The present disclosure relates to an electromagnetic stamping method and an electromagnetic stamping device. The electromagnetic stamping method includes: dividing a blank holder of a stamping device into a plurality of blank holder areas based on a contour characteristic of a workpiece to be stamped; setting a blank holder force function over time for each blank holder area based on a shape characteristic of the blank holder area; collecting blank holder force data of each blank holder area every cycle period t0, and calculating an error between the blank holder force data and a value of the blank holder force function at a current time; and controlling a blank holder force for each blank holder area based on the error, and obtaining the workpiece to be stamped by stamping sheet material under the blank holder force.

A forming die includes a first die component with a male bead and a second die component with a female bead. The male bead and the female bead form a bead with a reverse bead geometry with the male bead having a groove and the female bead having a protrusion complimentary with the groove such that the protrusion is aligned with the groove when the male bead extends into the female bead. Also, the protrusion is adjustable in real-time within the female bead. A stamping machine with the first die component and the second die component has a control unit configured to adjust the protrusion in real-time as a function of mechanical property testing data, width testing data, thickness testing data, lubrication testing data and/or image sensor module data on one or more blanks to be stamped and/or one or more blanks that have been stamped.

A press forming method for an automotive outer panel according to the present invention is a method for press forming a metal sheet 51 into an automotive outer panel 61 having a character line 63 and panel surface portions 65a and 65b by using a punch 3, a die 5, and a blank holder 7. The press forming method includes: a step of providing an elastic body 9 protruding toward the punch 3 side on a die-side forming surface portion 5b forming the panel surface portion 65a, and bringing the elastic body 9 into contact with the metal sheet 51 prior to the die 5; and a step of press forming while crushing the elastic body 9 and pressing the metal sheet 51, and the elastic body 9 is caused to protrude from the die-side forming surface portion 5b so that a frictional force of the crushed elastic body 9 and the metal sheet 51 is equal to or greater than an absolute value of a difference between tensions acting on. both sides of a portion 53 corresponding to the character line 63.

A press forming method for an automotive outer panel according to the present invention is a method for press forming a metal sheet 51 into an automotive outer panel 61 having a character line 63 and panel surface portions 65a and 65b by using a punch 3, a die 5, and a blank holder 7. The press forming method includes: a step of providing an elastic body 9 protruding toward the punch 3 side on a die-side forming surface portion 5b forming the panel surface portion 65a, and bringing the elastic body 9 into contact with the metal sheet 51 prior to the die 5; and a step of press forming while crushing the elastic body 9 and pressing the metal sheet 51, and the elastic body 9 is caused to protrude from the die-side forming surface portion 5b so that a frictional force of the crushed elastic body 9 and the metal sheet 51 is equal to or greater than an absolute value of a difference between tensions acting on. both sides of a portion 53 corresponding to the character line 63.

A method for manufacturing a pressed component including an elongated top plate, a wall having one end connected to a short direction end portion of the top plate, that curves with a convex shape bowing toward an opposite side to the top plate as viewed from an upper side of the top plate, and that includes a sharp curve portion, and a flange that is connected to another end of the wall, and that extends in a plate thickness direction of the wall toward the opposite side to the top plate side. The manufacturing method includes pressing to form an intermediate formed component including a preliminary flange and pressing to deform the preliminary flange to form the preliminary flange into the flange.

A method for manufacturing a pressed component including an elongated top plate, a wall having one end connected to a short direction end portion of the top plate, that curves with a convex shape bowing toward an opposite side to the top plate as viewed from an upper side of the top plate, and that includes a sharp curve portion, and a flange that is connected to another end of the wall, and that extends in a plate thickness direction of the wall toward the opposite side to the top plate side. The manufacturing method includes pressing to form an intermediate formed component including a preliminary flange and pressing to deform the preliminary flange to form the preliminary flange into the flange.

An upper die of a forming apparatus includes a first curved portion and a second curved portion between a second concave section and an upper holding surface. The first curved portion is curved in a direction away from the upper die. The second curved portion is curved toward the upper die. A blank holding surface of a blank holder holds a blank between the blank holding surface and the upper holding surface of the upper die. The blank holding surface faces the second curved portion. The blank holding surface includes a blank curved surface recessed along the second curved portion.

An upper die of a forming apparatus includes a first curved portion and a second curved portion between a second concave section and an upper holding surface. The first curved portion is curved in a direction away from the upper die. The second curved portion is curved toward the upper die. A blank holding surface of a blank holder holds a blank between the blank holding surface and the upper holding surface of the upper die. The blank holding surface faces the second curved portion. The blank holding surface includes a blank curved surface recessed along the second curved portion.

A manufacturing apparatus for a hat-shaped cross-section component includes a die having first molding surfaces, a pad having a second molding surface, a punch having a third molding surface, a holder having fourth molding surfaces, and a first restraint portion. An upright wall is molded between a top and each of flanges by moving the pad and the punch relative to the die and the holder, or moving the die and the holder relative to the pad and the punch. The first restraint portion is configured to, during a period from when a top forming part is sandwiched by the second molding surface and the third molding surface to when the upright walls are molded, suppress displacement of the top forming part in a longitudinal direction of the top forming part relative to the second molding surface and the third molding surface.

A manufacturing apparatus for a hat-shaped cross-section component includes a die having first molding surfaces, a pad having a second molding surface, a punch having a third molding surface, a holder having fourth molding surfaces, and a first restraint portion. An upright wall is molded between a top and each of flanges by moving the pad and the punch relative to the die and the holder, or moving the die and the holder relative to the pad and the punch. The first restraint portion is configured to, during a period from when a top forming part is sandwiched by the second molding surface and the third molding surface to when the upright walls are molded, suppress displacement of the top forming part in a longitudinal direction of the top forming part relative to the second molding surface and the third molding surface.