FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
ELECTRIC MOTOR FOR COMPRESSOR, COMPRESSOR, REFRIGERATION
CYCLE APPARATUS, AND METHOD FOR MANUFACTURING ELECTRIC MOTOR
FOR 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
Technical Field
[0001]
The present disclosure relates to an electric motor for a compressor, the
5 compressor, a refrigeration cycle apparatus, and a method for manufacturing the
electric motor for the compressor, the electric motor including a plurality of electric
winding wires.
Background Art
[0002]
10 In general, an electric motor for a compressor (which will hereinafter be
referred to as an electric motor) includes a plurality of electric winding wires that form
a winding portion of a stator. In such an electric motor, the electric winding wires are
joined together, and a joint portion thereof is covered by an insulating material, such
as insulating paper. An assembly of a plurality of electric winding wires joined
15 together is disclosed (see, for example, Patent Literature 1). The assembly
disclosed in Patent Literature 1 is configured such that a first exposed core wire
portion and a second exposed core wire portion are joined together. The first
exposed core wire portion is exposed from a first covering portion of a first electric
wire, and the second exposed core wire portion is exposed from a second covering
20 portion of a second electric wire. In Patent Literature 1, the first exposed core wire
portion and the second exposed core wire portion are joined together such that the
second exposed core wire portion is located in a space between both sides of the first
exposed core wire portion which is U-shaped, or the first exposed core wire portion is
helically wound around an outer periphery of the second exposed core wire portion
25 that excludes a distal end portion thereof.
Citation List
Patent Literature
[0003]
Patent Literature 1: Japanese Unexamined Patent Application Publication No.
30 2017-76497
3
Summary of Invention
Technical Problem
[0004]
In general, an end surface of the first exposed core wire portion is made wider
5 in width than the vicinity of a distal end of the first exposed core wire portion by a
force which is applied thereto when the first electric wire is cut, and projections are
formed on both sides of the end surface in the width direction. Similarly, an end
surface of the second exposed core wire portion is made wider in width than the
vicinity of a distal end of the second exposed core wire portion by a force which is
10 applied thereto when the second electric wire is cut, and projections are formed on
the both sides of the end surface in the width direction. Therefore, in a configuration
in which the second exposed core wire portion is located between U-shaped portions
of the first exposed core wire portion as described in Patent Literature 1, although a
central portion of the end surface in the width direction is covered by the second
15 exposed core wire portion, the projections on the both sides of the end surface in the
width direction protrude from the second exposed core wire portion. Furthermore, in
the configuration in which the first exposed core wire portion is helicaly wound
around the outer periphery of the second exposed core wire portion that excludes the
distal end portion as described in Patent Literature 1, an edge portion of the end
20 surface of the second exposed core wire portion is exposed. Therefore, the
projections on the both sides of the end surface in the width direction protrude from
the first exposed core wire portion. Thus, in both the configurations described in
Patent Literature 1, the projections may penetrate the insulating material which
covers the joint portion of the first and second exposed core wire portions, and an
25 insulation failure may occur.
[0005]
The present disclosure is applied to solve the above problems, and relates to
an electric motor for a compressor, the compressor, a refrigeration cycle apparatus,
and a method for manufacturing the electric motor for the compressor, which all
30 reduce occurrence of an insulation failure.
4
Solution to Problem
[0006]
An electric motor for a compressor according to one embodiment of the present
disclosure includes a stator including a stator winding. The stator winding includes:
5 a first electric wire bundle having a first end portion and a first end face, the first end
portion including end portions of a plurality of first electric wires and being formed in
the shape of a wire bundle, the end portions of the plurality of first electric wires being
bundled and twisted, the first end face being located at a distal end of the first end
portion; a second electric wire bundle including a plurality of second electric wires, the
10 second electric wire bundle having a second end portion wound helically around the
first end portion of the first electric wire bundle; and an insulating material covering
the first end portion and the second end portion. The second end portion is wound
to cover an edge portion of the first end face of the first electric wire bundle. The
second electric wire bundle has a second end face at an end of the second end
15 portion. The second end face of the second electric wire bundle is located to extend
from a circular outline of an outer peripheral surface of the second end portion or from
a region located inward from the circular outline.
[0007]
A compressor according to another embodiment of the present disclosure
20 includes: the above electric motor for a compressor; a compression element
configured to be driven by the electric motor to compress fluid sucked from outside;
and a hermetic container housing the electric motor and the compression element.
[0008]
A refrigeration cycle apparatus according to a further embodiment of the
25 present disclosure includes the above compressor, an outdoor heat exchanger, an
expansion valve, and an indoor heat exchanger.
[0009]
A method for manufacturing an electric motor for a compressor according to
still another embodiment of the present disclosure is a method for manufacturing an
30 electric motor for a compressor, which includes a stator including a stator winding.
5
The stator winding includes: a first electric wire bundle having a first end portion and a
first end face, the first end portion including end portions of a plurality of first electric
wires and being formed in the shape of a wire bundle, the end portions of the plurality
of first electric wires being bundled and twisted, the first end face being located at a
5 distal end of the first end portion; a second electric wire bundle including a plurality of
second electric wires and having a second end portion wound helically around the
first end portion of the first electric wire bundle; and an insulating material covering
the first end portion and the second end portion. The method includes: pressuring
the second end portion by applying a pressure to an outer peripheral surface of the
10 second end portion from outside, in a state in which the second end portion is wound
to cover an edge portion of the first end face of the first electric wire bundle and a
second end face at an end of the second end portion is located to extend from a
circular outline of the outer peripheral surface of the second end portion or from a
region inward of the circular outline.
15 Advantageous Effects of Invention
[0010]
According to the embodiments of the present disclosure, the second end
portion is wound around the first end portion including the first end face, where
projections are easily formed, such that the second end portion covers the edge
20 portion of the first end surface. The second end surface, where projections are
easily formed, is located to extend from the circular outline of the outer peripheral
surface of the second end portion or from a region inward of the circular outline.
This configuration reduces the probability that the projections will penetrate the
insulating material in the joint portion between the first and second end portions, and
25 thus reduces the occurrence of an insulation failure.
Brief Description of Drawings
[0011]
[Fig. 1] Fig. 1 is a circuit diagram of a refrigerant circuit in a cooling operation of
a refrigeration cycle apparatus according to Embodiment 1.
6
[Fig. 2] Fig. 2 is a circuit diagram of the refrigerant circuit in a heating operation
of the refrigeration cycle apparatus according to Embodiment 1.
[Fig. 3] Fig. 3 is a vertical sectional view illustrating a configuration of a
compressor as illustrated in Fig. 1.
5 [Fig. 4] Fig. 4 is a schematic plan view illustrating a configuration of a stator of
an electric motor as illustrated in Fig. 3.
[Fig. 5] Fig. 5 is a schematic layout illustrating a stator winding included in the
stator of the electric motor as illustrated in Fig. 3.
[Fig. 6] Fig. 6 is a connecting diagram of the stator winding as illustrated in Fig.
10 5.
[Fig. 7] Fig. 7 illustrates the other end portion of the stator winding as illustrated
in Fig. 5, which is covered by an insulating material, as viewed from an outer
peripheral surface side.
[Fig. 8] Fig. 8 illustrates only a second end portion as viewed from a distal end
15 side of a joint portion as illustrated in Fig. 7.
[Fig. 9] Fig. 9 illustrates only a second end portion as viewed from a distal end
side of a joint portion of a stator winding included in an electric motor according to
Embodiment 2.
[Fig. 10] Fig. 10 illustrates the other end portion of a stator winding included in
20 an electric motor according to Embodiment 3, which is covered by an insulating
material, as viewed from an outer peripheral surface side.
Description of Embodiments
[0012]
Embodiment 1
25 Fig. 1 is a circuit diagram of a refrigerant circuit 11 in a cooling operation in a
refrigeration cycle apparatus 10 according to Embodiment 1. Fig. 2 is a circuit
diagram of the refrigerant circuit 11 in a heating operation in the refrigeration cycle
apparatus 10 according to Embodiment 1. In Fig. 1, solid arrows indicate the flow
direction of refrigerant in the cooling operation. In Fig. 2, dashed arrows indicate
30 flow direction of the refrigerant in the heating operation.
7
[0013]
A configuration of the refrigeration cycle apparatus 10 will be described with
reference to Figs. 1 and 2. The refrigeration cycle apparatus 10 includes the
refrigerant circuit 11 in which the refrigerant is circulated. Embodiment 1 will be
5 described with respect to the case where the refrigeration cycle apparatus 10 is an
air-conditioning apparatus. However, the refrigeration cycle apparatus 10 may be an
apparatus other than the air-conditioning apparatus, such as a heat pump cycle
apparatus.
[0014]
10 In the refrigerant circuit 11, a compressor 12, an outdoor heat exchanger 14, a
pressure reducing device 15, an indoor heat exchanger 16, etc., are connected by
refrigerant pipes. The compressor 12 compresses the refrigerant and circulates the
refrigerant in the refrigerant circuit 11. The outdoor heat exchanger 14 and the
indoor heat exchanger 16 cause heat exchange to be performed between the
15 refrigerant and air. The pressure reducing device 15 is, for example, an expansion
valve, and expands the refrigerant to reduce the pressure of the refrigerant.
[0015]
In an example illustrated in Figs. 1 and 2, the refrigerant circuit 11 also includes
a flow switching device 13. The flow switching device 13 switches the flow passage
20 for refrigerant discharged from the compressor 12 between a plurality of flow
passages. The flow switching device 13 is, for example, a four-way valve.
[0016]
The flow switching device 13 switches the operation between the cooling
operation and the heating operation. The refrigeration cycle apparatus 10 includes a
25 controller 17 that controls various actuators. The controller 17 is, for example, a
microcomputer that includes a central processing unit (CPU) and a memory. More
specifically, the controller 17 controls, for example, the frequency of the compressor
12, the opening degree of the pressure reducing device 15, and a switching operation
of the flow switching device 13. As illustrated in Fig. 1, in the cooling operation, the
30 refrigerant discharged from the compressor 12 flows through the outdoor heat
8
exchanger 14, the pressure reducing device 15, and the indoor heat exchanger 16 in
this order, and returns to the compressor 12. As illustrated in Fig. 2, in the heating
operation, the refrigerant discharged from the compressor 12 flows through the indoor
heat exchanger 16, the pressure reducing device 15, and the outdoor heat exchanger
5 14 in that order, and returns to the compressor 12. That is, in the cooling operation
in an indoor space, the outdoor heat exchanger 14 operates as a condenser, and the
indoor heat exchanger 16 operates as an evaporator. In the heating operation in the
indoor space, the indoor heat exchanger 16 operates as a condenser, and the
outdoor heat exchanger 14 operates as an evaporator. Therefore, the indoor heat
10 exchanger 16 causes in the heating operation, the refrigerant compressed by the
compressor 12 to transfer heat such that air in the indoor space is heated, and
causes in the cooling operation, the refrigerant expanded by the pressure reducing
device 15 to receive heat such that air in the indoor space is cooled.
[0017]
15 As the refrigerant circulated in the refrigerant circuit 11, hydrofluorocarbon
(HFC)-based refrigerant, such as R32, R125, R134a, R407C, or R410A, is used, or
hydrofluoroolefin (HFO)-based refrigerant, such as R1123, R1132(E), R1132(Z),
R1132a, R1141, R1234yf, R1234ze(E), or R1234ze(Z), is used, or natural refrigerant,
such as R290 (propane), R600a (isobutane), R744 (carbon dioxide), or R717
20 (ammonia), is used. Other kinds of refrigerant may also be used. Alternatively, a
mixture of two or more of the above kinds of refrigerant may be used.
[0018]
The configuration of the refrigerant circuit 11 is not limited to the abovementioned configuration. For example, the flow switching device 13 may be omitted.
25 [0019]
Fig. 3 is a vertical sectional view illustrating the configuration of the compressor
12 as illustrated in Fig. 1. The configuration of the compressor 12 will be described
with reference to Fig. 3 on the assumption that that the compressor 12 is a singlecylinder hermetic rotary compressor. It should be noted that the present disclosure
9
can also be applied to the case where the compressor 12 is a multiple-cylinder rotary
compressor or a scroll compressor.
[0020]
As illustrated in Fig. 3, the compressor 12 includes a hermetic container 20, a
5 compression element 30, an electric motor 40 (electric motor for a compressor), and
a crankshaft 50. The hermetic container 20 includes an upper lid 20a, a tubular
body 20c, and a lower lid 20b that are joined together. A suction pipe 21 through
which the refrigerant is sucked is attached to the tubular body 20c. A discharge pipe
22 through which the refrigerant is discharged is attached to the upper lid 20a. The
10 discharge pipe 22 is attached to the top of the hermetic container 20, that is, to an
upper surface of the upper lid 20a, and both ends of the discharge pipe 22 in an axial
direction (direction indicated by an arrow Z) are open.
[0021]
The compression element 30 and the electric motor 40 are provided in the
15 hermetic container 20. The compression element 30 compresses the refrigerant
sucked through the suction pipe 21 and discharges the compressed refrigerant. The
electric motor 40 drives the compression element 30. In the example illustrated in
Fig. 3, the compression element 30 is provided in a lower region in the hermetic
container 20, and the electric motor 40 is provided above the compression element
20 30. Gas refrigerant discharged from the compression element 30 is released into a
hermetic space in the hermetic container 20 to fill the hermetic space, and then let out
to the refrigerant circuit 11 (for example, a condenser), which is located outside the
hermetic container 20, through the discharge pipe 22 provided in the upper lid 20a of
the hermetic container 20. The electric motor 40 may be provided in the hermetic
25 container 20 at any location at which the refrigerant compressed by the compression
element 30 passes through the electric motor 40 before being discharged through the
discharge pipe 22.
[0022]
Refrigerating machine oil 25 for lubrication of sliding portions of the
30 compression element 30 is stored at the bottom of the hermetic container 20. As the
10
refrigerating machine oil 25, one of polyol ester (POE), polyvinyl ether (PVE), and
alkylbenzene (AB), which are synthetic oils, is used.
[0023]
A terminal unit 24, which is connected to an external power supply (not
5 illustrated), is attached to the top of the hermetic container 20, that is, to the upper
surface of the upper lid 20a. The terminal unit 24 includes a plurality of terminals
24a each of which is, for example, a glass terminal. The terminal unit 24 is fixed to
the hermetic container 20 by, for example, welding. Leads 45 which extend from the
electric motor 40 provided in the hermetic container 20 are connected to the terminals
10 24a. The leads 45 are fixed to the terminals 24a which are, for example, the glass
terminals, and are insulated from the hermetic container 20.
[0024]
The compression element 30 will be described in detail with reference to Fig. 3.
The compression element 30 includes a cylinder 31, a rolling piston 32, a vane (not
15 illustrated), a main bearing 33, and an auxiliary bearing 34. The cylinder 31 is
attached to the inner periphery of the tubular body 20c of the hermetic container 20.
[0025]
The cylinder 31 is formed of a flat plate. The outer periphery of the cylinder 31
has a substantially circular shape as viewed in plan view. The cylinder 31 has a
20 cylinder chamber 31a formed therein. The cylinder chamber 31a is a space having a
substantially circular shape as viewed in plan view. Both ends of the cylinder
chamber 31a of the cylinder 31 in the axial direction (direction indicated by arrow Z)
are open. The rolling piston 32 is provided in the cylinder chamber 31a.
[0026]
25 The cylinder 31 has a vane groove (not illustrated) that communicates with the
cylinder chamber 31a and extends in a radial direction. In the cylinder 31, a back
pressure chamber is provided in a region located outward of the vane groove in the
radial direction. The back pressure chamber communicates with the vane groove
and has a substantially circular shape as viewed in plan view.
30 [0027]
11
The cylinder 31 has a suction port (not illustrated) through which gas refrigerant
is sucked from the refrigerant circuit 11 (for example, an evaporator). The suction
port extends through the cylinder 31 from the outer peripheral surface of the cylinder
31 to the cylinder chamber 31a. The cylinder 31 also has a discharge port (not
5 illustrated) through which the compressed refrigerant is discharged from the cylinder
chamber 31a. The discharge port is formed by cutting the upper end surface of the
cylinder 31.
[0028]
The rolling piston 32 is ring-shaped. The rolling piston 32 is slidably fitted to
10 an eccentric shaft portion 51 of the crankshaft 50, and eccentrically rotates in the
cylinder chamber 31a. When a rolling piston 9 eccentrically rotates in the cylinder
chamber 31a, the eccentric shaft portion 51 of the crankshaft 50 also eccentrically
rotates in the cylinder chamber 31a.
[0029]
15 The vane is formed in the shape of a substantially flat cuboid. The vane is
provided in the vane groove in the cylinder 31. The vane is constantly pushed
against the rolling piston 32 by a vane spring (not illustrated) provided in the back
pressure chamber. Since the pressure in the hermetic container 20 is high, when
the compressor 12 starts to operate, a force generated by a pressure difference
20 between the hermetic container 20 and the cylinder chamber 31a acts on a back
surface (that is, a surface adjacent to the back pressure chamber) of the vane.
When no pressure difference is made between the hermetic container 20 and the
cylinder chamber 31a as at the time of activating the compressor 12, the vane is
pushed against the rolling piston 32 by the vane spring. Thus, the cylinder chamber
25 31a is partitioned into a low-pressure suction chamber and a high-pressure
compression chamber.
[0030]
The main bearing 33 is substantially inverted T-shaped as viewed side-on.
The main bearing 33 is slidably fitted to a main shaft portion 52 that is a portion of the
30 crankshaft 50 that is located above the eccentric shaft portion 51. The main bearing
12
33 closes the cylinder chamber 31a of the cylinder 31 and an upper side of the vane
groove. The auxiliary bearing 34 is substantially inverted T-shaped as viewed sideon. The auxiliary bearing 34 is slidably fitted to an auxiliary shaft portion 53 that is a
portion of the crankshaft 50 that is located below the eccentric shaft portion 51. The
5 auxiliary bearing 34 closes the cylinder chamber 31a of the cylinder 31 and a lower
side of the vane groove.
[0031]
The main bearing 33 has a discharge opening (not illustrated). The discharge
port of the cylinder 31 communicates with the discharge opening of the main bearing
10 33. At the discharge opening, a discharge valve (not illustrated) is provided. The
discharge valve is opened when the pressure in a cylinder chamber 13a reaches or
exceeds a predetermined pressure. A discharge muffler 35 is attached to the main
bearing 33 in such a manner as to cover the discharge valve. High-temperature and
high-pressure gas refrigerant discharged through the discharge valve enters the
15 discharge muffler 35, and is then released from the discharge muffler 35 into the
space in the hermetic container 20. The discharge valve and the discharge muffler
35 may be provided at the auxiliary bearing 34 or at both the main bearing 33 and the
auxiliary bearing 34.
[0032]
20 The material of the cylinder 31, the main bearing 33, and the auxiliary bearing
34 is, for example, gray iron, sintered steel, or carbon steel. The material of the
rolling piston 32 is, for example, alloy steel containing, for example, chromium. The
material of the vane is, for example, high-speed tool steel.
[0033]
25 A suction muffler 23 is provided adjacent to the hermetic container 20. Lowpressure gas refrigerant is sucked from the refrigerant circuit 11 (for example, an
evaporator) into the suction muffler 23. The suction muffler 23 reduces the
probability that liquid refrigerant will directly enter the cylinder chamber 31a of the
cylinder 31 in the case where the liquid refrigerant returns to the compressor 12.
30 The suction muffler 23 is connected to the suction port of the cylinder 31 by the
13
suction pipe 21. A main body of the suction muffler 23 is fixed to a side surface of
the hermetic container 20 by, for example, welding.
[0034]
Fig. 4 is a schematic plan view illustrating a configuration of a stator 41 of the
5 electric motor 40 as illustrated in Fig. 3. Fig. 5 is a schematic layout illustrating a
stator winding 44 included in the stator 41 of the electric motor 40 as illustrated in Fig.
3. The electric motor 40 will be described in detail with reference to Figs. 3 to 5.
[0035]
Regarding Embodiment 1, it is assumed that the electric motor 40 is an
10 induction electric motor. The present disclosure can be applied also to the case
where the electric motor 40 is a motor other than an induction electric motor, for
example, a brushless direct current (DC) motor.
[0036]
As illustrated in Fig. 3, the electric motor 40 includes the stator 41 and a rotor
15 42. The stator 41 is substantially cylindrical, and is in contact with and fixed to an
inner peripheral surface of the hermetic container 20. The rotor 42 is cylindrical, and
is provided in the stator 41, with a gap of approximately 0.3 to 1 mm provided
between the rotor 42 and the stator 41.
[0037]
20 The stator 41 includes a stator core 43 and a stator winding 44. The stator
core 43 is formed of a plurality of magnetic steel sheets. More specifically, a plurality
of magnetic steel sheets having a thickness of 0.1 to 1.5 mm are subjected to
punching processing to have a predetermined shape, are stacked together in an axial
direction (direction indicated by arrow Z), and are fixed together by, for example,
25 crimping or welding, thereby forming the stator core 43.
[0038]
As illustrated in Fig. 4, the stator core 43 has a plurality of cuts 43b formed in
the outer periphery thereof such that the cuts 43b are arranged at substantially
regular intervals in a circumferential direction. As illustrated in Figs. 3 and 4, a
30 space is provided between each of the cuts 43b and the inner surface of the tubular
14
body 20c of the hermetic container 20. This space serves as a passage toward the
discharge pipe 22 for the gas refrigerant released from the discharge muffler 35 into
the space in the hermetic container 20. Each cut 43b also serves as a passage for
the refrigerating machine oil 25 which returns from a region above the electric motor
5 40 to the bottom of the hermetic container 20.
[0039]
As illustrated in Fig. 5, the stator core 43 includes a yoke 43y having a
cylindrical shape and teeth 43t that extend toward a rotational axis Ax from an inner
peripheral surface of the yoke 43y. The teeth 43t are arranged at regular intervals in
10 the circumferential direction (direction indicated by arrow R). Between any adjacent
two of the teeth 43t, a slot 43a is provided.
[0040]
The stator winding 44 includes winding wires wound around the teeth 43t of the
stator core 43, and are partially provided in the slots 43a. The leads 45 are
15 connected to the stator winding 44, and the stator winding 44 is connected to the
terminals 24a by the leads 45.
[0041]
In the example illustrated in Fig. 4, the electric motor 40 is a three-phase
electric motor that is supplied with electric power from an external three-phase power
20 supply. Three leads 45 are joined to the stator winding 44. In the example
illustrated in Fig. 3, the terminal unit 24 provided at the hermetic container 20 includes
three terminals 24a associated with the V-phase, the W-phase, and the U-phase of
the three phase power supply. Each of the three leads 45 connects an associated
winding portion of the stator winding 44 to an associated one of the terminals 24a.
25 [0042]
In Fig. 5, the three leads 45 are distinguished from each other and denoted by
different reference signs. In the following description, of these leads, a lead
connected to the terminal 24a associated with the V-phase of the three phase power
supply may be referred to as a V-phase lead 45v, a lead connected to the terminal
30 24a associated with the W-phase may be referred to as a W-phase lead 45w, and a
15
lead connected to the terminal 24a associated with the U-phase may be referred to as
a U-phase lead 45u.
[0043]
When the stator winding 44 of the stator 41 is energized, a plurality of magnetic
5 poles that rotate in the circumferential direction of the yoke 43y are produced at the
teeth 43t, and as a result, a rotating magnetic field is produced.
[0044]
As illustrated in Fig. 3, the rotor 42 includes a substantially cylindrical rotor iron
core 46 that extends in the axial direction (direction indicated by arrow Z), rod-shaped
10 conductors 48 that extends in the axial direction, and annular end rings 47 that are
provided at both ends of the rotor iron core 46 in the axial direction and that shortcircuit the conductors 48. The rotor iron core 46 has a plurality of rotor slots 46a that
are formed in an outer peripheral portion thereof such that rotor slots 46a are
arranged in the circumferential direction (direction indicated by arrow R), and the
15 conductors 48 are provided in respective ones of the rotor slots 46a.
[0045]
The rotor iron core 46 is formed of a plurality of magnetic steel sheets. More
specifically, the rotor iron core 46, as well as the stator core 43, is formed in the
following manner: a plurality of magnetic steel sheets having a thickness of 0.1 to 1.5
20 mm are subjected to punching processing in such a manner as to have a
predetermined shape; they are stacked together in the axial direction; and they are
fixed together by, for example, crimping or welding.
[0046]
The conductors 48 are made of a conductive substance, such as aluminum.
25 The conductors 48 may be made of, for example, copper. The conductors 48 are
filled or inserted into respective ones of the rotor slots 46a formed in the rotor iron
core 46 and arranged in the circumferential direction. The end rings 47 short-circuit
both ends of each of the conductors 48 in the axial direction.
[0047]
16
The rotor iron core 46 has a plurality of through holes (not illustrated) that
extend therethrough substantially in the axial direction. The through holes, as well
as the cuts 43b (see Fig. 4) in the stator core 43, serve as passages toward the
discharge pipe 22 for the gas refrigerant released from the discharge muffler 35 into
5 the space in the hermetic container 20.
[0048]
The rotor 42 is, for example, a squirrel-cage rotor formed by an aluminum die
casting. The aluminum die casting is a casting method in which a molten metal,
such as an aluminum alloy, is filled into a mold at a high speed and cast under a high
10 pressure. By using this casting method, high-precision castings with good casting
surfaces can be produced. More specifically, the squirrel-cage rotor is formed by
casting and shaping a conductive substance, such as aluminum, in the rotor slots 46a
by, for example, die casting. The configuration of the rotor 42 is not limited to the
above-mentioned configuration.
15 [0049]
In the above induction electric motor, the rotor 42 is rotated about the rotational
axis Ax by a force that is generated because of interaction between current induced in
the conductors 48 of the rotor 42 from the stator winding 44 included in the stator 41
and a rotating magnetic field produced at the stator 41.
20 [0050]
In the case where the electric motor 40 is a brushless DC motor (not
illustrated), permanent magnets are inserted in the rotor slots 46a in the rotor iron
core 46 instead of the conductors 48. The permanent magnets are, for example,
ferrite magnets or rare-earth magnets. In addition, in the case where the electric
25 motor 40 is a brushless DC motor, an upper end plate and a lower end plate are
provided at the ends of the rotor iron core 46 in the axial direction instead of the end
rings 47 to prevent the permanent magnets from being pulled out in the axial direction
(direction indicated by arrow Z). The upper end plate and the lower end plate are
fixed to the rotor iron core 46 by, for example, a plurality of fixing rivets. The upper
30 end plate and the lower end plate are made of non-magnetic material, and prevent
17
falling of the permanent magnets and occurrence of flux leakage. The upper end
plate and the lower end plate double as rotation balancers. In such a brushless DC
motor, the rotor 42 is rotated about the rotational axis Ax, when currents are made to
flow through the stator winding 44 such that magnetic fields produced by the
5 permanent magnets in the rotor 42 are orthogonal to a magnetic field produced by the
stator winding 44.
[0051]
The operation of the compressor 12 will be described with reference to Fig. 3.
The stator 41 of the electric motor 40 is supplied with electric power from the
10 terminals 24a of the terminal unit 24 through the leads 45. As a result, the rotor 42 is
rotated by the above operation of the electric motor 40. When the rotor 42 is rotated,
the crankshaft 50 fixed to the rotor 42 is also rotated. When the crankshaft 50 is
rotated, the rolling piston 32 of the compression element 30 is eccentrically rotated in
the cylinder chamber 31a of the cylinder 31. The space between the cylinder 31 and
15 the rolling piston 32 is partitioned into two spaces by the vane of the compression
element 30, and the volumes of the two spaces vary as the crankshaft 50 rotates.
When the volume of one of the two spaces gradually increases, the refrigerant is
sucked into this space from the suction muffler 23. When the volume of the other of
the two spaces gradually decreases, gas refrigerant in this space is compressed.
20 The compressed gas refrigerant is discharged from the discharge muffler 35 into the
hermetic space in the hermetic container 20. The discharged gas refrigerant flows
through the electric motor 40 and is discharged to the outside of the hermetic
container 20 through the discharge pipe 22 located at the top of the hermetic
container 20. Wire connecting and junction portions of the stator winding 44 and the
25 leads 45 are provided in the hermetic space in the hermetic container 20. These
portions are covered by an insulating material, but are exposed to the gas refrigerant.
[0052]
Fig. 6 is a connecting diagram of the stator winding 44 as illustrated in Fig. 5.
The following description concerning the configuration of the stator winding 44 is
30 made with reference to Figs. 5 and 6 by referring to by way of example the case
18
where the electric motor 40 is a three-phase electric motor and the stator winding 44
is an assembly of three independent winding portions.
[0053]
As illustrated in Fig. 5, the stator winding 44 includes a U-phase winding
5 portion 61, a V-phase winding portion 62, and a W-phase winding portion 63. One
end of the U-phase winding portion 61 is connected to the U-phase lead 45u by, for
example, joining material. Similarly, one end of the V-phase winding portion 62 is
connected to the V-phase lead 45v, and one end of the W-phase winding portion 63 is
connected to the W-phase lead 45w. A joint portion 61a between the one end of the
10 U-phase winding portion 61 and the U-phase lead 45u, a joint portion 62a between
the one end of the V-phase winding portion 62 and the V-phase lead 45v, and a joint
portion 63a between the one end of the W-phase winding portion 63 and the W-phase
lead 45w are provided in a region in the stator 41 that is adjacent to the terminal unit
24, that is, an upper region in the stator 41.
15 [0054]
It should be noted that a wiring board for terminal processing may be provided
at an upper end of the stator 41, and the winding portions of the stator winding 44
may be joined to the leads 45 on the wiring board.
[0055]
20 The other ends of the U-phase winding portion 61, the V-phase winding portion
62, and the W-phase winding portion 63 are joined together to form a joint portion 70.
In the joint portion 70, the U-phase winding portion 61, the V-phase winding portion
62, and the W-phase winding portion 63 are electrically connected to each other.
The joint portion 70 serves as a neutral point 70a (see Fig. 6) at which the voltage is
25 zero at all times.
[0056]
An insulating material 71 that covers the joint portion 70 is provided at the other
end portion 44a of the stator winding 44 which includes the joint portion 70. The joint
portion 70 covered by the insulating material 71 is embedded and thus fixed between
30 the winding wires of the stator winding 44. An intermediate portion between one end
19
and the other end of each of the U-phase winding portion 61, the V-phase winding
portion 62, and the W-phase winding portion 63 is wound around the teeth 43t of the
stator 41 and provided in the slots 43a or other regions.
[0057]
5 As illustrated in Fig. 6, each of the U-phase winding portion 61, the V-phase
winding portion 62, and the W-phase winding portion 63 includes two electric winding
wires that are a copper wire and an aluminum wire. More specifically, the U-phase
winding portion 61 includes a U-phase copper wire 64 and a U-phase aluminum wire
65. Similarly, the V-phase winding portion 62 includes a V-phase copper wire 66 and
10 a V-phase aluminum wire 67, and the W-phase winding portion 63 includes a Wphase copper wire 68 and a W-phase aluminum wire 69. The configuration of each
winding portion is not particularly limited to the above configuration. For example,
each of the winding portions may include two electric winding wires that are both
copper wires or both aluminum wires.
15 [0058]
Each of the U-phase copper wire 64, the U-phase aluminum wire 65, the Vphase copper wire 66, the V-phase aluminum wire 67, the W-phase copper wire 68,
and the W-phase aluminum wire 69 includes four coils. More specifically, the Uphase copper wire 64 includes four U-phase copper wire coils 64a to 64d connected
20 in series, and the U-phase aluminum wire 65 includes four U-phase aluminum wire
coils 65a to 65d connected in series. Similarly, the V-phase copper wire 66 includes
four V-phase copper wire coils 66a to 66d connected in series, and the V-phase
aluminum wire 67 includes four V-phase aluminum wire coils 67a to 67d connected in
series. Similarly, the W-phase copper wire 68 includes four W-phase copper wire
25 coils 68a to 68d connected in series, and the W-phase aluminum wire 69 includes
four W-phase aluminum wire coils 69a to 69d connected in series.
[0059]
At the other end of the U-phase winding portion 61, a terminal portion of the Uphase copper wire 64 and a terminal portion of the U-phase aluminum wire 65 are
30 connected to the neutral point 70a. Similarly, at the other end of the V-phase
20
winding portion 62, a terminal portion of the V-phase copper wire 66 and a terminal
portion of the V-phase aluminum wire 67 are connected to the neutral point 70a.
Similarly, at the other end of the W-phase winding portion 63, a terminal portion of the
W-phase copper wire 68 and a terminal portion of the W-phase aluminum wire 69 are
5 connected to the neutral point 70a.
[0060]
The terminal portion of the U-phase copper wire 64 is a terminal portion of the
U-phase copper wire coil 64d, and the terminal portion of the U-phase aluminum wire
65 is a terminal portion of the U-phase aluminum wire coil 65d. Similarly, the
10 terminal portion of the V-phase copper wire 66 is a terminal portion of a V-phase
copper wire coil 66d, and the terminal portion of the V-phase aluminum wire 67 is a
terminal portion of a V-phase aluminum wire coil 67d. Similarly, the terminal portion
of the W-phase copper wire 68 is a terminal portion of a W-phase copper wire coil
68d, and the terminal portion of the W-phase aluminum wire 69 is a terminal portion of
15 a W-phase aluminum wire coil 69d.
[0061]
Thus, the terminal portions of the three copper winding wires, which are the Uphase copper wire 64, the V-phase copper wire 66, and the W-phase copper wire 68,
and the terminal portions of the three aluminum winding wires, which are the U-phase
20 aluminum wire 65, the V-phase aluminum wire 67, and the W-phase aluminum wire
69, are collected together in a single region to form the joint portion 70.
[0062]
In the following description, the terminal portion of the U-phase copper wire 64
may be referred to as a U-phase copper wire terminal portion 64e, and the terminal
25 portion of the U-phase aluminum wire 65 may be referred to as a U-phase aluminum
wire terminal portion 65e. Similarly, the terminal portion of the V-phase copper wire
66 may be referred to as a V-phase copper wire terminal portion 66e, and the terminal
portion of the V-phase aluminum wire 67 may be referred to as a V-phase aluminum
wire terminal portion 67e. Similarly, the terminal portion of the W-phase copper wire
30 68 may be referred to as a W-phase copper wire terminal portion 68e, and the
21
terminal portion of the W-phase aluminum wire 69 may be referred to as a W-phase
aluminum wire terminal portion 69e.
[0063]
As illustrated in Fig. 5, the U-phase copper wire terminal portion 64e and the U5 phase aluminum wire terminal portion 65e extend from the same slot 43a in the stator
41. Similarly, the V-phase copper wire terminal portion 66e and the V-phase
aluminum wire terminal portion 67e extend from a slot 43a that is other than the slot
43a in which the U-phase copper wire terminal portion 64e is provided. Similarly, the
W-phase copper wire terminal portion 68e and the W-phase aluminum wire terminal
10 portion 69e extend from a slot 43a that is other than the slot 43a in which the U-phase
copper wire terminal portion 64e is provided and the slot 43a in which the V-phase
copper wire terminal portion 66e is provided. The terminal portions extending from
the slots 43a are bundled together by the insulating material 71 in a certain region
including the joint portion 70 to form the other end portion 44a of the stator winding
15 44.
[0064]
The insulating material 71 is, for example, insulating paper. The insulating
material 71 is an insulating substance, for example, polyethylene terephthalate (PET).
The insulating material 71 joins parts of the U-phase copper wire terminal portion 64e,
20 the U-phase aluminum wire terminal portion 65e, the V-phase copper wire terminal
portion 66e, the V-phase aluminum wire terminal portion 67e, the W-phase copper
wire terminal portion 68e, and the W-phase aluminum wire terminal portion 69e, and
insulates the neutral point 70a (Fig. 6), the above parts of these wire terminal portions
being located adjacent to the joint portion 70. The insulating material 71 covers an
25 outer peripheral surface and an end surface of the other end portion 44a of the stator
winding 44.
[0065]
The configuration of the insulating material 71 is not limited to the abovementioned configuration. For example, as the insulating material 71 that insulates
30 the neutral point 70a, an elastic insulating tube may be used instead of the insulating
22
paper. In this case, the insulating tube can be brought into close contact with the
joint portion 70 by utilizing elastic expansion and contraction of the insulating tube.
Therefore, it is not necessary to perform a process of contracting the insulating
material 71 by, for example, applying a pressure to the insulating material 71 from the
5 outside, and the insulating material 71 can thus be more efficiently produced.
[0066]
Fig. 7 illustrates the other end portion 44a of the stator winding 44 as illustrated
in Fig. 5, which is covered by the insulating material 71, as viewed from the outer
peripheral surface side. Fig. 8 illustrates only a second end portion 91 as viewed
10 from a distal end side of the joint portion 70 as illustrated in Fig. 7. The configuration
of the other end portion 44a of the stator winding 44 which includes the joint portion
70 will be described with reference to Figs. 7 and 8.
[0067]
As illustrated in Fig. 7, the terminal portions of the three copper winding wires,
15 that is, the U-phase copper wire terminal portion 64e, the V-phase copper wire
terminal portion 66e, and the W-phase copper wire terminal portion 68e, are bundled
and twisted to form a first electric wire bundle 80. The terminal portions of the three
aluminum winding wires, that is, the U-phase aluminum wire terminal portion 65e, the
V-phase aluminum wire terminal portion 67e, and the W-phase aluminum wire
20 terminal portion 69e, form a second electric wire bundle 90.
[0068]
In the following description, each of the U-phase copper wire terminal portion
64e, the V-phase copper wire terminal portion 66e, and the W-phase copper wire
terminal portion 68e that form the first electric wire bundle 80 may be referred to as a
25 first electric wire. Each of the U-phase aluminum wire terminal portion 65e, the Vphase aluminum wire terminal portion 67e, and the W-phase aluminum wire terminal
portion 69e that form the second electric wire bundle 90 may be referred to as a
second electric wire.
[0069]
23
The first electric wire bundle 80 includes a first end portion 81 that is formed in
the shape of a wire bundle and adjacent to the joint portion 70. The first end portion
81 has a first end face 82a at its distal end. The first end face 82a of the first electric
wire bundle 80 is, for example, a cut surface formed by applying a force to the first
5 electric wire bundle 80 in an up-down direction. The first end face 82a collapses in
the up-down direction when a force is applied to first end face 82a to cut the first
electric wires, and is thus wider than the vicinity of the distal end.
[0070]
The second electric wire bundle 90 includes a second end portion 91 that is
10 helically wound around the first end portion 81 of the first electric wire bundle 80.
The second end portion 91 has a second end face 92a (see Fig. 8) at its distal end.
The second end portion 91 of the second electric wire bundle 90 is wound around the
first end portion 81 to cover an edge portion of the first end face 82a of the first
electric wire bundle 80. Thus, as illustrated in Fig. 7, the second end portion 91 is
15 located on a distal end side of the other end portion 44a of the stator winding 44.
[0071]
In the example illustrated in Fig. 7, the U-phase aluminum wire terminal portion
65e, the V-phase aluminum wire terminal portion 67e, and the W-phase aluminum
wire terminal portion 69e which form the second electric wire bundle 90 are provided
20 adjacent to each other while being in contact with the outer peripheral surface of the
first end portion 81. The second end portion 91 includes a first helical portion 91a
that is adjacent to a distal end portion 92 of the second end portion 91 and a second
helical portion 91b that is wound subsequently from the first helical portion 91a. A
gap G at which part of the outer peripheral surface of the first end portion 81 is
25 exposed is provided between the first helical portion 91a and the second helical
portion 91b.
[0072]
A joining material 75 is provided in such a manner as to cover the first end
portion 81 and the second end portion 91, with the second end portion 91 wound
30 around the first end portion 81, whereby the first end portion 81 and the second end
24
portion 91 are joined together. The joining material 75 is also provided in the gap G.
In addition, the insulating material 71 is provided in such a manner as to cover the
joint portion 70 of the first end portion 81 and the second end portion 91, and also in
such a manner as to cover the outer peripheral surface and the distal end face of the
5 other end portion 44a of the stator winding 44.
[0073]
As described above, the second end portion 91 of the second electric wire
bundle 90 is helically wound around the first end portion 81 in such a manner as to
cover the edge portion of the first end face 82a of the first electric wire bundle 80.
10 Therefore, it is possible to reduce the probability that when the insulating material 71
is wound, projections on the edge portion of the first end face 82a, which is the cut
surface, will penetrate the insulating material 71, and it is also possible to reduce
occurrence of an insulation failure.
[0074]
15 In particular, in the case where a paper-like material, such as insulating paper,
is wound around the outer peripheral surface of the joint portion 70, thereby forming
the insulating material 71, the insulating material 71 is pressed against the outer
peripheral surface of the joint portion 70. Thus, in the case where the edge portion
of the first end face 82a has projections, the insulating material 71 are easily torn. In
20 the present embodiment, the second end portion 91 which has a helical shape is
provided such that the edge portion of the first end face 82a is not brought into direct
contact with the insulating material 71. Thus, in a manufacturing process in which
the joint portion 70 is covered with a paper-shaped insulating material 71, the above
configuration reduces the probability that the insulating material 71 will be torn by the
25 projections.
[0075]
In addition, as illustrated in Fig. 8, as the joint portion 70 is viewed from the
distal end face side of the other end portion 44a of the stator winding 44, the second
end portion 91 has an outer peripheral surface 93 having a circular outline. The
30 second end face 92a at the distal end of the second end portion 91 is located to
25
extend from the circular outline of the outer peripheral surface 93 of the second end
portion 91 or from a region located inward of the circular outline. In the example
illustrated in Fig. 8, the second end face 92a is a surface that extends from the
circular outline of the outer peripheral surface 93 toward a center C1 of the outer
5 peripheral surface 93.
[0076]
As described above, the second end portion 91 is formed such that the second
end face 92a is located to extend from the circular outline of the outer peripheral
surface 93 or from the region located inward of the circular outline thereof. This
10 configuration reduces, when the insulating material 71 is wound, the probability that
projections on an edge portion of the second end face 92a, which is the cut surface,
will penetrate the insulating material 71, and thus further reduce occurrence of an
insulation failure.
[0077]
15 As described above, the electric motor for a compressor (electric motor 40)
according to Embodiment 1 is the electric motor 40 which is provided with the stator
41 including the stator winding 44. The stator winding 44 includes the first electric
wire bundle 80 and the second electric wire bundle 90. The first electric wire bundle
80 includes the first end portion 81 that is formed in the shape of a wire bundle such
20 that end portions of the plurality of first electric wires are bundled and twisted. The
second electric wire bundle 90 includes the second end portion 91 including the
second electric wires and wound helically around the first end portion 81 of the first
electric wire bundle 80. The stator winding 44 also includes the insulating material
71 which cover the first end portion 81 and the second end portion 91. The first
25 electric wire bundle 80 has the first end face 82a at a distal end of the first end portion
81. The second end portion 91 is wound in such a manner as to cover the edge
portion of the first end face 82a of the first electric wire bundle 80. The second
electric wire bundle 90 has the second end face 92a at an distal end of the second
end portion 91. The second end face 92a is located to extend from the circular
26
outline of the outer peripheral surface 93 of the second end portion 91 or from the
region located inward of the circular outline thereof.
[0078]
Thus, the second end portion 91 is wound around the first end portion 81
5 including the first end face 82a, where projections are easily formed, such that the
second end portion 91 covers the edge portion of the first end face 82a. The second
end face 92a, where projections are easily formed, is located to extend from the
circular outline of the outer peripheral surface 93 of the second end portion 91 or from
the region located inward of the circular outline. This configuration reduces the
10 probability that the projections will penetrate the insulating material 71 in the joint
portion 70 of the first end portion 81 and the second end portion 91, and thus reduces
occurrence of an insulation failure.
[0079]
The compressor 12 according to Embodiment 1 includes the electric motor 40,
15 the compression element 30 which is driven by the electric motor 40 to compress fluid
sucked from the outside, and the hermetic container 20 which houses the electric
motor 40 and the compression element 30. By virtue of this configuration, it is
possible to provide a compressor 12 in which the occurrence of an insulation failure in
the electric motor 40 is reduced and which has a high reliability and high safety.
20 [0080]
Furthermore, the refrigeration cycle apparatus 10 according to Embodiment 1
includes the compressor 12, the outdoor heat exchanger 14, the pressure reducing
device 15, and the indoor heat exchanger 16. By virtue of this configuration, the
refrigeration cycle apparatus 10 reduces the occurrence of malfunctions in the
25 compressor 12 and has a high reliability and high safety.
[0081]
Embodiment 2
Fig. 9 illustrates only a second end portion 91 as viewed from a distal end side
of the joint portion 70 of the stator winding 44 included in an electric motor 40
30 according to Embodiment 2. In Embodiment 2, the shape of the distal end portion
27
92 of the second end portion 91 at the joint portion 70 (see Fig. 5) of the stator
winding 44 is different from that in Embodiment 1. The other configurations of
Embodiment 2 are similar to those in Embodiment 1. Regarding Embodiment 2,
components that are the same as those in Embodiment 1 will be denoted by the
5 same reference signs. The following description concerning Embodiment 2 is made
by referring mainly to the differences between Embodiments 1 and 2.
[0082]
As illustrated in Fig. 9, at the second end portion 91, the distal end portion 92
having the second end face 92a is bent inward from the circular outline of the outer
10 peripheral surface 93 of the second end portion 91, and the second end face 92a is
located inward of the circular outline of the outer peripheral surface 93 of the second
end portion 91. That is, in Embodiment 2, as the joint portion 70 is viewed from the
distal end face side of the other end portion 44a of the stator winding 44, the second
end face 92a of the second end portion 91 is located inward of and apart from the
15 circular outline of the outer peripheral surface 93 of the second end portion 91.
[0083]
As described above, in the electric motor for a compressor (electric motor 40)
according to Embodiment 2, the second end face 92a of the second electric wire
bundle 90 is located inward of the circular outline of the outer peripheral surface 93 of
20 the second end portion 91. Thus, when the insulating material 71 is wound around
the joint portion 70, the force that presses the insulating material 71 against the
second end face 92a, which is the cut surface, is reduced due to the outer peripheral
surface 93 located outward of the second end face 92a. This configuration further
reduces the probability that the projections on the edge portion of the second end
25 face 92a will penetrate the insulating material 71, and thus further reduces the
occurrence of an insulation failure than in Embodiment 1.
[0084]
Embodiment 3
Fig. 10 illustrates the other end portion 44a of the stator winding 44 included in
30 an electric motor 40 according to Embodiment 3 that is covered by an insulating
28
material 71, as viewed from an outer peripheral surface side. In Embodiment 3, in
the second end portion 91 at the joint portion 70 (see Fig. 5) of the stator winding 44,
the intervals between helical portions are different those in Embodiment 1. In
Embodiment 3, the other configurations are similar to those in Embodiment 1.
5 Regarding Embodiment 3, components that are the same as those in Embodiment 1
will be denoted by the same reference signs. The following description concerning
Embodiment 3 is made by referring mainly to the differences between Embodiments 1
and 3.
[0085]
10 As illustrated in Fig. 10, in the second end portion 91 that is helically wound
around the first end portion 81, crests 100 and roots 101 recessed from the crests
100 are alternately arranged. More specifically, in the second end portion 91, the
roots 101 have an outer diameter D2 less than an outer diameter D1 of the crests
100. In the second end portion 91, the terminal portions of the second end portion
15 91, that is, the U-phase aluminum wire terminal portion 65e, the V-phase aluminum
wire terminal portion 67e, and the W-phase aluminum wire terminal portion 69e, are
arranged, with no gap G (see Fig. 7) interposed therebetween.
[0086]
In the example illustrated in Fig. 10, the second end portion 91 includes a first
20 helical portion 91a and a second helical portion 91b that are arranged with no gap
such that the outer peripheral surface of the first end portion 81 is not exposed. The
first helical portion 91a and the second helical portion 91b both have the crests 100
and the roots 101. In the example illustrated in Fig. 10, in each of the helical
portions of the second end portion 91, the U-phase aluminum wire terminal portion
25 65e and the W-phase aluminum wire terminal portion 69e, between which the Vphase aluminum wire terminal portion 67e is provided, are recessed from the V-phase
aluminum wire terminal portion 67e. Although the second end portion 91 includes a
plurality of crests 100 and a plurality of roots 101 in the illustrated example, the
number of crests 100 and the number of roots 101 may be one or more.
30 [0087]
29
The joining material 75 is provided to cover all of the crests 100 and the roots
101 of the second end portion 91 wound around the first end portion 81, and the first
end portion 81 and the second end portion 91 are joined together. The insulating
material 71 is provided to cover the joint portion 70 of the first end portion 81 and the
5 second end portion 91.
[0088]
The other end portion 44a of the stator winding 44 described above can be
manufactured by, for example, the following manufacturing method. First, the
second end portion 91 is helically wound around the first end portion 81. At this
10 time, the second end portion 91 is wound to cover the edge portion of the first end
face 82a of the first electric wire bundle 80, and the second end face 92a at the distal
end of the second end portion 91 is provided to extend from the circular outline of the
outer peripheral surface 93 of the second end portion 91 or from the region located
inward of the circular outline. Then, the second end portion 91 is pressurized from
15 the outside, with the second end portion 91 wound around the first end portion 81.
More specifically, a pressure is applied to the outer peripheral surface 93 of the
second end portion 91 from the outside. At this time, the projections on the edge
portion of the second end face 92a are made to collapse by the pressure applied from
the outside. Also, at this time, the pressure applied to the outer peripheral surface of
20 the second end portion 91 varies in the direction in which the other end portion 44a
extends. Thus, the second end portion 91 is plastically deformed by the pressure
such that the crests 100 and the roots 101 are formed on the second end portion 91.
After that, the joining material 75 is applied to cover all of the crests 100 and the roots
101 on the second end portion 91. At this time, the applied joining material 75 easily
25 reaches the roots 101, which are recessed from the crests 100, on the outer
peripheral surface 93 of the second end portion 91. Accordingly, particularly at the
roots 101, the joining material 75 easily flows through the spaces between the
terminal portions and reaches the first end portion 81, whereby the first end portion 81
and the second end portion 91 can be satisfactorily joined together. After the first
30
end portion 81 and the second end portion 91 are joined together by the joining
material 75, the joint portion 70 is covered by the insulating material 71.
[0089]
As described above, the electric motor for a compressor (electric motor 40)
5 according to Embodiment 3 includes the joining material 75 that joins the first end
portion 81 and the second end portion 91 together. The second end portion 91
includes the crests 100 and the roots 101 arranged alternately in the direction in
which the first end portion 81 extends. The roots 101 are recessed from the crests
100 and have the outer diameter D2 less than the outer diameter D1 of the crests
10 100. The joining material 75 covers the crests 100 and the roots 101 of the second
end portion 91.
[0090]
Therefore, the joining material 75 easily reaches the roots 101, which are
recessed from the crests 100, on the outer peripheral surface 93 of the second end
15 portion 91. Thus, particularly at the roots 101, the joining material 75 easily flows
through the spaces between the second electric wires and reaches the first end
portion 81, whereby the first end portion 81 and the second end portion 91 can be
satisfactorily joined together.
[0091]
20 The method for manufacturing the electric motor for a compressor (electric
motor 40) according to Embodiment 3 is a method for manufacturing the electric
motor which is provided with the stator 41 including the stator winding 44. The stator
winding 44 includes the first electric wire bundle 80, the second electric wire bundle
90, and the insulating material 71. The first electric wire bundle 80 includes the first
25 end portion 81 which is formed in the shape of a wire bundle and in which end
portions of the plurality of first electric wires are bundled and twisted. The second
electric wire bundle 90 includes the second electric wires and has the second end
portion 91 wound helically around the first end portion 81 of the first electric wire
bundle 80. The insulating material 71 covers the first end portion 81 and the second
30 end portion 91. The first electric wire bundle 80 has the first end face 82a at a distal
31
end of the first end portion 81. In the method for manufacturing the electric motor
40, a pressure is applied to the outer peripheral surface 93 of the second end portion
91 from the outside, in a state in which the second end portion 91 is wound to cover
the edge portion of the first end face 82a of the first electric wire bundle 80 and the
5 second end face 92a at the distal end of the second end portion 91 is located to
extend from the circular outline of the outer peripheral surface 93 of the second end
portion 91 or from the region located inward of the circular outline.
[0092]
Thus, when the pressure is applied to the outer peripheral surface 93 of the
10 second end portion 91 from the outside, the projections on the edge portion of the
second end face 92a collapses. As a result, the insulating material 71 becomes
harder to tear at the edge portion of the second end face 92a, which is the cut
surface, and the occurrence of insulation failures can be further reduced.
[0093]
15 In the method for manufacturing the electric motor for a compressor (electric
motor 40), the pressure is applied to the outer peripheral surface 93 of the second
end portion 91 such the pressure varies in the direction in which the second end
portion 91 extends, whereby the crests 100 and the roots 101 are formed on the
second end portion 91. In the method for manufacturing the electric motor 40, the
20 first end portion 81 and the second end portion 91 are joined together by applying the
joining material 75 such that the joining material 75 covers the crests 100 and the
roots 101 on the second end portion 91. The above joining process is performed
after the above application of the pressure.
[0094]
25 As a result, the joining material 75 easily reaches the roots 101, which are
recessed from the crests 100, on the outer peripheral surface 93 of the second end
portion 91. Thus, particularly at the roots 101, the joining material 75 easily flows
through the spaces between the second electric wires and easily reaches the first end
portion 81, and the first end portion 81 and the second end portion 91 can thus be
30 satisfactorily joined together.
32
[0095]
Embodiments 1 to 3 can be combined, or be modified or omitted as
appropriate. For example, Embodiments 2 and 3 can be combined such that the
helical portions of the second end portion 91 adjoin each other and the distal end
5 portion 92 of the second end portion 91 is located inward of the circular outline of the
outer peripheral surface 93 of the second end portion 91.
Reference Signs List
[0096]
9: rolling piston, 10: refrigeration cycle apparatus, 11: refrigerant circuit, 12:
10 compressor, 13: flow switching device, 13a: cylinder chamber, 14: outdoor heat
exchanger, 15: pressure reducing device, 16: indoor heat exchanger, 17: controller,
20: hermetic container, 20a: upper lid, 20b: lower lid, 20c: tubular body, 21: suction
pipe, 22: discharge pipe, 23: suction muffler, 24: terminal unit, 24a: terminal, 25:
refrigerating machine oil, 30: compression element, 31: cylinder, 31a: cylinder
15 chamber, 32: rolling piston, 33: main bearing, 34: auxiliary bearing, 35: discharge
muffler, 40: electric motor, 41: stator, 42: rotor, 43: stator core, 43a: slot, 43b: cut, 43t:
teeth, 43y: yoke, 44: stator winding, 44a: other end portion, 45: lead, 45u: U-phase
lead, 45v: V-phase lead, 45w: W-phase lead, 46: rotor iron core, 46a: rotor slot, 47:
end ring, 48: conductor, 50: crankshaft, 51: eccentric shaft portion, 52: main shaft
20 portion, 53: auxiliary shaft portion, 61: U-phase winding portion, 61a: joint portion, 62:
V-phase winding portion, 62a: joint portion, 63: W-phase winding portion, 63a: joint
portion, 64: U-phase copper wire, 64a: U-phase copper wire coil, 64b: U-phase
copper wire coil, 64c: U-phase copper wire coil, 64d: U-phase copper wire coil, 64e:
U-phase copper wire terminal portion, 65: U-phase aluminum wire, 65a: U-phase
25 aluminum wire coil, 65b: U-phase aluminum wire coil, 65c: U-phase aluminum wire
coil, 65d: U-phase aluminum wire coil, 65e: U-phase aluminum wire terminal portion,
66: V-phase copper wire, 66a: V-phase copper wire coil, 66b: V-phase copper wire
coil, 66c: V-phase copper wire coil, 66d: V-phase copper wire coil, 66e: V-phase
copper wire terminal portion, 67: V-phase aluminum wire, 67a: V-phase aluminum
30 wire coil, 67b: V-phase aluminum wire coil, 67c: V-phase aluminum wire coil, 67d: V-
33
phase aluminum wire coil, 67e: V-phase aluminum wire terminal portion, 68: W-phase
copper wire, 68a: W-phase copper wire coil, 68b: W-phase copper wire coil, 68c: Wphase copper wire coil, 68d: W-phase copper wire coil, 68e: W-phase copper wire
terminal portion, 69: W-phase aluminum wire, 69a: W-phase aluminum wire coil, 69b:
5 W-phase aluminum wire coil, 69c: W-phase aluminum wire coil, 69d: W-phase
aluminum wire coil, 69e: W-phase aluminum wire terminal portion, 70: joint portion,
70a: neutral point, 71: insulating material, 75: joining material, 80: first electric wire
bundle, 81: first end portion, 82a: first end face, 90: second electric wire bundle, 91:
second end portion, 91a: first helical portion, 91b: second helical portion, 92: distal
10 end portion, 92a: second end face, 93: outer peripheral surface, 100: crest, 101: root,
Ax: rotational axis, C1: center, D1: outer diameter, D2: outer diameter, G: gap.

WE CLAIM:
[Claim 1]
An electric motor for a compressor, comprising a stator including a stator
winding,
5 wherein the stator winding includes
a first electric wire bundle having a first end portion and a first end face,
the first end portion including end portions of a plurality of first electric wires and being
formed in the shape of a wire bundle, the end portions of the plurality of first electric
wires being bundled and twisted, the first end face being located at a distal end of the
10 first end portion,
a second electric wire bundle including a plurality of second electric
wires, the second electric wire bundle having a second end portion wound helically
around the first end portion of the first electric wire bundle, and
an insulating material covering the first end portion and the second end
15 portion,
wherein the second end portion is wound to cover an edge portion of the first
end face of the first electric wire bundle,
wherein the second electric wire bundle has a second end face at an end of the
second end portion, and
20 wherein the second end face of the second electric wire bundle is located to
extend from a circular outline of an outer peripheral surface of the second end portion
or from a region located inward from the circular outline.
[Claim 2]
The electric motor for a compressor of claim 1, wherein the second end face of
25 the second electric wire bundle is located inward of the circular outline of the outer
peripheral surface of the second end portion.
[Claim 3]
The electric motor for a compressor of claim 1 or 2, further comprising a joining
material joining the first end portion and the second end portion together,
35
wherein the second end portion includes a crest and a root that are alternately
arranged in a direction in which the first end portion extends, the root being recessed
from the crest and having an outer diameter less than an outer diameter of the crest,
and
5 wherein the joining material covers the crest and the root of the second end
portion.
[Claim 4]
A compressor comprising:
the electric motor for a compressor of any one of claims 1 to 3;
10 a compression element configured to be driven by the electric motor to
compress fluid sucked from outside; and
a hermetic container housing the electric motor and the compression element.
[Claim 5]
A refrigeration cycle apparatus comprising:
15 the compressor of claim 4;
an outdoor heat exchanger;
an expansion valve; and
an indoor heat exchanger.
[Claim 6]
20 A method for manufacturing an electric motor for a compressor, the electric
motor including a stator including a stator winding,
wherein the stator winding includes
a first electric wire bundle having a first end portion and a first end face,
the first end portion including end portions of a plurality of first electric wires and being
25 formed in the shape of a wire bundle, the end portions of the plurality of first electric
wires being bundled and twisted, the first end face being located at a distal end of the
first end portion,
a second electric wire bundle including a plurality of second electric
wires and having a second end portion wound helically around the first end portion of
30 the first electric wire bundle, and
36
an insulating material covering the first end portion and the second end
portion,
the method comprising:
applying a pressure to an outer peripheral surface of the second end portion
5 from outside, in a state in which the second end portion is wound to cover an edge
portion of the first end face of the first electric wire bundle and a second end face at
an end of the second end portion is located to extend from a circular outline of the
outer peripheral surface of the second end portion or from a region located inward of
the circular outline.
10 [Claim 7]
The method for manufacturing the electric motor for a compressor of claim 6,
wherein in the applying the pressure, the pressure is applied to the outer peripheral
surface of the second end portion such that the pressure varies in a direction in which
the second end portion extends, thereby forming a crest and a root on the second
15 end portion,
the method further comprising:
joining the first end portion and the second end portion together by applying a
joining material such that the joining material covers the crest and the root on the
second end portion, the joining the first end portion and the second end portion
20 together being performed after the applying the pressure.