1
FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
STATOR, ROTARY ELECTRIC MACHINE, AND COMPRESSOR;
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]
5 The present disclosure relates to a stator, a rotary electric machine including
the stator, and a compressor including the rotary electric machine, and in particular to
a structure of a laminated core.
Background Art
[0002]
10 As a stator used for an existing rotary electric machine, a stator including a
closed slot structure is known (for example, see Patent Literature 1). The stator
includes a plurality of split cores each made of a plurality of laminated core materials,
and each including a short-sided yoke portion and a tooth portion protruding toward
an inside of the yoke portion. After a coil is wound around the tooth portion of each
15 of the plurality of split cores, the plurality of split cores are annularly arranged, and the
adjacent yoke portions and the adjacent tooth portions are abutted, or joined and
fixed by welding, bonding, or the like, to configure the closed slot structure.
[0003]
The stator disclosed in Patent Literature 1 includes an annular stator core and
20 the coils. The annular stator core includes the plurality of split cores radially divided
with a center thereof as a reference. Each of the coils is wound around each of the
plurality of split cores with an insulation material in between. The plurality of split
cores around which the coils are wound are annularly arranged while the adjacent
yoke portions and the adjacent tooth tip portions are abutted, joined, and fixed. As a
25 result, the stator has the closed slot structure. Thereafter, joining portions of the
yoke portions and joining portions of the tooth tip portions are welded by laser welding
(for example, YAG laser welding) or bonded with an adhesive.
[0004]
As described above, the closed slot structure of the stator is configured in such
30 a manner that the coils are wound around the tooth portions of the plurality of split

3
cores with the insulation materials in between, and then the plurality of split cores are
annularly arranged while the adjacent yoke portions and the adjacent tooth tip
portions are joined and fixed. Therefore, the coils are rapidly and easily wound
around the tooth portions of the split cores with high density. Further, the closed slot
5 structure is configured by joining and fixing not only the yoke portions of the split
cores but also the tooth portions positioned on the inner peripheral side. Therefore,
even in a case where an electromagnetic force is applied to the split cores,
deformation of the stator can be prevented. This makes it possible to realize a rotary
electric machine with low noise and low vibration.
10 Citation List
Patent Literature
[0005]
Patent Literature 1: Japanese Unexamined Patent Application Publication No.
2004-180383
15 Summary of Invention
Technical Problem
[0006]
According to the structure of the existing stator disclosed in Patent Literature 1,
the joining portions of the yoke portions and the joining portions of the tooth tip
20 portions are welded by laser welding or bonded with an adhesive. Therefore, in a
case where regulation of inner/outer diameters of the split cores is insufficient at
welding or bonding, the split cores are shifted from each other, which deteriorates a
roundness of the inner/outer diameters of the stator.
[0007]
25 Further, variation in shapes of the split cores causes variation in gaps of the
adjacent yoke portions and in gaps of the adjacent tooth tip portions.
[0008]
The present disclosure is made to solve the above-described issues, and an
object of the present disclosure is to provide a stator, a rotary electric machine, and a
30 compressor that are high in joining accuracy on an inner diameter side and an outer

4
diameter side of split cores and include high-density coils rapidly and easily formed.
Solution to Problem
[0009]
A stator according to one embodiment of the present disclosure is a stator
5 obtained by winding a coil around a stator core having an annular shape, with an
insulation material in between. The stator core includes a plurality of split cores.
The plurality of split cores include first split cores and second split cores coupled
adjacently to each other, and are a coupled laminated core in which the split cores
are annularly coupled and arranged. Each of the plurality of split cores at least
10 partially includes a plurality of first parts and a plurality of second parts alternately
laminated at least at a part. The plurality of first parts and the plurality of second
parts each have a plate shape. Each of the plurality of first parts and the plurality of
second parts includes a yoke portion, a tooth portion, and a tooth tip portion. The
yoke portion includes a coupling portion at one end and a yoke end portion at another
15 end. The tooth portion is integrated with the yoke portion and protrudes from a
center of the yoke portion toward an inner peripheral side of the stator core. The
tooth tip portion is integrally provided at a front end on an inner peripheral side of the
tooth portion. The coupling portion of the yoke portion of each of the plurality of first
parts is positioned at an end on a side opposite to the coupling portion of the yoke
20 portion of each of the plurality of second parts. The coupling portion of each of the
plurality of first parts of each of the first split cores is sandwiched between the
coupling portions of the plurality of second parts of adjacent one of the second split
cores, and abuts on the yoke end portion of the corresponding first part of adjacent
one of the second split cores. Each of the first split cores and adjacent one of the
25 second split cores are coupled to be relatively rotatable around the coupling portion
therebetween. The tooth tip portion of each of the first split cores is at least partially
in contact with or fitted into the tooth tip portions of adjacent second split cores at both
ends in a circumferential direction.
[0010]
30 A rotary electric machine according to another embodiment of the present

5
disclosure includes the above-described stator.
[0011]
A compressor according to still another embodiment of the present disclosure
includes the above-described rotary electric machine, and a compression mechanism
5 driven by the rotary electric machine and configured to compress refrigerant.
Advantageous Effects of Invention
[0012]
According to the embodiments of the present disclosure, the stator core
includes what is called a joint structure in which the first split cores and the second
10 split cores are rotatably coupled at the respective coupling portions. Therefore, the
stator core is shaped in an annular shape after the coils are wound around the tooth
portions. As a result, the coils are rapidly and easily wound with high density.
Further, in the stator core, positional accuracy of the split cores is improved by the
joint structure. In addition, variation in gaps of the adjacent tooth tip portions is
15 reduced because the tooth tip portions come into contact with each other or are fitted
into each other by relatively rotating the first split cores and the second split cores.
Accordingly, in the stator core, joining accuracy of the split cores is improved on the
inner diameter side and the outer diameter side.
Brief Description of Drawings
20 [0013]
[Fig. 1] Fig. 1 is an explanatory diagram of a cross-sectional structure of a
compressor 1 according to Embodiment 1.
[Fig. 2] Fig. 2 is a plan view illustrating an annular arrangement of a stator core
80 of a stator 51 in an electric motor unit 50 according to Embodiment 1.
25 [Fig. 3] Fig. 3 is a plan view of a first part 11 out of core pieces 3 configuring
split cores 5 of the stator core 80.
[Fig. 4] Fig. 4 is a plan view of a second part 12 out of the core pieces 3
configuring the split cores 5 of the stator core 80.
[Fig. 5] Fig. 5 is an enlarged view of a coupling portion 5b illustrated in Fig. 2.
30 [Fig. 6] Fig. 6 is an enlarged cross-sectional view of the coupling portion 5b of

6
the stator core 80 according to Embodiment 1.
[Fig. 7] Fig. 7 is an enlarged view of a vicinity of end portions 5e of tooth tip
portions 5c in Fig. 2.
[Fig. 8] Fig. 8 is a plan view in a state where the stator core 80 and a housing 4
5 of the stator 51 are fixed.
[Fig. 9] Fig. 9 is an explanatory diagram of positional relationship between the
coupling portion 5b and end surfaces 5g of the tooth tip portions 5c of any adjacent
two of the split cores 5 of the stator core 80 according to Embodiment 1.
[Fig. 10] Fig. 10 is an annular arrangement diagram of a stator core 280
10 according to Embodiment 2.
[Fig. 11] Fig. 11 is an enlarged view of a vicinity of end surfaces 205g of tooth
tip portions 205c in the stator core 80 in Fig. 10.
Description of Embodiments
[0014]
15 A stator, a rotary electric machine, and a compressor according to Embodiment
1 are described below with reference to drawings and the like. In the following
drawings including Fig. 1, relative dimensional relationship, shapes, and the like of
components may be different from those of actual ones. Further, in the following
drawings, the same or equivalent components are denoted by the same reference
20 numerals, and this applies throughout the description. Further, terms indicating
directions (for example, "upper", "lower", "right", "left", "front", and "rear") are
appropriately used to facilitate understanding; however, these terms are used only for
description, and do not limit arrangement and directions of a device or a component.
In the specification, positional relationship of components, extending directions of the
25 components, arrangement directions of the components indicate those when the
device is installed in a usable state, in principle.
[0015]
Embodiment 1.
Fig. 1 is an explanatory diagram of a cross-sectional structure of a compressor
30 1 according to Embodiment 1. The compressor 1 illustrated in Fig. 1 is used to

7
compress refrigerant in, for example, a refrigeration cycle device. The compressor 1
includes a compression mechanism unit 30, an electric motor unit 50, and a sealing
container 60. The compression mechanism unit 30 compresses a fluid suctioned
from outside through a suction muffler 40 and a suction pipe 41. The fluid is gas
5 refrigerant in Embodiment 1. The electric motor unit 50 drives the compression
mechanism unit 30. The sealing container 60 houses the compression mechanism
unit 30 and the electric motor unit 50. The sealing container 60 is a pressure
container. High-pressure gas refrigerant compressed by the compression
mechanism unit 30 is discharged from the compression mechanism unit 30 to an
10 inside of the sealing container 60, and high-temperature high-pressure gas refrigerant
is discharged from a discharge pipe 42 to a refrigerant circuit. Further, refrigerating
machine oil (not illustrated) is stored in an inner bottom portion of the sealing
container 60.
[0016]
15 The sealing container 60 according to Embodiment 1 includes a body portion
61 having a cylindrical shape and a bottom portion, and an upper lid portion 62
closing an opening port in an upper part of the body portion 61. The body portion 61
and the upper lid portion 62 are airtightly joined by circumferential welding. The
structure of the sealing container 60 illustrated in Fig. 1 is illustrative, is not limited
20 thereto.
[0017]
The electric motor unit 50 is positioned slightly above a center of the sealing
container 60, and includes a stator 51 and a rotor 52 disposed on an inner peripheral
side of the stator 51. An outer peripheral surface of the stator 51 and an inner
25 peripheral surface of the body portion 61 are fixed by, for example, welding. The
stator 51 is formed in an annular shape. The rotor 52 is rotatably disposed with a
slight gap from an inner peripheral surface of the stator 51.
[0018]
A main shaft 53 is fitted into the rotor 52, and the rotor 52 rotates integrally with
30 the main shaft 53. The main shaft 53 includes an eccentric portion 54 at one end,

8
thereby serving as a crankshaft. The eccentric portion 54 is eccentric from a center
axis L of the main shaft 53, and has a center axis C shifted from the center axis L.
The eccentric portion 54 eccentrically rotates around the center axis L by rotation of
the rotor 52.
5 [0019]
The compression mechanism unit 30 includes a cylinder 20, a main bearing 31
and a sub-bearing 32, and a rolling piston 22. The main bearing 31 and the subbearing 32 are disposed to respectively face upper and lower end surfaces of the
cylinder 20 and also serve as end plates of the cylinder 20. The rolling piston 22 is
10 housed inside the cylinder 20. The eccentric portion 54 is fitted into the rolling piston
22. Further, a vane (not illustrated) dividing an internal space of the cylinder 20 into
a suction chamber and a compression chamber is inserted into a vane groove (not
illustrated) of the cylinder 20. The cylinder 20, the main bearing 31, and the subbearing 32 are integrally combined, and the rolling piston 22, the cylinder 20, the
15 eccentric portion 54, and the vane are movably housed in an inside thereof. An
internal part including the rolling piston 22, the cylinder 20, the eccentric portion 54,
and the vane compresses the gas refrigerant suctioned from the suction pipe 41 and
discharges the compressed gas refrigerant to the inside of the sealing container 60
every time the main shaft 53 rotates.
20 [0020]
The compressor 1 further includes the suction muffler 40 provided adjacently to
an outside of the sealing container 60. The suction muffler 40 stores low-pressure
refrigerant flowing through the refrigerant circuit and separates the refrigerant into gas
and liquid. Further, the suction muffler 40 has a cross-sectional area greater than a
25 cross-sectional area of a refrigerant pipe, which reduces noise.
[0021]
The compressor 1 includes the suction pipe 41 suctioning the gas refrigerant in
the suction muffler 40 into the sealing container 60, and a suction hole (not illustrated)
guiding the gas refrigerant suctioned through the suction pipe 41 into the suction
30 chamber inside the cylinder 20 of the compression mechanism unit 30. The

9
compressor 1 includes a discharge hole (not illustrated) discharging the high-pressure
gas refrigerant compressed in the compression chamber of the compression
mechanism unit 30 into the space inside the sealing container 60. The compressor
1 includes the discharge pipe 42 discharging the high-pressure gas refrigerant inside
5 the sealing container 60 to the outside, at an upper end of the sealing container 60,
and sends the high-pressure gas refrigerant to the refrigerant circuit.
[0022]
The compression of the refrigerant by the compressor 1 is described. In the
compressor 1, the main shaft 53 integrated with the rotor 52 rotates by rotation of the
10 rotor 52, and the eccentric portion 54 rotates along with rotation of the main shaft 53.
When the eccentric portion 54 rotates, the rolling piston 22 rotates and slides inside
the cylinder 20. In other words, the rolling piston 22 eccentrically rotates along an
inner peripheral surface of the cylinder 20. As a result, the gas refrigerant is
suctioned from the suction pipe 41 to the suction chamber in the cylinder 20, and the
15 gas refrigerant is compressed in the compression chamber in the cylinder 20. The
high-pressure gas refrigerant compressed in the compression chamber is discharged
to the space inside the sealing container 60, and is discharged to the outside of the
sealing container 60 from the discharge pipe 42.
[0023]
20 The stator 51 includes coils 55 each obtained by winding a conductive wire
around each of magnetic pole teeth 5a of the stator core 80 with an insulation
material 57 in between. The stator 51 generates a magnetic field by a current
supplied from a wire 56, and continuously changes the magnetic field to rotate the
rotor 52. The rotor 52 rotates with a predetermined torque at a predetermined
25 rotation speed, and transmits driving force to the main shaft 53. In other words, the
stator 51 and the rotor 52 configure the electric motor unit 50 that is a rotary electric
machine converting electric energy into rotational driving force. The electric motor
unit 50 transmits the driving force to the compression mechanism unit 30 through the
main shaft 53 to compress the refrigerant.
30 [0024]

10
Fig. 2 is a plan view illustrating an annular arrangement of the stator core 80 of
the stator 51 in the electric motor unit 50 according to Embodiment 1. Fig. 2 is a
diagram to explain arrangement of split cores 5 of the stator core 80 configuring the
stator 51 according to Embodiment 1. The stator core 80 includes the plurality of
5 split cores 5. Both ends of a yoke portion 5d of each of the plurality of split core 5
are coupled to adjacent split cores 5. A tooth tip portion 5c is positioned at a front
end of the magnetic pole tooth 5a that protrudes toward an inner peripheral side from
the yoke portion 5d of each of the split cores 5, and protrudes toward sides of an
extending direction of the magnetic pole tooth 5a. Each of end portions 5h of the
10 tooth tip portion 5c is in contact with or is positioned with a small gap from opposing
end portion 5h of the tooth tip portion 5c of the adjacent split core 5.
[0025]
The plurality of split cores 5 configuring the stator core 80 include first split
cores 71 and second split cores 72. The first split cores 71 and the second split
15 cores 72 are coupled adjacently to each other. The first split cores 71 and the
second split cores 72 are adjacently arranged to perform arc motion around
respective corresponding engagement portions 3b. As described above, each of
coupling portions 5b of the first split cores 71 and the second split cores 72 has what
is called a joint structure. The plurality of split cores 5 are coupled laminated cores
20 that are each configured by laminating a plurality of plate-shaped core pieces 3 each
made of a magnetic material, and are coupled.
[0026]
Fig. 3 is a plan view of a first part 11 out of the core pieces 3 configuring the
split cores 5 of the stator core 80. Fig. 4 is a plan view of a second part 12 out of the
25 core pieces 3 configuring the split cores 5 of the stator core 80. Each of the plurality
of split cores 5 at least partially includes the plate-shaped first parts 11 and the plateshaped second parts 12 alternately laminated. In Embodiment 1, the first parts 11
and the second parts 12 have symmetrical shapes about a center c1 of a tooth
portion 3a forming the magnetic pole tooth 5a of each split core 5.
30 [0027]

11
Each of the first parts 11 and second parts 12 has a yoke portion 3d, the tooth
portion 3a, and a tooth tip portion 3c. The yoke portion 3d is positioned on an outer
peripheral side of the stator core 80 and forms the yoke portion 5d of each split core
5. The tooth portion 3a protrudes from a center of the yoke portion 3d toward the
5 inner peripheral side of the stator core 80. The tooth tip portion 3c is a front end of
the tooth portion 3a. The tooth tip portion 3c includes end portions 3h protruding in a
right-left direction relative to a direction in which the tooth portion 3a extends from the
yoke portion 3d, namely, in a circumferential direction of the stator core 80 in Fig. 2.
Each of the end portions 3h includes an end surface 3g at a front end.
10 [0028]
As illustrated in Fig. 3 and Fig. 4, the yoke portion 3d of each of the first parts
11 and the yoke portion 3d of each of the second parts 12 have shapes symmetrical
about the center c1. The yoke portion 3d includes a coupling portion 3f at one of
ends. The coupling portion 3f has an edge portion 3fb at a corner portion 3fa on the
15 outer peripheral side in a planar view, and the edge portion 3fb is rounded in an arc
shape. The corner portion 3fa includes the engagement portion 3b. The
engagement portion 3b is formed such that one of surfaces of each core piece 3 as a
plate-shaped magnetic material configuring the first part 11 or the second part 12 is
recessed and the other surface protrudes. For example, the engagement portion 3b
20 is formed by half-blanking a plate material.
[0029]
Fig. 5 is an enlarged view of one coupling portion 5b illustrated in Fig. 2. The
coupling portion 3f of each of the core pieces 3 configuring the coupling portion 5b is
disposed to abut on a yoke end portion 3e of adjacent one of the split cores 5. The
25 yoke end portion 3e includes an arc portion 3ea having an arc shape corresponding
to a shape of the corner portion 3fa of the coupling portion 3f. The arc portion 3ea is
recessed in a shape in which the edge portion 3fb at the corner portion 3fa of the
coupling portion 3f is offset. The arc portion 3ea and the corresponding edge portion
3fb do not interfere with each other when each of the first parts 11 and the
30 corresponding second part 12 relatively rotates around the center of the engagement

12
portion 3b. However, the arc portion 3ea and the corresponding edge portion 3fb
are not necessarily concentric around the center of the engagement portion 3b as
long as each of the first split core 71 and the corresponding second split core 72 can
relatively rotate and move. In Fig. 5, in at least one of the plurality of coupling
5 portions 5b of the plurality of split cores 5 in the stator core 80 illustrated in Fig. 2, the
coupling portion 3f and the corresponding yoke end portion 3e abutting on each other
has a gap 3k therebetween as illustrated in Fig. 5.
[0030]
Fig. 6 is an enlarged cross-sectional view of one coupling portion 5b of the
10 stator core 80 according to Embodiment 1. In each of the coupling portions 5b of the
first split cores 71 and the second split cores 72 configuring the stator core 80, the
first parts 11 and the second parts 12 are alternately overlapped, and the coupling
portion 3f of each of the first parts 11 of each of the first split cores 71 is sandwiched
between the coupling portions 3f of the second parts 12 of adjacent one of the second
15 split cores 72. The coupling portion 3f of each of the first parts 11 of each of the first
split cores 71 abuts on the yoke end portion 3e of adjacent one of the first parts 11 in
a direction parallel to the plate surfaces of the core pieces 3.
[0031]
As illustrated in Fig. 6, each of the engagement portions 3b has a recessed
20 portion 3ba recessed in a perpendicular direction on one of plate surfaces of the
corresponding core piece 3, and a projecting portion 3bb projecting in the
perpendicular direction. In each of the coupling portions 3f of the first split cores 71
and the second split cores 72, the projecting portion 3bb of one of the engagement
portions 3b is fitted into the recessed portion 3ba of the other engagement portion 3b,
25 thereby preventing each of the first parts 11 and the corresponding second part 12
from being detached in a direction parallel to the plate surfaces of the core pieces 3.
Each of the recessed portion 3ba and the corresponding projecting portion 3bb are
preferably fitted with a gap enabling each of the first split cores 71 and the
corresponding second split core 72 to relatively rotate and move. Each of the
30 engagement portions 3b is also referred to as a joint center because of serving as a

13
rotation center of the joint structure coupling each of the first split cores 71 and the
corresponding second split core 72. Further, a structure in which each of the first
split cores 71 and adjacent one of the second split cores 72 can relatively rotate and
move around the corresponding engagement portion 3b is referred to as the joint
5 structure in some cases.
[0032]
Fig. 7 is an enlarged view of a vicinity of end portions 5e of the tooth portions
5c in Fig. 2. Adjacent two of the end portions 5e of the tooth portions 5c of the stator
core 80 are coupled by abutting or fitting. In other words, the tooth tip portion 5c of
10 each of the first split cores 71 is at least partially in contact with or fitted into the tooth
tip portions 5c of adjacent second split cores at both ends in a circumferential
direction. In the stator core 80, the stator 51 having the closed slot structure is
formed by joining or bonding the tooth tip portions 5c.
[0033]
15 Fig. 8 is a plan view in a state where the stator core 80 and a housing 4 of the
stator 51 are fixed. In the stator core 80, after the plurality of split cores 5 are
linearly coupled, the magnetic pole teeth 5a of the respective split cores 5 are wound
with wires. Thereafter, the split cores 5 are annularly arranged as illustrated in Fig.
2. At this time, at least one of the plurality of coupling portions 5b of the plurality of
20 split cores 5 includes a gap as illustrated in Fig. 5. In contrast, no gap is provided
between any adjacent two of the end portions 5e of the tooth tip portions 5c of the
plurality of split cores 5. Such a configuration makes it possible to relax stress
applied from the housing 4 disposed outside the stator core 80 to the coupling
portions 5b of the yoke portions 5d of the stator core 80, and to suppress deformation
25 of the cores. Note that the housing 4 is, for example, a housing of the stator 51 or
the sealing container 60.
[0034]
At each of the end portions 3h of the tooth tip portions 3c of the core pieces 3
configuring the split cores 5, a thickness dimension in a radial direction in a state
30 where the plurality of split cores 5 are annularly arranged is set to twice or more a

14
material plate thickness, namely, a thickness dimension in a center axis direction, of
the core pieces 3. Therefore, the core pieces 3 are suppressed in influence of
punching distortion by pressing, and the end portions 3h of the tooth tip portions 3c
are arranged with appropriate positional relationship.
5 [0035]
Fig. 9 is an explanatory diagram of positional relationship between the coupling
portion 5b and end surfaces 5g of the tooth tip portions 5c of any adjacent two of the
split cores 5 of the stator core 80 according to Embodiment 1. The end surfaces 5g
of the tooth tip portions 5c of the stator core 80 are arranged on a concentric circle
10 around a center of the engagement portion 3b of the core pieces 3 forming the
coupling portion 5b. Therefore, in the stator core 80, after the magnetic pole teeth
5a are wound with wires, the end surfaces 5g of the tooth tip portions 5c of the
plurality of split cores 5 can be easily joined with high accuracy.
[0036]
15 Further, as for the end surfaces 5g of the tooth tip portions 5c of the stator core
80, a case where no gap is provided between any adjacent two of the end surfaces
3g of the core pieces 3 laminated in the center axis direction of the stator core 80 and
a case where a portion with no gap and a portion with a gap are mixed are
considered. In a case where the portion with no gap and the portion with a gap are
20 mixed, a magnetic flux is interrupted at the tooth tip portions 3c in the portion without
no gap. Further, rigidity of the stator core 80 is increased as the number of portions
with no gap is increased. Therefore, deformation of the stator core 80 caused by
force applied to the stator 51 is suppressed. This eventually reduces vibration of the
electric motor unit 50 caused by rotation.
25 [0037]
When the stator 51 according to Embodiment 1 is mounted on the compressor
1, a flow path resistance of the refrigerant near the end surfaces 5g of the tooth tip
portions 5c of the plurality of split cores 5 in the stator core 80 is reduced.
Therefore, stagnation of the refrigerating machine oil on the inner peripheral side of
30 the stator 51 is eliminated, and circulation of the refrigerating machine oil inside the

15
compressor 1 is improved. When the stagnation of the refrigerating machine oil on
the inner peripheral surface of the stator 51 is eliminated, a rotation load of the rotor
52 is reduced, which leads to improvement in efficiency of the electric motor unit 50.
Further, circulation of the refrigerating machine oil inside the sealing container 60 is
5 improved, which facilitates supply of the refrigerating machine oil to the compression
mechanism unit 30. As a result, deterioration of the compression mechanism unit 30
caused by abrasion or the like can be suppressed.
[0038]
Further, the stator 51 is annularly formed in a state where the coils 55 are
10 wound around the magnetic pole teeth 5a of the plurality of split cores 5 with the
insulation materials 57 in between and then the adjacent yoke portions 5d and the
adjacent tooth tip portions 5c of the plurality of split cores 5 are joined and fixed
through abutting or the like. As a result, the plurality of split cores 5 configure the
stator 51 having the closed slot structure. Therefore, the coils 55 can be rapidly and
15 easily wound around the magnetic pole teeth 5a of the respective split cores 5 with
high density.
[0039]
Embodiment 2.
In Embodiment 2, a coupling structure of the tooth tip portions 5c of the stator
20 core 80 of the stator 51 according to Embodiment 1 is changed. In Embodiment 2,
items not particularly described are similar to the items in Embodiment 1, and the
same functions and configurations as those in Embodiment 1 are described by using
the same reference numerals.
[0040]
25 Fig. 10 is an annular arrangement diagram of a stator core 280 according to
Embodiment 2. Fig. 11 is an enlarged view of a vicinity of end surfaces 205g of
tooth tip portions 205c of the stator core 80 in Fig. 10. The tooth tip portions 205c of
a plurality of split cores 205 of the stator core 80 according to Embodiment 2 are
coupled by combining recesses and projections provided at end surfaces 203g of the
30 tooth tip portions 203c of respective core pieces 203.

16
[0041]
An end surface 203ga of the tooth tip portion 203c of each of the core pieces
203 includes a protruding portion 203p. Further, an end surface 203gb of the tooth
tip portion 203c of each of the core pieces 203 includes a concave portion 203q into
5 which the opposing protruding portion 203p is fitted. The core pieces 203 forming
the split cores 5 of the stator core 280 each have the tooth tip portion 203c formed in
the same shape. In the stator core 280, the protruding portions and the concave
portions are combined and coupled as with the tooth tip portions 203c. This
improves fixing force of the adjacent tooth tip portions 205c of the split cores 205, and
10 improves rigidity. Accordingly, deformation of the stator core 280 caused by force
applied to the stator 51 is suppressed. This eventually further reduces vibration of
the electric motor unit 50 caused by rotation.
[0042]
Each of the plurality of split cores 205 may include only the core pieces 203, or
15 may mixedly include the core pieces 3 according to Embodiment 1 and the core
pieces 203. In a case of the split cores 205 each mixedly including the core pieces 3
and the core pieces 203, as for the tooth tip portions 205c of the split cores 205 of the
stator core 280, a portion with a partial gap and a portion with no gap in an axial
direction of the stator 51 are mixed. With such a configuration, in the compressor 1,
20 the gap between the tooth tip portions 205c of any adjacent two of the split cores 205
can be appropriately set. This makes it possible to improve rigidity of the stator 51
while meeting efficiency, noise, and vibration targeted by the compressor 1.
Reference Signs List
[0043]
25 1: compressor, 3: core piece, 3a: tooth portion, 3b: engagement portion, 3ba:
recessed portion, 3bb: projecting portion, 3c: tooth tip portion, 3d: yoke portion, 3e:
yoke end portion, 3ea: arc portion, 3f: coupling portion, 3fa: corner portion, 3fb: edge
portion, 3g: end surface, 3h: end portion, 4: housing, 5: split core, 5a: magnetic pole
tooth, 5b: coupling portion, 5c: tooth tip portion, 5d: yoke portion, 5f: yoke end portion,
30 5g: end surface, 5h: end portion, 11: first part, 12: second part, 20: cylinder, 22: rolling

17
piston, 30: compression mechanism unit, 31: main bearing, 32: sub-bearing, 40:
suction muffler, 41: suction pipe, 42: discharge pipe, 50: electric motor unit, 51: stator,
52: rotor, 53: main shaft, 54: eccentric portion, 55: coil, 56: wire, 57: insulation
material, 60: sealing container, 61: body portion, 62: upper lid portion, 71: first split
5 core, 72: second split core, 80: stator core, 203: core piece, 203c: tooth tip portion,
203g: end surface, 203ga: end surface, 203gb: end surface, 203p: protruding portion,
203q: concave portion, 205: split core, 205c: tooth tip portion, 205g: end surface, 280:
stator core, C: center axis, L: center axis, c1: center

We Claim:
[Claim 1]
5 A stator obtained by winding a coil around a stator core having an annular
shape, with an insulation material in between, wherein
the stator core includes a plurality of split cores,
the plurality of split cores include first split cores and second split cores coupled
adjacently to each other, and are a coupled laminated core in which the split cores
10 are annularly coupled and arranged,
each of the plurality of split cores at least partially includes a plurality of first
parts and a plurality of second parts alternately laminated at least at a part, the
plurality of first parts and the plurality of second parts each having a plate shape,
each of the plurality of first parts and the plurality of second parts includes a
15 yoke portion, a tooth portion, and a tooth tip portion, the yoke portion including a
coupling portion at one end and a yoke end portion at an other end, the tooth portion
being integrated with the yoke portion and protruding from a center of the yoke
portion toward an inner peripheral side of the stator core, the tooth tip portion being
integrally provided at a front end on an inner peripheral side of the tooth portion,
20 the coupling portion of the yoke portion of each of the plurality of first parts is
positioned at an end on a side opposite to the coupling portion of the yoke portion of
each of the plurality of second parts,
the coupling portion of each of the plurality of first parts of each of the first split
cores is sandwiched between the coupling portions of the plurality of second parts of
25 adjacent one of the second split cores, and abuts on the yoke end portion of the
corresponding first part of adjacent one of the second split cores,
each of the first split cores and adjacent one of the second split cores are
coupled to be relatively rotatable around the coupling portion therebetween, and
the tooth tip portion of each of the first split cores is at least partially in contact
30 with or fitted into the tooth tip portions of adjacent second split cores at both ends in a

19
circumferential direction.
[Claim 2]
The stator of claim 1, wherein the stator core includes a gap between each of
the plurality of first parts of each of the first split cores and the corresponding first part
5 of adjacent one of the second split cores.
[Claim 3]
The stator of claim 1 or 2, wherein, at each of end portions of the tooth tip
portions of the plurality of first parts and the plurality of second parts, a thickness
dimension in a radial direction of the stator core is twice or more a thickness
10 dimension in a center axis direction of the stator core.
[Claim 4]
The stator of any one of claims 1 to 3, wherein
each of the coupling portions of the plurality of first parts and the plurality of
second parts includes an engagement portion that includes a projecting portion on
15 one surface and a recessed portion on an other surface, and
each of the coupling portions of the plurality of first parts and the plurality of the
second parts is coupled by fitting the projecting portion of each of the plurality of first
parts into the recessed portion of the corresponding second part, and fitting the
projecting portion of each of the plurality of second parts into the recessed portion of
20 the corresponding first part.
[Claim 5]
The stator of claim 4, wherein an end portion of the tooth tip portion of each of
the first split cores and an opposing end portion of the tooth tip portion of adjacent
one of the second split cores are positioned on a concentric circle around a center of
25 the corresponding engagement portion.
[Claim 6]
A rotary electric machine comprising the stator of any one of claims 1 to 5.

[Claim 7]
A compressor, comprising:
the rotary electric machine of claim 6; and
a compression mechanism driven by the rotary electric machine and configured to
5 compress refrigerant.