WO2018139443A1

WO2018139443A1 - Manufacturing method for tubular member

Info

Publication number: WO2018139443A1
Application number: PCT/JP2018/001955
Authority: WO
Inventors: 剛大真鍋
Original assignee: フタバ産業株式会社
Priority date: 2017-01-24
Filing date: 2018-01-23
Publication date: 2018-08-02
Also published as: JP2018118269A; JP6756633B2

Abstract

In this manufacturing method for a tubular member, by pressing side surfaces of a tubular member from outside, the shape of a cross-section that is perpendicular to a direction in which the tubular member extends is molded into an oblong shape that extends in a predetermined direction. An interior mold, said interior mold coming into contact with an inner surface of the tubular member that is being pressed such that the cross-section becomes the oblong shape, is inserted into an interior of the tubular member, and the interior mold is slid from one end of the tubular member to the other end. At such time, when the interior mold is viewed in the sliding direction, one or a plurality of contact regions where the inner surface of the tubular member and the interior mold come into contact are in a condition of having spread to the entire area of the inner surface.

Description

Method for manufacturing cylindrical member

Cross-reference of related applications

This international application claims priority based on Japanese Patent Application No. 2017-010378 filed with the Japan Patent Office on January 24, 2017, and is based on Japanese Patent Application No. 2017-010378. The entire contents are incorporated by reference into this international application.

The present disclosure relates to a method for manufacturing a cylindrical member.

A flat muffler is known. The side surface of the outer shell member of such a muffler is constituted by a metallic cylindrical member having a flat cross section. Here, Patent Document 1 discloses a method for manufacturing such a cylindrical member. In the manufacturing method, the cross section of the cylindrical cylindrical member is formed into an elliptical shape by press molding.

Japanese Patent No. 5745785

However, after press molding, the cylindrical member having an elliptical cross section may be deformed by the springback. Specifically, for example, a portion of the tubular member that is flattened by press molding may be bent again due to the spring back. For this reason, it is necessary to perform press molding in consideration of the influence of the spring back, and the operation of molding the cylindrical member has been difficult.

It is desirable to facilitate the forming of the cylindrical member in the process of manufacturing the cylindrical member.

In the manufacturing method of the cylindrical member which is one side of this indication, the shape of the section orthogonal to the direction where a cylindrical member extends is extended in the predetermined direction by pressing the side of a cylindrical member from the outside. Molded into a longitudinal shape. In addition, an internal mold that contacts the inner surface of the cylindrical member is inserted into the cylindrical member that is pressed so that the cross-section has a longitudinal shape, and the internal mold extends from one end to the other end of the cylindrical member. To be slid. When the inner mold slides from the one end to the other end of the inner surface of the cylindrical member, when the inner mold is viewed in the sliding direction, the inner mold is in contact with one or more contact areas. Is configured to spread over the entire inner surface.

According to such a configuration, a load is applied to the inner surface by sliding the inner surface of the cylindrical member pressed to make the cross section of the section into a longitudinal shape with the internal mold. Thereby, when the pressing of the cylindrical member is released, the cylindrical member can be prevented from being deformed by the springback. Therefore, in the process of manufacturing the cylindrical member, the cylindrical member can be easily formed.

Note that the cylindrical member may extend linearly.
According to such a configuration, it becomes easy to form a cylindrical member extending linearly.
Moreover, the shape of the cross section of the cylindrical member before being pressed so that the cross section becomes a longitudinal shape may be circular or substantially circular.

According to such a configuration, the cylindrical member can be easily formed.
Further, the internal mold may have a plurality of divided portions. The plurality of divided portions are configured such that one or more contact areas are formed by the outer surface of each divided portion, and each divided portion has a relative position with respect to the other one or more divided portions. It may be configured to be adjustable.

According to such a configuration, the position of the outer surface of each divided portion can be adjusted, thereby adjusting the position or the like of one or a plurality of contact areas that contact the inner surface of the cylindrical member in the internal mold. For this reason, for example, even when the shape of the outer surface of the divided portion is deformed due to wear, a state where one or a plurality of contact regions are formed in the internal mold by adjusting the position of the outer surface of the divided portion Can be maintained.

The cylindrical member may be mounted on the vehicle.
According to such a configuration, it becomes easy to form a cylindrical member mounted on the vehicle.

FIG. 1A is a perspective view of a muffler, and FIG. 1B is a perspective view of a first tubular member in the present embodiment. 1C and 1D are explanatory views showing an end portion of a metal plate arranged in a state where the first cylindrical member is formed in the arrangement step in the present embodiment. FIG. 1E is an explanatory view showing an end portion of the second tubular member after welding in the present embodiment. FIG. 2A is an explanatory diagram illustrating a state in which the second cylindrical member is pressed by the rotating body and the lower member in the pressing step of the present embodiment. FIG. 2B is an enlarged view of a portion pressed by the rotating body and the lower member in the second cylindrical member in the pressing step of the present embodiment. Drawing 2C is an explanatory view showing signs that the 2nd cylindrical member is pressed at the forming step of this embodiment. 3A is a front view of the internal mold used in the passing step of the present embodiment, FIGS. 3B and 3C are side views of the internal mold, and FIGS. 3D and 3E are top views of the internal mold. . FIG. 4 is an explanatory diagram showing a state in which the inner surface of the third cylindrical member is slid by the internal mold in the passing step of the present embodiment.

DESCRIPTION OF SYMBOLS 2 ... Metal plate, 2a, 2b ... Edge part, 2c ... Overlapping part, 11 ... Side part, 20 ... 1st cylindrical member, 21 ... 2nd cylindrical member, 22 ... 3rd cylindrical member, 30 ... Rotating body 30a, upper contact area, 31 lower member, 31a lower contact area, 40 first outer mold, 41 second outer mold, 50 inner mold, and 51 to 53 divided sections.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Embodiments of the present disclosure are not limited to the following embodiments, and various forms can be adopted as long as they belong to the technical scope of the present disclosure.

[Description of manufacturing method]
In the manufacturing method of the present embodiment, a cylindrical member that extends linearly in a predetermined extension direction is manufactured. The cylindrical member has a longitudinal shape in which a cross section perpendicular to the extending direction (hereinafter simply referred to as a cross section) extends in the longitudinal direction. More specifically, the longitudinal shape means a shape in which the length in the longitudinal direction is longer than the length in the short direction. In addition, a transversal direction means the direction orthogonal to a longitudinal direction. Specifically, the longitudinal shape may be, for example, an elliptical shape or a rectangular shape. The cylindrical member is made of a metal such as stainless steel, for example.

In the manufacturing method, as an example, as shown in FIG. 1A, the side surface portion 11 of the outer shell member 10 of the muffler 1 of the vehicle is manufactured. The outer shell member 10 is a plate-like member that separates the inside and the outside of the muffler 1. The outer shell member 10 has two bottom surface portions 12 and side surface portions 11. Each bottom surface portion 12 has a longitudinal shape. Moreover, the side part 11 is a cylindrical member whose cross section mentioned above is a longitudinal shape (more specifically, elliptical shape).

In addition, the cylindrical member used for various uses may be manufactured with the manufacturing method of this embodiment. Specifically, for example, a pipe or a cylindrical member included in a housing for storing a predetermined device may be manufactured. Moreover, these members may be mounted on a vehicle.

The manufacturing method according to the present embodiment includes an arrangement step, a welding step, a pressing step, a forming step, and a passing step.
In the arranging step, one or a plurality of metal plates 2 are arranged in a state where the first cylindrical member 20 shown in FIG. 1B is formed. The first tubular member 20 extends linearly in the extending direction 20a. Moreover, the 1st cylindrical member 20 has fixed thickness. That is, the size and shape of each cross section of the first cylindrical member 20 are the same. Here, the shape of the cross section of the first cylindrical member 20 is referred to as an original shape. As an example of the original shape, a circular shape or a substantially circular shape can be given. That is, the 1st cylindrical member 20 is cylindrical. The original shape may be a shape other than a circle or a substantially circle. Specifically, the original shape may be a polygonal shape, for example. Further, the first cylindrical member 20 may be a cylindrical member that extends non-linearly. In other words, the first cylindrical member 20 may extend along a curved or bent path, for example.

And each

edge part

2a, 2b in the 1 or several metal plate 2 which forms the 1st cylindrical member 20 is extended along the extending | stretching direction 20a. Moreover, each

edge part

2a, 2b is extended over the other end from the one end of the 1st cylindrical member 20, as an example.

More specifically, in the arranging step, as shown in FIGS. 1C and 1D, as an example, the first cylindrical member 20 is formed by the metal plate 2 by curving one rectangular metal plate 2 into a cylindrical shape. You may do it. Moreover, the two

edge parts

2a and 2b which make two opposite sides in this metal plate 2 may overlap. Hereinafter, a portion where these

edge portions

2a and 2b overlap is referred to as an overlapping portion 2c.

Furthermore, as shown in FIG. 1C, the metal plates 2 forming the first cylindrical member 20 may be arranged in a single layer. Moreover, as shown to FIG. 1D, this metal plate 2 may be arrange | positioned in the state which overlapped twice. Moreover, this metal plate 2 may be arrange | positioned in the state which overlapped more than triple.

In addition, in the arrangement step, for example, a plurality of metal plates curved in a groove shape may be arranged in a state in which the first cylindrical member 20 is formed. Even in such a case, each metal plate may be similarly provided with an overlapping portion overlapping with an edge of another metal plate at the edge thereof.

Next, in the welding step, the plurality of facing

edges

2a and 2b in the one or more metal plates 2 forming the first cylindrical member 20 are welded along the plurality of

edges

2a and 2b. The Specifically, the overlapping portion 2c, which is a portion where the plurality of

edge portions

2a and 2b overlap, is welded. Thereby, the some

edge part

2a, 2b is joined, and the 2nd cylindrical member 21 is produced | generated.

More specifically, the portions located on both or one of the outer side and the inner side of the first cylindrical member 20 in the overlapping portion 2c may be welded. Further, for example, the overlapping portion 2c may be welded by any one of seam welding, spot welding, arc welding, plasma welding, and TIG welding. In addition, the overlapping portion 2c may be welded by using a plurality of these welding methods in combination. Further, the overlapping portion 2c may be welded by one or a plurality of welding methods including seam welding.

Here, as a result of welding, the portion of the second cylindrical member 21 including the overlapping portion 2c becomes high temperature. For this reason, a residual stress is generated in a portion including the overlapping portion 2 c in the second cylindrical member 21. For this reason, the second cylindrical member 21 has a cross-sectional shape different from the original shape. Specifically, for example, when the original shape is circular or substantially circular, as shown in FIG. 1E, the cross section of the second cylindrical member 21 loses the rounded portions 2c and portions on both sides thereof.

Therefore, in the subsequent pressing step, a portion (hereinafter referred to as a pressing target portion) including the overlapping portion 2c in the second cylindrical member 21 is pressed. Note that the portion to be pressed may include a portion that is estimated to have residual stress in the second tubular member 21. Further, the pressing target portion may include a portion deformed by welding in the second cylindrical member 21. At this time, the pressing target portion is sandwiched between two members from the inside and the outside of the second cylindrical member 21. As an example, as illustrated in FIGS. 2A and 2B, the pressing target portion is pressed by the rotating body 30 and the lower member 31.

The lower member 31 is an elongated member extending in the extending direction, and has a lower contact region 31a. The lower contact region 31 a is provided on the upper outer surface of the lower member 31. The lower contact region 31a is a belt-like region that extends linearly in the extending direction and has a constant or substantially constant width.

Further, the lower contact region 31a is curved so that the center in the width direction protrudes. That is, the portion corresponding to the lower contact region 31a in the cross section orthogonal to the extending direction of the lower member 31 has an arc shape. Moreover, each cross section orthogonal to the extending | stretching direction of the lower side contact area | region 31a is the same shape from one end to the other end. The degree of curvature of the cross section may be the same as or substantially the same as the degree of curvature of the overlapping section in the cross section of the first tubular member 20. The overlapping section is a section including a portion where the overlapping portion 2 c is located in the cross section of the first tubular member 20.

Also, the lower member 31 is disposed inside the second cylindrical member 21. At this time, the lower member 31 is located below the pressing target portion and extends from one end of the pressing target portion to the other end. Further, the lower contact area 31a faces the pressing target portion. At this time, the lower contact region 31a may contact all or a part of the pressing target portion.

On the other hand, the rotating body 30 is a columnar member extending linearly in the axial direction. The side surface of the rotating body 30 is curved so that the center in the axial direction is deepest. That is, the diameter of a circle having a cross section perpendicular to the axial direction in the rotating body 30 is the shortest at the center in the axial direction and becomes longer toward the end in the axial direction.

Here, a region including the center in the axial direction on the side surface of the rotating body 30 is referred to as an upper contact region 30a. In addition, in the cross section perpendicular to the axial perpendicular line of the rotator 30 and including the center line of the rotator 30, the portion corresponding to the upper contact region 30a is arcuate. The center line is a straight line that passes through the center of each bottom surface of the rotating body 30 and extends in the axial direction. The degree of curvature of the arc-shaped portion is the same or substantially the same as the degree of curvature of the overlapping section described above.

Then, the rotating body 30 presses the pressing target portion of the second cylindrical member 21 disposed on the lower member 31 from the outside of the second cylindrical member 21. At this time, the upper contact region 30 a of the rotating body 30 is in a state of contacting the pressing target portion from the outside of the second cylindrical member 21. At this time, the pressing target portion is sandwiched between the upper contact area 30 a of the rotating body 30 and the lower contact area 31 a of the lower member 31. The rotating body 30 rolls on the pressing target portion from one end to the other end of the second cylindrical member 21 while pressing the pressing target portion.

Further, as described above, the degree of curvature of the upper contact area 30a and the lower contact area 31a is the same or substantially the same as the degree of curvature of the overlapping section described above. For this reason, by pressing with the rotating body 30, the degree of bending of the pressing target portion in the second cylindrical member 21 is the degree of bending in the overlapping section described above (in other words, the degree of bending of the original cross section). To be the same or substantially the same. That is, the second tubular member 21 is prompted to have the original cross section.

In addition to this, the pressing target portion of the second tubular member 21 may be pressed by a member other than the rotating body 30. Specifically, for example, the pressing target portion may be pressed by sandwiching the pressing target portion of the second tubular member 21 once or a plurality of times by an upper member and a lower member (not shown). Here, the area | region which contact | abuts to the press object part in each of an upper side member and a lower side member is made into a contact area | region. The contact area may have a shape corresponding to the original shape. Then, the second tubular member 21 may be urged so that the cross section of the second tubular member 21 becomes the original shape by pressing with the upper member and the lower member. Further, the pressing target portion may be pressed by the rotating body 30 and the lower member 31 or the upper member and the lower member without prompting the second cylindrical member 21 to have the original cross section. Further, in the pressing step, the cross section of the second cylindrical member 21 may be urged to have a shape other than the original shape by pressing.

Next, in the forming step, the second tubular member 21 is formed by pressing the second tubular member 21 from the outside so that the cross section has the above-described longitudinal shape. In other words, the longitudinal shape is a shape longer than the original shape.

As shown in FIG. 2C, in the molding step, as an example, the first external mold 40 and the second external mold 41 are arranged in a vertically aligned state. Further, the second cylindrical member 21 is disposed on the second external mold 41 located on the lower side. And the 2nd cylindrical member 21 is pressed by moving the 1st external type | mold 40 below and pinching the 2nd cylindrical member 21 with the 1st external type | mold 40 and the 2nd external type | mold 41. FIG. Thereby, the cross section of the 2nd cylindrical member 21 becomes a longitudinal shape. Hereinafter, the second cylindrical member 21 having a longitudinal section is referred to as a third cylindrical member 22.

Here, in the third cylindrical member 22, two portions extending along the longitudinal direction are defined as a longitudinal portion 22a. Further, in the third cylindrical member 22, two portions positioned at the end in the longitudinal direction are referred to as a short portion 22b. In other words, the longitudinal portion 22a is a portion of the third cylindrical member 22 that has a relatively high degree of elongation due to the pressing of the molding step. In the 3rd cylindrical member 22, the duplication part 2c is located in the longitudinal part 22a as an example. More specifically, the overlapping portion 2c is located at the end of the upper longitudinal portion 22a. In addition, the overlapping part 2c may be located in the short part 22b. That is, in the forming step, the overlapping portion 2c of the second cylindrical member 21 disposed on the second external mold 41 is in a stage before pressing so that the overlapping portion 2c is in a predetermined position when pressed. The position of is adjusted.

However, the third cylindrical member 22 is made of metal. For this reason, after the pressing in the molding step, if the first external die 40 is moved upward to release the pressing, the third tubular member 22 may be spring-backed. In other words, the third cylindrical member 22 that has been released from the pressure may be bent so that, for example, the longitudinal portion 22a bulges outward due to elastic recovery.

Therefore, in the subsequent passing step, the internal mold 50 shown in FIGS. 3A to 3E is inserted into the third cylindrical member 22 pressed by the first and second

external molds

40 and 41. The inner mold 50 is configured such that a part of its outer surface comes into contact with the inner surface of the third cylindrical member 22. One or a plurality of contact regions where the outer surface of the internal mold 50 and the inner surface of the third cylindrical member 22 contact each other are in a state of making a round of the inner surface (hereinafter referred to as a contact state).

More specifically, a closed path (in other words, a loop-shaped path) along the outer surface of the internal mold 50 is defined as a circulation path. When the internal mold 50 is inserted into the third cylindrical member 22, the entire circumference of the circuit path extends along the cross section of the third cylindrical member 22. One or a plurality of contact areas are arranged along the circulation path. That is, at least one contact region 50d exists on the circulation path and / or on the side of the circulation path in the entire circulation path.

In the passing step, as shown in FIG. 4, the inner die 50 moves from one end of the third cylindrical member 22 to the other end while maintaining the contact state. More specifically, the internal mold 50 is inserted into the third cylindrical member 22 from one end of the third cylindrical member 22. The internal mold 50 moves to the other end of the third cylindrical member 22, and then moves to one end of the third cylindrical member 22. By this movement, the inner surface of the third cylindrical member 22 is slid by the internal mold 50.

As shown in FIGS. 3A to 3D, the internal mold 50 includes two

division parts

51 and 52 as an example. Each divided portion is an elongated portion extending in the longitudinal direction 50a. One split portion 51 is attached to one end of the rod-like portion 55. The rod-shaped part 55 is used for moving the internal mold 50 in the passing step.

Further, the two divided

parts

51 and 52 are coupled by a plurality of screws 56 or the like. The internal mold 50 is configured as a combined body of the divided

portions

51 and 52, and when the divided

portions

51 and 52 are combined, the outer surfaces of the divided portions are in contact with each other. And when the some screw | thread 56 is loosened, each division part can adjust the relative position with respect to another division part. Specifically, when the plurality of screws 56 are loosened, each divided portion is movable in the longitudinal direction 50a as an example. And when the some screw | thread 56 is tightened, the position of each division | segmentation part is fixed.

Here, the outer edge when the two divided portions 51 and 52 (in other words, the inner mold 50) are viewed in the sliding direction 50b is referred to as a contact outer edge 50c. The sliding direction 50b corresponds to the traveling direction of the internal mold 50 when the internal mold 50 slides on the inner surface of the third cylindrical member 22 in the passing step. The contact outer edge 50c overlaps with the above-described circulation path. The two divided

portions

51 and 52 are configured such that the contact outer edge 50 c has the same or substantially the same shape as the cross section of the third cylindrical member 22. When the inner die 50 comes into contact, a contact region 50d that contacts the inner surface of the third cylindrical member 22 is formed along the contact outer edge 50c. The contact region 50d is in a state of making a round on the inner surface of the third cylindrical member 22. In other words, when the internal die 50 is viewed in the sliding direction 50b when the contact state is reached, the contact region 50d in the internal die 50 is in a state of spreading over the entire inner surface of the third cylindrical member 22. .

In addition, the two

division parts

51 and 52 may be combined with a gap. In this case, two separated contact areas exist along the circulation path on the outer surface of the internal die 50. When the inner die 50 is viewed in the sliding direction 50 b when the contact state is reached, a plurality of contact regions in the inner die 50 are spread over the entire inner surface of the third cylindrical member 22.

Also, the size and shape of the contact outer edge 50c (in other words, the size and shape of the circulation path) can be changed by changing the relative positions of the respective divided portions. Thereby, the size and shape of the contact area 50d change.

In addition, you may comprise an internal type | mold by one site | part. A similar contact area may be provided on the outer surface of the internal mold.
Moreover, you may comprise an internal type | mold with three or more division parts. That is, as shown in FIG. 3E, the internal mold 50 may have three divided parts 51 to 53 as an example. Each divided portion is an elongated portion extending in the longitudinal direction 50a. The dividing portion 53 is attached to one end of the rod-like portion 55. In such a case, the contact area 50d may be provided on the outer surface of the internal mold 50 in the same manner. Further, each of the two divided

portions

51 and 52 may be configured to be coupled to the divided portion 53 by a plurality of screws 56, and the relative positions of the divided portions may be adjusted in the same manner. Similarly, the divided portions may be combined with a gap.

[effect]
(1) According to the embodiment, the pressed portion of the second cylindrical member 21 pressed in the pressing step includes a welded portion. By the pressing step, the residual stress generated in the second cylindrical member 21 by welding is removed. For this reason, when shape | molding the 2nd cylindrical member 21 in another shape, it can suppress that buckling etc. arise, for example. Therefore, in the process of manufacturing the cylindrical member, the cylindrical member can be easily formed.

(2) Further, in the pressing step, the second tubular member 21 is urged so that the cross section has the original shape. For this reason, it becomes easy to shape | mold the 2nd cylindrical member 21 in another shape.
(3) Moreover, in an arrangement | positioning step, the 1 or several metal plate 2 is arrange | positioned in the state in which the 1st cylindrical member 20 was formed. The first tubular member 20 extends linearly along the extending direction 20a. For this reason, it becomes easy to form a cylindrical member extending linearly.

(4) Moreover, the cross section of the 1st cylindrical member 20 is circular or substantially circular. For this reason, it becomes easy to form a cylindrical member.
(5) In the welding step, the welding of the one or more metal plates 2 is performed using at least one of seam welding, spot welding, arc welding, plasma welding, and TIG welding.

When it is welded by these welding methods, it is considered that one or a plurality of metal plates 2 are likely to become high temperature. That is, there is a possibility that more residual stress is generated in the second tubular member 21 generated by welding. For this reason, it becomes possible to remove a residual stress effectively by the press by a press step.

(6) Further, in the pressing step, the pressing target portion of the second cylindrical member 21 is pressed by rolling the rotating body 30. Thereby, the part including the part by which the welding in the 2nd cylindrical member 21 was made can be pressed effectively.

(7) Moreover, in the manufacturing method of the said embodiment, the cylindrical member mounted in vehicles, such as the side part 11 in the outer shell member 10 of the muffler 1, for example, is manufactured. For this reason, it becomes easy to mold the cylindrical member mounted on the vehicle.

(8) Further, in the passing step, a load is applied to the inner surface by sliding the inner surface of the third cylindrical member 22 pressed in order to make the cross section into a longitudinal shape by the internal mold 50. Thereby, when the press of the 3rd cylindrical member 22 is cancelled | released, it can suppress that the 3rd cylindrical member 22 deform | transforms by a springback. Therefore, the cylindrical member can be easily formed.

(9) Moreover, the internal mold | type 50 is comprised as the coupling body of a some division part. And each division part can adjust a relative position to other division parts.
For this reason, the position of the outer surface of each division part can be adjusted, and thereby the position or the like of one or a plurality of contact areas where the internal mold 50 contacts the inner surface of the third cylindrical member 22 is adjusted. Therefore, for example, even when the shape of the outer surface of the divided portion is deformed due to wear, a state where one or a plurality of contact regions are formed in the internal mold 50 by adjusting the position of the outer surface of the divided portion. Can be maintained. Moreover, it becomes possible to use the internal mold | type 50 for sliding the inner surface of the cylindrical member of various shapes similarly.

[Other Embodiments]
(1) In the above embodiment, the first to third cylindrical members 20 to 22 have the same cross-sectional size and shape. However, the first to third cylindrical members 20 to 22 may not have the same cross-sectional size and / or shape. In the passing step, for example, the internal die 50 may be moved from one end to the other end of the third cylindrical member 22 while maintaining the above-described contact state by changing the orientation of the internal die. .

(2) In the molding step of the above embodiment, the second cylindrical member 21 is molded into the third cylindrical member 22 having a longitudinal section. However, the second cylindrical member 21 may be formed in other shapes. Specifically, for example, the second cylindrical member 21 may be formed into a cylindrical member having a polygonal cross section, or may be formed into a curved or bent cylindrical member. Moreover, the 2nd cylindrical member 21 may be shape | molded, for example so that the duplication part 2c may extend in the direction (For example, the direction orthogonal or substantially orthogonal) which cross | intersects the expansion | extension direction 20a.

(3) The functions of one component in the above embodiment may be shared by a plurality of components, or the functions of a plurality of components may be exhibited by one component. Moreover, you may abbreviate | omit a part of structure of the said embodiment as long as a subject can be solved. In addition, all the aspects included in the technical idea specified from the wording described in the claims are embodiments of the present disclosure.

Claims

A method of manufacturing a tubular member,
By pressing the side surface of the cylindrical member from the outside, the shape of the cross section orthogonal to the direction in which the cylindrical member extends is formed into a longitudinal shape extending in a predetermined direction,
An internal mold that contacts the inner surface of the cylindrical member is inserted into the cylindrical member that is pressed so that the cross section has the longitudinal shape, and the internal mold is moved from one end of the cylindrical member to the other. Slide to the end,
When the internal mold slides the inner surface of the cylindrical member from one end to the other end, when the internal mold is viewed in the sliding direction, the inner mold is in contact with the inner mold or the inner mold. A method for manufacturing a cylindrical member, wherein the contact region is configured to be in a state of spreading over the entire inner surface.
In the manufacturing method of the cylindrical member described in Claim 1,
The said cylindrical member is a manufacturing method of the cylindrical member extended linearly.
In the manufacturing method of the cylindrical member described in Claim 1 or Claim 2,
The shape of the said cross section of the said cylindrical member before pressing so that the said cross section may become the said longitudinal shape is circular or substantially circular. The manufacturing method of a cylindrical member.
In the manufacturing method of the cylindrical member given in any 1 paragraph of Claims 1-3,
The internal mold has a plurality of divided portions,
The plurality of divided portions are configured such that the one or more contact regions are formed by an outer surface of each divided portion, and each divided portion has a relative position with respect to the other one or more divided portions. The manufacturing method of the cylindrical member comprised so that adjustment is possible.
In the manufacturing method of the cylindrical member given in any 1 paragraph of Claims 1-4,
The said cylindrical member is a manufacturing method of the cylindrical member mounted in a vehicle.