High-precision lead screw thread laser machining device and machining method

Abstract

The invention relates to a high-precision lead screw thread laser machining device and method, and belongs to the technical field of ultrafast laser microstructure machining, modulated machining laser beams are used for multi-head thread machining, a laser light source is subjected to beam splitting according to the number of multi-head threads, the machining laser beams obtained after beam splitting have the same machining capacity, and the machining efficiency is improved. When acting on a material, the etching capability is consistent, so that the etching morphology difference of each thread is small, and the processing precision is improved. Compared with the mode that threads are machined one by one in a machining mode, the consistency of the threads machined through laser beam splitting is better, the quality of all the threads is similar, and due to synchronous machining, the machining efficiency is improved exponentially. In addition, based on the characteristics of the laser beams, the light knife formed by the machining laser beams cannot be abraded due to contact with the materials, and the machining precision is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of ultrafast laser microstructure processing, and specifically relates to a high-precision lead screw thread laser processing device and a processing method. Background Art

[0002] High-precision screws (such as ball screws or roller screws) are mechanical transmission devices that can convert the rotational motion of a servo motor into linear motion. They have the advantages of strong load-bearing capacity, high axial stiffness, high transmission efficiency, and long service life. They are widely used in precision CNC machine tools, heavy machinery, medical equipment, weapons and equipment, aerospace, and other fields.

[0003] The thread processing of high-precision lead screws is usually based on CNC machine tools, using two mechanical processing methods: thread cutting and thread rolling. The principle is to process by turning or grinding, such as drilling, milling, rolling and spiral milling. It is difficult to process complex-shaped threads using this processing method, or customized tools and processing equipment are required, which increases the processing cost and difficulty. When processing threads, the pitch needs to be precisely controlled, resulting in longer processing time, and long-term processing will cause the forming tool to wear and age, which will affect the subsequent processing accuracy. In addition, when processing more complex multi-threads, due to the difference in the degree of wear between different forming tools, the accuracy of multiple threads is completely different. Even if the use time and material of the forming tool are the same, the consistency of the processing effect cannot be guaranteed, and it is difficult to guarantee the processing accuracy of each thread.

[0004] Therefore, a high-precision lead screw thread laser processing device and processing method are needed to improve the processing accuracy and processing efficiency of the high-precision lead screw thread. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a high-precision screw thread laser processing device and processing method. The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0006] The present invention provides a high-precision lead screw thread laser processing device, comprising: a laser, an optical path transmission module and a rotation feeding module; wherein the laser is used to output a laser light source; the optical path transmission module is arranged behind the laser, and is used to split and shape the laser light source to obtain a plurality of processing laser beams; the plurality of processing laser beams are arranged at intervals along the circumferential direction, and the plurality of processing laser beams simultaneously etches the surface of a rod-shaped workpiece; the rotation feeding module is used to clamp the rod-shaped workpiece, and drive the rod-shaped workpiece to perform rotational motion and feed motion along the axial direction.

[0007] In one embodiment of the present invention, the laser is a femtosecond laser, and the laser output laser light source realizes subtractive processing through ionization.

[0008] In one embodiment of the present invention, a plurality of the processing laser beams are arranged at equal intervals, and each of the processing laser beams is parallel to the surface normal direction of the rod-shaped workpiece.

[0009] In one embodiment of the present invention, the morphology of each of the processing laser beams is consistent with the morphology of the thread groove of the high-precision lead screw to be processed.

[0010] In one embodiment of the present invention, the rotating feed module includes: a clamping chuck and a multi-axis rotating platform; wherein the clamping chuck is arranged on the multi-axis rotating platform for clamping the rod-shaped workpiece; the multi-axis rotating platform includes at least two rotating axes for driving the rod-shaped workpiece to perform rotational motion and feeding motion along the axial direction.

[0011] In one embodiment of the present invention, the high-precision lead screw thread laser processing device also includes: a dust removal module and an air path auxiliary module; wherein the dust removal module is used for adsorption and dust removal; the air path auxiliary module is used for auxiliary blowing to remove the plasma generated by the laser etching process.

[0012] The present invention also provides a high-precision lead screw thread laser processing method, comprising:

[0013] Step 1: Split the laser light source into several processing laser beams according to the number of thread heads of the high-precision lead screw to be processed;

[0014] Step 2: adjusting the shape of the processing laser beam according to the shape of the thread groove of the high-precision lead screw to be processed;

[0015] Step 3: Position and adjust the rod-shaped workpiece and clamp it;

[0016] Step 4: rotating the rod-shaped workpiece, and performing synchronous etching processing with a plurality of the processing laser beams, wherein the cutting tool is inserted from the first end of the rod-shaped workpiece in the axial direction and fed to the second end at a uniform speed to exit the workpiece, thereby completing the etching processing of the first etching line of the first processing layer;

[0017] Step 5: Rotate the rod-shaped workpiece in the opposite direction, and perform etching processing synchronously by using a plurality of processing laser beams, wherein the cutting tool is inserted from the second end of the rod-shaped workpiece in the axial direction and fed to the first end at a uniform speed to exit the workpiece, thereby completing the etching processing of the second etching line of the first processing layer;

[0018] Step 6: Repeat steps 3 and 4 until the etching process of the first processing layer is completed;

[0019] Step 7: lowering the focal plane of the processing laser beam several times along the surface normal direction of the rod-shaped workpiece, and repeating steps 4 to 6 until the etching process of the next processing layer is completed;

[0020] Step 8: Repeat step 7 until the etching process of the entire morphology of the thread groove of the high-precision lead screw to be processed is completed.

[0021] In one embodiment of the present invention, step 2 comprises:

[0022] Step 2.1: Prepare a sample, and acquire the morphology of the thread groove of the high-precision lead screw to be processed by a laser confocal impact analyzer, including: the depth, width and angle of the thread groove;

[0023] Step 2.2: Perform phase modulation according to the morphology of the thread groove of the high-precision lead screw to be processed, so that the morphology of the processing laser beam is consistent with the morphology of the thread groove of the high-precision lead screw to be processed.

[0024] In one embodiment of the present invention, when entering the knife, the rod-shaped workpiece is first rotated and accelerated to a uniform speed, and then synchronously etched by a plurality of the processing laser beams; when exiting the knife, a plurality of the processing laser beams are first stopped, and then the rotation of the rod-shaped workpiece is decelerated to stop.

[0025] In one embodiment of the present invention, the distance between the entry position of the next etching line and the exit position of the previous etching line at the same end of the rod-shaped workpiece is ΔY; the length of ΔY is greater than or equal to 80% of the spot diameter of the processing laser beam.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The high-precision lead screw thread laser processing device of the present invention uses a modulated processing laser beam to process multiple threads, and splits the laser light source according to the number of multiple threads. The split processing laser beam has the same processing capability, and when acting on the material, the etching capability is consistent, so that the etching morphology of each thread is less different, thereby improving the processing accuracy. Compared with machining threads one by one by mechanical machining, the threads processed by laser beam splitting are more consistent, and the quality of each thread is similar. Also, due to synchronous machining, the processing efficiency is multiplied. In addition, based on the characteristics of the laser beam, the light knife formed by the processing laser beam will not be worn due to contact with the material, further improving the processing accuracy.

[0028] The present invention adopts a femtosecond laser. During the processing, high-energy and high-intensity laser is used to make atoms or molecules in the material lose electrons, thereby forming ions, and subtractive processing is achieved through ionization. Different from the thermal processing method of melting or vaporization used in the prior art, the thermal impact generated by laser processing is also lower, and it is a non-contact processing, which will not change the material stress, helps to maintain the stability of the processed material, further improves the processing accuracy, and has a wide range of applicability in the selection of processed materials.

[0029] The present invention shapes the laser light source according to the morphology of the multi-start thread, so that the morphology of the processing laser beam is adapted to the morphology of the thread groove of the high-precision lead screw to be processed, thereby realizing the processing of threads with various different morphologies, without the need to use customized tools and processing equipment, thereby reducing the processing cost and difficulty; at the same time, there is no need to change tools during the processing process, thereby improving the processing accuracy and efficiency of the high-precision lead screw thread.

[0030] The high-precision lead screw thread laser processing method of the present invention coordinates rotation, feeding and synchronous etching processing of several processing laser beams, realizes one-time forming of multiple threads, is friendly to mass production, has high production efficiency and low cost, and simultaneously improves production efficiency and processing accuracy.

[0031] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of a high-precision lead screw thread laser processing device provided by an embodiment of the present invention;

[0033] Figure 2 It is a flow chart of a high-precision lead screw thread laser processing method provided by an embodiment of the present invention;

[0034] Figure 3 The embodiment of the present invention provides Figure 2 Flowchart of step 2 in FIG.

[0035] Figures 4a to 4d It is a process flow chart of a high-precision lead screw thread laser processing method provided by an embodiment of the present invention;

[0036] Figure 5a to Figure 5c is a schematic diagram of a laser processing area provided by an embodiment of the present invention;

[0037] Figure 6 This is the topography of the ball screw thread under the camera;

[0038] Figure 7 This is the morphology of the ball screw thread under the confocal measuring instrument.

[0039] Icons: 10-laser; 20-optical transmission module; 30-rotation feeding module; 40-dust removal module; 50-gas auxiliary module; 100-rod-shaped workpiece. DETAILED DESCRIPTION

[0040] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, a high-precision lead screw thread laser processing device and processing method proposed in accordance with the present invention are described in detail below in combination with the accompanying drawings and specific implementation methods.

[0041] The above and other technical contents, features and effects of the present invention are clearly presented in the following detailed description of the specific implementation modes in conjunction with the accompanying drawings. Through the description of the specific implementation modes, the technical means and effects adopted by the present invention to achieve the predetermined purpose can be more deeply and specifically understood. However, the attached drawings are only for reference and explanation purposes and are not used to limit the technical solutions of the present invention.

[0042] Embodiment 1

[0043] Since the processing efficiency of multi-start threads is low, the processing cycle is long, and the consistency of the processing effect is poor, in view of this, this embodiment provides a high-precision screw thread laser processing device, such as Figure 1 As shown, Figure 1 It is a structural schematic diagram of a high-precision lead screw thread laser processing device provided in an embodiment of the present invention.

[0044] In this embodiment, a high-precision lead screw thread laser processing device includes: a laser 10, an optical path transmission module 20 and a rotation feeding module 30; wherein the laser 10 is used to output a laser light source; the optical path transmission module 20 is arranged behind the laser 10, and is used to split and shape the laser light source to obtain a plurality of processing laser beams; the plurality of processing laser beams are arranged at intervals along the circumferential direction, and the plurality of processing laser beams simultaneously etch the surface of a rod-shaped workpiece 100; the rotation feeding module 30 is used to clamp the rod-shaped workpiece 100, and drive the rod-shaped workpiece 100 to perform rotational motion and feed motion along the axial direction.

[0045] Exemplarily, the power of the laser 10 may be 50 W, the pulse width may be 200 fs, the wavelength may be 1030 nm, and a single pulse laser may be selected.

[0046] Preferably, the laser 10 is a femtosecond laser, and the laser 10 outputs a laser light source to achieve subtractive processing through ionization.

[0047] Exemplarily, the optical path transmission module 20 is used to transmit the light path, and after beam splitting and shaping, the focal points of several processing laser beams are focused on the surface of the rod-shaped workpiece 100; during use, the optical elements therein need to be kept clean and tidy to avoid energy loss caused by the light beam during transmission.

[0048] It is worth noting that the use of femtosecond lasers, through high-energy and high-intensity lasers during the processing process, causes the atoms or molecules in the material to lose electrons, thereby forming ions, and achieving subtractive processing through ionization. Different from the melting or vaporization thermal processing methods used in the prior art, the heat impact generated by laser processing is also lower, and it is a non-contact processing that will not change the material stress. The light knife itself will not wear due to contact with the material, which helps to maintain the stability of the processed material and further improves the processing accuracy. It also has a wide range of applicability in the selection of processed materials.

[0049] In an optional embodiment, a plurality of processing laser beams are arranged at equal intervals, and each processing laser beam is parallel to the surface normal direction of the rod-shaped workpiece 100 .

[0050] It is worth noting that the morphology of each processing laser beam is consistent with the morphology of the thread groove of the high-precision screw to be processed. By shaping the laser light source according to the morphology of the multi-thread, the morphology of the processing laser beam is adapted to the morphology of the thread groove of the high-precision screw to be processed, and various threads with different morphologies can be processed without the need for customized tools and processing equipment, reducing processing costs and processing difficulties; at the same time, there is no need to change tools during the processing process, which improves the processing accuracy and efficiency of high-precision screw threads.

[0051] Furthermore, when the number of thread starts of the high-precision lead screw to be processed is n, the laser light source is equally spaced into n strips with an equal division angle θ of 360 / n. The energy densities of several processing laser beams formed by the equally divided laser light source are the same. When several processing laser beams act on the rod at the same time, the processed area has the same quality and morphology. Compared with processing the threads one by one, the processing efficiency of processing n threads at the same time will be increased by n times. For example, it used to take 3 hours to process a 3-start thread, but it only takes 1 hour to process 3 threads at the same time, and the efficiency is increased to 3 times.

[0052] In addition, according to processing requirements, the spacing distance between several processing laser beams can also be set, that is, the several processing laser beams can be equally spaced, or the beams can be split in a manner of gradually increasing the spacing distance according to the law of thread processing.

[0053] In an optional embodiment, the rotating feed module 30 includes: a clamping chuck and a multi-axis rotating platform; wherein the clamping chuck is arranged on the multi-axis rotating platform for clamping the rod-shaped workpiece 100; the multi-axis rotating platform includes at least two rotating axes for driving the rod-shaped workpiece 100 to perform rotational motion and feeding motion along the axial direction.

[0054] Exemplarily, the rod-shaped workpiece 100 is clamped on a clamping chuck, and the clamping chuck and the rod-shaped workpiece 100 are coaxial and concentric.

[0055] For example, the multi-axis rotating platform can use an AC rotating axis platform, wherein the A axis (or B axis) can rotate within a range of ±120°; the C axis can rotate within a range of n×360°, the worktable diameter is greater than or equal to 200mm, and the load-bearing capacity is greater than or equal to 10KG. The A axis and C axis of the multi-axis rotating platform form a compound motion, and the travel along the X axis, Y axis, and Z axis is 800mm*500mm*500mm respectively.

[0056] The principle is that the rod-shaped workpiece 100 is clamped and fixed by a clamping chuck and can rotate with the multi-axis rotating platform. The rod-shaped workpiece 100 remains stable in the X-axis direction, feeds in the Y-axis direction, and rotates around the Y-axis.

[0057] In an optional embodiment, the high-precision lead screw thread laser processing device also includes: a dust removal module 40 and an air path auxiliary module 50; wherein the dust removal module 40 is used for adsorption and dust removal; the air path auxiliary module 50 is used for auxiliary blowing to remove the plasma generated by the laser etching process.

[0058] It is worth noting that during the laser processing, the high-power density laser couples energy to the workpiece surface very quickly, causing material ionization. When the laser beam penetrates the material, some particles are discharged from the holes in the penetrated material, which can easily cause contamination of some precision parts on the equipment. At the same time, it will also have an adverse effect on the health of the operator. Therefore, by setting up a dust removal module 40, it is kept open during the processing to continuously remove dust, thereby improving safety and reliability.

[0059] Exemplarily, the gas circuit auxiliary module 50 mainly includes pneumatic components such as gas source purification, pressure control, direction control, and flow control, which assist in blowing during processing and play a role in removing the plasma generated by the laser on the surface of the material.

[0060] For example, the gas used for the auxiliary blowing may be an inert gas or air.

[0061] It is worth noting that the auxiliary air blowing needs to cover the entire process of laser processing. Therefore, before the laser 10 emits light, the air path auxiliary module 50 needs to be turned on to start the air blowing, and then the air blowing needs to be turned off after the laser 10 finishes processing and emits light.

[0062] The working principle of a high-precision screw thread laser processing device of this embodiment is that the laser 10 outputs a laser light source, which is split and shaped in the optical path transmission module 20, and a light knife is formed by shaping. The morphology of the light knife is consistent with the morphology of the thread groove of the high-precision screw; specifically, the morphology of the light knife formed by shaping is consistent with the cross-sectional morphology of the processed thread, so as to replace the traditional props. After the laser light source is split, it can be regarded as forming a number of light knives. The several processing laser beams are arranged at equal intervals and act on the surface of the rod-shaped workpiece 100 at the same time, and cooperate with the multi-axis rotating platform to perform rotation and feed motion, so as to realize multi-angle simultaneous processing and simultaneous and effective etching of multiple threads.

[0063] It is worth noting that, due to the use of a processing laser beam for processing, the shaped processing laser beam and the rod-shaped workpiece 100 present a mutually coordinated processing mode, and the processing of a specific morphology thread is completed through a non-contact rotary feed processing method. This processing method abandons the problems of tool wear and processing stress that may be caused by traditional contact processing. With the energy effect of the shaped light and the rotary feed motion of the rod-shaped workpiece 100, the two work together to accurately shape a specific morphology thread that meets the design requirements on the surface of the rod, and it is suitable for processing rods of various different materials, fully demonstrating its wide applicability and providing an innovative and highly practical solution for high-precision thread processing.

[0064] The high-precision lead screw thread laser processing device of the present invention uses a modulated processing laser beam to process multiple threads, and splits the laser light source according to the number of multiple threads. The split processing laser beam has the same processing capability, and when acting on the material, the etching capability is consistent, so that the etching morphology of each thread is less different, thereby improving the processing accuracy. Compared with machining threads one by one by mechanical machining, the threads processed by laser beam splitting are more consistent, and the quality of each thread is similar. Also, due to synchronous machining, the processing efficiency is multiplied. In addition, based on the characteristics of the laser beam, the light knife formed by the processing laser beam will not be worn due to contact with the material, further improving the processing accuracy.

[0065] Embodiment 2

[0066] like Figure 2 As shown, this embodiment provides a high-precision screw thread laser processing method, including:

[0067] Step 1: Split the laser light source into several processing laser beams according to the number of thread starts of the high-precision lead screw to be processed.

[0068] Specifically, when the number of threads of the high-precision lead screw to be processed is n, the laser light source can be equally divided into n threads at equal distances, and the angle of division θ is 360 / n. The several processing laser beams formed by the equally divided laser light source have the same processing ability. When acting on the material, their etching ability is consistent, so that the etching morphology of each thread is slightly different. Compared with machining threads one by one by mechanical processing, the threads processed by laser beam splitting are more consistent, and the quality of each thread is similar.

[0069] Step 2: Adjust the shape of the processing laser beam according to the shape of the thread groove of the high-precision lead screw to be processed.

[0070] like Figure 3 As shown, Figure 3 The embodiment of the present invention provides Figure 2 Flowchart for step 2 in .

[0071] In an optional embodiment, step 2 includes:

[0072] Step 2.1: Prepare a sample and acquire the morphology of the thread groove of the high-precision lead screw to be processed by using a laser confocal impact analyzer, including: the depth, width and angle of the thread groove;

[0073] Step 2.2: According to the morphology of the thread groove of the high-precision lead screw to be processed, phase modulation is performed so that the morphology of the processing laser beam is consistent with the morphology of the thread groove of the high-precision lead screw to be processed.

[0074] Take the processing of a ball screw as an example. Figure 6 and Figure 7 As shown, Figure 6 This is the topography of the ball screw thread under the camera; Figure 7 This is the morphology of the ball screw thread under the confocal measuring instrument.

[0075] For example, since the morphologies of different thread grooves are different, the corresponding morphologies of the light knives formed by shaping should also be different. Therefore, before starting processing, a sample can be prepared first, and then the morphology of the thread groove of the high-precision screw to be processed can be acquired through a laser confocal impact analyzer, including: the depth, width and angle of the thread groove, so as to clarify the shape characteristics of the cross-section, and the thread groove data is measured by camera imaging, and then the internal contour cross-section view is analyzed based on this. Finally, the required spot shape is determined according to the cross-section view for feedback adjustment, and a phase modulator is used for phase modulation to control the energy density of the processing laser beam in the cross-section. The spot shape is detected by a beam quality analyzer, and finally a spot shape that meets the target thread is modulated, so that the thread morphology and the processing laser beam morphology correspond one to one, and then threads with different morphologies can be shaped.

[0076] It should be noted that the settings and operation processes of the laser confocal impact analyzer, phase modulation, and beam quality analyzer can all be implemented by referring to relevant existing technologies, and are not limited in this embodiment.

[0077] Step 3: Position and adjust the rod-shaped workpiece and clamp it.

[0078] Specifically, the rod-shaped workpiece is first fixed to the center of the rotating shaft of the clamping chuck, and coaxial positioning and concentric positioning are performed respectively; when performing coaxial positioning, the rod-shaped workpiece is rotated one circle, and the difference is measured with a micrometer or a dial indicator, and the error is controlled within 0.02mm; after confirming the coaxiality, concentric positioning is performed, the rod-shaped workpiece is placed vertically under the laser etching area, and a vertical line is etched along the Y-axis direction. The workpiece is rotated 180° and a vertical line parallel to the Y-axis direction is etched, and the two vertical lines are overlapped by moving the X-axis, and the current X-axis coordinate position is recorded to complete the concentric positioning.

[0079] It should be noted that the X-axis, Y-axis and Z-axis are all coordinate axes in a plane rectangular coordinate system and can be set according to actual processing needs, wherein the X-axis, Y-axis and Z-axis are perpendicular to each other.

[0080] Processing process such as Figures 4a to 4d and Figure 5a to Figure 5c As shown, Figures 4a to 4d It is a process flow chart of a high-precision lead screw thread laser processing method provided by an embodiment of the present invention; Figure 5a to Figure 5c Schematic diagram of the laser processing area provided by an embodiment of the present invention.

[0081] Step 4: Rotate the rod-shaped workpiece and perform etching processing synchronously by using a plurality of processing laser beams, enter the workpiece from the first end of the rod-shaped workpiece in the axial direction and feed the workpiece to the second end at a uniform speed to complete the etching processing of the first etching line of the first processing layer;

[0082] Step 5: Rotate the rod-shaped workpiece in the opposite direction, and perform etching processing synchronously by using a plurality of processing laser beams, wherein the cutting tool is inserted from the second end of the rod-shaped workpiece in the axial direction and fed to the first end at a uniform speed to exit the cutting tool, thereby completing the etching processing of the second etching line of the first processing layer;

[0083] It can be understood that the angular velocity ω can be set according to the actual processing accuracy and processing speed, while the linear velocity v is related to the pitch of the thread and the actual processing accuracy requirement.

[0084] Step 6: Repeat steps 3 and 4 until the etching process of the first processing layer is completed;

[0085] Step 7: lowering the focal plane of the processing laser beam several times along the surface normal direction of the rod-shaped workpiece, and repeating steps 4 to 6 until the etching process of the next processing layer is completed;

[0086] Step 8: Repeat step 7 until the etching process of the entire morphology of the thread groove of the high-precision lead screw to be processed is completed.

[0087] In an optional embodiment, when entering the knife, the rod-shaped workpiece is first rotated and accelerated to a uniform speed, and then synchronously etched by a plurality of processing laser beams; when exiting the knife, a plurality of processing laser beams are first stopped, and then the rotation of the rod-shaped workpiece is decelerated to a stop.

[0088] Specifically, the working mode of the rotating axis of the rod-shaped workpiece is as follows: Figure 4a As shown, the angular velocity ω is maintained, and the knife is fed from the first end A0 of the rod-shaped workpiece along the Y-axis direction at a uniform speed of linear velocity v to B0 to complete the etching process of the first etching line of the first processing layer. When the knife is fed from B1, there is a situation where the knife is pulled out and then re-entered, and the rotation of the rod-shaped workpiece also undergoes a process of gradually slowing down and stopping, and then accelerating in the reverse direction. During this period, the laser remains in the off state, and processing is performed after it stabilizes and runs to a uniform speed state.

[0089] The second etching line is processed from the starting point B1 to the end point A1 (line speed v', rotation speed ω'), until A n Processed to B n The first layer of thread topography is completed at Figure 4b As shown in , the processing focus of the first processing layer is Z0. After completing the processing of one layer, the focus drops ΔZ to point Z1, as shown in Figure 4d As shown, the second processing layer is processed, and the movement mode is the same as the first layer. After multiple processing, the depth is reduced to Z n points to meet the processing morphology requirements.

[0090] In an optional embodiment, the distance between the entry position of the next etching line and the exit position of the previous etching line at the same end of the rod-shaped workpiece is ΔY, such as Figure 4c As shown; the length of ΔY is greater than or equal to 80% of the spot diameter of the processing laser beam.

[0091] Specifically, Figure 4c and Figure 5a As shown in the figure, due to the influence of the spot diameter of the laser focus, the starting point of the second etching line needs to be moved inward by ΔY to B1, where ΔY ≥ spot diameter × 80%, that is, the length of ΔY must account for more than 80% of the spot diameter ratio. At this time, the overlap rate of the spots is more than 80%, achieving a continuous and uniform spot distribution, so that the etching surface is etched evenly. The reason for adjusting the starting point is that since the light beam will propagate forward in a straight line and repeatedly etch at the same position, the actual processing morphology will deviate from the expected morphology, that is, as shown in 5b, a repeated processing area will appear. In order to ensure the continuity of the processing morphology and the consistency of the processing, in the subsequent processing process, from A0 to A n , from B0 to Bn All displacements ΔY should be kept consistent, such as Figure 4b and 5c shown.

[0092] The working principle of the high-precision lead screw thread laser processing method implemented in this embodiment is that after turning on the dust removal module, the rotating rod-shaped workpiece is first rotated at a uniform speed for 2 to 3 circles to keep the angular velocity ω stable, the air path auxiliary module is turned on, and then the laser is turned on. At the same time, the tool is fed from the first end A0 of the rod-shaped workpiece along the Y-axis direction at a uniform speed of linear velocity v. After processing to the second end B0, the laser is turned off while the feed stops to complete the etching processing of the first etching line of the first processing layer.

[0093] Close the gas circuit auxiliary module, gradually reduce the angular velocity ω of the rod-shaped workpiece to 0, and then rotate the rod-shaped workpiece in the opposite direction, and rotate it at a uniform speed for 2 to 3 circles to keep the angular velocity ω′ stable, and feed the entry position ΔY; open the gas circuit auxiliary module, turn on the laser, enter the tool from the second end B1 of the rod-shaped workpiece, feed at a uniform speed of linear velocity v′, and reversely process to the first end A1 to exit the tool. Stop feeding and turn off the laser at the same time to complete the etching process of the second etching line of the first processing layer.

[0094] After a layer of morphology is processed in this way, the Z-axis focus drops from Z0 to the focal plane of point Z1, and the light knife morphology is not adjusted. The next layer of morphology is processed in sequence until the entire processing morphology is etched and the dust removal module is closed.

[0095] It is worth noting that each time the knife is inserted, it is first rotated at a uniform speed to achieve uniform motion, and then the feed motion is performed while the laser is being processed, so as to avoid uneven processing surface due to the axis not moving at a uniform speed when the knife is inserted. Similarly, each time the knife is removed, the laser is first turned off, and then the rotation is slowly decelerated and stopped. In addition, at the junction of each entry and exit of the knife, it is first rotated in one direction, and when the reverse processing is performed after completing the processing of an etching line, due to the acceleration and deceleration changes of the rotation, during this time interval, the laser needs to be kept off at all times, that is, to ensure the processing accuracy, the laser will only keep emitting light when the rod-shaped workpiece is in a uniform rotation state.

[0096] The high-precision lead screw thread laser processing method of the present invention coordinates rotation, feeding and synchronous etching processing of several processing laser beams, realizes one-time forming of multiple threads, is friendly to mass production, has high production efficiency and low cost, and simultaneously improves production efficiency and processing accuracy.

[0097] Embodiment 3

[0098] Exemplarily, the high-precision screw thread laser processing device of Example 1 and the high-precision screw thread laser processing method of Example 2 are used, and a single-pulse laser with a power of 50 W, a pulse width of 200 fs, and a wavelength of 1030 nm is used as a laser light source to process a ball screw with an inverted V-shaped three-start thread as an example for explanation.

[0099] The inverted V-shaped triple-start thread has a width of 0.66mm, a depth of 0.36mm, a groove angle of 85° to 95°, a lead of 2mm, and a pitch of 2 / 3mm.

[0100] First, turn on the dust removal module, rotate the B-axis of the multi-axis rotating platform to 90°, make the X-axis and Y-axis both in the horizontal plane, fix the rod-shaped workpiece and rotate it one circle, use the micrometer / verbial indicator to measure the difference to ensure that the error is controlled within 0.02mm; place the rod-shaped workpiece vertically under the laser etching area, etch a vertical line along the Y-axis direction, rotate the rod-shaped workpiece 180° and etch another vertical line along the Y-axis direction, move the X-axis to make the two vertical lines overlap, record the current X-axis coordinate position, and thus determine the positions of the X-axis, Y-axis, and Z-axis.

[0101] The rod-shaped workpiece is rotated around the Y axis for 3 circles, and the angular velocity of the workpiece is maintained at 0.6s / r. After the rotation is stable, the gas circuit auxiliary module is turned on, and then the laser is turned on. At the same time, the first end of the rod-shaped workpiece is fed along the Y axis at a uniform speed of 3.33mm / s. After processing to the second end, the laser is turned off synchronously when the feed stops, and the etching process of the first etching line of the first processing layer is completed. The gas circuit auxiliary module is turned off, and the angular velocity of the rod-shaped workpiece is gradually reduced to 0.

[0102] It rotates in the opposite direction at an angular speed of 0.6s / r. After rotating for 3 turns and stabilizing, the entry position is fed 0.8 spots with a width of 0.24mm. The gas path auxiliary module is turned on, and the laser is turned on. The tool is inserted from the second end of the rod-shaped workpiece, and the linear speed is fed at a uniform speed of 3.33mm / s. The tool is processed in the reverse direction to the first end and the tool is removed. When the feed stops, the laser is turned off synchronously to complete the etching process of the second etching line of the first processing layer.

[0103] After the cycle completes the processing of one layer of morphology, the total width of the first layer of morphology is 0.600mm, the Z axis drops 0.1mm in height, the total width of the second layer of morphology is 0.300mm, a total of 3 layers are dropped, and the processing width of the last layer is 0.001mm. The etching of the entire inverted V-shaped three-head thread processing morphology is completed. Finally, the dust removal module is closed and the processed rod-shaped workpiece is removed.

[0104] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant is intended to cover non-exclusive inclusion, so that the article or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the article or device including the elements. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The orientation or position relationship indicated by "up", "down", "left", "right", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0105] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A high-precision screw thread laser processing device, characterized in that: include: A laser (10), an optical path transmission module (20) and a rotation feeding module (30); Wherein, the laser (10) is used to output a laser light source; The optical transmission module (20) is arranged behind the laser (10) and is used to split and shape the laser light source to obtain a plurality of processing laser beams; the plurality of processing laser beams are arranged at intervals along the circumferential direction, and the plurality of processing laser beams simultaneously etch and process the surface of the rod-shaped workpiece (100); The rotary feeding module (30) is used to clamp the rod-shaped workpiece (100) and drive the rod-shaped workpiece (100) to perform rotational motion and feeding motion along an axial direction.

2. The high-precision screw thread laser processing device according to claim 1, characterized in that: The laser (10) is a femtosecond laser, and the laser light source output by the laser (10) realizes subtractive processing through ionization.

3. The high-precision screw thread laser processing device according to claim 1, characterized in that: A plurality of the processing laser beams are arranged at equal intervals, and each of the processing laser beams is parallel to the surface normal direction of the rod-shaped workpiece (100).

4. The high-precision screw thread laser processing device according to claim 1, characterized in that: The shape of each processing laser beam is consistent with the shape of the thread groove of the high-precision lead screw to be processed.

5. The high-precision screw thread laser processing device according to claim 1, characterized in that: The rotary feeding module (30) comprises: a clamping chuck and a multi-axis rotary platform; wherein the clamping chuck is arranged on the multi-axis rotary platform and is used to clamp the rod-shaped workpiece (100); The multi-axis rotating platform comprises at least two rotating axes, which are used to drive the rod-shaped workpiece (100) to perform rotational motion and feed motion along the axis direction.

6. The high-precision screw thread laser processing device according to claim 1, characterized in that: Also includes: A dust removal module (40) and an air path auxiliary module (50); wherein the dust removal module (40) is used for dust removal by adsorption; The gas circuit auxiliary module (50) is used to assist in blowing gas to remove plasma generated by laser etching processing.

7. A high-precision screw thread laser processing method, characterized in that: include: Step 1: Split the laser light source into several processing laser beams according to the number of thread heads of the high-precision lead screw to be processed; Step 2: adjusting the shape of the processing laser beam according to the shape of the thread groove of the high-precision lead screw to be processed; Step 3: Position and adjust the rod-shaped workpiece and clamp it; Step 4: rotating the rod-shaped workpiece, and performing synchronous etching processing with a plurality of the processing laser beams, wherein the cutting tool is inserted from the first end of the rod-shaped workpiece in the axial direction and fed to the second end at a uniform speed to exit the workpiece, thereby completing the etching processing of the first etching line of the first processing layer; Step 5: Rotate the rod-shaped workpiece in the opposite direction, and perform etching processing synchronously by using a plurality of processing laser beams, wherein the cutting tool is inserted from the second end of the rod-shaped workpiece in the axial direction and fed to the first end at a uniform speed to exit the workpiece, thereby completing the etching processing of the second etching line of the first processing layer; Step 6: Repeat steps 3 and 4 until the etching process of the first processing layer is completed; Step 7: lowering the focal plane of the processing laser beam several times along the surface normal direction of the rod-shaped workpiece, and repeating steps 4 to 6 until the etching process of the next processing layer is completed; Step 8: Repeat step 7 until the etching process of the entire morphology of the thread groove of the high-precision lead screw to be processed is completed.

8. The high-precision screw thread laser processing method according to claim 7, characterized in that: The step 2 comprises: Step 2.1: Prepare a sample, and acquire the morphology of the thread groove of the high-precision lead screw to be processed by a laser confocal impact analyzer, including: the depth, width and angle of the thread groove; Step 2.2: Perform phase modulation according to the morphology of the thread groove of the high-precision lead screw to be processed, so that the morphology of the processing laser beam is consistent with the morphology of the thread groove of the high-precision lead screw to be processed.

9. The high-precision screw thread laser processing method according to claim 7, characterized in that: When cutting, the rod-shaped workpiece is first rotated and accelerated to a uniform speed, and then etched synchronously by a plurality of the processing laser beams; When the knife is removed, a plurality of the processing laser beams are stopped first, and then the rotation of the rod-shaped workpiece is decelerated to stop.

10. The high-precision screw thread laser processing method according to claim 7, characterized in that: The distance between the entry position of the next etching line and the exit position of the previous etching line at the same end of the rod-shaped workpiece is ΔY; the length of ΔY is greater than or equal to 80% of the spot diameter of the processing laser beam.

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