A thermal error compensation method and device for a laser numerical control system

Abstract

The present application relates to laser numerical control processing technical field, especially to a kind of thermal error compensation method and device of laser numerical control system, the method comprises: S1, the temperature value of the position where cutting head is located in laser numerical control system, the temperature value of specified position point on cutting head and the coordinate value of the position of each feed axis corresponding to the position where cutting head is located and the temperature value of corresponding screw rod of each feed axis corresponding to the position where cutting head is located are acquired in real time;S2, for the temperature value of specified position point on cutting head in laser numerical control system and the coordinate value of the position of each feed axis corresponding to the position where cutting head is located and the temperature value of corresponding screw rod of each feed axis corresponding to the position where cutting head is located, the temperature compensation coefficient corresponding to the temperature value of each screw rod respectively is determined in advance, the compensation amount corresponding to each feed axis is determined, and the operation of the feed axis is controlled by the compensation amount.

Description

A method and apparatus for thermal error compensation in a laser numerical control system Technical Field

[0001] This invention relates to the field of laser numerical control machining technology, and in particular to a method and apparatus for thermal error compensation in a laser numerical control system. Background Technology

[0002] Currently, when using laser CNC systems for machining, deformation of CNC machine tool components such as lead screws and cutting heads due to temperature changes can affect the machining accuracy of the CNC machine tool within the laser CNC system. Thermal deformation of the CNC machine tool not only affects the positioning accuracy of the tool feed but also introduces shape errors in the machined workpiece.

[0003] Therefore, reducing the adverse effects of thermal error deformation on the processing effect and improving processing quality and precision are urgent problems to be solved. Summary of the Invention

[0004] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a thermal error compensation method and device for a laser CNC system, which solves the technical problem that thermal error deformation of existing CNC machine tools not only affects the positioning accuracy of the tool feed, but also causes machining shape errors in the workpiece.

[0005] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0006] On the one hand, this embodiment provides a thermal error compensation method for a laser numerical control system, including:

[0007] S1. Real-time acquisition of the position of the cutting head in the laser CNC system, the temperature value of a specified position on the cutting head, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, and the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head;

[0008] S2. Based on the temperature value of a specified position on the cutting head in the laser CNC system, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head, and the pre-acquired temperature compensation coefficients corresponding to the temperature value of each lead screw, determine the compensation amount corresponding to each feed axis, and control the operation of the feed axis through the compensation amount.

[0009] Preferably, S2 specifically includes:

[0010] S21. For the temperature value at a specified position on the cutting head in the laser CNC system, obtain the corresponding thermal error compensation value of the cutting head;

[0011] S22. Based on the thermal error compensation value corresponding to the cutting head, the coordinate value of the position of any feed axis corresponding to the position of the cutting head, the temperature value T of the lead screw corresponding to the feed axis, and the temperature compensation coefficient corresponding to the temperature value T of the lead screw obtained in advance, the compensation amount corresponding to the feed axis is obtained by formula (1), and the operation of the feed axis is controlled by the compensation amount.

[0012] The formula (1) is:

[0013] ΔK x =K0+tanβ(T).(P x -P0);

[0014] ΔK x This is the compensation amount corresponding to the feed axis;

[0015] K0 is the thermal error compensation value corresponding to the cutting head;

[0016] tanβ(T) is the temperature compensation coefficient corresponding to the temperature value T of the lead screw, which is obtained in advance;

[0017] P0 is a pre-specified reference position point for this feed axis;

[0018] P x This refers to the coordinate value of the feed axis position corresponding to the location of the cutting head.

[0019] Preferably, S21 specifically includes:

[0020] For the temperature value at a specified position on the cutting head in the laser CNC system, a pre-acquired cutting head thermal error compensation model is used to obtain the corresponding thermal error compensation value of the cutting head.

[0021] The thermal error compensation model for the cutting head is as follows:

[0022] K0 = a1*t1 + ... + a i *t i +....+a n *t n ;

[0023] K0 is the thermal error compensation value corresponding to the cutting head;

[0024] t i The temperature value at the i-th specified location;

[0025] a i The coefficient for the temperature value at the i-th specified location point among the pre-acquired specified factors;

[0026] Where 2≤n≤10.

[0027] Preferably, the method further includes the following steps before S1:

[0028] Multiple temperature data sets of the cutting head are obtained, and the multiple temperature data sets are fitted to obtain the specific values ​​of the coefficients corresponding to the temperature values ​​at specified locations in the cutting head thermal error compensation model, so as to obtain the cutting head thermal error compensation model.

[0029] Each of the temperature data sets includes: the temperature values ​​at all specified locations on the cutting head and the thermal deformation offset of the cutting head corresponding to the temperature values ​​at all specified locations on the cutting head;

[0030] Among them, the thermal deformation offset of the cutting head corresponding to the temperature values ​​of all specified positions on the cutting head is the deformation of the cutting head relative to the cutting head in its non-working state, corresponding to the temperature values ​​of all specified positions on the cutting head.

[0031] Preferably, the thermal deformation offset of the cutting head is measured by a displacement sensor.

[0032] Preferably, the method further includes the following steps before S1:

[0033] Obtain multiple different information groups corresponding to each lead screw at temperature value T, and determine the temperature compensation coefficient corresponding to the lead screw at temperature value T based on the multiple different information groups corresponding to the lead screw at temperature value T.

[0034] Each information group includes: the position coordinate value and position error value of the feed axis corresponding to the lead screw;

[0035] The position error value was obtained by measuring with a laser interferometer;

[0036] The position error value is the deformation of the feed shaft corresponding to the lead screw in the first and second states;

[0037] The first state is the non-working state;

[0038] The second state is the state of the lead screw corresponding to the feed axis at a temperature value T.

[0039] Preferably, based on multiple different information groups corresponding to the lead screw at temperature T, a temperature compensation coefficient corresponding to the lead screw at temperature T is determined, specifically including:

[0040] Based on the multiple different information groups corresponding to the lead screw at temperature T, obtain the coordinate points that correspond one-to-one with each information group;

[0041] The x-axis value of each coordinate point is the position coordinate value of the feed axis corresponding to the lead screw in the information group corresponding to that coordinate point;

[0042] The y-axis value of each coordinate point is the position error value of the feed axis corresponding to the lead screw in the information group corresponding to that coordinate point;

[0043] By fitting multiple coordinate points, a fitted straight line corresponding to the temperature value T of the lead screw is obtained;

[0044] Based on the fitted straight line, determine the temperature compensation coefficient corresponding to the lead screw at temperature T;

[0045] Wherein, the temperature compensation coefficient corresponding to the lead screw at temperature T is the slope of the fitted straight line corresponding to the temperature value T.

[0046] Preferably, the method further includes the following steps before S1:

[0047] Based on the temperature value T of any feed axis screw corresponding to the current position of the cutting head, the temperature compensation coefficient corresponding to the screw at temperature value T is obtained by formula (2);

[0048] The formula (2) is:

[0049]

[0050] Where: T0 is the temperature of the lead screw when the position-related thermal error is 0, which is obtained in advance;

[0051] T max This refers to the maximum temperature value that the lead screw can reach after operation, which is obtained in advance.

[0052] Tk max For the pre-acquired temperature value T max The slope of the corresponding fitted line.

[0053] On the other hand, this embodiment also provides a thermal error compensation device for a laser numerical control system, including:

[0054] The monitoring module is used to acquire in real time the position of the cutting head in the laser CNC system, as well as the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head.

[0055] The first temperature sensor is used to collect the temperature value at a specified location on the cutting head;

[0056] The second temperature sensor is used to collect the temperature value of the lead screw corresponding to each feed axis at the position of the cutting head.

[0057] The processing device is used to determine the compensation amount corresponding to each feed axis based on the temperature value of a specified position point on the cutting head in the laser CNC system, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head, and the pre-acquired temperature compensation coefficients corresponding to the temperature value of each lead screw, and to control the operation of the feed axis through the compensation amount.

[0058] Preferably, the device further includes:

[0059] Displacement sensor and laser interferometer connected to the processing device;

[0060] Both the first temperature sensor and the second temperature sensor are connected to the processing device via a serial port;

[0061] The displacement sensor is connected to the processing device via an RJ45 connector.

[0062] The laser interferometer is connected to the processing device via a serial port and uses MScomm as the communication interface.

[0063] The beneficial effects of this invention are as follows: The thermal error compensation method for a laser CNC system of this invention obtains in real time the position of the cutting head in the laser CNC system, the temperature value of a designated point on the cutting head, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, and the temperature value of the corresponding lead screw of each feed axis. Then, based on the temperature value of the designated point on the cutting head in the laser CNC system, the thermal error compensation value corresponding to the cutting head can be obtained. Finally, based on the thermal error compensation value corresponding to the cutting head, the coordinate values ​​of the positions of any feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to the feed axis, and a pre-obtained temperature compensation coefficient corresponding to the temperature value of the lead screw, the compensation amount corresponding to the feed axis is obtained. The compensation amount obtained by the thermal error compensation method for a laser CNC system of this invention controls the operation of the feed axis, greatly reducing the adverse effects of thermal errors on the processing effect and improving processing quality and accuracy. Attached Figure Description

[0064] Figure 1 is a flowchart of a thermal error compensation method for a laser numerical control system according to the present invention;

[0065] Figure 2 is a schematic diagram of the measurement of the thermal deformation offset of the cutting head in an embodiment of the present invention;

[0066] Figure 3 is a schematic diagram of the measurement of the position coordinate value and position error value of the feed axis corresponding to the lead screw in an embodiment of the present invention;

[0067] Figure 4 is a schematic diagram of the thermal error compensation device of a laser numerical control system in an embodiment of the present invention.

[0068] Figure 5 is a schematic diagram of the thermal error compensation device of another laser numerical control system in an embodiment of the present invention.

[0069] Explanation of reference numerals in the attached figures

[0070] A: Cutting head;

[0071] B: Displacement sensor;

[0072] C: Pre-defined horizontal line;

[0073] 1: First location point;

[0074] 2: Second location point;

[0075] 3: Third position point;

[0076] 4: Fourth position point;

[0077] 5: Fifth position point. Detailed Implementation

[0078] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0079] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention can be understood more clearly and thoroughly, and that the scope of the present invention can be fully conveyed to those skilled in the art.

[0080] Referring to Figure 1, this embodiment provides a thermal error compensation method for a laser numerical control system, including:

[0081] S1. Real-time acquisition of the position of the cutting head in the laser CNC system, the temperature value of a specified point on the cutting head, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, and the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head.

[0082] S2. Based on the temperature value of a specified position on the cutting head in the laser CNC system, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head, and the pre-acquired temperature compensation coefficients corresponding to the temperature value of each lead screw, determine the compensation amount corresponding to each feed axis, and control the operation of the feed axis through the compensation amount.

[0083] Specifically, S2 includes:

[0084] S21. For the temperature value at a specified position on the cutting head in the laser CNC system, obtain the corresponding thermal error compensation value for the cutting head. In this embodiment, the thermal error compensation value corresponding to the cutting head is actually the thermal error compensation value corresponding to the elongation and sway of the cutting head.

[0085] In this embodiment, S21 specifically includes:

[0086] For the temperature value at a specified position on the cutting head in the laser CNC system, a pre-acquired cutting head thermal error compensation model is used to obtain the corresponding thermal error compensation value of the cutting head.

[0087] The thermal error compensation model for the cutting head is as follows:

[0088] K0 = a1*t1 + ... + a i *t i +....+a n *t n ;

[0089] K0 is the thermal error compensation value corresponding to the cutting head.

[0090] t i Let be the temperature value at the i-th specified location.

[0091] a i The coefficient for the temperature value at the i-th specified location point among the pre-acquired specified factors.

[0092] Where 2≤n≤10.

[0093] S22. Based on the thermal error compensation value corresponding to the cutting head, the coordinate value of the position of any feed axis corresponding to the position of the cutting head, the temperature value T of the lead screw corresponding to the feed axis, and the temperature compensation coefficient corresponding to the temperature value T of the lead screw obtained in advance, the compensation amount corresponding to the feed axis is obtained by formula (1), and the operation of the feed axis is controlled by the compensation amount.

[0094] The formula (1) is:

[0095] ΔK x =K0+tanβ(T).(P x -P0);

[0096] ΔK x This is the compensation amount corresponding to the feed axis.

[0097] K0 is the thermal error compensation value corresponding to the cutting head.

[0098] tanβ(T) is the temperature compensation coefficient corresponding to the temperature value T of the lead screw, which is obtained in advance.

[0099] P0 is a pre-specified reference position point for this feed axis.

[0100] P x This refers to the coordinate value of the feed axis position corresponding to the location of the cutting head.

[0101] In this embodiment, the comprehensive thermal error of each feed axis of the machine tool caused by each heat source of the machine tool is estimated according to formula (1), and the reverse compensation error value is generated and transmitted to the laser CNC system to pre-compensate the thermal error of different feed axes, thereby greatly reducing the adverse effect of thermal error on the processing effect and improving the processing quality and accuracy.

[0102] In practical applications, the thermal error compensation method for a laser numerical control system in this embodiment further includes the following steps before S1:

[0103] Multiple temperature data sets of the cutting head are obtained, and the multiple temperature data sets are fitted to obtain the specific values ​​of the coefficients corresponding to the temperature values ​​at specified locations in the cutting head thermal error compensation model, so as to obtain the cutting head thermal error compensation model.

[0104] Each set of temperature data includes: the temperature values ​​of all specified locations on the cutting head and the thermal deformation offset of the cutting head corresponding to the temperature values ​​of all specified locations on the cutting head.

[0105] Among them, the thermal deformation offset of the cutting head corresponding to the temperature values ​​of all specified positions on the cutting head is the deformation of the cutting head relative to the cutting head in its non-working state, corresponding to the temperature values ​​of all specified positions on the cutting head.

[0106] The thermal deformation offset of the cutting head is measured by a displacement sensor.

[0107] Referring to Figure 2, the method for measuring the thermal deformation offset of the cutting head in this embodiment is as follows: assuming that the designated position points on the cutting head A include: first position point 1, second position point 2, third position point 3, fourth position point 4, and fifth position point 5, a displacement sensor B is set on a pre-set horizontal line C, which is perpendicular to the cutting head A. The displacement sensor B is directly opposite the cutting head A. The displacement sensor B measures once when the cutting head A is not working (that is, when the temperature of the cutting head has not risen), respectively measuring the specific positions of the first position point 1, second position point 2, third position point 3, fourth position point 4, and fifth position point 5. Then, when the cutting head A is working, the specific positions of the designated position points are measured. At this time, the temperature values ​​at the designated position points on the cutting head A form a temperature data set. Finally, the specific positions of the first position point 1, the second position point 2, the third position point 3, the fourth position point 4, and the fifth position point 5 obtained from the two measurements are subtracted to obtain the position change of the first position point 1, the position change of the first position point 2, the position change of the first position point 3, the position change of the first position point 4, and the position change of the first position point 5. Then, the thermal deformation offset of the cutting head corresponding to this temperature data set is the total value of the position change of the first position point 1, the position change of the first position point 2, the position change of the first position point 3, the position change of the first position point 4, and the position change of the first position point 5.

[0108] In practical applications, the thermal error compensation method for a laser numerical control system in this embodiment further includes the following steps before S1:

[0109] Obtain multiple different information groups corresponding to each lead screw at temperature value T, and determine the temperature compensation coefficient corresponding to the lead screw at temperature value T based on the multiple different information groups corresponding to the lead screw at temperature value T.

[0110] Each information group includes: the position coordinates and position error values ​​of the feed axis corresponding to the lead screw.

[0111] The position error value was obtained by measuring with a laser interferometer.

[0112] The position error value is the deformation of the feed axis corresponding to the lead screw in the first state and the second state.

[0113] The first state is the non-working state.

[0114] The second state is the state of the lead screw corresponding to the feed axis at a temperature value T.

[0115] Referring to Figure 3, the position error value is measured in this embodiment as follows: assuming the current feed axis position coordinate is P5, the position error value is measured using a laser interferometer when the feed axis corresponding to the lead screw is not in operation. In this embodiment, the multiple different information groups corresponding to the lead screw at temperature T may include: the position coordinate of the feed axis corresponding to the lead screw at P4 and its corresponding position error value; the position coordinate of the feed axis corresponding to the lead screw at P6 and its corresponding position error value; the position coordinate of the feed axis corresponding to the lead screw at P3 and its corresponding position error value; the position coordinate of the feed axis corresponding to the lead screw at P2 and its corresponding position error value; the position coordinate of the feed axis corresponding to the lead screw at P1 and its corresponding position error value; and the position coordinate of the feed axis corresponding to the lead screw at P7 and its corresponding position error value.

[0116] In this embodiment, based on multiple different information groups corresponding to the lead screw at temperature T, a temperature compensation coefficient corresponding to the lead screw at temperature T is determined, specifically including:

[0117] Based on the multiple different information groups corresponding to the lead screw at temperature T, obtain the coordinate points that correspond one-to-one with each information group.

[0118] The x-axis value of each coordinate point is the position coordinate value of the feed axis corresponding to the lead screw in the information group corresponding to that coordinate point.

[0119] The y-axis value of each coordinate point is the position error value of the feed axis corresponding to the lead screw in the information group corresponding to that coordinate point.

[0120] By fitting multiple coordinate points, a fitted straight line corresponding to the temperature value T of the lead screw is obtained.

[0121] Based on the fitted straight line, the temperature compensation coefficient corresponding to the lead screw at temperature T is determined.

[0122] Wherein, the temperature compensation coefficient corresponding to the lead screw at temperature T is the slope of the fitted straight line corresponding to the temperature value T.

[0123] In another embodiment, the method further includes, before S1:

[0124] Based on the temperature value T of any feed axis lead screw corresponding to the current position of the cutting head, the temperature compensation coefficient corresponding to the lead screw at temperature value T is obtained by formula (2).

[0125] The formula (2) is:

[0126]

[0127] Where: T0 is the temperature of the lead screw when the position-related thermal error is 0, which is obtained in advance.

[0128] T max This refers to the maximum temperature value that the lead screw can reach after operation, which is obtained in advance.

[0129] Tk max For the pre-acquired temperature value T max The slope of the corresponding fitted line.

[0130] This embodiment of a thermal error compensation method for a laser CNC system involves real-time acquisition of the location of the cutting head in the laser CNC system, the temperature value of a designated point on the cutting head, the coordinates of the positions of each feed axis corresponding to the location of the cutting head, and the temperature value of the lead screw corresponding to each feed axis. Then, based on the temperature value of the designated point on the cutting head, a thermal error compensation value corresponding to the cutting head can be obtained. Finally, based on the thermal error compensation value, the coordinates of the position of any feed axis corresponding to the location of the cutting head, the temperature value of the lead screw corresponding to the feed axis, and a pre-acquired temperature compensation coefficient corresponding to the temperature value of the lead screw, the compensation amount corresponding to the feed axis is obtained. The compensation amount obtained by this thermal error compensation method for a laser CNC system controls the operation of the feed axis, greatly reducing the adverse effects of thermal errors on the processing effect and improving processing quality and accuracy.

[0131] On the other hand, referring to Figure 4, this embodiment also provides a thermal error compensation device for a laser numerical control system, including:

[0132] The monitoring module is used to acquire in real time the position of the cutting head in the laser CNC system, as well as the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head.

[0133] The first temperature sensor is used to collect the temperature value at a specified location on the cutting head.

[0134] The second temperature sensor is used to collect the temperature value of the lead screw corresponding to each feed axis at the position of the cutting head.

[0135] The processing device is used to determine the compensation amount corresponding to each feed axis based on the temperature value of a specified position point on the cutting head in the laser CNC system, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head, and the pre-acquired temperature compensation coefficients corresponding to the temperature value of each lead screw, and to control the operation of the feed axis through the compensation amount.

[0136] Referring to Figure 5, the device further includes:

[0137] The displacement sensor and laser interferometer are connected to the processing device.

[0138] Both the first temperature sensor and the second temperature sensor are connected to the processing device via a serial port. In this embodiment, the serial port can be RS-232.

[0139] The displacement sensor is connected to the processing device via an RJ45 connector.

[0140] The laser interferometer is connected to the processing device via a serial port and uses MScomm as the communication interface.

[0141] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0142] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0143] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," or "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," or "beneath" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0144] In the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0145] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for thermal error compensation in a laser numerical control system, characterized in that, include: S1. Real-time acquisition of the position of the cutting head in the laser CNC system, the temperature value of a specified position on the cutting head, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, and the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head; S2. Based on the temperature value of a specified position point on the cutting head in the laser CNC system, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head, and the pre-acquired temperature compensation coefficients corresponding to the temperature value of each lead screw, determine the compensation amount corresponding to each feed axis, and control the operation of the feed axis through the compensation amount; S2 specifically includes: S21. Based on the temperature value of the specified position point on the cutting head in the laser CNC system, obtain the thermal error compensation value corresponding to the cutting head; S22. Based on the thermal error compensation value corresponding to the cutting head, the coordinate value of the position of any feed axis corresponding to the position of the cutting head, the temperature value T of the lead screw corresponding to the feed axis, and the pre-obtained temperature compensation coefficient corresponding to the temperature value T of the lead screw, the compensation amount corresponding to the feed axis is obtained by formula (1), and the operation of the feed axis is controlled by the compensation amount; the formula (1) is: ； This is the compensation amount corresponding to the feed axis; This is the thermal error compensation value corresponding to the cutting head; This is the temperature compensation coefficient corresponding to the temperature value T of the lead screw, which is obtained in advance; The reference position point for this feed axis, as specified in advance; This refers to the coordinate value of the feed axis position corresponding to the location of the cutting head.

2. The thermal error compensation method for a laser numerical control system according to claim 1, characterized in that, S21 specifically includes: for the temperature value at a specified position on the cutting head in the laser CNC system, using a pre-acquired cutting head thermal error compensation model, obtaining the corresponding thermal error compensation value for the cutting head; the cutting head thermal error compensation model is: =a1*t1+...+a i *t i +....+a n *t n ; This is the thermal error compensation value corresponding to the cutting head; t i The temperature value at the i-th specified location; a i The coefficient for the temperature value at the i-th specified location point among the pre-acquired specified factors; where 2≤n≤10.

3. The thermal error compensation method for a laser numerical control system according to claim 2, characterized in that, The method further includes, before S1: acquiring multiple temperature data sets of the cutting head, and fitting the multiple temperature data sets to obtain specific values ​​of the coefficients corresponding to the temperature values ​​at specified locations in the cutting head thermal error compensation model, so as to obtain the cutting head thermal error compensation model; each temperature data set includes: the temperature values ​​at all specified locations on the cutting head and the thermal deformation offset of the cutting head corresponding to the temperature values ​​at all specified locations on the cutting head; wherein, the thermal deformation offset of the cutting head corresponding to the temperature values ​​at all specified locations on the cutting head is the deformation of the cutting head relative to the cutting head in its non-working state.

4. The thermal error compensation method for a laser numerical control system according to claim 3, characterized in that, The thermal deformation offset of the cutting head is measured by a displacement sensor.

5. The thermal error compensation method for a laser numerical control system according to claim 4, characterized in that, The method further includes, before S1: acquiring multiple different information groups corresponding to each lead screw at temperature T, and determining a temperature compensation coefficient corresponding to the lead screw at temperature T based on the multiple different information groups corresponding to the lead screw at temperature T; wherein, each information group includes: the position coordinate value and position error value of the feed axis corresponding to the lead screw; the position error value is obtained by measuring with a laser interferometer; the position error value is the deformation of the feed axis corresponding to the lead screw in a first state and a second state; the first state is a non-working state; the second state is the state of the lead screw corresponding to the feed axis at temperature T.

6. The thermal error compensation method for a laser numerical control system according to claim 5, characterized in that, Based on multiple different information groups corresponding to the lead screw at temperature T, a temperature compensation coefficient corresponding to the lead screw at temperature T is determined. Specifically, this includes: obtaining coordinate points corresponding to each of the multiple different information groups at temperature T; the x-axis value of each coordinate point is the position coordinate value of the feed axis corresponding to the lead screw in the information group corresponding to that coordinate point; the y-axis value of each coordinate point is the position error value of the feed axis corresponding to the lead screw in the information group corresponding to that coordinate point; fitting multiple coordinate points to obtain a fitted straight line corresponding to the lead screw at temperature T; and determining the temperature compensation coefficient corresponding to the lead screw at temperature T based on the fitted straight line; wherein, the temperature compensation coefficient corresponding to the lead screw at temperature T is the slope of the fitted straight line corresponding to that temperature T.

7. The thermal error compensation method for a laser numerical control system according to claim 4, characterized in that, The method further includes, before S1: obtaining the temperature compensation coefficient corresponding to the lead screw at temperature T based on the temperature value T of any feed axis lead screw corresponding to the current position of the cutting head using formula (2); the formula (2) is: Where: T0 is the pre-acquired temperature of the lead screw when the position-related thermal error is 0; T max Tk is the maximum temperature that the lead screw can reach after operation, obtained in advance; max For the pre-acquired temperature value T max The slope of the corresponding fitted line.

8. A thermal error compensation device for a laser numerical control system, characterized in that, include: The monitoring module is used to acquire in real time the position of the cutting head in the laser CNC system and the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head; the first temperature sensor is used to collect the temperature value at a specified position on the cutting head; The second temperature sensor is used to collect the temperature value of the lead screw corresponding to each feed axis at the position of the cutting head. The processing device is used to determine the compensation amount corresponding to each feed axis based on the temperature value of a specified position point on the cutting head in the laser CNC system, the coordinate values ​​of the positions of each feed axis corresponding to the position of the cutting head, the temperature value of the lead screw corresponding to each feed axis corresponding to the position of the cutting head, and the pre-acquired temperature compensation coefficients corresponding to the temperature value of each lead screw, and to control the operation of the feed axis through the compensation amount; specifically, it includes: obtaining the thermal error compensation value corresponding to the cutting head based on the temperature value of the specified position point on the cutting head in the laser CNC system; Based on the thermal error compensation value corresponding to the cutting head, the coordinate value of any feed axis corresponding to the position of the cutting head, the temperature value T of the lead screw corresponding to the feed axis, and the pre-obtained temperature compensation coefficient corresponding to the temperature value T of the lead screw, the compensation amount corresponding to the feed axis is obtained by formula (1), and the operation of the feed axis is controlled by the compensation amount; the formula (1) is: ； This is the compensation amount corresponding to the feed axis; This is the thermal error compensation value corresponding to the cutting head; This is the temperature compensation coefficient corresponding to the temperature value T of the lead screw, which is obtained in advance; The reference position point for this feed axis, as specified in advance; This refers to the coordinate value of the feed axis position corresponding to the location of the cutting head.

9. The thermal error compensation device for the laser numerical control system according to claim 8, characterized in that, The device further includes: a displacement sensor and a laser interferometer connected to the processing device; wherein the first temperature sensor and the second temperature sensor are both connected to the processing device via serial ports; the displacement sensor is connected to the processing device via an RJ45 connector; and the laser interferometer is connected to the processing device via a serial port and uses MScomm as the communication interface.

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