Motor having wiring arrangement with respect to stator insulation and circuit
In an inner-rotor motor, an armature includes a stator core including an annular core back and magnetic pole teeth projecting from the core back; an insulator covering an upper and lower surface of each magnetic pole tooth of the stator core; and coils defined by a conducting wire wound around a separate one of the magnetic pole teeth with the insulator intervening therebetween. The insulator includes at least one protruding portion. An upper end of each protruding portion is arranged at an axial level higher than an axial level of a lower surface of a circuit board. The circuit board includes at least one penetration portion each of which is defined by a cut or a hole, and in each of which a corresponding one of the at least one protruding portion is arranged.
1. A motor comprising:
a shaft extending along a central axis extending in a vertical direction, and rotatably supported by a bearing portion;
a rotor magnet configured to rotate together with the shaft;
an armature arranged radially outside the rotor magnet; and
a circuit board held on an axially upper side of the armature, and configured to supply electricity to the armature; wherein
the armature includes:
a stator core including an annular core back and a plurality of magnetic pole teeth arranged to project radially inward from the core back;
an insulator arranged to cover at least an upper surface and a lower surface of each of the plurality of magnetic pole teeth of the stator core; and
coils each of which is defined by a conducting wire wound around a separate one of the plurality of magnetic pole teeth with the insulator intervening therebetween;
the insulator includes at least one protruding portion;
an upper end of each protruding portion is arranged at an axial level higher than an axial level of a lower surface of the circuit board;
the circuit board includes at least one penetration portion each of which is defined by a cut or a hole, and in each of which a corresponding one of the at least one protruding portion is arranged;
the conducting wire is drawn out from the armature axially upwardly of the circuit board through at least one of the at least one penetration portion, and is soldered to a land portion on an upper surface of the circuit board; and
the insulator includes a window portion defined by axially downward cut with a lower end arranged at an axial level lower than an axial level of the lower surface of the circuit board, the window portion being arranged radially opposite a corresponding one of the at least one penetration portion.
2. The motor according to claim 1 , wherein the at least one protruding portion includes at least one hook portion, each of which extends axially upwardly of the upper surface of the circuit board, each hook portion including a hook-shaped portion arranged to be in contact with or opposite to the upper surface of the circuit board.
3. The motor according to claim 2 , wherein
each of the at least one hook portion is arranged circumferentially between adjacent ones of the plurality of magnetic pole teeth, and the hook-shaped portion of each hook portion is arranged to project radially inward; and
no portion of the insulator exists at a position where the hook-shaped portion of each hook portion projects radially inward.
4. The motor according to claim 2 , wherein one of the at least one penetration portion which corresponds to each of the at least one hook portion includes a portion arranged to extend in a circumferential direction from the hook portion, and the conducting wire is drawn out through this portion.
5. The motor according to claim 2 , wherein
the at least one protruding portion includes a protruding positioning portion arranged to make circumferential or radial contact with a corresponding one of the at least one penetration portion, the corresponding penetration portion including a radially inner portion extending radially inward from the protruding positioning portion;
the at least one hook portion is at least two in number;
the at least one penetration portion is at least three in number;
one of the penetration portions is arranged to be in contact with one circumferential side surface of one of the hook portions; and
another one of the penetration portions is arranged to be in contact with an opposite circumferential side surface of another one of the hook portions.
6. The motor according to claim 1 , wherein at least one of the at least one protruding portion is shaped to have a contour extending along a contour of a corresponding one of the at least one penetration portion in a plan view.
7. The motor according to claim 1 , wherein the at least one protruding portion includes a protruding positioning portion arranged to make circumferential or radial contact with a corresponding one of the at least one penetration portion.
8. The motor according to claim 7 , wherein the corresponding one of the at least one penetration portion includes a radially inner portion extending radially inward from the protruding positioning portion, and the conducting wire is drawn out through the radially inner portion of the penetration portion.
9. The motor according to claim 1 , wherein
the at least one penetration portion is more than one in number;
at least one of the at least one penetration portion is arranged to be in contact with one circumferential side surface of a corresponding one of the at least one protruding portion; and
at least one of the at least one penetration portion is arranged to be in contact with an opposite circumferential side surface of a corresponding one of the at least one protruding portion.
10. The motor according to claim 1 , wherein the at least one penetration portion is four in number, and is arranged at four different circumferential positions.
11. The motor according to claim 1 , further comprising an upper bracket arranged axially above the circuit board to cover the circuit board, wherein a portion of the upper surface of the circuit board is arranged to be in contact with a lower surface of the upper bracket.
12. The motor according to claim 11 , wherein
the upper bracket is in a shape of a covered cylinder, including a cylindrical portion and a cover portion arranged to close an axially upper end thereof; and
a lower surface of the cover portion of the upper bracket is arranged to be in contact with the circuit board.
13. The motor according to claim 12 , wherein the upper bracket includes a holding portion configured to hold the bearing portion at a center of the cover portion.
14. The motor according to claim 1 , wherein a number of poles of the armature is six.
15. The motor according to claim 1 , further comprising:
an upper bracket arranged axially above the circuit board to cover the circuit board; and
a fixing member; wherein
the circuit board further includes a fixing member insertion portion defined by a cut or a hole; and
the fixing member is fixed to the armature through the fixing member insertion portion to fix the upper bracket to the armature.
16. The motor according to claim 1 , wherein
the insulator includes passage line guide walls each of which is arranged circumferentially between adjacent ones of the magnetic pole teeth to guide at least one passage line connecting the coils with one another; and
each passage line guide wall is arranged on an axially lower side of the insulator.
17. The motor according to claim 1 , wherein the circuit board includes a control IC mounted thereon.
18. The motor according to claim 1 , wherein
the motor is a DC brushless motor; and
the circuit board has an AC-DC converter mounted thereon.