To provide a hydroforming method capable of increasing the sheet thickness of a corner of a hydroformed product while simplifying a device and reducing a production cost, and to provide the hydroformed product.
The hydroforming method, in which a pipe member W containing a liquid is formed into a shape with a corner while making a hydraulic pressure act by pushing the pipe member W with a mobile mold 5b that presses the pipe member W radially inwardly and a pair of right and left cam molds 4 that presses the pipe member W radially inwardly in a different direction from the mobile mold 5b, includes a pre-pressing process in which the pair of right and left cam molds 4 press the pipe member W radially inwardly prior to the pressure operation of the mobile mold 5b; a hydraulic pressure maintaining process in which the hydraulic pressure P in the pipe member W is maintained at a post-contact hydraulic pressure P1 after the pair of right and left cam molds 4 and the mobile 5b come in contact with the pipe member W; and a hydraulic pressure decreasing process in which the hydraulic pressure P in the pipe member W is decreased to a pre-bottom dead center hydraulic pressure P2, that is set lower than the post-contact hydraulic pressure P1, before the cam molds 4 and the mobile mold 5b reach a bottom dead center.
FUKAHORI MITSUGI
SAITO NAOKO
BABA TOMOHIRO
KOBAYASHI NAOYUKI
HIROTEC CORP
| JPH1147842A | 1999-02-23 | |||
| JP2004181477A | 2004-07-02 | |||
| JP2000246361A | 2000-09-12 | |||
| JP2006255750A | 2006-09-28 | |||
| JP2005238254A | 2005-09-08 | |||
| JP2012040604A | 2012-03-01 |
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