CN211018526U

CN211018526U - Motor rotating shaft and magnetic suspension motor

Info

Publication number: CN211018526U
Application number: CN201922442292.5U
Authority: CN
Inventors: 胡余生; 陈彬; 张小波; 张芳; 李广海; 龚高; 熊博文; 王飞; 李欣; 邓明星
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-07-14
Anticipated expiration: 2029-12-27

Abstract

The application provides a motor rotating shaft and a magnetic suspension motor. This motor shaft includes preceding minor axis (1), back minor axis (2), preceding magnetic suspension bearing (3), back magnetic suspension bearing (4), magnet steel (5) and sheath (6), preceding magnetic suspension bearing (3) cover is established in the front on minor axis (1), back magnetic suspension bearing (4) cover is established on back minor axis (2), sheath (6) cover is established in the front on minor axis (1) and back minor axis (2), magnet steel (5) cover is established in sheath (6), and be located between preceding minor axis (1) and the back minor axis (2), preceding minor axis (1) and/or back minor axis (2) adopt magnetic conduction material, first axial clearance (7) have between magnet steel (5) and preceding minor axis (1), and/or, second axial clearance (8) have between magnet steel (5) and the back minor axis (2). According to the motor rotating shaft, the magnetic suspension bearing output force can be increased while the interference of the magnetic steel ring magnetic field to the magnetic suspension bearing magnetic field is effectively avoided.

Description

Motor rotating shaft and magnetic suspension motor

Technical Field

The application relates to the technical field of motors, in particular to a motor rotating shaft and a magnetic suspension motor.

Background

The high-speed permanent magnet synchronous motor has the advantages of high power density, good dynamic response, simple structure and the like, and becomes one of the research hotspots in the international electrotechnical field. However, the permanent magnet in the rotor is generally made of a sintered neodymium iron boron permanent magnet material, and because the permanent magnet material is compressive and non-tensile, in order to ensure that the permanent magnet has sufficient strength at a high speed, a high-strength rotor sheath is generally wrapped outside the permanent magnet, and the rotor sheath and the permanent magnet are in interference fit to ensure that the permanent magnet still bears a certain compressive stress when in work, so that the safe operation of a high-speed motor is ensured.

The prior art provides a surface-mounted high-speed permanent magnet motor rotor structure, which adopts a three-section annular magnetic steel ring structure design, wherein a magnetic conducting core is made of a magnetic conducting material, and a rotating shaft end part at two ends are made of a non-magnetic conducting material, so that an axial magnetic circuit is blocked, and axial magnetic leakage is reduced.

The design of the three sections of shafts has the disadvantages that the front short shaft and the rear short shaft can only use non-magnetic conductive materials, and if the annular magnetic steel rings made of the magnetic conductive materials are used, magnetic leakage magnetic paths can be formed in the axial direction, so that the magnetic fields of the magnetic suspension bearings at the two ends of the rotating shaft are interfered, the control difficulty of the magnetic suspension bearings is increased, and the control precision of the magnetic suspension bearings is reduced; and the front short shaft and the rear short shaft use non-magnetic-conductive materials to limit the magnetic circuit of the magnetic suspension bearing, so that the magnetic circuit of the rotor of the magnetic suspension bearing is easily saturated, and the bearing output is reduced.

SUMMERY OF THE UTILITY MODEL

Therefore, the technical problem to be solved by the application is to provide a motor rotating shaft and a magnetic suspension motor, which can effectively avoid the interference of a magnetic steel ring magnetic field to a magnetic suspension bearing magnetic field and increase the output force of the magnetic suspension bearing.

In order to solve the above problems, the present application provides a motor rotating shaft, which includes a front short shaft, a rear short shaft, a front magnetic suspension bearing, a rear magnetic suspension bearing, a magnetic steel and a sheath, wherein the front short shaft and the rear short shaft are axially arranged at intervals, the front magnetic suspension bearing is sleeved on the front short shaft, the rear magnetic suspension bearing is sleeved on the rear short shaft, the sheath is sleeved on the front short shaft and the rear short shaft, the magnetic steel sleeve is arranged in the sheath and is located between the front short shaft and the rear short shaft, the front short shaft and/or the rear short shaft is made of a magnetic conductive material, a first axial gap is formed between the magnetic steel and the front short shaft, and/or a second axial gap is formed between the.

Preferably, the magnetic steel is a columnar solid structure.

Preferably, one end of the inner peripheral side of the sheath close to the front short shaft is provided with a stopping bulge, and the stopping bulge is positioned in the first axial gap; or one end of the inner circumference side of the sheath, which is close to the rear short shaft, is provided with a stopping bulge, and the stopping bulge is positioned in the second axial gap.

Preferably, the stop projection is an annular projection.

Preferably, the axial thickness of the first axial gap and/or the second axial gap is 8-15 mm.

Preferably, the front stub shaft comprises a first axial projection projecting towards the sheath, the first axial projection being housed inside the sheath; and/or the rear stub shaft comprises a second axial projection projecting towards the sheath, the second axial projection being nested within the sheath.

Preferably, the sheath is shrink fit with the front stub shaft, the magnetic steel and the rear stub shaft.

Preferably, one end face of the magnetic steel is provided with a magnetizing positioning groove passing through the center of a circle, the magnetizing positioning groove radially penetrates through the magnetic steel, and the magnetizing direction of the magnetic steel is perpendicular to or parallel to the extending direction of the magnetizing positioning groove.

Preferably, the end of the front short shaft is provided with a magnetizing positioning mark, and the positioning direction of the magnetizing positioning mark is parallel to or perpendicular to the extending direction of the magnetizing positioning groove.

According to another aspect of the present application, there is provided a magnetic levitation motor, comprising a motor shaft as described above.

The application provides a motor shaft, including preceding minor axis, the back minor axis, preceding magnetic suspension bearing, back magnetic suspension bearing, magnet steel and sheath, preceding minor axis and back minor axis axial interval set up, preceding magnetic suspension bearing cover is established in the front on the minor axis, back magnetic suspension bearing cover is established on the minor axis in the back, the sheath cover is established in preceding minor axis and back minor axis, the magnet steel bushing is established in the sheath, and be located between preceding minor axis and the back minor axis, preceding minor axis and/or back minor axis adopt magnetic conductive material, first axial clearance has between magnet steel and the preceding minor axis, and/or, second axial clearance has between magnet steel and the back minor axis. The motor rotating shaft forms an axial gap between at least one end of the magnetic steel and the short shaft made of the magnetic conductive material, therefore, the axial magnetic circuit of the magnetic steel can be blocked by utilizing the axial gap, the axial magnetic leakage of the magnetic steel is reduced, the magnetic leakage magnetic circuit formed by the magnetic steel in the axial direction is effectively avoided, meanwhile, the axial gap can effectively limit the axial magnetic flux leakage of the magnetic steel, so that the front short shaft and the rear short shaft can be made of magnetic conductive materials, the magnetic force lines of a large amount of magnetic steel can not reach the magnetic suspension bearing through the front short shaft and the rear short shaft to cause large interference to the magnetic field of the magnetic suspension bearing, the control precision and the control difficulty of the magnetic suspension bearing are reduced, the front short shaft and the rear short shaft are made of magnetic conductive materials, so that the magnetic circuit area of the magnetic suspension bearing can be increased, the magnetic circuit of a rotor of the magnetic suspension bearing is not easy to saturate, the bearing output is effectively improved, and the working performance of the magnetic suspension bearing is improved.

Drawings

Fig. 1 is a sectional structural view of a motor rotating shaft according to an embodiment of the present application;

fig. 2 is a schematic magnetic circuit diagram of a magnetic suspension bearing of a motor rotating shaft according to an embodiment of the present application.

The reference numerals are represented as:

1. a front minor axis; 2. a rear minor axis; 3. a front magnetic suspension bearing; 4. a rear magnetic suspension bearing; 5. magnetic steel; 6. a sheath; 7. a first axial gap; 8. a second axial gap; 9. a stop projection; 10. a first axial projection; 11. the second axial direction is convex.

Detailed Description

Referring to fig. 1 to 2 in combination, according to an embodiment of the present application, a motor rotating shaft includes a front short shaft 1, a rear short shaft 2, a front magnetic suspension bearing 3, a rear magnetic suspension bearing 4, a magnetic steel 5, and a sheath 6, where the front short shaft 1 and the rear short shaft 2 are axially spaced, the front magnetic suspension bearing 3 is sleeved on the front short shaft 1, the rear magnetic suspension bearing 4 is sleeved on the rear short shaft 2, the sheath 6 is sleeved on the front short shaft 1 and the rear short shaft 2, the magnetic steel 5 is sleeved in the sheath 6 and is located between the front short shaft 1 and the rear short shaft 2, the front short shaft 1 and/or the rear short shaft 2 are made of a magnetic conductive material, a first axial gap 7 is provided between the magnetic steel 5 and the front short shaft 1, and/or a second axial gap 8 is provided between the magnetic steel.

The motor rotating shaft forms an axial gap between at least one end of the magnetic steel 5 and the short shaft made of the magnetic conductive material, so that the axial gap can be utilized to block the axial magnetic circuit of the magnetic steel 5, the axial magnetic flux leakage of the magnetic steel 5 is reduced, the magnetic flux leakage magnetic circuit formed by the magnetic steel 5 in the axial direction is effectively avoided, meanwhile, the axial gap can effectively limit the axial magnetic flux leakage of the magnetic steel 5, the front short shaft 1 and the rear short shaft 2 are made of the magnetic conductive material, the magnetic force lines of a large amount of the magnetic steel 5 can not reach the magnetic suspension bearing through the front short shaft 1 and the rear short shaft 2 to form large interference on the magnetic field of the magnetic suspension bearing, the control precision and the control difficulty of the magnetic suspension bearing are reduced, the front short shaft 1 and the rear short shaft 2 are made of the magnetic conductive material, the magnetic circuit area of the magnetic suspension, the working performance of the magnetic suspension bearing is improved.

Preferably, in this embodiment, a first axial gap 7 is formed between the first end of the magnetic steel 5 and the front short shaft 1, and a second axial gap 8 is formed between the magnetic steel 5 and the rear short shaft 2, so that sufficient axial gaps are formed between the magnetic steel 5 and the front short shaft 1 and the rear short shaft 2, and magnetic lines of force of the magnetic steel 5 can be effectively prevented from reaching the magnetic suspension bearing through the front short shaft 1 and the rear short shaft 2, so as to interfere with the magnetic field of the magnetic suspension bearing, reduce the control difficulty of the magnetic suspension bearing, and improve the control accuracy of the magnetic suspension bearing.

Due to the existence of the two axial gaps, the front short shaft 1 and the rear short shaft 2 can be made of magnetic conductive materials, so that the magnetic circuit areas of the front magnetic suspension bearing 3 and the rear magnetic suspension bearing 4 can be effectively increased, the magnetic circuit of the magnetic suspension bearing rotor is not easy to saturate, the bearing output is effectively improved, and the working performance of the magnetic suspension bearing is improved.

Through verification, when the front short shaft 1 and the rear short shaft 2 are made of magnetic conductive materials, the output of the front magnetic suspension bearing 3 and the output of the rear magnetic suspension bearing 4 are increased by more than 50%, and the effect is obviously improved.

Preferably, the magnetic steel 5 is a columnar solid structure. Magnet steel 5 adopts cylindric solid construction, can increase magnet steel 5's power of exerting oneself, can save the dabber structure that passes magnet steel 5 simultaneously, make the axial gap who avoids the magnetic leakage that forms between the minor axis at magnet steel 5 and both ends become possible, can adopt succinct structure to realize the optimization to magnet steel 5 axial magnetic leakage, minor axis 1 leads the magnetized while with back minor axis 2 before realizing, can not increase motor shaft's the design degree of difficulty, and the design cost is reduced, make motor shaft's structure easily realize more.

The magnetic steel 5 can also be annular magnetic steel as long as a mandrel is not arranged in a central hole of the annular magnetic steel.

One end of the inner peripheral side of the sheath 6 near the front short shaft 1 is provided with a stopper projection 9, and the stopper projection 9 is located in the first axial gap 7. Through setting up backstop arch 9, can inject the axial mounted position of magnet steel 5 in sheath 6, guarantee that magnet steel 5 can fix in place in sheath 6. The stopper projection 9 may be formed integrally with the sheath 6 or may be formed separately from the sheath 6 and then fitted into the sheath 6.

One end of the inner peripheral side of the sheath 6 close to the rear short shaft 2 is provided with a stopper projection 9, and the stopper projection 9 is positioned in the second axial gap 8.

Preferably, the stop projection 9 is an annular projection.

The axial thickness of the first axial gap 7 and/or the second axial gap 8 is 8-15 mm, the width of the axial gap can be ensured to be enough to play an effective magnetic isolation effect, and the magnetic steel 5 is effectively prevented from generating axial magnetic leakage.

The front stub shaft 1 comprises a first axial projection 10 projecting towards the sheath 6, the first axial projection 10 being housed inside the sheath 6.

The rear stub shaft 2 comprises a second axial projection 11 projecting towards the sheath 6, the second axial projection 11 fitting inside the sheath 6.

By arranging the first axial bulge 10 and the second axial bulge 11, the sleeve connection and matching between the sheath 6 and the front short shaft 1 and the rear short shaft 2 can be conveniently realized.

Sheath 6 and preceding minor axis 1, magnet steel 5 and the cooperation of back minor axis 2 heat jacket can utilize sheath 6 further to fix a position the axial position of magnet steel 5, guarantee the installation fixed between sheath 6 and preceding minor axis 1 and the back minor axis 2 simultaneously.

One end face of the magnetic steel 5 is provided with a magnetizing positioning groove passing through the circle center, the magnetizing positioning groove radially penetrates through the magnetic steel 5, and the magnetizing direction of the magnetic steel 5 is perpendicular to or parallel to the extending direction of the magnetizing positioning groove.

The end part of the front short shaft 1 is provided with a magnetizing positioning mark, and the positioning direction of the magnetizing positioning mark is parallel to or vertical to the extending direction of the magnetizing positioning groove. The magnetizing positioning mark is, for example, a groove which is arranged on the end surface of the front short shaft 1 and extends along the radial direction of the front short shaft 1, or two positioning holes which are arranged at two ends of the front short shaft 1 with the same diameter, and the center lines of the two positioning holes can be perpendicular to or parallel to the extending direction of the magnetizing positioning groove, so that the magnetizing direction of the magnetic steel 5 can be accurately positioned. A magnetizing positioning mark may also be provided on the rear stub shaft 2.

Through the mode, the magnetizing direction of the magnetic steel 5 can be conveniently determined, so that the accuracy of the magnetizing direction of the magnetic steel 5 is ensured when the motor rotating shaft is wholly magnetized in the final stage.

The sheath 6 is made of a high-strength non-magnetic material, such as an alloy sheath. The alloy sheath can be made of nickel-based alloy, titanium alloy and the like, and is in interference fit with the front short shaft, the rear short shaft and the magnetic steel 5, and the alloy sheath can transmit mechanical torque between different components of the rotating shaft in a connection mode; when the motor rotates at a high speed, the alloy sheath also plays a role in protection, and the safe operation of the motor rotating shaft is ensured.

The first end of the sheath 6 is attached to the axial positioning end face of the front short shaft 1, and the second end is attached to the axial positioning end face of the rear short shaft 2.

During assembly, the solid magnetic steel 5 is positioned firstly, namely the hot-pressing equipment mechanical arm is sleeved in the alloy sheath 6 in a hot mode, and the axial position of the magnetic steel 5 is clamped through the annular protrusion in the alloy sheath 6 so as to ensure that the assembly is error-free. The front short shaft 1 is positioned after the assembly is finished, the matching relation between the magnetizing positioning mark on the front short shaft 1 and the magnetizing positioning groove on the magnetic steel 5 needs to be ensured, then the alloy sheath 6 heated to a certain temperature is hot-installed on the front short shaft 1, and then the rear short shaft 2 is rapidly placed in the alloy sheath 6. And the subsequent rear short shaft 2 can be smoothly installed to a preset position to be attached to the end face of the sheath 6. Due to the existence of the annular bulge, the end face of the magnetic steel 5 is tightly attached to the annular bulge, so that an air gap is formed in the rotating shaft. In a similar way, the other end is compressed tightly with the sheath 6 owing to the terminal surface of back minor axis 2, also forms air gap between back minor axis 2 and magnet steel 5, and air permeability can be ignored to prevent motor axial magnetic leakage, promoted motor efficiency. And after the hot sleeve is finished, the rotating shaft is compacted and cooled for a period of time, and the rotating shaft is assembled.

And finally, magnetizing the rotating shaft according to the magnetizing positioning mark of the front short shaft 1 to complete the magnetizing of the solid magnetic steel 5.

According to the embodiment of the application, the magnetic suspension motor comprises a motor rotating shaft which is the motor rotating shaft.

It is readily understood by a person skilled in the art that the advantageous ways described above can be freely combined, superimposed without conflict.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed. The foregoing is only a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present application, and these modifications and variations should also be considered as the protection scope of the present application.

Claims

1. The utility model provides a motor rotating shaft, its characterized in that, includes preceding minor axis (1), back minor axis (2), preceding magnetic suspension bearing (3), back magnetic suspension bearing (4), magnet steel (5) and sheath (6), preceding minor axis (1) with back minor axis (2) axial interval sets up, preceding magnetic suspension bearing (3) cover is established on preceding minor axis (1), back magnetic suspension bearing (4) cover is established on back minor axis (2), sheath (6) cover is established preceding minor axis (1) with back minor axis (2) is gone up, magnet steel (5) cover is established in sheath (6), and is located preceding minor axis (1) with between back minor axis (2), preceding minor axis (1) and/or back minor axis (2) adopt magnetic conductive material, magnet steel (5) with first axial clearance (7) have between preceding minor axis (1), and/or a second axial gap (8) is formed between the magnetic steel (5) and the rear short shaft (2).

2. The rotating shaft of an electric machine according to claim 1, characterized in that the magnetic steel (5) is a cylindrical solid structure.

3. The machine spindle according to claim 1, characterized in that one end of the inner peripheral side of the sheath (6) close to the front stub shaft (1) is provided with a stop protrusion (9), the stop protrusion (9) being located in the first axial gap (7); or one end of the inner peripheral side of the sheath (6) close to the rear short shaft (2) is provided with a stopping protrusion (9), and the stopping protrusion (9) is positioned in the second axial gap (8).

4. A motor shaft according to claim 3, characterised in that the stop projection (9) is an annular projection.

5. The machine shaft according to claim 1, characterized in that the axial thickness of the first axial gap (7) and/or the second axial gap (8) is 8-15 mm.

6. The machine spindle according to claim 1, characterized in that the front stub shaft (1) comprises a first axial projection (10) projecting towards the sheath (6), the first axial projection (10) being housed inside the sheath (6); and/or the rear stub shaft (2) comprises a second axial projection (11) projecting towards the sheath (6), the second axial projection (11) being nested within the sheath (6).

7. Motor shaft according to claim 1, characterised in that said sheath (6) is shrink-fitted to said front stub shaft (1), said magnetic steel (5) and said rear stub shaft (2).

8. The rotating shaft of the motor according to claim 2, wherein a magnetizing positioning groove passing through a center of a circle is formed in one end surface of the magnetic steel (5), the magnetizing positioning groove radially penetrates through the magnetic steel (5), and a magnetizing direction of the magnetic steel (5) is perpendicular to or parallel to an extending direction of the magnetizing positioning groove.

9. The motor rotating shaft according to claim 8, wherein the end of the front short shaft (1) is provided with a magnetizing positioning mark, and the positioning direction of the magnetizing positioning mark is parallel to or perpendicular to the extending direction of the magnetizing positioning groove.

10. A magnetic levitation motor comprising a motor shaft, wherein the motor shaft is as claimed in any one of claims 1 to 9.