Machining method of gantry machine tool beam guide rail

Abstract

The invention relates to the field of machining and manufacturing, aims to reduce the influence of deflection change of a cross beam and improve the precision of linear motion of a machine tool, and provides a machining method of a gantry machine tool cross beam guide rail. The gantry machine tool beam guide rail machining method comprises a to-be-machined beam, a machining machine tool and a collimator. Finite element analysis is conducted on the to-be-machined cross beam, and a reversible deformation curve S needed for machining the guide rail face of the to-be-machined cross beam is obtained. And the processing machine tool performs first-time processing on the guide rail surface of the to-be-processed cross beam according to the reversible deformation curve S. And the collimator detects the guide rail surface processed for the first time to obtain an error value of the processing machine tool. And the error value of the machining machine tool and the reversible deformation curve S are fitted to obtain a calibrated reversible deformation curve S1, the guide rail face is machined for the second time according to the calibrated reversible deformation curve S1, the guide rail face of the cross beam counteracts deflection changes after being assembled to the gantry machine tool, and the effects of reducing the deflection changes of the cross beam and improving the linear motion precision of the machine tool are achieved.

Description

Technical Field

[0001] The present application relates to the field of mechanical processing and manufacturing, and in particular, to a method for processing a crossbeam guide rail of a gantry machine tool. Background Art

[0002] The crossbeam is the main bearing part for the movement of the boring and milling parts of the gantry machine tool. Its main function is to serve as the main body of the Y-axis of the machine tool. The boring and milling head moves linearly along the crossbeam guide rail. The change in the accuracy of the crossbeam guide rail directly affects the straightness of the boring and milling head parts in the vertical and horizontal planes of the crossbeam movement. At present, the processing of the crossbeam guide rail mainly adopts the processing posture with the back of the crossbeam facing down and the guide rail facing up, and adopts two processing methods: gantry planer anti-deformation and CNC gantry milling anti-deformation: 1) The gantry planer anti-deformation processing method uses the high linear accuracy of the gantry planer to achieve the high straightness, flatness, parallelism and other precision requirements of the crossbeam guide rail. During processing, the crossbeam guide rail faces upward and is straightened according to the rough-machined guide rail side. The two ends of the crossbeam are pressed tightly, and the middle part uses a top pile to press the side of the crossbeam. According to empirical data, the middle part of the crossbeam guide rail is bent sideways. The difference between the middle and the two ends is checked by pulling the table to be within the pre-bending deformation value range of ±0.02. After tightening the workpiece, fine planing is performed. After the processing is completed, release the workpiece, the beam guide rail will rebound, and the required anti-deformation curve can be obtained. 2) The anti-deformation processing method of the CNC gantry milling machine is based on the anti-deformation processing of the gantry planer, using the same processing posture, using the programming compensation function of the CNC machine tool, and based on the experience summarized from long-term processing, the anti-deformation curve of the beam guide rail is processed by milling. When the guide rail faces upward, the required anti-deformation curve is programmed and processed, and the straightness of the guide rail is checked with a collimator. Then the beam is placed on its side to check the linear accuracy of the beam guide rail, and the difference in straightness between the two states is compared. The error is compensated by CNC interpolation to process the required anti-deformation curve.

[0003] In the prior art, the guide rail of the crossbeam is affected by the crossbeam's own weight, the boring and milling head components and other loads, causing the deflection to change, resulting in large precision errors in the vertical and horizontal planes of the machine tool. How to solve the above technical problems is what the technicians in this field need to consider. Summary of the invention

[0004] The present application provides a method for processing a beam guide rail of a gantry machine tool to solve the problem of how to reduce the influence of the deflection change of the beam and improve the accuracy of the linear motion of the machine tool.

[0005] An embodiment of the present application provides a method for processing a beam guide rail of a gantry machine tool, comprising a beam to be processed, a processing machine tool and a collimator. Finite element analysis is performed on the beam to be processed, and the working condition of the beam to be processed is simulated to calculate the deformation of the guide rail surface of the beam to be processed, and the inverse deformation curve S required for processing the guide rail surface of the beam to be processed is obtained based on the deformation. The beam to be processed is clamped, and the processing machine tool performs a first processing on the guide rail surface of the beam to be processed according to the inverse deformation curve S. In the clamped state of the beam to be processed, the collimator detects the guide rail surface after the first processing to obtain the linear accuracy of the guide rail surface, and the error value of the processing machine tool is obtained based on the linear accuracy and the inverse deformation curve S. The error value of the processing machine tool is fitted with the inverse deformation curve S to obtain a calibrated inverse deformation curve S1, and the guide rail surface is processed a second time according to the calibrated inverse deformation curve S1.

[0006] Compared with the prior art, the processing method of the gantry machine tool beam guide provided in this embodiment obtains the deformation of the guide surface of the beam to be processed through finite element analysis, thereby obtaining the inverse deformation curve S required for processing the guide surface; the guide surface is detected by a collimator for the first time, and the error value of the processing machine tool is obtained in combination with the inverse deformation curve S, and the error value of the processing machine tool is fitted with the inverse deformation curve S to eliminate the error of the processing machine tool itself. Therefore, the calibrated inverse deformation curve S1 has higher accuracy. The guide surface is processed for the second time according to the calibrated inverse deformation curve S1, so that the guide surface of the beam offsets the deflection change after being assembled to the gantry machine tool, so as to reduce the influence of the deflection change of the beam and improve the accuracy of the linear motion of the machine tool.

[0007] In a possible embodiment, the processing method of the gantry machine tool beam guide rail includes a pretreatment step: providing a blank, performing a first annealing treatment on the blank, then performing a rough milling process on the blank, performing a second annealing process on the processed blank, and then performing a semi-finishing milling process and a vibration aging process on the blank to form the beam to be processed.

[0008] In a possible implementation, simulating the working condition of the beam to be processed includes simulating the deformation of the load when the beam guide rail is working.

[0009] In a possible implementation, a fine milling cutter disc is provided, the fine milling cutter disc is mounted on the processing machine tool, and the cutter axis of the fine milling cutter disc is perpendicular to the guide rail surface.

[0010] In a possible implementation, during the first processing, the fine milling cutter disc leaves a margin on the guide rail surface, and the margin ranges from 0.48 mm to 0.52 mm.

[0011] In a possible implementation manner, the diameter of the fine milling cutter disc is 400 mm.

[0012] In a possible implementation, the machining machine includes a countersinking head, the cross-sectional profile of the countersinking head is L-shaped, and the finishing cutter disc is connected to the end of the countersinking head.

[0013] In a possible implementation, before clamping the beam to be processed, the beam to be processed is aligned, a pressure plate is used to clamp the beam to be processed to fix it, and the alignment data is rechecked. After confirming that the data has not changed, the beam to be processed is processed for the first time. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 A schematic diagram of a beam during processing according to an embodiment of the present application;

[0016] Figure 2 This is a schematic structural diagram of a crossbeam according to an embodiment of the present application;

[0017] Figure 3 It is a structural schematic diagram of a counter-counter milling head during processing of a beam according to an embodiment of the present application;

[0018] Figure 4 A schematic diagram of an inverse deformation curve of a guide rail surface of a beam according to an embodiment of the present application;

[0019] Figure 5 This is a schematic diagram of a method for machining a beam guide rail of a gantry machine tool according to an embodiment of the present application.

[0020] Description of main component symbols:

[0021] 1. Crossbeam; 11. Guide surface; 12. First reference surface; 13. Second reference surface; 2. Processing machine tool; 21. Finishing cutter head; 22. Countersinking head; 221. Connecting part; 222. Extending part; 223. Rotating shaft; F1. First load; F2. Second load; F3. Third load. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0023] Some embodiments of the present application are described in detail. In the absence of conflict, the following embodiments and features of the embodiments can be combined with each other.

[0024] Example

[0025] See also Figures 1 to 3 As shown, the present embodiment provides a method for processing a beam guide rail of a gantry machine tool, comprising a beam 1 to be processed, a processing machine tool 2 and a collimator. Finite element analysis is performed on the beam 1 to be processed, and the working condition of the beam 1 to be processed is simulated to calculate the deformation of the guide rail surface 11 of the beam 1 to be processed, and the inverse deformation curve S required for processing the guide rail surface 11 of the beam 1 to be processed is obtained according to the deformation. The beam 1 to be processed is clamped, and the processing machine tool 2 performs the first processing on the guide rail surface 11 of the beam 1 to be processed according to the inverse deformation curve S. In the clamped state of the beam 1 to be processed, the collimator detects the guide rail surface 11 after the first processing to obtain the linear accuracy of the guide rail surface 11, and the error value of the processing machine tool 2 is obtained according to the linear accuracy and the inverse deformation curve S. The error value of the processing machine tool 2 is fitted with the inverse deformation curve S to obtain a calibrated inverse deformation curve S1, and the guide rail surface 11 is processed for the second time according to the calibrated inverse deformation curve S1.

[0026] The processing method of the gantry machine tool crossbeam guide provided in the present embodiment obtains the deformation of the guide surface 11 of the crossbeam 1 to be processed by finite element analysis, thereby obtaining the inverse deformation curve S required for processing the guide surface 11; the guide surface 11 is detected by a collimator during the first processing, and the error value of the processing machine tool 2 is obtained in combination with the inverse deformation curve S, and the error value of the processing machine tool 2 is fitted with the inverse deformation curve S, thereby eliminating the error of the processing machine tool 2 itself. Therefore, the calibrated inverse deformation curve S1 has higher accuracy, and the guide surface 11 is processed for a second time according to the calibrated inverse deformation curve S1, so that the guide surface 11 of the crossbeam offsets the deflection change, so as to reduce the influence of the deflection change of the crossbeam and improve the accuracy of the linear motion of the machine tool.

[0027] In this embodiment, the beam 1 to be processed is clamped in a side-standing clamping manner, and a clamping support point is designed at the position of the assembly and installation fulcrum to restore the assembled state of the beam as much as possible.

[0028] Please combine Figure 2As shown, the beam is large in size and heavy in weight, and is subjected to bending deformation due to the boring and milling head and its own weight. The beam includes a first reference plane 12, a second reference plane 13 and a guide surface 11. The guide surface 11 is disposed between the first reference plane 12 and the second reference plane 13, and the guide surface 11 is perpendicular to the first reference plane 12 and the second reference plane 13, respectively. The guide surface 11 is subjected to a first load F1, the second reference surface 13 is subjected to a second load F2, and the side opposite to the first reference surface 12 is subjected to a third load F3. Using UG three-dimensional simulation software, a finite element static analysis of the beam is performed. The deformation of the guide surface 11 of the beam is the largest after being subjected to the first load F1, the second load F2, and the third load F3. Please combine the following: Figure 4 As shown, the reverse deformation of the guide rail surface 11 is analyzed and calculated to obtain a reverse deformation curve. The coordinate values ​​of the reverse deformation curve are shown in the following table:

[0029]

[0030] In one embodiment, the processing method of the gantry machine tool beam guide rail includes a pretreatment step: providing a blank, performing a first annealing treatment on the blank, then performing a rough milling process on the blank, performing a second annealing process on the processed blank, and then performing a semi-finishing milling process and a vibration aging process on the blank to form a beam 1 to be processed.

[0031] In this embodiment, the first annealing treatment after the blank casting is used to eliminate the internal stress of the blank casting process, and the second annealing treatment after rough milling is used to eliminate the internal stress of rough processing. Before the first processing, the blank is subjected to vibration aging treatment to balance the internal structural stress of the beam and improve the accuracy and stability of the beam straight line.

[0032] In one embodiment, simulating the working condition of the beam 1 to be processed includes simulating the deformation of the load when the beam is working.

[0033] In this embodiment, UG finite element analysis is used to simulate the deformation of the maximum load when the beam is working, and the anti-deformation curve required for assembly is optimized and generated.

[0034] In one embodiment, a fine milling cutter disc 21 is provided. The fine milling cutter disc 21 is installed on the processing machine tool 2 , and the cutter axis of the fine milling cutter disc 21 is perpendicular to the guide rail surface 11 .

[0035] In one embodiment, the first processing and the second processing are both fine milling processing.

[0036] During the first processing, the fine milling cutter disc 21 leaves a margin on the guide surface 11, and the margin ranges from 0.48 mm to 0.52 mm.

[0037] In this embodiment, the machining program is designed based on the theoretical inverse deformation curve, a trial cut is made on the guide surface 11 of the beam, and a laser collimator is used to detect the actual linear accuracy of the beam. The detected value includes the linear accuracy error of the machine tool itself.

[0038] During the second processing, the error value of the processing machine tool 2 is re-fitted with the theoretical anti-deformation curve, that is, the machine tool error value is compensated, and a new anti-deformation curve S1 interpolation program is re-derived. The precision milling guide surface 11 can be processed to have an error within ±0.02 with the theoretical curve.

[0039] In one embodiment, the diameter of the fine milling cutter disc 21 is 400 mm.

[0040] In one embodiment, the machining machine 2 includes a countersinking head 22 , the cross-sectional profile of the countersinking head 22 is L-shaped, and the finishing cutter disc 21 is connected to the end of the countersinking head 22 .

[0041] Please combine Figure 3 As shown, the countersinking head 22 includes a connecting portion 221, an extension portion 222 and a rotating shaft 223. One end of the connecting portion 221 is fixedly connected to the processing machine 2, and the other end extends in the vertical direction. The end of the connecting portion 221 is connected to the extension portion 222 to form a profile with an L-shaped cross section. The extension portion 222 extends in the horizontal direction toward a position away from the connecting portion 221, and the rotating shaft 223 is arranged at the end of the extension portion 222 extending in the vertical direction. The rotating shaft 223 is connected to the fine milling cutter disc 21 to drive the fine milling cutter disc 21 to rotate.

[0042] In one embodiment, before clamping the beam 1 to be processed, the beam 1 to be processed is aligned, a pressing plate is used to clamp the beam 1 to be processed to fix it, and the alignment data is rechecked. After confirming that the data has not changed, the beam 1 to be processed is processed for the first time.

[0043] In summary, please combine Figure 5As shown, the processing method of the crossbeam guide rail of the gantry machine tool provided in this embodiment provides a blank, performs a first annealing treatment on the blank, then performs rough milling on the blank, performs a second annealing treatment on the processed blank, and then performs semi-finishing milling and vibration aging treatment on the blank to form a crossbeam 1 to be processed. Finite element analysis is performed on the crossbeam 1 to be processed to obtain the inverse deformation curve S required for processing the guide rail surface 11 of the crossbeam 1 to be processed. The crossbeam 1 to be processed is clamped, and the processing machine 2 performs the first fine milling on the guide rail surface 11 of the crossbeam 1 to be processed according to the inverse deformation curve S. When the crossbeam 1 to be processed is clamped, the collimator detects the guide rail surface 11 after the first processing to obtain the linear accuracy of the guide rail surface 11, and the error value of the processing machine 2 is obtained according to the linear accuracy and the inverse deformation curve S. The error value of the processing machine 2 is fitted with the inverse deformation curve S to obtain a calibrated inverse deformation curve S1, and the processing machine 2 is programmed to compensate according to the calibrated inverse deformation curve S1 and processes the guide rail surface 11 for the second time. Finally, the machining dimensions of the guide rail surface 11 are inspected, and after quality inspection, the crossbeam is assembled to the gantry machine tool, and then the assembled guide rail surface 11 is inspected.

[0044] The above implementation modes are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the above preferred implementation modes, a person skilled in the art should understand that the technical solutions of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for processing a gantry machine tool crossbeam guide rail, characterized in that: include: Providing a beam to be processed, performing finite element analysis on the beam to be processed, simulating the working condition of the beam to be processed, so as to calculate the deformation of the guide rail surface of the beam to be processed, and obtaining an inverse deformation curve S required for processing the guide rail surface of the beam to be processed according to the deformation; Providing a processing machine tool, clamping the beam to be processed, and performing a first processing on the guide rail surface of the beam to be processed according to the inverse deformation curve S; Providing a collimator, in the clamped state of the beam to be processed, detecting the guide rail surface after the first processing to obtain the linear accuracy of the guide rail surface, and obtaining the error value of the processing machine tool according to the linear accuracy and the inverse deformation curve S; The error value of the processing machine tool is fitted with the anti-deformation curve S to obtain a calibrated anti-deformation curve S1, and the guide surface is processed a second time according to the calibrated anti-deformation curve S1.

2. The method for processing a gantry machine tool crossbeam guide rail according to claim 1, characterized in that: The processing method of the gantry machine tool crossbeam guide rail includes a pretreatment step: providing a blank, performing a first annealing treatment on the blank, then performing a rough milling process on the blank, performing a second annealing process on the processed blank, and then performing a semi-finishing milling process and a vibration aging process on the blank to form the crossbeam to be processed.

3. The method for processing a gantry machine tool crossbeam guide rail according to claim 1, characterized in that: Simulating the working condition of the beam to be processed includes simulating the deformation of the load when the beam is working.

4. The method for processing a gantry machine tool crossbeam guide rail according to claim 1, characterized in that: A fine milling cutter disc is provided, wherein the fine milling cutter disc is installed on the processing machine tool, and the cutter axis of the fine milling cutter disc is perpendicular to the guide rail surface.

5. The method for processing a gantry machine tool crossbeam guide rail according to claim 4, characterized in that: During the first processing, the fine milling cutter disc leaves a margin on the guide rail surface, and the range of the margin is between 0.48 mm and 0.52 mm.

6. The method for processing a gantry machine tool crossbeam guide rail according to claim 4, characterized in that: The diameter of the fine milling cutter disc is 400 mm.

7. The method for processing a gantry machine tool crossbeam guide rail according to claim 4, characterized in that: The processing machine tool comprises a countersinking head, the cross-sectional profile of the countersinking head is L-shaped, and the finishing cutter disc is connected to the end of the countersinking head.

8. The method for processing a gantry machine tool crossbeam guide rail according to claim 1, characterized in that: Before clamping the beam to be processed, align the beam to be processed, use a pressure plate to clamp the beam to be processed to fix it, and recheck the alignment data. After confirming that the data has not changed, perform the first processing on the beam to be processed.

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