Method for manufacturing pipe

Patent metadata

Field	Value
Publication number	US-11534813-B2
Application number	US-202117140201-A
Country	US
Kind code	B2
Filing date	Jan 4, 2021
Priority date	Feb 12, 2020
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

A method for manufacturing a pipe includes: press-forming a plate member into a U shape; and press-forming the plate member formed into the U shape into an O shape. The pipe includes a pipe body and a tapered part tilted radially inward and protruding from one end of the pipe body. Before the plate member is press-formed into the U shape, a boundary between a portion of the plate member corresponding to the pipe body and a portion of the plate member corresponding to the tapered part is pressed from a surface of the plate member corresponding to an inner peripheral surface of the pipe to bend the portion of the plate member corresponding to the tapered part toward the surface of the plate member corresponding to the inner peripheral surface of the pipe.

First claim

What is claimed is:

1. A method for manufacturing a pipe having a pipe body and a tapered part tilted radially inward and protruding from one end of the pipe body, the method comprising:
press-forming a plate member into a U shape;
press-forming a groove into a boundary between a portion of the plate member corresponding to the pipe body and a portion of the plate member corresponding to the tapered part at a surface of the plate member corresponding to an inner peripheral surface of the pipe to bend a portion of the plate member corresponding to the tapered part toward the surface of the plate member corresponding to the inner peripheral surface of the pipe; and
press-forming the plate member formed into the U shape into an O shape.

2. The method according to claim 1 , wherein the groove has a curved section.

3. The method according to claim 1 , wherein when the boundary is pressed, the groove is formed while bending a middle part of the portion corresponding to the pipe body into a U shape.

4. The method according to claim 1 , wherein the groove is formed by pressing the boundary with a punch having a ridge corresponding to the groove.

5. The method according to claim 4 , wherein a die on which the plate member is placed when the boundary is pressed is provided with a die groove at a position corresponding to the ridge of the punch.

6. The method according to claim 4 , wherein:
a die on which the plate member is placed when the boundary is pressed is a die divided by a clearance that is predetermined; and
the clearance is located at a position corresponding to the ridge of the punch.

7. The method according to claim 4 , wherein the ridge of the punch has a curved section.

8. The method according to claim 1 , wherein a radius of curvature of the portion corresponding to the pipe body after the plate member is press-formed into the U shape is smaller than a radius of curvature of the portion corresponding to the pipe body after the plate member formed into the U shape is press-formed into the O shape.

Assignees

• Toyota Motor Co Ltd

Inventors

• Asano Masahiko
• Ukai Yoshihiko

Classifications

• B21C37/156

  Making tubes with wall irregularities (B21C37/20, B21C37/22 take precedence) · CPC title

• B21D5/015 Primary

  for making tubes · CPC title

• B21D51/02

  characterised by the structure of the objects {(B21D51/26 takes precedence)} · CPC title

• B21C37/0815

  without continuous longitudinal movement of the sheet during the bending operation · CPC title

• B21C37/15 Primary

  Making tubes of special shape; Making {tube} fittings {(B21C37/0803, B21C37/104, B21C37/124 take precedence)} · CPC title