CN115378153B

CN115378153B - Motor cores, scroll compressors and refrigeration equipment

Info

Publication number: CN115378153B
Application number: CN202211033288.3A
Authority: CN
Inventors: 李玉斌; 魏会军; 吕浩福; 刘韵; 韦衍
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2025-08-05
Anticipated expiration: 2042-08-26
Also published as: CN115378153A

Abstract

The invention provides a motor iron core, a scroll compressor and refrigeration equipment, and relates to the technical field of compressors. The motor iron core comprises a rotor iron core and a stator iron core sleeved on the rotor iron core, and is characterized in that the inner surface of the stator iron core and/or the outer surface of the rotor iron core is a conical surface, so that an air gap with the width gradually increasing along the axial direction of the iron core is formed between the stator iron core and the rotor iron core. Based on the technical scheme of the invention, the air gap unevenness is reduced, the increase of the air gap magnetic resistance is not too large, and the optimization is achieved between the air gap magnetic resistance and the air gap uniformity, so that the fluctuation rate of the air gap magnetic resistance is reduced, the radial electromagnetic force fluctuation rate is reduced, and finally the electromagnetic vibration and electromagnetic noise of the whole compressor are effectively reduced.

Description

Motor iron core, scroll compressor and refrigeration equipment

Technical Field

The invention relates to the technical field of compressors, in particular to a motor iron core, a scroll compressor and refrigeration equipment.

Background

The motor iron core is an important component part of the compressor, and particularly, the scroll compressor has the outstanding advantages of small vibration, few parts and high reliability, and is widely applied to the field of refrigeration and air conditioning. Similar to other hermetic refrigeration compressors, the basic structure of the scroll compressor is also composed of a mechanical pump unit and a motor unit enclosed in a fully hermetic shell. The mechanical pump body unit is used for sucking and discharging the refrigerant, the compressor and the motor unit is used for providing needed power. In general, the energy supply of the motor unit and the mechanical pump body unit requires a main shaft to be transmitted, one end of the shaft is thermally sleeved in a motor rotor, the other end of the shaft drives the pump body through a certain structure, a motor stator is sleeved outside the motor rotor, and the motor stator is arranged on the shell. For scroll compressors, two rolling bearings (referred to as primary and secondary bearings) are typically employed to locate and support the main shaft.

The axes of the main bearing and the auxiliary bearing are difficult to completely coincide, and certain deviation exists, and the deviation is measured by coaxiality. Therefore, the non-coaxial main and auxiliary bearings will cause the axis of the main shaft and the rotor thermally sleeved on the main shaft to incline relative to the axis of the shell and the motor stator core, and as a direct consequence, the gap between the stator and the rotor is uneven. Uneven gaps between the stator and the rotor can lead to increased radial electromagnetic force fluctuation of the motor, and further increase of electromagnetic noise. Electromagnetic noise is generally distributed in the medium-frequency and low-frequency bands, and the medium-frequency and low-frequency noise has strong penetrability and is not easy to shield and eliminate, so that the electromagnetic noise is of great significance.

Disclosure of Invention

Aiming at the problem that radial electromagnetic force fluctuation of a motor is increased and electromagnetic noise is increased due to uneven air gap between a stator and a rotor of a vortex compressor in the prior art, the application provides a motor iron core, an vortex compressor and refrigeration equipment, which can reduce air gap unevenness and electromagnetic noise.

In a first aspect, the present invention proposes a motor core, including a rotor core and a stator core sleeved on the rotor core, where an inner surface of the stator core and/or an outer surface of the rotor core are conical surfaces, so that an air gap with a width gradually increasing along an axial direction of the core is formed between the stator core and the rotor core.

In one embodiment, an included angle θ is formed between an inner surface of the stator core and an outer surface of the rotor core, and θ satisfies the following relationship:

Wherein C is the coaxiality of a first bearing and a second bearing corresponding to the two ends of a main shaft where the rotor core is located, L is the distance between the first bearing and the second bearing, and lambda is a constant smaller than 1. According to the embodiment, the inclination degree of the conical surface of the rotor core or the stator core is limited, the air gap unevenness is reduced, meanwhile, the increase of the air gap magnetic resistance is avoided from being too large, and the air gap magnetic resistance and the air gap uniformity are optimized.

In one embodiment, the value of λ ranges from 0.3 to 0.6. With the present embodiment, the value range is further determined for a λ constant smaller than 1.

In one embodiment, the inner surface of the stator core and the outer surface of the rotor core are both conical surfaces. According to the present embodiment, the conical surfaces of the inner surface of the stator core and the outer surface of the rotor core can be processed separately, and the conical surfaces of the stator core and the conical surfaces of the rotor core are inclined in opposite directions, so that the process requirements when the microminiature rotor core or the stator core needs to be processed can be reduced.

In one embodiment, the taper angle of the taper surface of the stator core is θ ', and the taper angle of the taper surface of the rotor core is θ ", so that θ' +θ" =θ. In this embodiment, the taper angle that would otherwise be required to be individually machined into the stator core or the rotor core is divided into two parts, and the two parts are machined into the stator core and the rotor core.

In one embodiment, the taper angle of the taper surface of the stator core is equal to the taper angle of the taper surface of the rotor core.

In one embodiment, the generatrix of the conical surface is a straight line or a curve.

In one embodiment, the width of the air gap increases uniformly along the core axis. Through this embodiment, guarantee rotor core and stator core's surface smoothness, noise reduction.

In a second aspect, the present invention provides a scroll compressor comprising the above-described motor core.

In a third aspect, the present invention provides an intelligent device comprising the above scroll compressor.

The above-described features may be combined in various suitable ways or replaced by equivalent features as long as the object of the present invention can be achieved.

Compared with the prior art, the motor iron core, the scroll compressor and the refrigeration equipment provided by the invention have the following beneficial effects:

the width of the air gap between the stator iron core and the rotor iron core is gradually increased along the axial direction of the iron core, so that the air gap unevenness is reduced, the increase of the air gap magnetic resistance is not too large, the air gap magnetic resistance and the air gap uniformity are optimized, the fluctuation rate of the air gap magnetic resistance is reduced, the radial electromagnetic force fluctuation rate is reduced, and finally the electromagnetic vibration and electromagnetic noise of the whole compressor are effectively reduced.

Drawings

The invention will be described in more detail hereinafter on the basis of embodiments and with reference to the accompanying drawings. Wherein:

FIG. 1 shows a schematic top view of a stator core with increased air gap from a rotor core;

fig. 2 shows a schematic front view in cross section of an increase in the inner diameter of the stator core;

FIG. 3 shows a schematic cross-sectional front view of a rotor core with reduced outer diameter;

fig. 4 shows a schematic view of the installation positions of the stator core and the rotor core of the present invention;

FIG. 5 shows a comparative schematic of spindle axis tilt;

FIG. 6 shows a top-down comparison schematic of a rotor core offset relative to a stator core;

FIG. 7 shows a schematic front view cross-section contrast diagram of a rotor core offset relative to a stator core;

in the drawings, like parts are designated with like reference numerals. The figures are not to scale.

Reference numerals:

10-rotor core, 20-stator core, 30-main shaft, 31-first bearing, 32-second bearing.

Detailed Description

The invention will be further described with reference to the accompanying drawings.

Example 1

The invention provides a motor iron core, which comprises a rotor iron core 10 and a stator iron core 20 sleeved on the rotor iron core, wherein the inner surface of the stator iron core 20 and/or the outer surface of the rotor iron core 10 are conical surfaces, so that an air gap with gradually increased width along the axial direction of the iron core is formed between the stator iron core 20 and the rotor iron core 10.

Specifically, as shown in fig. 1-3, the air gap between the stator core 20 and the rotor core 10 is gradually increased along the axial direction of the core, so that not only is the air gap unevenness reduced, but also the increase of the air gap magnetic resistance is not excessive, and the optimization is achieved between the air gap magnetic resistance and the air gap uniformity, so that the fluctuation rate of the air gap magnetic resistance is reduced, the radial electromagnetic force fluctuation rate is reduced, and finally the electromagnetic vibration and electromagnetic noise of the whole compressor are effectively reduced.

It should be further noted that electromagnetic noise is still mechanical in nature and is simply mechanical noise caused by mechanical vibrations caused by electromagnetic forces acting on the motor core. Electromagnetic noise alone is listed as a type of noise because the generation mechanism of electromagnetic force is quite different from mechanical force. The air gap between the stator core 20 and the rotor core 10 has an important influence on electromagnetic noise. In fact, the air gap, having a radial length, constitutes the most predominant reluctance in the magnetic circuit of the motor. The magnetic field energy of the motor is substantially concentrated in the air gap reluctance. And the magnetic flux of the motor is determined by dividing the magnetomotive force of the motor by the reluctance. When the change of the length of the air gap is small, namely the change of the magnetic resistance of the air gap is also small, the change of magnetic flux is small, and the corresponding electromagnetic force change is small. According to the vibration theory, it is known that the reason for the large vibration of the mechanical member is not the magnitude of the external force, but the magnitude of the external force change, and therefore, the magnitude of the air gap reluctance change, rather than the magnitude of the air gap reluctance itself, is a determining factor for determining the electromagnetic force change and thus the magnitude of the electromagnetic noise.

From the above, the non-uniformity of the air gap distribution of the stator and the rotor of the motor is an important factor affecting electromagnetic noise. The non-uniformity of the stator-rotor air gap, also called the fluctuation rate, is reduced, and electromagnetic noise can be effectively restrained. As shown in fig. 6 and 7, the left side structure in fig. 6 and 7 is a schematic view in which the inner surface of the stator core 20 and the outer surface of the rotor core 10 are both cylindrical, and the right side structure is a schematic plan view and a front sectional view when the stator core 20 and the rotor core 10 are inclined relatively, and at this time, the air gap unevenness between the stator core 20 and the rotor core 10 is denoted as δ, satisfying the following formula (2):

In the above (2), C _max is the maximum air gap width, C _min is the minimum air gap width, D is the inner diameter of the stator core 20, D is the outer diameter of the rotor core 10, and (D-D)/2 is the air gap average value.

As is apparent from the above equation (2), if the inner diameter of the stator core 20 is increased by 2 Δ and the outer diameter of the rotor core 10 is kept unchanged, the maximum air gap and the minimum air gap are each increased by Δ, and the air gap unevenness at this time is δ', satisfying the following equation (3):

as is clear from the comparison between the formulas (2) and (3), when the value of δ' is smaller than the value of δ, the air gap unevenness between the stator core 20 and the rotor core 10 is reduced after the inner diameter of the stator core 20 is increased by 2Δ, which results in reduction of the radial electromagnetic force fluctuation, thereby reducing the corresponding electromagnetic noise.

Similarly, according to the above formula (2), if the outer diameter of the rotor core 10 is reduced by 2 Δ and the inner diameter of the stator core 20 is kept unchanged, the maximum air gap and the minimum air gap are each increased by Δ, and the air gap unevenness at this time is δ ", satisfying the following formula (4):

it can be seen that the air gap non-uniformity at this time will also decrease, which will also result in a decrease in radial electromagnetic force fluctuations, which in turn reduces the corresponding electromagnetic noise. The above is the scientific principle on which the present application is based.

In practice, the angle of inclination of the main shaft 30 due to the axis misalignment of the first bearing 31 and the second bearing 32 is generally about 0.1 °, and the delta value when the stator core 20 or the rotor core 10 is conically designed is generally smaller than 0.15 mm.

Example 2

The present embodiment is further optimized based on embodiment 1 in that an angle θ is formed between the inner surface of the stator core 20 and the outer surface of the rotor core 10, satisfying the following relational expression (1):

In the above formula (1), λ=0.3 to 0.6, c is the coaxiality of the first bearing 31 and the second bearing 32, which are sleeved on the main shaft 30 penetrating through the rotor core 10, and L is the distance between the first bearing 31 and the second bearing 32. As shown in fig. 5, the left side structure is a schematic diagram of the positional relationship with the stator core 20 when the first bearing 31 and the second bearing 32 are theoretically coaxial, and the right side structure is a schematic diagram of the positional relationship with the stator core 20 when the first bearing 31 and the second bearing 32 are not coaxial. The degree of inclination of the conical surface of the rotor core 10 or the stator core is limited, the air gap unevenness is reduced, and meanwhile, the increase of the air gap magnetic resistance is avoided from being excessively large, and the optimization is achieved between the air gap magnetic resistance and the air gap uniformity. When the inner surface of the stator core 20 is a conical surface, the outer surface of the rotor core 10 is cylindrical, and when the outer surface of the rotor core 10 is a conical shape, the inner surface of the stator core 20 is cylindrical.

Specifically, an included angle θ between the inner surface of the stator core 20 and the outer surface of the rotor core 10 is more specifically described as a cut surface obtained by cutting along an axis after the stator core 20 and the rotor core 10 are assembled, as shown in fig. 2 and 3, where θ is an included angle between an outline edge line of the outer side of the stator core 20 and an outline edge line of the inner side of the rotor core 10. If the inner diameter dimension of the stator core 20 is only fixedly increased in the axial direction, or the outer diameter dimension of the rotor core 10 is fixedly reduced, that is, the stator core 20 or the rotor core 10 after the change in dimension is kept cylindrical, the air gap reluctance becomes excessively large, resulting in an increase in motor power and a decrease in efficiency.

Further, the values of λ are 0.3, 0.4, 0.5, 0.6, etc., and λ is empirically determined, reflecting the fact that the angles determined by the parameters C and L in equation (1) are probability events, i.e., the angles determined by C and L are relatively low, and therefore, the actual determination of the cone angle θ is a discount and is multiplied by a coefficient λ smaller than 1.

Example 3

The present embodiment is further optimized based on embodiment 2 in that the inner surface of the stator core 20 and the outer surface of the rotor core 10 are both conical surfaces. The conical surfaces can be processed on the inner surface of the stator core 20 and the outer surface of the rotor core 10, respectively, and the conical surfaces of the stator core 20 are opposite to the inclined direction of the conical surfaces of the rotor core 10, so that the process requirements when the microminiature rotor core 10 or the stator core 20 is required to be processed are reduced. The taper angle of the taper surface of the stator core 20 is θ ', and the taper angle of the taper surface of the rotor core 10 is θ ", satisfying θ' +θ" =θ. Further, θ' =θ ", when one of the stator core 20 and the rotor core 10 is more difficult to process for the micro-compressor, the taper angle of the more difficult to process member may be set smaller than that of the other more easy to process member. The taper angle that would otherwise be required to be individually machined to the stator core 20 or the rotor core 10 is divided into two parts, and machined to the stator core 20 and the rotor core 10, respectively.

Specifically, in the case where process requirements are satisfied for a large compressor motor or the like, conical surfaces may be simultaneously machined on the inner surface of the stator core 20 or the outer surface of the rotor core 10, and the sum of the conical angles of the conical surfaces of the stator core 20 and the rotor core 10 is equal to or slightly smaller than the conical angle when the conical surface is machined on one of the stator core 20 and the rotor core 10 alone. When a conical surface is machined at the same time on the inner surface of the stator core 20 or the outer surface of the rotor core 10, the inner diameter of the stator core 20 gradually increases in the axial direction, and at this time, the outer diameter of the rotor core 10 gradually decreases in the direction.

The included angle between the axes of the rotor core 10 and the stator core 20 is 0.05-0.15 degrees. Specifically, the rotor core 10 is thermally sleeved on the main shaft 30, the first bearing 31 and the second bearing 32 sleeved on the main shaft 30 are respectively located at two sides of the rotor core 10, the axes of the first bearing 31 and the second bearing 32 are difficult to completely coincide, and a certain deviation exists, so that a certain included angle is formed between the axis of the rotor core 10 and the axial direction of the stator core 20 as a direct result. Other undescribed portions are the same as those of the above embodiments, and thus are not described in detail.

Example 4

The generatrix of the conical surface is a straight line or a curve. The condition that the width of the air gap gradually increases is satisfied. The width of the air gap is uniformly increased along the axial direction of the iron core, so that the surface smoothness of the rotor iron core 10 and the stator iron core 20 is ensured, and the wind resistance is reduced. Other undescribed portions are the same as those of the above embodiments, and thus are not described in detail.

Example 5

The invention provides a scroll compressor, which comprises the motor iron core and further has all technical effects.

Example 6

The invention provides intelligent equipment, which comprises the scroll compressor and further has all technical effects.

In the description of the present invention, it should be understood that the terms "upper," "lower," "bottom," "top," "front," "rear," "inner," "outer," "left," "right," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present invention and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be configured and operated in a particular orientation, and thus should not be construed as limiting the present invention.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the different dependent claims and the features described herein may be combined in ways other than as described in the original claims. It is also to be understood that features described in connection with separate embodiments may be used in other described embodiments.

Claims

1. A motor core, comprising a rotor core and a stator core sleeved thereon, wherein the inner surface of the stator core and the outer surface of the rotor core are conical surfaces, so that an air gap is formed between the stator core and the rotor core, the width of the air gap gradually increasing along the axial direction of the core;

The conical angle of the conical surface of the stator core is θ', the conical angle of the conical surface of the rotor core is θ", and an angle θ is formed between the inner surface of the stator core and the outer surface of the rotor core, satisfying θ'+θ"=θ.

2. The motor core according to claim 1, wherein θ satisfies the following relationship:

Wherein, C is the coaxiality of the first bearing and the second bearing corresponding to the two ends of the main shaft where the rotor core is located, L is the distance between the first bearing and the second bearing, and λ is a constant less than 1.

3 . The motor core according to claim 2 , wherein the value range of λ is 0.3 to 0.6.

4 . The motor core according to claim 1 , wherein the cone angle of the conical surface of the stator core is equal to the cone angle of the conical surface of the rotor core.

The motor core according to claim 1 , wherein the generatrix of the conical surface is a straight line or a curve.

6 . The motor core according to claim 1 , wherein the width of the air gap increases uniformly along the axial direction of the core.

7. A scroll compressor, characterized by comprising the motor core according to any one of claims 1 to 6.

8. A refrigeration device, comprising the scroll compressor according to claim 7.