Magnetic field array polishing device

Abstract

The invention relates to the technical field of polishing equipment, and discloses a magnetic field array polishing device which comprises an array carrier, a rotating shaft and an outer sleeve. Two rows of edge magnet sets and a row of middle magnet sets are arranged on the side face of the array carrier, one end of the rotating shaft is inserted into the bottom of the array carrier, the other end of the rotating shaft extends out of the array carrier, the rotating shaft is externally connected with an output source to drive the array carrier to rotate, and the outer sleeve is arranged on the outer side of the array carrier in a sleeving mode. According to the polishing device, each N-pole outward magnetic field is in an obvious brush shape, the N-pole brush-shaped magnetic fields are distributed in a continuous S-like shape from the side face of an array carrier, and when an array rotates by a circle, the number of times and the strength that all positions of any 30 mm long line segment outside the carrier parallel to the axial direction of the array carrier are scratched by a magnet are consistent; and therefore, magnetorheological polishing is more uniform and sufficient, and the efficiency and capacity of magnetorheological polishing are improved.

Description

Technical Field

[0001] The invention relates to the technical field of polishing equipment, and in particular to a magnetic field array polishing device. Background Art

[0002] Magnetorheological fluid is composed of magnetizable micron-sized iron particles and a non-magnetizable matrix or carrier fluid and additives to combat sedimentation and agglomeration. The rheological properties of magnetorheological fluid change with the magnetic field. When there is no magnetic field, it can flow freely. When a magnetic field is applied, it can quickly transform into a solid-like structure within milliseconds. Magnetorheological polishing fluid is obtained by adding abrasives to magnetorheological fluid and stirring it thoroughly.

[0003] Magnetorheological polishing technology is the technology of polishing objects with magnetorheological polishing fluid. It has the characteristics of high machining surface accuracy, small surface roughness, controllable machining process, small sub-surface damage depth, and no new damage during the machining process. It is mostly used in ultra-precision machining fields with very high machining accuracy requirements, the most common of which is the surface machining of optical parts.

[0004] Figure 1 The figure shows the changes of carbonyl iron powder particles (CIPs) and abrasive particles in the magnetorheological polishing fluid with and without a magnetic field. It can be seen from the figure that when there is no magnetic field, the carbonyl iron powder particles and the abrasive particles are randomly mixed in the base liquid, and the liquid can flow freely; when the magnetic field is applied, the carbonyl iron powder particles will form a chain arrangement along the direction of the magnetic field and randomly sandwich the abrasive particles between them, thus the carbonyl iron powder particles and the abrasive particles form a chain. Figure 1 (b) The linear sandwich chain structure; when the magnetic field and shear strain are applied at the same time, the shear strain will force the linear sandwich chain structure to deviate to the direction of the shear strain, and the gap between the particles inside the structure will increase but still remain in a linear chain shape, causing some abrasive particles to break away from the linear sandwich chain structure in the direction of the shear strain. A large number of free abrasive particles come into contact with the surface of the polishing object and shear the surface of the object under the combined action of the shear strain applied to the linear sandwich chain structure by the outside world and the magnetic tendency of the chain structure to return to its original direction, thereby achieving flexible polishing. This is the microscopic mechanism of magnetorheological polishing. As can be seen from the above, the magnetorheological polishing process is highly dependent on the external magnetic field. In theory, the stronger the external magnetic field, the higher the polishing efficiency and the stronger the polishing ability in the magnetorheological polishing process.

[0005] like Figure 2As shown in, Zhang Xianglei, Chen Zhuojie, etc., Study on Chemical Magnetorheological Polishing of Medical Titanium Alloy Halbach Magnetic Field Array [J]. Journal of Hunan University (Natural Science Edition), discloses a polishing device including an array carrier, a shaft, a magnet, and a copper sleeve. The manufacturing method is as follows: hollow out part of the array carrier, embed the magnet in the designated position according to the arrangement order of the Halbach array (a magnet array that can concentrate most of the magnet energy on one side to form a high-energy magnetic field, often used in industries such as CT machines and magnetic levitation that require high-energy magnetic fields), then insert the copper sleeve into the surface of the array carrier, and finally install the shaft. The high-energy magnetic field generated by the Halbach array makes the magnetic chain structure in the magnetorheological polishing liquid more stable, and the abrasive particles on its surface can generate greater pressure and shear force on the surface of the polished object, thereby improving the polishing efficiency and polishing ability.

[0006] However, the square magnets used in the above design make it difficult to process the magnet array. The magnetic induction intensity on the magnet surface is only less than 400mT at 2mm from the magnet surface, and the polishing distance is very limited. Summary of the invention

[0007] The purpose of the present invention is to provide a magnetic field array polishing device, which is easy to process and has a magnetic induction intensity of 610mT at 6mm from the N-pole surface of the magnet. The magnetic performance is much stronger than the existing technology and the polishing distance is also 3 times that of the existing technology.

[0008] In order to achieve the above object, the present invention provides a magnetic field array polishing device, comprising:

[0009] An array carrier, wherein two rows of edge magnet groups and one row of middle magnet groups are arranged on the side of the array carrier, the two rows of edge magnet groups are respectively arranged at the two ends of the side of the array carrier, the middle magnet group is arranged in the middle of the side of the array carrier, the first magnets on the two rows of edge magnet groups and the second magnets on the one row of middle magnet group are cylindrical magnets of the same size, the outward magnetic poles of adjacent first magnets in the same row are opposite, the outward magnetic poles of two first magnets in the same axial direction are opposite, the outward magnetic poles of the second magnets are both N poles, and the second magnets on the middle magnet group and the first magnets on the edge magnet group are arranged alternately;

[0010] A rotating shaft, one end of which is inserted into the bottom of the array carrier, and the other end of which extends out of the array carrier, and the rotating shaft is connected to an external output source to drive the array carrier to rotate;

[0011] A jacket is provided on the outer side of the array carrier.

[0012] Preferably, mounting holes corresponding to the first magnet and the second magnet are provided on the side surface of the array carrier.

[0013] Preferably, the angles between adjacent first magnets and adjacent second magnets are both 60°, and the angle between the first magnet and adjacent second magnet is 30°.

[0014] Preferably, the distance from the center of the first magnet to the nearest end of the array carrier is greater than the radius of the first magnet.

[0015] Preferably, the radius of the first magnet is 4 mm, and the distance from the center of the first magnet to the nearest end of the array carrier is 5.5 mm.

[0016] Preferably, the array carrier is an aluminum alloy cylinder with a diameter of 30 mm and a height of 30 mm.

[0017] Preferably, the rotating shaft is fixed in the array carrier via a pin.

[0018] Preferably, two first through holes and one second through hole are provided on the side of the array carrier, the axes of the first through hole and the second through hole are perpendicular to each other, and the rotating shaft is provided with insertion holes corresponding to the first through hole and the second through hole, and the rotating shaft is fixed to the array carrier by three pins passing through the corresponding first through hole and second through hole.

[0019] Preferably, the centers of the two first through holes are respectively collinear with the center lines of the two rows of edge magnet groups.

[0020] Preferably, the second through hole is arranged at the center of the side surface of the array carrier, and the center of the second through hole is colinear with the center line of the middle magnet group.

[0021] The beneficial effects of the present invention are as follows: the excellent magnetic properties of NdFeB are fully utilized, so that the effective polishing distance of the magnetic field array reaches 6mm, and the magnetic induction intensity at this location is above 0.61T, which is much higher than the magnetic field magnetic induction intensity generated by the Halbach array, and the magnetic field of each N pole facing outward is obviously brush-shaped, and the brush-shaped magnetic fields of multiple N poles are continuously distributed in an "S" shape when viewed from the side of the array carrier. When the array rotates one circle, the number of times and intensity of each location on any 30mm long line segment outside the carrier parallel to the axial direction of the array carrier being scratched by the magnet are consistent, making the magnetorheological polishing more uniform and sufficient, and improving the efficiency and capacity of the magnetorheological polishing.

[0022] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but do not constitute a limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 The changes of abrasive grains and iron powder particles in the presence and absence of magnetic field and external shear strain are shown;

[0025] Figure 2 A schematic diagram of a polishing array of the prior art is shown;

[0026] Figure 3 A schematic structural diagram of a magnetic field array polishing device according to an embodiment of the present invention is shown;

[0027] Figure 4 A schematic diagram of the structure of an array carrier according to an embodiment of the present invention is shown;

[0028] Figure 5 A schematic structural diagram of a magnetic field array polishing device according to an embodiment of the present invention is shown (excluding the outer jacket);

[0029] Figure 6 A schematic diagram of the rotating shaft structure of an embodiment of the present invention is shown;

[0030] Figure 7 A magnetic field simulation result diagram of an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0031] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0032] Please refer to Figure 2-Figure 7 The present embodiment discloses a magnetic field array polishing device, comprising an array carrier 1, a rotating shaft 2 and a jacket 3. Among them, two rows of edge magnet groups 11 and a row of middle magnet groups 12 are arranged on the side of the array carrier 1, the two rows of edge magnet groups 11 are respectively arranged at the two ends of the side of the array carrier 1, and the middle magnet group 12 is arranged in the middle of the side of the array carrier 1. The first magnets 111 on the two rows of edge magnet groups 11 and the second magnets 121 on the one row of middle magnet groups 12 are cylindrical magnets of the same size. The outward magnetic poles of the adjacent first magnets 111 in the same row are opposite, the outward magnetic poles of the two first magnets 111 in the same axial direction are opposite, and the outward magnetic poles of the second magnets 121 are both N poles. The second magnets 121 on the middle magnet group 12 and the first magnets 111 on the edge magnet group 11 are arranged alternately, one end of the rotating shaft 2 is inserted into the bottom of the array carrier 1, and the other end extends out of the array carrier 1. The rotating shaft 2 is connected to an external output source to drive the array carrier 1 to rotate, and the jacket 3 is sleeved on the outside of the array carrier 1. The side surface of the array carrier 1 is provided with mounting holes 101 corresponding to the first magnet 111 and the second magnet 121 .

[0033] In this embodiment, the array carrier 1 is a 6061 aluminum alloy cylinder with a diameter of 30 mm and a height of 30 mm. The first magnet 111 and the second magnet 121 are both N52 permanent magnets with a diameter of 8 mm and a thickness of 5 mm. The shaft 2 is a 304 stainless steel cylindrical shaft with a diameter of 7 mm and a thickness of 90 mm. The outer sleeve 3 is a uniform copper sleeve with an inner diameter of 30 mm, an outer diameter of 34 mm and a height of 30 mm.

[0034] The magnets in the prior art are rectangular parallelepipeds, which means that the magnetic field carrier needs to be processed into square holes and chamfered at the hole corners, which is very troublesome to process. However, the present embodiment only needs to drill round holes and through holes at the corresponding positions, which is relatively simple to process and has high production efficiency.

[0035] Please refer to Figure 2-Figure 5 During the specific processing, the CNC machine tool is used to drill the array carrier 1 blank to drill the mounting holes 101. Assume that from top to bottom, there are the first row, the second row, and the third row, the first row corresponds to the first end of the array carrier 1, and the third row corresponds to the second end of the array carrier 1. The first row and the third row correspond to two rows of edge magnet groups 11, and the second row corresponds to the middle magnet group 12. Each row is provided with 6 mounting holes 101, the interval angle between adjacent mounting holes 101 is 60°, the diameter of the drilled hole is 8mm, and the depth is 5mm. The mounting holes 101 in the first row are numbered 11, 12, 13, 14, 15, and 16, the mounting holes 101 in the second row are numbered 21, 22, 23, 24, 25, and 26, and the mounting holes 101 in the third row are numbered 31, 32, 33, 34, 35, and 36. The mounting holes 101 in the first row correspond to the mounting holes 101 in the third row. The spacing angle between the second row of mounting holes 101 and the adjacent third row of mounting holes 101 is 30°, that is, the spacing angle between hole 11 and hole 21 is 30°. The distance from the first row of mounting holes 101 to the first end of the array carrier 1 is the same as the distance from the third row of mounting holes 101 to the second end of the array carrier 1, both of which are 5.5 mm. The distance from the second row of mounting holes 101 to both ends of the array carrier 1 is the same, both of which are 15 mm. After the mounting holes 101 are drilled, the first magnet 111 and the second magnet 121 are installed in the corresponding mounting holes 101.

[0036] Specifically, the angles between adjacent first magnets 111 and adjacent second magnets 121 are both 60°, the angle between the first magnet 111 and the adjacent second magnet 121 is 30°, the distance from the center of the first magnet 111 to the nearest end of the array carrier 1 is greater than the radius of the first magnet 111, and the distance from the center of the first magnet 111 to the nearest end of the array carrier 1 is 5.5 mm.

[0037] In this embodiment, the outward magnetic poles of holes 11-16 are N, S, N, S, N, S, respectively, the outward magnetic poles of holes 31-36 are S, N, S, N, S, N, respectively, and the outward magnetic poles of holes 21-26 are all N. In this way, the magnetic field of each N pole facing outward is obviously brush-shaped, and the polishing range is larger. The brush-shaped magnetic fields of multiple N poles are continuous "S"-shaped distribution when viewed from the side of the array carrier. When the array rotates one circle, the number of times and intensity of each point on any 30mm long line segment outside the carrier parallel to the axial direction of the array carrier 1 is crossed by the magnet are consistent, making the magnetorheological polishing more uniform and sufficient, and improving the efficiency and ability of the magnetorheological polishing.

[0038] like Figure 7 As shown, this embodiment makes full use of the excellent magnetic properties of NdFeB, so that the effective polishing distance of the magnetic field array reaches 6 mm, and the magnetic induction intensity there is above 0.61 T, which is much higher than the magnetic field magnetic induction intensity generated by the Halbach array.

[0039] To ensure that the array carrier 1 can be driven by the rotating shaft 2, the rotating shaft 2 is fixed in the array carrier 1 by a pin 21. Specifically, two first through holes 102 and one second through hole 103 are provided on the side of the array carrier 1, and the axes of the first through holes 102 and the second through holes 103 are perpendicular to each other. The rotating shaft 2 is provided with a plug hole 201 corresponding to the first through hole 102 and the second through hole 103, and the rotating shaft 2 is fixed to the array carrier 1 by three pins 21 passing through the corresponding first through holes 102 and the second through holes 103. The centers of the two first through holes 102 are collinear with the center lines of the two rows of edge magnet groups 11 respectively. The second through hole 103 is provided at the center of the side of the array carrier 1, and its center is collinear with the center line of the middle magnet group 12.

[0040] When drilling, a first through hole 102 and a second through hole 103 are drilled on the side of the array carrier 1. In this embodiment, the two first through holes 102 are respectively located on both sides of the hole 21, and the centers of the three circles are on the same vertical line. One end of one first through hole 102 is located between the hole 11 and the hole 12, and the other end is located between the hole 14 and the hole 15; another first through hole 102 is located between the hole 31 and the hole 32, and the other end is located between the hole 34 and the hole 35; one end of the second through hole 103 is located between the hole 13 and the hole 33, and the other end is located between the hole 16 and the hole 36. The apertures of the first through hole 102 and the second through hole 103 are 2 mm and the depth is 30 mm.

[0041] In order to install the shaft 2, a hole with a diameter of 7mm and a depth of 30mm is drilled in the center of the array carrier 1. The plug holes 201 corresponding to the two first through holes 102 are drilled on the side of the shaft 2. The two plug holes 201 are 5.5mm and 24.5mm away from the ends of the shaft 2 respectively. Then the shaft 2 is rotated 90° and the plug holes 201 corresponding to the second through holes 103 are drilled. The distance from the plug holes 201 to the same end is 15mm. The diameters of the three plug holes 201 are all 2mm and the hole depths are all 7mm. During installation, the end of the shaft 2 drilled with the plug holes 201 is inserted into the center hole of the array carrier 1 so that the corresponding through holes correspond to the corresponding plug holes. Then the pin 21 is inserted to connect the array carrier 1 to the shaft 2.

[0042] After the magnet, the rotating shaft 2 and the pin 21 are sequentially installed into the array carrier 1, the outer cover 3 heated by the water bath is rotated and put into the entire array carrier 1, and the assembly is completed after the magnetic field array is completely cooled. The Curie temperature (magnet magnetic field failure temperature) of NdFeB is as high as 300°C, while the water bath heating is only below 100°C, so the above operation will not cause NdFeB demagnetization.

[0043] In summary, this embodiment makes full use of the excellent magnetic properties of NdFeB, so that the effective polishing distance of the magnetic field array reaches 6mm, and the magnetic induction intensity at this location is above 0.61T, which is much higher than the magnetic field magnetic induction intensity generated by the Halbach array, and the magnetic field of each N pole facing outward is obviously brush-shaped, and the brush-shaped magnetic fields of multiple N poles are continuous "S"-shaped distribution when viewed from the side of the array carrier 1. When the array rotates one circle, the number and intensity of each 30mm long line segment outside the carrier parallel to the axial direction of the array carrier 1 is consistent, making the magnetorheological polishing more uniform and sufficient, and improving the efficiency and capacity of the magnetorheological polishing.

[0044] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0045] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A magnetic field array polishing device, characterized in that: include: An array carrier, wherein two rows of edge magnet groups and one row of middle magnet groups are arranged on the side of the array carrier, the two rows of edge magnet groups are respectively arranged at the two ends of the side of the array carrier, the middle magnet group is arranged in the middle of the side of the array carrier, the first magnets on the two rows of edge magnet groups and the second magnets on the one row of middle magnet group are cylindrical magnets of the same size, the outward magnetic poles of adjacent first magnets in the same row are opposite, the outward magnetic poles of two first magnets in the same axial direction are opposite, the outward magnetic poles of the second magnets are both N poles, and the second magnets on the middle magnet group and the first magnets on the edge magnet group are arranged alternately; A rotating shaft, one end of which is inserted into the bottom of the array carrier, and the other end of which extends out of the array carrier, and the rotating shaft is connected to an external output source to drive the array carrier to rotate; A jacket is provided on the outer side of the array carrier.

2. The magnetic field array polishing device according to claim 1, characterized in that: The side surface of the array carrier is provided with mounting holes corresponding to the first magnet and the second magnet.

3. The magnetic field array polishing device according to claim 1, characterized in that: The included angles between adjacent first magnets and adjacent second magnets are both 60°, and the included angle between the first magnet and adjacent second magnet is 30°.

4. The magnetic field array polishing device according to claim 1, characterized in that: The distance from the center of the first magnet to the nearest end of the array carrier is greater than the radius of the first magnet.

5. The magnetic field array polishing device according to claim 4, characterized in that: The radius of the first magnet is 4 mm, and the distance from the center of the first magnet to the nearest end of the array carrier is 5.5 mm.

6. The magnetic field array polishing device according to claim 5, characterized in that: The array carrier is an aluminum alloy cylinder with a diameter of 30 mm and a height of 30 mm.

7. The magnetic field array polishing device according to any one of claims 1 to 6, characterized in that: The rotating shaft is fixed in the array carrier through a pin.

8. The magnetic field array polishing device according to claim 7, characterized in that: Two first through holes and one second through hole are arranged on the side of the array carrier, the axes of the first through hole and the second through hole are perpendicular to each other, and the rotating shaft is provided with insertion holes corresponding to the first through hole and the second through hole, and the rotating shaft is fixed to the array carrier by three pins passing through the corresponding first through hole and the second through hole.

9. The magnetic field array polishing device according to claim 8, characterized in that: The centers of the two first through holes are respectively collinear with the center lines of the two rows of edge magnet groups.

10. The magnetic field array polishing device according to claim 9, characterized in that: The second through hole is arranged at the center of the side surface of the array carrier, and the center of the second through hole is colinear with the center line of the middle magnet group.

Images