Title:
MANUFACTURING METHOD, CYLINDER, CIRCUIT BREAKER AND DISTRIBUTION PANEL
Document Type and Number:
Japanese Patent JP2022091402
Kind Code:
A
Abstract:
To provide a manufacturing method and the like suppressing reduction in cylindricity of a cylinder even when employing forging.SOLUTION: A manufacturing method as a method for manufacturing a bottomed cylindrical cylinder 10 used for a dash pot 100a comprises: performing extrusion processing to a to-be-forged material 310 having a prescribed length by a first projection part 234a to form a first recessed part 310d1 on the forged material 310 (S50); and performing extrusion processing to the bottom surface 310d2 of the first recessed part 310d1 by a second projection part 235a to form a second recessed part 310e1 spatially continued to the first recessed part 310d1 (S60). The inner diameter D2 of the first recessed part 310d1 is larger than the inner diameter D1 of the second recessed part 310e1.SELECTED DRAWING: Figure 5
Inventors:
YOSHIMURA YO
MATSUURA YOSHINORI
BABA SEIJI
MATSUURA YOSHINORI
BABA SEIJI
Application Number:
JP2020204222A
Publication Date:
June 21, 2022
Filing Date:
December 09, 2020
Export Citation:
Assignee:
PANASONIC HOLDINGS CORP
International Classes:
B21K21/14; B21J5/06; H01H73/36; H02B1/42
Attorney, Agent or Firm:
Hiroi Arai
Teraya Eisaku
Shinichi Michizaka
Teraya Eisaku
Shinichi Michizaka