JP2001212613A - Pipe, sheet metal for pipe and method of forming pipe using sheet metal for pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe capable of stably bringing a joint part into close contact though it is formed only by press forming without being welded in mass production since spring back is absorbed in press forming by fitting together which is prevented from coming out accompanying the deformation of a male engaging portion. SOLUTION: The joint 15 is composed of an end face 14a of one edge 14 of faces 11, 14 crossing each other and a back face 11b of the other edge 11a. A projecting portion 14c projecting from the end face 14a of the edge 14 is engaged with a recessed portion 11c formed on the other edge 11 and the joint 15 is in close contact in the state of fitting together being prevented from coming out against recessed portion 11c by the derformation of the projecting portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe having a closed cross-section formed by joining seams with edges having surfaces intersecting each other, a metal plate for the pipe, and a pipe using the metal plate for a pipe. The present invention relates to a method for molding a body.

[0002]

2. Description of the Related Art Conventionally, a technique described in Japanese Patent Application Laid-Open No. H11-290940 is known as a technique for manufacturing a pipe body, for example, a prismatic pipe body by bending a metal plate.

[0003] In this publication, a rectangular metal plate is used as a raw material, and a rectangular pipe body is formed by press working in a plurality of steps.

[0004] That is, in this method of processing a prismatic pipe body, the widthwise opposite ends of the metal plate are bent at right angles in the same direction along the lengthwise direction to form a flange portion facing each other and a flange portion facing each other. A first bending step of forming a primary molded product having a bottom plate portion to be connected, forming a concave curved surface of a predetermined width along the length direction on the bottom plate portion of the primary molded product, and both ends of the concave curved surface; Is bent inward at a substantially right angle to form a pair of two side walls having a pair of side walls facing each other and having a substantially U-shaped cross section.
The method includes a second bending step of forming the next molded article, and a restriking step of pressing a pair of side walls of the secondary molded article inward to abut the end faces of the pair of flanges.

[0005] According to the method for processing a prismatic pipe body, when a secondary molded product is formed, a concave curved surface formed on a bottom plate portion of the secondary molded product has a pair of side wall portions facing each other inward. In order to fulfill the function of suppressing the springback force generated by pressing, a prismatic pipe body having a rectangular cross section in which the end surfaces of the flange portions are in close contact with each other without welding the end surfaces of the flange portions is manufactured only by press molding.

[0006]

However, in this conventional method for processing a prismatic pipe body, when a secondary molded product is formed, a concave curved surface formed on a bottom plate portion of the secondary molded product has a pair of side wall portions. Although they have the function of suppressing the springback force generated by pressing the inwardly toward each other, the springback force that tries to open outward remains on the pair of side walls, and during mass production, It has been difficult to stably manufacture a prismatic pipe body in which the end surfaces of the flange portions are in close contact with each other without variation.

That is, when an inspection is performed to determine whether or not the end surfaces of the flange portions of the prismatic pipe body manufactured by this processing method are in close contact with each other, there is certainly a case where the end surfaces are substantially in close contact with each other. In addition, there are quite a few cases in which a gap is generated between the end faces due to springback, and the gap also varies.

[0008] The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to stably adhere to a seam while being formed only by press forming without welding during mass production. It is an object of the present invention to provide a pipe body, a sheet metal for the pipe body, and a method for forming a pipe body using the pipe body sheet metal.

[0009]

In order to achieve the above object, according to the first aspect of the present invention, a joint is formed by an end face of one edge of a face intersecting each other and a back face of the other edge. In the pipe body having a closed cross-section, the male side engaging portion protruding from the end surface of the one edge engages with the female side engaging portion formed on the other edge, and the male side The gist is that the edges are in close contact with each other in a fitted state in which the engagement portion is prevented from coming off by the deformation of the engagement portion.

According to the configuration of the first aspect, the springback at the time of press forming is absorbed by the fitting which is prevented from coming off due to the deformation of the male side engaging portion, and the respective edges come into close contact with each other. It has a pipe body.

According to a second aspect of the present invention, a deformable male engaging portion is projected from an end face of one edge of a rectangular sheet metal,
A metal plate for a pipe body, wherein a female side engaging portion engageable with the male side engaging portion is provided at an edge portion parallel to the one edge portion.

[0012] According to the configuration of the second aspect, a sheet metal for a pipe body for providing a pipe body having a pair of edges closely contacted by a predetermined pressing step can be obtained. Can be easily carried out.

According to a third aspect of the invention, the amount of protrusion of the male side engaging portion from the end face is larger than the thickness of the rectangular sheet metal.

According to the third aspect of the present invention, since the projecting amount of the male engaging portion from the end face is larger than the thickness of the sheet metal, the male engaging portion can be easily deformed by the press machine. be able to.

According to a fourth aspect of the present invention, the amount of protrusion of the male side engaging portion from the end surface is substantially the same as the thickness of the rectangular sheet metal.

According to the fourth aspect of the present invention, since the projecting amount of the male engaging portion from the end face is substantially the same as the thickness of the sheet metal, the male engaging portion is deformed by the press machine after the deformation. The tip of the side engaging portion is unlikely to protrude from the surface, and the flatness of the surface can be easily ensured.

According to a fifth aspect of the present invention, the female-side engaging portion is a concave portion opened to the end face of the other edge portion and is set wider than the width of the male-side engaging portion. That is the gist.

According to the fifth aspect of the present invention, the engagement of the male side engaging portion with the female side engaging portion can be easily performed.

The gist of the invention described in claim 6 is that the recess has a smaller opening diameter near an open end than an opening diameter near a bottom edge.

According to the structure of the sixth aspect, when the male-side engaging portion is deformed, the fitting with the female-side engaging portion can be performed easily and reliably.

According to a seventh aspect of the present invention, the pipe body sheet metal according to any one of the second to sixth aspects is bent along a pair of parallel edges to form a plurality of surfaces, and A male engagement protruding from one end face of the parallel edges, wherein the faces having the pair of parallel edges intersect with each other and the pair of parallel edges face each other in a spaced state. The point is that after engaging the portion with the female side engagement formed on the other edge to form a seam, the male side engagement portion is deformed and fitted to the female side engagement portion. .

According to an eighth aspect of the present invention, a pipe body sheet metal according to any one of the second to sixth aspects is bent along a pair of parallel edges to form a plurality of surfaces, and A surface having the pair of parallel edges intersects among the plurality of surfaces and the pair of parallel edges are opposed to each other in a separated state to form a first surface.
A first step of obtaining a processed product, and forming a seam by engaging a male-side engaging portion protruding from one end face of the parallel edge with a female-side engagement formed on the other edge. The gist of the present invention includes a second step of obtaining a second processed product and a third step of deforming the male-side engaging portion and fitting the deformed male-side engaging portion to the female-side engaging portion to obtain a pipe body.

According to the seventh and eighth aspects of the present invention, a pipe body having a seam can be formed by a simple pressing process only, and the female fitting portion is fitted by deformation. Fitting can be performed in the pressing process.

[0024]

Next, an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1) In FIG.
Is a pipe body of the present invention. The pipe body 1 is formed in a square prism having four surfaces 11, 12, 13, and 14, and the surface 11 and the surface 1 that intersect each other (in this case, are orthogonal).
4 are joined together with the edges 11a and 14a,
The seam 15 is formed by the end surface 14b of the edge portion 14a abutting against the back surface 11b of 1a.

The edges 11a and 14a are enlarged views of the main parts before the formation of the pipe body 1 is completed, as shown in FIGS. 1B and 1C.
As shown in FIG. 5, a concave portion 11c (female side engaging portion) and a convex portion 14c (male side engaging portion) are formed so as to face each other in a direction crossing (orthogonal to) each other. This projection 14c
FIG. 1 is an enlarged view of a main part in a state where the formation of the pipe body 1 is completed.
As shown in (D) and (E), the depression 1
1c, thereby forming a seam 15 in which the back surface 11b of the surface 11 and the end surface 14b of the surface 14 are in close contact.

FIGS. 2A and 2B show a sheet metal 1A for forming such a pipe body 1. FIG. This sheet metal 1A
Are formed by punching from a metal sheet material as a raw material.

The concave portion 11c is open to the end surface 11d of the surface 11. Also, the inner width W1 of the concave portion 11c on the bottom wall 11e side.
Is the opening width W on the end face 11d side as shown in FIG.
The fitting recess 11g having an inclined surface 11f which is closer (narrower) to both widths of the bottom wall 11e toward the end face 11d side is formed.

The width W3 of the projection 14c along the longitudinal direction of the end face 14b is smaller than the opening width W2. Also,
Both ends in the longitudinal direction of the convex portion 14c protrude from the central portion. Further, as shown in FIG.
Is greater than the thickness H2 of the sheet metal 1A,
The depth H3 of the recess 11c is the same as the thickness H2 of the sheet metal 1A.

As a result, as shown in FIG. 1B, when the concave portion 11c and the convex portion 14c are engaged with each other,
Both end portions of the convex portion 14c protrude from the surface 11h. In FIG. 2, the same reference numerals are given to the constituent parts of the pipe body 1 after molding, and the description thereof will be omitted. Reference numerals P1, P2, and P3 in FIG. 2 are explanatory lines indicating bending positions by a press machine. The bending positions indicated by the explanation lines P1, P2 and P3 are designed in consideration of the amount of extension of the sheet metal 1A during press forming. Further, the sheet metal 1A is provided with a plurality of holes 11i for fixing to a machine (die) at the time of press working, which will be described later, on the surface 13 of the sheet metal 1A. The application range is processed according to the purpose of use of the pipe body 1 such as forming a screw hole 11j for fixing a panel or a part. At this time, the screw hole 11j may be a so-called stupid hole, or the hole 11i may be formed as a screw hole and also used as a hole for fixing the mold. Further, the positions and the numbers of the holes 11i and 11j are not limited, and the holes 11i and 11j may be formed after the pipe body is formed.

A case of forming a square pillar pipe body 1 using such a sheet metal 1A will be described with reference to FIG.

First, the sheet metal 1 is pressed by a known press machine.
Fold the explanation lines P1 to P3 of A (in the case of a quadrangular prism, the angle between the surface 11 and the surface 12 and the surface 12 and the surface 13 is 90
°, the angle between the surface 13 and the surface 14 is obtuse), FIG.
As shown in (1), a primary processed product 1B is formed.

Next, the primary processed product 1B is set on the lower die 21 of the press machine 20. At this time, the surface 13 of the primary processed product 1 </ b> B is fixed to the lower die 21 by the pressing mechanism 22 provided on the lower die 21.

From this state, as shown in FIG.
The upper mold 23 is moved down, and the edges 11a and 14a are brought close to each other while the press section 24 of the lower mold 21 is approached to each other by the upper mold 23, so that the concave portion 11c and the convex portion 14c are engaged with each other.
The next processed product 1C is obtained.

Further, as shown in FIG. 3C, the upper die 23 is further lowered from this state, so that the press part 25 of the upper die 23 is pressed while the approach position of the press part 24 of the lower die 21 is fixed. Both ends of the convex portion 14c are deformed while pressing the secondary workpiece 1C from a direction orthogonal to the pressing direction by the portion 24. This deformation is caused by the crushed part of the convex portion 14c entering the fitting concave portion 11g of the concave portion 11c. As a result, as shown in FIG.
And fit each other.

At this time, since the pressing by the press section 25 is in a direction orthogonal to the pressing direction by the press section 24, the shaping effect of the surfaces 11 to 14 can be obtained. Further, the fitting of the concave portion 11c and the convex portion 14c causes the surface 1
It is possible to obtain the pipe body 1 in a state where the back surface 11b of the first member 1 and the end surface 14b of the surface 14 are almost completely adhered to each other.

By the way, the second processed product 1C is not a substantially processed product because it is in the middle of the pressing process for forming the pipe 1 from the first processed product 1B.
The pressurization by the press section 24 is, of course, performed so as not to cause the deformation (crushing) of the pipe body 1 in order to obtain the above-described effect, and the degree is the thickness H of the sheet metal 1A.
It is set according to conditions such as 2 and material.

(Embodiment 2) In FIG.
Is a pipe body of the present invention. The pipe body 3 is formed in a square prism having four surfaces 31, 32, 33, and 34, and a surface 31 and a surface 3 that intersect each other (in this case, are orthogonal).
4 are aligned with the respective edges 31a and 34a,
A joint 35 is formed by bringing the end surface 34b of the edge portion 34a into contact with the back surface 31b of 1a.

4 (B) and 4 (C) are enlarged views of main portions of the edges 31a and 34a before the formation of the pipe body 3 is completed.
As shown in FIG. 5, a concave portion 31c (female side engaging portion) and a convex portion 34c (male side engaging portion) are formed so as to face each other in a direction crossing (orthogonal to) each other. This projection 34c
FIG. 4 is an enlarged view of a main part in a state where the formation of the pipe body 3 is completed.
As shown in (D) and (E), the deformation causes the recess 3.
1c, thereby forming a seam 35 in which the back surface 31b of the surface 31 and the end surface 34b of the surface 34 are in close contact.

FIGS. 5A and 5B show a sheet metal 3A for forming such a pipe body 3. FIG. This sheet metal 3A
Are formed by punching from a metal sheet material as a raw material.

The recess 31c is open to the end 31d of the surface 31. Also, the inner width W4 of the concave portion 31c on the side of the bottom wall 31e.
Is the opening width W on the end face 31d side, as shown in FIG.
5, a fitting recess 31g having an inclined surface 31f that is closer (narrower) to both widths of the bottom wall 31e toward the end face 31d side is formed.

The protrusion 34c has a width W6 along the longitudinal direction of the end face 34b smaller than the opening width W5. Also,
As shown in FIG. 5B, the maximum protrusion amount H4 of the convex portion 34c
The thickness H5 of the sheet metal 3A and the depth H6 of the recess 31c are substantially the same as the thickness H5 of the sheet metal 3A.

As a result, as shown in FIG. 4B, when the concave portion 31c and the convex portion 34c are engaged, the surface 3
The first surface 31h and the projection 34c are substantially flush. In FIG. 5, the same reference numerals are given to the components of the pipe body 3 after molding, and the description thereof will be omitted. In addition, the symbol P in FIG.
1, P2 and P3 are explanatory lines showing the bending positions by the press machine. The bending positions indicated by the explanation lines P1, P2 and P3 are designed in consideration of the amount of extension of the sheet metal 1A during press forming. In the sheet metal 3A, a plurality of holes 31i for fixing to a machine (die) at the time of press working, which will be described later, are formed in the surface 33, or the other surfaces 31, 32, and 34 are formed.
And the like, a screw hole 31j for fixing the body panel of the copying machine or fixing the parts is formed, and its application range is processed according to the purpose of use of the pipe body 3. At this time, screw hole 3
1j may be a so-called stupid hole, or the hole 31i may be a screw hole to be used also as a hole for fixing a mold. Further, the positions and the numbers of the holes 31i and 31j are not limited, and may be formed after the pipe body is formed.

A case of forming a square pillar pipe body 3 using such a sheet metal 3A will be described with reference to FIG.

First, the sheet metal 3 is pressed by a known press machine.
Fold the explanation lines P1 to P3 of A (in the case of a square prism, the angle between the surface 31 and the surface 32 and the angle between the surface 32 and the surface 33 is 90
°, the angle between the surface 33 and the surface 34 is an obtuse angle), FIG.
As shown in (1), a primary processed product 3B is formed.

Next, the primary processed product 3B is set on the lower die 41 of the press machine 40. At this time, the surface 33 of the primary processed product 3 </ b> B is fixed to the lower mold 41 by the pressing mechanism 42 provided on the lower mold 41.

From this state, as shown in FIG.
The upper mold 43 is lowered, and the press sections 44 of the lower mold 41 are moved closer to each other by the upper mold 43 so that the edges 31a and 34a approach each other, so that the concave portion 31c and the convex portion 34c are engaged with each other.
The next processed product 3C is obtained.

Further, as shown in FIG. 6C, the upper die 43 is further lowered from this state, so that the press part 45 of the upper die 43 is pressed while the approach position of the press part 44 of the lower die 41 is fixed. The secondary processing product 3C is pressed from a direction orthogonal to the pressing direction by the part 44.

At this time, as shown in FIG. 7, a punch portion 46 is projected from the press portion 45 at a position opposed to the convex portion 34c, and the convex portion 34c is deformed by the punch portion 46. As a result, a part of the convex portion 34c is
4c as a result, the fitting recess 31g of FIG.
As shown in (E), the concave portion 31c and the convex portion 34c are fitted.

At this time, since the pressing by the pressing section 45 is in a direction orthogonal to the pressing direction by the pressing section 44, the shaping effect of the surfaces 31 to 34 can be obtained. Further, the fitting of the concave portion 31c and the convex portion 34c causes the surface 3
It is possible to obtain the pipe body 3 in a state where the back surface 31b of the first surface 31 and the end surface 34b of the surface 34 are almost completely adhered.

By the way, the secondary processed product 3C is not a substantially processed product because it is in the middle of the pressing process for processing the pipe 3 from the primary processed product 3B.
Pressing by the press section 44 is, of course, performed to such an extent that the pipe body 3 is not deformed (crushed) in order to obtain the above-mentioned effect, and the degree is the thickness H of the sheet metal 3A.
5 is set according to conditions such as the material and the like.

[0052]

As described above, according to the structure of the first aspect, the springback at the time of press forming is absorbed by the fitting which is prevented from coming off due to the deformation of the male side engaging portion, and each edge is formed. Since the parts are in close contact with each other, the seam can be stably brought into close contact with each other while being formed only by press molding without performing welding during mass production.

According to the second aspect of the present invention, it is possible to provide a pipe body sheet metal for providing a pipe body having a pair of edges closely contacted by a predetermined pressing step.
Transportation and the like during distribution can be easily performed.

According to the third aspect of the present invention, since the projection of the male side engaging portion from the end face is larger than the thickness of the sheet metal, the male side engaging portion can be easily deformed by the press machine. be able to.

According to the fourth aspect of the present invention, since the projecting amount of the male engaging portion from the end face is substantially the same as the thickness of the sheet metal, the male engaging portion is deformed by the press machine after the deformation. The tip of the side engaging portion is unlikely to protrude from the surface, and the flatness of the surface can be easily ensured.

According to the fifth aspect of the present invention, the male side engaging portion can be easily engaged with the female side engaging portion.

According to the sixth aspect, when the male-side engaging portion is deformed, the fitting with the female-side engaging portion can be performed easily and reliably.

According to the seventh and eighth aspects, it is possible to form a pipe body in which seams are in close contact only by a simple pressing step, and to press the fitting by deformation of the female side engaging portion. Can be done in the process.

[Brief description of the drawings]

1A and 1B show a pipe body according to a first embodiment of the present invention, wherein FIG. 1A is an external perspective view of the pipe body, FIG. 1B is an enlarged view of a main part before formation of the pipe body is completed, and FIG. It is an enlarged view of the principal part in the state of completion of body formation.

FIG. 2 is a plan view of the sheet metal according to the first embodiment of the present invention.

3A and 3B are time-series explanatory diagrams according to Embodiment 1 of the present invention, in which FIG. 3A is a cross-sectional view of a press machine with a primary processed product set, and FIG. FIG. 2C is a cross-sectional view of the press machine, and FIG.

4A and 4B show a pipe body according to a second embodiment of the present invention, wherein FIG. 4A is an external perspective view of the pipe body, FIG. 4B is an enlarged view of a main part before the formation of the pipe body is completed, and FIG. It is an enlarged view of the principal part in the state of completion of body formation.

FIG. 5 is a plan view of a sheet metal according to Embodiment 2 of the present invention.

6A and 6B are time-series explanatory diagrams according to Embodiment 2 of the present invention, wherein FIG. 6A is a cross-sectional view of a press machine with a primary processed product set, and FIG. FIG. 2C is a cross-sectional view of the press machine, and FIG.

FIG. 7 is a partially enlarged view of a mold used when forming a pipe body according to Embodiment 2 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pipe body 11 ... Surface 11a ... Edge 11b ... Back surface 11c ... Concave part (female side engaging part) 11d ... End surface 11e ... Bottom wall 11f ... Inclined surface 11g ... Fitting concave part 12 ... Surface 13 ... Surface 14 ... Surface 14a ... Edge 14b ... End face 14c ... Protrusion (male side engaging part) 15 ... Joint 1A ... Sheet metal 1B ... Primary processed product 1C ... Secondary processed product

Claims (8)

[Claims] 1. A pipe body having a closed cross-section formed by forming a seam between an end face of one edge of a face that intersects and a back face of the other edge, protruding from an end face of the one edge. The male-side engaging portion engages with the female-side engaging portion formed on the other edge portion, and the female-side engaging portion is prevented from falling off by deformation of the male-side engaging portion. A pipe body wherein the edges are in close contact with each other in a fitted state. 2. A deformable male-side engaging portion is projected from an end surface of one edge of a rectangular sheet metal, and is engageable with the male-side engaging portion at an edge parallel to the one edge. A metal plate for a pipe body, comprising: a female engaging portion. 3. The sheet metal for a pipe body according to claim 2, wherein an amount of protrusion of the male side engaging portion from the end face is larger than a thickness of the rectangular sheet metal. 4. The sheet metal for a pipe body according to claim 2, wherein an amount of protrusion of the male side engaging portion from the end face is substantially equal to a thickness of the rectangular sheet metal. 5. The female-side engaging portion is a concave portion opened to the end face of the other edge portion and is set wider than the width of the male-side engaging portion. The sheet metal for a pipe body according to claim 2. 6. The sheet metal for a pipe body according to claim 5, wherein an opening diameter of the recess near the open end is smaller than an opening diameter near the bottom edge. 7. A plurality of surfaces are formed by bending the sheet metal for a pipe body according to any one of claims 2 to 6 along a pair of parallel edges, and the plurality of surfaces are parallel. Surfaces having a pair of parallel edges intersect and the pair of parallel edges are opposed to each other in a spaced state, and the male side engaging portion protruding from one end face of the parallel edge is attached to the other edge. A method for forming a pipe body, comprising: forming a seam by engaging with the formed female side engagement, and deforming the male side engagement portion to fit the female side engagement portion. 8. A plurality of surfaces are formed by bending the sheet metal for a pipe body according to claim 2 along a pair of parallel edges, and said plurality of surfaces are parallel. A first step in which surfaces having a pair of parallel edges intersect and the pair of parallel edges are opposed to each other in a spaced state to obtain a first workpiece, and the first edge is protruded from one end surface of the parallel edges. A second step of engaging the male-side engaging portion with the female-side engaging portion formed on the other edge to obtain a second processed product having a seam; and deforming the male-side engaging portion to obtain the second processed product. And a third step of fitting the female body into the female-side engaging portion to obtain a pipe body.