Multi-layer blanking process and device for the manufacture of metal parts such as rotor and stator lamination sheets for an electric motor

A process for the blanking of metal parts (1;

• 10, 20) provided with one or more holes (21, 22) and/or one or more slots (11) from a layered basic material (51), wherein the metal parts (1;
• 10, 20) are blanked from the layered basic material (51) with the aid of a blanking station (102), which blanking station (102) is provided with a blank holder (70) and with a blanking die (80), each of which defines a cavity (71;
• 81) with a contour shape corresponding to that of the metals parts (1;
• 10, 20) to be blanked and with a blanking punch (32) and a counter punch (40) contained therein, whereof the blank holder (70) and the blanking die (80), on the one hand, and the blanking punch (32) and the counter punch (40), on the other hand, are movable with respect to each other, to which end the layered basic material (51) is first clamped between the blank holder (70) and the blanking die (80) on the one hand and the blanking punch (32) and the counter punch (40) on the other hand and, thereafter, the blanking punch (32) is moved through the successive layers (50) of the layered basic material (51), while supported by the counter punch (40), and thereby cuts loose a single metal part (1;
• 10, 20) from the surrounding basic material (51) per such layer (50), characterized in that, prior to such cutting loose of the metal parts (1;
• 10, 20), one or more holes (3;
• 12, 21, 22) are punched into the layered base material (51) with the aid of a further blanking station (101), which further blanking station (101) is likewise provided with a blank holder (70) and with a blanking die (80), each of which defines an opening with a contour shape corresponding to that of the holes (3;
• 12, 21, 22) to be punched and with a further blanking punch (31) contained therein, whereof the blank holder (70) and the blanking die (80) are movable with respect to the further blanking punch (31), to which end the layered base material (51) is first clamped between the blank holder (70) and the blanking die (80) and, thereafter, the further blanking punch (31) is moved through the successive layers (50) of the layered basic material (51) and thereby cuts loose a piece of scrap material (2) from the surrounding basic material (51) per such layer (50) without utilizing a counter punch.