Coaxial magnetic gear of poly-magnetic type magnetic adjusting device with embedded permanent magnet

Abstract

The application relates to a coaxial magnetic gear of a magnetic concentration type magnetic adjusting device with embedded permanent magnets, which is composed of an outer rotor assembly, an inner rotor assembly and a magnetic adjusting device. The inner rotor permanent magnets adopt a traditional permanent magnet arrangement mode, the outer rotor permanent magnets adopt segmented one-way magnetization, and each pole pair permanent magnet is embedded in an outer rotor yoke iron, and the outer rotor yoke iron end is designed to be outwardly extended. The magnetic adjusting device is structurally changed from a traditional silicon steel sheet stacking structure into an integral columnar structure, the magnetic adjusting device material is selected to be industrial pure iron with higher relative magnetic permeability, the magnetic adjusting device adjusting column adopts a structure with a 1 / 2 period sine on the side and a trapezoidal section, and the magnetic adjusting device adopts two fixing methods of a closed type and a non-closed type. The application effectively enhances the torque density of the magnetic gear, so that the magnetic gear can be widely applied to a high torque working environment.

Description

TECHNICAL FIELD

[0001] The application relates to the field of transmission technology in mechanical engineering, and is a magnetic force gear of a non-contact type, in particular a coaxial magnetic force gear of a magnetic concentration type magnetic adjusting device with embedded permanent magnets. The magnetic force gear can be applied to a non-contact variable speed system of high torque and high and low speed transmission, and the magnetic adjusting device of the magnetic force gear has higher deformation resistance, so that the practical environment of the magnetic force gear is greatly improved compared with a traditional magnetic force gear, and the magnetic force gear can be applied to a higher temperature working environment. BACKGROUND

[0002] In industrial production, a mechanical gear is a traditional mechanical transmission device, transmission is completed through mutual meshing between gear teeth, and the mechanical gear is widely applied to various industrial fields such as national defense, agriculture and automobile manufacturing due to the advantages of fixed transmission ratio, wide applicable speed and load range and long service life. However, the normal operation of the mechanical gear requires mutual contact, and problems such as noise, high maintenance cost and serious aging inevitably exist, so that the application scene of the mechanical gear is limited, and the installation and maintenance of the transmission system are difficult. With the continuous development of new industries, the shortcomings of the traditional mechanical gear are more and more obvious. With the development of modern science and technology and the improvement of the performance of permanent magnet materials, many scholars have proposed a solution of using a magnetic force gear structure to replace the traditional mechanical gear.

[0003] The magnetic force gear is driven by magnetic coupling force, and the force and torque are transmitted without contact through the magnetic field coupling in the air gap. Compared with the traditional mechanical gear, the magnetic force gear has the advantages of non-contact transmission, overload protection and high transmission efficiency. The high-performance magnetic force gear introduces a magnetic adjusting pole piece, and the permanent magnets in the inner and outer rotors are modulated by the magnetic adjusting pole piece to generate a harmonic magnetic field with the same number of magnetic pole pairs as the rotor permanent magnet in the inner and outer air gaps, thereby improving the utilization rate of the permanent magnet and greatly increasing the transmission efficiency of the magnetic force gear.

[0004] A kind of air gap adjustable magnetic force gear applying side edge sine magnetic adjusting device is disclosed in Chinese invention patent 201710461909.0 of Jiangsu University, which applies the side edge sine structure of magnetic adjusting block on the cylinder type magnetic force gear, and the 1 / 2 period sine curve applied by the magnetic adjusting block is changed in the axial direction, and the modulation effect of the 1 / 2 period sine curve is different in the air gap adjustment process. The permanent magnet end adopts the traditional magnetizing method, and the leakage magnetic field of the permanent magnet end is not designed to have a structure for processing, which will generate more leakage magnetic field, so that the torque density provided by the magnetic force gear is not high enough, and the magnetic adjusting device adopts a laminated structure of silicon steel sheet, which is prone to deformation when the magnetic force gear is working, and the two aspects greatly reduce the application range of the magnetic force gear.

[0005] A disc type magnetic gear using a magnetic gathering type magnetic adjusting device is disclosed in Jiangsu University's Chinese invention patent 201911052924.5. The magnetic adjusting device is divided into a modulation part and a magnetic gathering part, which can reduce the magnetic leakage of the permanent magnet and improve the torque density during modulation. The structure is mainly suitable for disc type magnetic gears, mostly for occasions with low coaxiality requirements, and the magnetic adjusting device is connected by rivets, which increases the eddy current generated by the magnetic gear during work, resulting in high temperature and accelerating the demagnetization of the permanent magnet. The magnetic adjusting device has many parts, which reduces the stability of the magnetic gear, and the sharp corners of multiple parts are not treated accordingly, without considering the magnetic saturation effect of the sharp corners. SUMMARY

[0006] To overcome the defects of insufficient magnetic energy utilization of permanent magnets, permanent magnet end leakage, and the structure of the magnetic adjusting device that cannot meet the stress and temperature requirements during actual work, the outer rotor permanent magnet is embedded in the outer rotor yoke and uses a one-way magnetization segmented tight arrangement; the magnetic adjusting device part is replaced by a complete magnetic adjusting column instead of the traditional silicon steel sheet laminated magnetic adjusting block, the air gap between each magnetic adjusting column is equivalent to the epoxy resin part of the traditional magnetic adjusting device, the side of the magnetic adjusting column adopts a 1 / 2 period sine curve, the end of the magnetic adjusting column adopts a magnetic adjusting column end cover or a magnetic adjusting column pressing ring two fixing ways, and the corners of the side of the magnetic adjusting column, the magnetic adjusting column pressing ring and the two end face edges of the magnetic adjusting column end cover are all designed with round corners, and a coaxial magnetic gear with a permanent magnet embedded magnetic gathering type magnetic adjusting device is proposed.

[0007] A coaxial magnetic gear with a permanent magnet embedded magnetic gathering type magnetic adjusting device is composed of an outer rotor assembly, an inner rotor assembly and a magnetic adjusting device. The outer rotor assembly includes a driven shaft, an outer rotor yoke and an outer rotor permanent magnet, the outer rotor yoke is connected with the driven shaft by a key, the driven shaft is designed with a shaft shoulder for positioning, the inner part of the outer rotor yoke is hollow, and the inner wall is provided with a groove, and the permanent magnet is installed in the groove of the outer rotor yoke in a close arrangement manner. The inner rotor assembly includes a driving shaft, an inner rotor yoke and an inner rotor permanent magnet, the inner rotor yoke is connected with the driving shaft by a key, the driving shaft is also designed with a shaft shoulder for positioning, and the inner rotor permanent magnet is installed on the surface of the inner rotor yoke in a close arrangement manner. The magnetic adjusting device assembly includes a magnetic adjusting column pressing ring or a magnetic adjusting column end cover, a magnetic adjusting column and a magnetic adjusting column base, the magnetic adjusting device assembly is installed between the outer rotor assembly and the inner rotor assembly, the bottom end of the magnetic adjusting column is connected with the magnetic adjusting column base after cooperation, and the magnetic adjusting column pressing ring or the magnetic adjusting column end cover is connected with the top end of the magnetic adjusting column by welding, so as to fix the whole magnetic adjusting device. The number of magnetic adjusting columns is n s , the number of pole pairs of the inner rotor permanent magnet is P1, the number of pole pairs of the outer rotor permanent magnet is P2, and they satisfy the relationship: n s =P1+P2.

[0008] The axial soft magnetic material part of the magnetic adjusting column in the magnetic adjusting device realizes the modulation of the magnetic field by concentrating the magnetic induction lines, the magnetic adjusting column end cover of the sealed type soft magnetic material is used to replace the magnetic adjusting column pressing ring fixed at the top end of the magnetic adjusting column, the magnetic induction lines generated at the end of the permanent magnet are concentrated, the leakage magnetic of the end of the inner rotor permanent magnet is effectively weakened, a magnetic gathering type magnetic adjusting device is formed as a whole, the purpose of the magnetic field modulation and the torque density enhancement of the magnetic gear is achieved.

[0009] The present application also comprises: the expression of the side edge of the magnetic adjusting column being a 1 / 2 period sinusoidal curve is In the formula, A is the amplitude of the 1 / 2 period sinusoidal curve, H s is the radial thickness of the magnetic adjusting pole piece. When the magnetic adjusting column is processed, the value of A in the function can be changed to change the shape of the side edge to change the magnetic gathering effect of the magnetic adjusting column.

[0010] When the magnetic adjusting device is fixed in a non-closed mode, the magnetic adjusting device is composed of a magnetic adjusting column base, a magnetic adjusting column and a magnetic adjusting column pressing ring, the magnetic adjusting column base is installed in cooperation with the magnetic adjusting column, a groove is formed on one side of the magnetic adjusting column pressing ring in cooperation with the shape of the magnetic adjusting column, and then the magnetic adjusting column pressing ring is installed in cooperation with the magnetic adjusting column. The material of the magnetic adjusting column is DT4 industrial pure iron or No. 10 steel, the magnetic adjusting column base and the magnetic adjusting column pressing ring adopt non-magnetic materials with high strength such as stainless steel, and the connection mode adopts welding. When the magnetic adjusting device is fixed in a closed mode, the magnetic adjusting device is composed of a magnetic adjusting column base, a magnetic adjusting column and a magnetic adjusting column end cover, the installation mode is the same as that of the non-closed mode, the magnetic adjusting column end cover used in the closed mode can reduce the leakage magnetic of the end of the inner rotor permanent magnet and realize the axial magnetic gathering effect, the material of the magnetic adjusting column end cover and the magnetic adjusting column is DT4 industrial pure iron or No. 10 steel, and the manufacturing method adopts 3D printing technology or casting method. The outer rotor permanent magnet adopts embedded segmented type tight arrangement, three permanent magnets are used for one pole pair, and the magnetization direction adopts one-way magnetization, which can well suppress the magnetic loop formed between the adjacent permanent magnets of the outer rotor, thereby eliminating the magnetic flux between the outer rotor permanent magnets, improving the effective magnetic flux of the magnetic gear and enhancing the magnetic field strength of the working air gap of the magnetic gear.

[0011] The application has the following advantages: the magnetic adjusting device has two parts of magnetic adjusting and magnetic concentrating, and the embedded installation of permanent magnet and the arrangement of one-way magnetization are combined to realize the functions of magnetic adjusting and end magnetic concentrating. The whole columnar magnetic adjusting part is used to replace the traditional laminated silicon steel sheet to effectively improve the structural strength of the magnetic adjusting column device. The edges of the magnetic adjusting column, the pressing ring of the magnetic adjusting column and the two end faces of the end cover of the magnetic adjusting column are all rounded to greatly reduce the magnetic saturation phenomenon at the sharp corners during the operation of the magnetic gear. The embedded arrangement of the outer rotor permanent magnet and the one-way magnetization can reduce the end leakage of the permanent magnet and effectively reduce the self-induction loop between the permanent magnets of the adjacent two pole pairs of the outer rotor. When the non-closed magnetic adjusting device is used, the magnetic gear will not be deformed due to the excessive size of the magnetic adjusting column under the high torque working environment, the stability of the magnetic adjusting column is improved, the eddy current generated by the magnetic adjusting device is small, and the service life of the magnetic adjusting device is ensured. When the closed magnetic adjusting device is used, the end leakage of the inner rotor permanent magnet is reduced while the stability of the magnetic adjusting column is ensured, the utilization rate of the permanent magnet is effectively improved, and the magnetic gear is suitable for higher torque occasions. BRIEF DESCRIPTION OF DRAWINGS

[0012] The application will be further described below with reference to the drawings and embodiments

[0013] Figure 1 It is a schematic diagram of the assembly of the coaxial magnetic gear of the embedded magnetic concentrating type magnetic adjusting device.

[0014] Figure 2 It is a two-dimensional schematic diagram of the magnetization direction and installation position of the inner and outer rotor permanent magnets.

[0015] Figure 3 It is a 1 / 4 cross-sectional exploded view of the overall three-dimensional structure when the magnetic adjusting device is fixed in a non-closed manner.

[0016] Figure 4 It is a three-dimensional structure diagram of the magnetic adjusting device when the magnetic adjusting device is fixed in a non-closed manner.

[0017] Figure 5 It is a 1 / 4 cross-sectional exploded view of the overall three-dimensional structure when the magnetic adjusting device is fixed in a closed manner.

[0018] Figure 6 It is a three-dimensional structure diagram of the magnetic adjusting device when the magnetic adjusting device is fixed in a non-closed manner.

[0019] Figure 7 It is a three-dimensional structure diagram of the magnetic adjusting column of the magnetic adjusting device.

[0020] Figure 8 It is a three-dimensional structure diagram of the magnetic adjusting column base of the magnetic adjusting device.

[0021] Figure 9 This is a schematic diagram of the three-dimensional structure of the slotted yoke of the outer rotor in the embodiment.

[0022] Figure 10 (a) is a two-dimensional schematic diagram of the cross-section of the magnetic column in the embodiment.

[0023] Figure 10 (b) is a schematic diagram of the equivalent cross section of the magnetic column in the coordinate system in the embodiment.

[0024] Figure 10 (c) is the equivalent function curve of the side of the magnetic column in the embodiment.

[0025] When the adjusting column of the adjusting device is fixed in a non-enclosed manner: 1—Driven shaft 2—Outer rotor yoke 3—Outer rotor permanent magnet 4—Adjusting column pressure ring 5—Adjusting column 6—Adjusting column base 7—Inner rotor permanent magnet 8—Inner rotor yoke 9—Drive shaft 11—Outer rotor yoke groove.

[0026] When the magnetic adjustment column of the magnetic adjustment device is fixed in a closed manner: 1—Driven shaft 2—Outer rotor yoke 3—Outer rotor permanent magnet 5—Magnetic adjustment column 6—Magnetic adjustment column base 7—Inner rotor permanent magnet 8—Inner rotor yoke 9—Drive shaft 10—Magnetic adjustment column end cover 11—Outer rotor yoke groove. Detailed Implementation

[0027] like Figure 1 As shown, a coaxial magnetic gear with a permanent magnet embedded magnetic focusing type magnetic adjustment device consists of an outer rotor assembly III, an inner rotor assembly I, and a magnetic adjustment device assembly II.

[0028] The outer rotor assembly includes a driven shaft 1, an outer rotor yoke 3, and an outer rotor permanent magnet 4. The outer rotor yoke 3 is connected to the driven shaft via a key 2. The driven shaft 1 has a shoulder for positioning. The outer rotor yoke 3 has a hollowed-out structure with grooves 11 on its inner wall. The permanent magnets are installed face-to-face in the grooves inside the yoke, with three permanent magnets in each groove and zero gap between them. The inner rotor assembly includes a drive shaft 9, an inner rotor yoke 8, and an inner rotor permanent magnet 7. The inner rotor yoke 8 is connected to the drive shaft 9 via a key. The drive shaft 9 also has a shoulder for positioning. The inner rotor permanent magnet 7 is installed face-to-face on the side of the inner rotor yoke, with a close arrangement of the two magnets.

[0029] When the magnetic adjusting device is fixed in a non-closed mode by the magnetic adjusting column pressing ring 5, the magnetic adjusting device assembly includes the magnetic adjusting column pressing ring 5, the magnetic adjusting column 6 and the magnetic adjusting column base 7. The magnetic adjusting column 6 is connected with the magnetic adjusting column base 7 by welding. The magnetic adjusting column pressing ring 5 is provided with a slot with the same thickness as the magnetic adjusting column 6. The magnetic adjusting column pressing ring 5 is connected with the magnetic adjusting column 6 by welding after being matched. When working, the driving shaft 9 in the inner rotor assembly rotates, drives the inner rotor yoke 7 to rotate, and the inner rotor permanent magnet 8 generates a magnetic field. The magnetic field generated by the inner rotor assembly I is modulated by using the high magnetic permeability of the magnetic adjusting column 6. The modulated magnetic field interacts with the magnetic field generated by the outer rotor permanent magnet 3 on the outer rotor yoke 2, drives the outer rotor yoke 3 to rotate, and drives the driven shaft 1 in the outer rotor assembly III to rotate.

[0030] When the magnetic adjusting device is fixed in a closed mode by the magnetic adjusting column end cover 10, the magnetic adjusting device assembly includes the magnetic adjusting column 6, the magnetic adjusting column base 7 and the magnetic adjusting column end cover 10. The magnetic adjusting column 6 is connected with the magnetic adjusting column base 7 by welding. The magnetic adjusting column end cover 10 is provided with a slot with the same thickness as the magnetic adjusting column 6. The magnetic adjusting column end cover 10 is connected with the magnetic adjusting column 6 by welding after being matched. When working, the driving shaft 9 in the inner rotor assembly rotates, drives the inner rotor yoke 7 to rotate, and the inner rotor permanent magnet 8 generates a magnetic field. The magnetic field generated by the inner rotor assembly I is modulated by using the high magnetic permeability of the magnetic adjusting column 6. The modulated magnetic field interacts with the magnetic field generated by the outer rotor permanent magnet 3 on the outer rotor yoke 2, drives the outer rotor yoke 3 to rotate, and drives the driven shaft 1 in the outer rotor assembly III to rotate. Meanwhile, the material of the magnetic adjusting column end cover 10 is DT4 industrial pure iron, which has high magnetic permeability and suppresses the magnetic leakage at the end of the inner rotor permanent magnet 8, thereby enhancing the magnetic field density between the inner rotor assembly I and the outer rotor assembly III.

[0031] The side of the magnetic adjusting column 5 in the magnetic adjusting device adopts a 1 / 2 period sine curve structure, which effectively improves the modulation effect of the magnetic adjusting device on the magnetic field. The magnetic adjusting column 5 is made of DT4 industrial pure iron material as a whole. When the magnetic gear works, it can overcome a large radial force, thereby being not easy to deform, and further enhancing the strength and rigidity of the magnetic adjusting device. The magnetic adjusting column end cover 10 and the magnetic adjusting column pressing ring 4 are made of the same material as the magnetic adjusting column 6, which reduces the magnetic leakage and improves the stability of the magnetic adjusting column. The magnetic adjusting column base 6 is made of non-magnetic material such as stainless steel by casting and forming. The magnetic adjusting column base 6 is provided with a screw hole, which is convenient for fixing the magnetic adjusting device.

[0032] The outer rotor yoke 2 is hollowed inside and provided with a slot. Three permanent magnets are integrally attached inside the slot. The permanent magnets are magnetized in the manner as shown in Figure 2 The one-way magnetization manner can reduce the magnetic flux between the outer rotor permanent magnets. The embedded slot design effectively reduces the end magnetic leakage of the outer rotor permanent magnet 3 and improves the utilization rate of the permanent magnet.

Claims

1. A coaxial magnetic gear with a permanent magnet embedded magnetic focusing type magnetic adjustment device, comprising an outer rotor assembly, an inner rotor assembly, and a magnetic adjustment device; the outer rotor assembly includes a driven shaft, an outer rotor yoke, and an outer rotor permanent magnet, the outer rotor yoke and the driven shaft being connected by a key, and a shoulder is designed on the driven shaft for positioning; the inner rotor assembly includes a drive shaft, an inner rotor yoke, and an inner rotor permanent magnet, the inner rotor yoke and the drive shaft being connected by a key, the drive shaft also having a shoulder for positioning, and the inner rotor permanent magnets being closely arranged and surface-mounted on the surface of the inner rotor yoke; characterized in that... The outer rotor yoke has a hollowed-out structure with grooves on its inner wall. Permanent magnets are installed face-to-face within these grooves in a tightly arranged configuration, with three permanent magnets per groove and zero gap between them. Magnetization is unidirectional. The magnetizing assembly includes a magnetizing column pressure ring or end cap, a magnetizing column, and a magnetizing column base. This assembly is installed between the outer rotor assembly and the inner rotor assembly. The bottom of the magnetizing column is welded to the base, and the pressure ring or end cap is welded to the top of the magnetizing column, thus fixing the entire magnetizing device. The number of magnetizing columns is n. s The number of pole pairs of the inner rotor permanent magnet is P1, and the number of pole pairs of the outer rotor permanent magnet is P2. These three satisfy the following relationship: n s =P1+P2.

2. The coaxial magnetic gear of the permanent magnet embedded magnetic focusing type magnetic adjustment device as described in claim 1, characterized in that: The side of the adjusting column is a 1 / 2 period sine curve, which improves the magnetization effect. It is welded to the adjusting column base and adjusting column pressure ring to form the entire magnetization device, enhancing its reliability. The expression for the 1 / 2 period sine curve on the side of the adjusting column is: In the formula, A is the amplitude of the 1 / 2 period sine curve, and H... s To adjust the radial thickness of the magnetic pole piece, the side shape is changed by altering the value of A in the function during the fabrication of the magnetic adjustment column, thereby changing the magnetic focusing effect of the column.

3. The coaxial magnetic gear of the permanent magnet embedded magnetic focusing type magnetic adjustment device as described in claim 1, characterized in that: When the magnetic adjustment device is fixed in a non-enclosed manner, it consists of three parts: a magnetic adjustment column base, a magnetic adjustment column, and a magnetic adjustment column pressure ring. The magnetic adjustment column base and the magnetic adjustment column are installed together. The magnetic adjustment column pressure ring has a groove on one side that matches the shape of the magnetic adjustment column, and then it is installed together with the magnetic adjustment column. The magnetic adjustment column is made of DT4 industrial pure iron or No. 10 steel. The magnetic adjustment column base and the magnetic adjustment column pressure ring are made of high-strength non-magnetic materials, including stainless steel. The connection method is welding.

4. The coaxial magnetic gear of the permanent magnet embedded magnetic focusing type magnetic adjustment device as described in claim 1, characterized in that: When the magnetic adjustment device is fixed in a closed manner, it consists of three parts: magnetic adjustment column base, magnetic adjustment column, and magnetic adjustment column end cap. The installation method is the same as that of the non-closed type. The magnetic adjustment column end cap used in the closed installation can reduce the leakage magnetic field at the end of the inner rotor permanent magnet and achieve the axial magnetic focusing effect. The magnetic adjustment column end cap and magnetic adjustment column are made of DT4 industrial pure iron or No. 10 steel and are manufactured using 3D printing technology or casting method.

5. The coaxial magnetic gear of the permanent magnet embedded magnetic focusing type magnetic adjustment device as described in claim 1, characterized in that: The edges of the magnetic column side, the magnetic column pressure ring, and the two end faces of the magnetic column end cover are all rounded to reduce the magnetic saturation phenomenon at the sharp corners when the magnetic gear is working.

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