阅读说明：本技术 永磁装置 (Permanent magnet device ) 是由 何叶青 王进东 于 2019-09-03 设计创作，主要内容包括：本公开涉及一种永磁装置,包括磁发生部和分别设置在磁发生部的两极的第一磁轭和第二磁轭,第一磁轭的末端设置有第一极头,第二磁轭的末端设置有第二极头,第一极头和第二极头相对设置以形成气隙磁场,磁发生部包括：第一永磁体,产生第一磁场,第一永磁体固定在第一磁轭和第二磁轭之间；和第二永磁体,产生第二磁场,第二永磁体可转动地设置在第一磁轭和第二磁轭之间,以使第二永磁体作用在第一磁轭和第二磁轭中的磁通随第二永磁体的转动而变化。设置可转动地第二永磁体,实现气隙磁场的磁场强度在一定范围内的持续可调,满足不同能量的粒子束对撞时对气隙磁场的磁感应强度的不同需求。相较于电磁式的调节方式,降低了使用及维护成本。(The utility model relates to a permanent magnet device, including magnetism generation portion and first yoke and the second yoke of setting respectively at the two poles of the earth of magnetism generation portion, the end of first yoke is provided with first polar head, and the end of second yoke is provided with the second polar head, and first polar head and second polar head set up relatively in order to form air gap magnetic field, and magnetism generation portion includes: the first permanent magnet generates a first magnetic field, and is fixed between the first magnetic yoke and the second magnetic yoke; and a second permanent magnet generating a second magnetic field, the second permanent magnet being rotatably disposed between the first yoke and the second yoke such that magnetic flux of the second permanent magnet acting in the first yoke and the second yoke varies with rotation of the second permanent magnet. The second permanent magnet is arranged in a rotatable mode, so that the magnetic field intensity of the air-gap magnetic field can be continuously adjusted within a certain range, and different requirements of particle beams with different energies on the magnetic induction intensity of the air-gap magnetic field during colliding are met. Compared with an electromagnetic adjusting mode, the use and maintenance cost is reduced.)

1. A permanent magnet device comprises a magnetic generating part, and a first magnetic yoke (11) and a second magnetic yoke (12) which are respectively arranged at two poles of the magnetic generating part, wherein a first pole head (13) is arranged at the tail end of the first magnetic yoke (11), a second pole head (14) is arranged at the tail end of the second magnetic yoke (12), the first pole head (13) and the second pole head (14) are relatively arranged to form an air gap magnetic field (100), and the magnetic generating part comprises:

a first permanent magnet (10) generating a first magnetic field, the first permanent magnet (10) being fixed between the first yoke (11) and the second yoke (12); and

and a second permanent magnet (20) generating a second magnetic field, the second permanent magnet (20) being rotatably disposed between the first yoke (11) and the second yoke (12) such that a magnetic flux of the second magnetic field acting in the first yoke (11) and the second yoke (12) varies with the rotation of the second permanent magnet (20).

2. A permanent magnet device according to claim 1, characterized in that the first yoke (11) and the second yoke (12) enclose a C-shaped structure, the second permanent magnet (20) is arranged at a side wall of the C-shaped structure, the first pole head (13) and the second pole head (14) are arranged at an open end of the C-shaped structure, the first permanent magnet (10) is arranged between the open end and the side wall, and the first permanent magnet (10) is arranged at a distance from the second permanent magnet (20).

3. The permanent magnet device according to claim 2, further comprising a third yoke (21) and a fourth yoke (22) respectively clamped at two poles of the second permanent magnet (20), and a driving mechanism for driving the third yoke (21) and the fourth yoke (22) to rotate.

4. A permanent magnet device according to claim 3, characterized in that the third yoke (21) and the fourth yoke (22) are formed on the sides facing away from the second permanent magnet (20) as circular cylindrical surfaces with the axis of rotation of the second permanent magnet (20) as the axis, and the first yoke (11) and the second yoke (12) are formed with circular concave surfaces matching the shape of the circular cylindrical surfaces, respectively.

5. A permanent magnet device according to claim 3, characterized in that the drive mechanism comprises a motor (30), a first gear (31) connected to the output shaft of the motor (30), a second gear (32) meshing with the first gear (31), and a mounting shaft (33) coaxially mounted on the second gear (32), the third yoke (21) and the fourth yoke (22) being fixed to the mounting shaft (33), respectively.

6. A permanent magnet arrangement according to claim 2, characterized in that one pole of the first permanent magnet (10) is connected to the first yoke (11) by a fifth yoke (15) and the other pole is connected to the second yoke (12) by a sixth yoke (16).

7. A permanent magnet arrangement according to claim 2, characterized in that a lead plate (42) capable of separating the air-gap field (100) from the first permanent magnet (10) is mounted between the first yoke (11) and the second yoke (12).

8. A permanent magnet arrangement according to claim 7, characterized in that a non-magnetically conductive support beam (41) is mounted between the first yoke (11) and the second yoke (12), and that the lead plate (42) is fixed to the support beam (41).

9. A permanent-magnet device according to claim 8, characterised in that said plates (42) are in a plurality of pieces, arranged on either side of said supporting beam (41).

10. A permanent magnet device according to any of claims 2-9, characterized in that the permanent magnet device is constructed as a symmetrical structure with the centre line of the C-shaped structure as the symmetry axis.

Technical Field

The present disclosure relates to the field of permanent magnet technology, and in particular, to a permanent magnet device.

Background

At present, the application field of the permanent magnet device is increasingly wide, and the permanent magnet device mainly comprises two magnets, wherein the two magnets can provide a uniform and unidirectional air gap magnetic field. When the permanent magnet device is applied to a positive and negative particle collider, the Lorentz force generated by the air gap magnetic field on the charged particles forces the moving charged particles to deflect, so that the aim of controlling the running track of a particle beam is fulfilled, and two beams of positive and negative particles are accurately collided. Because the length of the track of the colliders reaches dozens of kilometers or even hundreds of kilometers, each collider needs thousands of dipolar magnets to regulate and control the running track of particle beams, and the final accurate collision of particles is realized, so that the collision efficiency reaches the highest.

In order to achieve precise collision of particles, it is necessary to make the field strength of the air-gap magnetic field of thousands of dipolar magnets uniform in uniformity and stability. However, due to the difference in material, dimensional tolerance and connection tolerance between the parts, the performance of thousands of dipolar magnets cannot be completely the same, and these factors are enough to cause the difference in air gap magnetic field strength between different dipolar magnets to exceed the unevenness required for controlling the particle track, which makes the particles unable to achieve precise collision and the collision efficiency unable to reach the best. Furthermore, the required strength of the airgap field is different for different energy beams, which requires a permanent magnet arrangement for accommodating multiple energy beams.

Currently, there is an electromagnetic type diode magnet that adjusts the field intensity of each diode magnet by controlling the magnitude of current so that the field intensities of thousands of diode magnets are uniform. However, the power consumption of each dipole magnet is as high as tens of kilowatts or even hundreds of kilowatts, and the energy consumption of thousands of dipole magnets is enormous, and also requires a large and complex cooling system, and the cost of these energy consumptions and the maintenance and repair costs of the system make the apparatus expensive.

Disclosure of Invention

It is an object of the present disclosure to provide a permanent magnet arrangement to enable adjustment of the field strength of an air-gap magnetic field.

In order to achieve the above object, the present disclosure provides a permanent magnet device including a magnetic generating portion, and a first yoke and a second yoke respectively disposed at two poles of the magnetic generating portion, wherein a first pole head is disposed at an end of the first yoke, a second pole head is disposed at an end of the second yoke, the first pole head and the second pole head are disposed opposite to each other to form an air gap magnetic field, and the magnetic generating portion includes: a first permanent magnet generating a first magnetic field, the first permanent magnet being fixed between the first yoke and the second yoke; and a second permanent magnet generating a second magnetic field, the second permanent magnet being rotatably disposed between the first yoke and the second yoke such that a magnetic flux of the second magnetic field acting in the first yoke and the second yoke varies with rotation of the second permanent magnet.

Optionally, the first magnetic yoke and the second magnetic yoke enclose a C-shaped structure, the first pole head and the second pole head are disposed at an open end of the C-shaped structure, the second permanent magnet is disposed on a side wall of the C-shaped structure, the first permanent magnet is disposed between the open end and the side wall, and the first permanent magnet and the second permanent magnet are disposed at an interval.

Optionally, the permanent magnet device further comprises a third magnetic yoke and a fourth magnetic yoke respectively clamped at two poles of the second permanent magnet, and a driving mechanism for driving the third magnetic yoke and the fourth magnetic yoke to rotate.

Optionally, the third magnetic yoke and the fourth magnetic yoke are respectively formed into arc cylindrical surfaces with the rotating shaft of the second permanent magnet as an axis, and the first magnetic yoke and the second magnetic yoke are respectively formed with arc concave surfaces matched with the arc cylindrical surfaces in shape.

Optionally, the driving mechanism includes a motor, a first gear connected to the output shaft of the motor, a second gear engaged with the first gear, and an installation shaft coaxially installed on the second gear, and the third yoke and the fourth yoke are fixed on the installation shaft respectively.

Optionally, one magnetic pole of the first permanent magnet is connected with the first magnetic yoke through a fifth magnetic yoke, and the other magnetic pole of the first permanent magnet is connected with the second magnetic yoke through a sixth magnetic yoke.

Optionally, a lead plate capable of separating the air gap magnetic field from the first permanent magnet is installed between the first yoke and the second yoke.

Optionally, a non-magnetic-conductive support beam is installed between the first magnetic yoke and the second magnetic yoke, and the lead plate is fixed on the support beam.

Optionally, the number of the lead plates is multiple, and the lead plates are respectively arranged on two sides of the supporting beam.

Optionally, the permanent magnet device is configured as a symmetrical structure with a center line of the C-shaped structure as a symmetry axis.

Optionally, the side edges of the first pole head and the second pole head are respectively provided with a field adjusting plate capable of approaching or departing from each other.

Optionally, a temperature compensation plate and/or a magnetic conduction plate are detachably mounted on the side surface of the first permanent magnet.

Optionally, a temperature compensation plate and/or a magnetic conduction plate are detachably mounted on the side surface of the second permanent magnet.

Through the technical scheme, the first permanent magnet and the second permanent magnet and the first magnetic yoke and the second magnetic yoke jointly generate an air gap magnetic field, and the magnetic induction intensity of the air gap magnetic field is jointly determined by magnetic fluxes of the first magnetic field and the second magnetic field acting in the first magnetic yoke and the second magnetic yoke. The magnetic flux of a first magnetic field generated by the first permanent magnet and acting in the first magnetic yoke and the second magnetic yoke is always kept unchanged, and the magnetic flux of a second magnetic field of the second permanent magnet and acting in the first magnetic yoke and the second magnetic yoke is changed by rotating the second permanent magnet, so that the magnetic induction intensity of the air-gap magnetic field is changed accordingly. Through setting up rotatable second permanent magnet to realize that the magnetic induction intensity of air gap magnetic field is continuously adjustable in certain extent, when this permanent magnet device is applied to during the positive negative particle collider, can be so that the magnetic induction intensity that is used for forming the air gap magnetic field of a plurality of permanent magnet devices of particle track is unified, and then guarantees the accurate nature of particle collided, and this permanent magnet device can satisfy different demands to the magnetic induction intensity of air gap magnetic field when the particle beam of different energies collided, and adaptability is strong. In addition, compared with an electromagnetic adjusting mode, the permanent magnet device disclosed by the invention greatly reduces the use and maintenance cost.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is a schematic structural diagram of one state of a permanent magnet apparatus provided in an exemplary embodiment of the present disclosure;

FIG. 2 is a schematic structural view of another state of a permanent magnet apparatus provided in an exemplary embodiment of the present disclosure;

FIG. 3 is a schematic structural view of another state of a permanent magnet apparatus provided in an exemplary embodiment of the present disclosure;

FIG. 4 is a structural schematic diagram of another state of a permanent magnet apparatus provided in an exemplary embodiment of the present disclosure;

FIG. 5 is a partial enlarged view of portion A of FIG. 1;

fig. 6 is a partial structural schematic diagram of a permanent magnet device according to an exemplary embodiment of the present disclosure.

Description of the reference numerals

100 air gap field 10 first permanent magnet 11 first yoke

12 second yoke 13 first pole head 14 second pole head

15 fifth yoke 16 sixth yoke 20 second permanent magnet

21 third yoke 22 fourth yoke 41 support beam

42 lead plate 43 field plate 51 temperature compensation sheet

52 magnetic conductive sheet 30 motor 31 first gear

32 second gear 33 mounting shaft

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, the terms of orientation such as "inside and outside" are used with respect to the self-outline of the component parts without being described to the contrary, and in addition, the terms "first", "second", and the like used in the embodiments of the present disclosure are used for distinguishing one element from another element without order and importance. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated.

As shown in fig. 1 to 4, the present disclosure provides a permanent magnet device including a magnetic generating part and first and second yokes 11 and 12 respectively disposed at two poles of the magnetic generating part, a first pole head 13 disposed at an end of the first yoke 11, a second pole head 14 disposed at an end of the second yoke 12, the first and second pole heads 13 and 14 being disposed opposite to each other to form an air-gap magnetic field 100. The magnetic generating part comprises a first permanent magnet 10 and a second permanent magnet 20, and because the equipment of the permanent magnets is large under some conditions and cannot be directly manufactured integrally, the first permanent magnet 10 and the second permanent magnet 20 can be respectively formed by a plurality of small magnets with the same size, magnetism and polarity in a bonding mode and the like, and the periphery of the bonded permanent magnets can be fixed by a fixing frame and other devices. In the present disclosure, the first permanent magnet 10 is fixed between the first magnetic yoke 11 and the second magnetic yoke 12, so that the direction of the first magnetic field of the first permanent magnet 10 is fixed and unchanged, and the magnetic flux of the first permanent magnet 10 acting in the first magnetic yoke 11 and the second magnetic yoke 12 is always kept unchanged; the second permanent magnet 20 is rotatably disposed between the first yoke 11 and the second yoke 12, so that a magnetic flux of a second magnetic field generated by the second permanent magnet 20 acting in the first yoke 11 and the second yoke 12 varies with the rotation of the second permanent magnet 20; and with the rotation of second permanent magnet 20, the polarity of the second magnetic field acting on first yoke 11 and second yoke 12 will also change, namely when second permanent magnet 20 rotates to a certain angle, its N-pole end face is closest to first yoke 11, when second permanent magnet 20 rotates to another angle, its N-pole end face is closest to second yoke 12. The first pole head 13 and the second pole head 14 are respectively disposed on opposite sides of the first yoke 11 and the second yoke 12, i.e., inside of a C-shaped structure described below, and the first pole head 13 and the second pole head 14 are identical in structure to make the magnetic induction intensity of the air-gap magnetic field 100 uniform. In order to make the magnetic permeability of the first and second yokes 11 and 12 higher, the first and second permanent magnets 10 and 20 are disposed close to or in contact with the first and second yokes 11 and 12 to reduce magnetic leakage as much as possible.

Through the technical scheme, the first permanent magnet 10 and the second permanent magnet 20 and the first magnetic yoke 11 and the second magnetic yoke 12 jointly generate the air gap magnetic field 100, and the magnetic induction intensity of the air gap magnetic field is jointly determined by the magnetic fluxes of the first magnetic field and the second magnetic field acting in the first magnetic yoke 11 and the second magnetic yoke 12. The magnetic flux of the first magnetic field generated by the first permanent magnet 10 acting on the first magnetic yoke 11 and the second magnetic yoke 12 is always kept unchanged, and the magnetic flux of the second magnetic field of the second permanent magnet 20 acting on the first magnetic yoke 11 and the second magnetic yoke 12 is changed by rotating the second permanent magnet 20, so that the magnetic induction intensity of the air-gap magnetic field 100 is changed accordingly. Through setting up rotatable second permanent magnet 20 to realize that the magnetic induction intensity of air gap magnetic field 100 lasts adjustable in certain extent, when this permanent magnet device is applied to during the positive negative particle collider, can be so that the magnetic induction intensity that is used for forming the air gap magnetic field 100 of a plurality of permanent magnet devices of particle track is unified, and then guarantee the accurate nature of particle collided, and this permanent magnet device can satisfy different demands to the magnetic induction intensity of air gap magnetic field 100 when the particle beam of different energies collided, and adaptability is strong. In addition, compared with an electromagnetic adjusting mode, the permanent magnet device disclosed by the invention greatly reduces the use and maintenance cost.

According to an embodiment of the present disclosure, as shown in fig. 1 to 4, the first and second yokes 11 and 12 may enclose a C-shaped structure, the first and second pole heads 13 and 14 are disposed at an open end of the C-shaped structure, the second permanent magnet 20 is disposed at a side wall of the C-shaped structure, the first permanent magnet 10 is disposed between the open end and the side wall, and the first and second permanent magnets 10 and 20 are disposed at a distance. It should be noted that the C-shaped structure herein refers to a general shape enclosed by the first and second yokes 11 and 12, that is, refers to a shape of a device having an opening for forming the air-gap magnetic field 100, not the whole device, and does not limit the specific structure of the first and second yokes 11 and 12. The C-shaped structure of the permanent magnet device can be changed into a U-shaped similar shape with an opening at one end. The first yoke 11 and the second yoke 12 do not directly contact with each other, so that magnetic lines of force of the first magnetic field of the first permanent magnet 10 and the second magnetic field of the second permanent magnet 20 pass through the first yoke 11 or the second yoke 12 and are conducted to the first pole head 13 and the second pole head 14 to form the air gap magnetic field 100. The second permanent magnet 20 is arranged on the side wall of the C-shaped structure, i.e. at a position close to the outer edge of the permanent magnet arrangement, where it provides a larger operating space for the second permanent magnet 20, which facilitates the adjustment of the permanent magnet arrangement when mounted. The first permanent magnet 10 is arranged between the open end and the side wall, i.e. in the middle area of the C-shaped structure, which also effectively improves the space utilization of the permanent magnet arrangement.

Referring to fig. 1 to 4, one magnetic pole of the first permanent magnet 10 may be connected to the first yoke 11 through the fifth yoke 15, and the other magnetic pole may be connected to the second yoke 12 through the sixth yoke 16. Since the manufacturing process of integrally molding the first and second yokes 11 and 12 and the fifth and sixth yokes 15 and 16 is complicated and costly, the first permanent magnet 10 is connected to the first and second yokes 11 and 12 by the two other yokes in the embodiment of the present disclosure, which is convenient to manufacture and economical. Here, the fifth yoke 15 and the sixth yoke 16 may be respectively coupled to side walls (i.e., both walls on both upper and lower sides in the drawing direction in fig. 1 to 4) of the C-shaped structure.

In the embodiment of the present disclosure, as shown in fig. 1 to 4 and 6, in consideration of the material properties of the second permanent magnet 20 and the volume size thereof, in order to facilitate structural installation of the second permanent magnet 20, the permanent magnet device may further include a third yoke 21 and a fourth yoke 22 respectively clamped at two poles of the second permanent magnet 20, and a driving mechanism for driving the third yoke 21 and the fourth yoke 22 to rotate. Meanwhile, the third and fourth yokes 21 and 22 may also protect the second permanent magnet 20 from damage during rotation. The third yoke 21 and the fourth yoke 22 may have the same structure.

According to an embodiment of the present disclosure, as shown in fig. 1 to 4, the sides of the third and fourth yokes 21 and 22 away from the second permanent magnet 20 are respectively formed as circular arc cylindrical surfaces with the rotation axis of the second permanent magnet 20 as an axis, and the first and second yokes 11 and 12 are respectively formed with circular arc concave surfaces matched with the circular arc cylindrical surfaces, that is, the circular arc concave surfaces and the circular arc cylindrical surfaces are both axial lines with the rotation axis of the second permanent magnet 20, so that the third and fourth yokes 21 and 22 can be well matched or attached to the first and second yokes 11 and 12, and the second permanent magnet 20 is always rotated along the contour of the circular arc concave surfaces. Wherein, referring to fig. 6, the sides of the third and fourth yokes 21 and 22 facing away from the second permanent magnet 20 refer to the opposite sides to the sides contacting the second permanent magnet 20. The shape of one side of the third and fourth yokes 21 and 22 for holding the second permanent magnet 20 matches the outer contour of the second permanent magnet 20 to enhance the magnetic conductive effect on the second permanent magnet 20.

According to an embodiment of the present disclosure, referring to fig. 1 to 4, the arc of the arc concave surface may be equal to the arc of the arc cylindrical surface. Therefore, on the one hand, the magnetic flux of the second magnetic field acting on the first magnetic yoke 11 and the second magnetic yoke 12 can be changed when the second permanent magnet 20 rotates by an angle, so that the magnetic induction intensity of the air-gap magnetic field 100 can be adjusted, and the influence on the control accuracy of the permanent magnet device caused by the unchanged magnetic induction intensity of the air-gap magnetic field 100 after the second permanent magnet 20 rotates is avoided. On the other hand, this design also facilitates the manufacture of the first yoke 11, the second yoke 12, the third yoke 21, and the fourth yoke 22.

Specifically, the adjustment of the permanent magnet device in one embodiment of the present disclosure is briefly described below with reference to the accompanying drawings. In fig. 1, the direction of magnetic lines of force generated by the first magnetic field of the permanent magnetic device passing through the first magnetic yoke 11 and the second magnetic yoke 12 is the same as the direction of magnetic lines of force generated by the second magnetic field passing through the first magnetic yoke 11 and the second magnetic yoke 12, and the magnetic induction intensity of the whole air-gap magnetic field 100 is the superposition of magnetic fluxes of the first magnetic field and the second magnetic field acting in the first magnetic yoke 11 and the second magnetic yoke 12, in which case, the magnetic induction intensity of the air-gap magnetic field 100 is the maximum; the second permanent magnet 20 in fig. 2 is rotated clockwise by a certain angle, and at this time, the magnetic resistance of the second magnetic field in the first and second yokes 11 and 12 increases due to the deflection of the third and fourth yokes 21 and 22 in comparison with the first and second yokes 11 and 12, and the magnetic flux of the second magnetic field acting in the first and second yokes 11 and 12 decreases. In this case, the magnetic induction of the air-gap magnetic field 100 is reduced; in fig. 3, the second permanent magnet 20 further rotates clockwise, and at this time, the magnetic flux of the second magnetic field of the second permanent magnet 20 acting on the first and second yokes 11 and 12 is reduced, the direction of the magnetic force lines generated by the second magnetic field passing through the first and second yokes 11 and 12 is changed, and the direction of the magnetic force lines generated by the second magnetic field is opposite to the direction of the magnetic force lines generated by the first magnetic field passing through the first and second yokes 11 and 12, in this case, the magnetic flux of the second magnetic field acting on the first and second yokes 11 and 12 has the effect of canceling part of the magnetic flux of the first magnetic field acting on the first and second yokes 11 and 12, so that the magnetic induction intensity of the air-gap magnetic field 100 is further reduced than that in the previous process; in fig. 4, the second permanent magnet 20 continues to rotate clockwise to a position where the second magnetic field is opposite to the first magnetic field, and the magnetic induction intensity of the air-gap magnetic field 100 is the difference between the magnetic flux of the first magnetic field acting on the first magnetic yoke 11 and the second magnetic yoke 12 and the magnetic flux of the second magnetic field acting on the first magnetic yoke 11 and the second magnetic yoke 12, in this case, the magnetic induction intensity of the air-gap magnetic field 100 reaches the minimum; then, the second permanent magnet 20 is rotated clockwise, the magnetic induction of the air-gap magnetic field 100 will gradually increase and return to the original state, the specific principle is the same as the above process, and the process is not repeated here. In summary, the magnetic flux adjustable range in the magnetic circuit of the permanent magnet device is between the difference between the first magnetic field and the second magnetic field and the range of the sum of the first magnetic field and the second magnetic field, the magnetic induction intensity range of the air-gap magnetic field 100 is provided by the adjustable magnetic flux range, and when the magnetic flux of the first magnetic field acting on the first magnetic yoke 11 and the second magnetic yoke 12 and the magnetic flux of the second magnetic field acting on the first magnetic yoke 11 and the second magnetic yoke 12 are equal, the minimum value of the magnetic induction intensity of the air-gap magnetic field 100 is 0.

Referring to fig. 6, the driving mechanism for driving the second permanent magnet 20 to rotate may include a motor 30, a first gear 31 connected to an output shaft of the motor 30, a second gear 32 engaged with the first gear 31, and a mounting shaft 33 coaxially mounted on the second gear 32, and the third and fourth yokes 21 and 22 are fixed to the mounting shaft 33, respectively. The gear is used, so that the rotation stability is higher, and the rotation accuracy of the second permanent magnet 20 is good. The diameter of the first gear 31 may be smaller than that of the second gear 32, so that the reduction transmission may be implemented, such that the second permanent magnet 20 can rotate at a small angle to fine-tune the magnetic induction of the air-gap magnetic field 100. The opening and the rotation speed of the motor 30 can be precisely controlled remotely by the control terminal, so as to adjust the rotation angle of the second permanent magnet 20, for example, a sensor for detecting a magnetic induction signal of the air-gap magnetic field 100 can be disposed near the air-gap magnetic field 100, and then the signal is fed back to the control terminal, and the control terminal sends a corresponding command to control the motor 30. In other embodiments, the driving method of the driving mechanism may be a belt drive, a worm gear, or the like, and the present disclosure is not limited thereto.

Referring to fig. 1 to 4, a lead plate 42 capable of separating an air-gap magnetic field 100 from a first permanent magnet 10 is installed between a first yoke 11 and a second yoke 12. When high-energy particles move in a circular orbit formed by a plurality of air gap magnetic fields 100, centripetal acceleration causes the particles to generate high-energy electromagnetic radiation, so that the high-energy particles can release radiation to the periphery at any time in the operation process, the high-dose strong radiation can cause the distortion of the crystal structure of the permanent magnet material, the residual magnetism of the permanent magnet is reduced, even the permanent magnet is damaged, the radiation protection effect of lead is good, therefore, by arranging the lead plate 42 to separate the air-gap magnetic field 100 from the first permanent magnet 10, the first permanent magnet 10 can be effectively prevented from being damaged by electromagnetic radiation, since the second permanent magnet 20 is located on the side of the first permanent magnet 10 remote from the air-gap field 100, the arrangement of the lead plate 42 between the first permanent magnet 10 and the air gap field 100 also protects the second permanent magnet 20 from radiation, when the second permanent magnet 20 is located at another position, a lead plate may be additionally disposed between the second permanent magnet 20 and the air gap magnetic field 100. The lead is soft, and both ends of the lead plate 42 may be respectively bonded to the first and second yokes 11 and 12 to be fixed. According to another embodiment of the present disclosure, a supporting beam 41 without magnetic conductivity may be installed between the first magnetic yoke 11 and the second magnetic yoke 12, and the lead plate 42 may also be fixed on the supporting beam 41, for example, the lead plate 42 may be installed by bolting or riveting. The non-magnetic support beam 41 is supported between the first yoke 11 and the second yoke 12 formed in the C-shaped structure as described above, and supports the first yoke 11 and the second yoke 12, thereby ensuring structural stability of the permanent magnet device. The material of the support beam 41 may be non-magnetic or weakly magnetic stainless steel, copper alloy or ceramic, etc. to avoid affecting the magnetic circuit of the permanent magnet device.

In addition, the number of the lead plates 42 may be multiple, and referring to fig. 1 to 4, for example, two lead plates 42 may be provided on both sides of the support beam 41. The radiation protection function of the permanent magnet can be enhanced by arranging the lead plates 42, and the service life of the permanent magnet is prolonged.

Referring to fig. 1, in the disclosed embodiment, the permanent magnet device is configured as a symmetrical structure having a center line of the C-shaped structure as a symmetry axis. In the art, a symmetry plane between the N pole and the S pole of the magnet is referred to as a neutral plane, in other words, the permanent magnet device is configured as a symmetrical structure with the neutral plane as a symmetry plane, and the rotation axis of the second permanent magnet 20 passes through the symmetry plane, thereby making the path lengths of the magnetic lines of force generated by the permanent magnets to the air-gap magnetic field 100 via the first yoke 11 and via the second yoke 12 equal, that is, the magnetic resistances of both poles of the permanent magnet are equal, and thus making the uniformity of the magnetic induction intensity of the air-gap magnetic field 100 optimal.

As shown in fig. 1 to 4, the side edges of the first and second heads 13 and 14 are respectively provided with a field adjusting plate 43 capable of approaching or separating from each other. The magnetic lines of force at the air-gap magnetic field 100 repel each other, so the magnetic lines of force will bend towards the outside of the pole head at the edge of the air-gap magnetic field 100, and the expansion of the magnetic lines of force can be reduced by adjusting the opposite movement of the field-adjusting plates 43, thereby ensuring the uniformity of the air-gap magnetic field 100 and better controlling the movement track of the particles. The uniformity of the air-gap magnetic field 100 can be improved by adjusting the thickness of the field adjusting plate 43, and the thicker the field adjusting plate 43 is, the more magnetic lines are derived, and the more obvious the effect of adjusting the uniformity of the air-gap magnetic field 100 is.

According to one embodiment of the present disclosure, as shown in fig. 5, a temperature compensation plate 51 and/or a magnetic conductive plate 52 are detachably mounted on a side surface of the first permanent magnet 10. The temperature compensation sheet 51 is a weak magnetic Ni-Fe alloy with Curie temperature close to room temperature, and can play a role in offsetting the change of the magnetism of the first permanent magnet 10 along with the temperature, so that the amplitude of the field intensity of the air-gap magnetic field 100 along with the temperature change is kept in a stable range, and the normal work of the permanent magnet device is prevented from being influenced by the temperature; the magnetic conductive sheet 52 is a ferromagnetic sheet including an iron sheet, a steel sheet, and the like, and because of its high magnetic permeability, part of the magnetic lines of force can be directly conducted from the N pole of the first permanent magnet 10 to the S pole, thereby reducing the magnetic flux acting on the magnetic yoke by the first permanent magnet 10, the more the magnetic conductive sheets 52 are, the less the total magnetic flux of the air-gap magnetic field 100 is, and the magnetic conductive sheets 52 with different numbers can be set, thereby further playing a role in adjusting the upper and lower limits of the magnetic induction intensity of the air-gap magnetic field 100, and thus ensuring the consistency of multiple devices. The temperature compensation plate 51 and the magnetic conductive plate 52 can act on the first permanent magnet 10 individually, and also can act on the first permanent magnet 10 together, wherein the temperature compensation plate 51 is attached to the first permanent magnet 10 to sense the temperature of the first permanent magnet 10 quickly and accurately, and the magnetic conductive plate 52 can be mounted on the temperature compensation plate 51 through a fastener. The temperature compensation plate 51 and the magnetic conductive plate 52 may be provided on all the side of the first permanent magnet 10 to which no yoke is attached. Without the temperature-compensating plates 51, it is also possible to balance the change in the air-gap magnetic field 100 due to temperature changes by rotating the second permanent magnet 20.

Similarly, the side surface of the second permanent magnet 20 may also be detachably mounted with a temperature compensation plate 51 and/or a magnetic conductive plate 52, and the mounting manner and principle function thereof are the same as those described above, and are not described herein again.

In the embodiment of the present disclosure, the material of the first permanent magnet 10 and the second permanent magnet 20 may be a rare earth permanent magnet material, such as Nd — Fe — B material or Sm — Co material, or may also be ferrite, alnico, or other permanent magnet material, or may also be a combination of different permanent magnet materials. The pole head, the yoke, the field plate 43 and the magnetic conductive plate 52 can be made of high magnetic conductivity materials, such as pure iron, iron-cobalt alloy or carbon steel.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.