Manufacturing methods for machine tool components

Abstract

To provide a method for manufacturing a component of a machine tool, which allows shape optimization to be conducted with higher accuracy for a component including a constituent that varies during use of a machine tool.SOLUTION: A method for manufacturing a component of a machine tool includes a stress analysis step S3 and an optimization step S4. In the stress analysis step S3, stress analysis is conducted based on a constituent that varies in a component. In the optimization step S4, an optimized shape of the component is determined by applying topology optimization processing, in accordance with a result of the stress analysis step S3.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a method for manufacturing mechanical components of a machine tool.

Background Art

[0002] In order to improve the machining accuracy of a machine tool, high rigidity is required for the components of the machine tool. However, when the rigidity is increased, the components will conversely become heavier. Various methods for optimizing the trade-off relationship between rigidity and mass have been studied. For example, Patent Document 1 discloses a configuration for optimizing the shape of components using a topology optimization method.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the configuration disclosed in Patent Document 1 does not consider at all the case where there are elements that vary in the components of the machine tool during its use. Therefore, when there are elements that vary in the components of the machine tool during its use, the shape of the components optimized using the topology optimization method disclosed in Patent Document 1 may not necessarily be an optimized one, and there is room for improvement.

[0005] The present invention has been made in view of such problems, and aims to provide a method for manufacturing mechanical components of a machine tool that can more accurately optimize the shape of components having elements that vary during the use of the machine tool.

Means for Solving the Problems

[0006] One aspect of the present invention is a method for manufacturing components of a machine tool, The above components In a first state where the load of the moving mechanism is applied to the first position when the moving mechanism attached to the component is in the first position, and in a second state where the load of the moving mechanism is applied to the second position when the moving mechanism is in a second position different from the first position in the component, A stress analysis process for performing stress analysis on the above-mentioned components, The above stress analysis process The results of the stress analysis in the first state and the results of the stress analysis in the second state The present invention relates to a method for manufacturing components of a machine tool, which includes an optimization step of determining the optimized shape of the above-mentioned components by performing topology optimization processing based on the above-mentioned parameters. [Effects of the Invention]

[0007] According to one embodiment described above, stress analysis is performed on the components of a machine tool based on fluctuating elements, and then topology optimization is performed based on the results of the stress analysis to determine the optimal shape of the components. As a result, the optimized shape of the components takes into account the fluctuating elements in the components, and therefore the shape of components including fluctuating elements can be optimized with higher precision. Furthermore, since the optimization is performed by topology optimization, the optimization process can be completed in a short amount of time.

[0008] As described above, according to the above embodiment, it is possible to provide a method for manufacturing components of a machine tool that enables more precise optimization of the shape of components having elements that change during the use of the machine tool. [Brief explanation of the drawing]

[0009] [Figure 1] Rear perspective view of the machine tool and workpiece in Embodiment 1. [Figure 2] (a) Front view of the machine tool and workpiece in the first state, (b) Front view of the machine tool and workpiece in the second state, and (c) Front view of the machine tool and workpiece in the third state in Embodiment 1. [Figure 3] (a) Front view of the machine tool and workpiece in the fourth state, (b) Front view of the machine tool and workpiece in the fifth state, and (c) Front view of the machine tool and workpiece in the sixth state in Embodiment 1. [Figure 4] A block diagram of a manufacturing apparatus for machine tool components in Embodiment 1. [Figure 5] Flowchart of the manufacturing method in Embodiment 1. [Figure 6] (a) Front side perspective view of the solid beam model in Embodiment 1, (b) Rear side perspective view of the solid beam model. [Figure 7] (a) Front and rear contour diagrams of the beam in the first state, (b) Front and rear contour diagrams of the beam in the second state, and (c) Front and rear contour diagrams of the beam in the third state. [Figure 8] (a) Front and rear contour diagrams of the beam in the fourth state, (b) Front and rear contour diagrams of the beam in the fifth state, and (c) Front and rear contour diagrams of the beam in the sixth state in Embodiment 1. [Figure 9] (a) Optimized beam shape in Embodiment 1, (b) Beam shape in the comparative form. [Modes for carrying out the invention]

[0010] (Embodiment 1) Embodiment 1 relating to the manufacturing method of the components of the above-mentioned machine tool will be described with reference to Figures 1 to 9. Embodiment 1 is a method for manufacturing a beam 10, which is a component of the machine tool 1 shown in Figure 1.

[0011] 1-1. Workpiece W The workpiece W of the machine tool 1 is not limited, but in this embodiment 1, as shown in Figure 1, the workpiece W is a cubic member. The workpiece W can have a mass of, for example, 20,000 to 30,000 kg.

[0012] 1-2. Machine tool 1 As shown in FIG. 1, the machine tool 1 includes a beam 10, a left unit 20, a right unit 30, a left support column 41, a right support column 42, and a central support column 43. The outer shape of the beam 10 is substantially rod-shaped. In Embodiment 1, the longitudinal direction of the beam 10 is the X direction, the gravitational direction which is the height direction of the beam 10 is the Y direction, and the direction orthogonal to the X direction and the Y direction which is the thickness direction of the beam 10 is the Z direction. As shown in FIG. 2(a), the left support column 41 is attached to the lower left side of the beam 10, and the right support column 42 is attached to the lower right side. Further, as shown in FIG. 1, the central support column 43 is attached to the center of the back surface of the beam 10. The beam 10 is supported by the respective support columns 41 to 43.

[0013] Also, as shown in FIG. 2(a), as a moving mechanism, the left unit 20 is attached to the front right side of the beam 10, and the right unit 30 is provided on the front left side. The left unit 20 and the right unit 30 are attached so as to be movable in the X direction via rails 21 and 31 provided on the front surface of the beam 10. The positions of the left unit 20 and the right unit 30 in the X direction are controlled by a control device not shown.

[0014] Also, a predetermined tool for machining the workpiece W is provided in the left unit 20 and the right unit 30. The left unit 20 is configured to move from the initial position shown in FIG. 2(a) to the upper position of the workpiece W as shown in FIGS. 2(b) and (c) and perform predetermined machining on the workpiece W. Further, the right unit 30 is configured to move from the initial position shown in FIG. 3(a) to the upper position of the workpiece W as shown in FIGS. 3(b) and (c) and perform predetermined machining on the workpiece W. In FIGS. 2(a) and 3(a), both the left unit 20 and the right unit 30 are in the initial positions, showing the same state.

[0015] In the first embodiment, the left unit 20 and the right unit 30 are large-sized. The mass of the left unit 20 is approximately 20,000 kg, and the mass of the right unit 30 is approximately 15,000 kg. And the beam 10 functions as a beam that supports the left unit 20 and the right unit 30 moving in the X direction. Therefore, when the left unit 20 and the right unit 30 move in the X direction, accordingly, the position where the load is applied to the beam 10 changes. Specifically, as shown in FIGS. 2(a) to (c) and FIGS. 3(a) to (c), the center-of-gravity position Ga of the left unit 20 and the center-of-gravity position Gb of the right unit change according to their respective states.

[0016] 1-3. Manufacturing apparatus 100 for components of machine tool 1 Next, the manufacturing apparatus 100 for components of the machine tool 1 will be described. As shown in FIG. 4, the manufacturing apparatus 100 for components of the machine tool 1 includes a stress analysis unit 101, an optimization processing unit 102, a determination unit 103, and a component creation unit 104.

[0017] The stress analysis unit 101 performs stress analysis on the shape model of the component. The stress analysis is performed based on the elements that vary in the component. The elements that vary in the component are not limited, and examples include the position of the load applied to the component that varies according to the position state of the moving mechanism attached to the component, the temperature change of the component, etc. In the first embodiment, as the element that varies in the component, the position of the load applied to the beam 10 that varies according to the position state of the left unit 20 and the right unit 30, which are the moving mechanisms in the beam 10 as the component, is adopted. Note that the stress analysis unit 101 can be configured by a computer that executes a predetermined program.

[0018] The optimization processing unit 102 performs topology optimization processing. The objective variables and constraints in the topology optimization processing can be appropriately set according to the components of the machine tool 1 to be optimized. For example, the objective variables may include minimizing at least one of the displacement and mass of the components. The compliance (reciprocal of stiffness) of the components may be derived based on the displacement at multiple positions, and this compliance may be included as an objective variable. Furthermore, the constraints in the topology optimization processing may include the mass of the components, or alternatively, there may be no constraints. The optimization processing unit 102 can be configured as a computer that executes a predetermined program.

[0019] The determination unit 103 determines whether the shape model created as a result of processing by the optimization processing unit 102 satisfies the set target value. Based on the determination result by the determination unit 103, stress analysis can be performed again. In other words, by repeatedly performing stress analysis by the stress analysis unit 101 and topology optimization processing by the optimization processing unit 102, the optimized shape can be determined with high accuracy. The determination unit 103 can be configured as a computer that executes a predetermined program.

[0020] The component creation unit 104 creates components based on the optimized shape determined by the determination unit 103 to satisfy the target value. The configuration of the component creation unit 104 is not limited and can be configured using a predetermined machine tool.

[0021] 1-4. Optimization and manufacturing of the beam 10 shape Next, the optimization and manufacturing of the beam 10 shape will be explained according to the flowchart in Figure 5. First, in step S1 of Figure 5, the initial shape of the beam 10 is set. In this embodiment 1, the back surface and both surfaces in the X direction of the beam 10 are not changed during the optimization process, and a solid component, which is a solid model as shown in Figures 6(a) and (b), is adopted as the initial shape of the beam 10.

[0022] Next, in step S2 of Figure 5, the objective variable, constraints, and target values ​​for the topology optimization process are set. In this embodiment 1, the objective variables are set to minimize the displacement and mass of the beam 10, and the constraints are set to none. The target values ​​are set to be that the displacement in the Y direction of the beam 10 is less than or equal to a predetermined value, and that the mass of the beam 10 is 30,000 kg or less.

[0023] Subsequently, in step S3, the stress analysis unit 101 performs a stress analysis process to perform stress analysis on the initial shape of the beam 10. In this embodiment 1, stress analysis is performed for a first state in which the left unit 20 is in the initial position shown in Figure 2(a), a second state in which it has moved a predetermined distance to the right in the X direction as shown in Figure 2(b), and a third state in which it has moved further to the right in the X direction to the terminal position as shown in Figure 2(c). Furthermore, stress analysis is performed for a fourth state in which the right unit 30 is in the initial position shown in Figure 3(a), a fifth state in which it has moved a predetermined distance to the left in the X direction as shown in Figure 3(b), and a sixth state in which it has moved further to the left in the X direction to the terminal position as shown in Figure 3(c).

[0024] In this embodiment 1, the element that fluctuates in the beam 10 is the position of the load that fluctuates according to the positional state of the left unit 20 and the right unit 30 in the beam 10. The positions of the fluctuating load in the first to third states shown in Figures 2(a) to (c) and the fourth to sixth states shown in Figures 3(a) to (c) are the center of gravity position Ga of the left unit 20 and the center of gravity position Gb of the right unit 30 in each state.

[0025] As a result of the stress analysis performed by the stress analysis unit 101, the contour plots for the first, second, and third states are shown in Figures 7(a), 7(b), and 7(c), respectively, and the contour plots for the fourth, fifth, and sixth states are shown in Figures 8(a), 8(b), and 8(c), respectively. As shown in Figures 7(a) to (c) and 8(a) to (c), there is a bias in the position of the loads G1 to G3 applied to the beam 10 as the left unit 20 and the right unit 30 move, resulting in a change in the stress distribution as a result of the stress analysis. The results of the stress analysis performed by the stress analysis unit 101 are acquired as 3D data along the 3D shape of the beam 10, and Figures 7 and 8 show representative 2D contour plots as part of the stress analysis results of this 3D data.

[0026] Subsequently, in step S4, the optimization processing unit 102 performs topology optimization processing based on the stress analysis results from the stress analysis unit 101. Then, in step S5, the determination unit 103 determines whether the shape created by the topology optimization processing satisfies the target value. If the determination unit 103 determines that the target value is not met, the process proceeds to step S5 No., and in step S3, stress analysis is performed on the shape created by the topology optimization processing, and the subsequent steps are repeated.

[0027] On the other hand, if the determination unit 103 determines in step S5 that the target value is met, the process proceeds to Yes in step S5, and in step S6, the shape created by the topology optimization process is determined as the optimized shape of the beam 10. In this embodiment 1, as shown in Figure 9(a), the optimized shape of the beam 10 has multiple ribs 11 provided in the high-stress region, which is a region where the stress generated inside the beam 10 is relatively high, and no ribs 11 are provided in the low-stress region, which is a region where the stress generated is relatively low. Note that the multiple ribs 11 may include some with different shapes from each other in order to ensure the necessary rigidity.

[0028] Subsequently, in step S7, the component creation unit 104 performs a creation process S7 to create the beam 10 based on the optimized shape shown in Figure 9(a), and the flow is completed.

[0029] 1-5. Confirmation Test A comparison of the mass of the beam 10 of Embodiment 1, which has the optimized shape shown in Figure 9(a), and the comparative beam 90 shown in Figure 9(b) was performed. The comparative beam 90 has ribs 91 arranged inside at a fixed rate in predetermined repeating units, as shown in Figure 9(b).

[0030] When comparing the beam 10 of Embodiment 1 with the comparative beam 90, it was confirmed that both had equivalent strength, and the mass of the beam 10 of Embodiment 1 was reduced by approximately 25% compared to the mass of the comparative beam 90.

[0031] 1-6. Effects According to this embodiment 1, stress analysis is performed based on the fluctuating elements in the components, and then topology optimization is performed based on the results of the stress analysis to determine the optimal shape of the beam 10. As a result, the optimized shape of the beam 10 takes into account the fluctuating elements of the beam 10, so that optimization can be performed with higher accuracy for beams 10 that have fluctuating elements. Furthermore, since the optimization is performed by topology optimization, the optimization process can be completed in a short amount of time.

[0032] Furthermore, this embodiment 1 includes a manufacturing step S7 in which the beam 10 is created based on the optimized shape created in the optimization step S4. This makes it possible to obtain a beam 10 having the optimized shape.

[0033] Furthermore, in this embodiment 1, the elements that fluctuate in the components include the load applied to the beam, which fluctuates according to the positional state of the two movable units 20 and 30 attached to the beam 10. This makes it possible to optimize the beam 10, which is equipped with the two movable units 20 and 30, with higher precision.

[0034] Furthermore, in the optimization process S4, the objective variables in the topology optimization process include minimizing the displacement of the beam 10 and minimizing at least one of its masses, and in this embodiment 1, both are included. This makes it possible to optimize the displacement and mass of the beam 10, which are in a trade-off relationship.

[0035] As described above, according to this embodiment 1, the shape optimization of the beam 10 having fluctuating elements can be performed with higher precision.

[0036] In this embodiment 1, the constraints for the topology optimization process in optimization step S4 were set to none, but this is not limited to this, and any desired constraints may be set.

[0037] The present invention is not limited to the embodiments described above, and can be applied to various embodiments without departing from its spirit. The components 10 of the machine tool 1 are not limited to those shown in Embodiment 1. For example, the machine tool 1 can be a machining center, a vertical grinding machine, a cylindrical grinding machine, a surface grinding machine, a center grinding machine, an internal diameter grinding machine, etc., and the components 10 can be various components of these machine tools. [Explanation of Symbols]

[0038] 1...Machine tool, 10...Beam (component), 11...Rib, 12...Mounting part, 20...Left unit (moving mechanism), 30...Right unit (moving mechanism)

Claims

1. A method for manufacturing components of a machine tool, A stress analysis step is performed to perform stress analysis on the component in a first state in which the load of the moving mechanism is applied to the first position when the moving mechanism attached to the component is in the first position on the component, and in a second state in which the load of the moving mechanism is applied to the second position when the moving mechanism is in a second position different from the first position on the component. A method for manufacturing a component of a machine tool, comprising: an optimization step of performing a topology optimization process to determine the optimized shape of the component based on the results of the stress analysis of the first state and the results of the stress analysis of the second state in the stress analysis step described above.

2. A method for manufacturing a component of a machine tool according to claim 1, comprising a manufacturing step of creating the component based on the optimized shape created in the optimization step described above.

3. A method for manufacturing a component of a machine tool according to claim 1 or 2, wherein the objective variable in the topology optimization process described above includes minimizing at least one of the displacement and mass of the component.

4. A method for manufacturing a component of a machine tool according to claim 3, wherein the constraints in the topology optimization process described above include the mass of the component.

Images