Electric motor with commutator segments, anode and cathode brushes and coils having varying number of turns based on anode brush position angle

Patent metadata

Field	Value
Publication number	US-10367401-B2
Application number	US-201515112537-A
Country	US
Kind code	B2
Filing date	Mar 5, 2015
Priority date	Mar 14, 2014
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

In a 4-pole, 6-slot, 18-segment electric motor, one forward winding coil ( 91 ) and two reverse winding coils ( 92, 93 ) are wound on each tooth ( 12 ). When the forward winding coils are formed of coils corresponding to a U phase, a V phase, and a W phase and the reverse winding coils are formed of coils corresponding to a “−U” phase, a “−V” phase, and a “−W” phase, the coils, which correspond to a U phase, a “−W” phase, a “−W” phase, a V phase, a “−U” phase, a “−U” phase, a W phase, a “−V” phase, and a “−V” phase, are electrically connected in this order between the adjacent segments. When the number of turns of the coils ( 91 ) corresponding to a U phase, a V phase, and a W phase is denoted by T1, the number of turns of the coils ( 92 ), which correspond to a “−U” phase, a “−V” phase, and a “−W” phase and first come into sliding contact with a brush, is denoted by T2, and the number of turns of the coils ( 93 ), which correspond to a “−U” phase, a “−V” phase, and a “−W” phase and later come into sliding contact with the brush, is denoted by T3, “T2>T1>T3” is satisfied.

First claim

The invention claimed is:

1. An electric motor comprising:
a motor magnet in which a plurality of magnetic poles are arranged in a circumferential direction;
a rotating shaft that is rotatably provided inside the motor magnet;
an armature core that is mounted on the rotating shaft and includes a plurality of teeth radially extending outward in a radial direction and a plurality of slots formed between the teeth;
coils that are wound on each of the teeth in a concentrated winding manner;
a commutator which is provided so as to rotate integrally with the rotating shaft and on which a plurality of segments are disposed in the circumferential direction; and
an anode brush and a cathode brush that supply power to the coils through the segments,
wherein three coils are wound on each of the teeth,
a number of turns of one coil among the three coils is set to be smaller than a number of turns of each of the other two coils,
the three coils are an advance-angle coil of which a magnetomotive force vector is directed to an advance-angle side, a delay-angle coil of which a magnetomotive force vector is directed to a delay-angle side, and a normal coil of which a magnetomotive force vector is not directed to either the advance-angle side or the delay-angle side, and
when the number of turns of the advance-angle coil is denoted by T 1 , the number of turns of the normal coil is denoted by T 2 , and the number of turns of the delay-angle coil is denoted by T 3 ,
in a case in which,
an advance angle θ 1 of the magnetomotive force vector of the advance-angle coil satisfies 0°<θ 1 ≤20°,
a delay angle θ 2 of the magnetomotive force vector of the delay-angle coil satisfies 0°<θ 2 ≤20°, and
an advance angle θ 3 of a position of the anode brush satisfies 0°≤θ 3 ≤3°,

T 1 , T 2 , and T 3 are set so as to satisfy T 2 >T 1 >T 3 .

2. The electric motor according to claim 1 ,
wherein the number of the magnetic poles is set to four, the number of the slots is set to six, and the number of the segments is set to eighteen,
the three coils wound on each tooth are formed of one forward winding coil that is wound in a forward direction and two reverse winding coils wound in a reverse direction,
when a U phase, a V phase, and a W phase are assigned to each tooth in this order in the circumferential direction, the forward winding coils wound to the respective phases are respectively referred to as a U phase, a V phase, and a W phase, and the reverse winding coils wound to the respective phases are respectively referred to as a −U phase, a −V phase, and a −W phase, the coils of the U phase, the −W phase, the −W phase, the V phase, the −U phase, the −U phase, the W phase, the −V phase, and the −V phase are electrically connected in this order between the adjacent segments, and
the number of turns of one coil among the one forward winding coil and the two reverse winding coils, which are wound, is set to be smaller than the number of turns of each of the other two coils.

3. An electric motor comprising:
a motor magnet in which a plurality of magnetic poles are arranged in a circumferential direction;
a rotating shaft that is rotatably provided inside the motor magnet;
an armature core that is mounted on the rotating shaft and includes a plurality of teeth radially extending outward in a radial direction and a plurality of slots formed between the teeth;
coils that are wound on each of the teeth in a concentrated winding manner;
a commutator which is provided so as to rotate integrally with the rotating shaft and on which a plurality of segments are disposed in the circumferential direction; and
an anode brush and a cathode brush that supply power to the coils through the segments,
wherein three coils are wound on each of the teeth,
a number of turns of one coil among the three coils is set to be smaller than a number of turns of each of the other two coils,
the three coils are an advance-angle coil of which a magnetomotive force vector is directed to an advance-angle side, a delay-angle coil of which a magnetomotive force vector is directed to a delay-angle side, and a normal coil of which a magnetomotive force vector is not directed to either the advance-angle side or the delay-angle side, and
when the number of turns of the advance-angle coil is denoted by T 1 , the number of turns of the normal coil is denoted by T 2 , and the number of turns of the delay-angle coil is denoted by T 3 ,
in a case in which
an advance angle θ 1 of the magnetomotive force vector of the advance-angle coil satisfies 0°<θ 1 ≤20°,
a delay angle θ 2 of the magnetomotive force vector of the delay-angle coil satisfies 0°<θ 2 ≤20° and
an advance angle θ 3 of a position of the anode brush satisfies 3°<θ 3 ≤10°,

T 1 , T 2 , and T 3 are set so as to satisfy T 2 >T 3 >T 1 .

4. The electric motor according to claim 3 ,
wherein the number of the magnetic poles is set to four, the number of the slots is set to six, and the number of the segments is set to eighteen,
the three coils wound on each tooth are formed of one forward winding coil that is wound in a forward direction and two reverse winding coils wound in a reverse direction,
when a U phase, a V phase, and a W phase are assigned to each tooth in this order in the circumferential direction, the forward winding coils wound to the respective phases are respectively referred to as a U phase, a V phase, and a W phase, and the reverse winding coils wound to the respective phases are respectively referred to as a −U phase, a −V phase, and a −W phase, the coils of the U phase, the −W phase, the −W phase, the V phase, the −U phase, the −U phase, the W phase, the −V phase, and the −V phase are electrically connected in this order between the adjacent segments, and
the number of turns of one coil among the one forward winding coil and the two reverse winding coils, which are wound, is set to be smaller than the number of turns of each of the other two coils.

5. An electric motor comprising:
a motor magnet in which a plurality of magnetic poles are arranged in a circumferential direction;
a rotating shaft that is rotatably provided inside the motor magnet;
an armature core that is mounted on the rotating shaft and includes a plurality of teeth radially extending outward in a radial direction and a plurality of slots formed between the teeth;
coils that are wound on each of the teeth in a concentrated winding manner;
a commutator which is provided so as to rotate integrally with the rotating shaft and on which a plurality of segments are disposed in the circumferential direction; and
an anode brush and a cathode brush that supply power to the coils through the segments,
wherein three coils are wound on each of the teeth,
a number of turns of one coil among the three coils is set to be smaller than a number of turns of each of the other two coils,
the three coils are an advance-angle coil of which a magnetomotive force vector is directed to an advance-angle side, a delay-angle coil of which a magnetomotive force vector is directed to a delay-angle side, and a normal coil of which a magnetomotive force vector is not directed to either the advance-angle side or the delay-angle side, and
when the number of turns of the advance-angle coil is denoted by T 1 , the number of turns of the normal coil is denoted by T 2 , and the number of turns of the delay-angle coil is denoted by T 3
in a case in which
an advance angle θ 1 of the magnetomotive force vector of the advance-angle coil satisfies 0°<θ 1 ≤20°,
a delay angle θ 2 of the magnetomotive force vector of the delay-angle coil satisfies 0°<θ 2 ≤20°, and
an advance angle θ 3 of a position of the anode brush satisfies θ 3 =20°,

T 1 , T 2 , and T 3 are set so as to satisfy T 3 >T 2 >T 1 .

6. T

Assignees

• Mitsuba Corp

Inventors

• Tamura Natsumi
• Tanaka Hiroto
• Tokizaki Teppei
• Tamura Satoshi

Classifications

• H02K1/17

  Stator cores with permanent magnets · CPC title

• H02K7/1166

  comprising worm and worm-wheel (structural association with bearings specially adapted for worm gear drives H02K7/081) · CPC title

• H02K23/38 Primary

  having winding or connection for improving commutation, e.g. equipotential connection · CPC title

• H02K1/24

  Rotor cores with salient poles {; Variable reluctance rotors} · CPC title

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title