Electric motor

Abstract

When teeth ( 12 ) are allocated in a circumferential direction in sequence of a U phase, a V phase and a W phase, a forward wound coil wound on each of the phases is provided as a coil of the U phase, the V phase and the W phase, and a reverse wound coil wound on each of the phases is provided as the coil of a −U phase, a −V phase and a −W phase, the coils are electrically connected between the neighboring segments in an order 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, and the wire ( 14 ) drawn between the armature core ( 8 ) and the commutator ( 10 ) is drawn around the rotation shaft in the same direction.

1 . An electric motor comprising:
 a yoke having a plurality of magnetic poles;   a rotation shaft rotatably installed inside the yoke;   an armature core having a plurality of teeth attached to the rotation shaft and radially extending in a radial direction, and a plurality of slots formed between the teeth;   a coil wound on each of the teeth through an concentrated winding method;   a commutator installed at the rotation shaft adjacent to the armature core and having a plurality of segments disposed in a circumferential direction; and   three brushes including a low speed brush and a high speed brush configured to supply power to the coil via the segments, and a common brush used in common with the low speed brush and the high speed brush,   wherein the number of magnetic poles is set to 4, the number of slots is set to 6, and the number of segments is set to 18,   the coil wound on each of the teeth comprises one forward wound coil formed to be wound forward, and two reverse wound coils formed to be wound in reverse,   when the teeth are allocated in the circumferential direction in sequence of a U phase, a V phase and a W phase, the forward wound coil wound on each of the phases is provided as the coil of the U phase, the V phase and the W phase, and the reverse wound coil wound on each of the phases is provided as the coil of a −U phase, a −V phase and a −W phase,   the coils are electrically connected between the neighboring segments in the order 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, and   the coil drawn between the armature core and the commutator is drawn around the rotation shaft in the same direction.   
     
     
         2 . An electric motor comprising:
 a yoke having a plurality of magnetic poles;   a rotation shaft rotatably installed inside the yoke;   an armature core having a plurality of teeth attached to the rotation shaft and radially extending in a radial direction, and a plurality of slots formed between the teeth;   a coil wound on each of the teeth through an concentrated winding method;   a commutator installed at the rotation shaft adjacent to the armature core and having a plurality of segments disposed in a circumferential direction; and   two brushes configured to supply power to the coil via the segments,   wherein the number of magnetic poles is set to 4, the number of slots is set to 6, and the number of segments is set to 18,   the coil wound on each of the teeth comprises one forward wound coil formed to be wound forward, and two reverse wound coils formed to be wound in reverse,   when the teeth are allocated in the circumferential direction in sequence of a U phase, a V phase and a W phase, the forward wound coil wound on each of the phases is provided as the coil of the U phase, the V phase and the W phase, and the reverse wound coil wound on each of the phases is provided as the coil of a −U phase, a −V phase and a −W phase,   the coils are electrically connected between the neighboring segments in the order 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, and   the coil drawn between the armature core and the commutator is drawn around the rotation shaft in the same direction.   
     
     
         3 . The electric motor according to  claim 1  or  2 , wherein, in the segments, the segments having the same electric potential are connected to each other by a connecting wire,
 when 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 formed, the connecting wire is formed in series along with 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, 
 when the connecting wire is formed, the coil is drawn in the same direction as when it is drawn between the armature core and the commutator, and 
 the coil is wound around a riser formed at the segment by an a turn to connect the segment and the coil. 
 
     
     
         4 . The electric motor according to  claim 1  or  2 , further comprising an insulator configured to cover at least peripheries of the teeth and having an insulation property,
 wherein the coil is formed by winding a wire on the teeth from above the insulator, 
 a partition section configured to determine a place at which at least one of a plurality of the coils are disposed is installed at the insulator, and 
 at least two accommodating portions configured to accommodate the coil are formed on the insulator by the partition section. 
 
     
     
         5 . The electric motor according to  claim 4 , wherein the partition section is installed at least at one end in an axial direction of the insulator. 
     
     
         6 . The electric motor according to  claim 4  or  5 , wherein the partition section is installed throughout the entire circumference of the insulator. 
     
     
         7 . The electric motor according to any one of  claims 4  to  6 , wherein the partition section is installed such that capacities of the accommodating portions are substantially uniformized. 
     
     
         8 . The electric motor according to any one of  claims 4  to  7 , wherein protrusion heights of the partition sections are different from each other. 
     
     
         9 . The electric motor according to  claim 8 , wherein the protrusion heights of the partition sections are set to be lower as the partition sections are disposed more inside in the radial direction. 
     
     
         10 . The electric motor according to any one of  claims 4  to  9 , wherein the plurality of the coils are accommodated in the accommodating portions in sequence from the accommodating portion disposed inside in the radial direction to the accommodating portion disposed outside in the radial direction.