Design method and system of an internally cooled cutting tool

Abstract

The application discloses a design method and system of an inner cooling tool, and the method comprises the following steps: decomposing the structural parameters of the inner cooling hole; the structural parameters at least include the diameter of the inner cooling hole, the spacing of the inner cooling hole and the angle of the inner cooling hole; designing an orthogonal experiment scheme according to the decomposed structural parameters of the inner cooling hole to obtain the deformation of the inner cooling tool; finding out the significant factors affecting the structural strength of the inner cooling tool, the influence degree of the significant factors and the non-significant factors from the structural parameters of the inner cooling hole based on the deformation of the inner cooling tool; and designing the inner cooling tool according to the significant factors, the influence degree of the significant factors and the non-significant factors. The orthogonal analysis method is adopted to find out the significant factors affecting the structural strength of the inner cooling tool from the structural parameters of the inner cooling hole; the structural design of the inner cooling tool is optimized according to the significant factors affecting the structural strength of the inner cooling tool, and the design scheme with the minimum reduction of the structural strength of the inner cooling tool is obtained under the condition of meeting the flow requirement of the cutting fluid.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cutters, in particular to a design method and system of an internal cooling cutter. BACKGROUND

[0002] High-speed milling has the advantages of small cutting force, high cutting efficiency and high-quality machined surface. Cooling is very important in high-speed milling. Traditional spray cutting uses a large amount of cutting fluid, which seriously threatens the health of workers, and the disposal of mixed cutting waste liquid also becomes an environmental problem that plagues enterprises. Traditional spray cutting has been on the verge of being eliminated, and internal cooling cutters with little or no cutting fluid are gradually gaining attention from users.

[0003] Currently, there are the following problems in the design of internal cooling cutters:

[0004] 1. Adding internal cooling holes to the traditional milling cutter bar will reduce the strength of the cutter, and there is currently a lack of relevant design methods to minimize the reduction in strength.

[0005] 2. There is a lack of characterization methods for the influence of internal cooling holes on the strength of the cutter. SUMMARY

[0006] The main purpose of the present application is to provide a design method and system of an internal cooling cutter, which uses orthogonal analysis to find out the significant factors affecting the structural strength of the internal cooling cutter from the structural parameters of the internal cooling hole; according to the significant factors affecting the structural strength of the internal cooling cutter, the internal cooling cutter structural design is optimized, and under the condition of meeting the cutting fluid flow requirement, the design scheme that minimizes the reduction of the internal cooling cutter structural strength is obtained.

[0007] The present application adopts the following technical solutions:

[0008] On the one hand, a design method of an internal cooling cutter, comprising:

[0009] decomposing the structural parameters of the internal cooling hole; the structural parameters at least include the internal cooling hole diameter, the internal cooling hole spacing and the internal cooling hole angle;

[0010] designing an orthogonal experiment scheme according to the decomposed structural parameters of the internal cooling hole to obtain the deformation of the internal cooling cutter;

[0011] based on the deformation of the internal cooling cutter, finding out the significant factors affecting the structural strength of the internal cooling cutter, the influence degree of the significant factors and the non-significant factors from the structural parameters of the internal cooling hole;

[0012] designing the internal cooling cutter according to the significant factors, the influence degree of the significant factors and the non-significant factors.

[0013] Preferably, before decomposing the structural parameters of the internal cooling hole, it further comprises,

[0014] According to the inner cooling hole structure of the inner cooling tool, structural analysis is performed;

[0015] The structural parameters of the inner cooling hole are decomposed, specifically including:

[0016] The structural parameters of the inner cooling hole are decomposed based on the structural analysis.

[0017] Preferably, an orthogonal experiment scheme is designed according to the decomposed structural parameters of the inner cooling hole, and the deformation of the inner cooling tool is obtained, specifically including:

[0018] According to the number of decomposed structural parameters of the inner cooling hole, an simulation experiment scheme is designed by using orthogonal analysis method, the structural parameters are designed by using equal division, the radial cutting force borne by the inner cooling tool is simulated by using three-dimensional finite element software, the inner cooling tool model is simulated, and the deformation of the inner cooling tool is obtained.

[0019] Preferably, based on the deformation of the inner cooling tool, the significant factors affecting the structural strength of the inner cooling tool, the influence degree of the significant factors and the non-significant factors are found out from the structural parameters of the inner cooling hole, specifically including:

[0020] Based on the deformation of the inner cooling tool, the significant factors affecting the structural strength of the inner cooling tool, the influence degree of the significant factors and the non-significant factors are found out from the structural parameters of the inner cooling hole, specifically including:

[0021] According to the deformation of the inner cooling tool, F and F 表 are obtained by using F test method, and based on F and F 表 the significant factor i, the influence degree of the significant factor i and the non-significant factor x are found out from the structural parameters of the inner cooling hole; i∈1,2,3..., x∈1,2,3..., and the calculation formula of the influence degree of each structural parameter is as follows:

[0022] α=F-F 表

[0023] Wherein, F is calculated according to experimental data; F 表 is obtained by looking up table; the structural parameter with α>0 is a significant factor, the greater the α value, the higher the influence degree; the structural parameter with α≤0 is a non-significant factor, the smaller the α value, the lower the influence degree.

[0024] Preferably, the inner cooling tool is designed according to the significant factor and the influence degree of the significant factor, specifically including:

[0025] The inner cooling hole of the inner cooling tool is sorted according to the significant factor and the influence degree, the significant factor with the highest influence degree is designed preferentially, the strength of the inner cooling tool is improved under the premise of ensuring the rationality of the significant factor design, and finally the non-significant factor of the inner cooling hole is designed.

[0026] In another aspect, a design system of an inner-cooled tool comprises:

[0027] a structure parameter decomposition module configured to decompose structure parameters of the inner-cooled hole, the structure parameters comprising at least a diameter of the inner-cooled hole, a pitch of the inner-cooled hole, and an angle of the inner-cooled hole;

[0028] an orthogonal experiment module configured to design an orthogonal experiment scheme according to the decomposed structure parameters of the inner-cooled hole, and obtain a deformation of the inner-cooled tool;

[0029] a significant factor obtaining module configured to find out, from the structure parameters of the inner-cooled hole, a significant factor affecting a structural strength of the inner-cooled tool, an influence degree of the significant factor, and a non-significant factor, based on the deformation of the inner-cooled tool;

[0030] an inner-cooled tool design module configured to design the inner-cooled tool according to the significant factor, the influence degree of the significant factor, and the non-significant factor.

[0031] Preferably, the structure parameter decomposition module further comprises:

[0032] a structure analysis module configured to complete a structure analysis of the inner-cooled hole according to a specification of the inner-cooled tool.

[0033] Compared with the prior art, the present application has the following advantages:

[0034] (1) The present application uses an orthogonal analysis method to find out a significant factor affecting a structural strength of the inner-cooled tool from structure parameters of the inner-cooled hole, and optimizes a structural design of the inner-cooled tool according to the significant factor affecting the structural strength of the inner-cooled tool, so as to obtain a design scheme minimizing a reduction of the structural strength of the inner-cooled tool under the condition of meeting a flow requirement of cutting fluid;

[0035] (2) The present application uses a simulation method to perform an experiment, which is more efficient than a conventional physical experiment and is more suitable for multi-factor verification.

[0036] The above description is only a summary of the technical scheme of the present application. In order to more clearly understand the technical means of the present application, the content of the specification can be implemented, and in order to make the above and other purposes, characteristics and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are listed.

[0037] According to the detailed description of the specific embodiments of the present application below in combination with the drawings, those skilled in the art will more clearly understand the above and other purposes, advantages and characteristics of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a design method flow chart of the inner-cooled tool of the embodiments of the present application;

[0039] Figure 2It is the schematic view of the inner cooling four-blade flat-end end mill of the embodiment of the present application.

[0040] Figure 3 It is the schematic view of the side blade load of the milling cutter of the embodiment of the present application.

[0041] Figure 4 It is the schematic view of the inner cooling hole design of the embodiment of the present application.

[0042] Figure 5 It is the relationship diagram of the deformation amount and the structure parameters of the embodiment of the present application; wherein, (a) is the angle of the inclined hole; (b) is the distance between the inclined holes; (c) is the diameter of the inclined hole.

[0043] Figure 6 It is the schematic view of the bending resistance experiment of the embodiment of the present application.

[0044] Figure 7 It is the schematic view of the rod and the cutter for the experiment of the present application.

[0045] Figure 8 It is the schematic view of the rod displacement-load curve of the embodiment of the present application.

[0046] Figure 9 It is the schematic view of the cutter displacement-load curve of the embodiment of the present application.

[0047] Figure 10 It is the structure block diagram of the design system of the inner cooling cutter of the embodiment of the present application. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application; obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application, and all other embodiments obtained by those skilled in the art without creative labor based on the embodiments in the present application shall fall within the protection scope of the present application.

[0049] In the description of the present application, it should be noted that the terms “include”, “contain” or any other variants thereof are intended to cover the non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes the elements inherent to such process, method, article or equipment. Without more limitations, the element defined by the sentence “including a…” does not exclude the presence of another identical element in the process, method, article or equipment including the element.

[0050] Referring to Figure 1 the embodiment of the present application, the design method of the inner cooling cutter comprises:

[0051] S102, decompose the structural parameters of the internal cooling holes; the structural parameters include at least the internal cooling hole diameter, the internal cooling hole spacing and the internal cooling hole angle;

[0052] S104. Based on the structural parameters of the decomposed internal cooling holes, an orthogonal experimental scheme was designed to obtain the deformation of the internal cooling tool.

[0053] S106, Based on the deformation of the internal cooling tool, identify the significant factors, the degree of influence of the significant factors and the non-significant factors that affect the structural strength of the internal cooling tool from the structural parameters of the internal cooling hole;

[0054] S108, internal cooling tools are designed based on significant factors, the degree of influence of significant factors, and non-significant factors.

[0055] Furthermore, before decomposing the structural parameters of the internal cooling holes, it also includes...

[0056] S101, Complete the structural analysis of the internal cooling hole according to the specifications of the internal cooling tool;

[0057] The structural parameters of the internal cooling holes are decomposed, specifically including:

[0058] The structural parameters of the internal cooling holes are decomposed based on structural analysis.

[0059] Furthermore, based on the decomposed structural parameters of the internal cooling holes, an orthogonal experimental scheme was designed to obtain the deformation of the internal cooling tool, specifically including:

[0060] Based on the number of structural parameters of the decomposed internal cooling holes, a simulation experiment scheme is designed using the orthogonal analysis method. The structural parameters are designed with equal distribution. The radial cutting force on the internal cooling tool is simulated using three-dimensional finite element software. The internal cooling tool model is simulated to obtain the deformation of the internal cooling tool.

[0061] Furthermore, based on the deformation of the internal cooling tool, the significant factors affecting the structural strength of the internal cooling tool, the degree of influence of the significant factors, and the insignificant factors are identified from the structural parameters of the internal cooling hole. These include:

[0062] Based on the deformation of the internal cooling tool, we identify the significant factors affecting the structural strength of the internal cooling tool, the degree of influence of these significant factors, and the insignificant factors from the structural parameters of the internal cooling hole. These factors include:

[0063] Based on the deformation of the internal cooling tool, F and F' are obtained using the F test method. 表 Based on F and F 表 From the structural parameters of the internal cooling orifice, identify the significant factor i, the degree of influence of significant factor i, and the insignificant factor x; i∈1,2,3..., x∈1,2,3...; the formula for calculating the degree of influence of each structural parameter is as follows:

[0064] α=FF表

[0065] Wherein, F is calculated according to experimental data; F 表 Obtained by looking up table; the structural parameter of α>0 is a significant factor, the greater the α value, the higher the influence degree; the structural parameter of α≤0 is a non-significant factor, the smaller the α value, the lower the influence degree.

[0066] Further, the inner-cooling cutter is designed according to the significant factors and the influence degrees of the significant factors, and specifically includes:

[0067] The inner-cooling holes of the inner-cooling cutter are sorted according to the significant factors and the influence degrees of the significant factors, the significant factor with the highest influence degree is designed preferentially, the strength of the inner-cooling cutter is improved under the premise of ensuring the rationality of the design of the significant factors, and finally, the non-significant factors of the inner-cooling holes are designed.

[0068] The design method of the inner-cooling cutter will be described in detail below by taking the example of an inner-cooling bar and a milling cutter made of stainless steel 316. The yield strength of the stainless steel 316 is 205 MPa, the tensile strength is 520 MPa, the elongation is 40%, and the Vickers hardness is 200 Hv. The mechanical properties are used to establish a structural model.

[0069] Referring to Figure 2 , when side milling, the cutting fluid is sprayed at a certain position away from the cutter tip, the flow field medium is air and water two-phase flow, and part of the bottom edge participates in cutting. Taking a D12*40 inner-cooling four-blade flat head end mill 1 as an example, the inner-cooling structure includes a main inner-cooling hole 2 and a side edge inner-cooling hole 3.

[0070] Referring to Figure 3 , a radial cutting load of 200 MPa is simulated to be applied on the peripheral edge.

[0071] Referring to Figure 4 , the structural parameters of the inner-cooling holes are experimented by taking the side edge inner-cooling hole 3 as an example.

[0072] The main structural parameters of the side edge inner-cooling hole include a hole angle 4, a hole diameter 5, and a hole spacing 6. The three factors are independent variables. Therefore, a factor level table with three factors and three levels is established, as shown in Table 1.

[0073] Table 1 Structural parameter level table

[0074] Figure 5 Figure 6 Figure 7 Figure 8 1 45 0 0.5 2 60 3 0.75 3 75 6 1

[0075] Next, the positions of the side edge inner-cooling holes are fixed, and the inner-cooling holes are evenly distributed on the effective cutting edge. An orthogonal simulation experiment is performed according to L9(3 4 ), and the experimental results are shown in Table 2.

[0076] Table 2 Strain experimental results

[0077] Figure 9 Figure 10 Figure 1 Figure 2 Figure 3 1 45 0 0.5 131.014 2 45 3 0.75 131.094 3 45 6 1 131.521 4 60 0 0.75 131.051 5 60 3 1 131.134 6 60 6 0.5 131.105 7 75 0 1 131.056 8 75 3 0.5 131.021 9 75 6 0.75 131.243

[0078] The calculated skew hole angle 4 bias sum of squares is 0.023, F is 0.451; the skew hole spacing 5 bias sum of squares is 0.107, F is 2.098; the skew hole diameter 6 bias sum of squares is 0.055, F is 1.078; F 表 1.046. By comparison, the skew hole angle 4 is a non-significant factor, and the skew hole spacing 5 and the skew hole diameter 6 are significant factors.

[0079] Referring to Figure 4 It can be seen from the data analysis that the skew hole spacing has the greatest impact on the strength of the internal cooling milling cutter, and the strength of the internal cooling milling cutter decreases most significantly as the spacing increases. The skew hole diameter has the second greatest impact, and the skew hole angle has the weakest impact, and 60° is the minimum value.

[0080] It should be noted that the above is only described with respect to the side edge internal cooling hole. Correspondingly, similar experimental analysis can also be performed on the main internal cooling hole, and similar conclusions can be obtained. In summary, the internal cooling hole spacing has the greatest impact on the strength of the internal cooling milling cutter, and the strength of the internal cooling milling cutter decreases most significantly as the spacing increases. The internal cooling hole size has the second greatest impact, and the internal cooling hole angle has the weakest impact, and 60° is the minimum value. Therefore, when designing the internal cooling hole with a fixed bottom edge internal cooling hole position, the internal cooling hole angle close to 60° can be selected after fully considering the tool shape and cutting fluid pressure, so that the internal cooling hole distribution is more compact, and the internal cooling hole size is reduced.

[0081] According to the orthogonal analysis result, the internal cooling hole of the D12*40 four-fluted flat-end milling cutter is set by the fixed bottom edge internal cooling hole position, and the internal cooling hole structure optimization is shown in Table 3.

[0082] Table 3 Internal cooling hole structure optimization

[0083] Figure 5 Figure 6 Figure 7 Figure 8 45° 1.25 2.5 Figure 9 60° 0.75 5

[0084] Referring to Figure 10 and Figure 1 To verify the strength improvement of the optimized internal cooling cutter, a stainless steel 316 material internal cooling bar and a four-fluted flat-end milling cutter before and after optimization are respectively made, a universal testing machine is used to perform a bending test to simulate the stress of the cutter during side milling, and the strength of the bar and the cutter before and after optimization is compared. The overhang is 45mm, the outer generatrix of the pressure head roller is aligned with the end face of the cutter, so that the test state remains consistent.

[0085] The displacement-load curves of the bar before and after optimization are shown in Figure 2 From Figure 3It can be seen that the strength of the inner cooling bar after optimization is significantly improved. Under the action of the simulated side milling radial load of 2500N, the strain value of the inner cooling bar after optimization is 173μm, and that before optimization is 222μm, and the strength of the bar is improved by 22.07%.

[0086] The tool displacement-load curves before and after optimization are shown in Figure 4 It can be seen that under the action of the simulated side milling radial load of 2500N, the strain value of the inner cooling bar after optimization is 173μm, and that before optimization is 222μm, and the strength of the bar is improved by 22.07%. Figure 5

[0087] The tool displacement-load curves before and after optimization are shown in Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 The design system of the inner cooling tool comprises:

[0088] The structure parameter decomposition module 1002 is configured to decompose the structure parameters of the inner cooling hole, wherein the structure parameters at least include the diameter of the inner cooling hole, the spacing of the inner cooling hole and the angle of the inner cooling hole;

[0089] The orthogonal experiment module 1004 is configured to design an orthogonal experiment scheme according to the decomposed structure parameters of the inner cooling hole, and obtain the deformation of the inner cooling tool.

[0090] The significant factor acquisition module 1006 is configured to find out the significant factors, the influence degree of the significant factors and the non-significant factors affecting the structural strength of the inner cooling tool from the structure parameters of the inner cooling hole based on the deformation of the inner cooling tool.

[0091] The inner cooling tool design module 1008 is configured to design the inner cooling tool according to the significant factors, the influence degree of the significant factors and the non-significant factors.

[0092] Preferably, the structure parameter decomposition module 1002 further comprises:

[0093] The structure analysis module 1001 is configured to complete the structure analysis of the inner cooling hole according to the specifications of the inner cooling tool.

[0094] The specific implementation of the design system of the inner cooling tool is the same as the design method of the inner cooling tool, and the embodiment will not be repeated.

[0095] The above description is only the preferred specific implementation of the present application; however, the protection scope of the present application is not limited to this. Any skilled person in the art can make equivalent replacements or changes to the technical solution of the present application and the improved concept thereof within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.​

Claims

1. A method of designing an internally cooled cutting tool, characterized by, The method comprises the following steps: decomposing the structural parameters of the inner cooling hole; the structural parameters at least include the inner cooling hole diameter, the inner cooling hole spacing and the inner cooling hole angle; designing an orthogonal experiment scheme according to the decomposed structural parameters of the inner cooling hole to obtain the deformation of the inner cooling tool; finding out the significant factors, the influence degree of the significant factors and the non-significant factors affecting the structural strength of the inner cooling tool from the structural parameters of the inner cooling hole based on the deformation of the inner cooling tool by F test method; wherein the inner cooling hole diameter and the inner cooling hole spacing are the significant factors, and the influence degree of the inner cooling hole spacing is greater than that of the inner cooling hole diameter based on the deformation; the inner cooling hole angle is the non-significant factor, and the deformation is the smallest when the inner cooling hole angle is 60°; designing the inner cooling tool according to the significant factors, the influence degree of the significant factors and the non-significant factors; specifically, the inner cooling hole spacing is preferentially optimized, the inner cooling hole diameter is secondly optimized, and the inner cooling hole angle is fixed at 60° for designing the inner cooling tool.

2. The design method of an internally cooled cutting tool according to claim 1, wherein Before decomposing the structural parameters of the inner cooling hole, the method further comprises the following steps: completing the structural analysis of the inner cooling hole according to the specifications of the inner cooling tool; decomposing the structural parameters of the inner cooling hole, specifically comprising: decomposing the structural parameters of the inner cooling hole based on the structural analysis.

3. The method of designing an internally cooled cutting tool according to claim 1, wherein Designing an orthogonal experiment scheme according to the number of the decomposed structural parameters of the inner cooling hole to obtain the deformation of the inner cooling tool, specifically comprising: designing a simulation experiment scheme by using the orthogonal analysis method according to the number of the decomposed structural parameters of the inner cooling hole; the structural parameters are designed by using the equal division method; the radial cutting force borne by the inner cooling tool is simulated by using the three-dimensional finite element software; the inner cooling tool model is simulated to obtain the deformation of the inner cooling tool.

4. The method of designing an internally cooled cutting tool according to Claim 1, wherein Finding out the significant factors, the influence degree of the significant factors and the non-significant factors affecting the structural strength of the inner cooling tool from the structural parameters of the inner cooling hole based on the deformation of the inner cooling tool, specifically comprising: According to the deformation of the inner-cooling tool, F and F are obtained by F test method 表 , and F and F are obtained based on F and F 表 Significant factors i and the influence degree of the significant factors i and non-significant factors x are found from the structural parameters of the inner-cooling hole; i∈1,2,3..., x∈1,2,3...; the calculation formula of the influence degree of each structural parameter is as follows: a = F - F 表 Wherein, F is calculated according to experimental data; F 表 Obtained by looking up table; structural parameters with α>0 are significant factors, and the greater the value of α, the higher the influence degree; structural parameters with α≤0 are non-significant factors, and the smaller the value of α, the lower the influence degree.

5. The method of designing an internally cooled cutting tool according to Claim 1, wherein designing the inner cooling tool according to the significant factors and the influence degree of the significant factors, specifically comprising: sequencing the inner cooling hole design of the inner cooling tool according to the significant factors and the influence degree; the significant factor with the highest influence degree is preferentially designed; the strength of the inner cooling tool is improved under the premise of ensuring the rationality of the significant factor design; finally, the non-significant factor design of the inner cooling hole is performed.

6. A design system of an inner-cooled cutting tool, characterized by comprising: The method comprises the following steps: a structural parameter decomposition module is configured to decompose the structural parameters of the inner cooling hole; the structural parameters at least include the inner cooling hole diameter, the inner cooling hole spacing and the inner cooling hole angle; an orthogonal experiment module is configured to design an orthogonal experiment scheme according to the decomposed structural parameters of the inner cooling hole to obtain the deformation of the inner cooling tool; a significant factor acquisition module is configured to find out the significant factors, the influence degree of the significant factors and the non-significant factors affecting the structural strength of the inner cooling tool from the structural parameters of the inner cooling hole based on the deformation of the inner cooling tool by F test method; wherein the inner cooling hole diameter and the inner cooling hole spacing are the significant factors, and the influence degree of the inner cooling hole spacing is greater than that of the inner cooling hole diameter based on the deformation; the inner cooling hole angle is the non-significant factor, and the deformation is the smallest when the inner cooling hole angle is 60°; an inner cooling tool design module is configured to design the inner cooling tool according to the significant factors, the influence degree of the significant factors and the non-significant factors; specifically, the inner cooling hole spacing is preferentially optimized, the inner cooling hole diameter is secondly optimized, and the inner cooling hole angle is fixed at 60° for designing the inner cooling tool.

7. The design system of an internally cooled cutting tool according to claim 6, wherein Before the structural parameter decomposition module, the method further comprises the following steps: A structure analysis module is configured to complete the structure analysis of the inner cooling hole according to the inner cooling tool specification.

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