FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
STATOR, ELECTRIC MOTOR, 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 100-8310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION
AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
2
DESCRIPTION
5 Technical Field
[0001]
The present disclosure relates to a stator including a distributed winding, to an
electric motor provided with the stator, and to a compressor provided with the electric
motor.
10 Background Art
[0002]
A compressor used for a refrigeration cycle device includes an electric motor
such as a synchronous electric motor. The electric motor includes a hollow
columnar stator wound with a winding, and a rotor disposed on an inner periphery of
15 the stator. A concentrated winding method is often used as a winding method for the
winding of the stator of the electric motor (see Patent Literature 1). This is because,
as compared with a distributed winding method, the concentrated winding method
enables reduction of coil ends and reduction of resistance of the winding. On the
other hand, when a size of the electric motor is increased to increase an output of the
20 electric motor with increase in capacity of the compressor, the distributed winding
method is more advantageous than the concentrated winding method in some cases.
This is because the distributed winding method is higher in winding factor than the
concentrated winding method, and can effectively use a magnetic flux of the rotor.
Therefore, the stator including the distributed winding is often used for the electric
25 motor of the compressor required to have a large capacity.
Citation List
Patent Literature
[0003]
Patent Literature 1: Japanese Unexamined Patent Application Publication No.
30 2008-061443
3
Summary of Invention
Technical Problem
[0004]
In recent years, the electric motor such as a synchronous electric motor and an
induction electric motor is required to have a small size and 5 high performance.
Therefore, to downsize the high-performance electric motor provided with the stator
including the distributed winding, for example, a method in which a wave winding is
used and one coil configuring one phase is disposed in one slot, to reduce a coil
circumferential length and a resistance value of the winding has been proposed.
10 The wave winding forms a coil by being wound around a stator core without a loop.
[0005]
However, there is an issue that the electric motor in which the wave winding is
used for the stator is lowered in reliability. More specifically, to form the wave
winding, a winding is wound in an annular shape to form an annular coil. Thereafter,
15 a plurality of portions on an outer periphery of the annular coil are pushed into an
inner peripheral side to form a star-shaped coil having a concave-convex shape.
Therefore, in the wave winding, an insulation coating of the winding may be damaged
or the like by external force applied to the winding in formation of the star-shaped coil,
to deteriorate insulation property, which may lower reliability.
20 [0006]
The present disclosure has been made to solve the above-described issues,
and a first object of the present disclosure is to provide a stator that can realize
downsizing and high performance of an electric motor and prevent reliability of the
electric motor from being lowered. In addition, a second object of the present
25 disclosure is to provide an electric motor and a compressor each provided with such a
stator.
Solution to Problem
[0007]
A stator according to one embodiment of the present disclosure includes: a
30 stator core having a hollow cylindrical shape and including a plurality of slots
4
arranged on an inner periphery at prescribed intervals in a circumferential direction;
and distributed concentric windings wound through the slots. The number of slots
per pole and phase is one. The winding of each phase includes the same number of
coils as the number of poles. Half of the coils are outer peripheral coils and are
arranged on an outer peripheral side of inner peripheral coils that 5 are remaining half
of the coils. The outer peripheral coils and the inner peripheral coils are alternately
arranged in the circumferential direction. When one of the outer peripheral coils and
one of the inner peripheral coils adjacent to each other are viewed, a part of the outer
peripheral coil and a part of the inner peripheral coil are housed in the same slot.
10 Coil ends of the coils configuring the winding of each phase are arranged in an
annular shape.
[0008]
An electric motor according to another embodiment of the present disclosure
includes: the stator according to the embodiment of the present disclosure; and a
15 rotor disposed on an inner periphery of the stator.
[0009]
A compressor according to still another embodiment of the present disclosure
includes: the electric motor according to another embodiment of the present
disclosure; and a compression mechanism configured to compress refrigerant by
20 driving force of the electric motor.
Advantageous Effects of Invention
[0010]
The stator according to the embodiment of the present disclosure includes the
distributed winding. When the coils of the winding of each phase are arranged as in
25 the stator according to the embodiment of the present disclosure, the coil ends can be
downsized, and the resistance value of the windings can be reduced. Therefore,
using the stator according to the embodiment of the present disclosure makes it
possible to realize downsizing and high performance of the electric motor. In
addition, the winding of the stator according to the embodiment of the present
30 disclosure is the concentric winding. In formation of the concentric winding, external
5
force applied in formation of the star-shaped coil of the wave winding is unnecessary.
Therefore, using the stator according to the embodiment of the present disclosure
makes it possible to prevent the reliability of the electric motor from being lowered.
Brief Description of Drawings
5 [0011]
[Fig. 1] Fig. 1 is a perspective view to explain a stator according to Embodiment
1 of the present disclosure and illustrating a stator core and a part of a winding.
[Fig. 2] Fig. 2 is a perspective view illustrating outer peripheral coils of a Uphase
winding of the stator according to Embodiment 1 of the present disclosure.
10 [Fig. 3] Fig. 3 is a perspective view illustrating inner peripheral coils of the Uphase
winding of the stator according to Embodiment 1 of the present disclosure.
[Fig. 4] Fig. 4 is a perspective view illustrating the outer peripheral coils and the
inner peripheral coils of the U-phase winding of the stator according to Embodiment 1
of the present disclosure.
15 [Fig. 5] Fig. 5 is a plan view to explain the stator according to Embodiment 1 of
the present disclosure and illustrating the stator core and the U-phase winding.
[Fig. 6] Fig. 6 is a plan view to explain the stator according to Embodiment 1 of
the present disclosure and illustrating the stator core, the U-phase winding, and a Vphase
winding.
20 [Fig. 7] Fig. 7 is a plan view to explain the stator according to Embodiment 1 of
the present disclosure and illustrating the stator core, the U-phase winding, the Vphase
winding, and a W-phase winding.
[Fig. 8] Fig. 8 is a perspective view to explain a process of inserting the Uphase
winding into slots of the stator core of the stator according to Embodiment 1 of
25 the present disclosure.
[Fig. 9] Fig. 9 is a perspective view to explain the process of inserting the Uphase
winding into the slots of the stator core of the stator according to Embodiment
1 of the present disclosure.
[Fig. 10] Fig. 10 is a perspective view to explain the process of inserting the U30
phase winding into the slots of the stator core of the stator according to Embodiment
6
1 of the present disclosure.
[Fig. 11] Fig. 11 is an explanatory diagram to explain a process of forming a
related-art wave winding.
[Fig. 12] Fig. 12 is an explanatory diagram to explain a process of forming a
related-art concentric 5 winding.
[Fig. 13] Fig. 13 is a plan view of the stator according to Embodiment 1 of the
present disclosure.
[Fig. 14] Fig. 14 is a plan view of a stator using the related-art concentric
winding.
10 [Fig. 15] Fig. 15 is a diagram illustrating an example of a wire connection
structure of a stator according to Embodiment 2 of the present disclosure.
[Fig. 16] Fig. 16 is a perspective view to explain an example of a stator
according to Embodiment 3 of the present disclosure and illustrating a stator core and
a part of a winding.
15 [Fig. 17] Fig. 17 is a perspective view to explain a process of winding a Uphase
winding of the stator according to Embodiment 3 of the present disclosure.
[Fig. 18] Fig. 18 is a perspective view to explain the process of winding the Uphase
winding of the stator according to Embodiment 3 of the present disclosure.
[Fig. 19] Fig. 19 is a perspective view to explain the process of winding the U20
phase winding of the stator according to Embodiment 3 of the present disclosure.
[Fig. 20] Fig. 20 is a perspective view to explain another example of the stator
according to Embodiment 3 of the present disclosure and illustrating the stator core
and the U-phase winding.
[Fig. 21] Fig. 21 is a perspective view to explain a process of winding the U25
phase winding of the stator illustrated in Fig. 20.
[Fig. 22] Fig. 22 is a perspective view to explain the process of winding the Uphase
winding of the stator illustrated in Fig. 20.
[Fig. 23] Fig. 23 is a diagram illustrating an example of a wire connection
structure of the stator illustrated in Fig. 20.
30 [Fig. 24] Fig. 24 is a cross-sectional view illustrating an example of an electric
7
motor according to Embodiment 4 of the present disclosure.
[Fig. 25] Fig. 25 is a vertical cross-sectional view illustrating an example of a
compressor according to Embodiment 5 of the present disclosure.
Description of Embodiments
5 [0012]
Embodiment 1
Fig. 1 is a perspective view to explain a stator according to Embodiment 1 of
the present disclosure and illustrating a stator core and a part of a winding.
A stator 20 according to Embodiment 1 includes a winding for each phase.
10 Therefore, in a case where an electric motor using the stator 20 is connected to a
three-phase alternating-current power supply, a winding of one of the three phases is
illustrated in Fig. 1. In Embodiment 1, description is made assuming that the electric
motor using the stator 20 is connected to the three-phase alternating-current power
supply. Further, in the following, the three phases are referred to as a U phase, a V
15 phase, and a W phase. As described below, in the stator 20 according to
Embodiment 1, a U-phase winding 7, a V-phase winding 8, and a W-phase winding 9
are arranged in order from an outer peripheral side to an inner peripheral side of the
stator 20. In other words, Fig. 1 illustrates the U-phase winding 7.
[0013]
20 The stator 20 includes a stator core 1 having a hollow cylindrical shape. The
stator core 1 includes a back yoke 1a having a hollow cylindrical shape in which a
through hole 1d is provided at a center. In the electric motor using the stator 20, a
rotor is disposed in the through hole 1d. The stator core 1 further includes a plurality
of teeth 1b protruding from an inner peripheral surface of the back yoke 1a. Each of
25 the teeth 1b extends along an axial direction of the through hole 1d. In other words,
each of the teeth 1b extends along an axial direction of the stator core 1. Further,
the teeth 1b are arranged at prescribed intervals in a circumferential direction of the
stator core 1. Therefore, a slot 1c is provided between the teeth 1b adjacent to each
other. In other words, the slots 1c are arranged on the inner periphery of the stator
30 core 1 at prescribed intervals in the circumferential direction of the stator core 1.
8
The stator core 1 is configured by stacking electromagnetic steel sheets punched in
an annular shape. Further, an inside of each of the slots 1c is insulated by a slot film
2.
[0014]
In the stator 20, the number of slots per pole and phase is 5 one. The winding
of each phase includes the same number of coils as the number of poles. More
specifically, the U-phase winding 7 includes the same number of coils as the number
of poles, the V-phase winding 8 also includes the same number of coils as the
number of poles, and the W-phase winding 9 also includes the same number of coils
10 as the number of poles. In Embodiment 1, the stator 20 that includes 18 slots 1c,
three phases, and six poles is illustrated. In this case, the U-phase winding 7
includes six coils. Further, the six coils are arranged every three slots. The six
coils of each of the V-phase winding 8 and the W-phase winding 9 are similarly
arranged. A pitch of the slots 1c is 360 degrees × 3/18 = 60 degrees mechanical
15 angle, and a winding factor is one.
[0015]
Fig. 2 is a perspective view illustrating outer peripheral coils of the U-phase
winding of the stator according to Embodiment 1 of the present disclosure. Fig. 3 is
a perspective view illustrating inner peripheral coils of the U-phase winding of the
20 stator according to Embodiment 1 of the present disclosure. Fig. 4 is a perspective
view illustrating the outer peripheral coils and the inner peripheral coils of the U-phase
winding of the stator according to Embodiment 1 of the present disclosure.
The detail of the U-phase winding 7 is described below with reference to Fig. 2
to Fig. 4 and Fig. 1 described above. Each of the V-phase winding 8 and the W25
phase winding 9 has a configuration similar to the configuration of the U-phase
winding 7. Therefore, description of the configuration of each of the V-phase
winding 8 and the W-phase winding 9 is omitted. In Fig. 1 to Fig. 4 and drawings
described below in Embodiment 1, illustration of jumper wires each connecting the
coils of the U-phase winding 7, lead wires of the U-phase winding 7, jumper wires
30 each connecting the coils of the V-phase winding 8, lead wires of the V-phase
9
winding 8, jumper wires each connecting the coils of the W-phase winding 9, and lead
wires of the W-phase winding 9 is omitted.
[0016]
The U-phase winding 7 is a distributed concentric winding wound through the
slots 1c. As described above, the U-phase winding 7 includes the six 5 coils. Half of
the six coils are the outer peripheral coils 3. Remaining half of the six coils are the
inner peripheral coils 4. The outer peripheral coils 3 are disposed on an outer
peripheral side of the inner peripheral coils 4. The outer peripheral coils 3 and the
inner peripheral coils 4 are alternately arranged in the circumferential direction of the
10 stator core 1.
[0017]
As described above, the six coils of the U-phase winding 7 are arranged every
three slots. In other words, the outer peripheral coils 3 and the inner peripheral coils
4 are alternately arranged every three slots. Accordingly, when one of the outer
15 peripheral coils 3 and one of the inner peripheral coils 4 adjacent to each other are
viewed, a part of the outer peripheral coil 3 and a part of the inner peripheral coil 4
are housed in the same slot 1c. In other words, when the outer peripheral coil 3, the
inner peripheral coil 4, and the slot 1c housing a part of the outer peripheral coil 3 and
a part of the inner peripheral coil 4 are viewed from the inner periphery of the stator
20 core 1, the outer peripheral coil 3 is disposed on a side opposite to the inner
peripheral coil 4 with the slot 1c as a reference.
[0018]
Fig. 5 is a plan view to explain the stator according to Embodiment 1 of the
present disclosure and illustrating the stator core and the U-phase winding. Fig. 6 is
25 a plan view to explain the stator according to Embodiment 1 of the present disclosure
and illustrating the stator core, the U-phase winding, and the V-phase winding. Fig.
7 is a plan view to explain the stator according to Embodiment 1 of the present
disclosure and illustrating the stator core, the U-phase winding, the V-phase winding,
and the W-phase winding.
30 [0019]
10
As illustrated in Fig. 5, the U-phase winding 7 provided in the stator core 1 is
shaped such that coil ends of the inner peripheral coils 4 and coil ends of the outer
peripheral coils 3 are overlapped in a planar view, and the coil ends of the coils
configuring the U-phase winding 7 are arranged in an annular shape. The coil ends
are portions of the coils not housed in the slots 1c. Likewise, as illustrated 5 in Fig. 6,
the V-phase winding 8 provided on the inner periphery of the U-phase winding 7 in
the stator core 1 is shaped such that coil ends of the inner peripheral coils 4 and coil
ends of the outer peripheral coils 3 are overlapped in a planar view, and the coil ends
of the coils configuring the V-phase winding 8 are arranged in an annular shape.
10 Likewise, as illustrated in Fig. 7, the W-phase winding 9 provided on the inner
periphery of the V-phase winding 8 in the stator core 1 is shaped such that coil ends
of the inner peripheral coils 4 and coil ends of the outer peripheral coils 3 are
overlapped in a planar view, and the coil ends of the coils configuring the W-phase
winding 9 are arranged in an annular shape.
15 [0020]
Subsequently, an example of a process of inserting the U-phase winding 7 into
the slots 1c of the stator core 1 is described. A process of inserting the V-phase
winding 8 into the slots 1c of the stator core 1 and a process of inserting the W-phase
winding 9 into the slots 1c of the stator core 1 are each similar to the process of
20 inserting the U-phase winding 7 into the slots 1c of the stator core 1. Therefore,
description of the process of inserting the V-phase winding 8 into the slots 1c of the
stator core 1 and the process of inserting the W-phase winding 9 into the slots 1c of
the stator core 1 is omitted.
[0021]
25 Fig. 8 to Fig. 10 are perspective views to explain the process of inserting the Uphase
winding into the slots of the stator core of the stator according to Embodiment
1 of the present disclosure.
In Fig. 8 to Fig. 10, to distinguish the three outer peripheral coils 3, the three
outer peripheral coils 3 are referred to as a first outer peripheral coil 3a, a second
30 outer peripheral coil 3b, and a third outer peripheral coil 3c. Likewise, in Fig. 8 to
11
Fig. 10, to distinguish the three inner peripheral coils 4, the three inner peripheral
coils 4 are referred to as a first inner peripheral coil 4a, a second inner peripheral coil
4b, and a third inner peripheral coil 4c.
[0022]
As illustrated in Fig. 8 to Fig. 10, a coil insertion jig used to 5 insert the U-phase
winding 7 into the slots 1c of the stator core 1 includes a plurality of insertion blades
13 each having a rod shape. These insertion blades 13 are arranged in an annular
shape.
[0023]
10 To insert the U-phase winding 7 into the slots 1c of the stator core 1, an electric
wire is first wound around an unillustrated bobbin to form the first inner peripheral coil
4a, the second inner peripheral coil 4b, and the third inner peripheral coil 4c.
Thereafter, as illustrated in Fig. 8, the first inner peripheral coil 4a, the second inner
peripheral coil 4b, and the third inner peripheral coil 4c are inserted into gaps among
15 the insertion blades 13, to arrange the first inner peripheral coil 4a, the second inner
peripheral coil 4b, and the third inner peripheral coil 4c.
[0024]
Next, the unillustrated bobbin is rotated by three slots around the plurality of
insertion blades 13 arranged in the annular shape. Thereafter, as illustrated in Fig.
20 9, an electric wire is wound around the unillustrated bobbin to form the first outer
peripheral coil 3a, the second outer peripheral coil 3b, and the third outer peripheral
coil 3c. Thereafter, as illustrated in Fig. 10, the first outer peripheral coil 3a, the
second outer peripheral coil 3b, and the third outer peripheral coil 3c are inserted into
the gaps among the insertion blades 13, to arrange the first outer peripheral coil 3a,
25 the second outer peripheral coil 3b, and the third outer peripheral coil 3c. As a
result, winding formation of the outer peripheral coils 3 and the inner peripheral coils 4
of the U-phase winding 7 is completed, and the outer peripheral coils 3 and the inner
peripheral coils 4 of the U-phase winding 7 are arranged at positions before being
inserted into the slots 1c.
30 [0025]
12
Because of characteristics of the electric motor, the outer peripheral coils 3 and
the inner peripheral coils 4 are desirably equal in the number of windings and in
resistance value. For example, when the outer peripheral coils 3 and the inner
peripheral coils 4 are made of the electric wire having the same diameter, and the
outer peripheral coils 3 and the inner peripheral coils 4 5 are made equal in
circumferential length, the outer peripheral coils 3 and the inner peripheral coils 4 are
equal in the number of windings and in resistance value. Further, for example, when
the outer peripheral coils 3 or the inner peripheral coils 4 are made of an electric wire
having a diameter smaller than a diameter of an electric wire configuring the other
10 coils, and are made shorter in circumferential length than the other coils, the outer
peripheral coils 3 and the inner peripheral coils 4 are similarly equal in the number of
windings and in resistance value.
[0026]
Fig. 11 is an explanatory diagram to explain a process of forming a related-art
15 wave winding. Fig. 11 illustrates the process until winding formation of the wave
winding is completed.
To form the wave winding, an electric wire is first wound in an annular shape to
form an annular coil 10 as illustrated in Fig. 11(a). Thereafter, as illustrated in Fig.
11(b), a plurality of portions on an outer periphery of the annular coil 10 are pushed
20 into an inner peripheral side to form a star-shaped coil 11 having a concave-convex
shape. As a result, winding formation of the wave winding is completed, and the
winding is formed in a shape before being inserted into the slots. Since the wave
winding is formed in such a manner, an insulation coating of the winding may be
damaged or the like by external force applied to the winding in formation of the star25
shaped coil 11, to deteriorate insulation property, which may lower reliability.
[0027]
In contrast, as described above with reference to Fig. 8 to Fig. 10, in the
process until the winding formation of the U-phase winding 7 according to
Embodiment 1 is completed, external force applied in formation of the star-shaped
30 coil 11 of the wave winding is unnecessary. Therefore, in the U-phase winding 7
13
according to Embodiment 1, it is possible to prevent the insulation property from
being lowered due to damage or the like of the insulation coating of the winding.
Likewise, in the V-phase winding 8 and the W-phase winding 9 according to
Embodiment 1, it is possible to prevent the insulation property from being lowered
due to damage or the like of the insulation coating of the winding. In 5 other words, it
is possible to prevent reliability of the stator 20 and the electric motor using the stator
20 from being lowered.
[0028]
Referring back to Fig. 10, as described above, Fig. 10 illustrates the state
10 where the winding formation of the outer peripheral coils 3 and the inner peripheral
coils 4 of the U-phase winding 7 is completed, and the outer peripheral coils 3 and the
inner peripheral coils 4 of the U-phase winding 7 are arranged at positions before
being inserted into the slots 1c. After the outer peripheral coils 3 and the inner
peripheral coils 4 of the U-phase winding 7 are arranged as illustrated in Fig. 10, the
15 outer peripheral coils 3 and the inner peripheral coils 4 are inserted into the slots 1c
by using an insertion stripper 14 of the coil insertion jig illustrated in Fig. 10. More
specifically, the stator core 1 is first disposed above the outer peripheral coils 3 and
the inner peripheral coils 4. Thereafter, the insertion stripper 14 disposed below the
outer peripheral coils 3 and the inner peripheral coils 4 is gradually raised to push up
20 the outer peripheral coils 3 and the inner peripheral coils 4. As a result, the outer
peripheral coils 3 and the inner peripheral coils 4 are inserted into the slots 1c.
When the outer peripheral coils 3 and the inner peripheral coils 4 are pushed up while
a part or all of the insertion blades 13 are fixed to the insertion stripper 14, the
insertion blades 13 may be moved together with the insertion stripper 14.
25 [0029]
Fig. 12 is an explanatory diagram to explain a process of forming a related-art
concentric winding.
In the related-art concentric winding provided in a stator that includes 18 slots,
three phases, and six poles, a winding of each of the phases includes three coils 12.
30 Fig. 12 illustrates the three coils 12 of a U-phase winding of the related-art concentric
14
winding.
[0030]
When the U-phase winding of the related-art concentric winding is inserted into
the slots of the stator core, an electric wire is first wound around an unillustrated
bobbin to form the three coils 12. Thereafter, as illustrated in Fig. 5 12, the coils 12
are inserted into the gaps among the insertion blades 13 arranged in the annular
shape. Thereafter, the coils 12 are pushed up by the unillustrated insertion stripper
14 to insert the coils 12 into the slots. As described above, the U-phase winding 7,
the V-phase winding 8, and the W-phase winding 9 of the stator 20 according to
10 Embodiment 1 can be inserted into the slots 1c of the stator core 1 by using the coil
insertion jig used in the related art.
[0031]
When the outer peripheral coils 3 and the inner peripheral coils 4 of the Uphase
winding 7 are inserted into the slots 1c in the manner described above with
15 reference to Fig. 8 to Fig. 10, and the coil ends of the U-phase winding 7 are formed
in the annular shape, the stator illustrated in Fig. 5 is obtained. When the outer
peripheral coils 3 and the inner peripheral coils 4 of the V-phase winding 8 are
inserted into the slots 1c as described above in this state, and the coil ends of the Vphase
winding 8 are formed in the annular shape, the stator illustrated in Fig. 6 is
20 obtained. Further, when the outer peripheral coils 3 and the inner peripheral coils 4
of the W-phase winding 9 are inserted into the slots 1c as described above in this
state, and the coil ends of the W-phase winding 9 are formed in the annular shape,
the stator illustrated in Fig. 7 is obtained. Note that at least two of the U-phase
winding 7, the V-phase winding 8, and the W-phase winding 9 may be inserted into
25 the slots 1c at the same time, and the coil ends of these windings may be formed in
the annular shape.
[0032]
Fig. 13 is a plan view of the stator according to Embodiment 1 of the present
disclosure. Fig. 14 is a plan view of a stator using a related-art concentric winding.
30 As illustrated in Fig. 14, in the stator using the related-art concentric winding, a
15
width of each coil of the winding of each phase in a planar view is defined as L. In
other words, in the stator using the related-art concentric winding, a diameter of each
coil of the winding of each phase is defined as L. In this case, in the stator using the
related-art concentric winding, a width of each coil end of the winding of each phase
in a planar view is also L. In addition, in the stator using the related-5 art concentric
winding, the coil ends of the windings of up to two phases are overlapped in the radial
direction of the stator core. Therefore, in the stator using the related-art concentric
winding, the maximum width of each coil end in a planar view is 2L.
[0033]
10 In contrast, in the stator 20 according to Embodiment 1, the number of coils of
the winding of each phase is twice the number of coils in the related art.
Accordingly, in the stator 20 according to Embodiment 1, the number of windings of
each coil of the winding of each phase is half of the number of windings in the related
art, and the width of each coil of the winding of each phase in a planar view is L/2.
15 Therefore, in a case where, in the stator 20 according to Embodiment 1, the length of
each coil of the winding of each phase in the axial direction of the stator core 1 is
made equal to a length in the related art, the width of each coil end of the winding of
each phase in planar view is L/2. In addition, in the stator 20 according to
Embodiment 1, the coil ends of the windings of the three phases are overlapped in
20 the radial direction of the stator core 1. Therefore, in the stator 20 according to
Embodiment 1, a total width of the coil ends in a planar view is 3L/2. As described
above, in the stator 20 according to Embodiment 1, the coil ends can be downsized
as compared with the stator using the related-art concentric winding. Thus, in the
stator 20 according to Embodiment 1, it is possible to reduce the resistance value of
25 the windings as compared with the stator using the related-art concentric winding. In
other words, the stator 20 according to Embodiment 1 can realize downsizing and
high performance of the electric motor, as compared with the stator using the relatedart
concentric winding.
[0034]
30 Note that the case where the length of each coil of the winding of each phase
16
in the axial direction of the stator core 1 is made equal to the length in the related art
indicates a case where the coil ends of the outer peripheral coils 3 and the coil ends
of the inner peripheral coils 4 are overlapped in the axial direction of the stator core 1,
and the length of the coil ends of the winding of each phase in the axial direction of
the stator core 5 1 is made to L.
[0035]
As described above, the stator 20 according to Embodiment 1 includes the
stator core 1 that has a hollow cylindrical shape and includes the plurality of slots 1c
arranged on the inner periphery at prescribed intervals in the circumferential direction,
10 and the distributed concentric windings wound through the slots 1c. Further, in the
stator 20 according to Embodiment 1, the number of slots per pole and phase is one,
and the winding of each phase includes the same number of coils as the number of
poles. Half of the coils of the winding of each phase are the outer peripheral coils 3
and are arranged on the outer peripheral side of the inner peripheral coils 4 that are
15 remaining half of the coils of the winding of each phase. Further, the outer
peripheral coils 3 and the inner peripheral coils 4 are alternately arranged in the
circumferential direction of the stator core 1. When one of the outer peripheral coils
3 and one of the inner peripheral coils 4 adjacent to each other are viewed, a part of
the outer peripheral coil 3 and a part of the inner peripheral coil 4 are housed in the
20 same slot 1c, and the coil ends of the coils configuring the winding of each phase are
arranged in the annular shape.
[0036]
The stator 20 according to Embodiment 1 includes the distributed windings.
When the coils of the winding of each phase are arranged as in the stator 20
25 according to Embodiment 1, the coil ends can be downsized and the coil
circumferential length can be reduced. This makes it possible to reduce the
resistance value of the windings. Therefore, using the stator 20 according to
Embodiment 1 makes it possible to realize downsizing and high performance of the
electric motor. Further, the winding of the stator 20 according to Embodiment 1 is
30 the concentric winding. In formation of the concentric winding, external force applied
17
when the star-shaped coil of the wave winding is unnecessary. Accordingly, using
the stator 20 according to Embodiment 1 makes it possible to prevent the reliability of
the electric motor from being lowered.
[0037]
Further, in the stator 20 according to Embodiment 1, the 5 coil ends can be
downsized as compared with the stator using the related-art concentric winding.
This makes it possible to reduce a use amount of the electric wire. Thus, the stator
20 according to Embodiment 1 can be manufactured at low cost as compared with
the stator using the related-art concentric winding.
10 [0038]
Further, since the stator 20 according to Embodiment 1 uses the concentric
winding, the stator 20 according to Embodiment 1 can be manufactured at low cost as
compared with a stator using a wave winding or a lap winding, while having
advantage of the wave winding enabling reduction in coil circumferential length and
15 advantage of the lap winding enabling downsizing of the coil ends. More specifically,
to form the wave winding, the process of forming the star-shaped coil 11 is necessary
in addition to the process of winding the electric wire to form the annular coil 10 as
described above. Therefore, a winding device forming the wave winding is
increased in size, and occupancy of a production site by the winding device is
20 increased. Moreover, a jig forming the star-shaped coil 11 has a complicated
structure. Therefore, if the stator having the different number of slots is
manufactured, a work of changing the number of jigs forming the concave-convex
portions of the star-shaped coil 11 or other work is not easy. Therefore, the stator
using the wave winding is expensive.
25 [0039]
To form the lap winding, a process of dividing a winding unit in which the
electric wire is wound in a spiral shape by every predetermined winding quantity is
necessary. Further, to form the lap winding, it is necessary to regularly arrange the
two coils inserted into the same slots of the stator core, on the outer periphery and
30 the inner periphery. Therefore, it is necessary to attach the coils to the coil insertion
18
jig in a regular arrangement similar to the arrangement of the coils. The coil
positions when the coils are attached to the coil insertion jig are corrected manually or
by an expensive winding device provided with a correction mechanism having a
complicated structure. Therefore, the stator using the lap winding is expensive.
5 [0040]
In contrast, the stator 20 according to Embodiment 1 can be formed by using
the related-art facilities and jigs for the related-art concentric winding as they are.
Further, the jig itself used for the winding formation of the concentric winding has a
simple structure. In addition, it is possible to cope with the different shape of the
10 stator core 1 and change in the number of slots 1c by replacing the inexpensive jig
having the simple structure, such as the above-described coil insertion jig. The
winding device has versatility applicable to a large number of models. Since the
stator 20 according to Embodiment 1 uses the concentric winding, the stator 20
according to Embodiment 1 can be manufactured at low cost as compared with a
15 stator using a wave winding or a lap winding, while having advantage of the wave
winding enabling reduction in coil circumferential length and advantage of the lap
winding enabling downsizing of the coil ends.
[0041]
Embodiment 2
20 In Embodiment 2, an example of a wire connection structure of the coils of the
stator 20 described in Embodiment 1. Note that, in Embodiment 2, items not
specifically described are similar to the items in Embodiment 1, and the functions and
configurations same as the functions and configurations in Embodiment 1 are
denoted by the same reference numerals.
25 [0042]
Fig. 15 is a diagram illustrating an example of a wire connection structure of a
stator according to Embodiment 2 of the present disclosure.
As illustrated in Fig. 1 and Fig. 4, in a case where the number of slots 1c is 18,
each of the U-phase winding 7, the V-phase winding 8, and the W-phase winding 9
30 includes the three outer peripheral coils 3 and the three inner peripheral coils 4. As
19
illustrated in Fig. 15, each of the outer peripheral coils 3 of each phase is connected
to the adjacent outer peripheral coil 3 through a jumper wire 3f. In other words, the
outer peripheral coils 3 of each phase are connected in series by the jumper wires 3f.
More specifically, among the outer peripheral coils 3 of each phase, a lead wire of the
first outer peripheral coil 3a and a lead wire of the second outer peripheral 5 coil 3b are
connected by the jumper wire 3f. Among the outer peripheral coils 3 of each phase,
a lead wire of the second outer peripheral coil 3b and a lead wire of the third outer
peripheral coil 3c are connected by the jumper wire 3f.
[0043]
10 Further, as illustrated in Fig. 15, each of the inner peripheral coils 4 of each
phase is connected to the adjacent inner peripheral coil 4 by a jumper wire 4f. In
other words, the inner peripheral coils 4 of each phase are connected in series by the
jumper wires 4f. More specifically, among the inner peripheral coils 4 of each phase,
a lead wire of the first inner peripheral coil 4a and a lead wire of the second inner
15 peripheral coil 4b are connected by the jumper wire 4f. Among the inner peripheral
coils 4 of each phase, a lead wire of the second inner peripheral coil 4b and a lead
wire of the third inner peripheral coil 4c are connected by the jumper wire 4f.
[0044]
Further, lead wires 3e of the third outer peripheral coils 3c of the respective
20 phases are short-circuited to form a neutral point 15a. Lead wires 4d of the first
inner peripheral coils 4a of the respective phases are short-circuited to form a neutral
point 15b. In Embodiment 2, the lead wires 3e of the third outer peripheral coils 3c
are lead wires at winding end of the third outer peripheral coils 3c. The lead wires
4d of the first inner peripheral coils 4a are lead wires at winding start of the first inner
25 peripheral coils 4a.
[0045]
Further, the lead wire 3d of the first outer peripheral coil 3a and the lead wire
4e of the third inner peripheral coil 4c of each phase are short-circuited, and a shortcircuited
point is connected to a power supply through a lead wire 16. More
30 specifically, in the U-phase winding 7, the lead wire 3d of the first outer peripheral coil
20
3a and the lead wire 4e of the third inner peripheral coil 4c are short-circuited, and a
short-circuited point is connected to the power supply through a U-phase lead wire
16a. In the V-phase winding 8, the lead wire 3d of the first outer peripheral coil 3a
and the lead wire 4e of the third inner peripheral coil 4c are short-circuited, and a
short-circuited point is connected to the power supply through a 5 V-phase lead wire
16b. In the W-phase winding 9, the lead wire 3d of the first outer peripheral coil 3a
and the lead wire 4e of the third inner peripheral coil 4c are short-circuited, and a
short-circuited point is connected to the power supply through a W-phase lead wire
16c. In Embodiment 2, the lead wires 3d of the first outer peripheral coils 3a are
10 lead wires at winding start of the first outer peripheral coils 3a. The lead wires 4e of
the third inner peripheral coils 4c are lead wires at winding end of the third inner
peripheral coils 4c.
[0046]
As described above, the coils of the stator 20 according to Embodiment 2 are
15 arranged in a three-phase Y-connection structure by two parallel circuits. The threephase
Y-connection structure by the two parallel circuits is also written as a 2//Y
connection structure.
[0047]
As illustrated in Fig. 12, in the related-art concentric winding provided in the
20 stator that includes 18 slots, three phases, and six poles, the winding of each of the
phases includes an odd number of coils, namely, the three coils. Therefore, in the
stator using the related-art concentric winding, the coils are arranged in a Yconnection
structure in which the coils of each phase are connected in series or in a
three-phase Y-connection structure by three parallel circuits in which the coils of each
25 phase are connected in parallel. The three-phase Y-connection structure by the
three parallel circuits is also written as a 3//Y connection structure. In other words, in
the stator using the related-art concentric winding, the wire connection structure of the
coils has only two options.
[0048]
30 In contrast, in the stator 20 according to Embodiment 2, the winding of each of
21
the phases includes an even number of coils, namely, the six coils. Therefore, the
stator 20 according to Embodiment 2 can adopt the 2//Y connection structure as
described above, in addition to the wire connection structure of the stator using the
related-art concentric winding. Accordingly, the stator 20 configured as in
Embodiment 2 can realize an effect of increasing the number of options 5 of the wire
connection structure of the coils and increasing a degree of freedom in design, in
addition to the effects described in Embodiment 1.
[0049]
Embodiment 3
10 In Embodiment 3, in the winding formation of the plurality of outer peripheral
coils 3 of each phase, a method of forming the plurality of outer peripheral coils 3
without separating the outer peripheral coils 3, to form the jumper wires 3f by the
electric wire in the winding formation is described. Likewise, in Embodiment 3, in the
winding formation of the plurality of inner peripheral coils 4 of each phase, a method
15 of forming the plurality of inner peripheral coils 4 without separating the inner
peripheral coils 4, to form the jumper wires 4f by the electric wire in the winding
formation is described. Further, in Embodiment 3, preferred arrangement of the lead
wires of the outer peripheral coils 3 and the inner peripheral coils 4 connected to the
power supply is described. Note that, in Embodiment 3, items not specifically
20 described are similar to the items in Embodiment 1 or Embodiment 2, and the
functions and configurations same as the functions and configurations in Embodiment
1 or Embodiment 2 are denoted by the same reference numerals.
[0050]
Fig. 16 is a perspective view to explain an example of a stator according to
25 Embodiment 3 of the present disclosure and illustrating a stator core and a part of a
winding.
In Embodiment 3, the winding illustrated in Fig. 16 is the U-phase winding 7.
As illustrated in Fig. 16, the first outer peripheral coil 3a and the second outer
peripheral coil 3b are connected by the jumper wire 3f. The second outer peripheral
30 coil 3b and the third outer peripheral coil 3c are connected by the jumper wire 3f.
22
These jumper wires 3f are formed by continuously forming the coils without cutting
the electric wire between the coils when the first outer peripheral coil 3a, the second
outer peripheral coil 3b, and the third outer peripheral coil 3c are formed by winding.
[0051]
Likewise, the first inner peripheral coil 4a and the second inner 5 peripheral coil
4b are connected by the jumper wire 4f. The second inner peripheral coil 4b and the
third inner peripheral coil 4c are connected by the jumper wire 4f. These jumper
wires 4f are formed by continuously forming the coils without cutting the electric wire
between the coils when the first inner peripheral coil 4a, the second inner peripheral
10 coil 4b, and the third inner peripheral coil 4c are formed by winding.
More specifically, the outer peripheral coils 3 and the inner peripheral coils 4
are formed by winding in the following manner.
[0052]
Fig. 17 to Fig. 19 are perspective views to explain a process of winding the U15
phase winding of the stator according to Embodiment 3 of the present disclosure.
A process of winding the V-phase winding 8 and a process of winding the Wphase
winding 9 are each similar to the process of winding the U-phase winding 7.
[0053]
As illustrated in Fig. 17, the electric wire is wound around an unillustrated
20 bobbin while leaving a portion of the electric wire to be the lead wire 4b, to form the
first inner peripheral coil 4a. Thereafter, the first inner peripheral coil 4a is inserted
into the gaps among the insertion blades 13. Next, the unillustrated bobbin is
rotated around the plurality of insertion blades 13 arranged in the annular shape.
The electric wire is then wound around the unillustrated bobbin without cutting the
25 electric wire after formation of the first inner peripheral coil 4a, to form the second
inner peripheral coil 4b. Thereafter, the second inner peripheral coil 4b is inserted
into the gaps among the insertion blades 13. Next, the unillustrated bobbin is
rotated around the plurality of insertion blades 13 arranged in the annular shape.
The electric wire is then wound around the unillustrated bobbin without cutting the
30 electric wire after formation of the second inner peripheral coil 4b, to form the third
23
inner peripheral coil 4c. Thereafter, the third inner peripheral coil 4c is inserted into
the gaps among the insertion blades 13. Finally, after the third inner peripheral coil
4c is inserted into the gaps among the insertion blades 13, the electric wire is cut
while leaving a portion of the electric wire to be the lead wire 4e.
5 [0054]
Subsequently, as illustrated in Fig. 18 and Fig. 19, the first outer peripheral coil
3a, the second outer peripheral coil 3b, and the third outer peripheral coil 3c are
formed by winding, and are inserted into the gaps among the insertion blades 13.
More specifically, the electric wire is wound around an unillustrated bobbin while
10 leaving a portion of the electric wire to be the lead wire 3b, to form the first outer
peripheral coil 3a. Thereafter, the first outer peripheral coil 3a is inserted into the
gaps among the insertion blades 13. Next, the unillustrated bobbin is rotated around
the plurality of insertion blades 13 arranged in the annular shape. The electric wire
is then wound around the unillustrated bobbin without cutting the electric wire after
15 formation of the first outer peripheral coil 3a, to form the second outer peripheral coil
3b. Thereafter, the second outer peripheral coil 3b is inserted into the gaps among
the insertion blades 13. Next, the unillustrated bobbin is rotated around the plurality
of insertion blades 13 arranged in the annular shape. The electric wire is then
wound around the unillustrated bobbin without cutting the electric wire after formation
20 of the second outer peripheral coil 3b, to form the third outer peripheral coil 3c.
Thereafter, the third outer peripheral coil 3c is inserted into the gap among the
insertion blades 13. Finally, after the third outer peripheral coil 3c is inserted into the
gap among the insertion blades 13, the electric wire is cut while leaving a portion of
the electric wire to be the lead wire 3e. As a result, the outer peripheral coils 3 and
25 the inner peripheral coils 4 are arranged as illustrated in Fig. 19.
[0055]
Fig. 18 illustrates a state where, after the winding formation of the first outer
peripheral coil 3a, the second outer peripheral coil 3b, and the third outer peripheral
coil 3c is completed, these coils are not inserted into the gaps among the insertion
30 blades 13. Fig. 18 illustrates a conceptual image after the winding formation of the
24
first outer peripheral coil 3a, the second outer peripheral coil 3b, and the third outer
peripheral coil 3c is completed. As described above, each of the second outer
peripheral coil 3b, and the third outer peripheral coil 3c is actually inserted into the
gaps among the insertion blades 13 after the winding formation of one coil is
5 completed.
[0056]
After the outer peripheral coils 3 and the inner peripheral coils 4 are arranged
as illustrated in Fig. 19, the outer peripheral coils 3 and the inner peripheral coils 4
are inserted into the slots 1c in the manner described in Embodiment 1. As a result,
10 the stator 20 illustrated in Fig. 16 is obtained. In Fig. 16, the lead wire 3d of the
outer peripheral coil 3 and the lead wire 4e of the inner peripheral coil 4 are disposed
in the same slot 1c.
[0057]
Phases of the outer peripheral coils 3 to the inner peripheral coils 4 may be
15 changed from the phases illustrated in Fig. 16, with the axis of the stator core 1 as a
rotation center.
[0058]
Fig. 20 is a perspective view to explain another example of the stator according
to Embodiment 3 of the present disclosure and illustrating the stator core and the U20
phase winding.
In the stator 20 illustrated in Fig. 16, the second outer peripheral coil 3b is
disposed between the first inner peripheral coil 4a and the second inner peripheral
coil 4b. In contrast, in the stator 20 illustrated in Fig. 20, the first outer peripheral coil
3a is disposed between the first inner peripheral coil 4a and the second inner
25 peripheral coil 4b. Such outer peripheral coils 3 and inner peripheral coils 4 are
formed by winding in the following manner.
[0059]
Fig. 21 and Fig. 22 are perspective views to explain a process of winding the
U-phase winding of the stator illustrated in Fig. 20.
30 A process of winding the V-phase winding 8 and a process of winding the W25
phase winding 9 are each similar to the process of winding the U-phase winding 7.
[0060]
The winding formation of the outer peripheral coils 3 and the inner peripheral
coils 4 of the U-phase winding 7 of the stator 20 illustrated in Fig. 20 is performed
similarly to the process illustrated in Fig. 17 to Fig. 19 except 5 for arrangement
positions of the outer peripheral coils 3 to the inner peripheral coils 4. More
specifically, in the process illustrated in Fig. 17 to Fig. 19, the second outer peripheral
coil 3b is disposed between the first inner peripheral coil 4a and the second inner
peripheral coil 4b. In contrast, as illustrated in Fig. 21 and Fig. 22, in the process of
10 winding the outer peripheral coils 3 of the U-phase winding 7 of the stator 20
illustrated in Fig. 20, the first outer peripheral coil 3a is disposed between the first
inner peripheral coil 4a and the second inner peripheral coil 4b.
[0061]
After the outer peripheral coils 3 and the inner peripheral coils 4 are arranged
15 as illustrated in Fig. 22, the outer peripheral coils 3 and the inner peripheral coils 4
are inserted into the slots 1c in the manner described in Embodiment 1. As a result,
the stator 20 illustrated in Fig. 120 is obtained. In Fig. 20, the lead wire 3e of the
outer peripheral coil 3 and the lead wire 4d of the inner peripheral coil 4 are disposed
in the same slot 1c.
20 [0062]
When the lead wire of the outer peripheral coil 3 and the lead wire of the inner
peripheral coil 4 are disposed in the same slot 1c as in the stator 20 according to
Embodiment 3, the following effects are achievable.
[0063]
25 In the stator 20 illustrated in Fig. 16, the lead wire 3d of the first outer
peripheral coil 3a that is disposed in the same slot 1c as the lead wire 4e of the third
inner peripheral coil 4c is disposed at an end part 3g on the third inner peripheral coil
4c side, of an end part of the first outer peripheral coil 3a in the radial direction of the
stator core 1. Further, the lead wire 4e of the third inner peripheral coil 4c that is
30 disposed in the same slot 1c as the lead wire 3d of the first outer peripheral coil 3a is
26
disposed at an end part 4g on the first outer peripheral coil 3a side, of an end part of
the third inner peripheral coil 4c in the radial direction of the stator core 1.
[0064]
In a case where the coils of the stator 20 illustrated in Fig. 16 are connected as
illustrated in Fig. 15, a connection work is performable while regarding 5 the lead wire
3d of the first outer peripheral coil 3a and the lead wire 4e of the third inner peripheral
coil 4c of the same phase, as one lead wire. This makes it possible to eliminate a
connection work for the lead wire 3d and the lead wire 4e and an insulation part used
at a connection portion between the lead wire 3d and the lead wire 4e. Therefore, in
10 the case where the coils of the stator 20 illustrated in Fig. 16 are connected as
illustrated in Fig. 15, assembling workability of the stator 20 is improved, and the
stator 20 can be manufactured at low cost.
[0065]
In the stator 20 illustrated in Fig. 20, the lead wire 3e of the third outer
15 peripheral coil 3c that is disposed in the same slot 1c as the lead wire 4d of the first
inner peripheral coil 4a is disposed at an end part 3h on a side opposite to the first
inner peripheral coil 4a, of an end part of the third outer peripheral coil 3c in the radial
direction of the stator core 1. Further, the lead wire 4d of the first inner peripheral
coil 4a that is disposed in the same slot 1c as the lead wire 3e of the third outer
20 peripheral coil 3c is disposed at an end part 4h on a side opposite to the third outer
peripheral coil 3c, of an end part of the first inner peripheral coil 4a in the radial
direction of the stator core 1.
[0066]
Fig. 23 is a diagram illustrating an example of a wire connection structure of the
25 stator illustrated in Fig. 20.
In a case where a current capacity of the electric motor is large or other cases,
the plurality of coils configuring each phase are connected to the power supply by a
plurality of lead wires in some cases. For example, there is a case where the coils of
the stator 20 illustrated in Fig. 20 are connected as illustrated in Fig. 23. More
30 specifically, there is a case where the lead wire 3e of the third outer peripheral coil 3c
27
and the lead wire 4d of the first inner peripheral coil 4a of the same phase are
connected to the power supply by different lead wires 16. In such a case, when the
stator 20 is configured as illustrated in Fig. 20, the lead wire 3e and the lead wire 4d
are clearly distinguished from each other. This makes it possible to prevent incorrect
lead wires 16 from being connected to the lead wire 3e and the lead 5 wire 4d, which
facilitates connection of correct lead wires 16 to the lead wire 3e and the lead wire 4d.
[0067]
Therefore, in the case where the coils of the stator 20 illustrated in Fig. 20 are
connected as illustrated in Fig. 20, assembling workability of the stator 20 is
10 improved, and the stator 20 can be manufactured at low cost. Further, in the case
where the coils of the stator 20 illustrated in Fig. 20 are connected as illustrated in
Fig. 23, it is possible to improve reliability of the stator 20. At this time, in a case
where the outer peripheral coils 3 are made of an electric wire having a diameter
different from a diameter of an electric wire configuring the inner peripheral coils 4,
15 currents of different magnitudes are supplied to the outer peripheral coils 3 and the
inner peripheral coils 4. Therefore, facilitation of connection of the correct lead wires
16 to the lead wire 3e and the lead wire 4d is particularly useful in the case where the
outer peripheral coils 3 are made of an electric wire having a diameter different from a
diameter of an electric wire configuring the inner peripheral coils 4.
20 [0068]
Embodiment 4
In Embodiment 4, an example of an electric motor using the stator 20
described in any of Embodiments 1 to 3 is described. Note that, in Embodiment 4,
items not specifically described are similar to the items in any of Embodiments 1 to 3,
25 and the functions and configurations same as the functions and configurations in any
of Embodiments 1 to 3 are denoted by the same reference numerals.
[0069]
Fig. 24 is a cross-sectional view illustrating an example of an electric motor
according to Embodiment 4 of the present disclosure. Fig. 24 is a cross-sectional
30 view of an electric motor 30 taken along a virtual plane parallel to a rotation center of
28
a rotor 31.
The electric motor 30 includes the stator 20 described in any of Embodiments 1
to 3, and the rotor 31 rotatably disposed on the inner periphery of the stator 20. A
through hole 31a to which an output shaft is fixed is provided at a center of the rotor
31 along the rotation center of the rotor 31. The electric motor 30 5 is, for example, a
synchronous electric motor in which the rotor 31 includes a permanent magnet.
When a current flows through each of the U-phase winding 7, the V-phase winding 8,
and the W-phase winding 9 of the stator 20, a magnetic field is generated, and a
rotation torque is generated on the rotor 31 by the magnetic field. As a result, the
10 rotor 31 is rotated.
[0070]
As described above, the electric motor 30 according to Embodiment 4 includes
the stator 20 described in any of Embodiments 1 to 3. Therefore, the electric motor
30 can realize downsizing and high performance, and can prevent reliability from
15 being lowered.
[0071]
Embodiment 5
In Embodiment 5, an example of a compressor using the electric motor 30
described in Embodiment 4 is described. Note that, in Embodiment 5, items not
20 specifically described are similar to the items in any of Embodiments 1 to 4, and the
functions and configurations same as the functions and configurations in any of
Embodiments 1 to 4 are denoted by the same reference numerals.
[0072]
Fig. 25 is a vertical cross-sectional view illustrating an example of a
25 compressor according to Embodiment 5 of the present disclosure.
A compressor 40 includes the electric motor 30 described in Embodiment 4,
and a compression mechanism 41. The electric motor 30 and the compression
mechanism 41 are connected by a driving shaft 42 fixed to the rotor 31. The driving
shaft 42 is the output shaft fixed to the through hole 31a of the rotor 31 illustrated in
30 Fig. 24. The compressor 40 further includes a sealed container 43. The electric
29
motor 30, the compression mechanism 41, and the driving shaft 42 are housed in the
sealed container 43.
[0073]
When a current flows through each of the U-phase winding 7, the V-phase
winding 8, and the W-phase winding 9 of the stator 20, a magnetic field 5 is generated,
and a rotation torque is generated on the rotor 31 by the magnetic field. As a result,
the rotor 31 is rotated. Driving force of the electric motor 30 is transmitted to the
compression mechanism 41 through the driving shaft 42 that is fixed to the rotor 31
and is rotated together with the rotor 31. Further, the compression mechanism 41
10 suctions refrigerant to an inside by the driving force of the electric motor 30, and
compresses the suctioned refrigerant. More specifically, when the driving force of
the electric motor 30 is transmitted to the compression mechanism 41, the refrigerant
is suctioned into the compression mechanism 41 through a suction pipe 44.
Thereafter, the suctioned refrigerant is compressed by the compression mechanism
15 41, and is then discharged from the compression mechanism 41 into the sealed
container 43. The discharged refrigerant passes through a space between the stator
20 and the rotor 31, and other spaces, and then flows out from a discharge pipe 45 to
outside of the compressor 40.
[0074]
20 The compression mechanism 41 according to Embodiment 5 is a twin rotary
compression mechanism; however, a type of the compression mechanism 41 is
optional. Any of various well-known compression mechanisms such as a single
rotary compression mechanism, a scroll compression mechanism, and a screw
compression mechanism is usable as the compression mechanism 41.
25 [0075]
As described above, the compressor 40 according to Embodiment 5 includes
the electric motor 30 described in Embodiment 4. Therefore, the compressor 40 can
realize downsizing and high performance, and can prevent reliability from being
lowered.
30 [0076]
30
Further, as illustrated in Fig. 13, in the stator 20 of the electric motor 30, a gap
provided between the coil ends of the respective coils is decreased. Therefore, a
collection of the coil ends of the coils forms a cylindrical wall on an inner diameter
side. This smooths a flow of the refrigerant passing through the space between the
stator 20 and the rotor 31. Improvement of the flow of the refrigerant 5 passing
through the space between the stator 20 and the rotor 31 also improves performance
of the compressor 40 according to Embodiment 5.
Reference Signs List
[0077]
10 1: stator core, 1a: back yoke, 1b: tooth, 1c: slot, 1d: through hole, 2: slot film, 3:
outer peripheral coil, 3a: first outer peripheral coil, 3b: second outer peripheral coil,
3c: third outer peripheral coil, 3d: lead wire, 3e: lead wire, 3f: jumper wire, 3g: end
part, 3h: end part, 4: inner peripheral coil, 4a: first inner peripheral coil, 4b: second
inner peripheral coil, 4c: third inner peripheral coil, 4d: lead wire, 4e: lead wire, 4f:
15 jumper wire, 4g: end part, 4h: end part, 7: U-phase winding, 8: V-phase winding, 9:
W-phase winding, 10: annular coil, 11: star-shaped coil, 12: coil, 13: insertion blade,
14: insertion stripper, 15a: neutral point, 15b: neutral point, 16: lead wire, 16a: Uphase
lead wire, 16b: V-phase lead wire, 16c: W-phase lead wire, 20: stator, 30:
electric motor, 31: rotor, 31a: through hole, 40: compressor, 41: compression
20 mechanism, 42: driving shaft, 43: sealed container, 44: suction pipe, 45: discharge
pipe
31
We Claim :
[Claim 1]
A stator, comprising:
a stator core having a hollow cylindrical shape and including a plurality of slots
arranged on an inner periphery at prescribed intervals in a circumferential 5 direction;
and
distributed concentric windings wound through the slots, wherein
the number of slots per pole and phase is one,
the winding of each phase includes same number of coils as the number of
10 poles,
half of the coils are outer peripheral coils and are arranged on an outer
peripheral side of inner peripheral coils that are remaining half of the coils,
the outer peripheral coils and the inner peripheral coils are alternately arranged
in the circumferential direction,
15 when one of the outer peripheral coils and one of the inner peripheral coils
adjacent to each other are viewed, a part of the outer peripheral coil and a part of the
inner peripheral coil are housed in a same slot, and
coil ends of the coils configuring the winding of each phase are arranged in an
annular shape.
20 [Claim 2]
The stator of claim 1, wherein the outer peripheral coils and the inner
peripheral coils are equal in number of windings and in resistance value.
[Claim 3]
The stator of claim 1 or 2, wherein
25 the winding of each phase includes the plurality of outer peripheral coils and
the plurality of inner peripheral coils,
each of the outer peripheral coils is connected to the adjacent outer peripheral
coil by a jumper wire, and
each of the inner peripheral coils is connected to the adjacent inner peripheral
30 coil by a jumper wire.
32
[Claim 4]
The stator of any one of claims 1 to 3, wherein
the outer peripheral coils have a lead wire and the inner peripheral coils have a
lead wire, and
the lead wire of the outer peripheral coils and the lead 5 wire of the inner
peripheral coils are disposed on a same slot.
[Claim 5]
The stator of claim 4, wherein
the lead wire of the outer peripheral coils is disposed at an end part on the
10 inner peripheral coil side, of an end part of the outer peripheral coils in a radial
direction of the stator core, and
the lead wire of the inner peripheral coils is disposed at an end part on the
outer peripheral coil side, of an end part of the inner peripheral coils in the radial
direction.
15 [Claim 6]
The stator of claim 4, wherein
the lead wire of the outer peripheral coils is disposed at an end part on a side
opposite to the inner peripheral coils, of an end part of the outer peripheral coils in a
radial direction of the stator core, and
20 the lead wire of the inner peripheral coils is disposed at an end part on a side
opposite to the outer peripheral coils, of an end part of the inner peripheral coils in the
radial direction.
[Claim 7]
An electric motor, comprising:
25 the stator of any one of claims 1 to 6; and
a rotor disposed on an inner periphery of the stator.
[Claim 8]
A compressor, comprising:
the electric motor of claim 7; and
30 a compression mechanism configured to compress refrigerant by driving force
33
of the electric motor.