Punching sheet used for manufacturing rotor and permanent magnet motor comprising rotor

A punching sheet used for manufacturing a rotor, comprising an axle hole, an outer edge, and a plurality of mounting grooves for receiving permanent magnets;

• wherein
• the axle hole is disposed at a center of the punching sheet, and the plurality of mounting grooves are disposed in the proximity of the outer edge of the punching sheet;
• the outer edge of the punching sheet comprises a plurality of arcs;
• the plurality of the arcs are connected to one another;
• the plurality of arcs are of equal arc length and equal radius;
• the plurality of arcs have a radius of R2;
• a center of each of the plurality of arcs deviates from a center of the axle hole;
• and
• a circle centered at the center of the axle hole and tangent to the plurality of arcs has a radius of R1, and 0.7R1≤R2≤0.9R1.