CN114593149A

CN114593149A - Thrust disc assembly with slotting structure and magnetic suspension bearing

Info

Publication number: CN114593149A
Application number: CN202210291614.4A
Authority: CN
Inventors: 刘兴男; 时振刚; 莫逆
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2022-06-07

Abstract

The utility model provides a thrust disc subassembly with fluting structure, including the stator that two groups interval set up, rotor and thrust disc 2, rotor 4 locates between two sets of stators, thrust disc 2 fixed mounting is on rotor 4, and radially extend along rotor 4, each group's stator includes first stator 1 and second stator 3, first stator 1 and second stator 3 distribute in thrust disc 2's both sides along rotor 4's axial, and leave working gap with two terminal surfaces of thrust disc 2, evenly be equipped with a plurality of slot 5 along its radial extension on every terminal surface of thrust disc 2. Through a plurality of slots 5 of design on thrust disc 2 terminal surface, be favorable to the gas flow in the working gap between stator and the thrust disc 2, take away more heats, effectively reduce the temperature of stator and thrust disc 2. In addition, the present disclosure also provides a magnetic suspension bearing with a thrust disc with a slotted structure.

Description

Thrust disc assembly with slotting structure and magnetic suspension bearing

Technical Field

The disclosure relates to the technical field of bearings, in particular to a thrust disc assembly with a slotted structure and a magnetic suspension bearing.

Background

The magnetic suspension bearing suspends the rotor in the air by utilizing the magnetic force action, so that the rotor is not in mechanical contact with the stator. Compared with the traditional rolling bearing, sliding bearing and oil film bearing, the magnetic bearing has no mechanical contact, the rotor can run to a very high rotating speed, and the magnetic bearing has the advantages of small mechanical wear, low energy consumption, low noise, long service life, no lubrication, no oil pollution and the like, and is particularly suitable for special environments such as high speed, vacuum, ultra-clean and the like.

The electromagnetic bearing utilizes electromagnetic force to suspend the rotor, and can be divided into an axial electromagnetic bearing and a radial electromagnetic bearing according to the acting force direction. The axial electromagnetic bearing is generally composed of a stator and a thrust disc, a slit is formed between end faces of the stator and the thrust disc when the axial electromagnetic bearing works, airflow in the slit flows outwards under the rotating action of the thrust disc, and certain heat can be taken away. However, in the prior art, the slit is narrow, the resistance is large, and the gas flow is limited, so that the temperature of the opposite end surfaces of the bearing stator and the thrust disc is high, and the problems of insulation material aging, structural deformation and the like are easily caused.

BRIEF SUMMARY OF THE PRESENT DISCLOSURE

The main object of the present disclosure is to provide a thrust disc assembly with a slot structure and a magnetic suspension bearing, which aim to solve at least some of the above problems.

In order to achieve the above object, the present disclosure provides a thrust disc assembly with a slot structure, including two sets of stators, a rotor and a thrust disc which are arranged at intervals, wherein the rotor is arranged between the two sets of stators, the thrust disc is fixedly mounted on the rotor and extends along the radial direction of the rotor, each stator includes a first stator and a second stator, the first stator and the second stator are distributed on two sides of the thrust disc along the axial direction of the rotor and leave working gaps with two end faces of the thrust disc, and a plurality of grooves extending along the radial direction of the thrust disc are uniformly arranged on each end face of the thrust disc.

Optionally, the number M of trenches satisfies the following condition: n/50 < M ≦ 2, wherein M is an integer and N is the circumference of the inner bore of the stator.

Optionally, the ratio of the depth of the trench to the cross-sectional width of the trench is 1: 2.

Optionally, the depth of the groove ranges from 1mm to 2mm, and the cross-sectional width of the groove ranges from 2mm to 4 mm.

Optionally, the groove extends from the inner bore of the stator at a line projected on the thrust disc end face to an edge of the thrust disc.

Alternatively, the grooves extend linearly on the end face of the thrust disk, and the grooves are arranged obliquely in a direction opposite to the rotation direction of the thrust disk.

Optionally, the inclination angle of the grooves is 10 to 30 degrees.

Optionally, the groove extends curvilinearly on the end face of the thrust disc.

Optionally, the curve includes an involute, the groove is based on a projection line of an inner hole of the stator, and an involute direction of the groove is opposite to a rotation direction of the thrust disc.

In addition, in order to achieve the above object, the present disclosure also provides a magnetic suspension bearing with a thrust disc having a slotted structure, which includes the thrust disc assembly having a slotted structure as described in any one of the above.

The utility model provides a thrust disc subassembly with fluting structure, including the stator that two groups intervals set up, rotor and thrust disc, the rotor is located between two sets of stators, thrust disc fixed mounting is on the rotor, and radially extend along the rotor, each group's stator includes first stator and second stator, first stator and second stator distribute in the both sides of thrust disc along the axial of rotor, and leave working clearance with two terminal surfaces of thrust disc, evenly be equipped with a plurality of slots that extend along its radial on every terminal surface of thrust disc. Through a plurality of grooves of design on the thrust disc terminal surface, be favorable to the gaseous flow in the working clearance between stator and the thrust disc, take away more heats, effectively reduce the temperature of stator and thrust disc.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural view of one embodiment of a thrust disc assembly having a slotted configuration provided by the present disclosure;

FIG. 2 is a schematic view of a structure in which grooves on a thrust disc extend in a straight line and are inclined to the right;

FIG. 3 is a schematic structural view of grooves on the thrust plate extending linearly and inclined to the left;

FIG. 4 is a schematic structural view of a groove on the thrust disc extending in a curved manner and being bent to the right;

fig. 5 is a schematic structural diagram of grooves on the thrust disc extending in a curve and arranged in a leftward bending mode.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				1	First stator	4	Rotor
2	Thrust disc	5	Groove
				3	Second stator	6	Inner hole projection line

The objects, features, and advantages of the present disclosure will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

It should be noted that, if directional indication is referred to in the embodiments of the present disclosure, the directional indication is only used to explain a relative positional relationship, a motion situation, and the like between components in a certain posture, and if the certain posture is changed, the directional indication is changed accordingly.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present disclosure, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B", including either A or B or both A and B. Also, the technical solutions in the embodiments can be combined with each other, but must be based on the realization of the technical solutions by those skilled in the art, and when the technical solutions are contradictory or can not be realized, the combination of the technical solutions should be considered to be absent and not be within the protection scope of the present disclosure.

Referring to fig. 1, a thrust disc assembly having a slotted configuration includes a stator, a rotor 4, and a thrust disc 2. The stators comprise two groups, the two groups of stators are arranged side by side, and certain gaps are reserved between the two groups of stators. The rotor 4, which may also be called a rotor shaft, is movably arranged between two sets of stators. The stators are also provided with electromagnetic mechanisms which attract the rotor 4 by generating controllable electromagnetic force, and the rotor 4 is suspended between the two groups of stators under a certain state without contacting with any stator, so that a suspended bearing can be formed. Each group of stators comprises a first stator 1 and a second stator 3, the first stator 1 and the second stator 3 are arranged along the axial direction of the rotor 4, and a gap is left between the first stator 1 and the second stator 3. The thrust disc 2 is connected with the rotor 4 through interference fit and extends along the radial direction of the rotor 4 until the thrust disc 2 extends to a gap between the first stator 1 and the second stator 3, and the shape of the thrust disc 2 is close to that of a thin disc with equal thickness.

In the present embodiment, a working gap is left between the first stator 1 and the second stator 3 and the two end surfaces of the thrust disk 2, and during the rotation of the thrust disk 2 along with the rotor 4, the gas in the working gap is subjected to the centrifugal action of the rotation of the thrust disk 2, and flows from the inside to the outside. In the conventional structure, in order to make the entire structure more compact, the widths of the working gaps between the first stator 1 and the second stator 3 and both end surfaces of the thrust disk 2 are generally smaller than 1 mm. Therefore, the width of the working gap is too small, and the thrust disc 2 rotates at a high speed, so that the gas flow resistance in the working gap is large, the gas flow is not smooth enough, the heat between the two end faces of the first stator 1 and the second stator 3 and the thrust disc 2 is difficult to dissipate, the temperature between the stator and the thrust disc 2 is high, and the problems of aging of an insulating material, structural deformation and the like in a bearing can be easily caused.

In order to overcome this problem, in the present disclosure, a certain number of grooves 5 with a certain cross-sectional size, a certain length and a certain shape are processed on two end faces of the thrust disc 2, and the grooves 5 are distributed in a radial shape. Because the end face of the thrust disc 2 is provided with the grooves 5, when the thrust disc 2 rotates, air in the working gap can be guided by the grooves 5, so that the air can flow from the inner side to the outer side more easily, namely, the air flow in the working gap between the stator and the thrust disc 2 in the axial magnetic bearing is enhanced, more heat can be taken away, the temperature of the stator and the thrust disc 2 in the axial magnetic bearing can be effectively reduced, and the problems of insulating material aging, structural deformation and the like can be avoided.

In order to optimize the cooling effect, it may be necessary to perform a large number of experiments on the number, shape, and extending direction of the grooves 5 to obtain an optimal embodiment. Wherein the number of the grooves 5 on each end surface is at least two; if the number of the grooves 5 is smaller than two, and only one of the grooves 5 is provided, the grooves 5 cannot be uniformly distributed on the end surface of the thrust disc 2, and when the thrust disc 2 rotates at a high speed, the thrust disc 2 is dynamically unbalanced, and the overall balance of the bearing is damaged. In addition, the number of the grooves 5 is too small, and the heat dissipation effect is not significant. The number of trenches 5 must therefore be greater than or equal to two.

In the present embodiment, the number of grooves 5 on each end face of the thrust disc 2 is rounded up to "N/50", i.e. greater than "N/50", see FIG. 1, where N is the circumference of the inner bore of the stator in the axial magnetic bearing, in mm. According to experiments, if the number of the grooves 5 on the end face of the thrust disc 2 is less than N/50', the cooling and heat dissipation effects on the thrust disc 2 and the stator are not obvious.

In the present embodiment, the depth of the grooves 5 on the end face of the thrust disc 2 and the cross-sectional width of the grooves 5 both have an influence on the cooling and heat dissipation effects. But also the ratio between the depth of the grooves 5 and the cross-sectional width of the grooves 5 has an effect on the cooling and heat dissipation effect. Since the width of the groove 5 and the cooling heat dissipation effect are positively correlated, if the ratio between the depth of the groove 5 and the cross-sectional width of the groove 5 is greater than 1/2, the depth of the groove 5 is relatively deep. However, too deep a depth of the grooves 5 weakens the strength of the end faces of the thrust disk 2, which may risk breaking the thrust disk 2 during high speed rotation of the thrust disk 2. Meanwhile, if the ratio between the depth of the groove 5 and the cross-sectional width of the groove 5 is less than 1/2, the groove 5 will be shallow and wide, which will not significantly promote the gas flow in the working gap between the stator and the thrust disk 2, i.e. the cooling and heat dissipation effects of the thrust disk 2 and the stator will not be significant. Therefore, in the present embodiment, the ratio between the depth of the groove 5 and the cross-sectional width of the groove 5 is 1/2, and the cooling and heat dissipation effects are most significant, and the rigidity of the thrust disk 2 is not affected.

In the embodiment, the depth range of the groove 5 is 1mm-2mm and the section width range of the groove 5 is 2mm-4mm by integrating a plurality of factors such as cooling and heat dissipation effects, the rigidity of the thrust disc 2, the processing cost and the like.

In the present embodiment, the thrust disk 2 has an outer shape close to that of an equal-thickness thin disk, but in order to allow the thrust disk 2 to be attached to the rotor 4, a circular hole is formed in the center of the thrust disk 2, and the size of the circular hole is adapted to the axial diameter of the rotor 4.

In addition, the thrust disk is thick in the middle and thin around, so that there will be a small outer diameter and a large outer diameter at the end face of the thrust disk. Since the grooves 5 on the end face of the thrust disk 2 are mainly machined by a milling cutter, special attention is paid to the milling of the grooves 5. Therefore, the starting point of the slot cannot be too close to the center, which is prone to damage to small outer diameters.

In the present disclosure, the groove 5 includes two extension ways, one is a straight extension and the other is a curved extension. The two can both play the best effect of cooling heat dissipation under different operating conditions. The linear grooves 5 are suitable for the thrust disc 2 to operate at a medium-low speed, namely, when the rotating speed is less than 10000 r/min, the gas between the stator and the thrust disc 2 flows more smoothly along the linear grooves, and the cooling and heat dissipation effects are more obvious. In addition, the curved groove 5 is suitable for the thrust disc 2 when the thrust disc runs at a high speed, that is, when the rotating speed is more than 10000 r/min, the gas between the stator and the thrust disc 2 can flow out along the curved groove 5 quickly, and the cooling and heat dissipation effects are very obvious. Next, the grooves of the two kinds of extending shapes will be described in detail.

In the present embodiment, the grooves 5 may extend linearly on the end surface of the thrust disk 2, and in order to optimize the cooling and heat dissipation effect, the grooves 5 need to be arranged obliquely, and the direction in which the grooves 5 are inclined needs to be opposite to the direction in which the thrust disk 2 rotates. Specifically, referring to fig. 2 and 3, that is, if the thrust disk 2 rotates clockwise, the grooves 5 are inclined to the right; if the thrust disc 2 is rotated counterclockwise, the grooves 5 are inclined to the left. When the thrust disc 2 rotates, the gas in the working gap between the stator and the thrust disc 2 flows out along the grooves 5 opposite to the rotation direction of the thrust disc 2. It should be noted that, through continuous tests, it is found that the cooling and heat dissipation effect of the groove 5 is the best in the interval of 10 degrees to 30 degrees, and the heat between the stator and the thrust disc 2 in the axial magnetic bearing can be effectively dissipated, so as to reduce the temperature between the stator and the thrust disc 2 in the axial magnetic bearing.

Specifically, referring to fig. 2 and 3, 6 linear grooves 5 are formed on both end surfaces of the thrust disk 2. The diameter of the inner hole of the stator is 90mm, the number of the grooves 5 is rounded upwards according to N/50, wherein N is the circumference of the inner hole of the stator. The depth of the groove 5 is 1.5mm, the width of the groove 5 is 3mm, and the ratio of the depth of the groove 5 to the width of the groove 5 is 1: 2. In fig. 2 and 3, the inner bore projection line 6 represents a projection line of the inner bore of the stator on the end face of the thrust disc 2, and the starting point of the groove 5 extends from the inner bore projection line 6 to the edge of the thrust disc 2. The angle 5 indicates that the linear groove 5 is rotated by a certain angle around the intersection point of the groove 5 and the inner bore projection line 6, and it should be noted that the rotation is 20 ° in the present embodiment, and the rotation direction is opposite to the rotation direction of the thrust disc 2. The straight grooves 5 shown in this embodiment are uniformly distributed in a radial shape on each end face, and the distribution is completely uniform on both end faces.

In another embodiment, the grooves 5 extend in a curve on the end face of the thrust disk 2, the specific form of the curve being illustrated in the present disclosure as an involute. When the groove 5 is an involute curve, the groove 5 takes a projection line 6 of an inner hole of the stator as a base circle, and the involute direction of the groove 5 is opposite to the rotation direction of the thrust disc 2.

Referring specifically to fig. 4 and 5, 6 curved grooves 5 are formed on both end surfaces of the thrust disk 2. In this example the diameter of the stator bore is 90mm and the number of grooves 5 is rounded up to "N/50", where N is the circumference of the stator bore. The depth of the groove 5 is 1.5mm, the width of the groove 5 is 3mm, and the ratio of the depth of the groove 5 to the width of the groove 5 is 1: 2. In fig. 4 and 5, the projection line 6 of the inner hole of the stator represents the projection line of the inner hole of the stator on the end surface of the thrust disc 2, and the starting point of the groove 5 extends from the projection line 6 of the inner hole to the edge of the thrust disc 2. In the present embodiment, the line shape of the groove 5 is an involute curve, which uses the projection line of the stator inner hole on the end surface of the thrust disc 2 as a base circle, that is, the projection line 6 of the inner hole as a base circle, and the involute direction is opposite to the rotation direction of the thrust disc 2. The involute grooves 5 shown in the embodiment are uniformly distributed in a radial shape on each end face, and the grooves 5 on the two end faces of the thrust disc are completely distributed uniformly.

The above-mentioned embodiments are intended to illustrate the objects, aspects and advantages of the present disclosure in further detail, and it should be understood that the above-mentioned embodiments are only illustrative of the present disclosure and are not intended to limit the present disclosure, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure. Finally, it should be noted that: the above examples are only intended to illustrate the technical solutions of the present disclosure, not to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present disclosure.

Claims

1. A thrust disc assembly with a slotted structure is characterized in that the thrust disc assembly with the slotted structure comprises two groups of stators, a rotor (4) and a thrust disc (2) which are arranged at intervals, the rotor (4) is arranged between the two groups of stators, the thrust disc (2) is fixedly arranged on the rotor (4) and extends along the radial direction of the rotor (4), each stator comprises a first stator (1) and a second stator (3), the first stator (1) and the second stator (3) are distributed on two sides of the thrust disc (2) along the axial direction of the rotor (4), and working gaps are reserved between the first stator (1) and the second stator (3) and two end faces of the thrust disc (2);

wherein, a plurality of grooves (5) extending along the radial direction are uniformly arranged on each end surface of the thrust disc (2).

2. Thrust disc assembly with grooved structure according to claim 1, characterized in that the number M of grooves (5) satisfies the following condition: m is more than N/50, and M is more than or equal to 2, wherein M is an integer, and N represents the perimeter of the inner hole of the stator.

3. A disc thrust unit with grooved structure according to claim 1, characterized in that the ratio of the depth of the groove (5) to the cross-sectional width of the groove (5) is 1: 2.

4. A disc thrust assembly having a grooved structure according to claim 3, wherein the grooves (5) have a depth in the range of 1mm to 2mm and the grooves (5) have a cross-sectional width in the range of 2mm to 4 mm.

5. A disc thrust assembly with a slotted structure according to claim 1, characterised in that the slots (5) extend from the inner bore of the stator at the line of projection on the end face of the thrust disc (2) to the edge of the thrust disc (2).

6. A thrust disc assembly with a grooved structure according to claim 5, characterized in that the grooves (5) extend in a straight line on the end face of the thrust disc (2) and in that the grooves (5) are inclined in a direction opposite to the direction of rotation of the thrust disc (2).

7. The disc thrust plate assembly with grooved structure according to claim 6, characterized in that the grooves (5) are inclined at an angle of 10 to 30 degrees.

8. A disc thrust assembly with a slotted structure according to claim 5, characterised in that said grooves (5) extend curvilinearly on the end face of the thrust disc (2).

9. A disc thrust assembly with a slotted structure according to claim 8, wherein said curve comprises an involute, said slot (5) being based on the projection of the inner bore of said stator, the involute of said slot (5) being directed in the opposite direction to the rotation of said disc thrust (2).

10. A magnetic suspension bearing with a thrust disk of slotted configuration, characterized in that it comprises a thrust disk assembly of slotted configuration according to any of claims 1 to 9.