Magnetorheological polishing device and polishing method

Abstract

The invention belongs to the technical field of magneto-rheological polishing, and particularly relates to a magneto-rheological polishing device and a polishing method. The magnetorheological polishing device comprises a sleeve made of a non-magnetic material and fixedly arranged, a magnetic piece capable of generating a magnetic field, a first driving assembly connected with a workpiece and used for driving the workpiece to rotate and a second driving assembly connected with the magnetic piece, and the sleeve is provided with a polishing hole used for containing the workpiece. A polishing medium is arranged between the outer surface of the workpiece and the inner wall of the polishing hole, and the second driving assembly is used for driving the magnetic part to reciprocate in the length direction of the sleeve so as to generate a gradient magnetic field on the polishing medium. The magneto-rheological polishing device can polish the roller mold, and meanwhile the structure of the magneto-rheological polishing device is simplified.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic flow polishing, and in particular relates to a magnetorheological polishing device and a polishing method. Background Art

[0002] Magnetorheological finishing (MRF) is a comprehensive technology formed by applying electromagnetic theory, fluid mechanics, analytical chemistry, etc. to optical surface processing. Magnetic polishing is used in various industries, such as aviation, automobile, electronics, machinery, medical equipment, etc., to improve the surface finish and hardness of materials and increase corrosion resistance.

[0003] Magnetorheological fluid is a suspension composed of magnetic particles, base liquid and stabilizer. Magnetorheological fluid has magnetorheological effect. Under the action of magnetic field, it can achieve reversible conversion between solid and liquid phases within 1ms. Magnetorheological effect means that magnetorheological fluid is a flowable liquid when there is no magnetic field, but under the action of strong magnetic field, its rheological properties change dramatically, showing solid-like properties, and restore its flow characteristics when the magnetic field is removed. Magnetorheological polishing technology uses the rheology of magnetorheological polishing fluid in a gradient magnetic field, and the multiple flexible "small grinding heads" with viscoplasticity formed have rapid relative motion with the workpiece, so that the workpiece surface is subjected to great shear force, so that the material on the workpiece surface is removed.

[0004] However, the existing magnetorheological polishing device has a complex structure and is inconvenient to use. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a magnetorheological polishing device, aiming to solve the problem of how to polish a workpiece and simplify the structure of the magnetorheological polishing device.

[0006] To achieve the above purpose, the technical solution adopted in this application is: In a first aspect, a magnetorheological polishing device is provided for polishing a workpiece, the magnetorheological polishing device comprising: a sleeve made of non-magnetic material and fixedly arranged, a magnetic part capable of generating a magnetic field, a first driving component connected to the workpiece and used to drive the workpiece to rotate, and a second driving component connected to the magnetic part, the sleeve having a polishing hole for accommodating the workpiece, a polishing medium being arranged between the outer surface of the workpiece and the inner wall of the polishing hole, the second driving component being used to drive the magnetic part to reciprocate along the length direction of the sleeve to generate a gradient magnetic field on the polishing medium.

[0007] In some embodiments, the magnetic member has a polished through hole, and the sleeve passes through the polished through hole.

[0008] In some embodiments, the magnetic member is a first magnet in a ring shape, and the magnetization direction of the magnetic member is radial magnetization.

[0009] In some embodiments, the magnetic member is an excitation coil.

[0010] In some embodiments, the first driving assembly includes a first driver, an active abutment joint connected to the first driver, and a rotatably arranged driven abutment joint, wherein the active abutment joint and the driven abutment joint respectively abut against opposite ends of the workpiece.

[0011] In some embodiments, the workpiece is provided with a positioning through hole, and the driven abutment head and the active abutment head respectively abut against the opening edges of the two ends of the positioning through hole.

[0012] In some embodiments, the driven abutment joint is provided with an avoidance through hole connected to the positioning through hole, the first driving component also includes a positioning screw and a second magnet screwed on the positioning screw, one end of the positioning screw is fixedly arranged, the other end of the positioning screw passes through the avoidance through hole and is located in the positioning through hole, and the second magnet is located in the positioning through hole and rotates synchronously with the workpiece.

[0013] In some embodiments, the second drive assembly includes a rotatably arranged guide screw, a guide nut threadedly connected to the guide screw, and a second driver for driving the guide screw to rotate, and the magnetic member is connected to the guide nut.

[0014] In some embodiments, the magnetorheological polishing device further comprises a bracket for fixing the sleeve, wherein two brackets are arranged at intervals and are respectively located at two ends of the sleeve.

[0015] In a second aspect, a polishing method is provided, which uses the magnetorheological polishing device, and the polishing method comprises the following steps: Prepare a sleeve, a workpiece, a magnetic member, a first drive assembly and a second drive assembly, and fix the sleeve; Connecting the workpiece to the first driving assembly and placing the workpiece in the polishing hole; Placing a polishing medium between the workpiece and the inner wall of the polishing hole, and causing the first driving assembly to drive the workpiece to rotate in the polishing hole; The second driving assembly drives the magnetic member to reciprocate along the length direction of the sleeve so that the polishing medium polishes the workpiece.

[0016] The beneficial effect of the present application is that by placing the workpiece in the sleeve and arranging the polishing medium between the outer surface of the workpiece and the inner wall of the polishing hole, the first driving component drives the roller mold to rotate in the polishing hole, and the second driving component drives the magnetic part to move linearly along the axial direction of the sleeve, so that the polishing medium produces a magnetorheological effect, and multiple small grinding heads in the polishing medium can act on the surface of the rotating roller mold, thereby polishing the surface of the roller mold. The structure is simple, and the structure of the magnetorheological polishing device is simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or exemplary technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the magnetorheological polishing device provided in an embodiment of the present application; Figure 2 yes Figure 1 A schematic cross-sectional view of a magnetorheological polishing device along the sliding direction of a magnetic member; Figure 3 is a schematic diagram of the three-dimensional structure of a magnetorheological polishing device provided in another embodiment of the present application; Figure 4 yes Figure 3 A schematic cross-sectional view of a magnetorheological polishing device along the sliding direction of a magnetic member; Figure 5 It is a schematic flow chart of a polishing method provided in yet another embodiment of the present application.

[0019] Among them, the reference numerals in the figure are: 100, magnetorheological polishing device; 10, sleeve; 20, magnetic member; 30, first drive assembly; 31, first driver; 32, active abutment; 33, driven abutment; 34, positioning screw; 35, second magnet; 40, second drive assembly; 41, second driver; 42, guide screw; 43, guide nut; 101, roller mold; 102, positioning through hole; 11, polishing hole; 70, bracket; 61, sealing cover; 21, polishing through hole; DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present application.

[0021] It should be noted that when a component is referred to as being "fixed on" or "disposed on" another component, it may be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it may be directly or indirectly connected to the other component. The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances. The terms "first" and "second" are only used for the purpose of convenience of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0022] See also Figures 1 to 4 The embodiment of the present application provides a magnetorheological polishing device 100, which can polish a workpiece. In the embodiment of the present application, the workpiece is a roller mold 101, and the overall shape of the roller mold 101 is cylindrical. In other embodiments, the workpiece can also be other shapes, which can be selected according to actual conditions and are not limited here.

[0023] See also Figures 1 to 4 The magnetorheological polishing device 100 includes: a sleeve 10 made of non-magnetic material and fixedly arranged, a magnetic part 20 capable of generating a magnetic field, a first drive assembly 30 connected to a workpiece and used to drive the workpiece to rotate, and a second drive assembly 40 connected to the magnetic part 20. It can be understood that the non-magnetic material can be plastic or quartz glass. In this embodiment, the sleeve 10 is made of hard plastic. The sleeve 10 made of non-magnetic material can avoid interfering with the magnetic field generated by the magnetic part 20, so that the magnetic field generated by the magnetic part 20 can fully act on the polishing medium. The polishing medium can be a magnetorheological fluid or a magnetic abrasive powder. The magnetorheological fluid is a suspension composed of magnetic particles, a base liquid and a stabilizer. The magnetic abrasive powder can be a magnetic polishing composite powder. The polishing medium can produce a rheological effect in a gradient magnetic field, so that the roller mold 101 can be polished.

[0024] The sleeve 10 has a polishing hole 11 for receiving a workpiece, and a polishing medium is arranged between the outer surface of the workpiece and the inner wall of the polishing hole 11. The second driving assembly 40 is used to drive the magnetic member 20 to reciprocate along the length direction of the sleeve 10 to generate a gradient magnetic field on the polishing medium. Figures 1 to 4It can be understood that when the polishing medium is magnetic abrasive powder, when the magnetic part 20 is moving, due to the effect of the magnetic field of the magnetic part 20, part of the magnetic abrasive powder will move with the magnetic part 20, thereby polishing the surface of the rotating roller mold 101. Compared with magnetorheological fluid, the friction resistance of the magnetic abrasive powder to the roller mold 101 is smaller, and the roller mold 101 can obtain a higher rotation speed, thereby improving the polishing efficiency and polishing quality.

[0025] See also Figures 1 to 4 The magnetorheological polishing device 100 provided in the embodiment of the present application places the workpiece in the sleeve 10 and sets the polishing medium between the outer surface of the workpiece and the inner wall of the polishing hole 11. The first driving component 30 drives the roller mold 101 to rotate in the polishing hole 11, and the second driving component 40 drives the magnetic component 20 to move linearly along the axial direction of the sleeve 10, so that the polishing medium produces a magnetorheological effect. Multiple small grinding heads in the polishing medium can act on the surface of the rotating roller mold 101, thereby polishing the surface of the roller mold 101. The structure is simple, and the structure of the magnetorheological polishing device 100 is simplified.

[0026] See also Figures 1 to 4 Alternatively, magnetorheological polishing has the advantages of high removal efficiency, high polishing accuracy and low surface damage. Under the action of a controllable magnetic field, the magnetic abrasive powder will form countless small grinding heads according to the magnetic field, and each small grinding head can polish the surface of the workpiece to achieve an efficient removal effect. The precision of magnetic flow polishing can reach the nanometer level, and while ensuring high polishing accuracy, the surface of the workpiece will not be damaged, and a higher surface quality can be obtained.

[0027] Optionally, the sliding direction of the magnetic member 20 is as follows: Figure 2 and Figure 4 shown.

[0028] It is understandable that the roller mold 101 can be completely accommodated in the polishing hole 11 as a whole, so that the entire outer surface thereof can be polished to improve the comprehensiveness of the polishing.

[0029] See also Figures 1 to 4 It can be understood that the length direction of the sleeve 10 and the moving direction of the magnetic member 20 are the same, and they can be arranged in the vertical direction or in the horizontal direction. There is no limitation here and it can be selected according to the actual situation.

[0030] Optionally, the magnetic member 20 may at least partially surround the sleeve 10 along the circumference of the sleeve 10 to generate a gradient magnetic field for the polishing medium.

[0031] See also Figures 1 to 4In some embodiments, the magnetic member 20 has a polished through hole 21, and the magnetic member 20 slides outside the sleeve 10 through the polished through hole 21. The outer surface of the sleeve 10 does not contact the hole wall of the polished through hole 21, which is conducive to the linear sliding of the magnetic member 20.

[0032] Optionally, through the polishing through hole 21, the magnetic part can completely surround the sleeve 10 along the circumference of the sleeve 10, and the magnetic part 20 can slide linearly on the outside of the sleeve 10, so that the polishing media at the corresponding positions of the sleeve 10 are all in the gradient magnetic field, ensuring that the magnetic field of the magnetic part 20 is distributed along the circumference of the sleeve 10, so that the circumferential side surfaces of the corresponding positions of the roller mold 101 are all in contact with the polishing media that produces the magnetorheological effect, thereby improving the polishing effect and polishing efficiency.

[0033] See also Figures 1 to 4 In some embodiments, the magnetic member 20 is a first magnet and is in a ring shape, and the magnetization direction of the magnetic member 20 is radial magnetization.

[0034] The first magnet may be a permanent magnet, a constant magnet or a static magnet, which is not limited here and can be selected according to actual conditions.

[0035] Optionally, radial magnetization can make the gradient magnetic field fully act on the polishing medium, and the magnetic field can be uniformly applied around the sleeve 10, which is beneficial to the effective polishing of the workpiece by the polishing medium.

[0036] See also Figures 1 to 4 In some embodiments, the magnetic member 20 is an excitation coil, which is connected to an AC power source so that it can generate a magnetic field in a conductive state to act on the polishing medium.

[0037] Optionally, the intensity of the magnetic field can be adjusted by controlling the current of the excitation coil, thereby adapting to workpieces and occasions with different polishing requirements.

[0038] See also Figures 1 to 4 In some embodiments, the first driving assembly 30 includes a first driver 31, an active abutment joint 32 connected to the first driver 31, and a driven abutment joint 33 that is rotatably arranged, and the active abutment joint 32 and the driven abutment joint 33 respectively abut against opposite ends of the workpiece. The first driver 31 may be a servo motor that can provide rotational power to the active abutment joint 32.

[0039] See also Figures 1 to 4Optionally, the active abutment joint 32 and the driven abutment joint 33 can extend into the polishing hole 11 from both ends of the sleeve 10 respectively, and abut and connect to the two ends of the roller mold 101 respectively, the active abutment joint 32 can be connected to the output shaft of the first driver 31 through a coupling, and the driven abutment joint 33 can be fixed and rotatably set through a bearing, and the active abutment joint 32 and the driven abutment joint 33 press the roller mold 101 toward each other, so that the first driver 31 drives the active abutment joint 32, the roller mold 101 and the driven abutment joint 33 to rotate synchronously.

[0040] See also Figures 1 to 4 In some embodiments, the roller mold 101 is provided with a positioning through hole 102 , and the driven abutment joint 33 and the active abutment joint 32 abut against the opening edges of the positioning through hole 102 at opposite ends respectively.

[0041] Optionally, both the active abutment joint 32 and the driven abutment joint 33 partially extend into the positioning through hole 102 to connect and position the roller mold 101, thereby improving the stability of the rotation of the roller mold 101 during the polishing process.

[0042] See also Figure 3 to Figure 4 Optionally, the sleeve 10 is cylindrical and opened at both ends. A sealing cover 61 can be provided at both openings of the sleeve 10 to seal the polishing hole 11. The sealing cover 61 is provided with a sealing hole, and the active abutment joint 32 and the driven abutment joint 33 respectively pass through the two sealing holes and extend into the polishing hole 11.

[0043] Optionally, the abutment between the active abutment joint 32 and the edge of the positioning through hole 102, and the abutment between the driven abutment joint 33 and the edge of the positioning through hole 102 are also sealed, for example, by providing a rubber sealing ring to prevent magnetic abrasive powder or magnetorheological fluid from entering the positioning through hole 102.

[0044] See also Figure 1 to Figure 2 In some embodiments, the driven abutment joint 33 is provided with an avoidance hole connected to the positioning hole 102. The first driving assembly 30 also includes a positioning screw 34 and a second magnet 35 screwed on the positioning screw 34. One end of the positioning screw 34 is fixedly arranged, and the other end of the positioning screw 34 passes through the avoidance hole and is located in the positioning hole 102. The second magnet 35 is located in the positioning hole 102 and rotates synchronously with the workpiece.

[0045] The second magnet 35 is magnetized radially, and may be a permanent magnet, a constant magnet or a static magnet, which is not limited here and can be selected according to actual conditions.

[0046] See also Figure 1 to Figure 2Optionally, the positioning screw 34 is provided with an external thread, and the second magnet 35 is provided with a threaded hole adapted to the positioning screw 34. The cross-sectional shape of the second magnet 35 can be a polygon, such as a quadrilateral. The cross-sectional shape of the positioning through hole 102 can also be a polygon, such as a quadrilateral. The cross-sectional shape of the second magnet 35 is adapted to the cross-sectional shape of the positioning through hole 102, thereby preventing the second magnet 35 from rotating relative to the sleeve 10, so that the sleeve 10 can drive the second magnet 35 to rotate synchronously, and at the same time, the second magnet 35 slides along the axial direction of the positioning screw 34.

[0047] See also Figure 1 to Figure 2 Optionally, the second magnet 35 slides along the axial direction of the positioning screw 34 at the same time, so that the corresponding polishing medium undergoes a rheological effect. In this way, under the combined action of the magnetic member 20 and the second magnet 35, the magnetic field intensity acting on the polishing medium is increased, the effective polishing area per unit time is increased, and the polishing efficiency of the roller mold is improved.

[0048] See also Figure 1 to Figure 2 Optionally, when the polishing medium is magnetic abrasive powder, the magnetic abrasive powder will form many small grinding heads according to the magnetic field of the magnetic member 20 and the second magnet 35. Since the second magnet 35 is located inside the roller mold 101, more small grinding heads can be adsorbed and act on the side surface of the roller mold 101, thereby improving the polishing quality and polishing efficiency.

[0049] Optionally, the magnetic member 20 and the second magnet 35 may move in the same direction and synchronously, and the magnetic member 20 and the second magnet 35 act on the polishing medium together.

[0050] See also Figure 1 to Figure 2 Optionally, the magnetic member 20 and the second magnet 35 can move in opposite directions, that is, the moving directions of the two are opposite, so that the magnetic member 20 and the second magnet 35 act on different polishing media respectively to polish different positions of the roller mold 101, thereby improving the polishing efficiency.

[0051] It is understandable that after the second magnet 35 is moved into position, the moving direction of the second magnet 35 along the positioning screw 34 can be changed by changing the rotation direction of the drum mold, thereby repeatedly polishing the roller mold 101.

[0052] See also Figure 1 to Figure 2 In some embodiments, the second driving assembly 40 includes a rotatable guide screw 42, a guide nut 43 threadedly connected to the guide screw 42, and a second driver 41 for driving the guide screw 42 to rotate, and the magnetic member 20 is connected to the guide nut 43. The second driver 41 can also be a servo motor.

[0053] Optionally, the roller mold 101 is cylindrical, the length direction of the guide screw 42 is parallel to the length direction of the roller mold 101, one end of the guide screw 42 is connected to the rotating shaft of the second driver 41, and the other end of the guide screw 42 is rotatably arranged through a bearing, so that the rotational motion of the guide screw 42 can be converted into the linear movement of the magnetic member 20. By changing the rotation direction of the guide screw 42, the movement direction of the magnetic member 20 can be changed.

[0054] See also Figures 1 to 4 In some embodiments, the magnetorheological polishing device 100 further includes a bracket 70 for fixing the sleeve 10 , and two brackets 70 are arranged at intervals, and the two brackets 70 are respectively located at two ends of the sleeve 10 .

[0055] Optionally, the bracket 70 is provided with fixing holes, and the two ends of the sleeve 10 are respectively located in the two fixing holes.

[0056] See also Figure 5 The present application also proposes a polishing method, which is implemented using a magnetorheological polishing device 100. The polishing method includes the following steps: S1: prepare the sleeve 10, the roller mold 101, the magnetic member 20, the first drive assembly 30 and the second drive assembly 40, and fix the sleeve 10; S2: Connect the roller mold 101 to the first driving assembly 30, and place the roller mold 101 in the polishing hole 11; S3: placing a polishing medium between the roller mold 101 and the inner wall of the polishing hole 11, and causing the first driving assembly 30 to drive the roller mold 101 to rotate in the polishing hole 11; S4: The second driving assembly 40 drives the magnetic member 20 to reciprocate along the length direction of the sleeve 10 so that the polishing medium polishes the roller mold 101 .

[0057] It is understandable that a workpiece of any shape can be placed in the polishing hole 11 to be polished, thereby increasing the application scope of the magnetorheological polishing device 100 and achieving surface polishing of an ultra-precision roller mold 101 with a surface roughness of less than 0.02 μm.

[0058] The above are only optional embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A magnetorheological polishing device for polishing a workpiece, characterized in that: The magnetorheological polishing device includes: a sleeve made of non-magnetic material and fixedly arranged, a magnetic part capable of generating a magnetic field, a first driving component connected to the workpiece and used to drive the workpiece to rotate, and a second driving component connected to the magnetic part. The sleeve has a polishing hole for accommodating the workpiece, and a polishing medium is arranged between the outer surface of the workpiece and the inner wall of the polishing hole. The second driving component is used to drive the magnetic part to reciprocate along the length direction of the sleeve to generate a gradient magnetic field on the polishing medium.

2. The magnetorheological polishing device according to claim 1, characterized in that: The magnetic member has a polished through hole, and the magnetic member is slidably sheathed on the sleeve through the polished through hole.

3. The magnetorheological polishing device according to claim 2, characterized in that: The magnetic component is a first magnet and is in a circular ring shape, and the magnetization direction of the magnetic component is radial magnetization.

4. The magnetorheological polishing device according to claim 2, characterized in that: The magnetic component is an excitation coil.

5. The magnetorheological polishing device according to any one of claims 1 to 4, characterized in that: The first driving assembly includes a first driver, an active abutment joint connected to the first driver, and a rotatably arranged driven abutment joint, wherein the active abutment joint and the driven abutment joint abut against opposite ends of the workpiece respectively.

6. The magnetorheological polishing device according to claim 5, characterized in that: The workpiece is provided with a positioning through hole, and the driven abutment head and the active abutment head respectively abut against the opening edges of the two ends of the positioning through hole.

7. The magnetorheological polishing device according to claim 6, characterized in that: The driven abutment joint is provided with an avoidance through hole connected to the positioning through hole, the first driving component also includes a positioning screw and a second magnet screwed on the positioning screw, one end of the positioning screw is fixedly arranged, the other end of the positioning screw passes through the avoidance through hole and is located in the positioning through hole, the second magnet is located in the positioning through hole and rotates synchronously with the workpiece.

8. The magnetorheological polishing device according to any one of claims 1 to 4, characterized in that: The second driving assembly includes a rotatably arranged guide screw, a guide nut threadedly connected to the guide screw, and a second driver for driving the guide screw to rotate, and the magnetic member is connected to the guide nut.

9. The magnetorheological polishing device according to any one of claims 1 to 4, characterized in that: The magnetorheological polishing device also includes a bracket for fixing the sleeve, two of the brackets are arranged at intervals, and the two brackets are respectively located at two ends of the sleeve.

10. A polishing method, using the magnetorheological polishing device according to any one of claims 1 to 9, characterized in that: The polishing method comprises the following steps: Prepare a sleeve, a workpiece, a magnetic member, a first drive assembly and a second drive assembly, and fix the sleeve; Connecting the workpiece to the first driving assembly and placing the workpiece in the polishing hole; Placing a polishing medium between the workpiece and the inner wall of the polishing hole, and causing the first driving assembly to drive the workpiece to rotate in the polishing hole; The second driving assembly drives the magnetic member to reciprocate along the length direction of the sleeve so that the polishing medium polishes the workpiece.

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