A laser perforation machining method and numerical control system

Abstract

The present application relates to a kind of laser perforation processing method and numerical control system, the method is suitable for processing the plate of thickness above 60mm, method includes: in the operation interface of numerical control system input basic parameters for laser perforation;Numerical control system is initialized after, according to the basic parameters, control cutting head moves to reference position;Numerical control system sequentially carries out perforation processing operation to the plate to be processed according to the control parameters of first stage, second stage and third stage, to make the plate to be processed realize stable perforation;The basic parameters include: the control parameters of first stage, second stage and third stage, initial value and dynamic change equation, termination condition etc.;The first stage is static puncture stage, and the second stage and third stage are both dynamic puncture stage.The method of the present application breaks through the difficulty that super-thick plate cannot realize laser perforation, and also avoids the shortcomings of burst hole and overburning when laser perforation is carried out on super-thick plate.

Description

TECHNICAL FIELD

[0001] The present application relates to numerical control machining technology, and in particular to a laser perforation machining method and a numerical control system. BACKGROUND

[0002] With the rapid development of metal processing technology, laser processing method gradually replaces the conventional machining method with the advantages of high efficiency, high precision, low cost, etc. At present, it has been effectively witnessed in heavy industry, shipbuilding industry, metal container industry and military industry, but in the processing of super-thick plate in the shipbuilding industry, it encounters the bottleneck of being cuttable but not perforable, which leads to the fact that laser cutting cannot develop in the field of super-thick plate.

[0003] It is well known that in the field of laser cutting, the most widely used is thin plate high-speed and high-precision cutting, and 20mm-50mm medium-thick plate cutting, but it cannot be realized when processing 60mm-90mm super-thick plate. It is known that in order to ensure that the entire part is cut off, the perforation of the plate must be completed first, and a through hole is realized at the perforation position, so that the light beam can completely pass through the plate, thereby meeting the starting requirement of laser cutting. When the plate is too thick, it is easy to appear that the perforation cannot penetrate, the slag accumulation is too thick, and the hole explosion phenomenon occurs, which leads to the fact that the super-thick plate cannot be cut, and the processing of the super-thick plate becomes a blind area in the field of laser cutting. In recent years, with the gradual increase of the upper limit of laser power, the laser cutting of super-thick plate has become a big problem in the field of laser cutting, and has also attracted the attention of the metal processing industry.

[0004] The various laser perforation methods in the prior art cannot realize the perforation of super-thick plate, that is, the super-thick plate cannot be penetrated, the slag accumulation is too thick, or the hole explosion phenomenon occurs easily due to high duty cycle, the plate is heated, and the perforation effect is unstable. SUMMARY

[0005] (I) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present application provides a laser perforation machining method for super-thick plate, thereby breaking through the difficulty that the super-thick plate cannot realize laser perforation, and avoiding the defects of hole explosion and overburning when laser perforation is performed on the super-thick plate.

[0007] (II) Technical solutions

[0008] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the present application include:

[0009] In a first aspect, the present application provides a laser perforation machining method, which is suitable for processing plate with a thickness of 60mm or more, and the method comprises the following steps:

[0010] S10, inputting basic parameters for laser perforation on an operation interface of a numerical control system;

[0011] S20, after initialization, the numerical control system controls the cutting head to move to a reference position according to the basic parameters;

[0012] S30, the numerical control system sequentially performs perforation processing operation on the plate to be processed according to the control parameters of the first stage, the second stage and the third stage, so that the plate to be processed realizes stable perforation;

[0013] The basic parameters include:

[0014] The perforation time period of the first stage, the second stage and the third stage;

[0015] The control parameters of the cutting head in the first stage;

[0016] The initial value and the dynamic change equation of the control parameters of the cutting head in the second stage and the third stage;

[0017] The termination condition of the first stage, the termination condition of the second stage and the termination condition of the third stage;

[0018] The first stage is a static puncture stage, and the second stage and the third stage are dynamic puncture stages.

[0019] Optionally, in the S10,

[0020] The perforation time period of the first stage is t1;

[0021] The perforation time period of the second stage is t2;

[0022] The perforation time period of the third stage is t3;

[0023] The control parameters of the cutting head in the first stage include: perforation height, perforation frequency, perforation duty cycle, perforation power, perforation focal point;

[0024] The dynamic change equation of the perforation duty cycle, the perforation frequency and the perforation focal point in the second stage, the initial value of the perforation duty cycle, the perforation frequency and the perforation focal point;

[0025] The dynamic change equation of the perforation duty cycle, the perforation frequency and the perforation focal point in the third stage, the initial value of the perforation duty cycle, the perforation frequency and the perforation focal point.

[0026] Optionally, the initial value of the perforation duty cycle in the second stage is lower than the value of the perforation duty cycle in the first stage, and the termination value of the perforation duty cycle is higher than the initial value of the perforation duty cycle in the second stage;

[0027] The initial value and the terminal value of the second stage perforation frequency are lower than the values of the first stage perforation frequency; that is, the initial value of the second stage perforation frequency is lower than the initial value of the first stage perforation frequency, and the terminal value of the second stage perforation frequency is lower than the terminal value of the first stage perforation frequency;

[0028] The initial value and the terminal value of the second stage perforation power are equal to the values of the first stage perforation power; that is, the initial value of the second stage perforation power is equal to the initial value of the first stage perforation power, and the terminal value of the second stage perforation power is equal to the terminal value of the first stage perforation power;

[0029] The initial value of the second stage perforation focus is lower than the value of the first stage perforation focus, and the terminal value of the second stage perforation focus is lower than the initial value of the first stage perforation focus;

[0030] The initial value of the third stage perforation duty cycle is lower than the terminal value of the second stage perforation duty cycle, and the terminal value of the third stage perforation duty cycle is lower than the initial value of the third stage perforation duty cycle;

[0031] The initial value of the third stage perforation frequency is lower than the terminal value of the second stage perforation frequency, and the terminal value of the third stage perforation frequency is higher than the initial value of the third stage perforation frequency;

[0032] The initial value and the terminal value of the third stage perforation power are equal to the terminal value of the second stage perforation power;

[0033] The initial value of the third stage perforation focus is higher than the terminal value of the second stage perforation focus, and the terminal value of the third stage perforation focus is lower than the initial value of the third stage perforation focus.

[0034] Optionally, in the second stage and the third stage, the dynamic change equation of the perforation duty cycle and the perforation frequency is y=a+sin(t*Δf); t is a time variable, y is the perforation duty cycle value or the perforation frequency value corresponding to t, a is the initial value of the perforation duty cycle / the initial value of the perforation frequency, and Δf is the increment value corresponding to the perforation duty cycle / the increment value corresponding to the perforation frequency;

[0035] The dynamic change equation of the perforation focus is y'=kt; k is a known coefficient, and y' is the perforation focus value corresponding to t.

[0036] Optionally, the first stage perforation frequency is greater than or equal to 1000 Hz, the first stage perforation duty cycle is greater than or equal to 80%, and the first stage focus is greater than or equal to 5 mm;

[0037] The initial value of the first stage perforation height is 1 / 3 to 1 / 2 of the thickness of the plate to be processed;

[0038] The depth of the pit formed in the plate to be processed after the first stage of perforation is 1 / 4 to 1 / 3 of the thickness of the plate to be processed, and the width of the pit is 1 / 12 to 1 / 10 of the thickness of the plate to be processed.

[0039] Optionally, the second stage perforation duty cycle is between 40% and 60%, and the perforation focal point is between -10 mm and -17 mm.

[0040] The initial perforation focal point of the second stage is higher than the final perforation focal point of the second stage, and the dynamic change equation is y=kx.

[0041] The depth of the pit formed in the plate to be processed after the second stage of perforation is 3 / 2 to 3 / 4 of the thickness of the plate to be processed, and the aperture is 1 / 15 to 1 / 13 of the thickness of the plate to be processed.

[0042] And / or,

[0043] The third stage perforation frequency is between 20 Hz and 100 Hz, the perforation duty cycle is between 20% and 40%, and the perforation focal point is between -30 mm and -15 mm.

[0044] The initial value of the third stage perforation height is 1 / 10 to 1 / 9 of the thickness of the plate to be processed.

[0045] Optionally, the termination condition of the first stage is that the perforation time of the first stage reaches a first set value.

[0046] The termination condition of the second stage is that the perforation time of the second stage reaches a second set value.

[0047] The termination condition of the third stage is that the perforation time of the third stage reaches a third set value.

[0048] Optionally, the S30 comprises:

[0049] The numerical control system perforates according to the control parameters of the first stage, and when the perforation reaches the termination condition of the first stage, the numerical control system controls the cutting head to stop perforating and adjusts the control parameters of the cutting head to the initial value of the control parameters of the second stage.

[0050] The numerical control system perforates according to the control parameters of the second stage, and when the perforation reaches the termination condition of the second stage, the numerical control system controls the cutting head to stop perforating and adjusts the control parameters of the cutting head to the initial value of the control parameters of the third stage.

[0051] The numerical control system perforates according to the control parameters of the third stage, and when the plate to be processed is penetrated, the perforation is stopped according to the feedback information of the plate penetration feedback device.

[0052] In a second aspect, the embodiments of the present application also provide a numerical control system, comprising a memory for storing a computer program and a processor for executing the computer program stored in the memory and performing the steps of the laser perforation processing method in the numerical control system according to any one of the first aspect.

[0053] (III) Beneficial Effects

[0054] The method of the embodiments of the present application ensures perforation stability and avoids burst holes by changing the laser frequency, duty cycle and focal point in a phased and curvilinear and dynamic manner in real time during the perforation process, thereby breaking through the difficulty of laser perforation of ultra-thick plates and avoiding the defects of burst holes and overburning during laser perforation of ultra-thick plates.

[0055] The method of the present application is applied to ultra-thick plates, and different ways of high frequency, low frequency and point frequency are used for the remaining thickness to be perforated in the perforation process, and the difference of the trigonometric function is supplemented by changing the duty cycle and frequency, and the focal point is gradually changed, which improves the stability of the perforation and protects the perforation environment and avoids burst holes. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 A flowchart of the laser perforation processing method provided in the embodiments of the present application is shown in the figure;

[0057] Figure 2 A schematic diagram of the second stage perforation frequency dynamic curve in the embodiments of the present application is shown in the figure;

[0058] Figure 3 A schematic diagram of the second stage perforation duty cycle dynamic curve in the embodiments of the present application is shown in the figure;

[0059] Figure 4 A schematic diagram of the third stage perforation frequency dynamic curve in the embodiments of the present application is shown in the figure;

[0060] Figure 5 A schematic diagram of the third stage perforation duty cycle dynamic curve in the embodiments of the present application is shown in the figure. DETAILED DESCRIPTION

[0061] In order to better explain the present application and facilitate understanding, the present application will be described in detail in combination with the drawings and specific embodiments.

[0062] Based on the problems existing in the existing laser cutting technology, the method of the embodiments of the present application breaks through the upper limit of the laser perforation thickness and can realize ultra-thick plate perforation, no burst holes and no slag during perforation. The technical solutions of the present disclosure will be described in detail.

[0063] Embodiment One

[0064] As Figure 1 shown, the embodiment of the application provides a laser perforation processing method, the execution subject of the method of the embodiment can be an electronic device / control device carrying a numerical control system, and the specific method comprises the following steps:

[0065] S10, input basic parameters for laser perforation on an operation interface of the numerical control system.

[0066] For example, the basic parameters can include:

[0067] perforation time periods of the first stage, the second stage and the third stage;

[0068] control parameters of the cutting head in the first stage;

[0069] initial values and dynamic change equations of the control parameters of the cutting head in the second stage and the third stage;

[0070] termination conditions of the first stage, termination conditions of the second stage and termination conditions of the third stage;

[0071] The first stage is a static puncture stage, and the second stage and the third stage are dynamic puncture stages.

[0072] S20, after initialization, the numerical control system controls the cutting head to move to a reference position according to the basic parameters.

[0073] The reference position in this step can be the initial value of the perforation height of the cutting head in the basic parameters.

[0074] S30, the numerical control system sequentially performs perforation processing operations on the to-be-processed plate according to the control parameters of the first stage, the second stage and the third stage, so that the to-be-processed plate realizes stable perforation;

[0075] For example, the numerical control system performs perforation according to the control parameters of the first stage, and when the perforation reaches the termination condition of the first stage, the numerical control system controls the cutting head to stop perforation and adjusts the control parameters of the cutting head to the initial value of the control parameters of the second stage.

[0076] The numerical control system performs perforation according to the control parameters of the second stage, and when the perforation reaches the termination condition of the second stage, the numerical control system controls the cutting head to stop perforation and adjusts the control parameters of the cutting head to the initial value of the control parameters of the third stage.

[0077] The numerical control system performs perforation according to the control parameters of the third stage, and when the to-be-processed plate is perforated, the perforation is stopped according to the feedback information of the plate perforation feedback device.

[0078] The method of the embodiment changes the laser frequency, duty cycle and focal point in a phased and curvilinear and dynamic manner in real time during the piercing process, ensures piercing stability and avoids burst holes, breaks through the problem that laser piercing cannot be realized on super-thick plates, and also avoids the defects of burst holes and overburning when laser piercing is performed on super-thick plates.

[0079] To better understand the above basic parameters, the basic parameters are described in detail below.

[0080] In the embodiment, the piercing time period of the first stage is t1; the piercing time period of the second stage is t2; and the piercing time period of the third stage is t3.

[0081] The control parameters of the cutting head in the first stage include: piercing height, piercing frequency, piercing duty cycle, piercing power and piercing focal point.

[0082] The dynamic change equation of the piercing duty cycle, the piercing frequency and the piercing focal point in the second stage, the initial values of the piercing duty cycle, the piercing frequency and the piercing focal point, and the dynamic change equation of the focal point (which can be the piercing focal point).

[0083] The dynamic change equation of the piercing duty cycle, the piercing frequency and the piercing focal point in the third stage, the initial values of the piercing duty cycle, the piercing frequency and the piercing focal point, and the dynamic change equation of the focal point (which can be the piercing focal point).

[0084] For the second stage and the third stage,

[0085] The initial value of the piercing duty cycle in the second stage is lower than the value of the piercing duty cycle in the first stage, and the terminal value of the piercing duty cycle in the second stage is higher than the initial value of the piercing duty cycle in the second stage.

[0086] The initial value and the terminal value of the piercing frequency in the second stage are both lower than the value of the piercing frequency in the first stage; that is, the initial value of the piercing frequency in the second stage is lower than the initial value of the piercing frequency in the first stage, and the terminal value of the piercing frequency in the second stage is lower than the terminal value of the piercing frequency in the first stage.

[0087] The initial value and the terminal value of the piercing power in the second stage are both equal to the value of the piercing power in the first stage; that is, the initial value of the piercing power in the second stage is equal to the initial value of the piercing power in the first stage, and the terminal value of the piercing power in the second stage is equal to the terminal value of the piercing power in the first stage.

[0088] The initial value of the piercing focal point in the second stage is lower than the initial value of the piercing focal point in the first stage, and the terminal value of the piercing focal point in the second stage is lower than the initial value of the piercing focal point in the second stage.

[0089] The initial value of the third-stage perforation duty cycle is lower than the terminal value of the second-stage perforation duty cycle, and the terminal value of the third-stage perforation duty cycle is lower than the initial value of the third-stage perforation duty cycle;

[0090] The initial value of the third-stage perforation frequency is lower than the terminal value of the second-stage perforation frequency, and the terminal value of the third-stage perforation frequency is higher than the initial value of the third-stage perforation frequency;

[0091] The initial value and the terminal value of the third-stage perforation power are both equal to the terminal value of the second-stage perforation power;

[0092] The initial value of the third-stage perforation focus is higher than the terminal value of the second-stage perforation focus, and the terminal value of the perforation focus is lower than the initial value of the third-stage perforation focus.

[0093] In the second stage and the third stage, the dynamic change equation of the perforation duty cycle and the perforation frequency is y=a+sin(t*Δf); t is a time variable, y is the perforation duty cycle value or the perforation frequency value corresponding to t, a is the initial value of the perforation duty cycle / the initial value of the perforation frequency, and Δf is the incremental value corresponding to the perforation duty cycle / the incremental value corresponding to the perforation frequency;

[0094] The dynamic change equation of the perforation focus is y'=kt; k is a known coefficient, and y' is the perforation focus value corresponding to t.

[0095] The first-stage perforation frequency is greater than or equal to 1000 Hz, the first-stage perforation duty cycle is greater than or equal to 80%, and the first-stage focus is greater than or equal to 5 mm;

[0096] The initial value of the first-stage perforation height is 1 / 3 to 1 / 2 of the thickness of the plate to be processed;

[0097] After the first-stage perforation is completed, the depth of the pit formed in the plate to be processed is 1 / 4 to 1 / 3 of the thickness of the plate to be processed, and the width of the pit is 1 / 12 to 1 / 10 of the thickness of the plate to be processed.

[0098] The second-stage perforation duty cycle is between 40% and 60%, and the perforation focus is between -10 mm and -17 mm,

[0099] The initial perforation focus of the second stage is higher than the terminal perforation focus of the second stage, and the dynamic change equation is y=kx;

[0100] After the second-stage perforation is completed, the depth of the pit formed in the plate to be processed is 3 / 2 to 3 / 4 of the thickness of the plate to be processed, and the aperture is 1 / 15 to 1 / 13 of the thickness of the plate to be processed;

[0101] and / or,

[0102] The third stage perforation frequency is between 20 Hz and 100 Hz, the perforation duty cycle is between 20% and 40%, and the perforation focal point is between -30 mm and -15 mm.

[0103] The initial value of the perforation height in the third stage is 1 / 10 to 1 / 9 of the thickness of the plate to be processed.

[0104] The termination condition of the first stage is that the perforation time of the first stage reaches a first set value.

[0105] The termination condition of the second stage is that the perforation time of the second stage reaches a second set value.

[0106] The termination condition of the third stage is that the perforation time of the third stage reaches a third set value.

[0107] In addition, the above-mentioned positive defocus is that the focal point value is positive, and the negative defocus is that the focal point value is negative.

[0108] Therefore, by changing the laser frequency, duty cycle, and focal point in a phased and curvilinear and dynamic manner in real time during the perforation process, the perforation stability is ensured, and the problem of burst hole is avoided, which breaks through the difficulty of laser perforation of ultra-thick plates, and also avoids the shortcomings of burst hole and overburning during laser perforation of ultra-thick plates.

[0109] Example Two

[0110] The execution subject of the method of the present embodiment is a numerical control system, which has an operation interface, and a user can input control parameters and dynamic change equations of each stage based on the operation interface. In combination with the above-mentioned perforation process, the numerical control system can control the perforation process of the ultra-thick plate. Figures 2 to 5 The method is described below.

[0111] The laser perforation processing method for the ultra-thick plate in the present embodiment can include the following steps:

[0112] 201. Set the perforation parameters in different perforation states of each stage on the operation interface of the numerical control system.

[0113] In the present embodiment, the first position of the cutting head after initialization is set as the perforation height (such as a height h) of the first stage, the perforation parameters are set, and the perforation process is set to be completed within the total time T (T=t1+t2+t3). The perforation parameters set at this time are the first stage perforation parameters, which include perforation time, frequency, duty cycle, power, and focal point parameters, and the focal point value of the first stage is set as positive defocus.

[0114] The distance of the cutting head to the surface of the ultra-thick plate is the perforation height, and the perforation parameters in the first stage are static and do not change, and static piercing is performed according to these parameters.

[0115] 202、the numerical control system performs the piercing according to the control parameters of the first stage, and when the piercing reaches the termination condition of the first stage, the numerical control system controls the cutting head to stop the piercing and adjusts the control parameters of the cutting head to the initial values of the control parameters of the second stage;

[0116] After the first stage of piercing is completed, the cutting head is moved from the first stage piercing height to the second stage piercing height, and the second stage of piercing is performed on the super-thick plate according to the second stage piercing parameters, and the initial value and the termination value of the focus in the second stage piercing parameters are both negative defocus.

[0117] During the second stage piercing time, the piercing frequency is from medium to low, the piercing duty cycle is from low to medium, and the piercing focus gradually moves negatively, wherein the change rates of the focus, the frequency and the duty cycle are different.

[0118] 203、the numerical control system performs the piercing according to the control parameters of the second stage, and when the piercing reaches the termination condition of the second stage, the numerical control system controls the cutting head to stop the piercing and adjusts the control parameters of the cutting head to the initial values of the control parameters of the third stage;

[0119] That is, after the second stage of piercing is completed, the cutting head is moved from the second stage piercing height to the third stage piercing height, and the third stage of piercing is performed on the super-thick plate according to the third stage piercing parameters, and the initial value and the termination value of the focus in the third stage piercing parameters are both negative defocus, and during the third stage piercing time, wherein the piercing frequency is from ultra-low to low, the piercing duty cycle is from low to ultra-low, and the piercing focus gradually moves negatively, wherein the change rates of the focus, the frequency and the duty cycle are different.

[0120] 204、the numerical control system performs the piercing according to the control parameters of the third stage, and when the plate to be processed is penetrated, the piercing is stopped according to the feedback information of the plate penetration feedback device.

[0121] In the embodiment, the perforating process is divided into three stages, the last two stages adopt dynamic curve frequency conversion, dynamic curve duty cycle variation and linear dynamic zooming, the initial value and the terminal value of the duty cycle in the first stage perforating parameters are greater than the initial value and the terminal value of the duty cycle in the second stage and the third stage perforating parameters, the frequency in the first stage perforating parameters is greater than the initial value and the terminal value of the frequency in the second stage and the third stage perforating parameters, wherein the first stage perforating frequency F1 is not less than 1000 Hz (preferably 1000 Hz), the first stage duty cycle D1 is not less than 80% (for example, 80%), the first stage focus value f1 is not less than +5 mm (for example, +5 mm), the second stage frequency initial value F2 is not higher than 400 Hz (for example, 400 Hz), the second stage frequency terminal value F2' is not less than 200 Hz (for example, 200 Hz), the second stage duty cycle initial value D2 is not less than 40% (for example, 40%), the second stage duty cycle terminal value D2' is not higher than 60% (for example, 60%), the second stage focus initial value f2 is not greater than-10 mm (for example, -10 mm), the second stage focus terminal value f2' is not less than-17 mm (for example, -17 mm), wherein the third stage frequency initial value F3 is not less than 20 Hz (for example, 20 Hz), the third stage frequency terminal value F3' is not higher than 100 Hz (for example, 100 Hz), the third stage duty cycle initial value D3 is not higher than 40% (for example, 40%), the third stage duty cycle terminal value D3' is not less than 20% (for example, 20%), the third stage focus initial value f3 is not higher than-15 mm (for example, -15 mm), the third stage focus terminal value f3' is not less than-25 mm (for example, -25 mm), wherein the perforating time of the three stages is respectively t1, t2 and t3, and the total time T=t1+t2+t3.

[0122] The state of the duty cycle and the frequency in the embodiment can be divided into three kinds, the first kind is static high duty cycle, high frequency and positive focus, the second kind is low duty cycle to high duty cycle with medium frequency to low frequency curve and linear negative defocus dynamic change, and the third kind is low duty cycle to ultra-low duty cycle with ultra-low frequency to low frequency curve and linear negative defocus dynamic change, which realizes the perforation of the super-thick plate, and the specific implementation is as follows:

[0123] (1) Static high duty cycle, high frequency and positive defocus

[0124] In the perforating process, A1) the frequency in the first stage (i.e. time t1) is set to 1000 Hz, the duty cycle is set to 80%, and the focus is set to +5 mm, and the plate is perforated statically.

[0125] (2) Low duty cycle to medium duty cycle with medium frequency to low frequency and linear negative defocusing dynamic change

[0126] During the drilling process, A2) in the second stage of drilling, the change of duty cycle: the duty cycle of the laser beam is set to 40% at the beginning of the second stage (i.e. time t2) and 60% at the end, and the real-time duty cycle value during time t2 is: where Δt is the time consumed after the start of the second stage drilling, t2 is the set time period; d(t) is the output duty cycle value at a certain time in the second stage;

[0127] The frequency of the laser beam is set to 400 Hz at the beginning of the second stage and 200 Hz at the end, and the real-time frequency value during time period t2 is: t2 is the set time period;

[0128] The focal point of the laser beam is set to -10 mm at the beginning of the second stage and -17 mm at the end, and the real-time focal point is: t2 is the set time period;

[0129] In the above formulas, the parameters are as follows:

[0130] d(t) is the output duty cycle value at a certain time in the second stage, D2' is the set end duty cycle value in the second stage, D2 is the set start duty cycle value in the second stage, t2 is the set drilling time in the second stage, F(t) is the output frequency value at a certain time in the second stage, F2' is the set end frequency value in the second stage, F2 is the set start frequency value in the second stage, t2 is the set drilling time in the second stage, and t is the drilling time consumed from the start of the second stage to the current time.

[0131] During the drilling process in the second stage, the duty cycle increases in a sinusoidal function curve with an acceleration of d'(t)% / ms 2 , the frequency decreases in a sinusoidal function curve with an acceleration of F'(t) Hz / ms 2 , and the focal point decreases linearly with an acceleration of f'(t) mm / ms 2 .

[0132] Table 1 is the data for low duty cycle to high duty cycle with medium frequency to low frequency and linear negative defocusing dynamic change:

[0133]

[0134] Based on the above, in the second stage of the perforation process, by complementary state of laser beam duty cycle and beam frequency at different times, the problem of excessive accumulation of slag during the perforation process can be solved, and at different acceleration states, the problem of burst hole caused by excessive accumulated energy per unit time can be prevented. With the gradual downward movement of the focal point with the increase of the perforation time, the perforation depth is sufficient and stable.

[0135] (3) Low duty cycle to ultra-low duty cycle with ultra-low frequency to low frequency and linear negative defocusing dynamic change;

[0136] During the perforation process, A3) In the third stage of perforation, the change of duty cycle: the initial value of the duty cycle of the laser beam in the third stage (i.e. time t3) is set to 40%, and the terminal value is set to 20%, and the real-time duty cycle value in time t3 is: Where Δt is the time consumed after the start of the third stage of perforation, the frequency of the laser beam in the third stage is set to 20Hz at the initial value, and set to 100Hz at the terminal value, and the real-time frequency value in time t3 is: The focal point of the laser beam is set to -15mm at the initial value in the third stage, and set to -25mm at the terminal value, and the real-time focal point is: During the third stage of perforation, the duty cycle decreases with a sinusoidal function curve with an acceleration of d'(t) % / ms 2 The frequency increases with a sinusoidal function curve with an acceleration of F'(t) Hz / ms 2 The focal point decreases linearly with an acceleration of f'(t) mm / ms 2 .

[0137] d(t) is the output duty cycle value at a certain time in the third stage, D3' is the set terminal duty cycle value in the third stage, D3 is the set initial duty cycle value in the third stage, t3 is the set third stage perforation time, F(t) is the output frequency value at a certain time in the third stage, F3' is the set terminal frequency value in the third stage, F3 is the set initial frequency value in the third stage, t3 is the set third stage perforation time, and t is the perforation time consumed from the beginning of the third stage to the current time.

[0138] Table 2 is the data of low duty cycle to ultra-low duty cycle with ultra-low frequency to low frequency and linear negative defocusing dynamic change. Table 2:

[0139]

[0140] Based on the above, in the third stage of the piercing process, in order to ensure that the slag is ejected from the hole during the piercing process and that the slag is solidified and the inner surface of the hole is as little as possible, by controlling the laser beam in the point frequency state, the metal inside the hole is still melted, and at the same time, with the increase of the piercing time, the light output duty cycle gradually decreases, which ensures that the piercing process in the third stage will not cause a burst hole due to the high real-time state energy, and at the same time, the focus gradually moves downward with the increase of the piercing time, which ensures that the super-thick plate material completes the penetration during the piercing process.

[0141] The above-mentioned laser piercing processing method of the super-thick plate can realize stable and non-burst hole of the super-thick plate, and is beneficial to the cutting of the thick plate. The traditional piercing method cannot complete the piercing of the super-thick plate, and the real-time energy is too high during the piercing process, which easily leads to the burning of the protective mirror and the accumulation of the piercing slag.

[0142] In summary, the laser piercing processing method provided by the embodiment has the following advantages: during the piercing process, the sine curve dynamic variable duty cycle, variable frequency and linear variable focus method are used, mainly referring to the low duty cycle to medium duty cycle in the second stage of piercing, medium frequency to low frequency, linear negative defocusing dynamic change and low duty cycle to ultra-low duty cycle in the third stage, ultra-low frequency to low frequency and linear negative defocusing dynamic change, which can realize the piercing of the super-thick plate, and ensure that the plate is penetrated without burst hole phenomenon.

[0143] Embodiment three

[0144] The embodiment also provides a numerical control system, which comprises a memory and a processor; the processor is used to execute the computer program stored in the memory to realize the steps of the laser piercing processing method in the numerical control system provided by any of the above-mentioned embodiments.

[0145] In the embodiment of the application, the processor calls the program or instruction stored in the memory, specifically, the program or instruction stored in the application program, and the processor is used to execute the method steps provided in the first aspect.

[0146] The method disclosed by the embodiments of the present application can be applied to a processor or implemented by a processor. The processor can be an integrated circuit chip having a processing capability of signals. In the implementation process, each step of the above method can be completed by integrated logic circuits or instructions in the form of software in the processor. The processor can be a general processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. Each method, step and logic block diagram disclosed in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor can be any conventional processor. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as a hardware code processor for execution, or a combination of hardware and software units in the code processor for execution. The software unit can be located in a random memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register or other mature storage medium in the art. The storage medium is located in the memory, and the processor reads the information in the memory and combines the hardware to complete the steps of the above method.

[0147] In another aspect, the embodiments of the present application also provide a computer readable storage medium for storing a computer program, wherein the computer program is executed by a processor to implement the steps of the laser perforation processing method of any of the above embodiments.

[0148] It should be noted that in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the claims, several apparatuses can be listed, which can be implemented by means of one and the same hardware. The use of the word "at least" followed by a list of one or more elements does not exclude additional elements. The use of the words "first", "second" and "third", etc. does not limit the number of these elements. These words are only used to distinguish between two or more elements or steps. The word "step" can not imply a logical or temporal precedence. The word "step" can be understood as a part of a process.

[0149] Moreover, it should be noted that in the description of the application, the terms "one embodiment", "some embodiments", "an embodiment", "an example", "a specific example" or "some examples" are intended to mean that a particular feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. The illustrative appearances of the above-described terms in various places in the specification are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics can be combined in any suitable manner in one or more embodiments or examples. Moreover, the terms "first", "second" and the like are used merely as labels, and are not intended to impose numerical requirements on their objects.

[0150] Although preferred embodiments of the application have been described herein, those skilled in the art will readily devise many other variations of these embodiments that will fall within the scope of the present application. Accordingly, the claims should be interpreted as including all embodiments falling within the scope of the application and all such modifications and alterations as would be apparent to those skilled in the art.

[0151] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A laser perforation machining method characterized by, The method is suitable for processing plate materials with a thickness of 60 mm or more, and the method comprises: S10, inputting basic parameters for laser perforation on an operation interface of a numerical control system; S20, after initialization of the numerical control system, controlling the cutting head to move to a reference position according to the basic parameters; the reference position is the initial value of the perforation height of the cutting head in the basic parameters; S30, sequentially performing perforation processing operations on the plate material to be processed according to the control parameters of the first stage, the second stage and the third stage, so that the plate material to be processed realizes stable perforation; when the plate material to be processed is penetrated, stopping the perforation according to the feedback information of the plate penetration feedback device; The basic parameters include: the perforation time period of the first stage, the second stage and the third stage; The control parameters of the cutting head in the first stage, the initial value and the dynamic change equation of the control parameters of the cutting head in the second stage and the third stage, the termination condition of the first stage, the termination condition of the second stage and the termination condition of the third stage; The first stage is a static piercing stage, and the second stage and the third stage are dynamic piercing stages; wherein the states of the duty cycle and the frequency are divided into three kinds, the first kind is a static state of high duty cycle, high frequency and positive focus, the second kind is a dynamic change of low duty cycle to high duty cycle, medium frequency to low frequency curve and linear negative defocusing, and the third kind is a dynamic change of low duty cycle to ultra-low duty cycle, super-low frequency to low frequency curve and linear negative defocusing; In the perforation process, in the second perforation stage and within time t2, the real-time duty cycle value d(t) is: ; D2’ a termination duty cycle value set for the second phase, D2 a start duty cycle value set for the second phase, t2 is a second phase punch time; real-time frequency value F(t) is: ; F2’ a termination frequency value set for the second phase, F2 a start frequency value set for the second phase, t is the time elapsed since the beginning of the second phase to the current time; The laser beam duty cycle value and the beam frequency at different times are in a complementary state.

2. The method of claim 1, wherein, In the S10, The perforation time period of the first stage is t1; The perforation time period of the second stage is t2; The perforation time period of the third stage is t3; The control parameters of the cutting head in the first stage include: perforation height, perforation frequency, perforation duty cycle, perforation power, perforation focus; The dynamic change equation of the perforation duty cycle, the perforation frequency and the perforation focus in the second stage, the initial value of the perforation duty cycle, the perforation frequency and the perforation focus; The dynamic change equation of the perforation duty cycle, the perforation frequency and the perforation focus in the third stage, the initial value of the perforation duty cycle, the perforation frequency and the perforation focus.

3. The method according to claim 2, wherein: The initial value of the perforation duty cycle in the second stage is lower than the value of the perforation duty cycle in the first stage, and the termination value of the perforation duty cycle is higher than the initial value of the perforation duty cycle in the second stage; The initial value and the termination value of the perforation frequency in the second stage are both lower than the value of the perforation frequency in the first stage; The initial value and the termination value of the perforation power in the second stage are both equal to the value of the perforation power in the first stage; The initial value of the perforation focus in the second stage is lower than the value of the perforation focus in the first stage, and the termination value of the perforation focus in the second stage is lower than the initial value of the perforation focus in the second stage; The initial value of the perforation duty cycle in the third stage is lower than the termination value of the perforation duty cycle in the second stage, and the termination value of the perforation duty cycle in the third stage is lower than the initial value of the perforation duty cycle in the third stage; The initial value of the third-stage piercing frequency is lower than the terminal value of the second-stage piercing frequency, and the terminal value of the third-stage piercing frequency is higher than the initial value of the third-stage piercing frequency. The initial value and the terminal value of the third-stage piercing power are both equal to the terminal value of the second-stage piercing power. The initial value of the third-stage piercing focus is higher than the terminal value of the second-stage piercing focus, and the terminal value of the third-stage piercing focus is lower than the initial value of the third-stage piercing focus.

4. The method of claim 2 or 3, wherein, the first-stage piercing frequency is greater than or equal to 1000 Hz, the first-stage piercing duty cycle is greater than or equal to 80%, and the first-stage focus is greater than or equal to 5 mm; the initial value of the first-stage piercing height is 1 / 3 to 1 / 2 of the thickness of the plate to be processed; after the first-stage piercing is completed, the depth of the pit formed in the plate to be processed is 1 / 4 to 1 / 3 of the thickness of the plate to be processed, and the width of the pit is 1 / 12 to 1 / 10 of the thickness of the plate to be processed.

5. The method of claim 2 or 3, wherein, the second-stage piercing duty cycle is between 40% and 60%, and the piercing focus is between -10 mm and -17 mm, the initial piercing focus of the second stage is higher than the terminal piercing focus of the second stage, and the dynamic change equation is y=kx; after the second-stage piercing is completed, the depth of the pit formed in the plate to be processed is 3 / 2 to 3 / 4 of the thickness of the plate to be processed, and the aperture is 1 / 15 to 1 / 13 of the thickness of the plate to be processed; and / or, the third-stage piercing frequency is between 20 Hz and 100 Hz, the piercing duty cycle is between 20% and 40%, and the piercing focus is between -30 mm and -15 mm; the initial value of the third-stage piercing height is 1 / 10 to 1 / 9 of the thickness of the plate to be processed.

6. The method according to claim 2 or 3, characterized in that, the termination condition of the first stage is that the piercing time of the first stage reaches a first set value; the termination condition of the second stage is that the piercing time of the second stage reaches a second set value; the termination condition of the third stage is that the piercing time of the third stage reaches a third set value.

7. The method of claim 2 or 3, wherein, The S30 comprises: the numerical control system performs piercing according to the control parameters of the first stage, and when the piercing reaches the termination condition of the first stage, the numerical control system controls the cutting head to stop piercing and adjusts the control parameters of the cutting head to the initial value of the control parameters of the second stage; the numerical control system performs piercing according to the control parameters of the second stage, and when the piercing reaches the termination condition of the second stage, the numerical control system controls the cutting head to stop piercing and adjusts the control parameters of the cutting head to the initial value of the control parameters of the third stage; the numerical control system performs piercing according to the control parameters of the third stage, and when the plate to be processed is penetrated, the piercing is stopped according to the feedback information of the plate penetration feedback device.

8. A numerical control system characterized by comprising: The device comprises a memory and a processor, the memory stores a computer program, and the processor executes the computer program to perform the method of any one of claims 1 to 7 to control the cutting head to stably pierce the plate to be processed.

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