Magnetic core for an electric motor

A method for making a magnetic core for an electric motor, comprising the following steps:

• step S1:
• forming a plurality of elongated sheet materials by punching, with each sheet material including a connecting portion and a plurality of teeth extending from the connecting portion, each tooth including a tooth tip extending from a distal end of the tooth to two sides thereof, the tooth tip including a left half tooth tip and a right half tooth tip;
• each sheet material including a plurality of groups of teeth each having a first type tooth, a second type tooth, a third type tooth and a fourth type tooth that are sequentially arranged, the left half tooth tip of the first type tooth being a short tooth tip, the right half tooth tip of the first type tooth being a long tooth tip, the left and right half tooth tips of the second type tooth are both short tooth tips, the left half tooth tip of the third type tooth being a long tooth tip, the right half tooth tip of the third type tooth being a short tooth tip, the left and right half tooth tips of the fourth type tooth being both long tooth tips;
• step S2:
• stacking multiple sheet materials to form multiple layers of core laminations, with the first type tooth of at least one lamination layer overlapping with the third type tooth of another lamination layer, the second type tooth of the at least one lamination layer overlapping with the fourth type tooth of the another lamination layer, the third type tooth of the at least one lamination layer overlapping with the first type tooth of the another lamination layer, and the fourth type tooth of the at least one lamination layer overlapping with the second type tooth of the another lamination layer;
• and
• step S3:
• bending the stacked multiple layers of core laminations into a ring shape, with the connecting portions of all sheet materials making a ring-shaped yoke, and the teeth of each sheet material extending outwardly from the yoke.

A method for making a magnetic core for an electric motor, comprising the following steps:

• step S1:
• forming an elongated sheet material by punching, with the sheet material including a connecting portion and a plurality of teeth extending from the connecting portion, each tooth including a tooth tip extending from a distal end of the tooth to two sides thereof, the tooth tip including a left half tooth tip and a right half tooth tip;
• the sheet material including a plurality of groups of teeth each having a first type tooth, a second type tooth, a third type tooth and a fourth type tooth that are sequentially arranged, the left half tooth tip of the first type tooth being a short tooth tip, the right half tooth tip of the first type tooth being a long tooth tip, the left and right half tooth tips of the second type tooth are both short tooth tips, the left half tooth tip of the third type tooth being a long tooth tip, the right half tooth tip of the third type tooth being a short tooth tip, the left and right half tooth tips of the fourth type tooth being both long tooth tips;
• and
• step S2:
• spirally rolling the sheet material multiple turns, with each turn forming a lamination layer of the magnetic core, each lamination layer including a ring-shaped yoke and the teeth extending from the yoke;
• with the first type tooth of at least one lamination layer overlapping with the third type tooth of another lamination layer, the second type tooth of the at least one lamination layer overlapping with the fourth type tooth of the another lamination layer, the third type tooth of the at least one lamination layer overlapping with the first type tooth of the another lamination layer, and the fourth type tooth of the at least one lamination layer overlapping with the second type tooth of the another lamination layer.