CN213145101U - Radial protection bearing, magnetic suspension system adopting same and magnetic suspension compressor - Google Patents

Abstract

The utility model relates to a radial protection bearing and adopt its magnetic suspension system, magnetic suspension compressor, through establishing the outer ring cover in the inner ring periphery, the ball can roll ground and keep between inner ring and outer loop, first clearance h1 has in the footpath between ball and inner ring or the outer loop, second clearance h2 has in the axial, wherein, first clearance h 1's scope is 0.06mm-0.3mm, second clearance h 2's scope is 0.02mm-0.15mm, bearing wear has been reduced, the life of extension bearing, improve the impact resistance and the wearability of bearing, radial protection bearing is shock-resistant among the prior art has been solved, the problem of easy wearing and tearing, the reliability of magnetic suspension system and magnetic suspension compressor has been promoted.

Description

Radial protection bearing, magnetic suspension system adopting same and magnetic suspension compressor

Technical Field

The utility model relates to a bearing and adopt its magnetic suspension system, magnetic suspension compressor especially relate to a radial protection bearing and adopt its magnetic suspension system, magnetic suspension compressor.

Background

Magnetic levitation technology is the leading technology at present, and magnetic levitation technologies such as magnetic levitation trains, magnetic levitation compressors and the like are applied to various industries in different fields. The magnetic suspension centrifugal refrigeration compressor is a product which is currently most concerned in the refrigeration industry. The magnetic suspension centrifugal compressor has irreplaceable advantages in the industry due to the advantages of high running speed, high rotating precision, long service life and the like, and the magnetic suspension centrifugal compressor protective bearing is an indispensable part in a system as an important protective barrier after the magnetic suspension bearing fails.

The radial protection structure in the existing magnetic suspension system is generally made of materials with better self-lubricating performance, such as graphite, babbit metal, aluminum, polytetrafluoroethylene and the like, or a steel ball bearing is directly adopted as the protection bearing of the magnetic suspension system, and when the magnetic suspension bearing system fails, the protection structure can reduce the damage of the magnetic suspension bearing system to the maximum extent. However, the existing protection structure and the protection bearing do not have good impact resistance, and once suspension fails, the protection structure is violently impacted with the protection structure, the abrasion of the protection structure occurs, and then the whole magnetic suspension system is paralyzed.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a radial protection bearing and a magnetic suspension system and a magnetic suspension compressor using the same, which can solve the problems of the prior art that the radial protection bearing is not impact-resistant and is easy to wear, in particular,

a radial protection bearing comprises an inner ring, an outer ring and a ball outer ring, wherein the ball outer ring is sleeved on the periphery of the inner ring, balls can be held between the inner ring and the outer ring in a rolling mode, a first gap h1 is formed between the balls and the inner ring or the outer ring in the radial direction, and a second gap h2 is formed between the balls and the inner ring or the outer ring in the axial direction, the first gap h1 ranges from 0.06mm to 0.3mm, and the second gap h2 ranges from 0.02mm to 0.15 mm.

Preferably, the first gap h1 ranges from 0.06mm to 0.12mm and the second gap h2 ranges from 0.03mm to 0.08 mm.

Preferably, the radial protection bearing further comprises a retainer which is fitted over an outer surface of the ball and is in partial contact with the ball, and guides and retains the ball between the inner ring and the outer ring.

Preferably, the number of the balls is 10-32, so that the load bearing capacity of the radial protection bearing is enhanced.

Preferably, the accuracy grade of the balls is P5 grade or P6 grade, and the smoothness of the rotation of the balls between the inner ring and the outer ring is enhanced.

The utility model also provides a magnetic suspension system adopts the utility model provides a radial protection bearing.

The utility model also provides a magnetic suspension compressor adopts the utility model provides a radial protection bearing and/or magnetic suspension system.

Preferably, the compressor comprises a shell, a bearing seat is formed on the shell, the radial protection bearing is arranged in the bearing seat, a third gap H3 is arranged between the outer ring of the radial protection bearing and the inner wall of the bearing seat in the radial direction, and the third gap H3 ranges from 0.005mm to 0.05 mm.

Preferably, the compressor further comprises a motor rotor, a rotating shaft of the motor rotor extends into the inner ring of the radial protection bearing and has a fourth gap H4 with the inner ring of the radial protection bearing in the radial direction, and the fourth gap H4 is in the range of 0.1mm-0.3 mm.

Preferably, the compressor further comprises a protection member abutting against an end surface of the outer ring on a side away from the bearing seat and fixed with the bearing housing.

The utility model provides a radial protection bearing and adopt its magnetic suspension system, magnetic suspension compressor, through ball and interior ring or the outer loop between radially having first clearance h1, second clearance h2 has in the axial, the scope of first clearance h1 is 0.06mm-0.3mm, the scope of second clearance h2 is 0.02mm-0.15mm, make radial protection bearing atress balanced when high-speed operation and/or receive the impact, reinforcing radial protection bearing operation stationarity, wearability and impact resistance, bearing wear has been reduced, the life of extension bearing, reinforcing radial protection bearing, magnetic suspension system and magnetic suspension compressor's reliability, radial protection bearing is not resistant to impact among the prior art, the problem of easy wearing and tearing has been solved.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings. The drawings described below are merely some embodiments of the present disclosure, and other drawings may be derived from those drawings by those of ordinary skill in the art without inventive effort.

Fig. 1 is a front view of a radial protection bearing structure in an embodiment 1-3 of the present invention;

FIG. 2 is a side sectional view of a radial protective bearing structure according to embodiments 1-3 of the present invention;

fig. 3 is a rear view of a radial protective bearing structure according to embodiments 1-3 of the present invention;

fig. 4 is a sectional view of a compressor in embodiment 3 of the present invention;

fig. 5 is a partially enlarged sectional view of the compressor in embodiment 3 of the present invention;

FIG. 6 is a schematic diagram of the result of the optimization of the quality and reliability of the bearing in embodiment 3 of the present invention;

1-radial protection of the bearing; 11-inner ring; 12-an outer ring; 13-a ball bearing; 14-a cage; 2-a shell; 3-a protective element; 4-a two-stage diffuser; 5-a pre-sensor; 6-a motor rotor; h3 — third gap; h4-fourth gap.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings.

While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art so that they can be easily implemented by those skilled in the art. As can be readily understood by those skilled in the art to which the present invention pertains, embodiments to be described later may be modified into various forms without departing from the concept and scope of the present invention. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" include plural forms as well, unless the contrary is expressly stated. The term "comprising" as used in the specification embodies particular features, regions, constants, steps, actions, elements and/or components and does not exclude the presence or addition of other particular features, regions, constants, steps, actions, elements, components and/or groups.

All terms used below, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms defined in dictionaries are to be interpreted as meanings complied with in the relevant technical documents and the present disclosure, and cannot be interpreted as having a very formal meaning without definition.

Example 1:

the embodiment provides a radial protection bearing 1, the radial protection bearing 1 is applied to a magnetic suspension compressor, and comprises an inner ring 11, an outer ring 12 and balls 13, the outer ring 12 is sleeved on the outer periphery of the inner ring 11, the balls 13 are rollably held between the inner ring 11 and the outer ring 12, a first gap h1 is arranged between the balls 13 and the inner ring 11 or the outer ring 12 in the radial direction, and a second gap h2 is arranged in the axial direction, wherein the first gap h1 ranges from 0.06mm to 0.3mm, and the second gap h2 ranges from 0.02mm to 0.15mm, so that the radial protection bearing 1 is balanced in stress during high-speed operation and/or impact, and the wear resistance and impact resistance of the radial protection bearing 1 are enhanced.

The outer side of the inner ring 11 forms a first raceway, the inner side of the outer ring 12 forms a second raceway, and the balls 13 roll between the first raceway and the second raceway; the first gap h1 specifically refers to the moving amount of the radial protection bearing 1 when the inner ring 11 or the outer ring 12 is fixed and the balls 13 move radially between the first raceway and the second raceway when the radial protection bearing is not installed; the second gap h2 is specifically the moving amount of the radial protection bearing 1 when it is not installed, that is, when the inner ring 11 or the outer ring 12 is fixed and the balls 13 move axially between the first raceway and the second raceway.

The present embodiment may further preferably provide that the first gap h1 is in a range of 0.06mm to 0.12mm, the second gap h2 is in a range of 0.03mm to 0.08mm, and the first gap h1 and the second gap h2 in this range of values can provide good radial and axial protection for the radial protection bearing 1, so as to ensure that the radial protection bearing 1 is stressed more uniformly during high-speed operation and/or impact. When the first gap h1 and the second gap h2 are too large, the radial protection bearing 1 can generate strong vibration due to the large gaps when being used for protection. When the first gap h1 and the second gap h2 are too small, the radial protection bearing 1 plays a role in protection, and the temperature of the bearing cannot be increased due to the fact that heat cannot be better dissipated, and the service life of the bearing is affected. Therefore, the proper h1 and h2 are selected to ensure that the radial protection bearing can run stably, reduce the abrasion of the radial protection bearing 1, greatly prolong the service life of the radial protection bearing 1 and enhance the reliability of the radial protection bearing 1.

Preferably, the radial protection bearing 1 further comprises a retainer 14, and the retainer 14 is sleeved on the outer surface of the ball 13 and is partially contacted with the ball 13. Specifically, the cage 14 in this embodiment guides and retains the balls 13 between the inner ring 11 and the outer ring 12, partially wrapping the balls 13 and moving therewith.

Since the retainer 14 is also subjected to a large centrifugal force, impact and vibration when the radial protection bearing 1 is subjected to a complex load and/or operates at a high speed, and a large sliding friction exists between the retainer 14 and the balls 13, which may cause a failure, in the present embodiment, it is preferable that the retainer 14 is made of polyetheretherketone, which is an integral high-strength material, and compared with the retainer 14 made of a rigid material, the retainer 14 made of polyetheretherketone can reduce the dropping rate of the retainer 14 to 0%, so that the retainer 14 has strong high temperature resistance and impact resistance.

Preferably, the number of the balls 13 is 10 to 32; the present embodiment is further preferred that the number of the balls 13 is 15 to 26, which enhances the load bearing capacity of the radial protection bearing 1 and ensures the high-speed stable rotation thereof.

Preferably, the accuracy grade of the balls 13 is P5 grade or P6 grade, so that the smoothness of the rotation of the balls 13 between the inner ring 11 and the outer ring 12 is enhanced, and the rotation accuracy of the radial protection bearing 1 is ensured while the high rotation speed is achieved in a short time. The present embodiment is further preferred that the accuracy grade of the balls 13 is P5 grade, so that the rotation speed of the radial protection bearing 1 can reach 25000rpm in a short time, and can stably operate at 18000rpm for a long time.

Preferably, the ball 13 is made of a silicon nitride ceramic material, so that the radial protection bearing 1 has a self-lubricating function under an oil-free condition, can adapt to high-speed operation, and has high load bearing capacity, so that the retainer 14 of the radial protection bearing 1 is not damaged under severe impact, the overall mechanical property of the radial protection bearing 1 is enhanced, and the service life of the radial protection bearing 1 is prolonged.

The type of the radial protection bearing 1 in this embodiment is a ceramic radial protection bearing, and a hybrid ceramic radial protection bearing or an all-ceramic radial protection bearing may be used.

The embodiment provides a radial protection bearing, wherein a first gap h1 is arranged between a ball and an inner ring or an outer ring in the radial direction, a second gap h2 is arranged in the axial direction, the range of the first gap h1 is 0.06mm-0.12mm, and the range of the second gap h2 is 0.03mm-0.08mm, so that the wear of the bearing can be reduced, the service life of the bearing is prolonged, and the impact resistance and the wear resistance of the bearing are improved.

Example 2:

the present embodiment provides a magnetic levitation system which employs the radial protection bearing 1 provided in embodiment 1, has a self-lubricating function, can operate at high speed without oil, and has strong impact resistance and wear resistance.

Example 3:

the present embodiment provides a magnetic levitation compressor, which employs the radial protection bearing 1 provided in embodiment 1 and/or the magnetic levitation system provided in embodiment 2, and the compressor in this embodiment includes a housing 2, wherein a bearing seat is formed on the housing 2, the radial protection bearing 1 is disposed in the bearing seat, a third gap H3 is provided between the outer ring 12 of the radial protection bearing 1 and the inner wall of the bearing seat in the radial direction, and the third gap H3 is in a range of 0.005mm to 0.05 mm. Specifically, the compressor in the embodiment further comprises a second-stage diffuser 4 and a front sensor 5, wherein the front sensor 5 is arranged on one side of the rear of the second-stage diffuser 4, the radial protection bearing 1 is arranged in a bearing seat on one side of the rear of the front sensor 5, and one side of the outer ring 12 abuts against the side end face of the bearing seat; in this embodiment, bearing reliability analysis is further performed through DOE test, a range of the third gap H3 is preferably 0.009mm to 0.03mm, the third gap H3 in this numerical range can further reduce an impact force received when the radial protection bearing 1 is unstable, and enhance the impact resistance of the radial protection bearing 1, when the third gap H3 is too large, the radial protection bearing 1 is subjected to a large displacement in a radial direction after being subjected to the impact, so that a gap between the radial protection bearing 1 and a rotating shaft is not uniform, and further, the radial protection bearing 1 is subjected to uneven stress, and the service life is affected; when the third clearance H3 is too small, the difficulty of mounting and dismounting the radial protection bearing 1 increases.

Preferably, the magnetically levitated compressor further comprises a protection member 3, the protection member 3 abutting against an end surface of the outer ring 12 on a side away from the radial protection bearing 1 and being fixed with the housing 2. Specifically, the protection member 3 in this embodiment is a gland, and the gland abuts against the end face of the outer ring 12 on the side away from the bearing seat and is fixed to the housing 2 through screws, so that the radial protection bearing 1 can be blocked to a certain extent, the impact force applied when the motor rotor 6 falls to cause the instability of the radial protection bearing 1 is reduced, and the reliability of the radial protection bearing 1 and the magnetic suspension compressor is improved.

Preferably, the magnetic levitation compressor further comprises a motor rotor 6, wherein a rotating shaft of the motor rotor 6 extends into the inner ring 11 of the radial protection bearing 1 and has a fourth gap H4 in the radial direction with the inner ring 11 of the radial protection bearing 1, and the fourth gap H4 is in the range of 0.1mm-0.3 mm. Specifically, a circular hole is formed on the protection member 3, and a rotating shaft of the motor rotor 6 passes through the circular hole on the protection member 3 and extends into the inner ring 11 of the radial protection bearing 1; the embodiment may further preferably perform bearing reliability analysis through DOE test, where the range of the fourth gap H4 is 0.18mm to 0.25mm, and the fourth gap H4 in this numerical range is beneficial to prolonging the service life of the radial protection bearing 1 and improving the reliability of the compressor. When the fourth gap H4 is increased, the force of the rotor hitting the bearing is increased, and the service life of the bearing is affected. When the fourth gap H4 is too large, the radial protection bearing 1 cannot play a role in protection when the motor rotor 6 falls, and other pneumatic components in the compressor are directly impacted to cause part abrasion; when the fourth gap H4 is small, the magnetic suspension system is protected by the bearing frequently, and the magnetic suspension compressor cannot operate normally for a long time.

As shown in table 1, in the DOE (design of test) test performed in the present embodiment, the gap values of the third gap H3 and the fourth gap H4 are divided into two levels, i.e., high and low; then, DCE test (based on discrete selection test) analysis is carried out on the impact-resistant times of the bearing, so that the reliability of the bearing under different gaps is reflected, and the DCE test data are shown in Table 2; then, the bearing quality reliability is optimized according to the test data in table 2, the number of times of damage impact of the radial protection bearing 1 in this embodiment is set to be at least 200 times during optimization, and analysis of the optimization result shows that the bearing quality reliability can be maximized when the fourth gap H4 of the radial protection bearing 1 is at a high level (i.e., the fourth gap H4 ranges from 0.18mm to 0.25mm) and the third gap H3 is at a low level (from 0.009mm to 0.03mm), and the optimization result is shown in fig. 6.

TABLE 1 DOE test data

Factor(s)	Low level	High level
			Fourth gap H4	-1(0.12～0.18)	+1(0.18～0.25)
Third gap H3	-1(0.009～0.03)	+1(0.03～0.048)

TABLE 2 DCE test data

The embodiment provides a magnetic suspension compressor, wherein a radial protection bearing is arranged behind a secondary diffuser and a front sensor, a third gap H3 is arranged between an outer ring of the radial protection bearing and the inner wall of a bearing seat in the radial direction, and the range of the third gap H3 is 0.009mm-0.03 mm; the rotating shaft of the motor rotor and the inner ring of the bearing are provided with a fourth gap H4 in the radial direction, the range of the fourth gap H4 is 0.18mm-0.25mm, the impact force born by the bearing when the rotor falls can be reduced, the service life of the radial protection bearing 1 is prolonged, and the reliability of the compressor is improved.

To sum up, the utility model provides a radial protection bearing and adopt its magnetic levitation system, magnetic levitation compressor, through establish the periphery of inner ring with the outer ring cover, the ball can be kept between inner ring and outer ring rollingly, have first clearance h1 in the footpath between ball and inner ring or the outer ring, have second clearance h2 in the axial, wherein, the scope of first clearance h1 is 0.06mm-0.3mm, the scope of second clearance h2 is 0.02mm-0.15 mm; the abrasion of the bearing is reduced, the service life of the bearing is prolonged, the impact resistance and the abrasion resistance of the bearing are improved, and the problems that the radial protection bearing in the prior art is not impact resistant and is easy to abrade are solved, a third gap H3 is formed between the outer ring of the radial protection bearing and the inner wall of the bearing seat in the radial direction, and the range of the third gap H3 is 0.009mm-0.03 mm; the rotating shaft of the motor rotor and the inner ring of the bearing are provided with a fourth gap H4 in the radial direction, and the range of the fourth gap H4 is 0.18mm-0.25mm, so that the reliability of the magnetic suspension system and the magnetic suspension compressor is improved.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

Thus, it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been shown and described in detail herein, many other variations and modifications can be made, consistent with the principles of the invention, which are directly determined or derived from the disclosure herein, without departing from the spirit and scope of the invention. Accordingly, the scope of the present invention should be understood and interpreted to cover all such other variations or modifications.

Claims (10)

1. A radial protection bearing comprising an inner ring (11), an outer ring (12) and balls (13), the outer ring (12) fitting around the outer circumference of the inner ring (11), the balls (13) being rollably retained between the inner ring (11) and the outer ring (12), characterized in that there are first gaps h1 in the radial direction and second gaps h2 in the axial direction between the balls (13) and the inner ring (11) or the outer ring (12), wherein the first gap h1 ranges from 0.06mm to 0.3mm and the second gap h2 ranges from 0.02mm to 0.15 mm.

2. The radial protection bearing of claim 1, wherein the first gap h1 is in the range of 0.06mm to 0.12mm and the second gap h2 is in the range of 0.03mm to 0.08 mm.

3. The radial protection bearing of claim 2, further comprising a cage (14), wherein the cage (14) is disposed on an outer surface of the ball (13) and is in partial contact with the ball (13).

4. Radial protection bearing according to claim 3, wherein the number of balls (13) is 10-32.

5. Radial protection bearing according to claim 4, characterized in that the balls (13) have a precision grade of P5 or P6.

6. Magnetic levitation system, characterized in that a radial protection bearing (1) according to any of claims 1-5 is used.

7. A magnetic levitation compressor, characterized in that a radial protection bearing (1) according to any of claims 1-5 or a magnetic levitation system according to claim 6 is used.

8. The magnetic levitation compressor as claimed in claim 7, characterized in that the compressor comprises a housing (2), a bearing seat is formed on the housing (2), the radial protection bearing (1) is arranged in the bearing seat, a third gap (H3) is provided in the radial direction between an outer ring (12) of the radial protection bearing (1) and the inner wall of the bearing seat, and the third gap (H3) ranges from 0.005mm to 0.05 mm.

9. The magnetic levitation compressor as claimed in claim 7, characterised in that the compressor further comprises a motor rotor (6), the rotational shaft of the motor rotor (6) extending into the inner ring (11) of the radial protection bearing (1) and having a fourth gap (H4) in radial direction with the inner ring (11) of the bearing (1), the fourth gap (H4) being in the range of 0.1mm-0.3 mm.

10. The magnetic levitation compressor as claimed in claim 8, characterized in that the compressor further comprises a protection element (3), the protection element (3) resting against the end face of the outer ring (12) on the side remote from the bearing seat and being fixed to the housing (2).

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