Permanent magnet harmonic gear transmission device based on flexible neodymium iron boron

Abstract

The invention discloses a permanent magnet harmonic gear transmission device based on flexible neodymium iron boron. The permanent magnet harmonic gear transmission device comprises a shell, a permanent magnet harmonic gear and an output flange. The shell comprises a shell end cover and a stator shell, the shell end cover is fixed to the upper portion of the stator shell through a second bolt, and the permanent magnet harmonic gear is installed in the shell. The permanent magnet harmonic gear comprises a high-speed rotating shaft, a high-speed rotating shaft sleeve, an oval structure wave generator, a flexible gear, a flexible neodymium iron boron permanent magnet ring and a stator permanent magnet ring. According to the device, magnetic field modulation is conducted through periodic changes of the air gap length to achieve torque output, a magnetic field adjusting ring structure in a coaxial magnetic field modulation type magnetic gear is abandoned, the device has the advantages of being small in loss, high in transmission efficiency, large in transmission ratio and torque density and the like, and compared with the coaxial magnetic field modulation type magnetic gear, higher input rotating speed can be used; pure magnetic non-contact coaxial variable-speed transmission is achieved, and mechanical hard contact is avoided.

Description

Technical Field

[0001] The present invention relates to the field of magnetic transmission technology, and in particular to a permanent magnetic harmonic gear transmission device based on flexible NdFeB. Background Art

[0002] Traditional mechanical gears are widely used in industrial transmission, but due to rigid contact, there are problems of mechanical wear and high maintenance costs. Magnetic gears have great potential in low-speed and high-torque application scenarios due to their characteristics of no lubrication, low noise, low maintenance, and automatic overload protection.

[0003] At present, high torque density magnetic gears mainly rely on the principle of magnetic field modulation to realize their functions. For coaxial magnetic gears that use magnetic field modulation rings, there are certain limitations on their transmission ratio. Too high a rotation ratio increases the overall volume, resulting in a significant decrease in torque density. In addition, since the iron loss in the magnetic ring increases with the increase in speed, the speed of this magnetic gear should not be too fast. In contrast, permanent magnet harmonic gears achieve magnetic field modulation through periodic changes in the air gap length, and do not require the modulation effect of magnetic rings, thereby reducing the structural volume. The output wheel has a low speed, which reduces the energy loss and improves the transmission efficiency. With the increase in the number of stator permanent magnet pole pairs and the permanent magnet harmonic gear, the transmission ratio and torque density can be effectively improved.

[0004] In order to meet the requirements of small volume, high transmission ratio, large output torque and high torque density, permanent magnetic harmonic gears can be used. It is also possible to connect multiple magnetic harmonic gears in series to form multi-stage magnetic harmonic gears. Selecting appropriate multi-stage parallel magnetic harmonic gears can further increase the transmission ratio. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention discloses a permanent magnet harmonic gear transmission device based on flexible NdFeB, comprising:

[0006] Housing, permanent magnet harmonic gear, output flange;

[0007] The housing comprises a housing end cover and a stator housing, the housing end cover is fixed to the upper part of the stator housing by a second bolt, and the permanent magnet harmonic gear is installed in the housing;

[0008] The permanent magnet harmonic gear comprises a high-speed rotating shaft, a high-speed rotating shaft sleeve, an elliptical structural wave generator, a flexible wheel, a flexible NdFeB permanent magnet ring and a stator permanent magnet ring;

[0009] The stator permanent magnet ring is mounted on the inner circumferential surface of the stator housing; the stator permanent magnet ring includes a plurality of stator permanent magnets, the flexible NdFeB permanent magnet is mounted on the elliptical surface of the flexible wheel, and a non-uniform air gap is formed between the flexible NdFeB permanent magnet and the stator permanent magnet; the high-speed rotating shaft is movably mounted on the housing end cover; the elliptical structural wave generator is mounted on the high-speed rotating shaft and connected via a flat key; the high-speed rotating shaft sleeve is mounted on the high-speed rotating shaft and is located below the elliptical structural wave generator;

[0010] The lower end of the stator housing is fixedly connected with a first bearing, and the output flange is installed on the upper part of the first bearing.

[0011] Furthermore, assuming that the number of magnetic pole pairs of the stator permanent magnet ring of the permanent magnet harmonic gear is P1, the number of magnetic pole pairs of the flexible NdFeB permanent magnet ring is P2, and the number of sinusoidal periods of the non-uniform air gap is P w , then the following relationship is satisfied: P1=P w +P2.

[0012] Furthermore, a non-uniform air gap is provided between the stator permanent magnet ring and the flexible NdFeB permanent magnet ring.

[0013] Furthermore, in terms of axial length, the axial length of the stator permanent magnet ring is consistent with the axial length of the flexible NdFeB permanent magnet ring.

[0014] Furthermore, a plurality of the stator permanent magnets are evenly adhered to the inner circumferential surface of the stator housing, and the magnetic poles of adjacent stator permanent magnets are opposite; the flexible NdFeB permanent magnet ring includes a plurality of the flexible permanent magnets, and the plurality of flexible permanent magnets are evenly adhered to the elliptical surface of the flexible wheel, and the magnetic poles of adjacent flexible permanent magnets are opposite.

[0015] Furthermore, the rotation speed of the output flange is determined by the interaction between the stator permanent magnet of the permanent magnet harmonic gear and the flexible permanent magnet outside the flexible wheel, which is specifically expressed as: where ω h is the angular velocity of the high-speed rotating shaft.

[0016] Furthermore, the transmission ratio G of the permanent magnet harmonic gear is r It is expressed as:

[0017] Furthermore, the output flange and the first bearing are interference fit via conical pins; the first bearing is fixed via a fourth bolt, and the first bearing is a cross roller bearing.

[0018] Furthermore, a second bearing is installed between the output flange and the high-speed rotating shaft; a third bearing is installed between the high-speed rotating shaft and the housing end cover; the second bearing and the third bearing are both deep groove ball bearings.

[0019] Furthermore, a plurality of the permanent magnet harmonic gears are connected in series to form a multi-stage permanent magnet harmonic gear, and a suitable multi-stage series permanent magnet harmonic gear is selected to increase the transmission ratio.

[0020] Due to the adoption of the above-mentioned technical scheme, the present invention provides a permanent magnet harmonic gear transmission device based on flexible NdFeB, which utilizes the periodic change of air gap length to modulate the magnetic field to achieve torque output, and abandons the magnetic modulation ring structure in the coaxial magnetic field modulation type magnetic gear. It has the advantages of low loss, high transmission efficiency, large transmission ratio and torque density. Compared with the coaxial magnetic field modulation type magnetic gear, it can use a higher input speed to achieve pure magnetic contactless coaxial speed change transmission, avoid mechanical hard contact, small maintenance workload, high reliability, low noise, and smaller size and high torque density than the coaxial magnetic field modulation type magnetic gear. It has the advantages of compact structure, high transmission ratio, high transmission efficiency, high torque density, high reliability, maintenance-free, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the connection relationship of the permanent magnet harmonic gear transmission device of the present invention.

[0023] Figure 2 It is a schematic diagram of the coordination between the stator permanent magnet ring and the rotor permanent magnet ring of the present invention.

[0024] Figure 3 It is a schematic structural diagram of the flexible wheel of the present invention.

[0025] Figure 4 It is a schematic structural diagram of the high-speed rotating shaft of the present invention.

[0026] Figure 5 It is a schematic structural diagram of the output flange of the present invention.

[0027] In the figure: 1. output flange; 2. conical pin; 3. first bearing; 4. second bearing; 5. first bolt; 6. flexible wheel; 7. stator housing; 8. flat key; 9. flexible NdFeB permanent magnet ring; 10. second bolt; 11. third bearing; 12. housing end cover; 13. elliptical structural wave generator; 14. fourth bearing; 15. first sleeve; 16. non-uniform air gap; 17. stator permanent magnet ring; 18. fifth bearing; 19. high-speed rotating shaft; 20. high-speed rotating shaft sleeve; 21. third bolt; 22. fourth bolt. DETAILED DESCRIPTION

[0028] In order to make the technical solutions and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention:

[0029] like Figure 1 The purpose of the permanent magnet harmonic gear transmission device based on flexible NdFeB shown in the figure is to avoid the problems of permanent magnet peeling and crushing caused by hard contact of rigid permanent magnets due to deformation of flexible wheel when rigid permanent magnets are fixed on the flexible wheel by using flexible NdFeB permanent magnets. A permanent magnet harmonic gear transmission device based on flexible NdFeB permanent magnets is developed to improve the problems of centrifugal vibration, structural eccentricity and high maintenance cost of cycloid magnetic gears during operation.

[0030] like Figures 1 to 5As shown, the present invention provides a permanent magnet harmonic gear transmission device based on flexible NdFeB, which mainly includes a housing, a permanent magnet harmonic gear device, and an output flange; the housing is used to provide an installation space, and the permanent magnet harmonic gear device and the output flange are installed in the housing; the housing includes a housing end cover 12 and a stator housing 7, and the housing end cover 12 is connected to the stator housing 7 by a second bolt 10; the permanent magnet harmonic gear device includes a high-speed rotating shaft 18, an elliptical structural wave generator 13, a flat key 8, a fourth bearing 14, a first sleeve 15, fifth bearing 18, flexible wheel 6, flexible NdFeB permanent magnet ring 9, second sleeve 20, first bearing 4, third bearing 11; high-speed rotating shaft 18 is rotatably mounted in the third bearing 11, and the third bearing 11 is mounted inside the housing end cover 12 through clearance fit; stator permanent magnet ring 17 is mounted on the inner circumferential surface of the stator housing 7, and the stator permanent magnet ring includes a plurality of stator permanent magnets, and the plurality of stator permanent magnets are evenly pasted on the inner circumferential surface of the stator housing with opposite polarities; flexible NdFeB permanent magnet ring 9 Installed on the outer surface of the flexible wheel 6, the flexible NdFeB permanent magnet ring includes multiple flexible NdFeB permanent magnets, and multiple flexible NdFeB permanent magnets are evenly pasted on the outer circumferential surface of the flexible wheel. The polarities of adjacent flexible NdFeB permanent magnets are opposite. At this time, the flexible NdFeB permanent magnets can be called surface-mounted NS poles with alternating intervals; the elliptical wave generator 13 is assembled with the flexible wheel 6 through the fourth bearing, the first sleeve 15 and the fifth bearing 18, so that a non-uniform air gap 16 is formed between the stator permanent magnet ring 17 and the flexible NdFeB permanent magnet ring 9; the flexible wheel 6 is threadedly connected to the output flange 1 through the first bolt 5, so that the flexible wheel 6 can be fixed on the output flange 1; a second sleeve 20 is installed between the elliptical structural wave generator 13 and the second bearing 4 installed inside the output flange 1 to limit the displacement of the elliptical structural wave generator 13; the output flange 1 is installed inside the first bearing 3 through the fourth type of bolt 22, and is connected and fixed by the conical pin 2 and the fourth bolt 22, and the outer ring of the first bearing 3 is threadedly connected to the stator housing 7 through the third bolt 21. In actual applications, when used as a reducer, the high-speed rotating shaft 19 is connected to an external power source, and the output flange 1 is connected to a load source. It should be noted that the rotation speed of the high-speed rotating shaft 19 is higher than the rotation speed of the output flange 1.

[0031] The working principle of the patent of the present invention is as follows: Specifically, taking the transmission when used as a reducer as an example, the high-speed rotating shaft 19 of the present invention is movably connected with the shell end cover 12, and rotates with the axis of the high-speed rotating shaft 19 as the rotation center under the action of the external driving force. At this time, the driving force is transmitted to the elliptical structural wave generator 13 through the flat key 8, and the elliptical structural wave generator 13 drives the flexible wheel 6 through the fourth bearing 14 and the fifth bearing 18, so that a non-uniform air gap 16 is formed between the flexible NdFeB permanent magnet ring and the stator permanent magnet ring (the non-uniform air gap 16 refers to the air gap with different thicknesses at various locations in the circumferential direction of the flexible NdFeB permanent magnet ring 9 and the stator permanent magnet ring 17), and the driving force generated by the stator permanent magnet ring 17 and the flexible NdFeB permanent magnet ring 9 through the non-uniform air gap 16 is transmitted to the load through the output flange 1.

[0032] Specifically, taking the transmission when used as a reducer as an example, the high-speed rotating shaft 19 of the present invention is movably connected with the housing, and rotates with the axis of the high-speed rotating shaft 19 as the rotation center under the action of the external driving force. The output flange 1 includes an output shaft for outputting torque and torque to the load; the elliptical structural wave generator 13 is fixed to the high-speed rotating shaft 19 through a key connection, and a second sleeve is installed between the high-speed rotating shaft 19 and the second bearing to prevent the elliptical structural wave generator 13 from axial displacement; the stator permanent magnet ring 17 is installed on the inner circumferential surface of the stator housing 7. When the high-speed rotating shaft 19 is externally driven, the flexible NdFeB permanent magnet ring 9 on the outer circumferential surface of the flexible wheel 6 is driven to rotate through the elliptical structural wave generator 13. At this time, the distribution of the non-uniform air gap 19 changes with the rotation of the elliptical structural wave generator 13 and the flexible wheel 6 (the rotation direction of the non-uniform air gap 19 is opposite to the rotation direction of the flexible wheel 6 and the elliptical structural wave generator 13).

[0033] like Figure 1 and Figure 2 As described above, in implementation, the stator permanent magnet ring and the rotor permanent magnet ring of the present invention can adopt a variety of magnetization methods, such as radial magnetization, parallel magnetization, sinusoidal magnetization and concentrated magnetization. As a further preferred embodiment, the number of pole pairs of the stator permanent magnet ring of the present invention is two more than the number of pole pairs of the rotor permanent magnet ring.

[0034] In order to improve the service life of the present invention, Figure 1 As shown, a third bearing 11 is installed between the housing end cover 12 and the high-speed rotating shaft 19 of the present invention, a second bearing 4 is installed between the high-speed rotating shaft 19 and the output flange 1; a first sleeve 15 is installed between the fourth bearing 14 and the fifth bearing 18, which can effectively prevent the bearings from moving with the vibration of the mechanism.

[0035] In order to limit the displacement of the elliptical wave generator structure, a high-speed rotating shaft sleeve is installed between the high-speed rotating shaft and the elliptical structure wave generator to limit the displacement of the elliptical structure wave generator.

[0036] In order to maximize the torque transmission, the number of stator permanent magnet pole pairs P1 of the permanent magnet harmonic gear device and the number of flexible permanent magnet pole pairs P2 on the flexible wheel should satisfy the following relationship:

[0037] P1=P2+P w (1)

[0038] Among them, P w is the number of sinusoidal cycles generated by the air gap of the harmonic magnetic gear. In this description, P w The value is 2. The rotation speed of the output shaft is determined by the interaction between the stator permanent magnet and the flexible permanent magnet of the harmonic magnetic gear, which can be expressed as:

[0039]

[0040] Among them, ω h is the angular velocity of the high-speed rotating shaft.

[0041] Combining equations (1) and (2), we can get the transmission ratio G of the permanent magnet harmonic gear: r , which can be expressed as:

[0042]

[0043] It can be seen from the above formula that if you want to adjust the output transmission ratio of the harmonic magnetic gear of the present invention, you only need to change the number of stator permanent magnet pole pairs P1 and the number of sinusoidal periods P generated by the air gap of the harmonic magnetic gear. w The number of pole pairs P2 of the flexible permanent magnet on the flexible wheel can be adjusted.

[0044] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A permanent magnet harmonic gear transmission device based on flexible NdFeB, characterized in that: include: Housing, permanent magnet harmonic gear, output flange; The housing comprises a housing end cover and a stator housing, the housing end cover is fixed to the upper part of the stator housing by a second bolt, and the permanent magnet harmonic gear is installed in the housing; The permanent magnet harmonic gear comprises a high-speed rotating shaft, a high-speed rotating shaft sleeve, an elliptical structural wave generator, a flexible wheel, a flexible NdFeB permanent magnet ring and a stator permanent magnet ring; The stator permanent magnet ring is mounted on the inner circumferential surface of the stator housing; the stator permanent magnet ring includes a plurality of stator permanent magnets, the flexible NdFeB permanent magnet is mounted on the elliptical surface of the flexible wheel, and a non-uniform air gap is formed between the flexible NdFeB permanent magnet and the stator permanent magnet; the high-speed rotating shaft is movably mounted on the housing end cover; the elliptical structural wave generator is mounted on the high-speed rotating shaft and connected via a flat key; the high-speed rotating shaft sleeve is mounted on the high-speed rotating shaft and is located below the elliptical structural wave generator; The lower end of the stator housing is fixedly connected with a first bearing, and the output flange is installed on the upper part of the first bearing.

2. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim is characterized in that: The number of magnetic pole pairs of the stator permanent magnet ring of the permanent magnet harmonic gear is P1, the number of magnetic pole pairs of the flexible NdFeB permanent magnet ring is P2, and the number of sinusoidal periods of the non-uniform air gap is P w , then the following relationship is satisfied: P1=P w +P2.

3. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 1 or 2, characterized in that: A non-uniform air gap is provided between the stator permanent magnet ring and the flexible NdFeB permanent magnet ring.

4. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 3 is characterized in that: In terms of axial length, the axial length of the stator permanent magnet ring is consistent with the axial length of the flexible NdFeB permanent magnet ring.

5. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 1 is characterized in that: Wherein, multiple stator permanent magnets are evenly adhered to the inner circumferential surface of the stator shell, and the magnetic poles of adjacent stator permanent magnets are opposite; the flexible NdFeB permanent magnet ring includes multiple flexible permanent magnets, and multiple flexible permanent magnets are evenly adhered to the elliptical surface of the flexible wheel, and the magnetic poles of adjacent flexible permanent magnets are opposite.

6. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 1 is characterized in that: The rotation speed of the output flange is determined by the interaction between the stator permanent magnet of the permanent magnet harmonic gear and the flexible permanent magnet outside the flexible wheel, which is specifically expressed as: where ω h is the angular velocity of the high-speed rotating shaft.

7. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 1 or 6, characterized in that: The transmission ratio G of the permanent magnet harmonic gear r It is expressed as:

8. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 7 is characterized in that: The output flange and the first bearing are interference-fitted via conical pins; the first bearing is fixed via a fourth bolt, and the first bearing is a cross roller bearing.

9. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 8, characterized in that: A second bearing is installed between the output flange and the high-speed rotating shaft; a third bearing is installed between the high-speed rotating shaft and the housing end cover; the second bearing and the third bearing are both deep groove ball bearings.

10. The flexible NdFeB permanent magnet harmonic gear transmission device according to claim 9, characterized in that: A plurality of the permanent magnet harmonic gears are connected in series to form a multi-stage permanent magnet harmonic gear, and a suitable multi-stage series permanent magnet harmonic gear is selected to increase the transmission ratio.

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