A hat-shaped cross-section component manufacturing apparatus includes: a die that includes a forming face that grips and presses a metal stock sheet; a blank holder, that includes a forming face that grips and presses the metal stock sheet so as to configure a forming face corresponding to the forming face of the die, a pad that is disposed inside the opening formed in the die, and that includes a forming face that grips and presses the metal stock sheet; and a punch that is disposed facing the pad and that includes a forming face that grips and presses the metal stock sheet so as to configure a forming face corresponding to the forming face of the pad. The hat-shaped cross-section component manufacturing apparatus further includes a pressure limiting device that limits a formed curving component from being pressed between the pad and the blank holder during demolding.

A hat-shaped cross-section component manufacturing apparatus includes: a die that includes a forming face that grips and presses a metal stock sheet; a blank holder, that includes a forming face that grips and presses the metal stock sheet so as to configure a forming face corresponding to the forming face of the die, a pad that is disposed inside the opening formed in the die, and that includes a forming face that grips and presses the metal stock sheet; and a punch that is disposed facing the pad and that includes a forming face that grips and presses the metal stock sheet so as to configure a forming face corresponding to the forming face of the pad. The hat-shaped cross-section component manufacturing apparatus further includes a pressure limiting device that limits a formed curving component from being pressed between the pad and the blank holder during demolding.

A cushion pin device for a press having a cushion pad in which a blank holder is seated on the top thereof outside a lower mold, and locks a blank holder to an upper mold while pressurizing an edge of a molded panel, includes: a cushion support disposed below the cushion pad, a cushion cylinder connected with a lower part of the cushion pad to move up or down the cushion pad from the cushion support, a linear scale mounted between the cushion pad and the cushion support to measure the position of the cushion pad, a main pressure control unit that keeps internal pressure of each cushion cylinder similarly, and a sub pressure control unit that is interconnected with the main pressure control unit so as to control the locking position of the cushion pad when each cushion cylinder operates.

A cushion pin device for a press having a cushion pad in which a blank holder is seated on the top thereof outside a lower mold, and locks a blank holder to an upper mold while pressurizing an edge of a molded panel, includes: a cushion support disposed below the cushion pad, a cushion cylinder connected with a lower part of the cushion pad to move up or down the cushion pad from the cushion support, a linear scale mounted between the cushion pad and the cushion support to measure the position of the cushion pad, a main pressure control unit that keeps internal pressure of each cushion cylinder similarly, and a sub pressure control unit that is interconnected with the main pressure control unit so as to control the locking position of the cushion pad when each cushion cylinder operates.

The present disclosure is applied to a press molding method for press-molding a workpiece by a press die composed of an upper die and a lower die while holding the workpiece by a die cushion. The press molding method according to the present disclosure includes pressing process, in which a press position at which the workpiece is pressed by the press die is gradually lowered while repeatedly pressing and releasing the workpiece by the press die a plurality of times until the press position reaches a bottom dead center, wherein in the pressing process, a holding force for holding the workpiece by the die cushion is controlled separately from a press molding force for press-molding the workpiece by the press die.

The present disclosure is applied to a press molding method for press-molding a workpiece by a press die composed of an upper die and a lower die while holding the workpiece by a die cushion. The press molding method according to the present disclosure includes pressing process, in which a press position at which the workpiece is pressed by the press die is gradually lowered while repeatedly pressing and releasing the workpiece by the press die a plurality of times until the press position reaches a bottom dead center, wherein in the pressing process, a holding force for holding the workpiece by the die cushion is controlled separately from a press molding force for press-molding the workpiece by the press die.

In a press machine having a die cushion device which supports a cushion pad and which generates a die cushion force when a slide of the press machine is lowered, the wrinkle generation detection device includes: a slide position detector which detects a height position of the slide; a cushion pad position detector which detects a height position of the cushion pad; and a computing unit which consecutively calculates a deviation between the height position of the slide detected by the slide position detector and the height position of the cushion pad detected by the cushion pad position detector, during a time period from the start of forming of a material by the slide lowering to the end of the forming, wherein a wrinkle generated in the material is detected based on an increase of the deviation consecutively calculated by the computing unit.

In a press machine having a die cushion device which supports a cushion pad and which generates a die cushion force when a slide of the press machine is lowered, the wrinkle generation detection device includes: a slide position detector which detects a height position of the slide; a cushion pad position detector which detects a height position of the cushion pad; and a computing unit which consecutively calculates a deviation between the height position of the slide detected by the slide position detector and the height position of the cushion pad detected by the cushion pad position detector, during a time period from the start of forming of a material by the slide lowering to the end of the forming, wherein a wrinkle generated in the material is detected based on an increase of the deviation consecutively calculated by the computing unit.

A curved part 10 having a hat-shaped cross section is produced by press-forming without causing cracks and wrinkles. When producing a curved part 10, which is made up of a top plate 11, vertical walls 12a and 12b extended in parallel with each other along ridgelines 14a and 14b of the top plate, and outwardly directed flanges 13a and 13b which connect to leading edges of the vertical walls, and has a generally hat-shaped cross section, by press forming, the metal material sheet 601 is interposed and constrained by the die 502 and the blank holder 505 and is press-formed while the metal material sheet 601 being interposed and constrained by the pad 503 and the punch 504.

A curved part 10 having a hat-shaped cross section is produced by press-forming without causing cracks and wrinkles. When producing a curved part 10, which is made up of a top plate 11, vertical walls 12a and 12b extended in parallel with each other along ridgelines 14a and 14b of the top plate, and outwardly directed flanges 13a and 13b which connect to leading edges of the vertical walls, and has a generally hat-shaped cross section, by press forming, the metal material sheet 601 is interposed and constrained by the die 502 and the blank holder 505 and is press-formed while the metal material sheet 601 being interposed and constrained by the pad 503 and the punch 504.