The above-mentioned cap body 2 and leaf spring 3
Are manufactured by pressing a steel plate.

The bowl-shaped portion 2a of the cap body 2
Projecting below the bottom wall 22 from the mounting side of the leaf spring 3 by press molding, in other words, from the lower surface of the bottom wall 22.
A convex portion 4 for regulating the mounting position of the leaf spring 3 with respect to the cap body 2 is formed, and a part of the convex portion 4 is cut out to form a drainage hole 5 in the convex portion 4. The water accumulated inside can be discharged to the outside through the drain hole 5.

Further, as shown in FIG. 3, the corner portions of the peripheral wall 21 of the bowl-shaped portion 2a facing the both ends in the longitudinal direction of the leaf spring 3 are moved inward toward the center of the bottom wall 22. And this inclined portion is connected to the thick steel pipe 1 of the leaf spring 3.
Avoiding portion 2 for avoiding contact of both ends in the longitudinal direction of the leaf spring 3 which is elastically deformed with the bowl-shaped portion 2a when engaged with the inner surface.
It is set to 3.

In the cap having the above structure,
With the press-fitting into the opening of the steel pipe 1 for a thick end, the leaf spring 3
However, as shown in FIG. 4, the elastic member is largely elastically deformed in a curved shape, and both end portions 32 and 33 in the longitudinal direction bite into the inner surface of the steel tube 1 with elasticity by the elastic restoring force of the leaf spring 3. This prevents the cap body 2 from coming off the steel pipe 1.

In the embodiment shown in the drawings, the leaf spring 3 is curved in advance in a direction approaching the avoidance portion 23 of the bowl-shaped portion 2a of the cap body. When press-fitting, the pressing force required to bend the leaf spring 3 can be reduced, so that the burden on the operator can be reduced.

Further, since the leaf spring 3 is formed in a curved shape in advance, the lower portion of the cap is connected to the thick steel pipe 1.
When press-fitting into the opening, the cap body 2 is already loosely inserted into the opening of the thick steel pipe 1, so that the cap body 2 can be smoothly assembled to the thick steel pipe.

Further, both ends 32, 33 in the longitudinal direction of the leaf spring 3 which is elastically deformed are formed on the peripheral wall 21 of the bowl-shaped portion 2a.
Is provided on the peripheral wall 21 of the bowl-shaped portion 2a when the press-fitting into the thick steel pipe 1 is performed. Without contact, the plate spring 3 is elastically deformed in a large curved shape, and a sufficient resilience is obtained in the leaf spring 3, so that the cap can be firmly attached to the thick steel pipe 1.

The cap body 2 is not limited to a steel plate, but may be made of a synthetic resin, for example. Further, both ends 3 in the length direction of the leaf spring 3 formed in a linear shape.
2 and 33 may be curved toward the avoidance portion 23.

[0019]

As described above, according to the present invention, the cap body 2 for closing the opening at the end of the thick steel pipe 1 and the leaf spring 3 attached to the bottom wall 22 of the cap body 2 are provided.
An end of the leaf spring 3 is engaged with the inner surface of the thick steel pipe 1 by elastic deformation so that the cap body 2 is assembled to the thick steel pipe 1. 3 is attached to the outer center of the bottom wall 22 of the cap body 2 and has at least both ends 32, 3 in the longitudinal direction thereof.
3 are curved toward the side approaching the bottom wall 22, respectively, so that when the cap is pressed into the opening of the thick steel pipe 1, the pressing force required to curve the leaf spring 3 can be reduced. Since it is possible, the burden on the worker can be reduced.

When the cap is pressed into the opening of the thick steel pipe 1, the lower part of the cap is already loosely inserted into the opening of the thick steel pipe 1.
Can be smoothly attached to the thick steel pipe 1.

[Brief description of the drawings]

FIG. 1 is a bottom view of a cap according to the present invention.

FIG. 2 is a plan view of the same.

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

FIG. 4 is a sectional view taken along the line XX in FIG. 2 in a state where the cap according to the present invention is attached to the thick steel pipe.

FIG. 5 is a partially cutaway sectional view of a conventional cap in use.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thick steel pipe 2 Cap main body 2a Bowl-shaped part 2b Flange part 22 Bottom wall 23 Avoidance part 3 Leaf spring 32, 33 Both ends

Claims (1)

[Claims] 1. A cap body (2) for closing an end opening of a thick steel pipe (1), and a leaf spring (3) attached to a bottom wall (22) of the cap body (2). An end of the leaf spring (3) is engaged with the inner surface of the thick steel pipe (1) by elastic deformation to attach the cap body (2) to the thick steel pipe (1). In the steel pipe cap, the leaf spring (3) is attached to the center of the outside of the bottom wall (22) of the cap body (2), and at least both ends (32) and (33) in the longitudinal direction are respectively provided with bottoms. A steel pipe cap for thick ends characterized by being curved toward a side approaching a wall.