Abstract: When provisionally blanking a lamination sheet by using a punch for provisional blanking and a counter punch, the displacement of pilot holes located around the lamination sheet is minimized. The progressive die machine (1) comprises a pilot hole punch (72), a punch (9) for provisionally punching an iron core laminate (2) from a strip (W) formed with pilot holes (P), a counter punch (31) provided in a lower die assembly (5) and configured to push the iron core laminate (2) against the punch (9), a stripper plate (13) for separating the strip (W) from the provisional blanking punch after a provisional punching, a punch (10) for completely separating the iron core laminate from the strip. At least a part of the stripper plate (13) associated with the provisionally blanking is not in contact with the strip, and at least a part of an outer peripheral part of the provisionally blanked lamination sheet is formed with a connecting portion (79) connected to the strip.

Abstract: When provisionally blanking a lamination sheet by using a punch for provisional blanking and a counter punch, the displacement of pilot holes located around the lamination sheet is minimized. The progressive die machine (1) comprises a pilot hole punch (72), a punch (9) for provisionally punching an iron core laminate (2) from a strip (W) formed with pilot holes (P), a counter punch (31) provided in a lower die assembly (5) and configured to push the iron core laminate (2) against the punch (9), a stripper plate (13) for separating the strip (W) from the provisional blanking punch after a provisional punching, a punch (10) for completely separating the iron core laminate from the strip. At least a part of the stripper plate (13) associated with the provisionally blanking is not in contact with the strip, and at least a part of an outer peripheral part of the provisionally blanked lamination sheet is formed with a connecting portion (79) connected to the strip.

Abstract: In a method of manufacturing a laminated magnetic core by laser welding successive core sheets, the core sheets are stacked one on another to form a stacked body of core sheets, and while the stacked body of core sheets is moved in a stepwise manner in a thickness direction perpendicular to a surface of the core sheet with respect to at least one optical fiber exit unit from which a laser beam is projected onto an outer surface of the stacked body of core sheets, the laser beam is intermittently projected onto the stacked body of core sheets such that at least successive three core sheets are welded together, and then the stacked body of core sheets is moved in the thickness direction over a distance substantially equal to at least a twice of the thickness of core sheets.

Abstract: A die for manufacturing a laminated core for a rotor or a stator for an electric motor or a generator including rotary stacking and a skewing using a rotary die to stack the thin iron plates punched to a predetermined shape. Rotation of the crank shaft of the press is converted into a rotary stacking angle to take it out from the indexing device. Rotation of the crank shaft of the press is converted into a predetermined corresponding skew angle from the indexing device through a crank mechanism to take it out of the gear device. An amount of rotation having outputs from the indexing device and from the gear device combined with each other is taken out at the output shaft through a rotary friction transmitting mechanism and a rotation of this output shaft is applied to the rotary die.