Rotor structure, motor and centrifuge having the same

Abstract

The present application provides a rotor structure comprising a rotating shaft and a magnet, wherein the magnet is sleeved around the rotating shaft; the rotating shaft includes a magnetic isolation region; the rotating shaft includes a first region and a second region sequentially arranged along the central axis of the rotating shaft, with the magnetic isolation region disposed on the first region; the position of the magnetic isolation region corresponds to the position of the magnetic poles of the magnet. The rotor structure of the present application can alter the flow of magnetic lines of force, thereby improving the rotor's resistance to demagnetization and enhancing the motor's resistance to demagnetization.

Description

Technical Field

[0001] The present application belongs to the technical field of centrifuges, and in particular relates to a rotor structure, a motor, and a centrifuge having the same. Background Art

[0002] At present, high-speed rotor structures have difficulty in dissipating heat due to their small size, high power density, and high loss density. This may even cause the local temperature of the rotor structure to be too high, thereby causing irreversible demagnetization of the permanent magnet, especially when running at high speeds.

[0003] However, in the prior art, most of the methods for enhancing the anti-demagnetization capability of the rotor structure are complex in structure and difficult to implement.

[0004] Therefore, how to provide a rotor structure with a simple structure and easy implementation to enhance the anti-demagnetization ability of the rotor structure and a motor having the same has become a problem that technicians in this field urgently need to solve. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present application is to provide a rotor structure, a motor and a centrifuge having the same, which can enhance the anti-demagnetization ability of the motor and have a simple structure and are easy to implement.

[0006] In order to solve the above problems, the present application provides a rotor structure, including a rotating shaft and a magnet, which is sleeved outside the rotating shaft; the rotating shaft includes a first area and a second area arranged in sequence in the direction of the central axis of the rotating shaft, and a magnetic isolation area is provided on the first area; the magnetic isolation area is located on the outer peripheral side of the rotating shaft; the position of the magnetic isolation area corresponds to the magnetic pole position of the magnet.

[0007] Preferably, the magnetic isolation area includes a magnetic isolation groove; the magnetic isolation groove is opened on the side wall of the rotating shaft; the position of the magnetic isolation groove corresponds to the position of the magnetic pole of the magnet.

[0008] Preferably, the magnetic isolation groove is filled with magnetic isolation material.

[0009] Preferably, the magnetic isolation groove extends along the axial direction of the rotating shaft; the first end of the magnetic isolation groove corresponds to the first end of the magnetic steel; the second end of the magnetic isolation groove corresponds to the second end of the magnetic steel;

[0010] And / or, the contour line of the inner wall of the magnetic isolation groove on the cross section of the rotating shaft is arc-shaped.

[0011] Preferably, the number of magnetic poles is set to at least two.

[0012] Preferably, the number of magnetic isolation regions is equal to the number of magnetic poles; and the magnetic isolation regions and magnetic poles are arranged in a one-to-one correspondence.

[0013] Preferably, the magnetic isolation groove is a curved groove.

[0014] Preferably, the chord length of the arc is L1; the arc height of the arc is H; wherein H <L1。

[0015] Preferably, the magnetic steel includes an N-pole region and an S-pole region; the N-pole region and the S-pole region are arranged at intervals in the circumferential direction around the rotating shaft.

[0016] Preferably, on the cross section of the rotating shaft, the arc length of the rotating shaft contour line corresponding to a single S-pole region or N-pole region is L; the arc length of the magnetic isolation groove corresponding to the S-pole region or N-pole region is 15% to 37% of L; and / or, the cross-sectional area of ​​a single S-pole region or N-pole region is S; the cross-sectional area of ​​the magnetic isolation region corresponding to the S-pole region or N-pole region is 3% to 35% of S.

[0017] According to another aspect of the present application, a motor is provided, including a rotor structure, which is the above-mentioned rotor structure.

[0018] According to another aspect of the present application, a centrifuge is provided, including a rotor motor, which is the above-mentioned motor.

[0019] The rotor structure, motor and centrifuge provided in the present application are provided with a magnetic isolation area on the rotating shaft. The magnetic isolation area corresponds to the position of the magnetic pole. By changing the trend of the magnetic lines of force here, the anti-demagnetization ability of the rotor is improved, and the anti-demagnetization ability of the motor can be enhanced. The structure is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of the rotor structure of an embodiment of the present application;

[0021] Figure 2 This is a schematic structural diagram of the rotor structure of the comparative example of this application;

[0022] Figure 3 This is a diagram showing the demagnetization simulation results of the rotor structure of the comparative example of this application;

[0023] Figure 4 This is a diagram showing the demagnetization simulation results of the rotor structure of Example 1 of the present application;

[0024] Figure 5 This is a diagram showing the demagnetization simulation results of the rotor structure of Example 2 of the present application;

[0025] Figure 6 This is a diagram of the demagnetization simulation results of the rotor structure of Example 3 of the present application.

[0026] The reference numerals indicate:

[0027] 1. Rotating shaft; 2. Magnet; 3. Magnetic isolation area. DETAILED DESCRIPTION

[0028] See also Figure 1As shown, according to an embodiment of the present application, a motor includes a rotating shaft 1 and a magnet 2, and the magnet 2 is sleeved on the outside of the rotating shaft 1; the rotating shaft 1 includes a magnetic isolation area 3; the rotating shaft 1 includes a first area and a second area arranged in sequence in the direction of the central axis of the rotating shaft 1, and the magnetic isolation area 3 is provided on the first area; the position of the magnetic isolation area 3 corresponds to the magnetic pole position of the magnet 2, and the magnetic isolation area is provided on the rotating shaft, and the magnetic isolation area corresponds to the magnetic pole position. By changing the trend of the magnetic lines of force here, the anti-demagnetization ability of the rotor is improved, and the anti-demagnetization ability of the motor can be enhanced, and the structure is simple and easy to implement.

[0029] Furthermore, the magnetic isolation area 3 includes a magnetic isolation groove; the magnetic isolation groove is opened on the side wall of the rotating shaft 1; the position of the magnetic isolation groove corresponds to the position of the magnetic pole of the magnet 2.

[0030] Furthermore, the magnetic isolation groove is filled with magnetic isolation material, which can not only change the trend of the magnetic lines of force here, thereby improving the anti-demagnetization ability of the rotor, but also does not affect the strength of the rotor.

[0031] Furthermore, the magnetic isolation groove extends along the axial direction of the rotating shaft 1; the first end of the magnetic isolation groove corresponds to the first end of the magnetic steel 2; the second end of the magnetic isolation groove corresponds to the second end of the magnetic steel 2;

[0032] And / or, the contour line of the inner wall of the magnetic isolation groove on the cross section of the rotating shaft 1 is arc-shaped.

[0033] Further, the number of magnetic poles is set to at least two.

[0034] Furthermore, the number of the magnetic isolation regions 3 is equal to the number of the magnetic poles; and the magnetic isolation regions 3 are arranged in a one-to-one correspondence with the magnetic poles.

[0035] Furthermore, the magnetic isolation groove is a curved groove.

[0036] Furthermore, the chord length of the arc is L1; the arc height of the arc is H; where H <L1。

[0037] Furthermore, the magnetic steel 2 includes an N-pole region and an S-pole region; the N-pole region and the S-pole region are arranged at intervals in the circumferential direction around the rotating shaft 1 .

[0038] Furthermore, on the cross section of the rotating shaft 1, the arc length of the contour line of the rotating shaft 1 corresponding to a single S-pole region or N-pole region is L (the contour line of the rotating shaft 1 without slots); the arc length of the magnetic isolation groove corresponding to the S-pole region or N-pole region is 15% to 37% of L; and / or, the cross-sectional area of ​​a single S-pole region or N-pole region is S; the cross-sectional area of ​​the magnetic isolation region 3 corresponding to the S-pole region or N-pole region is 3% to 35% of S. Within this numerical range, not only can the trend of the magnetic lines of force here be changed, thereby improving the rotor's anti-demagnetization ability, but also the strength of the rotor will not be affected.

[0039] Example 1

[0040] 38UH magnetic steel is used; a magnetic isolation groove is opened on the shaft, and the size of the magnetic isolation groove is:

[0041] The chord length corresponding to the magnetic isolation groove is 11.1 mm, the distance between the chord of the magnetic isolation groove and the central axis of the rotating shaft is 23.4 mm, the arc height corresponding to the magnetic isolation groove is 3.4 mm, the cross-sectional area of ​​the S pole region corresponding to the magnetic isolation groove is 30.8 mm2, and the cross-sectional area of ​​the magnetic isolation groove accounts for 3.4% of the cross-sectional area of ​​the S pole region. The arc length of the contour line of the rotating shaft 1 corresponding to the S pole region is 11.2 mm, and the magnetic isolation groove accounts for 15% of the contour line of the rotating shaft 1 in the cross section.

[0042] Example 2

[0043] Using 38UH magnetic steel;

[0044] 38UH magnetic steel is used; a magnetic isolation groove is opened on the shaft, and the size of the magnetic isolation groove is:

[0045] The chord length corresponding to the magnetic isolation groove is 15.9 mm, the distance between the chord of the magnetic isolation groove and the central axis of the rotating shaft is 22.6 mm, the arc height corresponding to the magnetic isolation groove is 2.5 mm, the cross-sectional area of ​​the S pole region corresponding to the magnetic isolation groove is 41.9 mm2, and the cross-sectional area of ​​the magnetic isolation groove accounts for 4.6% of the cross-sectional area of ​​the S pole region. The arc length of the contour line of the rotating shaft 1 corresponding to the S pole region is 16.3 mm, and the magnetic isolation groove accounts for 21.5% of the contour line of the rotating shaft 1 in the cross section.

[0046] like Figure 5 , which is a schematic diagram of the demagnetization simulation results of Example 2.

[0047] Example 3

[0048] 38UH magnetic steel is used; a magnetic isolation groove is opened on the shaft, and the size of the magnetic isolation groove is:

[0049] The chord length corresponding to the magnetic isolation groove is 19.8 mm, the distance between the chord of the magnetic isolation groove and the central axis of the rotating shaft is 21.9 mm, the arc height corresponding to the magnetic isolation groove is 1.6 mm, the cross-sectional area of ​​the S pole region corresponding to the magnetic isolation groove is 50.4 mm2, and the cross-sectional area of ​​the magnetic isolation groove accounts for 5.6% of the cross-sectional area of ​​the S pole region. The arc length of the contour line of the rotating shaft 1 corresponding to the S pole region is 20.4 mm, and the contour line of the magnetic isolation groove on the cross section accounts for 27.1% of the contour line of the rotating shaft 1.

[0050] like Figure 6 , which is a schematic diagram of the demagnetization simulation results of Example 1.

[0051] Comparative Example

[0052] Combine Figure 2 As shown in FIG, the comparative example uses 38UH magnets; no magnetic isolation area is set on the shaft. Figure 3 As shown, it is a schematic diagram of the demagnetization simulation results of the comparative example.

[0053] According to an embodiment of the present application, a motor includes a rotor structure, which is the above-mentioned rotor structure.

[0054] According to an embodiment of the present application, a centrifuge includes a motor, which is the motor described above.

[0055] Furthermore, the centrifuge is a 100KW military magnetic levitation centrifuge.

[0056] See also Figure 3-6 As shown in the figure, the horizontal axis is the demagnetization current multiple, and the vertical axis is the minimum magnetic flux density along the magnetization direction on a representative reference line in the initial demagnetization area of ​​the magnetic steel. For the same brand of magnetic steel at the same temperature, when the minimum magnetic flux density is lower than a certain fixed value, it can be determined that the magnetic steel has been demagnetized. Figure 3-6 The magnetic steels of Examples 1-3 and the comparative example are all 38UH. The demagnetization reference value of this grade of magnetic steel at 130°C is -0.2T, so -0.2T is used as a reference when comparing the simulation analysis results.

[0057] See also Figure 3-6 It can be seen from the demagnetization simulation results in that, through Examples 1-3 of the present application, a magnetic isolation area 3 is set at a position corresponding to each magnetic pole on the rotating shaft 1, which can improve the anti-demagnetization ability of the surface-mounted high-speed rotor structure; and the size of the magnetic isolation groove can directly affect the magnetic isolation material to improve the anti-demagnetization ability of the rotor structure.

[0058] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0059] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application. The above are merely preferred embodiments of the present application. It should be noted that those skilled in the art may make various improvements and variations without departing from the technical principles of the present application, and such improvements and variations shall also be considered within the scope of protection of the present application.

Claims

1. A rotor structure, characterized in that: The invention comprises a rotating shaft (1) and a magnetic steel (2), wherein the magnetic steel (2) is sleeved outside the rotating shaft (1); the rotating shaft (1) comprises a first region and a second region sequentially arranged in the direction of the central axis of the rotating shaft (1), and a magnetic isolation region (3) is arranged on the first region; the magnetic isolation region (3) is located on the outer peripheral side of the rotating shaft (1); the position of the magnetic isolation region (3) corresponds to the position of the magnetic pole of the magnetic steel (2); the magnetic steel (2) comprises an N-pole region and an S-pole region; the N-pole region and the S-pole region are arranged at intervals in the circumferential direction around the rotating shaft (1); the number of the magnetic poles is set to at least two; On the cross section of the rotating shaft (1), the arc length of the contour line of the rotating shaft (1) corresponding to a single S-pole region or N-pole region is L; the magnetic isolation region (3) includes a magnetic isolation groove, and the arc length of the magnetic isolation groove corresponding to the S-pole region or N-pole region is 15% to 37% of L; and / or, the cross-sectional area of ​​a single S-pole region or N-pole region is S; the cross-sectional area of ​​the magnetic isolation region (3) corresponding to the S-pole region or N-pole region is 3% to 35% of S.

2. The rotor structure according to claim 1, characterized in that: The magnetic isolation groove is provided on the side wall of the rotating shaft (1); the position of the magnetic isolation groove corresponds to the position of the magnetic pole of the magnetic steel (2).

3. The rotor structure according to claim 1, characterized in that: The magnetic isolation groove is filled with magnetic isolation material.

4. The rotor structure according to any one of claims 2 or 3, characterized in that: The magnetic isolation groove extends along the axial direction of the rotating shaft (1); the first end of the magnetic isolation groove corresponds to the first end of the magnetic steel (2); the second end of the magnetic isolation groove corresponds to the second end of the magnetic steel (2); And / or, the contour line of the inner wall of the magnetic isolation groove on the cross section of the rotating shaft (1) is arc-shaped.

5. The rotor structure according to claim 1, characterized in that: The number of the magnetic isolation regions (3) is equal to the number of the magnetic poles; and the magnetic isolation regions (3) are arranged in a one-to-one correspondence with the magnetic poles.

6. The rotor structure according to claim 2, characterized in that: The magnetic isolation groove is a curved groove.

7. The rotor structure according to claim 4, characterized in that: The chord length of the arc is L1; the arc height of the arc is H; where H <L1。 8. A motor comprising a rotor structure, wherein the rotor structure is the rotor structure according to any one of claims 1 to 7.

9. A centrifuge comprising a motor, wherein the motor is the motor according to claim 8.

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