Hemispherical resonator expansion polishing method based on rheological principle

Abstract

The application discloses a kind of based on rheological principle's hemispherical harmonic oscillator eikonal polishing method, mainly including the following steps: first hemispherical harmonic oscillator is clamped in workpiece spindle, and polishing tool is clamped in tool spindle;Again, the position of workpiece spindle and tool spindle is adjusted, the axis of workpiece spindle coincides with the axis of tool spindle, and the ball center of polishing tool coincides with the ball center of hemispherical harmonic oscillator;Then, the included angle between polishing tool axis and hemispherical harmonic oscillator axis is adjusted, and polishing tool and hemispherical harmonic oscillator form polishing assembly;Then, polishing assembly is immersed in polishing liquid, and workpiece spindle and tool spindle are started, and drive hemispherical harmonic oscillator and polishing tool rotation;Polishing liquid forms two eikonal polishing flow fields in the gap between polishing tool and hemispherical harmonic oscillator inner and outer spherical surface, to realize synchronous efficient polishing to hemispherical harmonic oscillator inner and outer spherical surface and root transition circular arc using the rheological property of polishing liquid, and the polishing efficiency is high, precision is high, surface quality is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of precision and ultra-precision machining, and particularly relates to a hemispherical resonator generating polishing method based on rheological principle. BACKGROUND

[0002] The hemispherical resonator is a core sensitive functional component of a hemispherical resonator gyroscope, and has a hemispherical shell with a center support rod. The hemispherical resonator has small size, thin wall, and is usually made of high-quality fused quartz glass. The specific service environment and working principle have very high requirements on the machining precision and surface quality of the hemispherical resonator. The high hardness and brittleness of the material, the thin wall, and the irregular spherical surface of the structure bring challenges to the realization of high-efficiency, high-quality, and low-cost batch machining of the hemispherical resonator.

[0003] The polishing methods for complex surfaces mainly include magnetorheological polishing, airbag polishing, and abrasive flow polishing. The above polishing methods generate a flexible "polishing mold" that matches the machined surface in the polishing area, and realize the controllable change of the flexibility of the "polishing mold" through air pressure, flow field, and magnetic field. However, due to the special shape of the hemispherical resonator, especially the characteristics of the large curvature and small space of the intersection area of the support rod and the inner spherical surface, the accessibility of the polishing tool is poor, and there is an interference problem between the polishing tool and the workpiece. The small polishing head / sub-aperture polishing has problems of efficiency and material removal function stability, thereby resulting in low polishing efficiency and poor surface shape precision. At present, there is still a lack of effective technical means to realize high-efficiency and precise polishing of high-quality quartz hemispherical resonators. SUMMARY

[0004] In order to overcome the above problems in the prior art, the present application provides a hemispherical resonator generating polishing method based on rheological principle, which has the advantages of high efficiency, high quality, and high precision. The hemispherical resonator generating polishing method of the present application is based on the rheological properties of the polishing liquid, and uses a polishing tool with a double-layer specific structure to replace the traditional small polishing head. The polishing tool and the workpiece form a polishing assembly in a specific way, and the inner and outer spherical surfaces and the root transition circular arc of the hemispherical resonator can be polished synchronously. The polishing precision is high, the efficiency is high, the polishing material removal is uniform, and the surface quality of the hemispherical resonator after polishing is good.

[0005] The technical scheme of the present application is as follows:

[0006] The polishing method is based on the rheological principle and uses a hemispherical resonator to perform polishing treatment by using a hemispherical resonator polishing device; the hemispherical resonator polishing device comprises a workpiece spindle, a tool spindle, a polishing tool and a deflection device; the workpiece spindle is used to clamp the hemispherical resonator to be polished and drive the hemispherical resonator to rotate; the tool spindle is used to clamp the polishing tool and drive the polishing tool to rotate; the polishing tool comprises a connecting rod; the connecting rod is provided with an inner support web and an outer support web, and the end portions of the inner support web and the outer support web are provided with lips; the tool spindle is arranged on the deflection device; the deflection device is used to drive the tool spindle to deflect by a certain angle, so that the axis of the polishing tool and the axis of the hemispherical resonator form a certain angle.

[0007] The polishing method comprises the following steps: step one, mounting the hemispherical resonator on the workpiece spindle coaxially with the workpiece spindle, and mounting the polishing tool on the tool spindle coaxially with the tool spindle; step two, adjusting the positions of the workpiece spindle and the tool spindle, so that the axis of the workpiece spindle coincides with the axis of the tool spindle, and the ball center of the polishing tool coincides with the ball center of the hemispherical resonator, and the coincident point is located on the rotation axis of the deflection device; step three, starting the deflection device to drive the tool spindle to deflect, so that the angle between the axis of the polishing tool and the axis of the hemispherical resonator is β, and a polishing assembly is formed; R1 is the outer spherical surface radius of the hemispherical resonator, D is the diameter of the central rod of the hemispherical resonator, and r is the root transition arc radius of the hemispherical resonator; at this time, the minimum gap between the outer root transition arc of the hemispherical resonator and the outer lip is d1, and the minimum gap between the inner root transition arc and the inner lip is d2; step four, constructing a polishing liquid station, immersing the polishing assembly in the polishing liquid, starting the workpiece spindle to drive the hemispherical resonator to rotate (the rotation speed can be 10-300 rpm), and starting the tool spindle to drive the polishing tool to rotate (the rotation speed can be 100-3000 rpm); at this time, the polishing tool and the hemispherical resonator rotate relatively, and the polishing liquid forms two generating polishing flow fields in the gap between the inner support web and the inner spherical surface of the hemispherical resonator and the gap between the outer support web and the outer spherical surface of the hemispherical resonator, so as to polish the inner spherical surface, the outer spherical surface and the root transition arc of the hemispherical resonator; step five, when the set polishing time T is reached, the hemispherical resonator is cleaned and taken out, and the polishing is completed.

[0008] Compared with the prior art, the hemispherical resonator expansion polishing method based on the rheological principle has the following advantages: (1) high polishing efficiency; the polishing method uses a double-layer structure polishing tool to replace the traditional small polishing head, forms a polishing assembly with the workpiece (hemispherical resonator) in a specific way, and cooperates with the polishing liquid with rheological properties to polish the inner and outer spherical surfaces and the root transition arc of the hemispherical resonator at the same time, thereby increasing the polishing area and improving the material removal efficiency of the polishing material, and the polishing efficiency is high (the polishing efficiency can be improved to within 1 hour); (2) good surface quality after polishing; the polishing method is based on the rheological effect of the polishing liquid and has the characteristics of non-contact, the material removal is mainly based on the shear action of abrasive particles and the surface of the hemispherical resonator, the normal force is small, and the brittle material can be uniformly removed without damage, so that the surface quality of the hemispherical resonator after polishing is good; (3) high face shape precision after polishing; based on the machining principle described in the application, the rotational symmetry of the hemispherical resonator is not theoretically damaged; and the polishing method only needs to be clamped once to complete the synchronous polishing of the inner and outer spherical surfaces and the root transition arc of the hemispherical resonator, so that the concentricity of the hemispherical resonator during polishing can be ensured, and the polishing precision is improved.

[0009] As an optimization, in the aforementioned hemispherical resonator expansion polishing method based on the rheological principle, the lip edge is a toothed structure. In this way, during polishing, the teeth on the lip edge will entrap a part of the polishing liquid, so that the lip edge can flow with the polishing liquid, thereby improving the polishing effect.

[0010] Further, the inner support web and the outer support web can be designed in different structural shapes. For example, the inner support web and the outer support web can be conical, cylindrical or hemispherical, and the surface is hollow. Alternatively, the inner support web includes a set of inner arc-shaped plates distributed along the circumference; the outer support web includes a set of outer arc-shaped plates distributed along the circumference. At this time, it is convenient for the polishing liquid to flow into the polishing area during polishing, thereby improving the polishing effect.

[0011] As an optimization, in the aforementioned hemispherical resonator expansion polishing method based on rheological principle, the deflection device is a rotary table; a short guide rail is fixed on the rotary table; the tool spindle is arranged on the short guide rail; in step two, the position of the workpiece spindle and the tool spindle is adjusted by a tool setting system; the tool setting system comprises a CCD camera, an X-direction slider and a Y-direction slider; the X-direction slider is slidingly arranged on an X-direction guide rail, and the Y-direction slider is slidingly arranged on a Y-direction guide rail; the workpiece spindle is fixed on the X-direction slider, and the rotary table is fixed on the Y-direction slider; during adjustment, the CCD camera acquires images of each part and transmits the images to an external computer; the X-direction slider is slid until the axis of the workpiece spindle coincides with the axis of the tool spindle (i.e. X-direction tool setting); then the tool spindle is slid so that the spherical center of the polishing tool is located on the rotation axis of the rotary table; and then the Y-direction slider is slid until the spherical center of the polishing tool coincides with the spherical center of the hemispherical resonator (i.e. Y-direction tool setting). The tool setting system has the above structure, and is convenient to assemble and implement; in addition, the tool setting in X-direction and Y-direction is realized by sliding the X-direction slider and the Y-direction slider, and the operation is very convenient. Further, a microscopic magnifying lens is arranged on the CCD camera. Thus, the image received by the external computer is an image magnified by the microscopic magnifying lens, which is convenient for the operator to observe and makes the tool setting result more accurate.

[0012] As an optimization, in the aforementioned hemispherical resonator expansion polishing method based on rheological principle, the end of the inner lip of the polishing tool is in the form of a circular arc and matches the inner root transition circular arc of the hemispherical resonator, and the end of the outer lip of the polishing tool is in the form of a circular arc and matches the outer root transition circular arc of the hemispherical resonator; along the axis direction of the polishing tool, the inner lip is lower than the outer lip by Δh, R2 is the inner spherical surface radius of the hemispherical resonator. Thus, the lip of the polishing tool can better cooperate with the root transition circular arc of the hemispherical resonator, and the polishing effect is further improved.

[0013] As an optimization, in the aforementioned hemispherical resonator expansion polishing method based on rheological principle, different polishing liquids can be used based on different rheological effects.

[0014] When polishing by using force rheological effect: the lip is made of metal, nylon or composite material; the polishing liquid used is a non-Newtonian fluid polishing liquid with shear thickening effect, and the abrasive is selected from one or more of diamond, alumina, silica sol and cerium oxide, with a mass fraction of 5% to 20%. In the process of relative shearing motion between the non-Newtonian fluid polishing liquid and the surface of the hemispherical resonator, shear rheological effect occurs, thereby enhancing the holding force of the abrasive in the polishing liquid, and especially the polishing liquid between the lip and the workpiece, the shear rheological effect makes it form a semi-annular flexible abrasive tool; during polishing, the polishing of the surface of the hemispherical resonator is realized by holding the free abrasive, which can effectively avoid scratching the surface of the hemispherical resonator by large particles.

[0015] When using the magnetic rheological effect polishing: the lip is made of permanent magnetic material; the polishing liquid used is magnetic rheological polishing liquid, which is a suspension formed by uniformly mixing magnetic particles, abrasive, base fluid (water-based or oil-based), and stabilizer. When the magnetic rheological polishing liquid is close to the narrow gap between the hemispherical resonator and the front end lip of the polishing tool, it will harden under the action of a high gradient magnetic field and generate shear force in the contact area to remove the material on the surface of the hemispherical resonator.

[0016] As an optimization, in the aforementioned hemispherical resonator generating polishing method based on the rheological principle, the connecting rod, the inner support web, and the outer support web can be integrally formed by 3D printing. At this time, the structure is simple and easy to manufacture. Alternatively, the connecting rod, the inner support web, and the outer support web can be separately manufactured and then combined together. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a step flow chart of the hemispherical resonator generating polishing method based on the rheological principle of the present application;

[0018] Figure 2 is a structural schematic diagram of the polishing device in Example 1 of the present application;

[0019] Figure 3 is an enlarged schematic diagram of part A in Figure 2

[0020] Figure 4 is a structural schematic diagram of the polishing container in Example 1 of the present application;

[0021] Figure 5 is a schematic diagram of the polishing device in Figure 2 after the polishing container is assembled;

[0022] Figure 6 is a matching state diagram of the polishing tool and the hemispherical resonator during polishing;

[0023] Figure 7 is a structural schematic diagram of the polishing tool in Example 2 of the present application;

[0024] Figure 8 is a structural schematic diagram of the polishing device in Example 4 of the present application;

[0025] Figure 9 is a schematic diagram of the cradle structure in Figure 8

[0026] Figure 10 is a structural schematic diagram of the polishing container in Example 4 of the present application;

[0027] Figure 11 is a structural schematic diagram of the polishing device in Example 5 of the present application;

[0028] ​​Figure 12 is a structural schematic diagram of a polishing container in Embodiment 5 of the present application;

[0029] Figure 13 is a state diagram of the polishing tool cooperating with the hemispherical resonator in steps two and three of the present application;

[0030] Figure 14 is a schematic diagram of the polishing liquid in the hemispherical resonator forming an approximate ring line on the inner / outer spherical surface when the polishing tool rotates;

[0031] Figure 15 is a principle diagram for determining the β angle in the present application;

[0032] Figure 16 is a space curve diagram of the polishing liquid on the inner spherical surface when the polishing tool rotates;

[0033] Figure 17 is an envelope diagram of the inner / outer spherical surface of the hemispherical resonator during polishing.

[0034] The marks in the drawings are as follows: 1-workpiece spindle; 2-tool spindle; 3-polishing tool, 31-connecting rod, 32-inner support web, 321-inner arc plate, 33-outer support web, 331-outer arc plate, 34-lip; 4-rotary table; 5-CCD camera; 6-X direction slide; 7-X direction guide rail; 8-Y direction slide; 9-Y direction guide rail; 10-short guide rail; 11-fixed frame; 12-swing frame; 13-cradle base; 14-robot arm; 15-base; 16-hemispherical resonator; 17-Z direction slide; 18-polishing container, 181-A plate, 182-B plate, 183-C plate, 1801-receiving groove, 184-housing, 185-D plate. DETAILED DESCRIPTION

[0035] The present application will be further described below in conjunction with the drawings and embodiments, but is not limited to the basis of the present application.

[0036] In order to overcome the problems of low efficiency, low precision and poor surface quality of the hemispherical resonator polishing method in the prior art, the present application provides a hemispherical resonator generating polishing method based on rheological principle, which has the advantages of high efficiency, high quality and high precision; the method uses a hemispherical resonator generating polishing device to polish the hemispherical resonator.

[0037] The hemispherical resonator expansion polishing device comprises a workpiece spindle 1, a tool spindle 2, a polishing tool 3, a deflection device and a tool setting system; the workpiece spindle 1 is used for clamping a hemispherical resonator 16 to be polished and driving the hemispherical resonator 16 to rotate; the tool spindle 2 is used for clamping the polishing tool 3 and driving the polishing tool 3 to rotate; the polishing tool 3 comprises a connecting rod 31, the connecting rod 31 is provided with an inner support web 32 and an outer support web 33, the end portions of the inner support web 32 and the outer support web 33 are provided with lips 34 for polishing; the tool spindle 2 is arranged on the deflection device; the deflection device is used for driving the tool spindle 2 to deflect by a certain angle, so that the axis of the polishing tool 3 and the axis of the hemispherical resonator 16 form a certain angle; the tool setting system is used for adjusting the positions of the workpiece spindle 1 and the tool spindle 2.

[0038] Embodiment 1

[0039] Referring to Figure 2 and Figure 3 , the deflection device in the embodiment is a rotary table 4; the rotary table 4 is fixed with a short guide rail 10, and the tool spindle 2 is slidingly arranged on the short guide rail 10; the tool setting system comprises a CCD camera 5, an X-direction sliding block 6 and a Y-direction sliding block 8; the X-direction sliding block 6 is slidingly arranged on an X-direction guide rail 7, and the Y-direction sliding block 8 is slidingly arranged on a Y-direction guide rail 9; the workpiece spindle 1 is fixed on the X-direction sliding block 6 through a support, and the rotary table 4 is fixed on the Y-direction sliding block 8; the CCD camera 5 is arranged on the top of the support through a fixing frame 11; the CCD camera 5 is provided with a microscopic magnifying lens, and the CCD camera 5 is located above the workpiece spindle 1.

[0040] The end portions of the inner lip and the outer lip of the polishing tool 3 are in the shape of a circular arc, and respectively match the inner root transition circular arc and the outer root transition circular arc of the hemispherical resonator 16; along the axis direction of the polishing tool 3, the inner lip is lower than the outer lip by Δh, R1 is the outer spherical surface radius of the hemispherical resonator, R2 is the inner spherical surface radius of the hemispherical resonator 16, r is the inner and outer root transition circular arc radius of the hemispherical resonator 16, D is the center rod diameter of the hemispherical resonator, and β is the included angle between the axis of the polishing tool 3 and the axis of the hemispherical resonator 16 during polishing.

[0041] The connecting rod 31, the inner support web 32 and the outer support web 33 are integrally formed by 3D printing; the outer support web 33 is in the shape of a hemisphere, and the inner support web 32 is in the shape of a cone and is hollow in the middle (see Figure 6 ). The polishing container 18 comprises an A plate 181, a B plate 182 and three C plates 183; the A plate 181 and the B plate 182 are respectively provided with through holes for the hemispherical resonator 16 and the polishing tool 3 to pass through (see Figure 4A, B, C plate are transparent acrylic plate.

[0042] Referring to Figure 1 , based on the rheological principle of hemispherical harmonic oscillator expansion polishing method,

[0043] comprising the following steps:

[0044] Step one, the hemispherical harmonic oscillator 16 from the hole in the A plate 181 (the outer anchor rod 161 is provided with two rubber ring, distribution in the inside and outside of A plate 181, to realize the sealing), and installed on the workpiece spindle 1 (workpiece spindle 1 on the ER chuck will be the outer anchor rod 161 of the hemispherical harmonic oscillator), coaxial with the workpiece spindle 1, adjust its radial runout error is less than 10 μm; the polishing tool 3 from the hole in the B plate 182 (connecting rod 31 is provided with two rubber ring, distribution in the inside and outside of B plate 182, to realize the sealing), and installed on the tool spindle 2, coaxial with the tool spindle 2, adjust its radial runout error is less than 10 μm, to ensure the position accuracy of the hemispherical harmonic oscillator 16 and polishing tool 3 after installation.

[0045] Step two, CCD camera 5 to obtain the image of each part (workpiece spindle 1, tool spindle 2, polishing tool 3, rotary table 4, hemispherical harmonic oscillator 16) and transmitted to the external computer, in the computer to establish the coordinate system, and mark the axis of the workpiece spindle 1 and workpiece spindle 2, rotary table 4 rotation axis, and the ball center of polishing tool 3 and hemispherical harmonic oscillator 16; sliding X direction slider 6, until the axis of the workpiece spindle 1 and the axis of the tool spindle 2 coincide; then slide the tool spindle 2, so that the ball center of the polishing tool 3 is located on the rotation axis of the rotary table 4, and then slide the Y direction slider 8, so that the ball center of the polishing tool 3 coincides with the ball center of the hemispherical harmonic oscillator 16 (see Figure 13 a).

[0046] Step three, start the rotary table 4, drive the tool spindle 2 to deflect, so that the angle between the axis of the polishing tool 3 and the axis of the hemispherical harmonic oscillator 16 is β (see Figure 13 b), form polishing assembly; at this time, the minimum gap between the outer root transition arc of the hemispherical harmonic oscillator 16 and the outer lip along is d1, and the minimum gap between the inner root transition arc and the inner lip along is d2; then A plate 181, B plate 182, C plate 183 connected combination into a hollow hexahedron box (see Figure 5 , each plate is connected by buckling, and the connection position is sealed by sealing element). The gap of d1, d2 is used to produce shear thickening (the flexible abrasive tool formed between the lip along 34 and the workpiece spherical surface is semicircular, with the rotation of the workpiece, the whole hemispherical surface can be polished, similar to the gear machining by expansion method); if the distance is too small, the polishing liquid cannot flow through, if the distance is too large, the material removal rate is low; according to many experiments, the value range can be 1 mm ± 0.25 mm.

[0047] Referring to Figure 15 , the circle part represents the inner and outer lip edge part of the polishing tool 3 (the cross-sectional radius of the outer lip edge is r-d1, the mean diameter is R1+r; the cross-sectional radius of the inner lip edge is r-d2, the mean diameter is R2-r), which is consistent with the inner and outer root transition arc of the hemispherical resonator 16, and the blank part between them is the polishing gap. Since the axis of the polishing tool 3 is perpendicular to the plane where the lip edge 34 is located, the angle between the plane where the outer lip edge of the polishing tool 3 is located and the axis of the hemispherical resonator 16 is Therefore

[0048] Step four, add the polishing liquid into the polishing container 18 to form a polishing liquid station, and immerse the polishing assembly completely in the polishing liquid; at the same time, start the workpiece spindle 1 to drive the hemispherical resonator 16 to rotate at a speed of 240 rpm (according to the different characteristics of the polishing liquid, the speed can be 10-300 rpm), and start the tool spindle 2 to drive the polishing tool 3 to rotate at a speed of 1000 rpm (according to the different characteristics of the polishing liquid, the speed can be 100-3000 rpm); at this time, the polishing tool 3 and the hemispherical resonator 16 rotate relatively, and the polishing liquid forms two developing polishing flow fields in the gap between the inner support web 32 and the inner spherical surface of the hemispherical resonator 16 and the gap between the outer support web 33 and the outer spherical surface of the hemispherical resonator 16, thereby polishing the inner spherical surface, the outer spherical surface and the root transition arc of the hemispherical resonator 16.

[0049] Step five, when the set polishing time T is reached, the hemispherical resonator is cleaned and taken out, and the polishing is completed. Among them, the workpiece spindle 1, the tool spindle 2 and the turntable 4 can be driven to rotate by a motor.

[0050] In this embodiment, the polishing method is based on the force flow principle, the lip edge 33 is a toothed ring structure and is made of metal; the polishing liquid used is a non-Newtonian fluid polishing liquid with shear thickening effect, which is configured by using a polyhydroxy polymer (PHHP) and water as a base liquid (the mass fraction of the polyhydroxy polymer is 50%), and adding 3000# aluminum oxide abrasive and xanthan gum additive to obtain (in the polishing liquid, the mass fraction of the abrasive is 10%).

[0051] The hemispherical resonator with R2 of 15 mm, R1 of 16 mm, D of 6 mm and r of 2 mm is polished by using the above-mentioned polishing method; during polishing, β is 71 degrees, d1 and d2 are 1 mm, and the polishing time is 1 hour. The surface roughness of the polished hemispherical resonator is measured, and the roughness has obviously decreased, and the average roughness Ra of the inner and outer root transition arcs and the inner and outer spherical surfaces is less than 5 nm, as shown in the following table,

[0052]

[0053] Example 2:

[0054] Referring to Figure 7 Different from example 1, in this embodiment, the inner support web 32 comprises two symmetrically distributed inner arc-shaped plates 321; the outer support web 33 comprises two symmetrically distributed outer arc-shaped plates 331, the inner arc-shaped plates 321 and the outer arc-shaped plates 331 are 90°; at this time, it is convenient for the polishing liquid to flow into the polishing area during polishing, improving the polishing effect, and also avoiding a large amount of polishing liquid being thrown off when the rotation speed of the tool spindle and the workpiece spindle is too fast.

[0055] Example 3:

[0056] In this embodiment, the polishing method is based on the magneto-rheological principle, the lip 33 is a magnetic toothed ring (which can be realized by inlaying permanent magnets); the polishing liquid used is a magneto-rheological polishing liquid with magneto-rheological effect, which adopts discrete micron-level magnetic particles, carrier liquid and surfactant as base liquid, and then adds 3000# alumina abrasive and xanthan gum additive to the base liquid to obtain (in the polishing liquid, the mass fraction of the abrasive is 10%). The remaining polishing steps are the same as those of example 1.

[0057] Example 4:

[0058] Referring to Figure 8 and Figure 9 Different from example 1, in this embodiment, the deflection device is a swing frame 12; the swing frame 12 is rotationally connected with the cradle base 13; the tool spindle 2 is slidably arranged on the Z-direction slide 17, the Z-direction slide 17 is slidably arranged on the X-direction guide rail 7; the workpiece spindle 1 is fixed on the swing frame 12, the cradle base 13 is slidably arranged on the Y-direction guide rail 9; the CCD camera 5 is fixed on the workbench by the fixing frame 11; the CCD camera 5 is provided with a microscopic magnifying lens and is located at the side of the workpiece spindle 1. The polishing container 18 is a hollow hexahedron box, the top of which is provided with a containing groove 1801, and the bottom of the containing groove 1801 is provided with a through hole (see Figure 10 ); it is made of transparent acrylic plate.

[0059] In the polishing method of the embodiment, in the step one, the polishing container 18 is installed on the swing frame 12, the hemispherical resonator 16 passes through the through hole on the polishing container 18 and is installed on the workpiece spindle 1; in the step two, the CCD camera 5 acquires the image of each part and transmits to the external computer; the slide swing basket base 13 is slid until the axis of the workpiece spindle 1 coincides with the axis of the tool spindle 2; then the Z direction slide 17 is slid to make the ball center of the polishing tool 3 coincide with the ball center of the hemispherical resonator, and the coincidence point is located on the rotation axis of the swing frame 12; in the step three, the swing frame 12 is controlled to rotate to make the included angle between the axis of the polishing tool 3 and the axis of the hemispherical resonator 16 be β (at this time, the hemispherical resonator 16 and the polishing tool 3 are located in the containing groove 1801). The steps one, four and five are the same as those in the embodiment 1.

[0060] Embodiment 5

[0061] Referring to Figure 11 , different from the embodiment 1, in the embodiment, the tool setting system comprises the CCD camera 5 and the mechanical arm 14 (the included angle between the axis of the polishing tool 3 and the axis of the hemispherical resonator 16 is adjusted by the mechanical arm 14; therefore, the deflection device is not needed to be additionally arranged); the workpiece spindle 1 is fixed on the workbench by the base 15; the tool spindle 2 is arranged at the end of the mechanical arm 14; the CCD camera 5 is fixed on the workbench by the fixing frame 11; the CCD camera 5 is provided with a microscopic magnifying lens and is located at the side of the workpiece spindle 1. The polishing tool 18 comprises a shell 184 and a D plate 185; the D plate 185 is provided with a through hole for the polishing tool 3 to pass through; the shell 184 is surrounded by four plates, and one of the plates is provided with a through hole for the hemispherical resonator 16 to pass through (see Figure 12 ).

[0062] In the polishing method of the embodiment, in the step one, the polishing container 18 is installed on the base 15, the hemispherical resonator 16 passes through the through hole on the shell 184 and is installed on the workpiece spindle 1; the polishing tool 3 passes through the through hole on the D plate 185 and is fixed on the tool spindle 2; in the step two, the CCD camera 5 acquires the image of each part and transmits to the external computer; the spatial position of the end of the mechanical arm 14 is adjusted to make the axis of the hemispherical resonator 16 coincide with the axis of the polishing tool 3, and a safety position is set, then the ball center of the polishing tool 3 is made to coincide with the ball center of the hemispherical resonator 16 by moving the mechanical arm 14, and the initial machining position is set; in the step three, the mechanical arm 14 is controlled to rotate to make the included angle between the axis of the polishing tool 3 and the axis of the hemispherical resonator 16 be β; the shell 184 and the D plate 185 are connected and combined into a hollow hexahedron box with an open top, and the connection position is sealed by a sealing member. The steps one, four and five are the same as those in the embodiment 1.

[0063] The polishing principle of the present application is:

[0064] Referring to Figure 14 , the axis of the polishing tool 3 intersects with the axis of the hemispherical resonator 16 at point o, the angle between the two axes is β, and the polishing tool 3 and the hemispherical resonator 16 rotate around their own axes respectively; the axis of the hemispherical resonator 16 is the Z axis, and the inner and outer spherical surface radii are R2 and R1 respectively. The polishing tool 3 and the inner and outer spherical surface of the hemispherical resonator 16 are not in contact with a machining gap therebetween, and the polishing liquid can form an approximately annular line on the inner and outer spherical surface of the hemispherical resonator 16 through the rotation of the polishing tool 3 around its own axis, which can be simplified as a circle parallel to the X axis.

[0065] When polishing the inner spherical surface, the center of the circle is (0, R1 / 2, tanθ*R1 / 2), the radius is R, the angle between the radius and the YOZ plane is θ, and the annular line is a spatial curve (see Figure 16 ) when looking at point o along the axis of the polishing tool in the counterclockwise direction. Then:

[0066] f(θ)=-R sinθ

[0067]

[0068]

[0069] 0<θ<2π;

[0070] The hemispherical resonator 16 rotates around its axis, and according to the relativity of motion, it is equivalent to that the hemispherical resonator 16 is stationary and the polishing tool 3 rotates around the axis of the hemispherical resonator 16 for one revolution, i.e. rotates around the Z axis for one revolution. Then:

[0071]

[0072]

[0073]

[0074]

[0075] 0<θ<2π;

[0076] v0 is the rotation speed of the hemispherical resonator, and t is an arbitrary time during polishing.

[0077] During polishing, the inner and outer spherical surface and the root transition arc of the hemispherical resonator are polished by using the magneto-rheological characteristics or shear rheological characteristics of the polishing liquid. The inner surface of the hemispherical resonator is a hemisphere with a radius of R2, and the outer surface is a hemisphere with a radius of R1. The envelope diagram of the inner and outer spherical surface of the hemispherical resonator during polishing is shown in Figure 17 .

[0078] It should be noted that the present application is by means of constructing a polishing liquid station, so that the polishing tool 3 and the hemispherical resonator 16 are completely immersed in the polishing liquid, and the polishing processing of the hemispherical resonator is realized; of course, other ways can also be used to provide the polishing liquid.

[0079] The general description of the invention involved in the present application and the description of the specific embodiments should not be understood as a limitation on the technical solutions of the invention. Based on the disclosure of the present application, those skilled in the art can add, reduce or combine the disclosed technical features in the general description or / and the specific embodiments (including examples) without violating the elements of the invention involved, to form other technical solutions within the protection scope of the present application.

Claims

1. A hemispherical resonator developing and polishing method based on rheological principles, characterized by: The polishing method uses a hemispherical resonator expansion polishing device to polish a hemispherical resonator; the hemispherical resonator expansion polishing device comprises a workpiece spindle (1), a tool spindle (2), a polishing tool (3) and a deflection device; the workpiece spindle (1) is used to clamp the hemispherical resonator (16) to be polished and drive the hemispherical resonator (16) to rotate; the tool spindle (2) is used to clamp the polishing tool (3) and drive the polishing tool (3) to rotate; the polishing tool (3) comprises a connecting rod (31), the connecting rod (31) is provided with an inner supporting spoke (32) and an outer supporting spoke (33), and the ends of the inner supporting spoke (32) and the outer supporting spoke (33) are both provided with a lip edge (34); the tool spindle (2) is provided on the deflection device; the deflection device is used to drive the tool spindle (2) to deflect a certain angle, so that the axis of the polishing tool (3) and the axis of the hemispherical resonator (16) form a certain angle; The polishing method comprises the following steps: Step 1: Install the hemispherical resonator (16) on the workpiece spindle (1) and make it coaxial with the workpiece spindle (1); install the polishing tool (3) on the tool spindle (2) and make it coaxial with the tool spindle (2); Step 2: Adjust the positions of the workpiece spindle (1) and the tool spindle (2) so that the axis of the workpiece spindle (1) coincides with the axis of the tool spindle (2), and the center of the polishing tool (3) coincides with the center of the hemispherical resonator (16), and the coincidence point is located on the rotation axis of the deflection device; Step 3: Start the deflection device to drive the tool spindle (2) to deflect, so that the angle between the axis of the polishing tool (3) and the axis of the hemispherical resonator (16) is β, forming a polishing assembly; R1 is the outer spherical radius of the hemispherical resonator (16), D is the central rod diameter of the hemispherical resonator (16), and r is the root transition arc radius of the hemispherical resonator (16); at this time, the minimum gap between the outer root transition arc and the outer lip edge of the hemispherical resonator (16) is d1, and the minimum gap between the inner root transition arc and the inner lip edge is d2; Step 4: construct a polishing liquid station, immerse the polishing assembly in the polishing liquid, and at the same time, start the workpiece spindle (1) to drive the hemispherical resonator (16) to rotate, and start the tool spindle (2) to drive the polishing tool (3) to rotate; at this time, the polishing tool (3) and the hemispherical resonator (16) rotate relative to each other, and the polishing liquid forms two polishing flow fields in the gap between the inner supporting spoke (32) and the inner sphere of the hemispherical resonator (16) and the gap between the outer supporting spoke (33) and the outer sphere of the hemispherical resonator (16), thereby polishing the inner sphere, outer sphere and root transition arc of the hemispherical resonator (16); Step 5: When the set polishing time T is reached, the hemispherical resonator (16) is cleaned and taken out, and the polishing is completed.

2. The hemispherical resonator developing and polishing method based on rheological principle according to claim 1, characterized in that: The lip edge (34) is a toothed structure.

3. The hemispherical resonator developing and polishing method based on rheological principle according to claim 2, characterized in that: The inner supporting spoke (32) includes a group of inner arc-shaped plates (321) distributed at intervals along the circumferential direction; the outer supporting spoke (33) includes a group of outer arc-shaped plates (331) distributed at intervals along the circumferential direction.

4. The hemispherical resonator developing and polishing method based on rheological principle according to claim 2, characterized in that: The inner supporting radian plate (32) and the outer supporting radian plate (33) are conical, cylindrical or hemispherical, and their surfaces are hollow.

5. The hemispherical resonator developing and polishing method based on rheological principle according to claim 3 or 4, characterized in that: The deflection device is a turntable (4); a short guide rail (10) is fixed on the turntable (4), and the tool spindle (2) is arranged on the short guide rail (10); in the second step, the positions of the workpiece spindle (1) and the tool spindle (2) are adjusted by a tool setting system; the tool setting system includes a CCD camera (5), an X-direction slider (6) and a Y-direction slider (8); the X-direction slider (6) is slidably arranged on the X-direction guide rail (7), and the Y-direction slider (8) is slidably arranged on the Y-direction guide rail (9); the workpiece spindle (1) is fixed on the X-direction slider (6), and the turntable (4) is fixed on the Y-direction slider (8); during adjustment, the CCD camera (5) obtains images of each part and transmits them to an external computer, and the X-direction slider (6) is slid until the axis of the workpiece spindle (1) coincides with the axis of the tool spindle (2); Then, the tool spindle (2) is slid to position the center of the polishing tool (3) on the rotation axis of the turntable (4), and then the Y-direction slider (8) is slid until the center of the polishing tool (3) coincides with the center of the hemispherical resonator (16).

6. The hemispherical resonator developing and polishing method based on rheological principle according to claim 5, characterized in that: The CCD camera (5) is provided with a microscope magnifying lens.

7. The hemispherical resonator developing and polishing method based on rheological principle according to claim 5, characterized in that: The ends of the inner lip and the outer lip of the polishing tool (3) are in arc shape and respectively coincide with the inner root transition arc and the outer root transition arc of the hemispherical resonator (16); along the axial direction of the polishing tool (3), the inner lip is lower than the outer lip by Δh, R2 is the inner spherical radius of the hemispherical resonator (16).

8. The hemispherical resonator developing and polishing method based on rheological principle according to claim 7, characterized in that: The lip edge (34) is made of metal, nylon or composite material; the polishing liquid is a non-Newtonian fluid polishing liquid with a shear thickening effect, and the abrasive is a mixture of one or more of diamond, aluminum oxide, silica sol and cerium oxide, with a mass fraction of 5% to 20%, thereby realizing force rheological polishing.

9. The hemispherical resonator developing and polishing method based on rheological principle according to claim 7, characterized in that: The lip edge (34) is made of permanent magnetic material; the polishing liquid is a magnetorheological polishing liquid, which is a suspension formed by uniformly mixing magnetic particles, abrasives, base liquid and stabilizer, thereby realizing magnetorheological polishing.

10. The hemispherical resonator developing and polishing method based on rheological principle according to claim 3 or 4, characterized in that: The connecting rod (31), the inner supporting spoke (32) and the outer supporting spoke (33) are integrally formed by 3D printing.

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