Pipe center calibration method and laser processing machine

Abstract

The present invention relates to a method for calibrating the center of a pipe and a laser processing machine. The calibration method includes: rotating the pipe in a first direction by a first angle, and a height sensor subsequently measuring a first vertical coordinate; rotating the pipe in a second direction by a first angle, and subsequently measuring a second vertical coordinate; determining the upper horizontal coordinate of the rotation center based on the horizontal position of the sensor when the first vertical coordinate equals the second vertical coordinate, and subsequently measuring the upper vertical coordinate; with the sensor positioned above the lower surface of the pipe, rotating the pipe in the first direction by a second angle, and subsequently measuring a third vertical coordinate; rotating the pipe in a second direction by a second angle, and subsequently measuring a fourth vertical coordinate; determining the lower horizontal coordinate of the rotation center based on the horizontal position of the sensor when the third vertical coordinate equals the fourth vertical coordinate, and subsequently measuring the lower vertical coordinate; determining the horizontal coordinate of the rotation center based on the upper and lower horizontal coordinates, and determining the vertical coordinate based on the upper and lower vertical coordinates. The calibration method of the present invention is applicable to pipes of various shapes.

Description

Technical Field

[0001] The present application generally relates to the field of electronic control, and more specifically, to a method for calibrating the center of a pipe and a laser processing machine. Background Art

[0002] The coordinates of the rotation center of the pipe are parameters that cannot be obtained in three-dimensional pipe processing, and they directly determine the processing accuracy of three-dimensional pipes. There are many ways to confirm the rotation center of the pipe. One is to use manual measurement input and repeatedly test and adjust the processing. This method is inaccurate, and frequent trial processing and adjustment are time-consuming and labor-intensive. Another method is to use a tool setter for calibration. This method requires the use of an expensive tool setter, which is costly and complex to operate, and has certain requirements for the user. In recent years, the use of non-chamfered square tubes for rotation center calibration has also been developed, but the demand for precision pipe cutting and special-shaped small tube cutting has increased rapidly. In order to improve the clamping accuracy, customized clamps are generally used, which makes it impossible to clamp the square tube for calibration. The above methods are relatively complicated, and there are deviations in the processing accuracy. Summary of the Invention

[0003] The present application provides a pipe center calibration method and a laser processing machine to solve the problem of complex calibration of the existing pipe rotation center.

[0004] In order to solve the above technical problems, the present invention provides a method for calibrating the center of a pipe, comprising: placing a height sensing element above the upper surface of the pipe, and after the pipe is rotated in a first direction by ∆θ degrees, following measurement to obtain a vertical coordinate z1; after the pipe is rotated in a second direction by the ∆θ degrees, following measurement to obtain a vertical coordinate z2; determining the upper horizontal coordinate Rx1 of the pipe rotation center according to the horizontal position of the height sensing element when the vertical coordinate z1 is equal to the vertical coordinate z2, and following measurement of the upper vertical coordinate Rz1; rotating the pipe 180 degrees, with the height sensing element located above the lower surface of the pipe, After the pipe rotates ∆θ degrees in the first direction, the vertical coordinate z3 is obtained by follow-up measurement; after the pipe rotates ∆θ degrees in the second direction, the vertical coordinate z4 is obtained by follow-up measurement; according to the horizontal position of the height sensing component when the vertical coordinate z3 is equal to the vertical coordinate z4, the lower horizontal coordinate Rx2 of the pipe rotation center is determined, and the lower vertical coordinate Rz2 is measured; the horizontal coordinate Rx of the rotation center is determined according to the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2, and the vertical coordinate Rz of the rotation center is determined according to the upper vertical coordinate Rz2 and the lower vertical coordinate Rz2.

[0005] In one embodiment, the method of determining the upper horizontal coordinate Rx1 of the center of rotation of the pipe according to the horizontal position of the height sensor when the vertical coordinate z1 is equal to the vertical coordinate z2 includes: if the coordinates z1 and z2 are not equal, then moving the height sensor horizontally and then rotating the pipe in the first direction again. degrees, and obtain the vertical coordinate z1 by following the measurement; rotate the pipe in the second direction degrees, and obtain the vertical coordinate z2 by following the measurement; compare z1 and z2, and iterate in this way until z1 is equal to z2; the horizontal position of the height sensor when the vertical coordinate z3 is equal to the vertical coordinate z4 determines the lower horizontal coordinate Rx2 of the center of rotation of the pipe, including: if the coordinates z3 and z4 are not equal, then move the height sensor horizontally, and then rotate the pipe in the first direction again degrees, and then obtain the vertical coordinate z3 by following the measurement; rotate the pipe in the second direction Degrees, follow the measurement to obtain the vertical coordinate z4; compare z3 and z4, and iterate in this way until z3 is equal to z4.

[0006] In one embodiment, the calibration method further includes: after the height sensing component is moved to the left by a distance △x from the upper horizontal coordinate, following measurement to obtain the vertical coordinate zp1; after the height sensing component is moved to the right by the distance △x from the upper horizontal coordinate, following measurement to obtain the vertical coordinate zp2; determining the horizontal inclination angle of the pipe according to the vertical coordinates zp1 and zp2; and performing horizontal correction on the pipe according to the horizontal inclination angle.

[0007] In one embodiment, the calibration method further includes: performing a first horizontal correction after determining the upper horizontal coordinate for the first time; determining the upper horizontal coordinate for the second time after performing the horizontal correction for the first time, and using the upper horizontal coordinate determined for the second time as the final upper horizontal coordinate; and performing a second horizontal correction after determining the upper horizontal coordinate for the second time.

[0008] In one embodiment, determining the horizontal tilt angle of the pipe according to the vertical coordinate zp1 and the vertical coordinate zp2 includes: the horizontal tilt angle is arctan[(zp1-zp2) / (2×△x)].

[0009] In one embodiment, determining the horizontal coordinate Rx of the rotation center according to the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2 includes: the horizontal coordinate Rx of the rotation center is (Rx1+ Rx2) / 2.

[0010] In one embodiment, the vertical coordinate Rz of the rotation center is determined based on the upper vertical coordinate Rz1 and the lower vertical coordinate Rz2, including: the vertical coordinate Rz of the rotation center is (Rz1+Rz2) / 2-H / 2-FollowDis, H is the vertical height of the pipe, and FollowDis is the follow height of the height sensor.

[0011] In one embodiment, the calibration method further includes: determining the horizontal deviation of the center of the pipe based on the upper horizontal coordinate Rx1, the lower horizontal coordinate Rx2 and the horizontal coordinate Rx of the rotation center; determining the vertical deviation of the center of the pipe based on the upper vertical coordinate Rz1, the lower vertical coordinate Rz1, the vertical height H of the pipe and the vertical coordinate Rz of the rotation center.

[0012] In one embodiment, the horizontal deviation of the pipe center is determined based on the upper horizontal coordinate Rx1, the lower horizontal coordinate Rx2 and the horizontal coordinate Rx of the rotation center, including: the horizontal deviation is ((Rx1×0.5-Rx)-(Rx2×0.5-Rx)) / 2.

[0013] In one embodiment, the vertical deviation of the center of the pipe is determined based on the upper vertical coordinate Rz1, the lower vertical coordinate Rz2 and the vertical height H of the pipe, including: the vertical deviation is ((Rz1-H×0.5)-(Rz2-H×0.5)) / 2.

[0014] In order to solve the above technical problems, the present invention provides a laser processing machine, including a laser head and a height sensing component, and the height sensing component is used to implement the above calibration method.

[0015] Different from the prior art, the calibration method of the pipe center of the present application uses a height sensor for measurement. Specifically, the height sensor is placed above the upper surface of the pipe. After the pipe is rotated in the first direction by ∆θ degrees, the vertical coordinate z1 is obtained by following the measurement; after the pipe is rotated in the second direction by the said ∆θ degrees, the vertical coordinate z2 is obtained by following the measurement; the upper horizontal coordinate Rx1 of the pipe rotation center is determined according to the horizontal position of the height sensor when the vertical coordinate z1 is equal to the vertical coordinate z2, and the upper vertical coordinate Rz1 is measured accordingly; the pipe is rotated 180 degrees, and the height sensor is located above the lower surface of the pipe. After the pipe is rotated in a first direction by ∆θ degrees, the vertical coordinate z3 is obtained by follow-up measurement; after the pipe is rotated in a second direction by ∆θ degrees, the vertical coordinate z4 is obtained by follow-up measurement; based on the horizontal position of the height sensor when the vertical coordinate z3 is equal to the vertical coordinate z4, the lower horizontal coordinate Rx2 of the pipe's rotation center is determined, and the lower vertical coordinate Rz2 is subsequently measured; the horizontal coordinate Rx of the rotation center is determined based on the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2, and the vertical coordinate Rz of the rotation center is determined based on the upper vertical coordinate Rz2 and the lower vertical coordinate Rz2. In this application, the rotation center is determined by utilizing the characteristic that the height of the rotation center remains unchanged when the pipe is rotated. This method is simple to operate and is applicable to pipes of various shapes, such as square and round. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an illustrative and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0017] Figure 1 1 is a flow chart of a method for calibrating the center of a pipe according to an embodiment of the present application;

[0018] Figure 2 This is a schematic diagram of measuring a height sensor when determining a horizontal coordinate in a method for calibrating a pipe center according to an embodiment of the present application;

[0019] Figure 3 is another flow chart of the method for calibrating the center of a pipe according to an embodiment of the present application;

[0020] Figure 4 This is a schematic diagram of measuring a height sensor during horizontal calibration in the method for calibrating the center of a pipe according to an embodiment of the present application;

[0021] Figure 5 Schematic diagram of the deviation between the rotation center and the pipe center in the pipe center calibration method according to an embodiment of the present application. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the embodiments described are part of the embodiments of the present disclosure, not all of them. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present disclosure.

[0023] The following describes in detail specific embodiments of the present disclosure, with reference to the accompanying drawings. This disclosure calibrates the rotation center of a pipe. Specifically, a height sensor is used as a sensor, leveraging the characteristics of the pipe during rotation to determine the rotation center. Furthermore, this disclosure can also determine the deviation between the rotation center and the pipe center, using this deviation to perform machining compensation and improve machining accuracy.

[0024] This application is used in the processing of pipes to calibrate the center of the pipe to facilitate position confirmation during pipe processing. Specifically, when processing pipes, the pipes are generally placed in a horizontal state, that is, the long axis of the pipe is in a horizontal state. If it is necessary to improve the processing accuracy of the pipe, the central axis of the pipe must be determined. This application is used to determine the central axis of the pipe. When the pipe is placed on the processing equipment, the processing equipment will rotate it. At this time, there will be a rotation center. This application can first measure the rotation center. If the processing equipment can clamp the pipe to ensure that the rotation center is consistent with the center of the pipe, such as using a pipe sleeve that fits the pipe to clamp, then the rotation center is the center of the pipe; if the processing equipment cannot clamp the pipe to ensure that the rotation center is consistent with the center of the pipe, the embodiment of this application can also calculate the deviation between the center of the pipe and the center of rotation.

[0025] Figure 1 This is a flow chart of a method for calibrating the center of a pipe according to an embodiment of the present application. In this method, since the pipe is placed horizontally, the horizontal plane where its central axis is located can be used as the dividing line to divide the pipe into upper and lower parts. The horizontal rotation center of the pipe, i.e., the horizontal coordinate of the rotation center, is then determined on the upper and lower surfaces of the pipe, respectively. The average of the horizontal rotation centers of the upper and lower surfaces is taken to determine the horizontal rotation center of the pipe. Vertical coordinate measurements are performed at the rotation centers of the upper and lower surfaces to determine the vertical rotation center, i.e., the vertical coordinate of the rotation center. The specific steps are as follows.

[0026] S11: The height sensor is placed above the upper surface of the pipe, and the pipe rotates in the first direction After the degree, the vertical coordinate z1 is obtained by following the measurement; the pipe rotates in the second direction After measuring the vertical coordinate z2, the vertical coordinate z2 is obtained.

[0027] To determine the horizontal rotation center of a pipe on its upper and lower surfaces, the pipe is rotated in a first and second direction, which can be clockwise or counterclockwise, and the position of the rotation center is determined by height measurement. At the location on the top surface corresponding to the rotation center, the pipe exhibits no height change during either clockwise or counterclockwise rotation, i.e., no change in the vertical direction perpendicular to the horizontal direction. However, at the location on the top surface corresponding to the non-rotation center, the pipe exhibits height change during both clockwise and counterclockwise rotation, thus enabling the determination of the rotation center through height measurement.

[0028] First, in this step, the height sensor is placed above the upper surface of the pipe, and the pipe rotates clockwise. After the degree, the vertical coordinate z1 is obtained by following the measurement; the pipe rotates counterclockwise After the degree is measured, the vertical coordinate z2 is obtained by follow-up measurement to determine whether the height sensing element is directly above the rotation center based on z1 and z2.

[0029] In this step, turn clockwise degrees and counterclockwise rotation The degrees are the same angles for left and right turns relative to the horizontal. If the height sensor is set at the center of rotation, the vertical coordinate measured will not change. If it is not at the center of rotation, it will change.

[0030] The specific measurement process of this step can be found in Figure 2 , Figure 2 The middle ellipse is the cross section of the pipe, and the element above the ellipse is the height sensor. During measurement, first move the height sensor to the approximate center position above the pipe, and then rotate the pipe to a roughly horizontal position. Control the pipe to rotate clockwise. degrees, for example 5°, then follow the measurement to obtain the vertical coordinate z1, such as Figure 2 (a) The so-called following measurement means that the height sensor follows the pipe below the sensor and measures the distance between the two.

[0031] The pipe rotates counterclockwise relative to the horizontal That is, on the basis of the pipe rotating 5° clockwise, the rotation axis is controlled to rotate 10° counterclockwise, and then the height sensor is used to follow again, and the Z-axis coordinate of the pipe at this position is measured to obtain the vertical coordinate z2, such as Figure 2 (b). In actual measurement, you can also rotate 5° counterclockwise and then 10° clockwise, which is a rotation of 5° compared to the horizontal.

[0032] S12: Determine the upper horizontal coordinate Rx1 of the pipe rotation center according to the horizontal position of the height sensor when the vertical coordinate z1 is equal to the vertical coordinate z2, and subsequently measure the upper vertical coordinate Rz1.

[0033] Therefore, in step S12, the upper horizontal coordinate Rx1 of the pipe's rotation center is determined based on the horizontal position of the height sensor when the vertical coordinate z1 equals the vertical coordinate z2. The upper horizontal coordinate of the rotation center represents the upper horizontal coordinate obtained when measuring the rotation center on the upper surface, and does not represent the final horizontal coordinate of the rotation center. During the specific measurement process, if z1 equals z2, no adjustment is required. If they are not equal, horizontal adjustment is required, and steps S11 and S12 are repeated after adjustment.

[0034] In this step, compare z1 and z2. If the coordinates z1 and z2 are not equal, move the height sensor horizontally and then rotate the pipe clockwise again. degrees, follow the measurement to obtain the vertical coordinate z1; rotate the pipe counterclockwise Degree, obtain the vertical coordinate z2 by following the measurement; compare z1 and z2 again, and iterate this loop until z1 is equal to z2.

[0035] In this step, compare z1 and z2. If z1 < z2, there is a deviation between the height sensing element and the rotation center, and it is biased towards the negative x direction. In this embodiment, the coordinates as shown are established. Figure 2 As shown, being biased towards the negative x direction means being biased to the left of the center of the pipe. Record the difference △z between z1 and z2 this time; control the height sensing element to step △x in the positive x direction.

[0036] If z1 > z2, there is a deviation between the cutting head nozzle and the rotation center, and it is biased towards the positive x direction. Record the difference △z between z1 and z2 this time; control the height sensing element to step △x in the negative x direction.

[0037] Where: The step △x can be set to a relatively large value first, such as 1 mm. When △z changes from negative to positive, or from positive to negative, adjust the step △x to a smaller value, such as 0.01 mm.

[0038] S13: Rotate the pipe 180 degrees. The height sensing element is above the lower surface of the pipe. After the pipe rotates degrees in the first direction, obtain the vertical coordinate z3 by following the measurement; after the pipe rotates degrees in the second direction, obtain the vertical coordinate z4 by following the measurement.

[0039] S14: Determine the lower horizontal coordinate Rx2 of the rotation center of the pipe according to the horizontal position of the height sensing element when the vertical coordinate z3 is equal to the vertical coordinate z4, and follow the measurement of the lower vertical coordinate Rz2.

[0040] The processes of steps S13 and S14 are similar to those of steps S11 and S12, and the lower horizontal coordinate Rx2 and the lower vertical coordinate Rz2 are obtained by using the same method logic for measurement.

[0041] S15: Determine the horizontal coordinate Rx of the rotation center according to the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2, and determine the vertical coordinate Rz of the rotation center according to the upper vertical coordinate Rz1 and the lower vertical coordinate Rz2.

[0042] After completing the above measurements, the coordinates of the rotation center can be obtained. Specifically, take half of the sum of the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2 as the horizontal coordinate Rx of the rotation center, Rx = (Rx1 + Rx2) / 2.

[0043] The vertical coordinate Rz of the rotation center = (Rz1 + Rz2) / 2 - H / 2 - FollowDis, where H is the vertical height of the pipe and FollowDis is the following height of the height sensing element.

[0044] In this embodiment, the rotation center is determined by utilizing the characteristic that the height of the rotation center remains unchanged when the pipe rotates. This method is simple to operate and is applicable to pipes of various shapes, such as square and round.

[0045] During the measurement process, the pipe may not be in a horizontal state at the beginning. In this case, the coordinates of the rotation center measured are not accurate. Therefore, a horizontal correction step can be added during the measurement process. Figure 3 , Figure 3 This is another flow chart of the method for calibrating the center of a pipe according to an embodiment of the present application. The method for calibrating the center of a pipe in this embodiment includes the following steps.

[0046] S21: The height sensor is placed above the upper surface of the pipe, and the pipe rotates in the first direction After the degree, the vertical coordinate z1 is obtained by following the measurement; the pipe rotates in the second direction After measuring the vertical coordinate z2, the vertical coordinate z2 is obtained.

[0047] S22: Determine the upper horizontal coordinate Rx1 of the pipe rotation center according to the horizontal position of the height sensing component when the vertical coordinate z1 is equal to the vertical coordinate z2, and subsequently measure the upper vertical coordinate Rz1.

[0048] Steps S21 and S22 are similar to steps S11 and S12 in the above embodiment and will not be further described. After determining the upper horizontal coordinate of the rotation center, the pipe is horizontally corrected. The principle of horizontal correction is that if the pipe is horizontal, the height of the pipe to the left and right of the rotation center is the same. Therefore, the height of the pipe to the left and right of the rotation center can be measured to determine whether the pipe is horizontal.

[0049] S23: When the height sensing element moves to the left by a first distance from the upper horizontal coordinate, the vertical coordinate zp1 is obtained by following the measurement; when the height sensing element moves to the right by a first distance from the upper horizontal coordinate, the vertical coordinate zp2 is obtained by following the measurement.

[0050] This step is to measure the height of the pipe on the left and right sides of the rotation center. Figure 4 understand. Figure 4 This is a measurement diagram of a height sensing component during horizontal correction in the pipe center calibration method according to an embodiment of the present application.

[0051] During this measurement step, the height sensor is controlled to move to Rx1, the upper horizontal coordinate of the pipe's rotation center. From there, it moves a distance △x in the positive x-axis direction. The capacitive height sensor is controlled to follow, and the z-axis coordinate of the pipe at this position, zp1, is measured. The cutting head nozzle is then controlled to translate in the negative direction 2*△x, that is, a distance △x to the right from the upper horizontal coordinate. The height sensor is then controlled to follow, and the z-axis coordinate of the pipe at this position, zp2, is measured.

[0052] S24: Determine the horizontal tilt angle of the pipe according to the vertical coordinate zp1 and the vertical coordinate zp2; and perform horizontal correction on the pipe according to the horizontal tilt angle.

[0053] The horizontal tilt angle of the upper surface of the pipe is determined to be arctan[(zp1-zp2) / (2×△x)]. The pipe can be horizontally corrected by controlling the pipe to rotate in the opposite direction according to the horizontal tilt angle.

[0054] In this embodiment, steps S21-S24 may be iteratively performed. For example, after the upper horizontal coordinate is first determined, a first horizontal correction is performed. After the first horizontal correction, the upper horizontal coordinate is second determined. After the second determination, a second horizontal correction is performed. The first determination is for a rough determination of the upper horizontal coordinate and a rough horizontal correction. The second determination is for a precise determination of the upper horizontal coordinate and a precise horizontal correction. The second determination of the upper horizontal coordinate is used as the final horizontal coordinate. Obviously, more iterations may be used to improve accuracy.

[0055] During the second determination of the upper horizontal coordinate, since a rough adjustment has already been made the first time, the height sensor's step △x can be adjusted directly to a larger value. The clockwise and counterclockwise rotation angles of the pipe can also be larger, such as 10°, to highlight the difference in the vertical coordinates and facilitate the adjustment of the horizontal coordinates.

[0056] S25: Follow the measurement of the upper vertical coordinate.

[0057] S26: Rotate the pipe 180 degrees, the height sensor is located above the lower surface of the pipe, and the pipe rotates in the first direction After the degree, the vertical coordinate z3 is obtained by following the measurement; the pipe rotates in the second direction After that, the vertical coordinate z4 is obtained by following the measurement.

[0058] S27: Determine the lower horizontal coordinate Rx2 of the pipe rotation center according to the horizontal position of the height sensor when the vertical coordinate z3 is equal to the vertical coordinate z4, and then measure the lower vertical coordinate Rz2.

[0059] S28: Determine the horizontal coordinate Rx of the rotation center according to the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2, and determine the vertical coordinate Rz of the rotation center according to the upper vertical coordinate Rz1 and the lower vertical coordinate Rz2.

[0060] After the pipe is horizontally calibrated, the upper vertical coordinate is measured, and the lower horizontal coordinate and the lower vertical coordinate are measured. Steps S25-S28 in this embodiment are similar to steps S12-S15 in the above embodiment, and will not be described in detail.

[0061] S29: Determine the horizontal deviation of the pipe center according to the upper horizontal coordinate Rx1, the lower horizontal coordinate Rx2 and the horizontal coordinate Rx of the rotation center; determine the vertical deviation of the pipe center according to the upper vertical coordinate Rz1, the lower vertical coordinate Rz1 and the vertical height H of the pipe.

[0062] In this embodiment, in addition to determining the rotation center, the deviation between the rotation center and the center of the pipe can also be determined. Figure 5 understand, Figure 5 Schematic diagram of the deviation between the rotation center and the pipe center in the pipe center calibration method according to an embodiment of the present application.

[0063] The horizontal offset OffsetX is ((Rx1×0.5-Rx)-(Rx2×0.5-Rx)) / 2, where Rx1 is the upper horizontal coordinate, Rx2 is the lower horizontal coordinate, and Rx is the horizontal coordinate.

[0064] The vertical deviation OffsetZ is ((Rz1-H×0.5)-(Rz2-H×0.5)) / 2, where Rz1 is the upper vertical coordinate, Rz2 is the lower vertical coordinate, and H is the vertical height.

[0065] After the deviation is measured, it can be used to compensate the machining model and included in the model coordinate transformation to improve machining accuracy.

[0066] This embodiment can calibrate the machine center of any symmetrical pipe, regardless of curved or flat surfaces or symmetrical structures, as long as bilateral symmetry is sufficient. This greatly expands its application range. It is particularly suitable for custom fixtures and those that require frequent fixture replacement. It can also measure the deviation between the pipe center and the machine's rotation center, and compensate for this deviation to further improve pipe cutting accuracy.

[0067] This application also proposes a laser processing machine comprising a laser head and a height sensor, which is used to implement the aforementioned pipe center calibration method. For example, in a laser cutting machine, a height sensor is typically provided in conjunction with the laser head, serving as the machine's height sensor. Therefore, the height sensor in the laser processing machine can be used to automatically perform calibration, eliminating the need for additional calibration components, reducing costs, and simplifying the calibration process for ease of use.

[0068] In the foregoing description of this specification, unless otherwise expressly specified or limited, terms such as "fixed," "mounted," "connected," or "connected" should be understood broadly. For example, the term "connected" can refer to a fixed connection, a removable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediary; or the internal connection between two components or the interaction between two components. Therefore, unless otherwise expressly defined in this specification, those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0069] According to the above description of this specification, those skilled in the art may also understand that the terms used below, such as "up", "down", "front", "back", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", "center", "longitudinal", "transverse", "clockwise" or "counterclockwise", etc., which indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the drawings of this specification, and are only for the purpose of facilitating the explanation of the scheme of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the device or element involved must have the specific orientation, be constructed and operate in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms cannot be understood or interpreted as limitations on the scheme of the present invention.

[0070] In addition, the terms "first" or "second" used in this specification to refer to numbers or ordinal numbers are used for descriptive purposes only and should not be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this specification, "plurality" means at least two, such as two, three or more, etc., unless otherwise clearly specified.

[0071] Although this specification has shown and described a number of embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will conceive of many modifications, variations, and alternatives without departing from the concept and spirit of the present invention. It should be understood that in practicing the present invention, various alternatives to the embodiments of the present invention described herein may be employed. The appended claims are intended to define the scope of protection of the present invention and therefore cover modular compositions, equivalents, or alternatives within the scope of these claims.

Claims

1. A method for calibrating the center of a pipe, characterized in that: The calibration method comprises: The height sensor is placed above the upper surface of the pipe, and the pipe rotates in the first direction After the degree, the vertical coordinate z1 is obtained by following the measurement; the pipe is rotated in the second direction After the degree, follow the measurement to obtain the vertical coordinate z2; Determine the upper horizontal coordinate Rx1 of the pipe rotation center according to the horizontal position of the height sensor when the vertical coordinate z1 is equal to the vertical coordinate z2, and subsequently measure the upper vertical coordinate Rz1; The pipe is rotated 180 degrees, and the height sensor is located above the lower surface of the pipe. The pipe rotates in the first direction. After the height sensor follows the measurement to obtain the vertical coordinate z3; the pipe rotates in the second direction After the degree, follow the measurement to obtain the vertical coordinate z4; Determine the lower horizontal coordinate Rx2 of the pipe rotation center according to the horizontal position of the height sensor when the vertical coordinate z3 is equal to the vertical coordinate z4, and subsequently measure the lower vertical coordinate Rz2; The horizontal coordinate Rx of the rotation center is determined according to the average value of the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2, and the vertical coordinate Rz of the rotation center is determined according to the upper vertical coordinate Rz2 and the lower vertical coordinate Rz2.

2. The calibration method according to claim 1, characterized in that: The method of determining the upper horizontal coordinate Rx1 of the pipe rotation center according to the horizontal position of the height sensing element when the vertical coordinate z1 is equal to the vertical coordinate z2 includes: If the z1 and z2 coordinates are not equal, the height sensor is moved horizontally and the pipe is rotated in the first direction again. degrees, and then obtain the vertical coordinate z1 by following the measurement; rotate the pipe in the second direction Degrees, follow the measurement to obtain the vertical coordinate z2; compare z1 and z2, and iterate in this way until z1 is equal to z2; The method of determining the lower horizontal coordinate Rx2 of the pipe rotation center according to the horizontal position of the height sensing element when the vertical coordinate z3 is equal to the vertical coordinate z4 includes: If the z3 and z4 coordinates are not equal, the height sensor is moved horizontally and then the pipe is rotated in the first direction again. degrees, and then obtain the vertical coordinate z3 by following the measurement; rotate the pipe in the second direction Degrees, follow the measurement to obtain the vertical coordinate z4; compare z3 and z4, and iterate in this way until z3 is equal to z4.

3. The calibration method according to claim 1, characterized in that: The calibration method further includes: After the height sensor moves to the left by a distance of △x from the upper horizontal coordinate, the vertical coordinate zp1 is obtained by following the measurement; after the height sensor moves to the right by the distance of △x from the upper horizontal coordinate, the vertical coordinate zp2 is obtained by following the measurement; Determine the horizontal inclination angle of the pipe according to the vertical coordinate zp1 and the vertical coordinate zp2; The pipe is horizontally corrected according to the horizontal inclination angle.

4. The calibration method according to claim 3, characterized in that: The calibration method further includes: Perform the first horizontal correction after the upper horizontal coordinate is determined for the first time; After the first horizontal correction, the upper horizontal coordinate is determined for the second time, and the upper horizontal coordinate determined for the second time is used as the final upper horizontal coordinate; After the upper horizontal coordinate is determined for the second time, the horizontal correction is performed for the second time.

5. The calibration method according to claim 3, characterized in that: Determining the horizontal inclination angle of the pipe according to the vertical coordinate zp1 and the vertical coordinate zp2 includes: The horizontal tilt angle is arctan[(zp1-zp2) / (2×△x)].

6. The calibration method according to claim 1, characterized in that: The determining the horizontal coordinate Rx of the rotation center according to the upper horizontal coordinate Rx1 and the lower horizontal coordinate Rx2 includes: The horizontal coordinate Rx of the rotation center is (Rx1+Rx2) / 2.

7. The calibration method according to claim 1, characterized in that: The determining the vertical coordinate Rz of the rotation center according to the upper vertical coordinate Rz1 and the lower vertical coordinate Rz2 includes: The vertical coordinate Rz of the rotation center is (Rz1+Rz2) / 2-H / 2-FollowDis, where H is the vertical height of the pipe, and FollowDis is the follow height of the height sensor.

8. The calibration method according to claim 1, characterized in that: The calibration method further includes: Determine the horizontal deviation of the center of the pipe according to the upper horizontal coordinate Rx1, the lower horizontal coordinate Rx2 and the horizontal coordinate Rx of the rotation center; The vertical deviation of the center of the pipe is determined according to the upper vertical coordinate Rz1, the lower vertical coordinate Rz2, the vertical height H of the pipe and the vertical coordinate Rz of the rotation center.

9. The calibration method according to claim 8, characterized in that: The determining of the horizontal deviation of the center of the pipe according to the upper horizontal coordinate Rx1, the lower horizontal coordinate Rx2 and the horizontal coordinate Rx of the rotation center includes: The horizontal deviation is ((Rx1×0.5-Rx)-(Rx2×0.5-Rx)) / 2.

10. The calibration method according to claim 8, characterized in that: The determining of the vertical deviation of the center of the pipe according to the upper vertical coordinate Rz1, the lower vertical coordinate Rz1 and the vertical height H of the pipe includes: The vertical deviation is ((Rz1-H×0.5)-(Rz2-H×0.5)) / 2.

11. A laser processing machine, characterized in that: The laser processing machine includes a laser head and a height sensing component, and the height sensing component is used to implement the calibration method according to any one of claims 1 to 10.

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