FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
STATOR, MOTOR, COMPRESSOR, AIR CONDITIONER, AND MANUFACTURING METHOD
OF STATOR
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED AND
EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-3, MARUNOUCHI
2-CHOME, CHIYODA-KU, TOKYO 1008310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION
AND THE MANNER IN WHICH IT IS TO BE PERFORMED
2
DESCRIPTION
TECHNICAL FIELD
[0001]
The present invention relates to a stator, a motor, a 5 compressor, an air conditioner, and a manufacturing method of a
stator.
BACKGROUND ART
[0002]
Winding methods of coils of a stator of a motor include 10 concentrated winding and distributed winding. The distributed
winding has an advantage of easily suppressing noise and
vibration and is widely used, for example, in motors for
compressors. Patent references 1 to 7 disclose various types of
stators employing the distributed winding. 15 PRIOR ART REFERENCE
PATENT REFERENCE
[0003]
[PATENT REFERENCE 1] Japanese Patent Application Publication No.
2004-40897 20 [PATENT REFERENCE 2] Japanese Patent Application Publication No.
2004-194435
[PATENT REFERENCE 3] Japanese Patent Application Publication No.
4-156245
[PATENT REFERENCE 4] Japanese Patent Publication No. 5095276 25 [PATENT REFERENCE 5] Japanese Patent Application Publication No.
62-230346
[PATENT REFERENCE 6] Japanese Utility Model Application
Publication No. 62-178757
[PATENT REFERENCE 7] Japanese Patent Application Publication No. 30 2001-186728
SUMMARY OF THE INVENTION
PROBLEM TO BE SOLVED BY THE INVENTION
[0004]
3
However, in a conventional stator employing the distributed
winding, coil ends tend to be large, and the manufacturing cost
tends to be high. When the coil ends are reduced in size, a
winding factor decreases, and thus the motor efficiency decreases.
Therefore, it is required to improve the motor efficiency while 5 reducing the manufacturing cost.
[0005]
The present invention is intended to solve the abovedescribed
problems, and an object of the present invention is to
improve the motor efficiency while reducing the manufacturing 10 cost.
MEANS OF SOLVING THE PROBLEM
[0006]
A stator of the present invention includes a stator core
having a plurality of slots in a circumferential direction about 15 an axis and having an end surface in a direction of the axis, and
a first coil and a second coil of different phases which are
wound on the stator core in distributed winding. A winding
factor is 1. Each of the first coil and the second coil has
winding portions, the number of which corresponds to the number 20 of poles. The winding portions, the number of which corresponds
to the number of poles, include a first winding portion and a
second winding portion that are adjacent to each other in the
circumferential direction. The first winding portion and the
second winding portion are inserted into one slot of the 25 plurality of slots and extend from the one slot to both sides in
the circumferential direction on the end surface. The first coil
and the second coil are annularly disposed in different positions
in a radial direction about the axis on the end surface of the
stator core. 30 EFFECTS OF THE INVENTION
[0007]
In the present invention, the first winding portion and the
second winding portion are inserted into one slot and extend from
4
the slot to both sides in the circumferential direction on the
end surface of the stator core. Thus, the coils can be arranged
dispersedly in the circumferential direction, and a size of a
portion (coil end) protruding outward from the stator core in the
axial direction can be reduced. Therefore, a circumference 5 length of each coil can be shortened, and the winding factor can
be set to 1, so that the motor efficiency can be improved.
Further, since the first coil and the second coil are annularly
disposed in different positions in the radial direction, winding
of the coils on the stator core is facilitated, and thus the 10 manufacturing cost can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008]
FIG. 1 is a cross-sectional view illustrating a motor of a
first embodiment. 15 FIG. 2 is a cross-sectional view illustrating a stator of
the first embodiment.
FIG. 3 is a plan view illustrating a stator core of the
first embodiment.
FIG. 4 is a plan view illustrating the stator core and 20 coils of the first embodiment.
FIG. 5 is a plan view illustrating the stator core, the
coils, and insulating films of the first embodiment.
FIG. 6(A) is a perspective view illustrating a first
winding portion of a U-phase coil of the first embodiment, FIG. 25 6(B) is a perspective view illustrating a second winding portion
of the U-phase coil, and FIG. 6(C) is a perspective view
illustrating a combination of these winding portions.
FIG. 7 is a perspective view illustrating a state in which
the U-phase coil is attached to the stator core of the first 30 embodiment.
FIG. 8 is a plan view illustrating a state in which the Uphase
coil is wound on the stator core of the first embodiment.
FIG. 9(A) is a schematic diagram illustrating a connected
5
state of the U-phase coil, the V-phase coil, and the W-phase coil
of the first embodiment, and FIG. 9(B) is a schematic diagram
illustrating a connected state of the winding portions of the Uphase
coil.
FIG. 10 is a flowchart illustrating a manufacturing process 5 of the stator of the first embodiment.
FIGS. 11(A) to 11(F) are schematic diagrams illustrating a
winding process of the U-phase coil, the V-phase coil, and the Wphase
coil of the first embodiment.
FIG. 12 is a flowchart illustrating another example of the 10 manufacturing process of the stator of the first embodiment.
FIG. 13 is a cross-sectional view illustrating a motor of
Comparative Example 1.
FIG. 14 is a cross-sectional view illustrating a motor of
Comparative Example 2. 15 FIG. 15 is a schematic diagram illustrating a stator of a
motor of Comparative Example 3.
FIG. 16(A) is a perspective view illustrating a first
winding portion of a U-phase coil of a second embodiment, FIG.
16(B) is a perspective view illustrating a second winding portion 20 of the U-phase coil, and FIG. 16(C) is a perspective view
illustrating a combination of these winding portions.
FIG. 17 is a perspective view illustrating the U-phase coil
of a stator of the second embodiment.
FIGS. 18(A) to 18(C) are schematic diagrams for explaining 25 a method of forming coil segments of the second embodiment.
FIG. 19 is a flowchart illustrating a manufacturing method
of the stator of the second embodiment.
FIG. 20 is a cross-sectional view illustrating a motor of a
third embodiment. 30 FIG. 21 is a perspective view illustrating a rotor of the
motor of the third embodiment.
FIG. 22 is a longitudinal cross-sectional view illustrating
a compressor to which the motor of any one of the first to third
6
embodiments is applicable.
FIG. 23 is a diagram illustrating an air conditioner that
includes the compressor illustrated in FIG. 22.
MODE FOR CARRYING OUT THE INVENTION
[0009] 5 FIRST EMBODIMENT
(Configuration of Motor)
FIG. 1 is a cross-sectional view illustrating a motor 100
of a first embodiment. The motor 100 is a synchronous motor and
is used, for example, in a compressor 300 (FIG. 22) which will be 10 described later. The motor 100 is a permanent magnet embedded
motor that has permanent magnets 55 embedded in a rotor 5.
[0010]
The motor 100 has a stator 1 and the rotor 5 rotatably
provided inside the stator 1. An air gap is provided between the 15 stator 1 and the rotor 5.
[0011]
The rotor 5 has a cylindrical rotor core 50 and permanent
magnets 55 attached to the rotor core 50. The rotor core 50 is
composed of electromagnetic steel sheets, each having a thickness 20 of, for example, 0.1 mm to 0.7 mm, which are stacked in the
direction of a rotation axis and integrally fixed together by
crimping or the like. The rotor core 50 has a cylindrical shape.
The rotor core 50 has end surfaces 15 and 16 (the end surface 16
is shown in FIG. 7) on both ends in the direction of the rotation 25 axis.
[0012]
The rotor core 50 has a circular shaft hole 53 formed at
its center in the radial direction. A shaft 56, which is a
rotation shaft, is fixed into the shaft hole 53 by press-fitting. 30 An axis C1, which is a central axis of the shaft 56, serves as
the rotation axis of the rotor 5.
[0013]
Hereinafter, a direction of the axis C1 of the shaft 56 is
7
referred to as an “axial direction”. A circumferential direction
(indicated by the arrow R1 in FIG. 1 and other figures) about the
axis C1 is referred to as a “circumferential direction”. A
radial direction about the axis C1 is referred to as a “radial
direction”. 5 [0014]
A plurality of magnet insertion holes 51 are formed along
an outer circumference of the rotor core 50 at equal intervals
in the circumferential direction. The number of magnet insertion
holes 51 is six in this example. Each magnet insertion hole 51 10 passes through the rotor core 50 in the axial direction. The
magnet insertion hole 51 extends linearly along the outer
circumferential surface of the rotor core 50.
[0015]
The permanent magnet 55 is disposed inside the magnet 15 insertion hole 51. The permanent magnet 55 is a flat plateshaped
member, and has a rectangular cross-sectional shape
perpendicular to the axial direction. The permanent magnet 55
has a width in the circumferential direction and has a thickness
in the radial direction. One permanent magnet 55 is disposed in 20 one magnet insertion hole 51. However, a plurality of permanent
magnets 55 may be disposed in one magnet insertion hole 51.
[0016]
The number of poles of the rotor 5 is the number of the
magnet insertion holes 51 and is six in this example. The number 25 of poles of the rotor 5 is not limited to six, but may be two or
more.
[0017]
A center of the magnet insertion hole 51 in the
circumferential direction is a pole center. In this example, the 30 magnet insertion hole 51 extends in a direction perpendicular to
a straight line in the radial direction that passes through the
pole center (also referred to as a magnetic pole centerline). A
portion between adjacent magnet insertion holes 51 is an inter8
pole portion.
[0018]
The permanent magnet 55 is made of a rare earth sintered
magnet that contains, for example, neodymium (Nd), iron (Fe) and
boron (B). The permanent magnet 55 is not limited to the rare 5 earth magnet and may be, for example, a ferrite magnet.
[0019]
Each permanent magnet 55 is magnetized so that its outer
side and inner side in the radial direction have opposite
magnetic poles. The permanent magnets 55 adjacent to each other 10 in the circumferential direction have opposite magnetic poles on
the outer circumferential side. The cross-sectional shape of the
permanent magnet 55 is not limited to the rectangular shape
described above and may be an arc-shape, for example.
[0020] 15 A flux barrier 52 is formed on each of both ends of the
magnet insertion hole 51 in the circumferential direction. The
flux barrier 52 is a hole for suppressing leakage magnetic flux
between adjacent magnetic poles (i.e., magnetic flux flowing
through the inter-pole portion). 20 [0021]
(Configuration of Stator)
FIG. 2 is a cross-sectional view illustrating the stator 1.
The stator 1 has a stator core 10 and coils 2 wound on the stator
core 10 in wave winding. The stator core 10 is composed of 25 electromagnetic steel sheets, each having a thickness of, for
example, 0.1 mm to 0.7 mm, which are stacked in the axial
direction and integrally fixed together by crimping or the like.
[0022]
FIG. 3 is a plan view illustrating the stator core 10. The 30 stator core 10 has an annular yoke 11 and a plurality of teeth 12
extending inward in the radial direction from the yoke 11. In an
example illustrated in FIG. 1, the number of teeth 12 is 18.
Each tooth 12 has a tip end portion 12a on its inner side in the
9
radial direction, and the tip end portion 12a faces the outer
circumferential surface of the rotor 5.
[0023]
A slot 13 is formed between the teeth 12 adjacent to each
other in the circumferential direction. The slot 13 is a portion 5 in which the coil 2 wound around the tooth 12 is accommodated.
The number of slots 13 (i.e., slot number) is the same as the
number of teeth 12, and is 18 in this example. A not shown
insulating portion is provided between the slot 13 and the coil 2.
[0024] 10 With reference to FIG. 2, the coils 2 wound on the stator
core 10 include a U-phase coil 21 as a first coil, a V-phase coil
22 as a second coil, and a W-phase coil 23 as a third coil.
[0025]
Each of the U-phase coil 21, the V-phase coil 22, and the 15 W-phase coil 23 is disposed annularly about the axis C1.
Positions of the U-phase coil 21, the V-phase coil 22 and the Wphase
coil 23 in the radial direction are different from each
other. More specifically, the U-phase coil 21 is located
outermost in the radial direction, the V-phase coil 22 is located 20 inside the U-phase coil 21 in the radial direction, and the Wphase
coil 23 is located innermost in the radial direction.
[0026]
The U-phase coil 21 has six U-phase winding portions 21A,
21B, 21C, 21D, 21E, and 21F in the circumferential direction. 25 The V-phase coil 22 has six V-phase winding portions 22A, 22B,
22C, 22D, 22E, and 22F in the circumferential direction. The Wphase
coil 23 has six W-phase winding portions 23A, 23B, 23C, 23D,
23E, and 23F in the circumferential direction.
[0027] 30 The term “winding portion” refers to a portion including
two slot insertion portions inserted into the slots 13 (for
example, straight portions 211 and 212 to be described later) and
at least one coil end (for example, a coil end 213 to be
10
described later).
[0028]
The number of winding portions per phase, i.e., the number
of winding portions of each of the U-phase coil 21, V-phase coil
22 and W-phase coil 23, corresponds to the number of poles of the 5 stator 1. The number of poles of the stator 1 is the number of
magnetic fields respectively generated by the coils 21, 22 and 23.
In a synchronous motor, the number of poles of the stator 1 is
the same as the number of poles of the rotor 5. In this example,
the number of poles of the stator 1 is six. 10 [0029]
A value obtained by dividing the number of slots by the
product of the number of poles and the number of phases is
referred to as the number of slots per pole per phase (NSPP).
When the number of slots is 18, the number of poles is six, and 15 the number of phases is three, the number of slots per phase per
pole is 1.
[0030]
FIG. 4 is a plan view illustrating the stator core 10 and
the coils 2 (i.e., the U-phase coil 21, the V-phase coil 22, and 20 the W-phase coil 23). The U-phase winding portions 21A to 21F
are arranged every three slots in the circumferential direction.
Each of the U-phase winding portions 21A to 21F is wound to span
three teeth 12. A coil pitch is 60 degrees (mechanical angle),
i.e., three slots. 25 [0031]
More specifically, the U-phase winding portion 21A has a
straight portion (i.e., slot insertion portion) 211 inserted into
one slot 13 and a straight portion (i.e., slot insertion portion)
212 inserted into a third slot 13 from the above-described slot 30 13 in the clockwise direction in the figure.
[0032]
The U-phase winding portion 21B has a straight portion 211
inserted into the slot 13 which is the same as the slot 13 into
11
which the straight portion 212 of the U-phase winding portion 21A
is inserted, and a straight portion 212 inserted into a third
slot 13 from the above-described slot 13 in the clockwise
direction in the figure.
[0033] 5 The U-phase winding portion 21C has a straight portion 211
inserted into the slot 13 which is the same as the slot 13 into
which the straight portion 212 of the U-phase winding portion 21B
is inserted, and a straight portion 212 inserted into a third
slot 13 from the above-described slot 13 in the clockwise 10 direction in the figure.
[0034]
The U-phase winding portions 21D, 21E, and 21F are arranged
in the same manner. Thus, the straight portion 212 of the Uphase
winding portion 21F is inserted into the same slot 13 as 15 the slot 13 into which the straight portion 211 of the U-phase
winding portion 21A is inserted.
[0035]
Among these U-phase winding portions 21A to 21F, the Uphase
winding portions 21A, 21C, and 21E (the first winding 20 portions) are located on the outer side in the radial direction
with respect to the U-phase winding portions 21B, 21D, and 21F
(the second winding portions).
[0036]
The V-phase winding portions 22A to 22F are arranged every 25 three slots in the circumferential direction. Each of the Vphase
winding portions 22A to 22F is wound to span three teeth 12.
A coil pitch is 60 degrees (mechanical angle), i.e., three slots.
[0037]
More specifically, the V-phase winding portion 22A has a 30 straight portion 221 inserted into a slot 13 adjacent
counterclockwise in the figure to the slot 13 into which the
straight portion 211 of the U-phase winding portion 21A is
inserted, and a straight portion 222 inserted into a third slot
12
13 from the above-described slot 13 in the clockwise direction in
the figure.
[0038]
The V-phase winding portion 22B has a straight portion 221
inserted into the slot 13 which is the same as the slot 13 into 5 which the straight portion 222 of the V-phase winding portion 22A
is inserted, and a straight portion 222 inserted into a third
slot 13 from the above-described slot 13.
[0039]
The V-phase winding portion 22C has a straight portion 221 10 inserted into the slot 13 which is the same as the slot 13 into
which the straight portion 222 of the V-phase winding portion 22B
is inserted, and a straight portion 222 inserted into a third
slot 13 from the above-described slot 13.
[0040] 15 The V-phase winding portions 22D, 22E, and 22F are also
arranged in the same manner. Thus, the straight portion 222 of
the V-phase winding portion 22F is inserted into the same slot 13
as the slot 13 into which the straight portion 221 of the V-phase
winding portion 22A is inserted. 20 [0041]
Among these V-phase winding portions 22A to 22F, the Vphase
winding portions 22A, 22C, and 22E (the first winding
portions) are located on the outer side in the radial direction
with respect to the V-phase winding portions 22B, 22D, and 22F 25 (the second winding portions).
[0042]
The W-phase winding portions 23A to 23F are arranged every
three slots in the circumferential direction. Each of the Wphase
winding portions 23A to 23F is wound to span three teeth 12. 30 A coil pitch is 60 degrees (mechanical angle), i.e., three slots.
[0043]
More specifically, the W-phase winding portion 23A has a
straight portion 231 inserted into a slot 13 adjacent
13
counterclockwise in the figure to the slot 13 into which the
straight portion 221 of the V-phase winding portion 22A is
inserted and a straight portion 232 inserted into a third slot 13
from the above-described slot 13 in the clockwise direction in
the figure. 5 [0044]
The W-phase winding portion 23B has a straight portion 231
inserted into the slot 13 which is the same as the slot 13 into
which the straight portion 232 of the W-phase winding portion 23A
is inserted, and a straight portion 232 inserted into a third 10 slot 13 from the above-described slot 13.
[0045]
The W-phase winding portion 23C has a straight portion 231
inserted into the slot 13 which is the same as the slot 13 into
which the straight portion 232 of the W-phase winding portion 23B 15 is inserted, and a straight portion 232 inserted into a third
slot 13 counted from the above-described slot 13.
[0046]
The W-phase winding portions 23D, 23E, and 23F are arranged
in the same manner. Thus, the straight portion 232 of the W- 20 phase winding portion 23F is inserted into the same slot 13 as
the slot 13 into which the straight portion 231 of the W-phase
winding portion 23A is inserted.
[0047]
Among these W-phase winding portions 23A to 23F, the W- 25 phase winding portions 23A, 23C, and 23E (the first winding
portions) are located on the outer side in the radial direction
with respect to the W-phase winding portions 23B, 23D, and 23F
(the second winding portions).
[0048] 30 FIG. 5 is a plan view illustrating the stator core 10, the
coils 2, and insulating films 41 and 42. The insulating film 41
is disposed between the U-phase coil 21 and the V-phase coil 22
so as to electrically insulate the coils 21 and 22. The
14
insulating film 42 is disposed between the V-phase coil 22 and
the W-phase coil 23 so as to electrically insulate the coils 22
and 23.
[0049]
Each of the insulating films 41 and 42 is made of an 5 insulating resin such as polyethylene terephthalate (PET). Each
of the insulating films 41 and 42 is a strip-shaped film that has
a width in the axial direction, and is disposed on the end
surface 15 of the stator core 10.
[0050] 10 The insulating film 41 is located between the U-phase coil
21 and the V-phase coil 22 in the radial direction and is
disposed annularly about the axis C1. One end 411 and the other
end 412 of the insulating film 41 in the longitudinal direction
overlap each other and are fixed together. 15 [0051]
The insulating film 42 is located between the V-phase coil
22 and the W-phase coil 23 in the radial direction and is
disposed annularly about the axis C1. One end 421 and the other
end 422 of the insulating film 42 in the longitudinal direction 20 overlap each other and are fixed together.
[0052]
Although FIG. 5 illustrates the insulating films 41 and 42
on one end surface 15 of the stator core 10, another insulating
film 41 and another insulating film 42 are arranged on the other 25 end surface 16 (FIG. 7) of the stator core 10. That is, the Uphase
coil 21, the V-phase coil 22, and the W-phase coil 23 can
be electrically insulated from one another with a total of four
insulating films 41 and 42.
[0053] 30 FIG. 6(A) is a perspective view illustrating the U-phase
winding portions 21A, 21C, and 21E, and FIG. 6(B) is a
perspective view illustrating the U-phase winding portions 21B,
21D, and 21F. FIG. 6(C) is a perspective view illustrating the
15
U-phase wiring portions 21A to 21F.
[0054]
As shown in FIG. 6(A), the U-phase winding portions 21A,
21C, and 21E are arranged at intervals of 120 degrees about the
axis C1. Each of the U-phase winding portions 21A, 21C, and 21E 5 has the straight portions 211 and 212 extending in the axial
direction, the coil end 213 connecting one end of the straight
portion 211 and one end of the straight portion 212 (upper ends
of the straight portions shown in the figure), and a coil end 214
connecting the other end of the straight portion 211 and the 10 other end of the straight portion 212 (lower ends of the straight
portions in the figure). Each of the straight portions 211 and
212 and the coil ends 213 and 214 is composed of a bundle of
copper wires.
[0055] 15 As shown in FIG. 6(B), the U-phase winding portions 21B,
21D, and 21F are arranged at intervals of 120 degrees in the
circumferential direction. Each of the U-phase winding portions
21B, 21D, and 21F has the straight portions 211 and 212 extending
in the axial direction, the coil end 213 connecting one end of 20 the straight portion 211 and one end of the straight portion 212
(upper ends of the straight portions shown in the figure), and
the coil end 214 connecting the other end of the straight portion
211 and the other end of the straight portion 212 (lower ends of
the straight portions in the figure). Each of the straight 25 portions 211 and 212 and the coil ends 213 and 214 is composed of
a bundle of copper wires.
[0056]
As shown in FIG. 6(C), the U-phase winding portions 21A to
21F are arranged at intervals of 60 degrees in the 30 circumferential direction, and the U-phase winding portions 21A,
21C, and 21E are located on the outer side in the radial
direction with respect to the U-phase winding portions 21B, 21D,
and 21F. That is, the straight portions 211 and 212 of the U16
phase winding portions 21A, 21C, and 21E are located on the inner
side in the radial direction with respect to the straight
portions 221 and 222 of the U-phase winding portions 21B, 21D,
and 21F.
[0057] 5 The U-phase winding portions 21B, 21D, and 21F have lengths
in the axial direction (i.e., lengths of the straight portions
211 and 212) longer than lengths of the U-phase winding portions
21A, 21C, and 21E in the axial direction. In other words, the Uphase
winding portions 21B, 21D, and 21F protrude on both sides 10 in the axial direction from the U-phase winding portions 21A, 21C,
and 21E.
[0058]
FIG. 7 is a perspective view illustrating a state in which
the U-phase winding portions 21A to 21F are wound on the stator 15 core 10. The U-phase winding portions 21A to 21F are previously
wound in the shapes illustrated in FIGS. 6(A) and 6(B) and then
inserted into the slots 13 of the stator core 10 by a known
inserter.
[0059] 20 The inserter is an automatic winding apparatus that has
pawls of the same number as the slots 13. The winding portions
of the coils are hung over the pawls, and the pawls are moved
along the tip end portions 12a of the teeth 12 from one side in
the axial direction, so that the winding portions are 25 accommodated inside the slots 13.
[0060]
The straight portions 211 and 212 of the U-phase winding
portions 21A, 21C, and 21E are disposed on the outer side in the
radial direction in the slots 13. The straight portions 211 and 30 212 of the U-phase winding portions 21B, 21D, and 21F are
disposed on the inner side in the radial direction with respect
to the straight portions 211 and 212 of the U-phase winding
portions 21A, 21C, and 21E in the slots 13.
17
[0061]
The coil ends 213 of the U-phase winding portions 21A to
21F extend in the circumferential direction on the end surface 15
of the stator core 10, while the coil ends 214 of the U-phase
winding portions 21A to 21F extend in the circumferential 5 direction on the end surface 16 of the stator core 10.
[0062]
Since the U-phase winding portions 21A, 21C, and 21E are
located on the outer side in the radial direction with respect to
the U-phase winding portions 21B, 21D, and 21F, it is possible to 10 first insert the U-phase winding portions 21A, 21C, and 21E into
the slots 13 and then insert the U-phase winding portions 21B,
21D, and 21F into the slots 13.
[0063]
In this example, since two adjacent winding portions (for 15 example, the U-phase winding portions 21A and 21B) are inserted
in the same slot 13, the winding portions in the same slot 13 may
interfere with each other, if the U-phase winding portions 21A to
21F are inserted into the slots 13 at the same time. By first
inserting the U-phase winding portions 21A, 21C, and 21E into the 20 slots 13 and then inserting the U-phase winding portions 21B, 21D,
and 21F into the slots 13, the interference between the winding
portions in the same slot 13 can be avoided.
[0064]
Two straight portions to be inserted into the same slot 13 25 (for example, the straight portion 212 of the U-phase winding
portion 21A and the straight portion 211 of the U-phase winding
portion 21B) may be located in the same position in the
circumferential direction as illustrated in FIG. 7, or may be
displaced in the circumferential direction as illustrated in FIGS. 30 4 and 5.
[0065]
FIG. 8 is a plan view illustrating a state in which the
coil ends 213 of the U-phase winding portions 21A to 21F are
18
deformed outward in the radial direction from the state
illustrated in FIG. 7. As described above, the lengths of the Uphase
winding portions 21B, 21D, and 21F in the axial direction
are longer than the lengths of the U-phase winding portions 21A,
21C, and 21E in the axial direction. 5 [0066]
Therefore, when the coil ends 213 of the U-phase winding
portions 21B, 21D, and 21F are deformed outward in the radial
direction, the position in the radial direction of each of the
coil ends 213 of the U-phase winding portions 21B, 21D, and 21F 10 is the same as the position in the radial direction of each of
the coil ends 213 of the U-phase winding portions 21A, 21C, and
21E. In other words, the six coil ends 213 of the U-phase
winding portions 21A to 21F are aligned annularly.
[0067] 15 FIG. 8 illustrates the coil ends 213 on one end surface 15
of the stator core 10, but the same can be applied to the coil
ends 214 on the other end surface 16 (FIG. 7).
[0068]
Since the length of each of the U-phase winding portions 20 21B, 21D, and 21F in the axial direction is longer than the
length of each of the U-phase winding portions 21A, 21C, and 21E
in the axial direction, the average circumference length of each
of the U-phase winding portions 21B, 21D, and 21F is longer than
the average circumference length of each of the U-phase winding 25 portions 21A, 21C, and 21E.
[0069]
In this case, if the cross-sectional area of each of the Uphase
winding portions 21A, 21C, and 21E is equal to the crosssectional
area of each of the U-phase winding portions 21B, 21D, 30 and 21F, the electrical resistance of each of the U-phase winding
portions 21A, 21C, and 21E is different from the electrical
resistance of each of the U-phase winding portions 21B, 21D, and
21F.
19
[0070]
Therefore, in this example, the cross-sectional area S1 of
each of the U-phase winding portions 21A, 21C, and 21E is made
smaller than the cross-sectional area S2 of each of the U-phase
winding portions 21B, 21D, and 21F. The electrical resistance is 5 proportional to the circumference length, but inversely
proportional to the cross-sectional area. Thus, the crosssectional
area S1 of each of the U-phase winding portions 21A,
21C, and 21E having shorter average circumference lengths are
made smaller than the cross-sectional area S2 of each of the U- 10 phase winding portions 21B, 21D, and 21F having longer average
circumference lengths. Accordingly, the electrical resistance of
each of the U-phase winding portions 21A, 21C, and 21E can be
made closer to the electrical resistance of each of the U-phase
winding portions 21B, 21D, and 21F. 15 [0071]
Since each of the winding portions 21A to 21F is composed
of a bundle of copper wires, each of the cross-sectional areas S1
and S2 is the sum of the cross-sectional areas of the bundle of
copper wires in the slot 13. The above-mentioned relationship 20 between the cross-sectional areas S1 and S2 (S1 < S2) can also be
rephrased that a space factor of each of the U-phase winding
portions 21A, 21C, and 21E in the slot 13 is less than a space
factor of each of the U-phase winding portions 21B, 21D, and 21F
in the slot 13. 25 [0072]
FIGS. 6(A) to 8 illustrate the U-phase winding portions 21A
to 21F, but the V-phase winding portions 22A to 22F and the Wphase
winding portions 23A to 23F are also arranged in the same
manner as the U-phase winding portions 21A to 21F. In FIGS. 1 30 and 2 described above, the cross sections of the coils 21, 22,
and 23 at the coil ends 213 are illustrated.
[0073]
FIG. 9(A) illustrates the connected state of the U-phase
20
coil 21, the V-phase coil 22, and the V-phase coil 23. The Uphase
coil 21, the V-phase coil 22 and the V-phase coil 23 are
connected to each other by Y-connection.
[0074]
That is, the U-phase coil 21 has one terminal 205 connected 5 to a wiring 202 and the other terminal connected to a neutral
point 208. The V-phase coil 22 has one terminal 206 connected to
a wiring 203 and the other terminal connected to the neutral
point 208. The W-phase coil 23 has one terminal 207 connected to
a wiring 204 and the other terminal connected to the neutral 10 point 208. The wirings 202, 203, and 204 are connected to an
inverter 201 that drives the motor 100.
[0075]
FIG. 9(B) is a diagram illustrating an example of the
connected state of the U-phase wiring portions 21A to 21F. In 15 this example, a pair of U-phase winding portions 21A and 21B
connected in series, a pair of U-phase winding portions 21C and
21D connected in series, and a pair of U-phase winding portions
21E and 21F connected in series are all connected in parallel.
[0076] 20 The example illustrated in FIG. 9(B) is one of examples.
As another example, a group of U-phase winding portions 21A, 21C,
and 21E connected in series and a group of U-phase winding
portions 21B, 21D, and 21F connected in series may be connected
in parallel. 25 [0077]
(Manufacturing Method of Stator)
Next, a manufacturing method of the stator 1 will be
described. FIG. 10 is a flowchart illustrating a manufacturing
process of the stator 1. FIG. 11 includes plan views 30 illustrating steps of a winding process of the coils 2. First, a
plurality of electromagnetic steel sheets are stacked in the
axial direction and integrally fixed together by crimping or the
like to thereby obtain the stator core 10 illustrated in FIG. 3
21
(step S101).
[0078]
Then, the U-phase winding portions 21A, 21C, and 21E are
inserted into the slots 13 of the stator core 10 by the inserter
(step S102). As illustrated in FIG. 11(A), the U-phase winding 5 portions 21A, 21C, and 21E are inserted into the outermost side
(back side) in the slots 13 in the radial direction. The coil
ends 213 of the U-phase winding portions 21A, 21C, and 21E are
deformed outward in the radial direction as indicated by hatching
in the figure. 10 [0079]
Then, the U-phase winding portions 21B, 21D, and 21F are
inserted into the slots 13 of the stator core 10 (step S103). As
illustrated in FIG. 11(B), the U-phase winding portions 21B, 21D,
and 21F are inserted on the inner side (front side) in the radial 15 direction with respect to the U-phase winding portions 21A, 21C,
and 21E in the slots 13. The coil ends 213 of the U-phase
winding portions 21B, 21D, and 21F are deformed outward in the
radial direction as indicated by hatching in the figure.
Subsequently, the insulating film 41 illustrated in FIG. 5 is 20 disposed on the inner side of the U-phase winding portions 21A to
21F in the radial direction.
[0080]
Then, the V-phase winding portions 22A, 22C, and 22E are
inserted into the slots 13 of the stator core 10 (step S104). As 25 illustrated in FIG. 11(C), the V-phase winding portions 22A, 22C,
and 22E are inserted into the slots 13 adjacent in the
counterclockwise direction to the slots 13 into which the U-phase
winding portions 21A to 21F are inserted. The coil ends 223 of
the V-phase winding portions 22A, 22C, and 22E are deformed 30 outward in the radial direction as indicated by hatching in the
figure.
[0081]
Then, the V-phase winding portions 22B, 22D, and 22F are
22
inserted into the slots 13 of the stator core 10 (step S105). As
illustrated in FIG. 11(D), the V-phase winding portions 22B, 22D,
and 22F are inserted on the inner side (front side) in the radial
direction with respect to the V-phase winding portions 22A, 22C,
and 22E in the slots 13. The coil ends 223 of the V-phase 5 winding portions 22B, 22D, and 22F are deformed outward in the
radial direction as indicated by hatching in the figure.
Subsequently, the insulating film 42 illustrated in FIG. 5 is
disposed on the inner side of the V-phase winding portions 22A to
22F in the radial direction. 10 [0082]
Then, the W-phase winding portions 23A, 23C, and 23E are
inserted into the slots 13 of the stator core 10 (step S106). As
illustrated in FIG. 11(E), the W-phase winding portions 23A, 23C,
and 23E are inserted into the slots 13 adjacent in the 15 counterclockwise direction to the slots 13 into which the V-phase
winding portions 22A to 22F are inserted. The coil ends 234 of
the W-phase winding portions 23A, 23C, and 23E are deformed
outward in the radial direction as indicated by hatching in the
figure. 20 [0083]
Then, the W-phase winding portions 23B, 23D, and 23F are
inserted into the slots 13 of the stator core 10 (step S107). As
illustrated in FIG. 11(F), the W-phase winding portions 23B, 23D,
and 23F are inserted on the inner side (front side) in the radial 25 direction with respect to the W-phase winding portions 23A, 23C,
and 23E in the slots 13. The coil ends 234 of the W-phase
winding portions 23B, 23D, and 23F are deformed outward in the
radial direction as indicated by hatching in the figure.
[0084] 30 As above, the insertion of the U-phase coil 21, the V-phase
coil 22, and the W-phase coil 23 into the slots 13 of the stator
core 10 is completed.
[0085]
23
Then, the coil ends 213, 223, and 233 of the coils 21, 22,
and 23 are subjected to a shaping process (i.e., are shaped)
(step S108). Then, the U-phase coil 21, the V-phase coil 22 and
the W-phase coil 23 are connected as illustrated in FIG. 9(A) and
9(B) (step S109). Consequently, the manufacturing of the stator 5 1 is completed.
[0086]
In the process described herein, each of the U-phase coil
21, the V-phase coil 22, and the W-phase coil 23 is inserted into
the slots 13 in two stages. However, each of the U-phase coil 21, 10 the V-phase coil 22 and the W-phase coil 23 may be inserted into
the slots 13 in one stage in the case where the interference
between the winding portions is less likely to occur in the slots
13.
[0087] 15 FIG. 12 is a flowchart illustrating another example of the
manufacturing method of the stator 1. First, in the same manner
as in step S101 illustrated in FIG. 10, a plurality of
electromagnetic steel sheets are stacked in the axial direction
and integrally fixed together by crimping or the like to thereby 20 obtain the stator core 10 (step S111).
[0088]
Then, the U-phase winding portions 21A to 21F are inserted
into the slots 13 of the stator core 10 (step S112). The coil
ends 213 of the U-phase winding portions 21A to 21F are deformed 25 outward in the radial direction. Subsequently, the insulating
film 41 illustrated in FIG. 5 is disposed on the inner side of
the U-phase winding portions 21A to 21F in the radial direction.
[0089]
Then, the V-phase winding portions 22A to 22F are inserted 30 into the slots 13 of the stator core 10 (step S113). The coil
ends 223 of the V-phase winding portions 22A to 22F are deformed
outward in the radial direction. Subsequently, the insulating
film 42 illustrated in FIG. 5 is disposed on the inner side of
24
the V-phase winding portions 22A to 22F in the radial direction.
[0090]
Then, the W-phase winding portions 23A to 23F are inserted
into the slots 13 of the stator core 10 (step S114). The coil
ends 223 of the V-phase winding portions 22A to 22F are deformed 5 outward in the radial direction. As above, the insertion of the
U-phase coil 21, the V-phase coil 22, and the W-phase coil 23
into the slots 13 of the stator core 10 is completed.
[0091]
Subsequently, in the same manner as in steps S108 and S109 10 illustrated in FIG. 10, the coil ends 213, 223, and 233 are
shaped (step S115), and then the U-phase coil 21, the V-phase
coil 22, and the W-phase coil 23 are connected (step S116).
Consequently, the manufacturing of the stator 1 is completed.
[0092] 15 (Operation)
Next, the operation of the first embodiment will be
described. First, Comparative Examples 1 to 3 to be compared
with the first embodiment will be described with reference to
FIGS. 13 to 15. For convenience of description, some components 20 of Comparative Examples are denoted with the same reference signs
as the components of the first embodiment.
[0093]
FIG. 13 is a diagram illustrating a motor of Comparative
Example 1. The motor of Comparative Example 1 has a stator 1A 25 and a rotor 5A rotatably provided on an inner side of the stator
1A.
[0094]
The rotor 5A has a rotor core 50. The rotor core 50 has
six magnet insertion holes 51A along the outer circumference of 30 the rotor core 50, has a flux barrier 52 on each of both sides of
the magnet insertion hole 51A in the circumferential direction,
and has the shaft hole 53 at the center of the rotor core 50 in
the radial direction. Each magnet insertion hole 51A has a V
25
shape with its center in the circumferential direction protruding
inward in the radial direction. Two permanent magnets 55 are
disposed in each magnet insertion hole 51A. A plurality of slits
54 are formed on the outer side in the radial direction with
respect to the magnet insertion holes 51A of the rotor core 50. 5 The shaft 56 is fixed to the shaft hole 53.
[0095]
The stator 1A has a stator core 10A, U-phase winding
portions 71 (a U-phase coil), V-phase winding portions 72 (a Uphase
coil), and W-phase winding portions 73 (a W-phase coil), 10 all of which are wound on the stator core 10A. The stator core
10A has 18 teeth 12 in the circumferential direction and 18 slots
13.
[0096]
The U-phase winding portions 71 are arranged every six 15 slots in the circumferential direction. The number of U-phase
winding portions 71 is three. Each U-phase winding portion 71 is
wound to span three teeth 12. A coil pitch of the U-phase
winding portions 71 is 60 degrees (mechanical angle), i.e., three
slots. The W-phase winding portions 73 are located on the inner 20 side in the radial direction with respect to the U-phase winding
portions 71. The W-phase winding portions 73 are arranged every
six slots in the circumferential direction. The number of Wphase
winding portions is three. Each W-phase winding portion 72
is wound to span three teeth 12. A coil pitch of the W-phase 25 portions 72 is 60 degree (mechanical angle), i.e., three slots.
[0097]
The V-phase winding portions 72 are arranged every six
slots in the circumferential direction. The number of V-phase
winding portions 71 is three. Each V-phase winding portion 72 is 30 wound to span three teeth 12. A coil pitch of the V-shaped
winding portions 72 is 60 degrees (mechanical angle), i.e., three
slots. Each V-phase winding portion 72 extends from the inner
side of the U-phase winding portion 71 in the radial direction to
26
the outer side of the W-phase winding portion 73 in the radial
direction.
[0098]
In Comparison Example 1, the number of slots is 18, the
number of poles is six, and the number of phases is three. Thus, 5 the number of slots per phase per pole is 1. However, since the
number of phases is three and the number of winding portions 71
to 73 is nine, the number of winding portions per phase is as low
as three. Thus, the coil ends of each winding portion increase
in size. As a result, the circumference length of each winding 10 portion increases, and the electrical resistance (i.e., loss)
increases, which reduces the motor efficiency.
[0099]
FIG. 14 is a diagram illustrating a motor of Comparative
Example 2. The motor of Comparative Example 2 has a stator 1B 15 and a rotor 5A rotatably provided on an inner side of the stator
1B. The configuration of the rotor 5A is the same as that of
Comparative Example 1 illustrated in FIG. 13.
[0100]
The stator 1B has a stator core 10B, U-phase winding 20 portions 81 (a U-phase coil), V-phase winding portions 82 (a Vphase
coil), and W-phase winding portions 83 (a V-phase coil),
all of which are wound on the stator core 10B. The stator core
10B has 36 teeth 12 in the circumferential direction and 36 slots
13. 25 [0101]
The U-phase winding portions 81 are arranged every six
slots in the circumferential direction. The number of U-phase
winding portions 81 is six. Each U-phase winding portion 81
spans five teeth 12. A coil pitch of the U-phase winding 30 portions 81 corresponds to five slots. The V-phase winding
portions 82 are disposed on the inner side in the radial
direction with respect to the U-phase winding portions 81, and
the W-phase winding portions 83 are disposed on the inner side in
27
the radial direction with respect to the V-phase winding portions
82. Both the V-phase winding portions 82 and the W-phase winding
portions 83 are wound in the same manner as the U-phase winding
portions 81.
[0102] 5 In Comparison Example 2, the number of slots is 36, the
number of poles is six, and the number of phases is three, so
that the number of slots per phase per pole is 2. Since the
number of winding portions per phase is as large as 12, the coil
ends can be reduced in size. However, the number of slots per 10 pole is six, whereas the coil pitch of the winding portions 81 to
83 is five slots, so that a winding factor Kw is smaller than 1.
When the winding factor Kw is smaller than 1, the usage
efficiency of magnetic flux of the permanent magnets 55 in the
rotor 5 is reduced. 15 [0103]
FIG. 15 is a diagram illustrating a stator 1C of a motor of
Comparative Example 3. The stator 1C of Comparative Example 3
has a stator core 10C, U-phase winding portions 91 (i.e., a Uphase
coil), V-phase winding portions 92 (i.e., a V-phase coil), 20 and W-phase winding portions 93 (i.e., a W-phase coil), all of
which are wound on the stator core 10C. The stator core 10C has
24 teeth 12 and 24 slots 13 in the circumferential direction.
[0104]
The U-phase winding portions 91 are inserted every three 25 slots in the circumferential direction. Similarly, the V-phase
winding portions 92 are inserted every three slots in the
circumferential direction, and the W-phase winding portions 93
are also inserted every three slots in the circumferential
direction. 30 [0105]
The U-phase winding portions 91, the V-phase winding
portions 92, and the W-phase winding portions 93 are wound by lap
winding. More specifically, each U-phase winding portion 91 is
28
wound spirally so as to pass through the inner side in the radial
direction in the slot 13 and the outer side in the radial
direction in a third slot 13 from the above-described slot 13.
The V-phase winding portions 92 and the W-phase winding portions
93 are wound spirally in the same manner as the U-phase winding 5 portions 91.
[0106]
In Comparison Example 3, the number of slots is 24, the
number of poles is eight, and the number of phases is three, so
that the number of slots per phase per pole is 1. The number of 10 winding portions per phase is as large as 12, and thus the coil
ends can be reduced in size. The winding factor Kw is 1.
However, the winding portions 91 to 93 are all wound spirally, a
large number of insulating films need to be provided so as to
insulate the winding portions 91 to 93 from each other. Further, 15 the work to spirally wind the winding portions 91 to 93 is
complicated, and thus the manufacturing cost is increased.
[0107]
As compared with Comparative Examples 1 to 3, the operation
of the motor 100 of the first embodiment will be described. In 20 Comparative Example 1 (FIG. 13) described above, the number of
winding portions per phase is small and thus the coil ends are
enlarged. In contrast, in the first embodiment, each of the
coils 21, 22, and 23 has the winding portions (for example, the
U-phase winding portions 21A to 21F), the number of which is the 25 same as the number of poles, and the winding portions are
arranged dispersedly in the circumferential direction.
Consequently, the coil ends can be reduced in size, and the use
amount of copper wires can be reduced, so that the manufacturing
cost can be reduced. 30 [0108]
By reducing the size of the coil ends, the circumference
length of each of the coils 21, 22, and 23 can be shortened, and
thus the electrical resistance decreases and the loss is reduced.
29
This can improve the motor efficiency.
[0109]
In Comparative Example 2 (FIG. 14) described above, the
winding factor Kw is less than 1, and thus the magnetic flux of
the permanent magnets 55 in the rotor 5 cannot be efficiently 5 used. Here, the winding factor Kw is expressed as the product of
a short-pitch winding factor Kp and a distributed winding factor
Kd (i.e., Kw = Kp x Kd). The short-pitch winding factor Kp is
represented by the following equation (1) based on the number of
poles P, the number of slots S, and the coil throw T (the number 10 of teeth that the winding portion spans).
••• (1)
[0110]
The distributed winding factor Kd is represented by the
following equation (2) based on a phase difference α between the 15 winding portions.
••• (2)
[0111]
In the first embodiment, the number of poles P is 3, the
number of slots S is 18, and the coil throw T is 3, so that the 20 short-pitch winding factor Kp is determined to be 1 by equation
(1). Further, since the phase difference α between the winding
portions is 0, the distributed winding factor Kd is determined to
be 1 by equation (2). Consequently, the winding factor Kw, which
is the product of Kp and Kd, is 1. 25 [0112]
That is, the first embodiment achieves Kw = 1 not only by
disposing the U-phase coil 21, the V-phase coil 22, and the Wphase
coil 23 in different positions in the radial direction, but
also by inserting adjacent winding portions of the same phase 30 (for example, adjacent U-phase winding portions 21A and 21B) in
one slot 13. By setting the winding factor Kw to 1 in this way,
30
the magnetic flux of the permanent magnets 55 in the rotor 5 can
be used efficiently.
[0113]
In Comparative Example 3 (FIG. 15) described above, the
winding portions 91, 92, and 93 are wound spirally, and thus a 5 complex winding work and a number of insulating films are needed.
In contrast, in the first embodiment, the coils 21, 22, and 23
are each disposed annularly and are disposed in different
positions in the radial direction, and thus the coils 21, 22, and
23 can be inserted into the slots 13 using the inserter. Thus, 10 the manufacturing cost can be reduced.
[0114]
As the coils 21, 22, and 23 are each disposed annularly and
are disposed in different positions in the radial direction, the
coils 21, 22, and 23 can be insulated from each other by 15 disposing the insulating films 41 and 42 (FIG. 5) between the Uphase
coil 21 and the V-phase coil 22 and between the V-phase
coil 22 and the W-phase coil 23, respectively. In other words,
the number of parts can be reduce and thus the manufacturing cost
can be further reduced. 20 [0115]
(Effects of Embodiment)
As described above, in the first embodiment, the coils 21,
22, and 23 are wound on the stator core 10 in the distributed
winding, and the winding factor Kw is 1. Each of the coils 21, 25 22, and 23 has the winding portions (for example, the U-phase
winding portions 21A to 21F), the number of which is the same as
the number of poles. The first winding portion (for example, the
U-phase winding portion 21A) and the second winding portion (for
example, the U-phase winding portion 21B), which are adjacent to 30 each other in the circumferential direction, are inserted into
one slot 13, and extend from this slot 13 to both sides in the
circumferential direction at each of the end surfaces 15 and 16
of the stator core 10. The coils 21, 22, and 23 are each
31
annularly disposed and are disposed in different positions in the
radial direction on the end surface of the stator core 10.
[0116]
Since the coils 21, 22, and 23 are arranged dispersedly,
the coil ends can be reduced in size, and thus it is possible to 5 reduce the use amount of copper wires and reduce the
manufacturing cost. Further, the reduction in the weight and
size of the motor 100 can be achieved by reducing the size of the
coil ends. Moreover, the electrical resistance can be suppressed
to reduce the loss, and thus the motor efficiency can be improved. 10 Furthermore, by setting the winding factor Kw to 1, the magnetic
flux of the permanent magnets 55 in the rotor 5 can be used
efficiently, and thus the motor efficiency can be further
improved. In addition, the insertion of the coils 21, 22, and 23
into the slots 13 can be facilitated, and portions where the 15 insulating films 41 and 42 are attached are few, so that the
manufacturing cost can be further reduced.
[0117]
The first wiring portions (for example, the U-phase winding
portions 21A, 21C, and 21E) are disposed on the outer side in the 20 radial direction with respect to the second wiring portions (for
example, the U-phase winding portions 21B, 21D, and 21F), which
makes it possible to first insert the first winding portions into
the slots 13 and then insert the second winding portions into the
slots 13. Thus, the interference between the winding portions in 25 the slot 13 can be avoided.
[0118]
Since the average circumference length of each of the Uphase
winding portions 21B, 21D, and 21F (the second winding
portions) is longer than the average circumference length of each 30 of the U-phase winding portions 21A, 21C, and 21E (the first
winding portions), the coil ends of the first and second wiring
portions can be aligned annularly by deforming the first and
second winding portions outward in the radial direction.
32
[0119]
Further, since the space factor of the first winding
portion (for example, the U-phase winding portion 21A, 21C, or
21E) in the slot 13 is smaller than the space factor of the
second winding portion (for example, the U-phase winding portion 5 21B, 21D, or 21F) in the slot 13, the electrical resistances of
the first and second winding portions which have different
average circumference lengths can be made closer to each other.
[0120]
At the end surfaces 15 and 16 of the stator core 10, the 10 insulating film 41 is disposed between the U-phase coil 21 and
the V-phase coil 22, and the insulating film 42 is disposed
between the V-phase coil 22 and the W-phase coil 23. Thus, the
coils 21, 22, and 23 can be insulated from each other with a
small number of parts. 15 [0121]
For a synchronous motor, the permanent magnets 55 in a nonmagnetized
state may be attached to the stator core 10, and then
magnetization of the permanent magnets 55 may be performed by
applying a magnetic field from the stator 1. By arranging the 20 coils 21, 22, and 23 dispersedly, the electromagnetic force
acting among the coils 21, 22, and 23 during the magnetization of
the permanent magnets 55 can be reduced, and thus the damage
(deformation or the like) to the coil ends can be suppressed.
[0122] 25 Second Embodiment
Next, a second embodiment will be described. FIG. 16(A) is
a perspective view illustrating the U-phase winding portions 21A,
21C, and 21E of the second embodiment, and FIG. 16(B) is a
perspective view illustrating the U-phase winding portions 21B, 30 21D, and 21F of the second embodiment. FIG. 6(C) is a
perspective view illustrating the U-phase wiring portions 21A to
21F.
[0123]
33
As illustrated in FIG. 16(A), in the second embodiment,
each of the U-phase winding portions 21A, 21C, and 21E has
straight portions 211 and 212 and the coil end 213, and does not
have the coil end 214 (FIG. 6(A)).
[0124] 5 The straight portion 212 of the U-phase winding portion 21A
and the straight portion 211 of the U-phase winding portion 21C
are connected by a coil end 215, at an end (on the lower side in
the figure) opposite to the coil end 213. Similarly, the
straight portion 212 of the U-phase winding portion 21C and the 10 straight portion 211 of the U-phase winding portion 21E are
connected by a coil end 215, at an end opposite to the coil end
213. Further, the straight portion 212 of the U-phase winding
portion 21E and the straight portion 211 of the U-phase winding
portion 21A are connected by a coil end 215, at an end opposite 15 to the coil end 213.
[0125]
That is, the U-phase winding portions 21A, 21C, and 21E are
connected in series in a wave shape to constitute a coil segment
31 as a first segment. In other words, the coil segment 31 is 20 formed by connecting the winding portions (i.e., the U-phase
winding portions 21A, 21C, and 21E), the number of which is half
the number of poles, in the wave shape.
[0126]
As illustrated in FIG. 16(B), each of the U-phase winding 25 portions 21B, 21D, and 21F has the straight portions 211 and 212
and the coil end 213, and does not have the coil end 214 (FIG.
6(B)).
[0127]
The straight portion 212 of the U-phase winding portion 21B 30 and the straight portion 211 of the U-phase winding portion 21D
are connected by a coil end 215, at an end (on the lower side in
the figure) opposite to the coil end 213. Similarly, the
straight portion 212 of the U-phase winding portion 21D and the
34
straight portion 211 of the U-phase winding portion 21F are
connected by a coil end 215, at an end opposite to the coil end
213. Further, the straight portion 212 of the U-phase winding
portion 21F and the straight portion 211 of the U-phase winding
portion 21B are connected by a coil end 215 at an end opposite to 5 the coil end 213.
[0128]
That is, the U-phase winding portions 21B, 21D, and 21F are
connected in series in the wave shape to constitute a coil
segment 32 as a second segment. In other words, the coil segment 10 32 is formed by connecting the winding portions (i.e., the Uphase
winding portions 21B, 21D, and 21F), the number of which is
half the number of poles, in the wave shape.
[0129]
The U-phase coil 21 illustrated in FIG. 16(C) is obtained 15 by combining the coil segment 31 illustrated in FIG. 16(A) and
the coil segment 32 illustrated in FIG. 16(B). In the U-phase
coil 21, as in the first embodiment, the U-phase winding portions
21A to 21F are arranged at intervals of 60 degrees in the
circumferential direction. 20 [0130]
FIG. 17 is a perspective view of the U-phase coil 21
obtained in this way. In the U-phase coil 21, the coil segment
31 (i.e., the U-phase winding portions 21A, 21C, and 21E) is
located on the outer side in the radial direction with respect to 25 the coil segment 32 (i.e., the U-phase winding portions 21B, 21D,
and 21F).
[0131]
The coil end 213 of the U-phase winding portion 21A faces
the coil end 215 between the U-phase winding portions 21F and 21B 30 in the axial direction. Similarly, the coil end 213 of the Uphase
winding portion 21B faces the coil end 215 between the Uphase
winding portions 21A and 21C in the axial direction. The
coil end 213 of the U-phase winding portion 21C faces the coil
35
end 215 between the U-phase winding portions 21B and 21D in the
axial direction. The coil end 213 of the U-phase winding portion
21D faces the coil end 215 between the U-phase winding portions
21C and 21E in the axial direction. The coil end 213 of the Uphase
winding portion 21E faces the coil end 215 between the U- 5 phase winding portions 21D and 21F in the axial direction. The
coil end 213 of the U-phase winding portion 21F faces the coil
end 215 between the U-phase winding portions 21E and 21A in the
axial direction.
[0132] 10 When the U-phase coil 21 is inserted into the slots 13 of
the stator core 10, the state illustrated in FIG. 4 described
above is obtained. That is, the U-phase winding portions 21A to
21F of the U-phase coil 21 are arranged every three slots in the
circumferential direction. Each of the U-phase winding portions 15 21A to 21F is wound to span three teeth 12. A coil pitch is 60
degrees (mechanical angle), i.e., three slots.
[0133]
The U-phase winding portions adjacent to each other in the
circumferential direction (for example, the U-phase winding 20 portion 21A and the U-phase winding portion 21B) have the
straight portions (for example, the straight portion 212 of the
U-phase winding portion 21A and the straight portion 211 of the
U-phase winding portion 21B) inserted into the same slot 13, and
the coil ends 213 extend from this slot 13 to both sides in the 25 circumferential direction.
[0134]
Although FIGS. 16(A) to 16(C) and FIG. 17 illustrate the Uphase
coil 21, each of the V-phase coil 22 and the W-phase coil
23 is composed of two coil segments 31 and 32 in a similar manner 30 to the U-phase coil 21. As described in the first embodiment,
the V-phase coil 22 is disposed on the inner side in the radial
direction with respect to the U-phase coil 21, and the W-phase
coil 23 is disposed on the inner side in the radial direction
36
with respect to the V-phase coil 22. Both the number of slots
per phase per pole and the winding factor Kw are as described in
the first embodiment.
[0135]
In the second embodiment, since each of the coils 21, 22, 5 and 23 is composed of two coil segments 31 and 32, the work to
insert the coils 21, 22, and 23 into the slots 13 of the stator
core 10 is facilitated, as compared with the case where six
winding portions of each of the coils 21, 22, and 23 are
individually handled. 10 [0136]
FIGS. 18(A) to 18(C) are schematic diagrams illustrating a
method of forming the coil segment 31. As shown in FIG. 18(A),
an annular coil 200, which is a bundle of copper wires serving as
the coil segment 31, is stretched over three frame portions 501, 15 502, and 503 arranged at positions corresponding to three
vertices of an equilateral triangle.
[0137]
A pressing portion 504 is disposed so as to face the
annular coil 200 between the frames 501 and 502. Similarly, a 20 pressing portion 505 is disposed so as to face the annular coil
200 between the frames 502 and 503, and a pressing portion 506 is
disposed so as to face the annular coil 200 between the frames
503 and 501.
[0138] 25 Each of the pressing portions 504, 505, and 506 has an arcshaped
concave surface (referred to as a tip end surface) on the
annular coil 200 side. The pressing portions 504, 505, and 506
are configured to be movable toward a center position of the
triangle having three vertices at the frames 501, 502, and 503. 30 [0139]
As shown in FIG. 18(B), when the pressing portions 504, 505,
and 506 are moved toward the center of the triangle, the annular
coil 200 is pressed by the pressing portions 504, 505, and 506
37
and recessed to the inner circumferential side, so that the
annular coil 200 is formed into a star shape.
[0140]
That is, the annular coil 200 is formed into the star shape
that includes three outer peripheral portions held by the frame 5 portions 501, 502, and 503, three inner peripheral portions
pressed by the pressing portions 504, 505, and 506, and six
straight portions each located between these outer and inner
peripheral portions.
[0141] 10 Thereafter, the pressing portions 504, 505, and 506 are
separated from the annular coil 200, and the annular coil 200 is
detached from the frames 501, 502, and 503, so that a star-shaped
coil is obtained as illustrated in FIG. 18(C). The star-shaped
coil includes the three outer peripheral portions (i.e., coil 15 ends 213), the three inner peripheral portions (i.e., coil ends
215), and the six straight portions (i.e., the straight portions
211 and 212) between the outer and inner peripheral portions.
[0142]
The coil segment 31 shown in FIG. 16(A) is obtained by 20 bending the straight portions (i.e., the straight portions 211
and 212) of the star-shaped coil so that the inner peripheral
portions (i.e., the coil ends 215) are located at the bottom.
The coil segment 32 illustrated in FIG. 16(B) is formed in the
same manner. 25 [0143]
Next, a manufacturing method of the stator 1 of the second
embodiment will be described. The stator 1 of the second
embodiment is the same as the stator 1 of the first embodiment
except for the coil 2, and thus the figures of the first 30 embodiment are referred as needed.
[0144]
FIG. 17 is a flowchart illustrating an assembly process of
the stator 1 of the second embodiment. First, a plurality of
38
electromagnetic steel sheets are stacked in the axial direction
and integrally fixed together by crimping or the like to thereby
obtain the stator core 10, as described in the first embodiment
(step S121).
[0145] 5 Then, the coil segment 31 including the U-phase winding
portions 21A, 21C, and 21E (the first winding portions) are
inserted into the slots 13 of the stator core 10 (step S122).
The coil ends 213 of the U-phase winding portions 21A, 21C, and
21E are deformed outward in the radial direction. 10 [0146]
Then, the coil segment 32 including the U-phase winding
portions 21B, 21D, and 21F (the second winding portions) are
inserted into the slots 13 of the stator core 10 (step S123).
The coil ends 213 of the U-phase winding portions 21B, 21D, and 15 21F are deformed outward in the radial direction. Subsequently,
the insulating film 41 (FIG. 1) is disposed on the inner side of
the U-phase winding portions 21A to 21F in the radial direction.
[0147]
Then, the coil segment 31 including the V-phase winding 20 portions 22A, 22C, and 22E (the first winding portions) are
inserted into the slots 13 of the stator core 10 (step S124).
The coil ends 223 (see FIG. 11(C)) of the V-phase winding
portions 22A, 22C, and 22E are deformed outward in the radial
direction. 25 [0148]
Then, the coil segment 32 including the V-phase winding
portions 22B, 22D, and 22F (the first winding portions) are
inserted into the slots 13 of the stator core 10 (step S125).
The coil ends 223 (see FIG. 11(D)) of the V-phase winding 30 portions 22B, 22D, and 22F are deformed outward in the radial
direction. Subsequently, the insulating film 42 (FIG. 5) is
disposed on the inner side of the V-phase winding portions 22A to
22F in the radial direction.
39
[0149]
Then, the coil segment 31 including the W-phase winding
portions 23A, 23C, and 23E (the first winding portions) are
inserted into the slots 13 of the stator core 10 (step S126).
The coil ends 234 (see FIG. 11(E)) of the W-phase winding 5 portions 23A, 23C, and 23E are deformed outward in the radial
direction.
[0150]
Then, the coil segment 32 including the W-phase winding
portions 23B, 23D, and 23F (second winding portions) are inserted 10 into the slots 13 of the stator core 10 (step S127). The coil
ends 234 (see FIG. 11(F)) of the W-phase winding portions 23B,
23D, and 23F are deformed outward in the radial direction. As
above, the insertion of the U-phase coil 21, the V-phase coil 22,
and the W-phase coil 23 into the slots 13 of the stator core 10 15 is completed.
[0151]
Subsequently, as described in the first embodiment, the
coil ends 213, 223, and 233 of the coils 21, 22, and 23 are
shaped (step S128). Then, the U-phase coil 21, the V-phase coil 20 22, and the W-phase coil 23 are electrically connected (step
S129). Consequently, the assembling of the stator 1 is completed.
[0152]
The motor of the second embodiment is configured in a
similar manner to the motor 100 of the first embodiment except 25 for the configuration of the coils 21, 22, and 23.
[0153]
As described above, in the second embodiment, the U-phase
coil 21 includes the coil segment 31 in which the U-phase winding
portions 21A, 21C, and 21E, the number of which is half the 30 number of magnetic poles, are connected in the wave shape, and
the coil segment 32 in which the U-phase winding portions 21B,
21D, and 21F are connected in the wave shape. The V-phase coil
22 and the W-phase coil 23 are configured in the same manner as
40
the U-phase coil 21. Thus, the work to insert the U-phase coil
21, the V-phase coil 22, and the W-phase coil 23 into the slots
13 can be facilitated, and the time required for the work can be
reduced.
[0154] 5 In FIGS. 16(A) to 16(C) and FIG. 17, the average
circumference length of each of the U-phase winding portions 21A,
21C, and 21E (the coil segment 31) and the average circumference
length of each of the U-phase winding portions 21B, 21D, and 21F
(the coil segment 31) are the same, but as described in the first 10 embodiment, the average circumference length of each of the Uphase
winding portions 21A, 21C, and 21E may be longer than the
average circumference length of each of the U-phase winding
portions 21B, 21D, and 21F.
[0155] 15 Third Embodiment
Next, a third embodiment will be described. FIG. 20 is a
cross-sectional view illustrating a motor 101 of the third
embodiment. The motor 101 of the third embodiment is an
induction motor and differs from the motor of the first 20 embodiment in the configuration of a rotor 6. A stator 1 of the
motor 101 of the third embodiment is the same as the stator 1 of
the first embodiment.
[0156]
The rotor 6 includes a rotor core 60 having a plurality of 25 slots 61, a shaft 66 which is a rotation shaft, and rotor bars 62
inserted into the slots 61 of the rotor core 60.
[0157]
The rotor core 60 is composed of electromagnetic steel
sheets, each having a thickness of, for example, 0.1 mm to 0.7 mm, 30 which are stacked in the axial direction and integrally fixed
together by crimping or the like. The rotor core 60 has a shaft
hole 63 formed at its center in the radial direction. The shaft
66 is fixed to the shaft hole 63. An axis C1 which is a central
41
axis of the shaft 66 serves as the rotation axis of the rotor 6.
[0158]
The rotor core 60 is formed annularly about the axis C1.
The plurality of slots 61 (also referred to as rotor slots) are
formed at equal intervals in the circumferential direction along 5 the outer circumference of the rotor core 60. The number of
slots 61 is 24 in this example, but is not limited thereto. The
slots 61 pass through the rotor core 60 in the axial direction.
[0159]
FIG. 21 is a perspective view illustrating the rotor 6. 10 The rotor 6 has a pair of end rings 65, i.e., one end ring 65 on
each of both ends of the rotor core 60 in the axial direction.
The end rings 65 are connected to both ends of each rotor bar 62
in the axial direction, and are formed integrally with the rotor
bars 62. The rotor bars 62 and the end rings 65 constitute a 15 squirrel cage secondary conductor.
[0160]
The rotor bars 62 and the end rings 65, which constitute
the squirrel cage secondary conductor, are made of a non-magnetic
conductive material such as, for example, aluminum. The rotor 20 bars 62 and the end rings 65 are formed by casting aluminum at
both ends of the rotor core 60 and into the slots 61. Copper may
be used instead of aluminum. In FIG. 21, only a single rotor bar
62 is illustrated using a dashed line.
[0161] 25 When the magnetic flux of the stator 1 interlinks with the
rotor bar 62 of the rotor 6, a secondary current is generated in
the rotor bar 62. This secondary current and the magnetic flux
of the stator 1 generate a torque that rotates the rotor 6.
[0162] 30 The stator 1 has the configuration described in the first
embodiment and the coil ends are small, and thus the
manufacturing cost of the motor 101 can be reduced. Since the
coil ends are small, the electrical resistance is reduced and the
42
loss is reduced, so that the motor efficiency can be improved.
Furthermore, the reduction in the weight and size of the motor
101 can be achieved.
[0163]
The coils 21, 22, and 23 (coil segments 31 and 32) 5 described in the second embodiment may be applied to the motor
101 of the third embodiment.
[0164]
As described above, in the third embodiment, the stator 1
of the first or second embodiment is used in the motor 101 which 10 is an induction motor. Thus, the manufacturing cost of the motor
101 can be reduced, the motor efficiency can be improved, and the
weight and size of the motor 101 can be reduced.
[0165]
In the above-described first to third embodiments, the U- 15 phase coil 21 is located outermost in the radial direction while
the W-phase coil 23 is located innermost in the radial direction
(see FIG. 4), but the arrangement of coils is not limited to such
an example.
[0166] 20 Further, in the above-described first to third embodiments,
three-phase coils composed of the U-phase coil 21, the V-phase
coil 22, and the W-phase coil 23 have been described, but the
coils are not limited to the three-phase coils, but may be twophase
coils, for example. 25 [0167]
(Compressor)
Next, the compressor 300 to which the motor described in
each embodiment is applicable will be described. FIG. 22 is a
cross-sectional view illustrating the compressor 300. The 30 compressor 300 is a scroll compressor and includes a closed
container 307, a compression mechanism 305 disposed in the closed
container 307, the motor 100 that drives the compression
mechanism 305, the shaft 56 connecting the compression mechanism
43
305 with the motor 100, and a subframe 308 that supports a lower
end of the shaft 56 (i.e., an end of the shaft opposite to the
compression mechanism 305).
[0168]
The compression mechanism 305 includes a fixed scroll 301 5 having a spiral portion, a swing scroll 302 having a spiral
portion forming a compression chamber between this spiral portion
and the spiral portion of the fixed scroll 301, a compliance
frame 303 that holds an upper end of the shaft 56, and a guide
frame 304 that is fixed to the closed container 307 and holds the 10 compliance frame 303.
[0169]
A suction pipe 310 that penetrates the closed container 307
is press-fitted into the fixed scroll 301. The closed container
307 is provided with a discharge pipe 311 that allows high- 15 pressure refrigerant gas discharged from the fixed scroll 301 to
be discharged to the outside. The discharge pipe 311
communicates with a not shown opening provided between the
compression mechanism 305 and the motor 100 in the closed
container 307. 20 [0170]
The motor 100 is fixed to the closed container 307 by
fitting the stator 1 into the closed container 307. The
configuration of the motor 100 is as described above. A glass
terminal 309 for supplying electric power to the motor 100 is 25 fixed to the closed container 307 by welding.
[0171]
When the motor 100 rotates, the rotation of the motor 100
is transmitted to the swing scroll 302, and the swing scroll 302
swings. When the swing scroll 302 swings, a volume of the 30 compression chamber formed between the spiral portion of the
swing scroll 302 and the spiral portion of the fixed scroll 301
changes. Refrigerant gas is sucked therein through the suction
pipe 310, compressed, and discharged through the discharge pipe
44
311.
[0172]
The compressor 300 has the motor 100 described in the first
embodiment. Thus, the manufacturing cost of the compressor 300
can be reduced, and the operating efficiency of the compressor 5 300 can be improved.
[0173]
The slots 13 of the stator 1 in the motor 100 are densely
filled with the coils 21, 22, and 23, and the flow paths for
refrigerant and refrigerating machine oil have little unevenness. 10 This makes the flow of refrigerant and refrigerating machine oil
smooth, and further improves the operating efficiency of the
compressor 300.
[0174]
In the compressor 300, it is also possible to use the motor 15 101 described in the third embodiment instead of the motor 100.
The coils 21, 22, and 23 (coil segments 31 and 32) described in
the second embodiment may be applied.
[0175]
The scroll compressor has been described as an example of 20 the compressor, but the motor described in the embodiments may be
applied to any compressor other than the scroll compressor.
[0176]
(Air Conditioner)
Next, an air conditioner 400 to which the motor described 25 in each of the above-described embodiments is applicable will be
described. FIG. 23 is a diagram illustrating the air conditioner
400 (a refrigeration cycle apparatus). The air conditioner 400
includes a compressor 401, a condenser 402, a throttle device (a
decompression device) 403, and an evaporator 404. The compressor 30 401, the condenser 402, the throttle device 403, and the
evaporator 404 are coupled together by a refrigerant pipe 407 to
constitute a refrigeration cycle. That is, refrigerant
circulates through the compressor 401, the condenser 402, the
45
throttle device 403, and the evaporator 404 in this order.
[0177]
The compressor 401, the condenser 402, and the throttle
device 403 are provided in an outdoor unit 410. The compressor
401 is constituted by the compressor 300 illustrated in FIG. 22. 5 The outdoor unit 410 is provided with an outdoor fan 405 that
supplies outdoor air to the condenser 402. The evaporator 404 is
provided in an indoor unit 420. The indoor unit 420 is provided
with an indoor fan 406 that supplies indoor air to the evaporator
404. 10 [0178]
The operation of the air conditioner 400 is as follows.
The compressor 401 compresses sucked refrigerant, and sends out
the compressed refrigerant. The condenser 402 exchanges heat
between the refrigerant flowing in from the compressor 401 and 15 the outdoor air to condense and liquefy the refrigerant, and
sends out the liquefied refrigerant to the refrigerant pipe 407.
The outdoor fan 405 supplies outdoor air to the condenser 402.
The pressure or the like of the refrigerant flowing through the
refrigerant pipe 407 is adjusted by changing the opening degree 20 of the throttle device 403.
[0179]
The evaporator 404 exchanges heat between the refrigerant
brought into a low-pressure state by the throttle device 403 and
the indoor air to cause the refrigerant to take heat from the 25 indoor air and evaporate (vaporize), and then sends out the
evaporated refrigerant to the refrigerant pipe 407. The indoor
fan 406 supplies the indoor air to the evaporator 404. Thus,
cooled air from which heat is removed in the evaporator 404 is
supplied into the room. 30 [0180]
By using the motor 100 described in the first or second
embodiment or the motor 101 described in the third embodiment in
the compressor 401 (i.e., the compressor 300), the manufacturing
46
cost of the air conditioner 400 can be reduced, and the operating
efficiency of the air conditioner 400 can be improved.
[0181]
Although the desirable embodiments of the present invention
have been specifically described, the present invention is not 5 limited to the above-described embodiments, and various
modifications and changes can be made to those embodiments
without departing from the scope of the present invention.
DESCRIPTION OF REFERENCE CHARACTERS
[0182] 10 1, 1A, 1B, 1C stator; 2 coil; 5, 5A, 6 rotor; 10, 10A,
10B, 1C stator core; 11 yoke; 12 tooth; 13 slot; 15, 16 end
surface; 21 U-phase coil; 21A, 21C, 21E U-phase winding portion
(first winding portion); 21B, 21D, 21F U-phase winding portion
(second winding portion); 211, 212 straight portion (slot 15 insertion portion); 213, 214 coil end; 22A, 22C, 22E V-phase
winding portion (first winding portion); 22B, 22D, 22F V-phase
winding portion (second winding portion); 221, 222 straight
portion (slot insertion portion); 223, 224 coil end; 23A, 23C,
23E W-phase winding portion (first winding portion); 23B, 23D, 20 23F W-phase winding portion (second winding portion); 231, 232
straight portion (slot insertion portion); 233, 234 coil end;
31 coil segment (first coil segment); 32 coil segment (second
coil segment); 41, 42 insulating film; 50 rotor core; 51, 51A
magnet insertion hole; 52 flux barrier ; 53 shaft hole; 55 25 permanent magnet; 56 shaft; 60 rotor core; 61 slot; 62 bar;
63 shaft hole; 65 end ring; 66 shaft; 100, 101 motor; 200
wire; 211, 212 straight portion (slot insertion portion); 213,
214 coil end; 215 coil end; 221, 222 straight portion; 223, 224
coil end; 231, 232 straight portion; 233, 234 coil end; 300 30 compressor; 305 compression mechanism; 307 closed container;
400 air conditioner; 401 compressor; 402 condenser; 403
throttle device; 404 evaporator; 407 refrigerant pipe; 410
outdoor unit; 420 indoor unit.
35
47
We Claim:
1. A stator comprising:
a stator core having a plurality of slots in a
circumferential direction about an axis, the stator core having 5 an end surface in a direction of the axis; and
a first coil and a second coil each wound on the stator
core in distributed winding, the first coil and the second coil
being of different phases,
wherein a winding factor is 1; 10 wherein each of the first coil and the second coil has
winding portions, the number of which corresponds to the number
of poles;
wherein the winding portions, the number of which
corresponds to the number of poles, include a first winding 15 portion and a second winding portion that are adjacent to each
other in the circumferential direction;
wherein the first winding portion and the second winding
portion are inserted into one slot of the plurality of slots and
extend from the one slot to both sides in the circumferential 20 direction on the end surface; and
wherein the first coil and the second coil are annularly
disposed in different positions in a radial direction about the
axis on the end surface of the stator core.
25 2. The stator according to claim 1, wherein the first winding
portion is disposed on an outer side in the radial direction with
respect to the second winding portion.
3. The stator according to claim 2, wherein an average 30 circumference length of the second winding portion is longer than
an average circumference length of the first winding portion.
4. The stator according to any one of claims 1 to 3, wherein a
48
space factor of the first winding portion in the slot is smaller
than a space factor of the second winding portion in the slot.
5. The stator according to any one of claims 1 to 4, wherein
the winding portions, the number of which corresponds to the 5 number of poles, include a first segment and a second segment,
each of the first segment and the second segment being obtained
by connecting the winding portions, the number of which is half
the number of poles, in a wave shape, and
wherein the first segment includes the first winding 10 portion, and the second segment includes the second winding
portion.
6. The stator according to claim 5, wherein the first segment
is disposed on an outer side in the radial direction with respect 15 to the second segment.
7. The stator according to any one of claims 1 to 6, wherein
an insulating film is disposed between the first coil and the
second coil on the end surface of the stator core. 20
8. The stator according to claim 7, wherein the insulating
film is disposed annularly about the axis.
9. The stator according to any one of claims 1 to 8, wherein a 25 value obtained by dividing the number of slots in the stator core
by a product of the number of poles and the number of phases is 1.
10. The stator according to any one of claims 1 to 9, further
comprising a third coil of a different phase from each of the 30 first coil and the second coil.
11. A motor comprising:
the stator according to any one of claims 1 to 10; and
49
a rotor rotatably provided inside the stator.
12. The motor according to claim 11, wherein the motor is a
synchronous motor.
5 13. The motor according to claim 11, wherein the motor is an
induction motor.
14. A compressor comprising:
the motor according to any one of claims 11 to 13; and 10 a compression mechanism driven by the motor.
15. An air conditioner comprising a compressor, a condenser, a
decompression device, and an evaporator,
the compressor comprising a motor, and a compression 15 mechanism driven by the motor,
the motor comprising:
the stator according to any one of claims 1 to 10; and
a rotor rotatably provided inside the stator.
20 16. A manufacturing method of a stator, the method comprising
the steps of:
preparing a stator core that has a plurality of slots in a
circumferential direction about an axis, the stator core having
an end surface in a direction of the axis; 25 attaching a first coil to the stator core so that a first
winding portion and a second winding portion of the first coil
are inserted into one slot of the plurality of slots and extend
from the one slot to both sides in the circumferential direction
on the end surface; and 30 attaching a second coil of a different phase from the first
coil, to the stator core so that a first winding portion and a
second winding portion of the second coil are inserted into
another slot, which is different from the one slot, of the
50
plurality of slots and extend from the another slot to both sides
in the circumferential direction on the end surface,
wherein the step of attaching the second coil to the stator
core comprises attaching the second coil on an inner side in a
radial direction about the axis with respect to the first coil. 5
17. The method for manufacturing a stator according to claim 16,
wherein the step of attaching the first coil to the stator core
comprises:
attaching the first winding portion of the first coil to 10 the stator core; and
attaching the second winding portion of the first coil to
an inner side of the first winding portion of the first coil in
the radial direction on the stator core, and
wherein the step of attaching the second coil to the stator 15 core comprises:
attaching the first winding portion of the second coil to
the stator core; and
attaching the second winding portion of the second coil to
an inner side of the first winding portion of the second coil in 20 the radial direction on the stator core.
18. The method for manufacturing a stator according to claim 16,
wherein the step of attaching the first coil to the stator core
comprises: 25 attaching a first segment to the stator core, the first
segment being obtained by connecting a plurality of the first
winding portions of the first coil in a wave shape; and
attaching a second segment to an inner side of the first
segment of the first coil in the radial direction on the stator 30 core, the second segment being obtained by connecting a plurality
of the second winding portions of the first coil in a wave shape,
and
wherein the step of attaching the second coil to the stator
51
core comprises:
attaching a first segment to the stator core, the first
segment being obtained by connecting a plurality of the first
winding portions of the second coil in a wave shape; and
attaching a second segment to an inner side of the first 5 segment of the second coil in the radial direction on the stator
core, the second segment being obtained by connecting a plurality
of the second winding portions of the second coil in a wave shape.