CN110784027A

CN110784027A - Stator, motor using the same, and compressor

Info

Publication number: CN110784027A
Application number: CN201910161790.4A
Authority: CN
Inventors: 平山宏
Original assignee: Hitachi Global Life Solutions Inc
Current assignee: Hitachi Global Life Solutions Inc
Priority date: 2018-07-31
Filing date: 2019-03-04
Publication date: 2020-02-11
Also published as: JP2020022242A

Abstract

The invention relates to a stator, a motor using the stator and a compressor, aiming at improving the insulation of the stator. The stator includes: a stator core having teeth and grooves; and an insulator mounted axially inward from an axial end of the stator core, wherein the insulator has: a bridge portion located at a circumferential end portion of the stator core; a root portion extending in an axial direction of the stator core and approaching the bridge portion; and a leading end portion extending in a direction away from the bridge portion, the leading end portion having a gap with the stator core.

Description

Stator, motor using the same, and compressor

Technical Field

The present invention relates to a stator, and a motor and a compressor using the stator.

Background

Patent document 1 discloses a corner coating portion having an L-shaped cross section that covers only the corner portions of the teeth. Further, as in patent document 2, a structure in which two insulators are butted to each other is also known.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2002-

Patent document 2: japanese laid-open patent publication No. 61-218335

Disclosure of Invention

Problems to be solved by the invention

In the case of a stator-wound coil wire formed of metal, it is required to ensure insulation between the stator and the wire. When insulating paper formed of a film of polyester or the like is used as an insulating material in the groove of the stator core, there is a problem that the insulating paper is deformed, damaged, or displaced during a winding operation, and insulation between the core and the coil winding (enameled wire) is insufficient.

In the structure that covers only the corner portion as in patent document 1, there is a problem that insulation reliability is insufficient depending on the usage environment of the motor and the like. On the other hand, if two insulators are butted and the entire circumference is covered as in patent document 2, the winding space of the coil winding is occupied by the insulator, resulting in a large motor.

In addition, the coil of the motor passes a current through the magnetic field, and thus acts on the conductor. Therefore, a force to vibrate the coil is generated by the commutation flow of the coil when the motor is operated. Therefore, it is preferable to reduce the contact area of the coil with the stator core.

Means for solving the problems

In view of the above circumstances, the present invention is a stator including: a stator core having teeth and grooves; and an insulator attached to the stator core from an axial end portion thereof to an axial inner side, wherein the insulator includes: a bridge portion located at an axial end portion of the stator core; a base portion extending in an axial direction of the stator core and being adjacent to the bridge portion; and

and a tip portion extending in a direction away from the bridge portion, the tip portion having a gap with the stator core.

Drawings

Fig. 1 is a plan view (a) and a perspective view (b) of a stator of a motor according to embodiment 1.

Fig. 2 is a developed view of a stator showing an insulation structure of the stator of fig. 2.

Fig. 3 is a perspective view of an insulator of embodiment 1.

Fig. 4 is a sectional view a-a of fig. 1.

Fig. 5 is an enlarged view of fig. 4.

Fig. 6 is a longitudinal sectional view of a hermetic compressor mounted with the motor of embodiment 1.

Fig. 7 is a longitudinal sectional view of a refrigerator mounted with the hermetic compressor of fig. 6.

Description of the symbols

1-motor, 3-stator, 4-stator core, 4 a-groove, 4 b-tooth, 4 c-yoke, 5-coil, 6-insulator, 6 a-base, 6 b-tip, 6 c-bridge, 7-groove insulation paper, 32-rotor, 50-hermetic compressor, 100-refrigerator.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and may be any household electrical appliance such as an air conditioner and a heat pump water heater, which is equipped with a hermetic compressor. In the embodiments described below, a refrigerator is described as an example of a home appliance.

[ example 1 ]

Fig. 1 is a plan view (a) and a perspective view (b) of a stator 3 of the motor of the present embodiment, and fig. 2 is a development view of the stator 3 showing a structure of a stator core and an insulating material. Fig. 3 is a perspective view of the insulator 6, and fig. 4 is a sectional view a-a of fig. 1, showing a structure of an insulating material around a tooth portion around which a coil is wound. Fig. 5 is an enlarged view of fig. 4.

A plurality of slots 4a and teeth 4b are annularly arranged in the stator core 4, and the coil 5 is wound around the teeth 4 b. At this time, in order to insulate the coil 5 from the stator core 4, a groove insulating paper 7 having a shape along the gap-side circumference of the groove 4a is provided in the groove 4a, and insulators 6 are disposed at both axial end portions of the stator core 4. Thus, the groove insulating paper 7 covers the tooth side periphery, and the insulator 6 covers the teeth 4 b.

As shown in fig. 4, the insulator 6 is substantially コ -shaped and is disposed on each of the axial end sides of the teeth 4 b. The

groove insulating walls

6a and 6b, which are portions to be inserted into the groove 4a, have a base portion 6a on the base side (both axial end sides) thicker than a tip portion 6b on the tip side. The bridge portion 6c is a portion that contacts an axial end of the tooth 4 b. When attached to the stator core 4, the root portion 6a and the bridge portion 6c contact the stator core 4 (teeth 4b), and the tip portion 6b has a gap. The end side of the slot insulating paper 7 is inserted into the gap, and the slot insulating paper 7 is supported between the stator core 4 and the insulator 6.

As shown in fig. 5, the dimensions are defined as follows.

Thickness of root base 6 a: t1

Thickness of the tip portion 6 b: t2

Length of root base 6 a: l1

Length of tip portion 6 b: l2

Overlapping length of the insulating paper 7 and the distal end portion 6 b: as D

As shown in fig. 4, the axial length of the teeth 4b is Lst.

In the present embodiment, the corner of the tooth 4b is covered by the root base 6a, and the portion ahead of the corner is covered by the leading end 6b and the insulating paper 7 is supported. Since the tip portion 6b has a gap with the teeth 4b, it is difficult to transmit the vibration from the coil winding.

Further, the distal end portions 6b of the two insulators 6 facing each other are separated. Therefore, the transmission of vibration between the distal end portions 6b can be suppressed, and the volume occupied by the insulator 6 is reduced, so that the space factor of the coil winding can be easily increased. The distance separating the distal end portions 6b can be, for example, about 1/3 of the axial dimension of the teeth 4 b.

In the present embodiment, the structure is configured to have a size of 1/2 × Lst > L1+ L2 > 1/3 × Lst. In addition, the dimension D is preferably 2.4mm or more in a motor mounted on, for example, a hermetic compressor, from the viewpoint of ensuring insulation according to the study of the present inventors. The L2 size is determined in such a way that it is also satisfied at the combination of the largest tolerance sizes.

With this structure, since the length of 2/3 or more in the groove of the stator core 4 is covered with the insulating wall of the insulator 6 having high rigidity and heat resistance, the insulating performance can be greatly improved as compared with the case where the insulation in the groove 4a is performed only by the insulating paper 7.

In order to secure the insulation distance between the stator core 4 and the coil winding, the groove insulating paper 7 and the plate thickness t2 of the insulator 6 are overlapped at the boundary between the insulating materials 6 and 7 by a required creepage distance. Since the thickness of the groove insulating paper 7 can be made thinner than half or less than the thickness of the insulator 6, the influence on the groove area is smaller than the thickness of the two insulators 6 stacked one on another.

Fig. 6 is a longitudinal sectional view of a hermetic compressor mounted with a motor, and fig. 7 is a longitudinal sectional view of a refrigerator mounted with a hermetic compressor. The hermetic compressor configured in the hermetic container 50 of fig. 6 includes: a motor unit 1 including a rotor 32 rotatably provided and a stator 3 formed by winding an armature in a plurality of recesses formed along a cylindrical inner circumferential surface of a stator core facing an outer circumferential surface of the rotor; a power transmission unit including a crankshaft 35 coupled to the rotor and a link 36 for converting the rotational motion of the crankshaft into the reciprocating motion of a piston 37; and a compressor mechanism portion including a valve plate 19 for compressing refrigerant gas in the cylinder 38 by reciprocating the piston 37 and controlling suction and discharge of the refrigerant gas.

The motor 1 rotates the rotor 32 together with the shaft 35 by an electromagnetic force generated in the stator 3 by flowing a current through the coil. The stator 3 is formed by winding coils of respective phases around respective slots of a stator core formed by laminating electromagnetic copper plates, and has an insulating material between the stator core and the coils.

Claims

1. A stator, having: a stator core having teeth and grooves; and an insulator mounted axially inward from an axial end of the stator core,

the above-described stator is characterized in that,

the insulator includes:

a bridge portion located at an axial end portion of the stator core;

a base portion extending in an axial direction of the stator core and being adjacent to the bridge portion; and

a front end portion extending in a direction away from the bridge portion,

the tip portion has a gap with the stator core.

2. The stator according to claim 1,

the groove insulation paper is inserted into the groove, and the end part of the groove insulation paper is inserted into the gap.

3. The stator according to claim 1 or 2,

the sum of the axial lengths of the root base portion and the tip end portion is greater than 1/3 and less than 1/2 of the axial length of the stator core.

4. A hermetic compressor is characterized in that,

the stator of claim 2 having said gap in an axial dimension of 2.4mm or more.

5. A motor having the stator according to any one of claims 1 to 3.

6. A compressor having the stator according to any one of claims 1 to 3.