Formed material manufacturing method

Patent metadata

Field	Value
Publication number	US-2016144418-A1
Application number	US-201414782848-A
Country	US
Kind code	A1
Filing date	Nov 7, 2014
Priority date	May 19, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

A formed material having a tubular body and a flange formed at an end of the body is manufactured by multistage drawing of a blank metal sheet. The multistage drawing includes preliminary drawing in which a preliminary body having a body preform is formed from the blank metal sheet, and at least one compression drawing which is performed after the preliminary drawing and in which the body is formed by drawing the body preform while applying a compressive force to the body preform. The at least one compression drawing is performed so as to be completed before the pad portion of pressurization means reaches bottom dead center, and a support force supporting the pad portion acts as the compressive force upon the body preform when the body preform is drawn.

First claim

1 . A formed material manufacturing method of manufacturing a formed material having a tubular body and a flange, which is formed at an end portion of the body, by performing multistage drawing of a blank metal sheet, wherein
the multistage drawing includes: preliminary drawing in which a preliminary body having a body preform is formed from the blank metal sheet; and at least one compression drawing which is performed after the preliminary drawing by using a mold including a die having a press-in hole, a punch inserted into the body preform to press the body preform into the press-in hole, and pressurization means for applying a compressive force along a depth direction of the body preform to a circumferential wall of the body preform, and in which the body is formed by drawing the body preform while applying the compressive force to the circumferential wall of the body preform; the pressurization means is a lifter pad having a pad portion which is disposed at the outer circumferential position of the punch so as to face the die and onto which a lower end of the circumferential wall of the body preform is placed, and a support portion which supports the pad portion from below and which is configured such that a support force that supports the pad portion can be adjusted; at least one compression drawing is performed to be completed before the pad portion reaches bottom dead center; and the support force acts as the compression force upon the circumferential wall of the body preform when the drawing of the body preform is performed.

2 . The formed material manufacturing method according to claim 1 , wherein where a value (N/mm 2 ) obtained by dividing the compressive force applied to the circumferential wall of the body preform by a cross-sectional area of a circumferential wall of the body preform is denoted by P and a ratio of the die shoulder radius (mm) to the thickness (mm) of the circumferential wall of the body preform before the compressive force is applied and the drawing is performed is denoted by x,
163x −1.2 ≦P≦130x 0.3 is satisfied.

3 . The formed material manufacturing method according to claim 1 , wherein
the body includes a top wall and a circumferential wall protruding from an outer edge of the top wall; and the thickness of the circumferential wall of the body is equal to or greater than at least one of a maximum thickness of the top wall of the body and the thickness of the blank metal sheet.

Assignees

• Nisshin Steel Co Ltd

Inventors

• Nakamura Naofumi
• Yamamoto Yudai
• Nishio Katsuhide

Classifications

• B21D24/00 Primary

  Special deep-drawing arrangements in, or in connection with, presses · CPC title

• B21D22/28

  of cylindrical articles using consecutive dies · CPC title

• B21D22/26

  for making peculiarly, e.g. irregularly, shaped articles · CPC title

• B21D22/30

  to finish articles formed by deep-drawing · CPC title