Three-point support structure, design method, medium and computing device of five-axis numerical control machine tool

Abstract

The present application relates to the field of mechanical processing equipment, discloses a kind of three-point support structure of five-axis numerical control machine tool, design method, medium and computing device, it includes: the position of the pad iron of machine tool bed is dynamically optimized, determines pad iron position parameter information;According to pad iron position parameter, with machine tool workspace as the basis, the three-point support position of machine tool is determined, while reducing the weight of dynamic beam, so that the projection of each component total centroid on the bed surface on bed is in the triangle area surrounded by three-point support;The movement direction of the determined three-point support is restricted in simulation, to simulate the real three-point support state;Workpiece weight on machine tool, tool cutting force are applied, statics analysis is carried out, and the stress distribution result of machine tool under three-point support state is obtained by solving, to adjust and optimize machine tool structure or support mode to obtain optimal scheme.The present application improves the stability and precision of machine tool, and is more flexible when adjusting quickly.

Description

Technical Field

[0001] This invention relates to the field of machining equipment technology, and in particular to a three-point support structure, design method, medium, and computing device for a five-axis CNC machine tool. Background Technology

[0002] A five-axis machining center is a machine tool capable of machining in five axes, typically including three linear axes and two rotary axes. Five-axis machine tools can perform multi-faceted machining of complex parts, improving machining efficiency and accuracy. They can complete various machining operations through cutting at different angles, reducing tool change frequency and saving machining time. They are suitable for machining parts with high requirements for curved surfaces and can complete machining tasks involving various complex shapes. However, compared to traditional three-axis machining centers, five-axis machine tools are generally more expensive, requiring a larger investment. Programming and operation are relatively complex, requiring specialized technicians for operation and maintenance.

[0003] The leveling of the machine tool bed has a significant impact on machining stability and accuracy. Improper bed leveling can lead to machine tool vibration, decreased machining quality, and shortened equipment lifespan. Traditional machine beds are often supported by several shims, resulting in numerous contact points, which is not conducive to bed leveling. Summary of the Invention

[0004] To address the aforementioned problems, the purpose of this invention is to provide a three-point support structure, design method, medium, and computing device for a five-axis CNC machine tool, which improves the stability and accuracy of the machine tool, makes it more flexible during rapid adjustments, and provides a more reliable guarantee for production.

[0005] To achieve the above objectives, in a first aspect, the technical solution adopted by the present invention is as follows: a three-point support structure design method for a five-axis CNC machine tool, comprising: dynamically optimizing the position of the shims on the machine tool bed, determining the shim position parameter information to improve the dynamic performance of the bed; determining the three-point support position of the machine tool based on the shim position parameters and the machine tool workspace, while reducing the weight of the moving beam so that the projection of the total center of mass of each component on the bottom surface of the machine tool bed is always within the triangular area enclosed by the three-point support; fixing and constraining the determined three-point support, i.e., the contact surface between the bottom surface of the shim and the ground, restricting all degrees of freedom in the simulation, simulating the real three-point support state to ensure the accuracy of the simulation; applying the workpiece weight and tool cutting force on the machine tool, performing static analysis, and obtaining the force and stress distribution results of the machine tool under the three-point support state through solution, so as to adjust and optimize the machine tool structure or support method to obtain the optimal solution.

[0006] Furthermore, the position of the shims on the machine tool bed is dynamically optimized to determine the shim position parameters, including:

[0007] Measure and mark the positions of the eight shims A, B, C, D, A', B', C', and D' on the bottom surface of the bed. Establish a coordinate system with the midpoint of the straight line AA' at the bottom of the bed as the origin O, and determine the coordinates of the eight shim positions and the coordinates of the actual center of gravity H of the machine tool under normal working conditions.

[0008] Construct the first approximate triangular region ADD' and the second approximate triangular region A'DD' based on the shim located at the apex; and construct the third triangular region EFG by taking the midpoint of the straight line DD' at the top of the bed bottom surface as point E, and determining points F and G between A'B' on both sides of the bottom end and between AB respectively; and construct the rectangular region PQRS centered on the centroid H.

[0009] In the three triangular regions, we analyze whether the center of gravity of the machine tool under harsh working conditions is within the rectangular region PQRS for each triangular region structure. In order to select the triangular region that can keep the center of gravity of the machine tool within the rectangular region PQRS under harsh working conditions, the vertex of the triangular region is used as the three support points of the pad position.

[0010] Furthermore, with the maximum first-order natural frequency and the minimum maximum deformation of the mating surface between the bed and the rotary table as objective functions, and the position of the shims as design variables, a multi-objective optimization design of the shim position is carried out.

[0011] Furthermore, the objective function for multi-objective optimization design is:

[0012] find G = (Y F X F (X G ), Y G Y E X E )

[0013] min = D & (-f1)

[0014] stG min ≤G≤G max

[0015] In the formula, G is the set of design variables; D is the maximum deformation at the joint surface between the bed and the rotary table; f1 is the first natural frequency of the bed structure; G min G max These are the lower and upper limits of the design variable, respectively; (X) F Y F Let (X) be the coordinates of point F, and (X) be the coordinates of point F. G Y G Let (X) be the coordinates of point G, and (X) be the coordinates of point G. E Y E Let E be the coordinates of point E.

[0016] Furthermore, the machine tool structure or support method is adjusted and optimized. The optimization principle is that the projection of the total center of mass of each component on the bottom surface of the bed is always within the triangular area enclosed by the three support points; and the area of ​​the triangle enclosed by the three support points is maximized.

[0017] Secondly, the technical solution adopted by the present invention is as follows: a three-point support structure based on the above-mentioned three-point support structure design method for a five-axis CNC machine tool, comprising: a machine tool bed, the front end of which adopts a rectangular structure and the rear end adopts a tapered body structure; and three shims, wherein the first and second shims are located on both sides of the bottom front end of the bed, and the third shim is located at the middle position of the rear end of the bed, forming a three-point support.

[0018] Furthermore, each shim is equipped with an adjusting screw or adjusting nut for adjusting the height of the shim.

[0019] Furthermore, the upper part of the bed is equipped with an X-axis bed guide rail, which is distributed in a stepped pattern with the front lower and the back higher.

[0020] Thirdly, the technical solution adopted by the present invention is: a computer-readable storage medium for storing one or more programs, wherein the one or more programs include instructions, which, when executed by a computing device, cause the computing device to perform any of the methods described above.

[0021] Fourthly, the technical solution adopted by the present invention is: a computing device comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs include instructions for performing any of the methods described above.

[0022] The present invention has the following advantages due to the adoption of the above technical solutions:

[0023] The three-point support of this invention utilizes the principle that three points define a plane, significantly improving the leveling and stability of the machine tool, and achieving higher machining accuracy while significantly shortening installation time. Furthermore, compared to multi-point support, the three-point support method offers better accuracy retention, lower internal stress, easier leveling, and simpler installation. Attached Figure Description

[0024] Figure 1 This is a flowchart of the design method for the three-point support structure in an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the eight-point support pad partition in an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the distribution of the three-point support pads in an embodiment of the present invention;

[0027] Figure 4a This is a schematic diagram of a conventional operating condition in an embodiment of the present invention;

[0028] Figure 4b This is a schematic diagram of harsh working conditions in an embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of the machine tool structure in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the bottom surface of the machine tool bed in an embodiment of the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0033] The machining accuracy and efficiency of a machine tool are determined by its overall static and dynamic characteristics, and the bed support method directly affects these characteristics. Shims, as crucial components connecting the foundation and the bed, significantly impact the machining accuracy of precision machine tools. Currently, the number and placement of shims are typically determined based on design experience, with shims usually evenly distributed across the bottom surface of the bed. Different shim arrangements result in varying static and dynamic characteristics of the bed during actual machining, thus affecting the machine tool's machining accuracy. A well-distributed shim arrangement can improve machining accuracy and extend the machine tool's lifespan.

[0034] In one embodiment of the present invention, a three-point support structure design method for a five-axis CNC machine tool is provided. In this embodiment, as... Figure 1 As shown, the method includes the following steps:

[0035] 1) Dynamically optimize the position of the shims on the machine tool bed and determine the shim position parameter information to improve the dynamic performance of the bed;

[0036] 2) Based on the position parameters of the shims and the working space of the machine tool, determine the three-point support position of the machine tool, and at the same time reduce the weight of the moving beam so that the projection of the total center of mass of each component on the bottom surface of the machine tool bed is always within the triangular area enclosed by the three-point support.

[0037] 3) Fixed support constraints are applied to the determined three-point support to restrict its direction of movement in the simulation, thereby simulating the real three-point support state and ensuring the accuracy of the simulation;

[0038] 4) Apply the weight of the workpiece and the cutting force of the tool to the machine tool, perform static analysis, and obtain the force and stress distribution of the machine tool under three-point support by solving the problem. This allows for the adjustment and optimization of the machine tool structure or support method to obtain the optimal solution.

[0039] In step 1) above, the position of the shims on the machine tool bed is dynamically optimized to determine the shim position parameter information, including the following steps:

[0040] 1.1) As Figure 2 As shown, measure and mark the positions of eight shims A, B, C, D, A', B', C', and D' on the bottom surface of the machine bed. Establish a coordinate system with the midpoint of the straight line AA' at the bottom of the machine bed as the origin O, and determine the coordinates of the eight shim positions and the coordinates of the actual center of gravity H of the machine tool under normal working conditions.

[0041] Since the positions of the shims on the machine tool bed are arranged according to the shape of the bottom surface of the bed, this embodiment is based on the existing eight support points for optimization design to determine the optimal three-point support structure.

[0042] 1.2) Construct the first approximate triangular region ADD' and the second approximate triangular region A'DD' based on the shims located at the apex; and construct the third triangular region EFG by taking the midpoint of the straight line DD' at the top of the bed bottom surface as point E, and determining points F and G between A'B' on both sides of the bottom end and between AB respectively; and construct the rectangular region PQRS centered on the centroid H, as shown. Figure 3 As shown;

[0043] Points F and G are determined between A'B' and AB on both sides of the bottom end, respectively. Specifically, in Ansys Workbench, a Solidworks model is imported, meshed, and material properties including density, Young's modulus, and Poisson's ratio are defined. Loads and motion constraints are added according to the actual working conditions of the machine tool, including applied forces and torques. Contact conditions, such as friction coefficient and contact type, are defined. The coordinates of F and G are added as design variables through the design variable module. An objective function module is added, defining the maximum deformation D and the first natural frequency. A constraint module is added, defining the lower and upper limits of the design variables. The optimization solver is run to search for the optimal design variables to optimize the objective function, thus determining the coordinates of design variables F and G. Static structural analysis results verify that the obtained coordinates of F and G meet the strength and stability requirements of the machine tool in actual operation.

[0044] Construct a rectangular region PQRS centered at the centroid H, specifically as follows:

[0045] In this embodiment, for example, the five-axis machine tool has a total height of 3300mm, a total length of 3300mm, and a total width of 2000mm. Under the condition that the rotational space of the AC axis is not considered at the extreme positions of the five-axis machine tool, refer to... Figure 4a and Figure 4b The maximum tool movement range of the machine tool is 1200mm in the Y-axis direction and 800mm in the X-axis direction. The maximum distances of the tool in the Y-axis direction at the two farthest extreme positions from the center of the rotary table are 475mm and 725mm, respectively. The extreme positions are defined as severe working conditions. In the Solidworks model, the projection of the actual center of gravity on the bottom surface when measuring the four severe working conditions are points P, Q, R, and S. Therefore, the rectangular area PQRS is set as the tolerance range of the machine tool's center of gravity.

[0046] In this embodiment, for example, a coordinate system is established with the midpoint of AA' as the origin, and the coordinates of each point are as follows: A(852, 0), A'(-852, 0), B(912, 720), B'(-912, 720), C(912, 1395), C'(-912, 1395), D(912, 2070), D'(-912, 2070), H(0, 957), with the unit being mm.

[0047] 1.3) In the three triangular regions, analyze whether the center of gravity of the machine tool under harsh working conditions is within the rectangular region PQRS for each triangular region structure, so as to select the triangular region that can keep the center of gravity of the machine tool within the rectangular region PQRS under harsh working conditions, and use the vertex of the triangular region as the three support points of the pad position.

[0048] Among them, such as Figure 4a , Figure 4bAs shown, considering the normal and severe working conditions of the machine tool, the severe working condition of the machine tool is as follows: when the spindle feeds to the bottom of the stroke in the Z direction, when the moving beam moves to the front of the stroke, and when the spindle head moves to the end of the two strokes in the Y direction.

[0049] In this embodiment, the three vertices of the third triangular region EFG were determined as the positions of the pads, as shown in Table 1.

[0050] Table 1. Coordinates of the three support points of the shim.

[0051] Shims Location (X, Y) E <![CDATA[(X E ,AND E )]]> F <![CDATA[(X F ,AND F )]]> G <![CDATA[(X G ,AND G )]]>

[0052] In step 1.3) above, the dynamic optimization criteria are: increase the natural frequencies of each order; distribute the natural frequencies as evenly as possible; avoid resonance caused by the natural frequencies being the same as the external excitation frequencies; and ensure that the dynamic stiffness of each substructure does not have obvious weak points.

[0053] Therefore, in this embodiment, the objective functions are the maximum first-order natural frequency and the minimum maximum deformation of the mating surface between the bed and the turntable, and the position of the shim is used as the design variable to perform multi-objective optimization design on the position of the shim.

[0054] Among them, optimizing the first-order natural frequency is used to improve the dynamic performance of the bed, and optimizing the maximum deformation at the interface between the bed and the turntable is used to improve the static performance of the bed.

[0055] In this embodiment, the objective function of the multi-objective optimization design is:

[0056] find G = (Y F X F (X G ), Y G Y E X E )

[0057] min = D & (-f1)

[0058] stG min ≤G≤G max

[0059] In the formula, G is the set of design variables; D is the maximum deformation at the joint surface between the bed and the turntable; f1 is the first natural frequency of the bed structure, and the specific values ​​used in this embodiment are shown in Table 3; G min G max These represent the lower and upper limits of the design variables, respectively. The specific values ​​used in this embodiment are shown in Table 2. (X) F Y F Let (X) be the coordinates of point F, and (X) be the coordinates of point F. G Y G Let (X) be the coordinates of point G, and (X) be the coordinates of point G. E YE Let E be the coordinates of point E.

[0060] Table 2. Range of values ​​for design variables

[0061]

[0062] In this embodiment, as shown in Tables 1 and 2, according to the above processing, if A, A', D or A, D, D' is used as the basis for the three-point support of the machine tool, then the centers of gravity J (-30, 1035) and K (30, 1035) in both cases are not within the range of region PQSR, and stable operation under harsh working conditions cannot be guaranteed. The midpoint of D-D' is selected as E. Based on the machine tool workspace, three-point supports E (0, 2070), F (871, 220), and G (-871, 220) are constructed, forming the third triangular region, namely X. E =30, Y E =2070, X F =|X G |=871,Y F =Y G =220. At this time, the actual center of gravity of the machine tool under normal working conditions is H', which is within the rectangular area PQRS. By reducing the weight of the moving beam, the center of gravity area of ​​the three-point supported machine tool under adverse working conditions can be included within the actual center of gravity area of ​​the eight-point supported machine tool under adverse working conditions, so that the machine tool has sufficient rigidity and strength.

[0063] The harsh working conditions of the machine tool during operation are measured using a 3D model. The actual centers of gravity are denoted as P, Q, S, and R, and the enclosed quadrilateral area represents the actual projection range of the machine tool's center of gravity during operation. In the coordinate system described above, the coordinates of each point are: P(-18, 1076), Q(25, 1076), S(25, 874), R(-18, 874).

[0064] In step 3) above, finite element simulation is used to establish a three-dimensional model including the machine tool body, support structure and three support points.

[0065] In step 3) above, the three-point support is constrained, that is: in the finite element model, the bottom surfaces of the three foot pads are set as fixed supports, which restricts all translational and rotational degrees of freedom of the foot pads and the bed, so that the constrained parts cannot undergo any displacement or rotation during the analysis process.

[0066] In step 4) above, the machine tool structure or support method is adjusted and optimized. The optimization principle is that the projection of the total center of mass of each component on the bottom surface of the bed is within the triangular area enclosed by the three support points; and the area of ​​the triangle enclosed by the three support points is the largest.

[0067] In this embodiment, static analysis is performed to obtain the force and stress distribution of the machine tool under three-point support. These results are used to evaluate the machine tool's strength and stress condition; based on the Ansys analysis results, the machine tool's strength and accuracy under three-point support are evaluated. The stress distribution, deformation, and stress conditions at the support points of each part of the machine tool are analyzed. Based on the analysis results, the machine tool structure or support method is adjusted and optimized to improve the machine tool's strength and accuracy. The optimal solution is selected by repeatedly analyzing and comparing different design schemes.

[0068] Table 3 Comparison of the first six natural frequencies of the bed before and after optimization (unit: Hz)

[0069]

[0070] As shown in Table 3, the first-order mode has the greatest impact on the machine tool's vibration in the modal analysis results. The first-order mode is characterized by the machine tool swaying left and right, with the upper part swaying more noticeably. Therefore, it can be inferred that the joint surface between the moving beam and the column is the weak point. This is because the joint surface between the bed and the moving beam, and between the moving beam and the column, has weak rigidity, the bed structure layout is unreasonable, and the moving beam is too heavy, resulting in a high center of gravity for the machine tool. This weakness will cause a low first-order vibration frequency. The low stiffness of the bed support feet may also be one of the reasons for the low frequency. To address this issue, this embodiment adopts measures such as increasing the stiffness of the joint surface between the moving beam and the column, reducing the weight of the moving beam, and designing a more reasonable bed structure layout. With three-point support, the stiffness of the foot support needs to be strengthened. In the second to fifth-order modes, the most prominent feature of the mode is the up-and-down and left-and-right swaying of the spindle box around the Y-guide rail. This indicates insufficient stiffness at the connection between the spindle box and the Y-guide rail, requiring further structural improvements and weight reduction. In the sixth mode, the mode shape shows that the spindle box swings up and down around the Y-guide rail and the entire machine bed swings up and down with a large amplitude. Further optimization can be achieved by strengthening the stiffness of the three-point support, adjusting and finding the optimal position of the three-point support, and increasing the stiffness by improving the structure of the machine bed.

[0071] In summary, the machine bed is a fundamental component of a machine tool, requiring sufficiently high static and dynamic stiffness and precision retention. After adjusting the position of the shims, using titanium alloy materials for some components, reducing the mass of the moving beam, and optimizing the machine bed structure, the first six natural frequencies of the machine bed were all improved, achieving the effect of optimizing the static and dynamic characteristics of the machine bed.

[0072] The method for determining the three-point support position of a machine tool according to the present invention optimizes the dynamic and static characteristics of the machine tool bed. Therefore, it can improve the accuracy and stability of the machine tool and extend its service life. Because it can improve the dynamic and static characteristics of the machine tool without changing its structure, by optimizing the position of the shims, reducing the mass of the moving beam, and using higher-strength materials, it demonstrates application value in the actual design of machine tools. It can improve the machining accuracy of the machine tool, and the three-point support method has good accuracy retention, is easy to level, and facilitates installation.

[0073] In one embodiment of the present invention, a three-point support structure for a machine tool is provided, which is configured according to the setting method provided in the above embodiments. In this embodiment, as... Figure 5 , Figure 6 As shown, the three-point support structure includes:

[0074] The machine tool bed 1 has a rectangular structure at the front end and a tapered body structure at the rear end;

[0075] The pad 2 is set in three pieces. The first and second pads 2 are located on the front bottom sides of the bed frame 1, and the third pad 2 is located at the middle of the rear end of the bed frame 1, forming a three-point support.

[0076] In the above embodiment, each shim 1 is equipped with an adjusting component 3 for adjusting the height of the shim, which is a screw or adjusting nut. In use, the height of the shim can be adjusted by rotating the screw or nut on the adjusting shim to keep the machine tool level. Adjustments should typically be made point by point to ensure the machine tool is stable and balanced.

[0077] In the above embodiments, an X-axis bed guide rail is provided on the upper part of the bed, and the X-axis bed guide rail is distributed in a stepped shape with a lower front and a higher rear. This invention employs three-point support, simplifying machine tool adjustment, eliminating reliance on a foundation, and ensuring accuracy and stability. The stepped distribution of the X-axis bed guide rail, with a lower front and a higher rear, can significantly reduce the weight of the moving component column while ensuring Z-axis strength, thereby achieving higher acceleration performance.

[0078] In summary, the three-point support structure for the machine bed is commonly used in machine tools, large mechanical equipment, and other applications requiring stable support. The three-point support structure effectively distributes loads, reduces vibration, and improves equipment stability and accuracy. Machine tool leveling has a significant impact on the stability and accuracy of machining; improper leveling will lead to machine tool vibration, unstable machining quality, and shortened equipment lifespan. Traditional anchor bolts fixing the machine bed to the ground create numerous contact points, which is detrimental to machine tool leveling.

[0079] Existing machine tool bed support methods mostly adopt eight-point support or six-point support. This invention, through design and optimization, achieves a three-point support method for the bed. The three-point support utilizes the principle that three points determine one surface, which facilitates machine tool leveling, stabilizes the machine tool on the ground, improves machine tool stability, saves installation costs, and shortens the installation cycle.

[0080] The arrangement and adjustment of the shims should be carried out according to the specific machine tool design and support point positions to ensure that the machine tool can be stably supported on three points, thereby guaranteeing machining accuracy and safety. The three support points should be distributed as evenly as possible on the bottom of the machine tool to ensure stable support and good contact between the support points and the ground. This avoids machine tool shaking or instability caused by improper support point positions. The stability of the support points should be checked regularly to prevent loosening or damage from affecting the stability of the machine tool. When moving or repositioning the machine tool, the support points should be readjusted to ensure that the machine tool continues to maintain a three-point support state.

[0081] Before installing the machine tool, ensure that the ground on which the machine tool is placed is level. If the ground is tilted or uneven, it may affect the stability of the machine tool. Therefore, it is necessary to level the ground beforehand.

[0082] Place adjusting shims under the support points to adjust their height, ensuring the machine tool is horizontally balanced when supported by three points. The height of the shims can be adjusted by rotating the screws or nuts on them to keep the machine tool level. Adjustments should typically be made point by point to ensure the machine tool is stable and balanced.

[0083] This invention reduces the mass of the moving beam through optimized structural design, thereby keeping the machine tool's actual center of gravity within a reasonable range under harsh working conditions. This serves as a crucial basis for achieving three-point support. This technical solution improves the machine tool's stability and accuracy, makes it more flexible during rapid adjustments, and provides a more reliable guarantee for production.

[0084] In one embodiment of the present invention, a computing device is provided. This computing device can be a terminal and may include a processor, a communication interface, memory, a display screen, and an input device. The processor, communication interface, and memory communicate with each other via a communication bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. When the computer programs are executed by the processor, they implement the methods described in the above embodiments. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface is used for wired or wireless communication with external terminals. Wireless communication can be achieved through Wi-Fi, a management network, NFC (Near Field Communication), or other technologies. The display screen can be a liquid crystal display (LCD) or an e-ink display. The input device can be a touch layer covering the display screen, or buttons, a trackball, or a touchpad mounted on the casing of the computing device, or an external keyboard, touchpad, or mouse. The processor can call logical instructions stored in the memory.

[0085] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0086] In one embodiment of the present invention, a computer program product is provided, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to perform the methods provided in the above-described method embodiments.

[0087] In one embodiment of the present invention, a non-transitory computer-readable storage medium is provided, which stores server instructions that cause a computer to perform the methods provided in the above embodiments.

[0088] The computer-readable storage medium provided in the above embodiments has a similar implementation principle and technical effect to the above method embodiments, and will not be described again here.

[0089] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A design method for a three-point support structure of a five-axis CNC machine tool, characterized in that, include: The position of the shims on the machine tool bed is dynamically optimized to determine the shim position parameters and improve the dynamic performance of the bed. Based on the position parameters of the shims and the working space of the machine tool, the three-point support positions of the machine tool are determined. At the same time, the weight of the moving beam is reduced so that the projection of the total center of mass of each component on the bottom surface of the machine tool bed is always within the triangular area enclosed by the three-point support. For the three-point support, namely the contact surface between the bottom surface of the anchor pad and the ground, a fixed support constraint is applied to restrict all degrees of freedom in the simulation, thereby simulating the real three-point support state and ensuring the accuracy of the simulation. Apply the weight of the workpiece and the cutting force of the tool to the machine tool, perform static analysis, and obtain the force and stress distribution of the machine tool under three-point support state through solution, so as to adjust and optimize the machine tool structure or support method and obtain the optimal solution; The position of the shims on the machine tool bed is dynamically optimized to determine the shim position parameters, including: Measure and mark the positions of the eight shims A, B, C, D, A', B', C', and D' on the bottom surface of the bed. Establish a coordinate system with the midpoint of the straight line AA' at the bottom of the bed as the origin O, and determine the coordinates of the eight shim positions and the coordinates of the actual center of gravity H of the machine tool under normal working conditions. Based on the shims located at the apex, construct the first approximate triangular region ADD' and the second approximate triangular region A'DD'; and construct the third triangular region EFG by taking the midpoint of the straight line DD' at the top of the bottom surface of the bed as point E, and determining points F and G between A'B' on both sides of the bottom end and between AB respectively; and the rectangular region PQRS centered on the center of gravity H: Based on the dimensions of the five-axis machine tool, under the condition that the rotation space of the AC axis is not considered in the extreme positions of the five-axis machine tool, determine the maximum range of movement of the machine tool in the Y-axis direction and the range of movement in the X-axis direction; and determine the two extreme distances in the Y-axis direction for the tool at the two farthest extreme positions from the center of the rotary table; define the extreme positions as severe working conditions, and in the Solidworks model, measure the projection of the actual center of gravity on the bottom surface as points P, Q, R, and S when the tool is in four severe working conditions; In the three triangular regions, we analyze whether the center of gravity of the machine tool under harsh working conditions is within the rectangular region PQRS for each triangular region structure. In order to select the triangular region that can keep the center of gravity of the machine tool within the rectangular region PQRS under harsh working conditions, the vertex of the triangular region is used as the three support points of the pad position. Adjustments and optimizations are made to the machine tool structure or support method. The optimization principle is that the projection of the total center of mass of each component on the bottom surface of the bed is always within the triangular area enclosed by the three support points; and the area of ​​the triangle enclosed by the three support points is maximized.

2. The three-point support structure design method for a five-axis CNC machine tool as described in claim 1, characterized in that, Using the maximum first-order natural frequency and the minimum maximum deformation of the mating surface between the bed and the rotary table as objective functions, and the position of the shims as design variables, a multi-objective optimization design is performed on the shim position.

3. The three-point support structure design method for a five-axis CNC machine tool as described in claim 2, characterized in that, The objective function for multi-objective optimization design is: ； In the formula, G is the set of design variables; D is the maximum deformation at the joint surface between the bed and the rotary table. The first natural frequency of the bed structure; These are the lower and upper limits of the design variables, respectively; Let F be the coordinates. Let G be the coordinates. Let E be the coordinates of point E.

4. A three-point support structure based on the three-point support structure design method for a five-axis CNC machine tool as described in any one of claims 1 to 3, characterized in that, include: The machine tool bed has a rectangular structure at the front end and a tapered structure at the rear end; The bed frame is made of three pads. The first and second pads are located on the front bottom sides of the bed frame, and the third pad is located in the middle of the rear end of the bed frame, forming a three-point support.

5. The three-point support structure as described in claim 4, characterized in that, Each shim is equipped with an adjusting screw or adjusting nut for adjusting the height of the shim.

6. The three-point support structure as described in claim 4, characterized in that, The upper part of the bed is equipped with an X-axis bed guide rail, which is distributed in a stepped pattern with the front lower and the back higher.

7. A computer-readable storage medium for storing one or more programs, characterized in that, The one or more programs include instructions that, when executed by a computing device, cause the computing device to perform any of the methods described in claims 1 to 3.

8. A computing device, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for performing any of the methods described in claims 1 to 3.

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