Apparatus, systems, and methods for increasing airflow through induction motors
View Patent ↗Induction motors may have a rotor core assembly that includes a plurality of rotor laminations having an arrangement of vents therein. The arrangement of vents may provide increased airflow through the induction motor without adversely affecting the electromagnetic properties of the motor. The arrangement of vents includes first and second circular rows of vents, wherein each vent of the first row may be radially aligned with a respective vent of the second row, and each radially aligned pair of first and second row vents may be radially aligned with a respective conductor bar slot in the rotor lamination. The number of rotor bar slots may equal the number of first row vents and the number of second row vents. Systems and methods of facilitating ventilation in an induction motor are provided, as are other aspects.
1. A rotor core assembly of an induction motor, comprising:
a plurality of rotor laminations, each rotor lamination comprising:
a plurality of slots arranged around an outer radial periphery of a rotor lamination and passing through the rotor lamination, each slot configured to receive a rotor conductor bar there through;
a first row of vents passing axially through the rotor lamination; and
a second row of vents passing axially through the rotor lamination; wherein:
each vent of the first row of vents has a first shape and each vent of the second row of vents has a second shape different from the first shape, and
each vent of the first row is radially aligned with a respective vent of the second row, and each pair of radially aliened first and second vents is radially aligned with a respective slot of the plurality of slots along a same radial vector such that magnetic field lines passing radially through the plurality of rotor laminations around the first row of vents, the second row of vents and the plurality of slots are substantially evenly spaced apart throughout the rotor core assembly and a magnetic flux density is substantially uniform throughout the rotor core assembly.
2. The rotor core assembly of claim 1 wherein the first row of vents is arranged in a first ring and the second row of vents is arranged in a second ring.
3. The rotor core assembly of claim 1 wherein the second row of vents is positioned radially outward from the first row of vents.
4. The rotor core assembly of claim 1 wherein the plurality of slots, the first row of vents, and the second row of vents are equal in number.
5. The rotor core assembly of claim 1 further comprising:
a plurality of rotor conductor bars inserted through the plurality of slots;
a shaft upon which the plurality of rotor laminations are mounted; and
a pair of end caps, each end cap mounted to a respective securement ring at an axial end of the rotor core assembly.
6. A rotor core assembly of an induction motor, comprising:
a plurality of rotor laminations, each rotor lamination comprising:
a plurality of slots arranged around an outer radial periphery of a rotor lamination and passing through the rotor lamination, each slot configured to receive a rotor conductor bar there through;
a first row of vents passing axially through the rotor lamination; and
a second row of vents passing axially through the rotor lamination; wherein:
at least one vent of the first row of vents has a first shape and at least one vent of the second row of vents has a second shape different from the first shape, and
each vent of the first row is radially aligned with a respective vent of the second row, and each pair of radially aligned first and second vents is radially aligned with a respective slot of the plurality of slots along a same radial vector such that magnetic field lines passing radially through the plurality of rotor laminations around the first row of vents, the second row of vents and the plurality of slots are substantially evenly spaced apart throughout the rotor core assembly and a magnetic flux density is substantially uniform throughout the rotor core assembly.
7. The rotor core assembly of claim 6 wherein the first row of vents is arranged in a first ring and the second row of vents is arranged in a second ring.
8. The rotor core assembly of claim 6 wherein the second row of vents is positioned radially outward from the first row of vents.
9. The rotor core assembly of claim 6 wherein the plurality of slots, the first row of vents, and the second row of vents are equal in number.
10. The rotor core assembly of claim 6 further comprising:
a plurality of rotor conductor bars inserted through the plurality of slots;
a shaft upon which the plurality of rotor laminations are mounted; and
a pair of end caps, each end cap mounted to a respective securement ring at an axial end of the rotor core assembly.