A complex optical surface rapid tool and in-situ laser synchronous servo cutting device

Abstract

The present application relates to a kind of complex optical curved surface quick tool and in situ laser synchronous servo cutting device, belong to the technical field of ultra-precision cutting of difficult-to-cut materials and its complex optical curved surface. Including installation support and height adjustment module, quick tool servo cutting and laser installation module, synchronous laser servo irradiation module and optical path adjustment and control module. Advantage is according to complex curved surface geometry characteristics and cutting speed, depth respectively through quick tool servo flexible mechanism and in situ laser synchronous servo flexible mechanism to realize diamond tool movement path and pulse laser strengthening parameter independent adjustment and accurate control, solve the problem of uneven machining quality induced by the mismatch of cutting process parameters and laser strengthening parameters, in situ laser-assisted cutting by laser beam through single crystal diamond tool and directly acting on material cutting deformation area, to eliminate the significant time, space lag between laser enhancement and material cutting deformation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of ultra-precision cutting machining of difficult-to-machine materials and their complex optical surfaces, in particular to a rapid tool and in-situ laser synchronous servo cutting machining device for optical complex surfaces of difficult-to-machine materials. BACKGROUND

[0002] In recent years, optical elements with nanomicrostructures or complex geometric features such as free-form surfaces, such as lens arrays and Fresnel lenses, have been widely used in optoelectronic information, biomedical, aerospace, data storage, new energy, and new sensing technologies, and many other key fields, and have shown broad application prospects and great development potential. Generally speaking, the use of physical or chemical methods such as ultraviolet lithography and etching to manufacture such complex optical elements generally has the disadvantages of limited flexibility and poor flexibility, but mechanical machining methods such as cutting and grinding machining show higher universality and feasibility, and the selectivity and dependence on the properties of the workpiece material are relatively low. At present, the single-crystal diamond turning method based on fast tool servo (FTS) is generally considered to be an ultra-precision machining technology with great development potential and application prospects for creating complex optical elements such as non-rotational symmetric surfaces, and has been widely used in the high-quality and efficient deterministic creation of various nanomicrostructure functional surfaces and complex optical free-form surfaces. However, with the rapid development of science and technology, materials such as single-crystal silicon germanium, silicon carbide, fused quartz, and microcrystalline glass are widely used in the preparation of various high-performance optical components, but such optical materials generally have characteristics such as high brittleness, high hardness, poor thermal conductivity, and low fracture toughness, and are prone to surface and subsurface damage or defects such as cracks, spalling, phase transformation, and residual stress during cutting machining, accompanied by problems such as severe tool wear, low material removal efficiency, poor chip morphology, and large cutting force / heat. Subsequent processes such as grinding and polishing are required to further improve the surface quality, increasing the processing cost and reducing the processing efficiency.

[0003] Therefore, the academic and engineering circles at home and abroad apply the laser-assisted machining technology to the traditional single-point diamond turning method, which can effectively increase the critical cutting depth of various difficult-to-machine materials, reduce the cutting force and heat, reduce tool wear and improve material removal efficiency, thereby effectively inhibiting the damage or defects on the surface and subsurface, and realizing high-quality, high-efficiency and high-precision machining of optical materials. At present, researchers at home and abroad have long been committed to the research of laser-assisted turning and rapid tool servo cutting of difficult-to-machine materials. For example, Professor Chinmaya R. Dandekar of Purdue University in the United States found through turning experiments of aluminum matrix composites that laser-assisted turning has higher tool life and material removal efficiency, and less surface and subsurface damage or defects than traditional turning. Professor Hossein Mohammadi of Western Michigan University in the United States found through cutting experiments of single crystal silicon materials that in-situ laser-assisted turning can obtain a larger critical cutting depth and a lower surface roughness compared with traditional turning. At the same time, C.F. Cheung and others of the Hong Kong Polytechnic University processed optical elements such as free-form surfaces, Fresnel lenses and microlens arrays with extremely high surface quality and surface shape accuracy through rapid tool servo technology.

[0004] At present, although the laser-assisted cutting technology and the rapid tool servo technology have developed rapidly and been widely applied, there are few reports on single crystal diamond cutting technology based on laser irradiation assistance and rapid tool servo, and the synchronization of laser irradiation parameters and tool servo parameters is not considered in the few related researches, so it is difficult to realize high-quality, high-efficiency and precision machining of various complex shape features on the surface of the above high-performance optical materials. The fundamental reason is that in the rapid tool servo cutting process of complex optical surfaces, the cutting depth changes constantly depending on the geometric shape features of the machined surface, but the laser irradiation power, focal position and spot diameter remain constant, which makes the heat absorption efficiency and heat affected zone of the workpiece material change constantly, making it difficult to ensure continuous and effective material removal of difficult-to-machine materials within the plastic / brittle transition critical depth range, and causing extremely adverse effects on the uniformity and consistency of the surface quality of the optical element. SUMMARY

[0005] The present application provides a complex optical curved surface rapid tool and in-situ laser synchronous servo cutting device to solve the problem of unsatisfactory machining surface quality uniformity and consistency caused by the difficulty in synchronous regulation of in-situ laser irradiation and rapid tool servo machining device.

[0006] The technical scheme adopted by the present application is to include an installation support and height adjustment module, a quick tool servo cutting and laser installation module, a synchronous laser servo irradiation module, and an optical path adjustment and control module, wherein two upper wedge-shaped plates in the installation support and height adjustment module are respectively fixed to the middle two sides of the tool servo flexible mechanism of the quick tool servo cutting and laser installation module through four upper wedge-shaped plate fastening bolts, the laser servo flexible mechanism in the synchronous laser servo irradiation module is installed and fixed in the four horizontal round long holes on the two side walls of the U-shaped base of the installation support and height adjustment module through four laser servo mechanism fastening bolts, and the upper mirror in the optical path adjustment and control module is installed and fixed to the lower end of the laser servo flexible mechanism in the synchronous laser servo irradiation module through four upper mirror seat fastening screws.

[0007] The installation support and height adjustment module includes a U-shaped installation base, upper wedge-shaped plates, lower wedge-shaped plates, dovetail grooves, lower wedge-shaped plate fastening bolts, fine adjustment block fastening bolts, wedge-shaped mechanism fine adjustment blocks, wedge-shaped mechanism fine adjustment bolts, front cover plates, front cover plate fastening bolts, rear cover plates, rear cover plate fastening bolts, laser servo mechanism axial position adjustment bolts, upper cover plates, translucent protective observation windows, and upper cover plate fastening bolts, wherein the two upper wedge-shaped plates are respectively installed on the middle two sides of the tool servo flexible mechanism through four upper wedge-shaped plate fastening bolts, the two lower wedge-shaped plates are placed close to the bottom surface and the two side walls of the U-shaped base, the height fine adjustment blocks are installed on the bottom surface of the U-shaped base through two fine adjustment block fastening bolts, the two wedge-shaped mechanism fine adjustment bolts are respectively axially applied to the tail of the two lower wedge-shaped blocks through the threaded holes of the height fine adjustment blocks, the vertical movement of the upper wedge-shaped blocks is driven by the axial movement of the lower wedge-shaped blocks, the cover plates are installed and fixed to the front end of the U-shaped base through six front cover plate fastening bolts, the U-shaped base is connected with the machine tool slide plate through the dovetail groove at the bottom thereof, the upper cover plates are installed and fixed to the top end of the U-shaped base through six upper cover plate fastening bolts, the laser protection glass window is used to directly observe the optical path adjustment and laser focusing conditions, and the focusing mirror height adjustment screw and the up-down mirror spacing adjustment lead screw can be directly adjusted through the corresponding two round long holes, and the rear cover plates are also installed and fixed to the rear end of the U-shaped base through six rear cover plate fastening bolts, and a series of reserved holes and grooves need to be machined.

[0008] The rapid tool servo cutting and laser mounting module comprises a tool servo flexible mechanism, a single crystal diamond tool, a tool fastening screw, a piezoelectric stack driver, an upper wedge-shaped plate fastening bolt, a laser mounting seat fastening bolt, a tool servo mechanism fastening bolt, a piezoelectric driver pre-tightening bolt, an L-shaped displacement measuring block, a capacitive displacement sensor, a sensor mounting upper cover, a sensor upper cover fastening bolt, a sensor base fastening bolt, a sensor mounting base, a displacement measuring block fastening bolt, a fiber laser, a laser mounting seat and a laser fastening bolt, wherein the tool servo flexible mechanism adopts a mixed configuration of a group of high-precision and strong-load straight-round flexible hinges and three groups of large-stroke straight-beam flexible hinges in a "convex" layout configuration, the single crystal diamond tool is installed at the front end of the displacement output platform of the tool servo flexible mechanism by a tool fastening screw, the height of the single crystal diamond tool is realized by the reverse matching of the upper and lower wedge-shaped plates, and the single crystal diamond tool passes through the square hole of the front cover plate; the piezoelectric stack driver is installed and fixed in the axial threaded hole at the rear end of the movement platform of the tool servo flexible mechanism through the bolt on the head of the piezoelectric stack driver, and the tail threaded hole and the pre-tightening bolt of the piezoelectric stack driver are used for installation and pre-tightening of the threaded hole at the end of the tool servo flexible mechanism; the tool servo flexible mechanism is installed and fixed by four tool servo mechanism fastening bolts and vertical round long holes on the two side walls of the U-shaped base; the fiber laser is fixed in the axial opening circular hole of the laser mounting base by two fastening bolts, and is reversely installed below the middle part of the tool servo flexible mechanism along the Z-axis direction by four tool servo mechanism fastening bolts; the sensor mounting base is installed below the two sides of the cantilever at the tool holder position of the tool servo flexible mechanism by two fastening bolts, and the capacitive displacement sensor is axially installed and fixed by the sensor mounting upper cover and two fastening bolts, and the L-shaped displacement measuring block at a certain distance from the capacitive displacement sensor is installed and fixed at the lower front end of the displacement output platform of the tool servo flexible mechanism by a displacement measuring block fastening bolt.

[0009] The synchronous laser servo irradiation module comprises a laser servo flexible mechanism, a piezoelectric stack driver, a laser servo mechanism fastening bolt, a flexible mechanism height adjusting bolt, a mirror spacing adjusting screw, an upper mirror seat fastening screw, a capacitive displacement sensor, a sensor mounting upper cover, a sensor mounting base, a sensor mounting seat fastening bolt, a sensor upper cover fastening bolt and a piezoelectric driver pre-tightening bolt, wherein the laser servo flexible mechanism adopts two groups of high-precision and strong-bearing straight and round flexible hinges to be arranged in a parallelogram configuration, the laser servo flexible mechanism is installed and fixed in four horizontal circular long holes on the two side walls of the U-shaped base of the installation support and height adjustment module through four laser servo mechanism fastening bolts; the piezoelectric stack driver is connected and fixed to the axial threaded hole at the rear end of the laser servo flexible mechanism movement platform through the bolt on the head of the piezoelectric stack driver, and is installed and pre-tightened through the threaded hole at the tail of the piezoelectric stack driver and the piezoelectric driver pre-tightening bolt and the threaded hole at the end of the laser servo flexible mechanism; the spacing adjusting screw passes through the circular hole and the threaded hole of the upper mirror seat and the lower mirror seat; the capacitive displacement sensor is reversely and parallelly installed in the axial circular hole at the front end of the movement platform, and the sensor mounting base is connected and fixed to the top of the laser servo flexible mechanism through two sensor mounting seat fastening bolts, and is installed and fixed with the capacitive displacement sensor through the sensor mounting upper cover and two sensor upper cover fastening bolts.

[0010] The optical path adjustment and control module comprises an upper mirror seat, a lower mirror, a guide slide column, a lower mirror seat, an upper mirror, a focusing mirror support, a laser focusing lens, a focusing mirror frame fastening bolt, a focusing mirror frame height adjusting screw, a guide slide column fastening bolt, an upper mirror angle fine adjustment screw, an upper mirror fastening screw, a lower mirror seat fastening screw, a lower mirror angle fine adjustment screw and a lower mirror fastening screw, wherein the laser focusing lens is installed into the ring groove on both sides of the middle part of the displacement output platform of the laser servo flexible mechanism through the lens support with an open lower end, and the connection and fixation of the lens support and the suspension threaded holes on both sides of the laser servo flexible mechanism are realized through two focusing mirror frame fastening bolts; the upper mirror is installed and fixed into the circular groove of the upper mirror seat through the upper mirror fastening screw, and is installed and fixed to the lower end of the laser servo flexible mechanism through four upper mirror seat fastening screws, and two guide slide columns are installed and fixed into the circular holes on both sides of the upper mirror seat through two fastening screws; the lower mirror is installed and fixed into the circular groove of the lower mirror seat through the lower mirror fastening screw, two guide slide columns and the spacing adjusting screw pass through the circular holes and the threaded holes of the upper mirror seat and the lower mirror seat, and the lower mirror seat is connected and fixed through two lower mirror seat fastening screws; the reflection angles of the upper mirror and the lower mirror are adjusted through the upper mirror angle fine adjustment screw and the lower mirror angle fine adjustment screw which pass through the threaded holes of the upper mirror seat and the lower mirror seat and act on the back of the mirror groove.

[0011] The application provides a single crystal diamond cutting device capable of realizing laser in-situ auxiliary synchronous and rapid tool servo synchronous regulation and control, so as to effectively solve the problems of difficult synchronous regulation of traditional in-situ laser irradiation and rapid tool servo and the induced non-ideal machining surface quality, and the light path modulation module of the device can adjust the relative position of the cutting action area and the laser irradiation area in a large range according to process parameters, and the device has two machining modes of in-situ and non-in-situ laser auxiliary cutting. The laser synchronous servo module will adjust the laser focal point position or material modification depth in real time according to the change rule of the cutting depth in the process of creating machining complex curved surface by the rapid tool servo module, so as to finally realize high-quality, high-efficiency and high-precision cutting machining of various complex optical curved surfaces, especially suitable for hard and brittle materials such as hard alloy, carbonitride and glass ceramic, and has the advantages of compact structure, stable and reliable, high flexibility and strong universality.

[0012] The beneficial effects of the application include:

[0013] The synchronous laser servo irradiation module designed in the application adopts a flexible mechanism with an approximate working stroke and bandwidth as the flexible mechanism of the rapid tool servo cutting and laser installation module. The rapid tool servo cutting and laser installation module needs to output high-frequency reciprocating motion along the axial direction when creating complex optical curved surfaces, so that the cutting action area or the cutting depth changes constantly with the geometric shape of the optical curved surface. At this time, the synchronous laser servo irradiation module also needs to adjust the axial position of the focusing lens and the laser focal point in real time according to the change rule of the cutting depth, so as to always ensure the optimal pose relationship between the cutting action area and the laser irradiation area, and further solve the problem of non-ideal surface quality consistency and uniformity in traditional laser auxiliary cutting. In addition, compared with traditional non-in-situ laser auxiliary cutting, the use of in-situ laser auxiliary cutting can make the laser focal point irradiate the local area of material cutting deformation without time / space lag, so as to effectively reduce the heat affected zone area, improve the laser irradiation enhancement efficiency and inhibit tool wear and damage.

[0014] The piezoelectric actuated flexible mechanism of the rapid tool servo module in the application adopts three groups of straight beam type flexible hinges with different arm lengths in a "convex" configuration, which can obtain a larger movement stroke with a relatively compact structure size; a high-precision and high-stiffness straight circular flexible hinge is used near the tool installation position, so as to effectively improve the guiding accuracy, rebound stiffness and bearing performance of the tool servo flexible mechanism. In addition, the laser is reversely and parallelly installed below the middle part of the tool servo flexible mechanism, and two groups of upper and lower wedge blocks for tool height adjustment are symmetrically arranged on both sides, which can effectively reduce the overall axial size of the device.

[0015] The focusing lens in the application is installed below the middle part of the laser servo flexible mechanism motion platform through a new type of lens support, the motion platform is supported and guided through two groups of high-precision and strong-bearing straight and circular flexible hinges, and the capacitive displacement sensor is reversely arranged in the axial hole of the synchronous laser flexible mechanism motion platform, and the L-shaped displacement measuring block is coaxially installed at the bottom of the tool servo flexible mechanism motion platform. Such arrangement can not only reduce the inertia of the flexible mechanism motion, improve the dynamic characteristics, improve the displacement measurement precision and the compactness of the structure, but also can realize the precise real-time regulation and control of the laser focal point enhanced position following the tool tip cutting trajectory in time and space.

[0016] In the application, the upper and lower two groups of mirrors arranged at ±45° are installed and fixed in the mirror seats with angle fine adjustment function, the upper and lower two groups of mirror seats are connected and fixed through guide slide columns and spacing adjustment lead screws, and then are installed and fixed below the end of the laser servo flexible mechanism, the focusing lens is also arranged in the lens support below the flexible mechanism motion platform, by screwing the corresponding adjusting bolts, the vertical, horizontal and axial positions of the focusing lens, the spacing and reflection angle of the upper and lower two groups of mirrors can be coarsely and finely adjusted, and then the adjustment, reversing and shaping of the laser light path system are realized, the best irradiation efficiency of the laser focal point and the coaxiality of the light path system are effectively ensured, the control precision is high, the range is large and the operation is simple. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structural schematic diagram of the application;

[0018] Figure 2 is a structural schematic diagram of the application;

[0019] Figure 3 is a structural schematic diagram of the quick tool servo cutting and laser installation module of the application;

[0020] Figure 4 is a structural schematic diagram of the synchronous laser servo irradiation module and the light path adjustment and control module of the application;

[0021] Figure 5 is a rear view of Figure 4 ;

[0022] Figure 6 is a structural schematic diagram of the installation support and height adjustment module of the application;

[0023] Figure 7 is a structural schematic diagram of the laser installation module and the light path adjustment and control module of the application;

[0024] Figure 8 is a top view of the quick tool servo cutting and laser installation module of the application;

[0025] Figure 9 is the top view of the synchronous laser servo irradiation module of the present application;

[0026] Figure 10 is the structural schematic diagram of the focusing mirror support, laser focusing lens and focusing mirror frame height adjusting screw of the present application;

[0027] Figure 11 is the structural schematic diagram of the upper mirror and the upper mirror seat of the present application;

[0028] Figure 12 is the side view of the upper mirror and the upper mirror seat of the present application;

[0029] Figure 13 is the structural schematic diagram of the laser mount of the present application;

[0030] Figure 14 is the structural schematic diagram of the rear cover plate of the present application;

[0031] Figure 15 is the structural schematic diagram of the tool servo flexible mechanism of the present application;

[0032] Figure 16 is the structural schematic diagram of the laser servo flexible mechanism of the present application;

[0033] BRIEF DESCRIPTION OF DRAWINGS: Mounting support and height adjustment module 1, quick tool servo cutting and laser mounting module 2, synchronous laser servo irradiation module 3, optical path adjustment and control module 4; 101-U shaped mounting base; 102- upper wedge plate (2); 103- lower wedge plate (2); 104- dovetail groove; 105- lower wedge plate fastening bolt (4); 106- fine adjustment block fastening bolt (2); 107- wedge mechanism fine adjustment block; 108- wedge mechanism fine adjustment bolt (2); 109- front cover plate; 110- front cover plate fastening bolt (4); 111- rear cover plate; 112- rear cover plate fastening bolt (6); 113- laser servo mechanism axial position adjustment bolt (2); 114- upper cover plate; 115- translucent protective observation window; 116- upper cover plate fastening bolt (6); 201- tool servo flexible mechanism; 202- single crystal diamond tool; 203- tool fastening screw; 204- piezoelectric stack driver; 205- upper wedge plate fastening bolt (4); 206- laser mount fastening bolt (4); 207- tool servo mechanism fastening bolt (4); 208- piezoelectric driver pre-tightening bolt; 209- L-shaped displacement measuring block; 210- capacitive displacement sensor; 211- sensor mounting upper cover; 212- sensor upper cover fastening bolt (2); 213- sensor base fastening bolt (2); 214- sensor mounting base; 215- displacement measuring block fastening bolt; 216- fiber laser; 217- laser mount; 218- laser fastening bolt (2); 301- laser servo flexible mechanism; 302- piezoelectric stack driver; 303- laser servo mechanism fastening bolt (4); 304- flexible mechanism height adjustment bolt (4); 305- mirror spacing adjustment lead screw; 306- upper mirror mount fastening screw (4); 307- capacitive displacement sensor; 308- sensor mounting upper cover; 309- sensor mounting base; 310- sensor mounting base fastening bolt (2); 311- sensor upper cover fastening bolt (2); 312- piezoelectric driver pre-tightening bolt; 401- upper mirror mount; 402- lower mirror; 403- guide slide post (2); 404- lower mirror mount; 405- upper mirror; 406- focusing mirror holder; 407- laser focusing lens; 408- focusing mirror holder fastening bolt (2); 409- focusing mirror holder height adjustment screw; 410- guide slide post fastening bolt (2); 411- upper mirror angle fine adjustment screw; 412- upper mirror fastening screw; 413- lower mirror mount fastening screw (2); 414- lower mirror angle fine adjustment screw; 415- lower mirror fastening screw. DETAILED DESCRIPTION

[0034] As Figure 1 , 2As shown, it includes installation support and height adjustment module 1, quick tool servo cutting and laser installation module 2, synchronous laser servo irradiation module 3 and light path adjustment and control module 4, wherein two upper wedge-shaped plates 102 in installation support and height adjustment module 1 are respectively fixed to the middle two sides of tool servo flexible mechanism 201 of quick tool servo cutting and laser installation module 2 through four upper wedge-shaped plate fastening bolts 205, laser servo flexible mechanism 301 in synchronous laser servo irradiation module 3 is installed and fixed in four horizontal round long holes on the two side walls of U-shaped base 101 of installation support and height adjustment module 1 through four laser servo mechanism fastening bolts 303; upper mirror 405 in light path adjustment and control module 4 is installed and fixed to the lower end of laser servo flexible mechanism 301 in synchronous laser servo irradiation module 3 through four upper mirror seat fastening screws 306.

[0035] As shown in Figure 1 , 2 , 6, 14, installation support and height adjustment module 1 includes U-shaped installation base 101, upper wedge-shaped plate 102, lower wedge-shaped plate 103, dovetail groove 104, lower wedge-shaped plate fastening bolt 105, fine adjustment stop block fastening bolt 106, wedge mechanism fine adjustment stop block 107, wedge mechanism fine adjustment bolt 108, front cover plate 109, front cover plate fastening bolt 110, rear cover plate 111, rear cover plate fastening bolt 112, laser servo mechanism axial position adjustment bolt 113, upper cover plate 114, translucent protective observation window 115 and upper cover plate fastening bolt 116, wherein two upper wedge-shaped plates 102 are respectively installed on the middle two sides of tool servo flexible mechanism 201 through four upper wedge-shaped plate fastening bolts 205, two lower wedge-shaped plates 103 are placed close to the bottom surface and two side walls of U-shaped base 101, height fine adjustment stop block 107 is installed on the bottom surface of U-shaped base 101 through two fine adjustment stop block fastening bolts 106, two wedge mechanism fine adjustment bolts 108 are respectively axially applied to the tail of two lower wedge-shaped blocks 102 through the threaded holes of height fine adjustment stop block 107, and the vertical movement of upper wedge-shaped block 103 is driven by the axial movement of lower wedge-shaped block 102; cover plate 109 is installed and fixed to the front end of U-shaped base 101 through six front cover plate fastening bolts 110, U-shaped base 101 is connected with the slide plate of machine tool through dovetail groove 104 at the bottom; upper cover plate 114 is installed and fixed to the top end of U-shaped base 101 through six upper cover plate fastening bolts 116, and laser protection glass window 115 is used to directly observe the light path adjustment and laser focusing conditions, and the height adjustment screw 409 of focusing mirror and the distance adjustment lead screw 305 between upper and lower mirrors can be directly adjusted through the corresponding two round long holes; rear cover plate 111 is also installed and fixed to the rear end of U-shaped base 101 through six rear cover plate fastening bolts 112, and a series of reserved holes and grooves need to be machined.

[0036] As shown in Figure 1 ,2 , 3, 7, 8, 13, 15, the rapid tool servo cutting and laser installation module 2 includes tool servo flexible mechanism 201, single crystal diamond tool 202, tool fastening screw 203, piezoelectric stack driver 204, upper wedge plate fastening bolt 205, laser installation seat fastening bolt 206, tool servo mechanism fastening bolt 207, piezoelectric driver pre-tightening bolt 208, L-shaped displacement measuring block 209, capacitive displacement sensor 210, sensor installation upper cover 211, sensor upper cover fastening bolt 212, sensor base fastening bolt 213, sensor installation base 214, displacement measuring block fastening bolt 215, fiber laser 216, laser installation seat 217 and laser fastening bolt 218, wherein the rapid tool servo flexible mechanism 201 adopts a mixed configuration of a group of high-precision and strong-load straight circular flexible hinges and three groups of large-stroke straight beam type flexible hinges in a "convex" layout configuration, the single crystal diamond tool 202 is installed at the front end of the displacement output platform (i.e. the tool holder) of the tool servo flexible mechanism 201 by using a tool fastening screw 203, the height of the single crystal diamond tool 202 is realized by the reverse matching of the upper and lower wedge plates 102 and 103, and passes through the square hole of the front cover plate 109; the piezoelectric stack driver 204 is installed and fixed in the axial threaded hole at the rear end of the motion platform of the tool servo flexible mechanism 201 through the bolt on its head, and is installed and pre-tightened through its tail threaded hole and pre-tightening bolt 208 and the threaded hole at the end of the tool servo flexible mechanism 201; the tool servo flexible mechanism 201 is installed and fixed by using four tool servo mechanism fastening bolts 207 and vertical circular long holes on the side walls of the U-shaped base 101; the fiber laser 216 is fixed in the axial opening circular hole of the laser installation base 217 by using two fastening bolts 218, and is reversely installed below the middle part of the tool servo flexible mechanism 201 along the Z-axis direction by four tool servo mechanism fastening bolts 207; the sensor installation base 214 is installed below the two sides of the cantilever at the tool holder position of the tool servo flexible mechanism 201 by using two fastening bolts 213, and is axially installed and fixed with the capacitive displacement sensor 210 by cooperating with the sensor installation upper cover 211 and two fastening bolts 212, while the L-shaped displacement measuring block 209 at a certain distance from the capacitive displacement sensor 210 is installed and fixed at the lower front end of the displacement output platform (i.e. the tool holder) of the tool servo flexible mechanism 201 by using a displacement measuring block fastening bolt 215.

[0037] As Figure 1 , 2, 4, 5, 9, 16, the synchronous laser servo irradiation module 3 includes laser servo flexible mechanism 301, piezoelectric stack driver 302, laser servo mechanism fastening bolt 303, flexible mechanism height adjustment bolt 304, mirror spacing adjustment screw 305, upper mirror seat fastening screw 306, capacitive displacement sensor 307, sensor installation upper cover 308, sensor installation base 309, sensor installation base fastening bolt 310, sensor upper cover fastening bolt 311 and piezoelectric driver pre-tightening bolt 312, wherein the laser servo flexible mechanism 301 adopts two groups of high-precision and strong bearing straight circular flexible hinges to configure in the form of parallelogram, the laser servo flexible mechanism 301 is installed and fixed in the four horizontal circular long holes on the two side walls of the U-shaped base 101 of the installation support and height adjustment module 1 by four laser servo mechanism fastening bolts 303;The piezoelectric stack driver 302 is connected and fixed to the axial threaded hole at the rear end of the movement platform of the laser servo flexible mechanism 301 through the bolt on its head, and is installed and pre-tightened with the threaded hole at the end of the laser servo flexible mechanism 301 through its tail threaded hole and piezoelectric driver pre-tightening bolt 312;The spacing adjustment screw 305 passes through the round hole and threaded hole of the upper mirror seat 401 and the lower mirror seat 404;The capacitive displacement sensor 307 is reversely and parallelly installed in the axial circular hole at the front end of its movement platform, the sensor installation base 309 is connected and fixed to the top of the laser servo flexible mechanism 301 by two sensor installation base fastening bolts 310, and cooperates with the sensor installation upper cover 308 and two sensor upper cover fastening bolts 311 to realize the installation and fixation of the capacitive displacement sensor 307.

[0038] As Figure 1 、 2, 4, 5, 7, 10, 11, 12, the light path adjustment and control module 4 includes the upper mirror seat 401, the lower mirror 402, the guide slide column 403, the lower mirror seat 404, the upper mirror 405, the focusing mirror support 406, the laser focusing lens 407, the focusing mirror frame fastening bolt 408, the focusing mirror frame height adjustment screw 409, the guide slide column fastening bolt 410, the upper mirror angle fine adjustment screw 411, the upper mirror fastening screw 412, the lower mirror seat fastening screw 413, the lower mirror angle fine adjustment screw 414 and the lower mirror fastening screw 415, wherein the laser focusing lens 407 is installed into the ring groove on both sides of the middle part of the displacement output platform of the laser servo flexible mechanism 301 by using the lens support 406 with an open lower end, and the lens support 406 is connected and fixed with the cantilever threaded holes on both sides of the laser servo flexible mechanism 301 by using two focusing mirror frame fastening bolts 408; the upper mirror 405 is installed and fixed into the round groove of the upper mirror seat 401 by using the upper mirror fastening screw 412, and is installed and fixed to the lower part of the end of the laser servo flexible mechanism 301 by using four upper mirror seat fastening screws 306, and the two guide slide columns 403 are installed and fixed into the round holes on both sides of the upper mirror seat 401 by using two fastening bolts 410; the lower mirror 402 is installed and fixed into the round groove of the lower mirror seat 404 by using the lower mirror fastening screw 415, the two guide slide columns 403 and the spacing adjustment lead screw 305 pass through the round holes and threaded holes of the upper mirror seat 401 and the lower mirror seat 404, and the lower mirror seat 404 is connected and fixed by using two lower mirror seat fastening screws 413; the reflection angles of the upper mirror 405 and the lower mirror 402 are adjusted by the upper mirror angle fine adjustment screw 411 and the lower mirror angle fine adjustment screw 414 which pass through the threaded holes of the upper mirror seat 401 and the lower mirror seat 404 and act on the back of the mirror groove.

[0039] Working principle and operation process

[0040] The device realizes the arbitrary regulation and control between the workpiece, the cutting interface region of the tool and the irradiation position of the laser spot focus through the fast tool servo cutting with the similar bandwidth frequency of the motion stroke and the laser installation module and the synchronous laser servo irradiation module, so as to ensure that the focal position of the laser irradiation can be adjusted according to the real-time changes of the process parameters such as the cutting depth and the speed when the complex optical curved surface is created, and the high requirements of the hard and brittle material complex optical element on the uniformity and consistency of the machining surface quality and the like can be met in the traditional laser-assisted cutting process because the focal irradiation position is uncontrollable or can only be simply moved equidistantly with the tool. In addition, the laser enhanced focus point of the traditional laser-assisted cutting machining method is usually located in the local region of the cutting speed direction and a certain distance from the tool cutting point, which causes the significant time and space lag between the laser irradiation and the material cutting deformation, and is accompanied by the disadvantages of large heat-affected zone and low strengthening efficiency, so the in-situ laser-assisted cutting is proposed in the application, that is, the laser beam passes through the single crystal diamond tool and then directly irradiates the material cutting deformation region, which can effectively eliminate the above-mentioned time / space lag and the adverse effects induced thereby.

[0041] After the bolt 108 passes through the fine adjustment block 107 and pushes the two lower wedge-shaped plates 103 which are symmetrically arranged and close to the bottom surface and the side wall surface of the U-shaped base, the two upper wedge-shaped plates 102 symmetrically installed on the bottom of the tool servo flexible mechanism 201 are driven to move in the height direction, so as to realize the fine adjustment of the height of the diamond tool 202, and then the tool servo flexible mechanism 201 is fastened in the vertical long hole of the side wall of the U-shaped base 101 by using the four fastening bolts 207; the laser servo flexible mechanism 301 first adjusts the axial position of the focusing lens 407 according to the focal length parameters of the focusing lens 407 by using the two adjusting bolts 113 matched with the threaded holes of the rear cover plate 111, and then the focusing lens 407 is fastened in the horizontal long hole of the side wall of the U-shaped base 101 by using the four fastening bolts 408, so that the upper and lower mirrors 405 and 402 and the attached structures installed at the ends thereof can also reach the corresponding axial positions; the square hole reserved on the front cover plate 109 needs to provide sufficient movement space for the diamond tool, and a series of reserved holes and grooves should also be machined on the rear cover plate 111, so that the piezoelectric actuator pre-tightening bolt 208, the upper and lower mirror angle adjusting screws 411 and 414, the tool height wedge-shaped mechanism fine adjustment bolt 304 and the axial position adjusting bolt 113 of the laser servo flexible mechanism can be directly rotated without removing the rear cover plate 111.

[0042] 3, open the fiber laser 216, emit a beam of Gaussian laser, after the coaxial +45 ° installed under the mirror 402, reflected to the coaxial-45 ° installed on the mirror 405, after the second reflection along the optical axis direction irradiation to the center of the laser focusing lens 407 region; twist four adjusting bolts 304 reasonable adjustment of laser servo flexible mechanism 301 and installed at the end of the upper and lower mirror 405 and 402 vertical height, control the position and attitude of laser servo flexible mechanism and its motion platform in the middle of the focusing lens, to ensure that the laser focal point irradiation area and the workpiece cutting deformation area has the best relative position and incident angle; directly adjust the focusing mirror height adjusting screw 409 and the distance between the upper and lower mirror adjusting screw 305, along the guide slide column 403 axial reasonable adjustment of the distance between the upper and lower mirror 405 and 402 and the position of the focusing lens, so as to ensure the optimality of the laser focal point and the coaxiality of the optical path system; twist the adjusting bolt 411 and 414, the reflection angle of the upper and lower mirror 405 and 402 is adjusted slightly, to ensure that the laser beam emitted by the laser is reflected twice by the upper mirror and the lower mirror arranged below the end of the laser servo flexible mechanism at ± 45 ° respectively, and the light path system is reversed by 180 °; through the laser protection glass window 115, the light path adjustment and laser focusing are directly observed, and finally the laser spot accurately passes through the single crystal diamond tool 202 and irradiates the tool-workpiece cutting interface.

[0043] 4, rotate the piezoelectric driver pre-tightening bolt 208, generate pre-tightening force to the piezoelectric stack driver 204; open the capacitance displacement sensor 210, piezoelectric stack driver 204 and its related control software, directly drive the flexible hinge of the tool servo flexible mechanism 201 to produce the required elastic deformation, so that its motion platform and diamond tool obtain high frequency reciprocating motion along the Z axis direction, use the capacitance displacement sensor 210 to detect and collect the tool motion position in real time, at the same time, feedback the position signal to the controller to build a closed loop control system, improve the tracking accuracy of the fast tool servo cutting and laser installation module for complex curved surface tool path.

[0044] 5、open the capacitive displacement sensor 307, piezoelectric stack driver 302 and its related operating software, according to the real-time position signal of the tool feedback by capacitive displacement sensor 201, drive the flexible hinge of laser synchronous flexible mechanism 301 to produce the required elastic deformation, make the focusing lens 407 in the middle of the moving platform get high frequency reciprocating motion along the Z axis direction, realize the synchronous motion of laser focal point, through the real-time detection and collection of the axial position of focusing lens 407 by the reverse installation of capacitive displacement sensor 307, and feedback the position signal to the controller to build a closed loop control system, improve the control precision of the laser focal point irradiation position by the rapid tool servo cutting and laser installation module, ensure the reasonable position relationship between the tool cutting interface and the laser irradiation focal point.

[0045] 6、workpiece is clamped in the main shaft of machine tool for rotary motion, and the cutting device is installed on the slide plate of machine tool for transverse feeding. The complex curved surface tool path planned in advance is introduced into the control system, and the diamond tool and the laser focal point are driven to perform accurate cooperative motion, so that the creation processing of complex optical curved surface is finally completed.

Claims

1. A complex optical surface fast tool servo and in-situ laser servo cutting device, characterized in that: The installation support and height adjustment module, the quick tool servo cutting and laser installation module, the synchronous laser servo irradiation module and the optical path adjustment and control module are included, wherein the two upper wedge-shaped plates in the installation support and height adjustment module are respectively fixed to the middle two sides of the tool servo flexible mechanism of the quick tool servo cutting and laser installation module through four upper wedge-shaped plate fastening bolts, the laser servo flexible mechanism in the synchronous laser servo irradiation module is installed and fixed in the four horizontal circular long holes on the two side walls of the U-shaped base of the installation support and height adjustment module through four laser servo mechanism fastening bolts, and the upper mirror in the optical path adjustment and control module is installed and fixed to the lower end of the laser servo flexible mechanism in the synchronous laser servo irradiation module through four upper mirror seat fastening screws. The installation support and height adjustment module includes a U-shaped installation base, upper wedge-shaped plates, lower wedge-shaped plates, fine adjustment block fastening bolts, wedge-shaped mechanism fine adjustment blocks and wedge-shaped mechanism fine adjustment bolts, wherein the two upper wedge-shaped plates are respectively installed on the middle two sides of the tool servo flexible mechanism through four upper wedge-shaped plate fastening bolts, the two lower wedge-shaped plates are placed close to the bottom surface and the two side walls of the U-shaped base, the height fine adjustment block is installed on the bottom surface of the U-shaped base through two fine adjustment block fastening bolts, and the two wedge-shaped mechanism fine adjustment bolts are respectively axially applied to the tail portions of the two lower wedge-shaped plates through the threaded holes of the height fine adjustment block, and the vertical movement of the upper wedge-shaped plates is driven by the axial movement of the lower wedge-shaped plates. The quick tool servo cutting and laser installation module includes a tool servo flexible mechanism, a single crystal diamond tool, a piezoelectric stack driver, a capacitive displacement sensor one and a sensor installation base one, wherein the tool servo flexible mechanism adopts a mixed configuration of a group of high-precision and strong-load straight circular flexible hinges and three groups of large-stroke straight beam flexible hinges arranged in a "convex" layout, the single crystal diamond tool is installed at the front end of the displacement output platform of the tool servo flexible mechanism through a tool fastening screw, the height of the single crystal diamond tool is realized through the reverse cooperation of the upper and lower wedge-shaped plates, and passes through the square hole of the front cover plate, the piezoelectric stack driver is installed and fixed in the axial threaded hole at the rear end of the movement platform of the tool servo flexible mechanism through the bolt at the head thereof, and is installed and pre-tightened through the threaded hole at the tail thereof and the pre-tightening bolt and the threaded hole at the end of the tool servo flexible mechanism; the capacitive displacement sensor one is installed on the sensor installation base one. The synchronous laser servo irradiation module comprises a laser servo flexible mechanism, a piezoelectric stack driver, a laser servo mechanism fastening bolt, a flexible mechanism height adjustment bolt, a capacitive displacement sensor two and a sensor mounting base two, wherein the laser servo flexible mechanism adopts two groups of high-precision and strong-bearing straight-circular flexible hinges to be configured in a parallelogram configuration, the laser servo flexible mechanism is installed and fixed in four horizontal circular holes on the two side walls of the U-shaped base of the installation support and height adjustment module through four laser servo mechanism fastening bolts; the piezoelectric stack driver is connected and fixed to the axial threaded hole at the rear end of the laser servo flexible mechanism movement platform through the bolt on the head of the piezoelectric stack driver, and is installed and pre-tightened by using the tail threaded hole and the piezoelectric driver pre-tightening bolt and the threaded hole at the end of the laser servo flexible mechanism, and the capacitive displacement sensor two is installed on the sensor mounting base two. The light path adjustment and control module comprises a lower mirror, an upper mirror, a focusing lens holder and a laser focusing lens, wherein the laser focusing lens is installed into the ring groove on both sides of the middle part of the displacement output platform of the laser servo flexible mechanism by using the focusing lens holder with an open lower end, the lower mirror and the upper mirror are installed below the end of the laser servo flexible mechanism and are arranged at ± 45°, respectively.

2. A complex optical surface fast tool servo and in-situ laser servo cutting device according to claim 1, characterized in that: The installation support and height adjustment module further comprises a dovetail groove, a lower wedge plate fastening bolt, a front cover plate, a front cover plate fastening bolt, a rear cover plate, a rear cover plate fastening bolt, a laser servo mechanism axial position adjustment bolt, an upper cover plate, a translucent protective observation window and an upper cover plate fastening bolt, wherein the cover plate is installed and fixed to the front end of the U-shaped base by using six front cover plate fastening bolts, the U-shaped base is connected with the machine tool slide by using the dovetail groove at the bottom of the U-shaped base; the upper cover plate is installed and fixed to the top end of the U-shaped base by using six upper cover plate fastening bolts, and the light path adjustment and laser focusing condition are directly observed by using the laser protection glass window, the rear cover plate is also installed and fixed to the rear end of the U-shaped base by using six rear cover plate fastening bolts, and a series of reserved holes and grooves need to be machined.

3. A complex optical surface fast tool servo and in-situ laser servo cutting device according to claim 1, characterized in that: The rapid tool servo cutting and laser installation module further comprises a tool fastening screw, an upper wedge-shaped plate fastening bolt, a laser installation base fastening bolt, a tool servo mechanism fastening bolt, a piezoelectric driver pre-tightening bolt, an L-shaped displacement measuring block, a sensor installation upper cover, a sensor upper cover fastening bolt, a sensor base fastening bolt, a displacement measuring block fastening bolt, an optical fiber laser, a laser installation base, and a laser fastening bolt, wherein the tool servo flexible mechanism is installed and fixed by means of four tool servo mechanism fastening bolts and vertical circular long holes on the two side walls of the U-shaped base; the optical fiber laser is fixed in the axial opening circular hole of the laser installation base by means of two fastening bolts, and is reversely installed in the lower middle part of the tool servo flexible mechanism along the Z-axis direction by means of the four tool servo mechanism fastening bolts; the sensor installation base is installed below the two sides of the cantilever at the tool holder position of the tool servo flexible mechanism by means of two fastening bolts, and is axially installed and fixed with the capacitor displacement sensor I by means of the sensor installation upper cover and two fastening bolts, while the L-shaped displacement measuring block at a certain distance from the capacitor displacement sensor I is installed and fixed at the lower front end of the displacement output platform of the tool servo flexible mechanism by means of a displacement measuring block fastening bolt.

4. A complex optical surface fast tool servo and in-situ laser servo cutting device according to claim 1, wherein: The synchronous laser servo irradiation module further comprises a mirror spacing adjustment screw, an upper mirror seat fastening screw, a sensor installation upper cover, a sensor installation base fastening bolt, a sensor upper cover fastening bolt, and a piezoelectric driver pre-tightening bolt, wherein the spacing adjustment screw passes through the circular hole and the threaded hole of the upper mirror seat and the lower mirror seat; the capacitor displacement sensor II is reversely and parallelly installed in the axial circular hole at the front end of the movement platform, the sensor installation base II is connected and fixed to the top of the laser servo flexible mechanism by means of two sensor installation base fastening bolts, and is installed and fixed with the capacitor displacement sensor II by means of the sensor installation upper cover and two sensor upper cover fastening bolts.

5. A complex optical surface fast tool servo and in-situ laser servo cutting device according to claim 1, wherein: The light path adjusting and controlling module further comprises an upper mirror seat, guide slide columns, a lower mirror seat, focusing lens holder fastening bolts, focusing lens holder height adjusting screws, guide slide column fastening bolts, an upper mirror angle fine adjustment screw, an upper mirror fastening screw, a lower mirror seat fastening screw, a lower mirror angle fine adjustment screw and a lower mirror fastening screw, wherein two focusing lens holder fastening bolts are used to connect and fix the lens holder and the two side cantilever threaded holes of the laser servo flexible mechanism; the upper mirror is installed and fixed into the upper mirror seat circular groove by the upper mirror fastening screw, and is installed and fixed to the lower end of the laser servo flexible mechanism by four upper mirror seat fastening screws, and two guide slide columns are installed and fixed into the circular holes on the two sides of the upper mirror seat by two fastening screws; the lower mirror is installed and fixed into the lower mirror seat circular groove by the lower mirror fastening screw, two guide slide columns and the spacing adjusting screw pass through the circular holes and the threaded holes of the upper mirror seat and the lower mirror seat, and the lower mirror seat is connected and fixed by two lower mirror seat fastening screws; the reflection angles of the upper mirror and the lower mirror are respectively adjusted by the upper mirror angle fine adjustment screw and the lower mirror angle fine adjustment screw which pass through the threaded holes of the upper mirror seat and the lower mirror seat and act on the back of the mirror grooves.

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