A magnetorheological polishing device and method for a hemispherical harmonic oscillator based on an irregularly shaped permanent magnet polishing head.

Abstract

This invention provides a magnetorheological polishing device and method for hemispherical resonators based on irregularly shaped permanent magnet polishing heads, belonging to the field of ultra-precision polishing. It addresses the problem of low efficiency in existing magnetorheological polishing of hemispherical resonators using small ball heads. The device includes a workpiece spindle and a magnetorheological fluid circulation device mounted on X-axis and Y-axis linear motion platforms, and a C-axis rotary table, a U-axis micro-displacement platform, and a polishing spindle mounted on the Z-axis linear motion platform. The polishing spindle uses irregularly shaped permanent magnet polishing heads (one for the inner surface and one for the outer surface) to polish the hemispherical resonators on the workpiece spindle. This invention provides a foundation for rapid batch processing of hemispherical resonators; the irregularly shaped permanent magnet polishing head has a simple and reliable structure, strong applicability, and can be used on magnetorheological polishing machine tools with different structures.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of ultra-precision polishing processing, in particular to a hemispherical resonator magnetorheological polishing device and method based on a special-shaped permanent magnetic polishing head. BACKGROUND

[0002] The hemispherical resonator gyro is currently the most precise solid-state vibration gyro and is regarded as a disruptive technology, and is the most likely gyro to be on a par with the optical gyro or even replace the optical gyro in the future. The hemispherical resonator gyro can meet the development needs of a new generation of inertial devices for long-time navigation, and has the advantages of ultra-high precision, high reliability and long service life. The core component of the hemispherical resonator gyro is a resonator, which is a thin-walled hemispherical shell. Under the action of a force electrode, a standing wave is formed due to flexural deformation. The Coriolis effect of the standing wave under external rotation excitation will cause the precession of the vibration mode. The angular velocity can be measured by detecting the vibration mode information through a pickup electrode.

[0003] The processing technology of the resonator includes blank forming and precision grinding, polishing and chemical corrosion, mass leveling and Q value testing. The hemispherical resonator requires that the mass is uniformly distributed about the rotation axis. Once there is uneven mass distribution, the frequency splitting of the resonator will occur, and the gyro precision will be reduced. The uniform mass distribution requires a smaller surface roughness of the hemispherical shell, so the surface quality precision of the processing is very high. Therefore, magnetorheological polishing is needed to improve the surface quality precision of the hemispherical resonator and reduce the surface roughness. The current magnetorheological polishing of the hemispherical resonator adopts a small ball head polishing head, and the efficiency is low. This is because the small ball head polishing head is limited by the special-shaped structure of the hemispherical resonator. The diameter of the magnetic head is usually 3mm, which leads to a small volume of the magnetic head and a low magnetic field strength. At the same time, in the polishing process, the small ball head polishing head carries the magnetorheological fluid and is approximately in point contact with the hemispherical resonator, which leads to a small processing area and a low material removal efficiency. It takes 12 hours to polish the inner and outer spherical surfaces of the hemispherical resonator with the small ball head polishing head. SUMMARY

[0004] The technical problem to be solved by the application is:

[0005] In order to solve the problem of low efficiency of the existing hemispherical resonator magnetorheological polishing by using a small ball head polishing head.

[0006] The technical scheme adopted by the application to solve the above technical problem is:

[0007] The application provides a half-sphere harmonic resonator magnetorheological polishing device based on a special-shaped permanent magnetic polishing head, which comprises a machine tool bed body, an X-axis linear motion platform, a Y-axis linear motion platform, a Z-axis linear motion platform, a C-axis rotary table, a U-axis micro-displacement platform, a workpiece spindle, a polishing spindle, a triangular connecting frame and a workbench on the machine tool bed body, the Y-axis linear motion platform is located on the X-axis linear motion platform and is cross-stacked, and the Z-axis linear motion platform is arranged perpendicularly to the X-axis linear motion platform and the Y-axis linear motion platform to form a spatial orthogonal coordinate system.

[0008] The workbench is arranged on the Y-axis linear motion platform, and the workbench can move along the direction of the X-axis or the Y-axis with the X-axis linear motion platform and the Y-axis linear motion platform, the upper end surface of the workbench is provided with a workpiece spindle and a magnetorheological fluid circulating device, and the workpiece spindle is used for fixing a half-sphere harmonic resonator.

[0009] The Z-axis linear motion platform is connected with the C-axis rotary table through the triangular connecting frame, the C-axis rotary table is provided with the U-axis micro-displacement platform, the U-axis micro-displacement platform is provided with the polishing spindle, and the polishing spindle is used for mounting a half-sphere harmonic resonator inner spherical surface special-shaped permanent magnetic polishing head or a half-sphere harmonic resonator outer spherical surface special-shaped permanent magnetic polishing head.

[0010] The half-sphere harmonic resonator inner spherical surface special-shaped permanent magnetic polishing head and the half-sphere harmonic resonator outer spherical surface special-shaped permanent magnetic polishing head are both hollow half-ellipsoidal structures, and both are provided with a fixing rod at the bottom of the half-ellipsoidal structure.

[0011] When the polishing spindle is connected with the half-sphere harmonic resonator inner spherical surface special-shaped permanent magnetic polishing head, the inner spherical surface of the half-sphere harmonic resonator is polished, the nozzle of the magnetorheological fluid circulating device is arranged between the outer surface of the half-sphere harmonic resonator inner spherical surface special-shaped permanent magnetic polishing head and the inner surface of the half-sphere harmonic resonator, so that the magnetorheological fluid can be brought into the space between the inner spherical surface of the half-sphere harmonic resonator and the outer surface of the permanent magnetic polishing head by the polishing head.

[0012] When the polishing spindle is connected with the half-sphere harmonic resonator outer spherical surface special-shaped permanent magnetic polishing head, the outer spherical surface of the half-sphere harmonic resonator is polished, the nozzle of the magnetorheological fluid circulating device is arranged between the inner surface of the half-sphere harmonic resonator outer spherical surface special-shaped permanent magnetic polishing head and the outer surface of the half-sphere harmonic resonator, so that the magnetorheological fluid can be brought into the space between the outer spherical surface of the half-sphere harmonic resonator and the inner surface of the permanent magnetic polishing head by the polishing head.

[0013] Further, the rotation axis direction of the workpiece spindle is parallel to the Y-axis, and the rotation axis of the C-axis rotary table is parallel to the Z-axis.

[0014] Further, the included angle between the polishing spindle axis and the translation direction of the U-axis micro-displacement platform is 40°.

[0015] Further, the outer surface section of the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator is a concentric circular arc with the inner surface section of the hemispherical resonator, the end arc surface section of the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator is a concentric circular arc with the inner fillet section of the hemispherical resonator, and the wall thickness of the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator is the diameter of the end arc surface of the hemispherical resonator; the inner surface section of the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator is a concentric circular arc with the outer surface section of the hemispherical resonator, the end arc surface section of the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator is a concentric circular arc with the outer fillet section of the hemispherical resonator, and the wall thickness of the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator is the diameter of the end arc surface of the hemispherical resonator.

[0016] Further, the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator and the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator are both made of neodymium iron boron material, and the magnetic field direction is axial magnetization.

[0017] Further, the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator is a flat-bottomed semi-ellipsoidal structure, and the inner diameter of the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator is greater than the outer diameter of the hemispherical resonator; the outer diameter of the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator is less than the inner diameter of the hemispherical resonator.

[0018] Further, the gap between the outer surface section of the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator and the inner surface section of the hemispherical resonator is 80 μm, and the gap between the end arc surface section of the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator and the inner fillet section of the hemispherical resonator is 80 μm; the gap between the inner surface section of the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator and the outer surface section of the hemispherical resonator is 80 μm, and the gap between the end arc surface section of the outer spherical profiled permanent magnetic polishing head of the hemispherical resonator and the outer fillet section of the hemispherical resonator is 80 μm.

[0019] A polishing method of a hemispherical resonator magnetorheological polishing device based on a profiled permanent magnetic polishing head, comprising the following methods:

[0020] First, the inner spherical surface of the hemispherical resonator is polished,

[0021] Step one, define the direction of the hemispherical resonator support rod axis as X axis, and define the direction perpendicular to the hemispherical resonator support rod axis as Y axis; after the hemispherical resonator ultra-precision grinding is completed, control the numerical control system to make the grinding wheel move away from the hemispherical resonator along the movement direction of the machine tool Y axis and Z axis, and replace the grinding wheel clamped on the polishing spindle with the inner spherical profiled permanent magnetic polishing head of the hemispherical resonator;

[0022] Step two, tool setting for inner spherical surface polishing of the hemispherical resonator, including,

[0023] S1, by means of CCD camera and magnifying lens, the rotation of the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator is adjusted to coincide with the C-axis rotation axis, so that the rotation position of the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator remains unchanged when the hemispherical resonator rotates around the C-axis;

[0024] S2, according to the motion trail of the grinding wheel during the last grinding process, a two-dimensional drawing of the hemispherical resonator is drawn in the drawing software, the position and focal length of the industrial CCD camera are adjusted, the bottom end surface of the center support rod of the hemispherical resonator is observed, the arc end surface of the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator is slowly moved close to the bottom end surface of the center support rod of the hemispherical resonator by moving the Y-axis and Z-axis of the machine tool, and the mutual contact of the two is judged through the image of the industrial CCD camera, and the machine tool coordinates at this time are recorded as (x1, y1, z1);

[0025] S3, the arc end surface of the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator is slowly moved close to the cylindrical surface of the center support rod of the hemispherical resonator by moving the Y-axis and Z-axis of the machine tool, the mutual contact of the two is judged through the image of the industrial CCD camera, and the machine tool coordinates at this time are recorded as (x2, y2, z2), wherein x1=x2;

[0026] S4, the distance between the inner fillet of the hemispherical resonator and the bottom cylindrical surface of the center support rod is calculated as y3 in the drawing software, the inner spherical radius of the hemispherical resonator is defined as R1, the polishing gap is Δd, and the machine tool coordinates are moved to (x1, y1+y3-Δd, z2+Δd), at this time, the distance between the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator and the inner spherical surface of the hemispherical resonator is the same at each position;

[0027] S5, the workpiece spindle is manually rotated, if no collision sound is generated, it is determined that the polishing position is determined, and the tool setting is completed;

[0028] Step three: install the magnetorheological fluid circulating device and pour the magnetorheological fluid into the magnetorheological fluid circulating device, start the polishing spindle and the workpiece spindle, so that the hemispherical resonator rotates, after polishing for 10h, the polishing spindle is turned off, and the workbench is moved to move the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator away from the hemispherical resonator;

[0029] Then the outer spherical surface of the hemispherical resonator is polished,

[0030] Step four: after the inner spherical surface super-precision polishing process of the hemispherical resonator is completed, the numerical control system is controlled to move the grinding wheel away from the hemispherical resonator along the movement direction of the Y-axis and Z-axis of the machine tool, and the inner spherical special-shaped permanent magnetic polishing head of the hemispherical resonator clamped on the polishing spindle is replaced with an outer spherical special-shaped permanent magnetic polishing head of the hemispherical resonator;

[0031] Step five: the tool setting of the outer spherical surface polishing of the hemispherical resonator is performed;

[0032] S1, by means of CCD camera and magnifying lens, the rotation of the outer spherical surface of the half-harmonic oscillator is adjusted to coincide with the C-axis rotation axis, so that the rotation position of the half-harmonic oscillator outer spherical surface is kept unchanged when the half-harmonic oscillator rotates around the C-axis;

[0033] S2, according to the last time the grinding wheel motion trajectory, draw the two-dimensional drawing of the half-harmonic oscillator in the drawing software, adjust the position and focal length of the industrial CCD camera, observe the bottom end face of the half-harmonic oscillator center support rod, move the machine tool Y-axis and Z-axis to make the arc end face of the half-harmonic oscillator outer spherical surface slowly close to the bottom end face of the half-harmonic oscillator center support rod, judge the mutual contact of the two through the image of the industrial CCD camera, and record the machine tool coordinates as (x4, y4, z4) at this time;

[0034] S3, by moving the machine tool Y-axis and Z-axis, the arc end face of the half-harmonic oscillator outer spherical surface is slowly close to the bottom cylindrical surface of the half-harmonic oscillator center support rod, and the mutual contact of the two is judged through the image of the industrial CCD camera, and the machine tool coordinates at this time are recorded as (x5, y5, z5), wherein x4=x5;

[0035] S4, the distance between the inner fillet of the half-harmonic oscillator and the bottom cylindrical surface of the center support rod is calculated as y6 in the drawing software, the outer spherical radius of the half-harmonic oscillator is defined as R2, and the polishing gap is Δd, in order to avoid tool interference, firstly, the machine tool coordinates are moved to (x5, y 5， z5+R2), secondly, the machine tool coordinates are moved to (x5, y5+y6+Δd, z5+R2), and finally, the machine tool coordinates are moved to (x5, y5+y6+Δd, z5+Δd),

[0036] S5, manually rotate the workpiece spindle, if no collision sound is generated, it is determined that the polishing position is determined, and the tool setting is completed again;

[0037] Step six: start the polishing spindle and the workpiece spindle again, so that the half-harmonic oscillator rotates; after polishing for 10h, the polishing spindle is turned off, the workbench is moved, the half-harmonic oscillator outer spherical surface is moved away from the half-harmonic oscillator, and interference is avoided; the half-harmonic oscillator is taken off from the workpiece spindle, and the half-harmonic oscillator inner and outer spherical surface polishing process is completed.

[0038] Further, in step three, the preparation method of the magnetorheological fluid comprises: adding 3.5g cellulose into 500g hot water of 100℃, stirring uniformly; then adding 412g normal temperature water of 20℃, stirring uniformly; adding 168g cerium oxide polishing powder, stirring uniformly, and finally adding 2100g hydroxyl iron powder, stirring uniformly.

[0039] Further, in step three and step six, the rotation speed of the inner or outer spherical surface profiled permanent magnetic polishing head of the hemispherical resonator is 7000r / min, and the rotation speed of the rotor of the hemispherical resonator is 500r / min.

[0040] Compared with the prior art, the present application has the following advantages:

[0041] The hemispherical resonator magnetorheological polishing device and method based on the profiled permanent magnetic polishing head comprises a workpiece spindle and a magnetorheological fluid circulating device arranged on an X-axis linear motion platform and a Y-axis linear motion platform, a C-axis rotary table, a U-axis micro-displacement platform and a polishing spindle arranged on a Z-axis linear motion platform, and the polishing spindle is provided with an inner spherical surface profiled permanent magnetic polishing head and an outer spherical surface profiled permanent magnetic polishing head for polishing the hemispherical resonator on the workpiece spindle.

[0042] The hemispherical resonator magnetorheological polishing device and method based on the profiled permanent magnetic polishing head can greatly improve the polishing efficiency, the magnetic field strength is enhanced by increasing the volume of the magnet, the point contact mode of the original small ball head polishing mode is changed to the line contact mode, more magnetorheological fluid can be carried for polishing, the polishing efficiency is improved, and the foundation is provided for rapid batch processing of the hemispherical resonator; the profiled permanent magnetic polishing head has simple and reliable structure and strong applicability, and can be used for magnetorheological polishing machines of different structures. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 It is a whole structure diagram of the hemispherical resonator magnetorheological polishing device based on the profiled permanent magnetic polishing head in the embodiment of the present application.

[0044] Figure 2 It is a structure diagram of the hemispherical resonator inner spherical surface magnetorheological polishing machine in the embodiment of the present application.

[0045] Figure 3 It is a structure diagram of the hemispherical resonator inner spherical surface magnetorheological polishing in the embodiment of the present application.

[0046] Figure 4 It is a structure diagram of the hemispherical resonator inner spherical surface profiled permanent magnetic polishing head in the embodiment of the present application.

[0047] Figure 5 It is a structure diagram of the hemispherical resonator inner spherical surface profiled permanent magnetic polishing head when polishing the hemispherical resonator in the embodiment of the present application.

[0048] Figure 6 It is a structure diagram of the hemispherical resonator outer spherical surface magnetorheological polishing machine in the embodiment of the present application.

[0049] Figure 7Structure diagram of the outer spherical surface magnetorheological polishing of the hemispherical resonator in the embodiment of the present application;

[0050] Figure 8 Structure diagram of the outer spherical surface special-shaped permanent magnetic polishing head of the hemispherical resonator in the embodiment of the present application;

[0051] Figure 9 Structure diagram of the outer spherical surface special-shaped permanent magnetic polishing head of the hemispherical resonator in the embodiment of the present application;

[0052] Figure 10 Sectional magnetic flux simulation diagram of the special-shaped permanent magnetic polishing head in the embodiment of the present application.

[0053] Explanation of reference numerals:

[0054] 1, X-axis linear motion table; 2, Y-axis linear motion table; 3, workpiece spindle; 4, U-axis micro-displacement platform; 5, Z-axis linear motion table; 6, magnetorheological fluid recovery device; 7, magnetorheological fluid nozzle; 8, hemispherical resonator inner spherical surface special-shaped permanent magnetic polishing head; 9, polishing spindle; 10, hemispherical resonator outer spherical surface special-shaped permanent magnetic polishing head; 11, workbench; 12, triangular connecting frame; 13, C-axis rotary table. DETAILED DESCRIPTION

[0055] In the description of the present application, it should be explained that the terms such as "upper", "lower", "front", "rear", "left", "right" and the like in the embodiments indicate the position relationship based on the position relationship of the drawings in the description, and do not represent that the indicated elements and devices must be operated according to the specific position and limited operation and method, structure in the description, and the like. Such positional terms do not constitute a limitation on the present application.

[0056] In the description of the present application, it should be explained that the terms "first", "second", "third" mentioned in the embodiments of the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second", "third" can explicitly or implicitly include one or more features.

[0057] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings.

[0058] Specific implementation scheme one: combined with Figures 1 to 9As shown, the application provides a kind of based on special-shaped permanent magnet polishing head's hemispherical resonator magnetic fluid polishing device, including machine bed and X-axis linear motion platform 1 on machine bed, Y-axis linear motion platform 2, Z-axis linear motion platform 5, C-axis rotary table 13, U-axis micro displacement platform 4, workpiece spindle 3, polishing spindle 9, triangular connecting frame 12 and workbench 11, the Y-axis linear motion platform 2 is located on X-axis linear motion platform 1 and is cross stacked, the Z-axis linear motion platform 5 is arranged perpendicular to X-axis linear motion platform 1 and Y-axis linear motion platform 2, for forming space right-angle coordinate system;

[0059] The workbench 11 is arranged on Y-axis linear motion platform 2, and the workbench 11 can move along the direction of X-axis or Y-axis with X-axis linear motion platform 1 and Y-axis linear motion platform 2, the upper end surface of the workbench 11 is provided with workpiece spindle 3 and magnetic fluid circulating device, the workpiece spindle 3 is used to fix hemispherical resonator, and the rotation axis direction of the workpiece spindle 3 is parallel to Y-axis;

[0060] The Z-axis linear motion platform 5 is connected with C-axis rotary table 13 through triangular connecting frame 12, the C-axis rotary table 13 is provided with U-axis micro displacement platform 4, the U-axis micro displacement platform 4 is provided with polishing spindle 9, the polishing spindle 9 is used to install hemispherical resonator inner spherical surface special-shaped permanent magnet polishing head 8 or hemispherical resonator outer spherical surface special-shaped permanent magnet polishing head 10, the rotation axis of the C-axis rotary table 13 is parallel to Z-axis, and the included angle between the axis of the polishing spindle 9 and the translation direction of the U-axis micro displacement platform 4 is 40 °;

[0061] The hemispherical resonator inner spherical surface special-shaped permanent magnet polishing head 8 and the hemispherical resonator outer spherical surface special-shaped permanent magnet polishing head 10 are both hollow semi-ellipsoidal structures, and both are provided with fixing rods at the bottom of the semi-ellipsoidal structure, the outer surface section of the hemispherical resonator inner spherical surface special-shaped permanent magnet polishing head 8 and the inner surface section of the hemispherical resonator are concentric circular arcs, the end arc surface section of the hemispherical resonator inner spherical surface special-shaped permanent magnet polishing head 8 and the inner fillet section of the hemispherical resonator are concentric circular arcs, and the wall thickness of the hemispherical resonator inner spherical surface special-shaped permanent magnet polishing head 8 is the diameter of the end arc surface of the hemispherical resonator;The inner surface section of the hemispherical resonator outer spherical surface special-shaped permanent magnet polishing head 10 and the outer surface section of the hemispherical resonator are concentric circular arcs, the end arc surface section of the hemispherical resonator outer spherical surface special-shaped permanent magnet polishing head 10 and the outer fillet section of the hemispherical resonator are concentric circular arcs, and the wall thickness of the hemispherical resonator outer spherical surface special-shaped permanent magnet polishing head 10 is the diameter of the end arc surface of the hemispherical resonator;

[0062] When the polishing spindle 9 is connected with the inner spherical surface special-shaped permanent magnetic polishing head 8 of the hemispherical resonator, the inner spherical surface of the hemispherical resonator is polished, the spray head of the magnetorheological fluid circulating device is arranged between the outer surface of the inner spherical surface special-shaped permanent magnetic polishing head 8 of the hemispherical resonator and the inner surface of the hemispherical resonator, so that the magnetorheological fluid can be brought into the hemispherical resonator and the outer surface of the inner spherical surface special-shaped permanent magnetic polishing head 8 of the hemispherical resonator.

[0063] When the polishing spindle 9 is connected with the outer spherical surface special-shaped permanent magnetic polishing head 10 of the hemispherical resonator, the outer spherical surface of the hemispherical resonator is polished, the spray head of the magnetorheological fluid circulating device is arranged between the inner surface of the outer spherical surface special-shaped permanent magnetic polishing head 10 of the hemispherical resonator and the outer surface of the hemispherical resonator, so that the magnetorheological fluid can be brought into the hemispherical resonator and the inner surface of the outer spherical surface special-shaped permanent magnetic polishing head 10 of the hemispherical resonator.

[0064] The machine tool bed, the X-axis linear motion platform 1, the Y-axis linear motion platform 2, the Z-axis linear motion platform 5, the C-axis rotary table 13 and the U-axis micro displacement platform 4 used in the application are all existing devices, and details are not repeated here. Among them, the three-dimensional adjustment table can be TSD-405C of Sigma Company.

[0065] Preferably, the inner spherical surface special-shaped permanent magnetic polishing head 8 of the hemispherical resonator and the outer spherical surface special-shaped permanent magnetic polishing head 10 are both made of neodymium iron boron material, and the magnetic field direction is axial magnetization, and the cross-sectional magnetic flux simulation is as shown in the figure. Figure 10

[0066] Preferably, the outer spherical surface special-shaped permanent magnetic polishing head 10 of the hemispherical resonator is a flat-bottomed semi-ellipsoidal structure, and the inner diameter of the outer spherical surface special-shaped permanent magnetic polishing head 10 of the hemispherical resonator is greater than the outer diameter of the hemispherical resonator; the outer diameter of the inner spherical surface special-shaped permanent magnetic polishing head 8 of the hemispherical resonator is smaller than the inner diameter of the hemispherical resonator, so as to avoid touching the hemispherical resonator during polishing.

[0067] ​Preferably, the gap between the outer surface section of the inner spherical profiled permanent magnetic polishing head 8 of the hemispherical resonator and the inner surface section of the hemispherical resonator is 80 μm, the gap between the end arc surface section of the inner spherical profiled permanent magnetic polishing head 8 of the hemispherical resonator and the inner fillet section of the hemispherical resonator is 80 μm, when the inner spherical profiled permanent magnetic polishing head 8 of the hemispherical resonator and the inner spherical surface of the hemispherical resonator are tangent at the polishing position, the gap between them from large to small and then to large along the rotation direction of the inner spherical profiled permanent magnetic polishing head 8 of the hemispherical resonator, so that the magnetorheological fluid is more easily entered into the polishing gap; the gap between the inner surface section of the outer spherical profiled permanent magnetic polishing head 10 of the hemispherical resonator and the outer surface section of the hemispherical resonator is 80 μm, the gap between the end arc surface section of the outer spherical profiled permanent magnetic polishing head 10 of the hemispherical resonator and the outer fillet section of the hemispherical resonator is 80 μm, when the outer spherical profiled permanent magnetic polishing head 10 of the hemispherical resonator and the outer spherical surface of the hemispherical resonator are tangent at the polishing position, the gap between them from large to small and then to large along the rotation direction of the outer spherical profiled permanent magnetic polishing head 10 of the hemispherical resonator, so that the magnetorheological fluid is more easily entered into the polishing gap.

[0068] Preferably, the magnetorheological fluid circulating device comprises a supply peristaltic pump, a universal nozzle, a recovery peristaltic pump, a storage stirrer, a constant temperature water bath and a magnetorheological fluid recovery device 6, the storage stirrer is used for storing the magnetorheological polishing fluid, the storage stirrer and the universal nozzle are communicated through a supply silica gel hose, the supply peristaltic pump is arranged on the supply silica gel hose, the supply silica gel hose is immersed in the constant temperature water bath, the outlet of the universal nozzle is located above the magnetorheological fluid recovery device 6, the liquid collecting outlet of the magnetorheological fluid recovery device 6 is communicated with the storage stirrer through a recovery silica gel hose, the recovery peristaltic pump is arranged on the recovery silica gel hose, and a closed magnetorheological fluid circulating loop is formed. The magnetorheological fluid recovery device 6 is arranged below the hemispherical resonator. The universal nozzle has the same meaning as the magnetorheological fluid nozzle 7.

[0069] Specific embodiment two: the application provides a hemispherical resonator magnetorheological polishing method based on a profiled permanent magnetic polishing head, comprising the following steps:

[0070] First, the inner spherical surface of the hemispherical resonator is polished,

[0071] Step one, define the direction of the hemispherical resonator support rod as the X axis, and define the direction perpendicular to the hemispherical resonator support rod as the Y axis, after the hemispherical resonator ultra-precision grinding is finished, control the numerical control system to make the grinding wheel move away from the hemispherical resonator in the Y axis and Z axis movement direction by a certain distance, the distance should be convenient for the subsequent loading and unloading of the grinding wheel and the polishing head, and the grinding wheel clamped on the polishing spindle is replaced by the inner spherical profiled permanent magnetic polishing head 8 of the hemispherical resonator;

[0072] Step two, tool setting for polishing the inner spherical surface of the hemispherical resonator, including,

[0073] S1, adjust the rotation of the inner spherical profile permanent magnetic polishing head 8 of the hemispherical resonator to coincide with the C-axis rotation axis by means of the CCD camera and the magnifying lens, so that the rotation position of the polishing head remains unchanged when the inner spherical profile permanent magnetic polishing head 8 of the hemispherical resonator rotates around the C-axis;

[0074] S2, draw the two-dimensional drawing of the hemispherical resonator in the AUTO CAD drawing software according to the grinding wheel movement track during the last grinding process, adjust the position and focal length of the industrial CCD camera, observe the bottom end face of the center support rod of the hemispherical resonator, slowly move the hemispherical resonator inner spherical profile permanent magnetic polishing head 8 arc end face to the bottom end face of the center support rod of the hemispherical resonator by moving the machine tool Y-axis and Z-axis, determine the mutual contact of the two through the image of the industrial CCD camera, and record the machine coordinates at this time as (x1, y1, z1);

[0075] S3, slowly move the hemispherical resonator inner spherical profile permanent magnetic polishing head 8 arc end face to the cylindrical surface of the center support rod of the hemispherical resonator by moving the machine tool Y-axis and Z-axis, determine the mutual contact of the two through the image of the industrial CCD camera, and record the machine coordinates at this time as (x2, y2, z2), wherein x1=x2;

[0076] S4, calculate the distance between the inner fillet of the hemispherical resonator and the bottom cylindrical surface of the center support rod as y3 in the AUTO CAD drawing software, define the inner spherical radius of the hemispherical resonator as R1, and the polishing gap as Δd, move the machine coordinates to (x1, y1+y3-Δd, z2+Δd), at this time the distance between the hemispherical resonator inner spherical profile permanent magnetic polishing head 8 and the inner spherical surface of the hemispherical resonator is the same at each position;

[0077] S5, manually rotate the workpiece spindle 3, if no collision sound is generated, it is determined as the polishing position;

[0078] Step three: place the magnetorheological fluid recovery device 6 below the hemispherical resonator, connect the stirrer, supply peristaltic pump, universal bamboo joint nozzle in sequence according to the magnetorheological fluid flow direction by using silica gel hose, then connect the magnetorheological fluid recovery device 6, recovery peristaltic pump, stirrer in sequence, and place the magnetorheological fluid recovery device 6 below the universal bamboo joint nozzle, forming a closed magnetorheological fluid circulation loop;

[0079] Step four: configure the magnetorheological fluid, add 3.5g cellulose into 500g hot water at 100℃ and stir uniformly; then add 412g normal temperature water at 20℃ and stir uniformly; add 168g cerium oxide polishing powder and stir uniformly; finally add 2100g hydroxyl iron powder and stir uniformly, pour the configured magnetorheological fluid into the stirrer;

[0080] Step five: Put the MR fluid baffle around the hemispherical resonator to prevent the MR fluid from splashing during the processing, open the supply peristaltic pump and the recovery peristaltic pump, adjust the position of the bumping tube nozzle to make the MR fluid drop to the polishing head, start the polishing spindle 9 to make the polishing head rotate at 7000 r / min, and start the workpiece spindle 3 to make the hemispherical resonator rotate at 500 r / min;

[0081] Step six: After polishing for 10 h, the polishing spindle 9 is turned off, and the workbench 11 is moved to move the inner spherical special-shaped permanent magnetic polishing head 8 of the hemispherical resonator away from the hemispherical resonator;

[0082] Then the outer spherical surface of the hemispherical resonator is polished,

[0083] Step seven: After the ultra-precision polishing of the inner spherical surface of the hemispherical resonator is completed, the numerical control system is controlled to move the grinding wheel away from the hemispherical resonator along the movement directions of the machine tool Y axis and Z axis by a certain distance, which should be convenient for the subsequent loading and unloading of the outer spherical special-shaped permanent magnetic polishing head 10 of the hemispherical resonator, and the inner spherical special-shaped permanent magnetic polishing head 8 of the hemispherical resonator clamped on the polishing spindle is replaced by the outer spherical special-shaped permanent magnetic polishing head 10 of the hemispherical resonator;

[0084] Step eight: The outer spherical surface of the hemispherical resonator is polished;

[0085] S1, the rotation of the outer spherical special-shaped permanent magnetic polishing head 10 of the hemispherical resonator is adjusted to coincide with the C-axis rotation axis by means of the CCD camera and the magnifying lens, so that the rotation position of the polishing head remains unchanged when the outer spherical special-shaped permanent magnetic polishing head 10 of the hemispherical resonator rotates around the C-axis;

[0086] S2, according to the grinding wheel movement track during the last grinding processing, a two-dimensional drawing of the hemispherical resonator is drawn in the AUTO CAD drawing software, the position and focal length of the industrial CCD camera are adjusted, the bottom end surface of the center support rod of the hemispherical resonator is observed, the arc end surface of the outer spherical special-shaped permanent magnetic polishing head 10 of the hemispherical resonator is slowly approached to the bottom end surface of the center support rod of the hemispherical resonator by moving the machine tool Y axis and Z axis, the mutual contact of the two is judged through the image of the industrial CCD camera, and the machine tool coordinates at this time are recorded as (x4, y4, z4);

[0087] S3, the arc end surface of the outer spherical special-shaped permanent magnetic polishing head 10 of the hemispherical resonator is slowly approached to the bottom cylindrical surface of the center support rod of the hemispherical resonator by moving the machine tool Y axis and Z axis, the mutual contact of the two is judged through the image of the industrial CCD camera, and the machine tool coordinates at this time are recorded as (x5, y5, z5), wherein x4=x5;

[0088] S4, calculate the distance between the inner corner of the hemisphere resonator and the bottom of the center support rod in AUTO CAD drawing software, y6, define the outer spherical surface radius of the hemisphere resonator as R2, and the polishing gap as Δd, in order to avoid tool interference, first move the machine tool coordinates to (x5, y5, z5+R2), secondly move the machine tool coordinates to (x5, y5+y6+Δd, z5+R2), and finally move the machine tool coordinates to (x5, y5+y6+Δd, z5+Δd),

[0089] S5, manually rotate the workpiece spindle 3, and if no collision sound is generated, it is determined that the polishing position is correct.

[0090] Step nine: start the polishing spindle 9 again, so that the polishing head rotates at 7000r / min, and start the workpiece spindle 3, so that the hemisphere resonator rotates at 500r / min.

[0091] Step six: after polishing for 10h, turn off the polishing spindle 9, and move the workbench 11, so that the outer spherical surface special-shaped permanent magnet polishing head 10 of the hemisphere resonator moves away from the hemisphere resonator to avoid interference;

[0092] Step seven: take the hemisphere resonator off the workpiece spindle, and use deionized water, dilute hydrochloric acid and alcohol to clean the magnetic rheological fluid remaining on the surface of the small curved surface part.

[0093] Complete the polishing process of the inner and outer spherical surfaces of the hemisphere resonator.

[0094] The other combinations and connection relationships of the embodiment are the same as those of the specific embodiment one.

[0095] Although the present application is disclosed as above, the protection scope of the present application is not limited to this. The person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and these changes and modifications will fall within the protection scope of the present application.

Claims

1. A method for hemispherical resonator magneto rheological polishing based on a special-shaped permanent magnetic polishing head, characterized in that: The method is realized by using a half-sphere harmonic oscillator magnetorheological polishing device based on a special-shaped permanent magnetic polishing head, and the half-sphere harmonic oscillator magnetorheological polishing device based on the special-shaped permanent magnetic polishing head comprises a machine tool bed body, an X-axis linear motion platform (1), a Y-axis linear motion platform (2), a Z-axis linear motion platform (5), a C-axis rotary table (13), a U-axis micro-displacement platform (4), a workpiece spindle (3), a polishing spindle (9), a triangular connecting frame (12) and a worktable (11) on the machine tool bed body, the Y-axis linear motion platform (2) is located on the X-axis linear motion platform (1) and is cross-stacked, and the Z-axis linear motion platform (5) is arranged perpendicularly to the X-axis linear motion platform (1) and the Y-axis linear motion platform (2) to form a spatial orthogonal coordinate system; The worktable (11) is arranged on the Y-axis linear motion platform (2), the worktable (11) can move along the direction of the X-axis or the Y-axis with the X-axis linear motion platform (1) and the Y-axis linear motion platform (2), and the upper end surface of the worktable (11) is provided with the workpiece spindle (3) and a magnetorheological fluid circulating device, the workpiece spindle (3) is used for fixing a half-sphere harmonic oscillator; The Z-axis linear motion platform is connected with the C-axis rotary table (13) through the triangular connecting frame (12), the C-axis rotary table (13) is provided with the U-axis micro-displacement platform (4), the U-axis micro-displacement platform (4) is provided with the polishing spindle (9), and the polishing spindle (9) is used for mounting a half-sphere harmonic oscillator inner spherical surface special-shaped permanent magnetic polishing head (8) or a half-sphere harmonic oscillator outer spherical surface special-shaped permanent magnetic polishing head (10); The half-sphere harmonic oscillator inner spherical surface special-shaped permanent magnetic polishing head (8) and the half-sphere harmonic oscillator outer spherical surface special-shaped permanent magnetic polishing head (10) are both hollow half-ellipsoidal structures, and both are provided with a fixing rod at the bottom of the half-ellipsoidal structure; When the polishing spindle (9) is connected with the half-sphere harmonic oscillator inner spherical surface special-shaped permanent magnetic polishing head (8), the inner spherical surface of the half-sphere harmonic oscillator is polished, the nozzle of the magnetorheological fluid circulating device is arranged between the outer surface of the half-sphere harmonic oscillator inner spherical surface special-shaped permanent magnetic polishing head (8) and the inner surface of the half-sphere harmonic oscillator, so that the magnetorheological fluid can be brought into the space between the inner spherical surface of the half-sphere harmonic oscillator and the outer surface of the permanent magnetic polishing head by the polishing head; When the polishing spindle (9) is connected with the half-sphere harmonic oscillator outer spherical surface special-shaped permanent magnetic polishing head (10), the outer spherical surface of the half-sphere harmonic oscillator is polished, the nozzle of the magnetorheological fluid circulating device is arranged between the inner surface of the half-sphere harmonic oscillator outer spherical surface special-shaped permanent magnetic polishing head (10) and the outer surface of the half-sphere harmonic oscillator, so that the magnetorheological fluid can be brought into the space between the outer spherical surface of the half-sphere harmonic oscillator and the inner surface of the permanent magnetic polishing head by the polishing head; The rotation axis direction of the workpiece spindle (3) is parallel to the Y-axis, and the rotation axis of the C-axis rotary table (13) is parallel to the Z-axis. The outer surface section of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator is a concentric circular arc with the inner surface section of the hemispherical resonator, the end arc surface section of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator is a concentric circular arc with the inner corner section of the hemispherical resonator, and the wall thickness of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator is the diameter of the end arc surface of the hemispherical resonator; the inner surface section of the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator is a concentric circular arc with the outer surface section of the hemispherical resonator, the end arc surface section of the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator is a concentric circular arc with the outer corner section of the hemispherical resonator, and the wall thickness of the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator is the diameter of the end arc surface of the hemispherical resonator; The inner spherical special-shaped permanent magnetic polishing head (8) and the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator are both made of neodymium iron boron material, and the magnetic field direction is axial magnetization; The outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator is a flat-bottomed semi-ellipsoidal structure, and the inner diameter of the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator is greater than the outer diameter of the hemispherical resonator; the outer diameter of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator is less than the inner diameter of the hemispherical resonator; The gap between the outer surface section of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator and the inner surface section of the hemispherical resonator is 80 μm, and the gap between the end arc surface section of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator and the inner corner section of the hemispherical resonator is 80 μm; the gap between the inner surface section of the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator and the outer surface section of the hemispherical resonator is 80 μm, and the gap between the end arc surface section of the outer spherical special-shaped permanent magnetic polishing head (10) of the hemispherical resonator and the outer corner section of the hemispherical resonator is 80 μm; The method comprises the following steps: First, the inner spherical surface of the hemispherical resonator is polished, Step one, define the direction of the hemispherical resonator support rod axis as X axis, and define the direction perpendicular to the hemispherical resonator support rod axis as Y axis; after the hemispherical resonator ultra-precision grinding is completed, control the numerical control system to make the grinding wheel move away from the hemispherical resonator along the movement direction of the machine tool Y axis and Z axis, and replace the grinding wheel clamped on the polishing spindle (9) with the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator; Step two, perform the hemispherical resonator inner spherical surface polishing tool setting, including, S1, adjust the rotation of the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator to coincide with the C-axis rotation axis by means of CCD camera and magnifying lens, so that the rotation position of the polishing head remains unchanged when the inner spherical special-shaped permanent magnetic polishing head (8) of the hemispherical resonator rotates around the C-axis; S2, according to the last time the grinding wheel movement trajectory when processing, draw a two-dimensional drawing of the hemispherical resonator in the drawing software, adjust the position and focal length of the industrial CCD camera, observe the bottom end face of the hemispherical resonator center support rod, move the machine tool Y axis and Z axis to make the arc end face of the hemispherical resonator inner spherical special-shaped permanent magnet polishing head (8) slowly close to the bottom end face of the hemispherical resonator center support rod, judge the mutual contact of the two through the image of the industrial CCD camera, and record the machine tool coordinates (x1, y1, z1) at this time; S3, slowly approach the cylindrical surface of the center support rod of the hemispherical resonator by the Y-axis and Z-axis of the mobile machine, and judge the mutual contact of the two by the image of the industrial CCD camera, and record the machine coordinates at this time as (x ２ , y ２ , z ２ ), wherein x1=x ２ ; S4, calculate the distance between the inner spherical harmonic resonator and the bottom of the center support rod in the drawing software y ３ , define the inner spherical harmonic resonator radius as R1, the polishing gap as Δd, and move the machine tool coordinates to (x1, y1+y ３ -Δd, z2+Δd), at this time the inner spherical harmonic resonator and the inner spherical surface of the special-shaped permanent magnet polishing head (8) have the same distance at each position. S5, manually rotate the workpiece spindle (3), if no collision sound is generated, it is determined that the polishing position is determined, and the tool setting is completed; Step three: install the magnetic fluid circulation device and pour the magnetic fluid into the magnetic fluid circulation device, start the polishing spindle (9) and the workpiece spindle (3), so that the hemispherical resonator rotates, after polishing for 10h, the polishing spindle (9) is closed, the workbench (11) is moved, and the hemispherical resonator inner spherical special-shaped permanent magnet polishing head (8) is moved away from the hemispherical resonator; Then the hemispherical resonator outer spherical surface is polished, Step four: after the hemispherical resonator inner spherical surface super-precision polishing processing is completed, the numerical control system is controlled to move the grinding wheel away from the hemispherical resonator along the movement direction of the machine tool Y axis and Z axis, and the hemispherical resonator inner spherical special-shaped permanent magnet polishing head (8) clamped on the polishing spindle (9) is replaced by the hemispherical resonator outer spherical special-shaped permanent magnet polishing head (10); Step five: hemispherical resonator outer spherical surface polishing tool setting is performed; S1, with the help of a CCD camera and a magnifying lens, the rotation of the hemispherical resonator outer spherical special-shaped permanent magnet polishing head (10) is adjusted to coincide with the C-axis rotation axis, so that the rotation position of the polishing head remains unchanged when the hemispherical resonator outer spherical special-shaped permanent magnet polishing head (10) rotates around the C-axis; S2, according to the last time the grinding wheel movement trajectory, draw a two-dimensional drawing of the hemispherical resonator in the drawing software, adjust the position and focal length of the industrial CCD camera, observe the bottom end face of the hemispherical resonator center support rod, move the machine tool Y axis and Z axis to make the arc end face of the hemispherical resonator outer spherical surface special-shaped permanent magnet polishing head (10) slowly close to the bottom end face of the hemispherical resonator center support rod, judge the mutual contact of the two through the image of the industrial CCD camera, and record the machine tool coordinates (x ４ ,y ４ ,z ４ ) at this time; S3, slowly approach the bottom of the cylindrical surface of the center support rod of the hemispherical resonator by moving the Y-axis and Z-axis of the machine tool, and judge the mutual contact of the two through the image of the industrial CCD camera, and record the machine coordinates at this time as (x ５ ,y ５ ,z ５ ), wherein ４ =x ５ ; S4, calculate the distance between the inner corner of the hemispherical resonator and the bottom of the center support rod in the drawing software y ６ , define the outer spherical radius of the hemispherical resonator as R2, and the polishing gap as Δd, in order to avoid tool interference, first move the machine coordinates to (x ５ , y ５， z ５ + R2), secondly move the machine coordinates to (x ５ , y ５ +y ６ + Δd, z ５ + R2), and finally move the machine coordinates to (x ５ , y ５ +y ６ + Δd, z ５ + Δd), S5, manually rotate the workpiece spindle (3), if no collision sound is generated, it is determined that the polishing position is determined, and the tool setting is completed; Step six: start the polishing spindle (9) and the workpiece spindle (3) again, so that the hemispherical resonator rotates; after polishing for 10h, the polishing spindle (9) is closed, the workbench (11) is moved, and the hemispherical resonator outer spherical special-shaped permanent magnet polishing head (10) is moved away from the hemispherical resonator to avoid interference; the hemispherical resonator is removed from the workpiece spindle (3), and the hemispherical resonator inner and outer spherical surface polishing process is completed.

2. The hemispherical resonator magnetorheological polishing method based on a special-shaped permanent magnetic polishing head according to claim 1, characterized in that: The angle between the polishing spindle (9) axis and the U-axis micro-displacement platform (4) translation direction is 40°.

3. The hemispherical resonator magnetorheological polishing method based on a special-shaped permanent magnetic polishing head according to claim 2, characterized in that: In step three, the preparation method of the magnetic fluid includes: adding 3.5g cellulose into 500g 100℃ hot water, stirring uniformly; then adding 412g 20℃ normal temperature water, stirring uniformly; adding 168g cerium oxide polishing powder, stirring uniformly, and finally adding 2100g hydroxyl iron powder, stirring uniformly.

4. The hemispherical resonator magnetorheological polishing method based on a special-shaped permanent magnetic polishing head according to claim 3, characterized in that: In step three and step six, the rotating speed of the hemispherical resonator inner spherical special-shaped permanent magnet polishing head (8) or the hemispherical resonator outer spherical special-shaped permanent magnet polishing head (10) is 7000r / min, and the rotor of the hemispherical resonator is 500r / min.

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