Ultra-precise small-caliber optical grinding machine integrated with polishing function and machining process of ultra-precise small-caliber optical grinding machine

Abstract

The invention relates to the field of ultra-precision optical grinding machines, and provides an ultra-precision small-caliber optical grinding machine integrated with a polishing function and a machining process of the ultra-precision small-caliber optical grinding machine. The small-caliber optical grinding machine achieves micron-order feeding and single-point grinding through multi-axis cooperative movement, meanwhile, due to the position distribution of a machine tool grinding wheel shaft, the high-speed grinding main shaft and the B-axis hydrostatic pressure rotary table, the torque of the B-axis hydrostatic pressure rotary table can meet the cutting torque formed by grinding force more easily, the precision stability of the machined surface type of an optical part is improved, and the machining precision of the optical part is improved. The problems that strong interference geometric components and thin-wall fragile parts are fragile in the rough grinding process and the polishing process is low in efficiency are solved. The workpiece static pressure main shaft clamps the bar through the clamp with the cavity inside, the workpiece can be cut off after machining, part of the remaining length of the bar in the clamp is pulled out to machine the next workpiece, the problem that a current ultra-precision machine tool cannot achieve small-batch machining through one-time clamping of the optical element bar is solved, and the machining precision and the machining efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of ultra-precision optical grinding machine, and particularly relates to an ultra-precision small-bore optical grinding machine integrated with polishing function and a machining process thereof. BACKGROUND

[0002] In the field of ultra-precision machining of brittle materials and complex parts with strong geometric interference, the current production mainly relies on imported general five-axis machining centers. However, when facing the harsh machining task of high-precision optical elements, the inherent limitations of such general equipment become increasingly prominent. First, the motion control precision and system rigidity are often difficult to meet the machining tolerance of microns or even nanometers, resulting in that the machining precision and surface quality of the final product cannot meet the ideal standard. Second, when machining hard and brittle materials such as quartz glass, the traditional machining method is easy to introduce micro-cracks and other subsurface damage under the surface layer of the part, which will seriously affect the optical performance and long-term reliability of the element. In addition, the machining efficiency of the equipment is low, which is difficult to meet the production mode of small batch and high efficiency, thereby restricting the development of related high-end manufacturing fields. SUMMARY

[0003] The present application provides an ultra-precision small-bore optical grinding machine integrated with polishing function to solve the problems of low machining efficiency and easy breakage of workpieces in the prior art.

[0004] The present application provides an ultra-precision small-bore optical grinding machine integrated with polishing function, comprising: a machine tool main body; a main support frame assembly, the machine tool main body is arranged on the upper part of the main support frame assembly; the main support frame assembly comprises a main support frame body and a plurality of air passive vibration isolators, a plurality of air passive vibration isolators are vertically and spaced arranged on the upper part of the main support frame body, and the upper ends of the plurality of air passive vibration isolators are connected with the machine tool main body; an X-axis hydrostatic guide rail static pressure unit, the X-axis hydrostatic guide rail static pressure unit is arranged on the upper part of the machine tool main body along the X-axis; a Z-axis hydrostatic guide rail static pressure unit, the Z-axis hydrostatic guide rail static pressure unit is arranged on the upper part of the machine tool main body along the Z-axis; a B-axis hydrostatic rotary table, the B-axis hydrostatic rotary table is arranged on the upper part of the Z-axis hydrostatic guide rail static pressure unit, the upper part of the B-axis hydrostatic rotary table is provided with a high-speed grinding spindle, the B-axis hydrostatic rotary table is used for driving the high-speed grinding spindle to rotate around the B-axis, and the high-speed grinding spindle is used for mounting a grinding wheel and driving the grinding wheel to rotate around the C-axis; X, Z shafts keep the oil temperature in the internal oil return groove stable, ensure the stability of the precision of the hydrostatic guide rail system and the repeat positioning precision of the X, Z shafts, and ensure the consistency of the machining size and surface type precision; the B shaft hydrostatic rotary table and the X, Z shafts adopt the design of the same kinematic viscosity and the same pressure of the hydraulic oil, and the stability of the B shaft center height and the rotary center coordinate is ensured through the oil temperature; A vertical driving unit is arranged at the upper portion of the X shaft hydrostatic guide rail static pressure unit. A workpiece hydrostatic spindle is arranged at one side of the vertical driving unit and above the B shaft hydrostatic rotary table; the workpiece hydrostatic spindle is provided with a clamp, the inside of the clamp is hollow, and the clamp is used for realizing manual extraction of a bar, clamping the bar and realizing machining of multiple workpieces from one bar; the vertical driving unit is used for driving the workpiece hydrostatic spindle to move along the Y shaft; an acoustic emission sensor is arranged on the workpiece hydrostatic spindle, and the acoustic emission sensor is used for detecting the AE signal of a grinding wheel and realizing quick tool setting and anti-collision of the machine tool through the acoustic emission sensor.

[0005] The ultra-precision small-bore optical grinding machine with integrated polishing function further comprises: An electric control cabinet; An external support is arranged around the outer periphery of the main support frame assembly, an upper portion of the external support is provided with an opening, the machine tool body extends out of the opening, and the electric control cabinet is arranged at the upper portion of the external support.

[0006] The ultra-precision small-bore optical grinding machine with integrated polishing function further comprises:

[0007] The ultra-precision small-bore optical grinding machine with integrated polishing function further comprises:

[0008] The ultra-precision small-bore optical grinding machine with integrated polishing function further comprises:

[0009] The ultra-precision small-bore optical grinding machine with integrated polishing function further comprises:

[0010] The application further provides a machining process of the ultra-precision small-bore optical grinding machine integrated with a polishing function. Coarse grinding forming, firstly, the outer suspension column of the inner sphere is roughened by a disc grinding wheel, and then the excess material outside the outer circle reference is removed by the disc grinding wheel; then, the inner spherical surface is roughened by a coarse grinding inner profile grinding wheel, in this process, the B-axis liquid static pressure turntable needs to be rotated to a fixed angle, so as to drive the grinding wheel rotating shaft to form a fixed included angle with the workpiece shaft, wherein the fixed included angle is determined by the workpiece size; during the coarse grinding of the inner spherical surface, the X-axis and Y-axis positions are fixed, and only the Z-axis needs to be fed; after the coarse grinding of the inner spherical surface is completed, the outer suspension column of the outer sphere is roughened by the disc grinding wheel; then the B-axis liquid static pressure turntable is rotated to make the included angle between the grinding wheel shaft and the workpiece shaft be 90°, after the Z-axis feeding drives the coarse grinding outer profile grinding wheel to reach a determined position, the roughening of the outer spherical surface can be realized only by the X-axis feeding, and thus the hemispherical resonator workpiece is initially formed; Semi-fine grinding, the inner spherical surface and the inner spherical column are semi-finely ground by a semi-fine grinding inner profile grinding wheel; the outer spherical surface is semi-finely ground by a semi-fine grinding outer profile grinding wheel, and the rotation angles of the B-axis liquid static pressure turntable during the semi-fine grinding of the inner and outer spherical surfaces are the same as those during the coarse grinding of the inner and outer spherical surfaces; and then the outer spherical column is semi-finely ground by the disc grinding wheel; Fine grinding, the inner spherical surface and the inner spherical column are finely ground by a fine grinding inner profile grinding wheel, and the outer spherical surface is finely ground by a fine grinding outer profile grinding wheel, and the rotation angles of the B-axis liquid static pressure turntable during the fine grinding of the inner and outer spherical surfaces are the same as those during the coarse grinding of the inner and outer spherical surfaces; and then the outer spherical column is finely ground by the disc grinding wheel; During the above machining processes, the grinding shaft and the workpiece rotate around their own shafts, respectively; Cutting, the outer spherical column is cut off by a cutting grinding wheel to obtain a finished product; The rod is extracted to a predetermined length by opening the clamp, and then the rod is clamped again by the clamp; The above steps are repeated in sequence until the rod is machined.

[0011] According to the machining process of the ultra-precision small-bore optical grinding machine integrated with a polishing function, in the steps of the semi-fine grinding and the fine grinding, the end faces of the inner profile grinding wheel and the outer profile grinding wheel are obliquely cut at a fixed angle α, and the axis of the inner profile grinding wheel or the outer profile grinding wheel intersects with the axis of the workpiece at the workpiece sphere center.

[0012] The application provides an integrated polishing function ultra-precision small-bore optical grinding machine, micron-level feeding and single-point grinding are realized through multi-axis cooperative movement, meanwhile, the position distribution of the machine tool grinding wheel shaft, the grinding shaft and the rotary table shaft makes the torque of the B-axis liquid static pressure rotary table more easily meet the cutting torque formed by the grinding force, the surface type precision stability of the optical part is improved, the problems of breakage in the rough grinding process and low efficiency in the polishing process of strong interference geometric components and thin-walled fragile parts are solved. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0014] Figure 1 Fig. 1 is one of the schematic diagrams of the three-dimensional structure of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0015] Figure 2 Fig. 2 is the second schematic diagram of the three-dimensional structure of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0016] Figure 3 Fig. 3 is the third schematic diagram of the three-dimensional structure of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0017] Figure 4 Fig. 4 is the schematic diagram of the top view structure of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0018] Figure 5 Fig. 5 is the schematic diagram of the top view structure of the machine tool main body provided by the application.

[0019] Figure 6 Fig. 6 is one of the schematic diagrams of the machining process of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0020] Figure 7 Fig. 7 is one of the schematic diagrams of the machining process of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0021] Figure 8 Fig. 8 is one of the schematic diagrams of the machining process of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0022] Figure 9 is one of the processing processes of the integrated polishing function ultra-precision small-bore optical grinding machine provided by the application.

[0023] Reference signs: 10, machine tool main body; 11, backwater hole; 12, oil return groove; 20, X-axis hydrostatic guide rail static pressure unit; 30, Z-axis hydrostatic guide rail static pressure unit; 40, B-axis hydrostatic rotary table; 41, grinding fine adjustment mechanism; 50, high-speed grinding spindle; 60, vertical driving unit; 61, vertical Y-axis; 62, mounting frame; 70, workpiece static pressure spindle; 71, clamp; 80, external support; 81, control cabinet; 90, main support frame body; 91, air passive vibration isolator. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0025] In the description of the embodiments of the present application, it should be noted that the orientations or positional relationships indicated by the terms “center”, “longitudinal”, “transverse”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer” and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated thereby must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. In addition, the terms “first”, “second”, “third” are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0026] In the description of the embodiments of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms “connected” and “connected” should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0027] In the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature can be "above", "over" and "on" the second feature, which can be that the first feature is directly above or obliquely above the second feature, or only means that the first feature is higher in horizontal height than the second feature. The first feature can be "under", "below" and "underneath" the second feature, which can be that the first feature is directly below or obliquely below the second feature, or only means that the first feature is lower in horizontal height than the second feature.

[0028] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0029] As shown in Figure 1 and Figure 2 The ultra-precision small-bore optical grinding machine integrated with polishing function includes a machine tool main body 10, a main support frame assembly, an X-axis hydrostatic guide rail static pressure unit 20, a Z-axis hydrostatic guide rail static pressure unit 30, a B-axis hydrostatic rotary table 40, a vertical driving unit 60 and a workpiece hydrostatic spindle 70. The main support frame assembly includes a main support frame body 90 and a plurality of air passive vibration isolators 91, which are vertically and spaced apart on the upper part of the main support frame body 90, and the upper ends of the plurality of air passive vibration isolators 91 are connected with the machine tool main body 10.

[0030] The X-axis hydrostatic guide rail static pressure unit 20 is arranged on the upper part of the machine tool main body 10 along the X-axis; the Z-axis hydrostatic guide rail static pressure unit 30 is arranged on the upper part of the machine tool main body 10 along the Z-axis; both the X-axis hydrostatic guide rail static pressure unit 20 and the Z-axis hydrostatic guide rail static pressure unit 30 adopt hydrostatic guide rails, which can provide high-precision, high-rigidity and low-friction motion support, and ensure the stability and precision of the X-axis and Z-axis motion, thereby improving the overall machining precision.

[0031] The B-axis hydrostatic pressure rotary table 40 is arranged on the upper portion of the Z-axis hydrostatic pressure guide rail static pressure unit 30, the Z-axis hydrostatic pressure guide rail static pressure unit 30 is used to drive the B-axis hydrostatic pressure rotary table 40 to reciprocate along the Z-axis, the upper portion of the B-axis hydrostatic pressure rotary table 40 is provided with a high-speed grinding spindle 50, the B-axis hydrostatic pressure rotary table 40 is used to drive the high-speed grinding spindle 50 to rotate around the B-axis, and the high-speed grinding spindle 50 is used to install a grinding wheel and drive the grinding wheel to rotate around the C-axis. The B-axis hydrostatic pressure rotary table 40 can realize accurate angle positioning and rotation, and combined with the high-speed grinding spindle 50, the grinding machining of a complex curved surface and profile can be carried out.

[0032] The vertical driving unit 60 is arranged on the upper portion of the X-axis hydrostatic pressure guide rail static pressure unit 20, the X-axis hydrostatic pressure guide rail static pressure unit 20 is used to drive the vertical driving unit 60 to reciprocate along the Y-axis; the workpiece static pressure spindle 70 is arranged on one side of the vertical driving unit 60 and located above the B-axis hydrostatic pressure rotary table 40; the workpiece static pressure spindle 70 is provided with a clamp 71, the inside of the clamp 71 is hollow, used to realize manual extraction of a rod, the clamp 71 clamps the rod, realizing that one rod processes multiple workpieces; the vertical driving unit 60 is used to drive the workpiece static pressure spindle 70 to move along the Y-axis; the workpiece static pressure spindle 70 is provided with an acoustic emission sensor, the acoustic emission sensor is used to detect the AE signal of the grinding wheel, and the quick tool setting and anti-collision of the machine tool are realized through the acoustic emission sensor.

[0033] The integrated polishing function ultra-precision small-bore optical grinding machine provided by the application is a five-axis four-linkage ultra-precision numerical control small-bore optical grinding machine, has multiple machining capabilities such as rough grinding, fine grinding and polishing, the workpiece static pressure spindle 70, the high-speed grinding spindle 50, the B-axis hydrostatic pressure rotary table 40, the X-axis hydrostatic pressure guide rail static pressure unit 20 and the Z-axis hydrostatic pressure guide rail static pressure unit 30 all adopt direct drive technology combined with static pressure technology; micron-level feeding and single-point grinding are realized through multi-axis collaborative motion, meanwhile, the position distribution of the machine tool grinding wheel shaft, the high-speed grinding spindle 50 and the B-axis hydrostatic pressure rotary table 40 makes the torque of the B-axis hydrostatic pressure rotary table 40 more easily meet the cutting torque formed by the grinding force, improves the optical part machining surface type precision stability, and solves the problems of breakage in the rough grinding process and low efficiency in the polishing process of strong interference geometric components and thin-walled fragile parts. The workpiece static pressure spindle 70 clamps the rod through the clamp 71 with an internal cavity, after machining, the workpiece can be cut off and the rod with the remaining length in the clamp 71 is extracted to process the next workpiece, thus solving the problem that the current ultra-precision machine tool is difficult to realize small-batch processing through one-time clamping of an optical element rod, and improving the machining efficiency.

[0034] In an embodiment of the application, as Figure 1 and Figure 2As shown, the vertical driving unit 60 includes a mounting frame 62 and a vertical Y-axis 61, the mounting frame 62 is arranged on the upper part of the X-axis hydrostatic guide rail static pressure unit 20, the vertical Y-axis 61 is arranged on one side of the mounting frame 62, the vertical Y-axis 61 is arranged vertically, the slide plate of the vertical Y-axis 61 is connected with the workpiece static pressure main shaft 70, and the vertical Y-axis 61 is used for driving the workpiece static pressure main shaft 70 to move along the Y-axis. The vertical Y-axis 61 is arranged so that the workpiece static pressure main shaft 70 can be accurately moved in the Y-axis direction, accurate positioning and feeding of the workpiece are realized, and the needs of ultra-precision machining are met. The mounting frame 62 provides stable support for the vertical Y-axis 61, and ensures the rigidity and stability of the entire vertical driving unit 60.

[0035] In one embodiment of the present application, as shown in Figure 5 As shown, the upper part of the machine tool body 10 is provided with an oil return groove 12, and the X and Z axes pass through the internal oil return groove 12 to keep the oil temperature stable, ensure the stability of the precision of the guide rail static pressure system, and the repeat positioning accuracy of the X and Z axes, so as to ensure the consistency of the size and surface type precision of machining; the B-axis hydrostatic rotary table and the X and Z axes adopt the design of the same kinematic viscosity and the same pressure of the hydraulic oil, and the oil temperature is used to ensure the stability of the B-axis center height and the rotary center coordinates.

[0036] In one embodiment of the present application, as shown in Figure 3 As shown, the ultra-precision small-caliber optical grinding machine integrated with polishing function further comprises an electric control cabinet, a main support frame assembly and an external support 80, and the machine tool body 10 is arranged on the upper part of the main support frame assembly. The external support 80 is arranged around the outer periphery of the main support frame assembly, the upper part of the external support 80 is provided with an opening, the machine tool body 10 extends out of the opening, the main support frame assembly and the external support 80 form an inner-outer double support frame, and the machine tool body 10 is connected with the main support frame assembly. The electric control cabinet is arranged on the upper part of the external support 80, preferably, one side of the external support 80 is provided with a downwardly recessed recess, the electric control cabinet is arranged in the recess, and the electric control cabinet is connected with the external support 80 through bolts. Arranging the electric control cabinet in the recess can effectively utilize the space on one side of the external support 80, and can also reduce the installation height of the electric control cabinet, so that the overall gravity center of the small-caliber optical grinding machine is reduced, and the stability of the small-caliber optical grinding machine is improved. The main support frame assembly and the external support 80 are connected to form an integrated structure, which can realize overall hoisting of the whole machine, and improve the transportation efficiency.

[0037] In one embodiment of the present application, as shown in Figure 3As shown, four air passive isolators 91 are provided in the embodiment, of course, the number of air passive isolators 91 is not limited thereto, and is determined according to the shape of the main support frame body 90 and the weight of the machine tool body 10 and other factors. The main support frame body 90 is welded from a square tube, and the four air passive isolators 91 are vertically and spacedly arranged at the upper portion of the main support frame body 90, the lower ends of the four air passive isolators 91 are connected to the main support frame body 90 by bolts, and the upper ends of the four air passive isolators 91 are connected to the machine tool body 10 by bolts. The air passive isolators 91 provide a stable support platform for the machine tool body 10, and can effectively isolate external vibrations of 5 Hz and above, significantly reducing the influence of environmental low-frequency vibrations on the machining process, thereby significantly improving the stability of the precision of the moving parts on the bed, which is crucial for the machining precision of the ultra-precision small-bore optical grinder, especially during micron-level feeding and single-point grinding and other high-precision machining operations, which can ensure the stability and consistency of the machining precision. In addition, the use of air passive isolators 91 also enhances the overall anti-vibration and vibration reduction characteristics of the machine tool. During the operation of the machine tool, whether the vibration source is from the inside of the machine tool, such as the rotation of the high-speed grinding spindle 50, the grinding force of the grinding wheel, or the external environmental vibration interference, the air passive isolators 91 can effectively absorb and attenuate these vibrations, thereby reducing the negative impact of vibrations on machining precision, which not only improves the surface quality and dimensional accuracy of machined parts, but also prolongs the service life of key components of the machine tool, reduces the maintenance cost and maintenance frequency of the machine tool.

[0038] In an embodiment of the present application, as shown in Figure 2 As shown, the upper portion of the B-axis hydrostatic rotary table 40 is provided with a grinding fine adjustment mechanism 41, and the high-speed grinding spindle 50 is arranged at the upper portion of the grinding fine adjustment mechanism 41. The grinding fine adjustment mechanism 41 is used to adjust the height of the high-speed grinding spindle 50. The grinding fine adjustment mechanism 41 has the following two effects: on the one hand, the grinding fine adjustment mechanism 41 enables the operator to flexibly adjust the height of the high-speed grinding spindle 50 according to different machining requirements and workpiece sizes, which is crucial for machining workpieces of different specifications, especially when machining small-bore optical elements, which can ensure the optimal contact position between the grinding wheel and the workpiece, thereby improving machining efficiency and quality. On the other hand, through the grinding fine adjustment mechanism 41, the operator can accurately control the height of the high-speed grinding spindle 50 to adapt to different machining process requirements. For example, during rough grinding, semi-fine grinding and fine grinding and other different machining stages, the contact position between the grinding wheel and the workpiece may need to be fine-tuned, and the grinding fine adjustment mechanism 41 can meet the demand for precise adjustment, ensuring that each machining stage can achieve the best machining effect.

[0039] In an embodiment of the present application, as shown in Figure 4As shown, the machine tool body 10 is provided with two return water holes 11, the two return water holes 11 are symmetrically arranged, and the two return water holes 11 are respectively located on both sides of the Z-axis hydrostatic guide rail static pressure unit 30 close to one end of the X-axis hydrostatic guide rail static pressure unit 20. A part of the cooling water at the left end of the machine tool body 10 flows upwards first, then flows to the right, and finally flows out through the upper return water hole 11; a part of the cooling water at the right end of the machine tool body 10 flows upwards first, then flows to the left, and finally flows out through the upper return water hole 11; similarly, a part of the cooling water at the left end of the machine tool body 10 flows downwards first, then flows to the right, and finally flows out through the lower return water hole 11, and a part of the cooling water at the right end of the machine tool body 10 flows downwards first, then flows to the left, and finally flows out through the lower return water hole 11.

[0040] The symmetrically arranged return water holes 11 ensure that the flow path and flow distribution of the cooling water on both sides of the machine tool body 10 are uniform, and such uniform cooling effect makes the heating conditions on both sides of the machine tool body 10 consistent, avoiding local temperature differences caused by uneven flow of cooling water; by adopting the symmetrically arranged return water holes 11, the cooling water can uniformly take away the heat generated by the machine tool body 10 during machining, thereby effectively preventing thermal deformation caused by temperature difference and ensuring the structural stability of the machine tool body 10; in addition, in the ultra-precision small-bore optical grinding machine, micron-level machining precision is crucial, and the symmetrically arranged return water holes 11 can ensure that the machine maintains stable machining precision during long-time operation and reduces machining errors caused by thermal deformation.

[0041] In an embodiment of the present application, the workpiece static pressure spindle 70 is provided with an acoustic emission sensor, the acoustic emission sensor is used to detect the AE signal of the grinding wheel, and the acoustic emission sensor is electrically connected with the control cabinet 81. Through the acoustic emission sensor, the AE signal of the grinding wheel can be detected to realize functions such as rapid tool setting, anti-collision and dressing detection. For example, during rapid tool setting, when the grinding wheel approaches the workpiece, a small contact will cause a sudden increase in the acoustic emission signal. By detecting the amplitude jump or energy threshold of the AE signal, the contact time can be determined to achieve high-precision tool setting. Specifically, the grinding wheel rotates at a low speed and slowly approaches the workpiece, and the AE sensor monitors the background noise in real time. When the signal exceeds the preset threshold, the feed is immediately stopped, and the current position is recorded as the “zero point”.

[0042] During anti-collision, abnormal collision (such as grinding wheel hitting the clamp 71) will produce a high-frequency AE pulse signal. By analyzing the burst energy or frequency characteristics (such as frequency domain resonance peak) of the signal, normal cutting and collision can be distinguished. Specifically, a safety threshold (such as AE RMS value) is set, and the signal is monitored in real time. If the threshold is exceeded and the duration is extremely short (ms level), an emergency stop is triggered, and the workpiece static pressure spindle 70 is turned off and retreated in combination with the machine tool control system.

[0043] In the grinding wheel dressing process, when the grinding wheel is passivated or clogged, the RMS value of the AE signal decreases, but the high-frequency component increases (friction intensifies). During the dressing process, the contact between the dressing tool and the grinding wheel produces a unique AE spectral feature. Specifically, the AE baseline of normal grinding is established (such as the RMS average), the signal is monitored in real time, and if the RMS continues to decrease and the high-frequency energy rises, it is determined that the grinding wheel is passivated. During dressing, the start / end point of dressing is identified through the AE signal to ensure consistent dressing amount.

[0044] In an embodiment of the present application, the high-speed grinding spindle 50 is provided with a grinding wheel shaft, and the coordinate point of the grinding wheel clamped by the grinding wheel shaft is located at the intersection of the axis of the high-speed grinding spindle 50 and the axis of the B-axis hydrostatic rotary table 40. This facilitates the software to accurately establish a tool database according to different grinding wheel types and sizes. This accurate tool management method can ensure that the position and posture of the grinding wheel can be accurately recorded and called in different machining tasks, thereby improving the accuracy and repeatability of machining. In addition, when the cutting point approaches the center point of the B-axis hydrostatic rotary table 40, the torque of the B-axis hydrostatic rotary table 40 is more likely to meet the cutting torque formed by the grinding force. This design optimizes the transmission path of the cutting force, so that the B-axis hydrostatic rotary table 40 can more effectively bear and transmit the grinding force during machining, thereby reducing machining errors and equipment wear caused by insufficient torque.

[0045] In an embodiment of the present application, the linear motor of the X-axis hydrostatic guide rail static pressure unit 20 is electrically connected with the control cabinet 81. The control system can calculate the thrust of the linear motor by collecting the current signal of the linear motor, judge the dynamic imbalance of the workpiece static pressure spindle 70, and give the counterweight needed to be added on the workpiece static pressure spindle 70, thereby realizing the dynamic balance adjustment of the workpiece static pressure spindle 70 on the vertical Y-axis 61.

[0046] In an embodiment of the present application, the small-bore optical grinding machine is provided with an inner-outer cooling system, which includes an inner circulation device and an outer circulation device. The inner circulation device includes a high-precision variable-frequency water cooler and a large-flow constant-temperature variable-frequency water cooler. The high-precision variable-frequency water cooler is used to detect the oil temperature fluctuation of the oil outlet of the liquid static pressure guide rail and the B-axis liquid static pressure rotary table 40 in real time, control the temperature of the key components affecting the accuracy of the machine tool system, and provide cooling for the hydraulic oil of the workpiece static pressure spindle 70 and the servo motor of the vertical Y-axis 61. The large-flow constant-temperature variable-frequency water cooler is used to cool the motor of the workpiece static pressure spindle 70 and the motor of the high-speed grinding spindle 50. The large-flow constant-temperature variable-frequency water cooler also provides cooling for the outer circulation device through a heat exchanger, such as cooling for the workpiece machining cutting fluid and overall water spraying of the machine tool. The cutting fluid filtration system is equipped with a heat exchanger, one of which is connected with the variable-frequency water cooler, and the other is connected with the filtered cutting fluid, which is used for cutting fluid cooling. A temperature sensor is arranged at the outlet to monitor the cutting fluid outlet temperature, and the system temperature is manually adjusted to balance.

[0047] As shown in Figures 6 to 9 The present application also provides a machining process of the ultra-precision small-bore optical grinding machine with integrated polishing function. The machining process is based on the ultra-precision small-bore optical grinding machine with integrated polishing function according to any one of the above embodiments, and includes: Coarse grinding and forming. First, the inner spherical outer overhanging column is roughened by a disc grinding wheel, and then the excess material outside the outer circle reference is removed by the disc grinding wheel. Then, the inner spherical surface is roughened by a coarse machining inner profile grinding wheel. In this process, the B-axis liquid static pressure rotary table 40 needs to be rotated to a fixed angle, so as to drive the grinding wheel shaft to form a fixed included angle with the workpiece shaft, wherein the fixed included angle is determined by the size of the workpiece. During the coarse machining of the inner spherical surface, the X-axis and Y-axis positions are fixed, and only the Z-axis needs to be fed. After the coarse machining of the inner spherical surface is completed, the outer spherical outer overhanging column is roughened by the disc grinding wheel. Then, the B-axis liquid static pressure rotary table 40 is rotated so that the included angle between the grinding wheel shaft and the workpiece shaft is 90°. After the Z-axis feed drives the coarse machining outer profile grinding wheel to reach a determined position, the roughening of the outer spherical surface can be realized only by the X-axis feed. Thus, the hemispherical resonator workpiece is initially formed. Semi-fine grinding. The inner spherical surface and the inner spherical column are semi-finely ground by a semi-fine machining inner profile grinding wheel. The outer spherical surface is semi-finely ground by a semi-fine machining outer profile grinding wheel. When the inner and outer spherical surfaces are semi-finely ground, the rotation angle of the B-axis liquid static pressure rotary table 40 is the same as that when the inner and outer spherical surfaces are coarsely ground. Then, the outer spherical column is semi-finely ground by the disc grinding wheel. The inner spherical surface and the inner spherical column are finely ground by using the fine grinding inner contour grinding wheel, the outer spherical surface is finely ground by using the fine grinding outer contour grinding wheel, the rotation angle of the B-axis liquid static pressure rotary table 40 during fine grinding of the inner and outer spherical surfaces is the same as that during coarse grinding of the inner and outer spherical surfaces, and then the outer spherical column is finely ground by using the disc grinding wheel; In each of the above processing processes, the grinding shaft and the workpiece rotate around their own shafts, respectively; The cutting process is performed by using a cutting grinding wheel to cut the outer spherical column to obtain a finished product. The clamp 71 is opened to pull out the rod material to a predetermined length, and then the rod material is clamped by the clamp 71. The above steps are repeated in sequence until the rod material is processed.

[0048] The machining process of the integrated polishing function ultra-precision small caliber optical grinding machine provided by the present application, the machine tool adopts a cup-shaped grinding wheel, and after the B-axis liquid static pressure rotary table 40 is rotated by a certain angle, the fixed angle is fixed, the X-axis liquid static pressure guide rail static pressure unit 20 and the Z-axis liquid static pressure guide rail static pressure unit 30 are cooperatively moved, the micron-level feed is adopted according to the characteristics of brittle optical materials, and the grinding of the inner and outer spherical surfaces of the hemispherical resonator is realized.

[0049] In an embodiment of the present application, in the steps of semi-fine grinding and fine grinding, the end faces of the inner contour grinding wheel and the outer contour grinding wheel are all obliquely cut at a fixed angle α. By adopting the mode of obliquely cutting the machined surface at a fixed angle α, the change of the swing angle of the grinding wheel shaft during grinding can be minimized. This stable processing posture helps to maintain the contact precision between the grinding wheel and the workpiece, avoids processing errors caused by excessive swing of the grinding wheel shaft, and thus improves the processing precision and surface quality. In addition, this processing mode can ensure more uniform contact between the grinding wheel and the workpiece, thereby improving the processing precision and surface quality. Especially when processing complex inner and outer spherical surfaces, this processing mode can effectively reduce processing marks and surface roughness, and improve the overall performance of the workpiece.

[0050] The axis of the inner contour grinding wheel or the outer contour grinding wheel intersects with the axis of the workpiece at the spherical center of the workpiece. By intersecting the axis of the grinding wheel with the axis of the workpiece at the spherical center of the workpiece, it can be ensured that the grinding wheel can still maintain a relatively stable processing trajectory during wear. This processing mode reduces manufacturing errors caused by grinding wheel wear, prolongs the service life of the grinding wheel, and reduces production costs and downtime caused by frequent replacement of the grinding wheel.

[0051] In the machining process, the workpiece static pressure spindle 70 drives the workpiece to rotate at low speed around the axis of the workpiece itself, and the high-speed grinding spindle 50 drives the grinding wheel to rotate at high speed around the axis itself, and the envelope surface of the grinding track of the grinding wheel is the inner and outer spherical surface. The machining method of double-axis rotation makes the grinding track of the grinding wheel more evenly cover the surface of the workpiece, and improves the machining efficiency. At the same time, since the swing angle change of the grinding wheel shaft is reduced, the machining process is more stable, and the downtime caused by adjusting the position of the grinding wheel is reduced.

[0052] Finally, it should be pointed out that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An ultra-precision small-diameter optical grinding machine with integrated polishing function, characterized in that, include: Machine tool body (10); The main support frame assembly includes a main support frame body (90) and a plurality of air passive vibration isolators (91). The plurality of air passive vibration isolators (91) are vertically and spaced apart on the upper part of the main support frame body (90), and the upper ends of the plurality of air passive vibration isolators (91) are connected to the machine tool body (10). X-axis hydrostatic guide rail hydrostatic unit (20), the X-axis hydrostatic guide rail hydrostatic unit (20) is arranged along the X-axis on the upper part of the machine tool body (10); Z-axis hydrostatic guide rail hydrostatic unit (30), the Z-axis hydrostatic guide rail hydrostatic unit (30) is arranged along the Z-axis on the upper part of the machine tool body (10); B-axis hydrostatic rotary table (40), the B-axis hydrostatic rotary table (40) is disposed on the upper part of the Z-axis hydrostatic guide rail hydrostatic unit (30), the upper part of the B-axis hydrostatic rotary table (40) is provided with a high-speed grinding spindle (50), the B-axis hydrostatic rotary table (40) is used to drive the high-speed grinding spindle (50) to rotate around the B-axis, the high-speed grinding spindle (50) is used to install the grinding wheel and drive the grinding wheel to rotate around the C-axis; A vertical drive unit (60) is disposed on the upper part of the X-axis hydrostatic guide rail hydrostatic unit (20); The workpiece hydrostatic spindle (70) is located on one side of the vertical drive unit (60) and above the B-axis hydrostatic rotary table (40). The workpiece hydrostatic spindle (70) is equipped with a clamp (71), which is hollow inside and used to manually extract the bar stock. The clamp (71) holds the bar stock to process multiple workpieces from one bar stock. The vertical drive unit (60) is used to drive the workpiece hydrostatic spindle (70) to move along the Y-axis. The workpiece hydrostatic spindle (70) is equipped with an acoustic emission sensor, which is used to detect the AE signal of the grinding wheel. The acoustic emission sensor enables the machine tool to quickly set the tool and prevent collisions.

2. The ultra-precision small-diameter optical grinding machine with integrated polishing function according to claim 1, characterized in that, The vertical drive unit (60) includes: Mounting bracket (62), which is disposed on the upper part of the X-axis hydrostatic guide rail hydrostatic unit (20); A vertical Y-axis (61) is provided on one side of the mounting bracket (62). The slide of the vertical Y-axis (61) is connected to the workpiece hydrostatic spindle (70). The vertical Y-axis (61) is used to drive the workpiece hydrostatic spindle (70) to move along the Y-axis.

3. The ultra-precision small-diameter optical grinding machine with integrated polishing function according to claim 1, characterized in that, Also includes: Electrical control cabinet; An external support (80) is provided around the outer periphery of the main support frame assembly. An opening is provided on the upper part of the external support (80), and the machine tool body (10) extends out from the opening. The electrical control cabinet is located on the upper part of the external support (80).

4. The ultra-precision small-diameter optical grinding machine with integrated polishing function according to any one of claims 1 to 3, characterized in that, The upper part of the B-axis hydrostatic rotary table (40) is provided with a grinding fine adjustment mechanism (41), and the high-speed grinding spindle (50) is located on the upper part of the grinding fine adjustment mechanism (41).

5. The ultra-precision small-diameter optical grinding machine with integrated polishing function according to any one of claims 1 to 3, characterized in that, The machine tool body (10) is provided with two water return holes (11). The two water return holes (11) are arranged symmetrically and are located on both sides of the Z-axis hydrostatic guide rail hydrostatic unit (30) near the X-axis hydrostatic guide rail hydrostatic unit (20).

6. The ultra-precision small-diameter optical grinding machine with integrated polishing function according to any one of claims 1 to 3, characterized in that, An acoustic emission sensor is provided on the workpiece hydrostatic spindle (70), which is used to detect the AE signal of the grinding wheel.

7. The ultra-precision small-diameter optical grinding machine with integrated polishing function according to any one of claims 1 to 3, characterized in that, The high-speed grinding spindle (50) is equipped with a grinding wheel shaft, and the coordinate point where the grinding wheel is clamped by the grinding wheel shaft is located at the intersection of the axis of the high-speed grinding spindle (50) and the axis of the B-axis hydrostatic turntable (40).

8. A processing technology for an ultra-precision small-diameter optical grinding machine with integrated polishing function, said processing technology being based on the ultra-precision small-diameter optical grinding machine with integrated polishing function as described in any one of claims 1 to 7, characterized in that, include: For rough grinding and forming, firstly, the inner sphere outer cantilever column is roughened using a disc grinding wheel, and then the excess material outside the outer circle reference is removed using the disc grinding wheel; then, the inner sphere is roughened using an inner contour grinding wheel for roughing. During this process, the B-axis hydrostatic turntable (40) needs to be rotated to a fixed angle, thereby driving the grinding wheel rotation axis to form the fixed angle with the workpiece axis, wherein the fixed angle is determined by calculating the workpiece size; during the roughing process of the inner sphere, the X-axis and Y-axis positions are fixed, and only the Z-axis needs to be fed; after the inner sphere is roughened, the outer sphere outer cantilever column is roughened using the disc grinding wheel; then the B-axis hydrostatic turntable (40) rotates so that the angle between the grinding wheel axis and the workpiece axis is 90°. After the Z-axis feed drives the roughing outer contour grinding wheel to a fixed position, the roughing of the outer sphere can be achieved by only the X-axis feed. Thus, the hemispherical harmonic oscillator workpiece is initially formed. Semi-finish grinding is performed by using the inner spherical surface and inner spherical column of the inner contour grinding wheel for semi-finishing; the outer spherical surface is semi-finished by using the outer contour grinding wheel for semi-finishing. When semi-finishing the inner and outer spherical surfaces, the rotation angle of the B-axis hydrostatic turntable (40) is the same as the rotation angle of the B-axis hydrostatic turntable (40) when rough grinding the inner and outer spherical surfaces. Then, the outer spherical column is semi-finished by using the disc grinding wheel. Fine grinding is performed by using an inner contour grinding wheel for fine grinding to grind the inner spherical surface and the inner spherical column, and by using an outer contour grinding wheel for fine grinding to grind the outer spherical surface. When fine grinding the inner and outer spherical surfaces, the rotation angle of the B-axis hydrostatic turntable (40) is the same as the rotation angle of the B-axis hydrostatic turntable (40) when rough grinding the inner and outer spherical surfaces. Then, the outer spherical column is finely ground using the disc grinding wheel. In each of the above processing steps, the grinding axis and the workpiece rotate around their own axes respectively; The outer spherical column is cut off using a cutting grinding wheel to obtain the finished product; Open the clamp (71) to pull out the bar stock to a predetermined length, and then clamp the bar stock again through the clamp (71); Repeat the above steps until the bar stock is processed.

9. The ultra-precision small-diameter optical grinding machine processing technology with integrated polishing function according to claim 8, characterized in that, In the semi-finishing and finishing steps, the end faces of the inner contour grinding wheel and the outer contour grinding wheel are both obliquely intersecting the machined surface at a fixed angle α, and the axis of the inner contour grinding wheel or the outer contour grinding wheel intersects the axis of the workpiece at the center of the workpiece sphere.

Images