A counter-deformation processing method for a transverse beam offset guide rail of a numerical control gantry milling machine

Abstract

The application discloses a kind of reverse deformation processing methods of CNC gantry milling machine beam offset guide rail, comprising the following steps: step one, 3D modeling of CNC gantry milling machine: using 3D design software, the mechanical structure of CNC gantry milling machine is simulated modeling;Step two, finite element static stress analysis is carried out to the beam of CNC gantry milling machine;The application utilizes new technology of finite element simulation, simulates and predicts the deformation of CNC gantry milling machine beam after stress, decomposes space deformation into two planes of vertical and horizontal, then utilizes high-precision CNC gantry milling machine or high-precision CNC gantry grinding machine, and carries out reverse deformation processing to beam guide rail surface, finally obtains the high precision of CNC gantry milling machine;The application predicts beam deformation, and carries out targeted reverse deformation by processing, and finally greatly improves the assembly efficiency and precision of CNC gantry milling machine.

Description

Technical Field

[0001] This invention belongs to the field of CNC gantry milling machine technology, specifically a reverse deformation machining method for the offset guide rail of a CNC gantry milling machine beam. Background Technology

[0002] As the main support and guiding component of a CNC gantry milling machine, the crossbeam is one of the most important components affecting the overall accuracy of the machine tool. Due to the weight and off-center load torque caused by the left and right movement of the cross slide and the up and down movement of the ram, the crossbeam will undergo corresponding bending and torsional deformation. This deformation will affect the positional accuracy of the tool held on the spindle at the lower end of the ram, thus affecting the machining accuracy of the machine tool.

[0003] The deformation of the crossbeam caused by the movement of moving parts has little impact on ordinary gantry milling machines with low precision requirements. However, as the precision requirements of CNC gantry milling machines continue to increase, the analysis and prevention of micro-deformation of the crossbeam components are becoming increasingly important.

[0004] To address the deformation caused by the movement of moving parts on the crossbeam, the design rigidity of the crossbeam is typically increased. In the early stages, deformation data was obtained through empirical design and prototype testing. More recently, software simulation optimization has been used to obtain a high-rigidity design structure.

[0005] Increasing the rigidity of the crossbeam often results in an increase in its weight, which in turn increases manufacturing costs. In particular, the crossbeam guide rails of conventional CNC gantry milling machines are offset, and the deformation caused by the movement of moving parts to the crossbeam guide rails is inconsistent in magnitude and direction. This results in poor regularity of the positional accuracy of the tool clamped on the spindle at the lower end of the slide, and the whole machine cannot take corresponding compensatory measures, so the overall accuracy of the machine tool cannot be improved. Summary of the Invention

[0006] In view of the above situation and to overcome the defects of the prior art, the present invention provides a reverse deformation machining method for the offset guide rail of the crossbeam of a CNC gantry milling machine, which effectively solves the problems raised in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for reverse deformation machining of an offset guide rail on a CNC gantry milling machine beam, comprising the following steps:

[0008] Step 1: 3D modeling of the CNC gantry milling machine:

[0009] The mechanical structure of the CNC gantry milling machine was simulated and modeled using 3D design software.

[0010] Step 2: Perform finite element static stress analysis on the crossbeam of the CNC gantry milling machine:

[0011] S1. Obtain the weight and center of gravity of the two components of the CNC gantry milling machine that have forces applied to the crossbeam;

[0012] S101, the cross slide assembly moves left and right along the guide rail on the cross beam, and the weight of the cross slide assembly is applied to the cross beam guide rail through the slider;

[0013] S102. The ram component moves up and down along the vertical guide rail of the cross slide. The weight of the ram component acts on the cross slide and is then transmitted to the cross beam guide rail.

[0014] S103. The position of the cross slide on the crossbeam is movable, and the position of the center of gravity is variable. Different positions of the center of gravity have different effects on the bending and torsional deformation of the crossbeam, requiring static stress analysis at multiple positions.

[0015] S104. The ram component moves up and down on the cross slide. Although the position of the center of gravity changes, the bending and torsional deformations acting on the cross beam through the cross slide do not change much at different center of gravity positions. Therefore, static stress analysis only needs to be performed at one position.

[0016] S2. Taking the beam as the research object, establish a mechanical model of the beam;

[0017] S201. Convert the weight of the cross slide and ram components into an external load and apply it to the crossbeam model;

[0018] S202. Perform static stress analysis on the crossbeam stress model using finite element software to obtain deformation diagrams of the crossbeam under different states, obtain the deformation values ​​at the slider position, and draw the deformation curve of the crossbeam.

[0019] S3. Handling the deformation curve of the crossbeam under variable load conditions:

[0020] S301. Decompose the deformation data of the beam under variable load into two directions: horizontal and vertical.

[0021] S302. Obtain deformation data of the upper and lower guide rails of the cross beam at the contact position of the slider of the moving part in two directions, horizontal and vertical, when the cross slide and ram components move to different positions.

[0022] S303. Draw the deformation curves of the upper and lower guide rails along the horizontal and vertical directions respectively;

[0023] S304. When the beam structure is symmetrical, the deformation curve is a symmetrical curve along the central section.

[0024] S305. Under normal circumstances, the deformation curve of the upper guide rail is concave in the vertical plane and convex in the horizontal plane; the surface of the lower guide rail is concave in the vertical plane and concave in the horizontal plane.

[0025] S4. Draw the inverse deformation curve of the crossbeam guide surface:

[0026] S401. Draw the curve in the opposite direction based on the deformation curve of the crossbeam;

[0027] S402. Adjust the curve appropriately based on the machine tool's other precision requirements for the assembled machine.

[0028] S5. Reverse deformation machining of the crossbeam guide surface:

[0029] S501. Using a high-precision CNC gantry milling machine or a high-precision CNC gantry grinding machine, the mounting surfaces of the upper and lower guide rails of the crossbeam are machined according to the reverse deformation curve.

[0030] S502, the deformation curve of the bottom surface of the upper guide rail installation corresponds to the deformation curve in the vertical plane of the upper guide rail, the deformation curve of the vertical surface of the upper guide rail installation corresponds to the deformation curve in the horizontal plane of the upper guide rail, the deformation curve of the bottom surface of the lower guide rail installation corresponds to the deformation curve in the horizontal plane of the lower guide rail, and the deformation curve of the vertical surface of the lower guide rail installation corresponds to the deformation curve in the vertical plane of the lower guide rail.

[0031] S6. Installation of the crossbeam guide rail:

[0032] The crossbeam guide rails are installed according to the planned anti-deformation curve;

[0033] S7. Verification and Adjustment:

[0034] After the crossbeam guide surface and guide rail are processed and installed in the opposite direction of the predicted deformation, the cross slide and slide block components are assembled. The weight of the cross slide and slide block components causes the crossbeam to deform. The deformation value basically offsets the reverse deformation of the crossbeam guide rail, and finally obtains high precision straightness of the movement of the cross slide and slide block.

[0035] By measuring the straightness of the cross slide and ram movement, feedback was used to correct the anti-deformation machining amount of the crossbeam guide rail, further improving the assembly accuracy.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] 1. This invention utilizes the new finite element simulation technology to simulate and predict the deformation of the crossbeam of a CNC gantry milling machine after being subjected to force. The spatial deformation is decomposed into two planes, vertical and horizontal. Then, a high-precision CNC gantry milling machine or a high-precision CNC gantry grinding machine is used to perform reverse deformation processing on the crossbeam guide surface, ultimately obtaining the high precision of the CNC gantry milling machine.

[0038] 2. This invention predicts the deformation of the crossbeam and performs targeted reverse deformation through processing, ultimately greatly improving the assembly efficiency and accuracy of CNC gantry milling machines;

[0039] 3. This method improves the accuracy of CNC gantry milling machines;

[0040] 4. Since the guide rail surface is pre-machined according to the reverse deformation curve, it avoids the need for manual grinding of the guide rail surface during subsequent assembly to adjust the accuracy, which would otherwise result in poor contact between the guide rail and the guide rail surface, thus improving the stability of the machine tool's accuracy. Attached Figure Description

[0041] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0042] In the attached diagram:

[0043] Figure 1 This is a schematic diagram of the force analysis of the cross slide and ram on the left side of the crossbeam of the present invention;

[0044] Figure 2 This is a schematic diagram showing the force analysis of the cross slide and ram at the center of the crossbeam in this invention;

[0045] Figure 3 This is a schematic diagram of the force analysis of the cross slide and ram on the right side of the crossbeam of the present invention;

[0046] Figure 4 This is a side view of the beam under stress analysis according to the present invention;

[0047] Figure 5 This is a schematic diagram of the finite element meshing of the model of the cross slide and ram components of the present invention when they are on the left side;

[0048] Figure 6 This is a schematic diagram of the finite element meshing of the model of the cross slide and ram component of the present invention when they are on the right side;

[0049] Figure 7 This is a schematic diagram of the finite element static stress analysis of the crossbeam when the cross slide and ram components of the present invention are on the left side;

[0050] Figure 8 This is a schematic diagram of the finite element static stress analysis of the crossbeam when the cross slide and ram components of the present invention are in the center;

[0051] Figure 9 This is a schematic diagram of the finite element static stress analysis of the crossbeam when the cross slide and ram components of the present invention are on the right side;

[0052] Figure 10 This is a schematic diagram illustrating an example of the deformation curves of the upper and lower guide rail surfaces of the crossbeam in the vertical plane according to the present invention.

[0053] Figure 11 This is a schematic diagram illustrating an example of the deformation curves of the upper and lower guide rail surfaces of the crossbeam in the horizontal plane according to the present invention.

[0054] Figure 12This is a schematic diagram illustrating an example of the upper and lower guide rails of the crossbeam of the present invention being installed in a reverse deformation configuration in the vertical plane.

[0055] Figure 13 This is a schematic diagram illustrating an example of the upper and lower guide rails of the crossbeam of the present invention being installed in a reverse deformation manner in the horizontal plane;

[0056] In the diagram: 1. Crossbeam; 2. External load of the cross slide assembly on the crossbeam; 3. External load of the ram assembly on the crossbeam; 4. Fixed constraint at the bottom left side of the crossbeam; 5. Fixed constraint at the bottom right side of the crossbeam. Detailed Implementation

[0057] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0058] Example 1, by Figure 1-13 This invention relates to a method for reverse deformation machining of an offset guide rail on a CNC gantry milling machine beam, comprising the following steps:

[0059] Step 1: 3D modeling of the CNC gantry milling machine:

[0060] The mechanical structure of the CNC gantry milling machine was simulated and modeled using 3D design software.

[0061] Step 2: Perform finite element static stress analysis on the crossbeam of the CNC gantry milling machine:

[0062] S1. Obtain the weight and center of gravity of the two components of the CNC gantry milling machine that have forces applied to the crossbeam;

[0063] S101, the cross slide assembly moves left and right along the guide rail on the cross beam, and the weight of the cross slide assembly is applied to the cross beam guide rail through the slider;

[0064] S102. The ram component moves up and down along the vertical guide rail of the cross slide. The weight of the ram component acts on the cross slide and is then transmitted to the cross beam guide rail.

[0065] S103. The position of the cross slide on the crossbeam is movable, and the position of the center of gravity is variable. Different positions of the center of gravity have different effects on the bending and torsional deformation of the crossbeam, requiring static stress analysis at multiple positions.

[0066] S104. The ram component moves up and down on the cross slide. Although the position of the center of gravity changes, the bending and torsional deformations acting on the cross beam through the cross slide do not change much at different center of gravity positions. Therefore, static stress analysis only needs to be performed at one position.

[0067] S2. Taking the beam as the research object, establish a mechanical model of the beam;

[0068] S201. Convert the weight of the cross slide and ram components into an external load and apply it to the crossbeam model;

[0069] S202. Perform static stress analysis on the crossbeam stress model using finite element software to obtain deformation diagrams of the crossbeam under different states, obtain the deformation values ​​at the slider position, and draw the deformation curve of the crossbeam.

[0070] S3. Handling the deformation curve of the crossbeam under variable load conditions:

[0071] S301. Decompose the deformation data of the beam under variable load into two directions: horizontal and vertical.

[0072] S302. Obtain deformation data of the upper and lower guide rails of the cross beam at the contact position of the slider of the moving part in two directions, horizontal and vertical, when the cross slide and ram components move to different positions.

[0073] S303. Draw the deformation curves of the upper and lower guide rails along the horizontal and vertical directions respectively;

[0074] S304. When the beam structure is symmetrical, the deformation curve is a symmetrical curve along the central section.

[0075] S305. Under normal circumstances, the deformation curve of the upper guide rail is concave in the vertical plane and convex in the horizontal plane; the surface of the lower guide rail is concave in the vertical plane and concave in the horizontal plane.

[0076] S4. Draw the inverse deformation curve of the crossbeam guide surface:

[0077] S401. Draw the curve in the opposite direction based on the deformation curve of the crossbeam;

[0078] S402. Adjust the curve appropriately based on the machine tool's other precision requirements for the assembled machine.

[0079] S5. Reverse deformation machining of the crossbeam guide surface:

[0080] S501. Using a high-precision CNC gantry milling machine or a high-precision CNC gantry grinding machine, the mounting surfaces of the upper and lower guide rails of the crossbeam are machined according to the reverse deformation curve.

[0081] S502, the deformation curve of the bottom surface of the upper guide rail installation corresponds to the deformation curve in the vertical plane of the upper guide rail, the deformation curve of the vertical surface of the upper guide rail installation corresponds to the deformation curve in the horizontal plane of the upper guide rail, the deformation curve of the bottom surface of the lower guide rail installation corresponds to the deformation curve in the horizontal plane of the lower guide rail, and the deformation curve of the vertical surface of the lower guide rail installation corresponds to the deformation curve in the vertical plane of the lower guide rail.

[0082] S6. Installation of the crossbeam guide rail:

[0083] The crossbeam guide rails are installed according to the planned anti-deformation curve;

[0084] S7. Verification and Adjustment:

[0085] After the crossbeam guide surface and guide rail are processed and installed in the opposite direction of the predicted deformation, the cross slide and slide block components are assembled. The weight of the cross slide and slide block components causes the crossbeam to deform. The deformation value basically offsets the reverse deformation of the crossbeam guide rail, and finally obtains high precision straightness of the movement of the cross slide and slide block.

[0086] By measuring the straightness of the cross slide and ram movement, feedback was used to correct the anti-deformation machining amount of the crossbeam guide rail, further improving the assembly accuracy.

[0087] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0088] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for inverse deformation machining of a deflected rail of a CNC gantry milling machine beam, characterized in that, Comprise the following steps: Step one, 3D modeling of CNC gantry milling machine: Using 3D design software, the mechanical structure of CNC gantry milling machine is simulated modeling; Step two, finite element static stress analysis of the beam of CNC gantry milling machine: S1, get the weight and center of gravity of the two components of CNC gantry milling machine which have force exerted on the beam; S101, cross slide component moves left and right along the guide rail on the beam, the weight of cross slide component acts on the guide rail of the beam through the slider; S102, ram component moves up and down along the vertical guide rail of cross slide, the weight of ram component acts on the cross slide, and then is transmitted to the guide rail of the beam; S103, the position of cross slide on the beam is movable, and the position of the center of gravity is variable. Different positions of the center of gravity have different effects on the bending and torsional deformation of the beam, so multi-position static stress analysis is needed; S104, the ram component moves up and down on the cross slide. Although the position of the center of gravity is variable, the bending and torsional deformation of the beam through the cross slide is not much different at different positions of the center of gravity, so static stress analysis is only needed at one position; S2, taking the beam as the research object, a mechanical model of the beam is established; S201, the weight of cross slide and ram component is converted into external load and applied to the beam model; S202, finite element software static stress analysis is carried out on the beam stress model, the deformation diagram of the beam under different conditions is obtained, the deformation value at the slider position is obtained, and the deformation curve diagram of the beam is drawn; S3, processing the deformation curve of the beam under variable load: S301, decompose the deformation data of the beam under variable load into two directions of horizontal and vertical plane; S302, obtain the decomposition of the deformation data of the beam under variable load into two directions of horizontal and vertical plane at the contact position of the slider of the moving component when the cross slide and ram component move to different positions; S303, draw the deformation curve of the upper and lower guide rails along the horizontal and vertical plane respectively; S304, in the case of symmetry of the beam structure, the deformation curve is a symmetric curve along the central section; S305, under normal circumstances, the deformation curve of the upper guide rail is concave in the vertical plane and convex in the horizontal plane; the deformation curve of the lower guide rail is concave in the vertical plane and concave in the horizontal plane; S4, draw the inverse deformation curve of the beam guide rail surface: S401, draw the inverse curve according to the deformation curve of the beam; S402, adjust the curve appropriately according to the other precision requirements of the machine tool after the whole machine is assembled; S5, inverse deformation processing of the beam guide rail surface: S501, use high-precision CNC gantry milling machine or high-precision CNC gantry grinding machine to process the mounting surface of the upper and lower guide rails of the beam according to the inverse deformation curve; S502, the upper guide rail mounting bottom surface of the beam corresponds to the deformation curve of the upper guide rail in the vertical plane, the upper guide rail mounting vertical surface corresponds to the deformation curve of the upper guide rail in the horizontal plane, the lower guide rail mounting bottom surface corresponds to the deformation curve of the lower guide rail in the horizontal plane, and the lower guide rail mounting vertical surface corresponds to the deformation curve of the lower guide rail in the vertical plane; S6, installation of the beam guide rail: The beam guide rail is installed according to the planned inverse deformation curve; S7, verification and adjustment: After the beam rail surface and the rail are processed and installed in the opposite direction of the predicted deformation, the cross slide and the ram components are assembled. The weight of the cross slide and the ram components causes the beam to deform, and the deformation value substantially offsets the reverse deformation amount of the beam rail. Finally, the cross slide and the ram move with high-precision straightness. After the straightness of the cross slide and the ram is measured, the reverse deformation processing amount of the beam rail is corrected based on feedback, and the assembly precision is further improved.

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