Stator for AC motor
A stator of an alternating current (AC) motor is disclosed. The stator includes a stator core having a divided structure including and an outer stator core fitted around the inner stator core while being connected to an inner circumference of the inner stator core. The inner stator core has a rotor insertion hole formed at the inner circumference of the inner stator core and a plurality of tooth members arranged in a circumferential direction at an outer circumference of the inner stator core. Since the coils are wound directly on the tooth members through intervals between the neighboring tooth members at the outer circumference of the inner stator core, manufacturing of the stator is facilitated. In addition, since insertion of the coils into the slots is not performed through gaps formed on an inner side of the inner stator core where the rotor insertion hole is formed, the gaps may be minimized. As a result, the performance of the AC motor is improved.
1. A stator for an alternating current (AC) motor, comprising:
a stator core having a divided structure comprising an inner stator core and an outer stator core fitted around the inner stator core while being connected to an inner circumference of the inner stator core, the inner stator core having a rotor insertion hole formed at the inner circumference of the inner stator core and a plurality of tooth members arranged in a circumferential direction at an outer circumference of the inner stator core to wind coils thereon;
wherein the inner stator core comprises a plurality of layer units stacked in a lengthwise direction while being coupled together;
wherein the plurality of layer units comprise ring-shaped integrated layer units each having a plurality of integrally-connected teeth, and separate layer units each having a plurality of separate teeth, the integrally-connected teeth of the integrated layer units and the separate teeth of the separate layer units forming the plurality of tooth members; and
wherein the integrated layer units are disposed at opposite longitudinal ends of the inner stator core, and the separate layer units are disposed between the integrated layer units.
2. The AC motor stator according to claim 1 , further comprising a gap defined between circumferentially-neighboring ones of the tooth members, wherein the gap is twice an air gap defined between a rotor and the rotor insertion hole.
3. The AC motor stator according to claim 1 , wherein one or two of the integrated layer units are disposed at each longitudinal end of the inner stator core.
4. The AC motor stator according to claim 1 , further comprising an insulator connected to the inner stator core so as to insulate the coils from the stator core,
wherein the insulator includes guards to support exposed parts of the coils to the outer stator core, and
wherein the guards are formed at positions of the insulator corresponding to the inner and outer circumferences of the inner stator core, to extend in a lengthwise direction of the inner stator core.