Method and device for evaluating cutting performance of drill point

Abstract

The invention relates to the technical field of drill point design, and particularly discloses a drill point cutting performance evaluation method and device.The drill point cutting performance evaluation method comprises the steps that a drill point three-dimensional model is controlled to conduct drilling simulation on a machined part three-dimensional model according to the main shaft rotating speed and the feeding speed in machining parameters, and drilling parameters in the drilling simulation process are obtained; evaluating the drill point according to the obtained drilling parameters so as to obtain an optimal drill point suitable for the processed workpiece; compared with a method for directly drilling a solid plate by adopting multiple drill needles to determine which drill needle has a relatively ideal drilling effect, the method for evaluating the cutting performance of the drill needle provided by the embodiment of the invention has the advantages that the efficiency of selecting the optimal drill needle suitable for the processed workpiece is higher, the test period is greatly shortened, a real probe does not need to be adopted, the cost is lower, and the method is suitable for popularization and application. And the test result is not influenced by the environment.

Description

Technical Field

[0001] This invention relates to the field of drill bit design technology, and in particular to a method and apparatus for evaluating the cutting performance of drill bits. Background Technology

[0002] In the field of electronics manufacturing, printed circuit boards are a key basic component of electronic devices, and their molding quality directly affects the performance and reliability of electronic devices.

[0003] Due to increasingly higher wiring density in current product designs, signal vias are increasingly designed with micro-vias of 0.2mm or less. Furthermore, high-end printed circuit boards (PCBs), such as AI development boards, communication boards, and aerospace boards, are moving towards multi-layered designs, low coefficients of thermal expansion, and thicker copper inner power layers. These high-end PCBs require higher aspect ratios. Based on these factors, a single broken drill bit in a hole on a high-end PCB can often render the entire PCB unusable, significantly increasing its cost.

[0004] To reduce the breakage rate, a single drill bit typically needs to be tested tens of thousands, or even hundreds of thousands of times, resulting in high testing costs and long testing cycles. Furthermore, due to the long testing cycle, fluctuations in the testing environment can also affect the test results. Summary of the Invention

[0005] The purpose of this invention is to provide a method and apparatus for evaluating drill bit cutting performance, which can reduce testing costs, shorten the testing cycle, and avoid the influence of the testing environment on the test results.

[0006] On one hand, the present invention provides a method for evaluating the cutting performance of a drill bit, the method comprising the following steps:

[0007] Obtain the machining parameters of the drill bit, including the spindle speed, feed rate, drilling depth, and hole diameter;

[0008] The design parameters of at least one drill bit are determined based on the machining parameters of the drill bit, and a three-dimensional model of the drill bit is generated based on the design parameters of the drill bit. The design parameters of the drill bit include the drill tip angle, the first flank face angle, the second flank face angle, the outer diameter of the drill bit, the core thickness of the drill bit, the core thickness taper, the helix angle, the cutting edge length, and the groove length.

[0009] A three-dimensional model of the workpiece is generated based on the machining parameters and design parameters of the drill bit.

[0010] The three-dimensional model of the drill bit is assembled onto the three-dimensional model of the workpiece, and the three-dimensional model of the drill bit is controlled to perform drilling simulation on the three-dimensional model of the workpiece according to the spindle speed and feed rate in the machining parameters.

[0011] Obtain drilling parameters during the drilling simulation process, including cutting force, cutting torque, and maximum stress;

[0012] The drill bit is evaluated based on the obtained drilling parameters.

[0013] The drill bit cutting performance evaluation method provided by this invention has at least the following beneficial effects:

[0014] This drill bit cutting performance evaluation method controls the three-dimensional model of the drill bit to perform drilling simulation on the three-dimensional model of the workpiece based on the spindle speed and feed rate in the machining parameters, and obtains the drilling parameters during the drilling simulation process. Then, the drill bit is evaluated based on the obtained drilling parameters to obtain the optimal drill bit suitable for the workpiece. Compared with directly using multiple drill bits to drill holes in solid plates to determine which drill bit has the most ideal drilling effect, the drill bit cutting performance evaluation method provided in this embodiment is more efficient in selecting the optimal drill bit suitable for the workpiece, the test cycle is greatly shortened, no physical probe is required, the cost is lower, and the test results are not affected by the environment.

[0015] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the step of generating a three-dimensional model of the workpiece based on the machining parameters and design parameters of the drill bit includes the following steps:

[0016] The design parameters of the workpiece are determined based on the machining parameters and design parameters of the drill bit. The design parameters of the workpiece include the diameter of the center hole, the diameter of the transverse cutting edge limiting plate, the diameter of the main cutting edge limiting plate, the inner diameter of the boundary platform, and the outer diameter of the boundary platform.

[0017] Generate a three-dimensional model of the workpiece based on its design parameters.

[0018] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the diameter of the central hole is 2R1, and the outer diameter of the drill bit is D, where 0.01D≤R1≤0.05D;

[0019] And / or, the outer diameter of the transverse blade limiting disc is 2R2. Where w represents the core thickness of the drill bit, α represents the drill tip angle of the drill bit, β1 represents the first flank face angle, and β2 represents the second flank face angle;

[0020] And / or, the inner diameter of the boundary platform is D1, and the outer diameter of the boundary platform is D2, where 1.2D1 < D2 < 2D1;

[0021] And / or, the outer diameter of the main cutting edge limiting disk is 2R3, and the inner diameter of the boundary platform is D1, where D1 = 2R4 and R3 = R4.

[0022] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the transverse cutting edge limiting disc has a first limiting edge for limiting the transverse cutting edge of the drill bit, and a second limiting edge for limiting the centerline of the drill bit. The included angle between the projections of the first limiting edge and the second limiting edge in a plane perpendicular to the axial direction of the center hole is θ0. ;

[0023] The transverse blade limiting disc has two symmetrically distributed limiting inclined surfaces, and the angle between the second limiting edge and the limiting inclined surface is γ. ;

[0024] The design parameters of the workpiece also include the included angle γ between the second limiting edge and the limiting inclined surface.

[0025] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the main cutting edge limiting disk has two main cutting edge limiting edges for limiting the two main cutting edges of the drill bit respectively, and the distance between the two main cutting edge limiting edges is L, L = w;

[0026] The design parameters of the workpiece also include the distance L between the two limiting edges of the main cutting edges.

[0027] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the workpiece has a first surface that can contact the first flank face of the drill bit, and the included angle between the first surface and the first flank face of the drill bit is A1, 0°≤A1≤15°;

[0028] The workpiece has a second surface that can contact the second flank face of the drill bit, and the included angle between the second surface and the second flank face of the drill bit is A2, 0°≤A2≤45°;

[0029] The workpiece has a first upper surface located in the transverse cutting area of ​​the drill bit and a second upper surface located in the main cutting edge cutting area of ​​the drill bit. Both the first upper surface and the second upper surface are helical surfaces. The pitch of the first upper surface and the pitch of the second upper surface are both H / 2. The feed per revolution of the drill bit is f, where f < H < πDtanφ, and φ represents the helix angle of the drill bit.

[0030] The design parameters of the workpiece also include the angle A1 between the first surface and the first flank face of the drill bit, the angle A2 between the second surface and the second flank face of the drill bit, the pitch of the first upper surface, and the pitch of the second upper surface.

[0031] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the step of evaluating the drill bit based on the acquired drilling parameters includes the following steps:

[0032] The score P of the drill bit is determined based on the obtained drilling parameters, where P = XYZ. , , F represents the maximum cutting force during the drilling simulation process, and Z represents the maximum cutting force. f The length of the drill bit is represented by σ, where D represents the outer diameter of the drill bit. S H represents the fracture stress of a material. d The value represents the drilling depth, T represents the maximum cutting torque during the drilling simulation, w represents the core thickness of the drill bit, and σ represents the depth of cut. max This represents the maximum stress during the drilling simulation process;

[0033] The optimal drill bit is determined based on the score.

[0034] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, when determining the design parameters of a drill bit based on the machining parameters of the drill bit, the optimal drill bit is determined based on the score, including the following steps:

[0035] When P ≤ P1, the drill bit is defective. The design parameters of the drill bit are optimized until P > P1. When P > P1, the drill bit is qualified.

[0036] Alternatively, when determining the design parameters of at least two drill bits based on the machining parameters of the drill bit, the optimal drill bit is determined based on a score, including the following steps:

[0037] Among all the drill bits with P > P1, the drill bit represented by the largest P is the optimal drill bit;

[0038] P1 is a predetermined known value and P1 > 0.

[0039] As one possible implementation of the above-mentioned drill bit cutting performance evaluation method, the step of obtaining drilling parameters during the drilling simulation process includes:

[0040] Obtain drilling parameters during the drilling simulation process, from the start of the drill bit's rotation to the preset rotation angle of the drill bit;

[0041] Alternatively, the drilling parameter in the drilling simulation process may be the duration of the drill bit rotation reaching a preset duration.

[0042] On the other hand, the present invention provides a drill bit cutting performance evaluation device, comprising:

[0043] The machining parameter module is used to obtain the machining parameters of the drill bit, including the spindle speed, feed rate, drilling depth and hole diameter of the drill bit;

[0044] The drill bit parameter determination module is used to determine the design parameters of at least one drill bit based on the processing parameters, and to generate a three-dimensional model of the drill bit based on the design parameters. The design parameters of the drill bit include the drill tip angle, the first flank face angle, the second flank face angle, the outer diameter of the drill bit, the core thickness of the drill bit, the core thickness taper, the helix angle, the cutting edge length, and the groove length.

[0045] The workpiece simulation module is used to generate a three-dimensional model of the workpiece based on the machining parameters and design parameters of the drill bit.

[0046] The drilling simulation module is used to assemble the three-dimensional model of the drill bit onto the three-dimensional model of the workpiece, and control the three-dimensional model of the drill bit to perform drilling simulation on the three-dimensional model of the workpiece according to the spindle speed and feed rate in the machining parameters.

[0047] The drilling parameter acquisition module is used to acquire the drilling parameters of the drill bit during the drilling simulation process. The drilling parameters include cutting force, cutting torque and maximum stress.

[0048] The performance evaluation module is used to evaluate the drill bit based on the acquired drilling parameters.

[0049] The drill bit cutting performance evaluation device provided by the present invention has at least the following beneficial effects:

[0050] This drill bit cutting performance evaluation device can reduce testing costs, shorten the testing cycle, and avoid the test environment affecting the test results. Attached Figure Description

[0051] Figure 1 This is a flowchart of the drill bit cutting performance evaluation method in an embodiment of the present invention;

[0052] Figure 2 This is a schematic diagram showing the parameter annotations of the drill bit from a first perspective in an embodiment of the present invention;

[0053] Figure 3 This is a schematic diagram of the drill bit structure from a second perspective in an embodiment of the present invention;

[0054] Figure 4 This is a first partially enlarged schematic diagram of the drill bit in an embodiment of the present invention;

[0055] Figure 5 This is a second partially enlarged schematic diagram of the drill bit in an embodiment of the present invention;

[0056] Figure 6 This is a schematic diagram showing the parameter annotations of the drill bit from a second perspective in an embodiment of the present invention;

[0057] Figure 7This is a schematic diagram of the structure of the workpiece in an embodiment of the present invention;

[0058] Figure 8 This is a top view of the workpiece in an embodiment of the present invention;

[0059] Figure 9 This is a cross-sectional view of the workpiece in an embodiment of the present invention;

[0060] Figure 10 This is a partial cross-sectional view of the workpiece in an embodiment of the present invention.

[0061] In the picture:

[0062] 1. Drill bit; 11. Main cutting edge; 12. Chisel edge; 13. First flank face; 14. Second flank face; 15. Centerline;

[0063] 2. Workpiece; 21. Main cutting edge limiting plate; 22. Chisel edge limiting plate; 23. Boundary platform; 24. Center hole;

[0064] P1, First surface; P2, Second surface; P3, First upper surface; P4, Second upper surface;

[0065] L1, first limiting edge; L2, second limiting edge; L3, main cutting edge limiting edge. Detailed Implementation

[0066] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0067] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0068] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0069] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0070] The embodiments of the present invention provide a method for evaluating the cutting performance of a drill bit, so as to reduce testing costs, shorten the testing cycle, and avoid the influence of the testing environment on the test results.

[0071] like Figures 1 to 10 As shown, the method for evaluating the cutting performance of a drill bit includes the following steps:

[0072] S100. Obtain the machining parameters of drill bit 1. The machining parameters of drill bit 1 include the spindle speed, feed rate, drilling depth and hole diameter of drill bit 1.

[0073] S200. Determine at least one design parameter for drill bit 1 based on the machining parameters of drill bit 1, and generate a three-dimensional model of drill bit 1 based on the design parameters of drill bit 1. The design parameters of drill bit 1 include drill tip angle, first flank face angle, second flank face angle, outer diameter of drill bit 1, core thickness of drill bit 1, core thickness taper, helix angle, cutting edge length and groove length.

[0074] S300. Generate a three-dimensional model of the workpiece 2 based on the machining parameters and design parameters of drill bit 1.

[0075] S400. Assemble the three-dimensional model of drill bit 1 onto the three-dimensional model of workpiece 2. Control the three-dimensional model of drill bit 1 to perform drilling simulation on the three-dimensional model of workpiece 2 according to the spindle speed and feed rate in the machining parameters.

[0076] S500: Obtain drilling parameters during the drilling simulation process, including cutting force, cutting torque, and maximum stress.

[0077] S600. Evaluate the drill bit 1 based on the obtained drilling parameters.

[0078] This drill bit cutting performance evaluation method controls the three-dimensional model of drill bit 1 to perform drilling simulation on the three-dimensional model of workpiece 2 based on the spindle speed and feed rate in the machining parameters, and obtains the drilling parameters during the drilling simulation process. Then, the drill bit 1 is evaluated based on the obtained drilling parameters to obtain the optimal drill bit 1 suitable for workpiece 2. Compared with directly using multiple drill bits to drill holes in solid plates to determine which drill bit has the most ideal drilling effect, the drill bit cutting performance evaluation method provided in this embodiment is more efficient in selecting the optimal drill bit 1 suitable for workpiece 2, the test cycle is greatly shortened, no physical probe is required, the cost is lower, and the test results are not affected by the environment.

[0079] In step S200, the groove length refers to the length of the chip removal groove on the drill bit 1 along the axial direction of the drill bit 1.

[0080] When drill bit 1 first penetrates a flat plate, its chisel edge 12 contacts the plate and generates force. Simultaneously, because the chisel edge 12 has a negative rake angle, it causes significant deformation of the plate, resulting in large mesh deformation during drilling simulation. This not only prolongs the drilling simulation time but also leads to instability in the simulation. Therefore, in some embodiments, a three-dimensional model of the workpiece 2 is generated based on the machining parameters and design parameters of drill bit 1. Step S300 includes the following steps:

[0081] S310. Determine the design parameters of the workpiece 2 based on the machining parameters and design parameters of the drill bit 1. The design parameters of the workpiece 2 include the diameter of the center hole 24, the diameter of the transverse cutting edge limiting plate 22, the diameter of the main cutting edge limiting plate 21, the inner diameter of the boundary platform 23, and the outer diameter of the boundary platform 23.

[0082] S320. Generate a three-dimensional model of workpiece 2 based on the design parameters of workpiece 2.

[0083] Since the three-dimensional model of the workpiece 2 is based on the drill bit structure design, by limiting the diameter of the center hole 24, the diameter of the chisel edge limiting plate 22, the diameter of the main cutting edge limiting plate 21, and the diameter of the boundary platform 23, the drill bit and the workpiece can achieve a good fit from the beginning. This effectively avoids the initial stage of unstable cutting of the chisel edge 12 when directly drilling into the plate, which can improve the stability of the cutting force in the cutting simulation process, so as to obtain accurate drilling parameters and improve the accuracy of the evaluation results; moreover, the simulation efficiency is higher, which is conducive to shortening the test cycle.

[0084] Specifically, such as Figures 2 to 10 As shown, the design parameters of workpiece 2 are determined as follows:

[0085] The diameter of the center hole 24 is 2R1, and the outer diameter of the drill bit 1 is D, where 0.01D≤R1≤0.05D.

[0086] The outer diameter of the transverse blade limiting disc 22 is 2R2. ;

[0087] Where w represents the core thickness of drill bit 1, α represents the drill tip angle of drill bit, β1 represents the first back face angle, and β2 represents the second back face angle.

[0088] The inner diameter of the boundary platform 23 is D1, and the outer diameter of the boundary platform 23 is D2, where 1.2D1 < D2 < 2D1; the outer diameter of the main cutting edge limiting disk 21 is 2R3, where D1 = 2R4 and R3 = R4.

[0089] In some embodiments, the transverse cutting edge limiting disc 22 has a first limiting edge L1 for limiting the transverse cutting edge 12 of the drill bit 1, and a second limiting edge L2 for limiting the center line 15 of the drill bit 1. The angle between the projections of the first limiting edge L1 and the second limiting edge L2 in a plane perpendicular to the axial direction of the central hole 24 is θ0. .

[0090] The transverse cutting edge limiting plate 22 has two symmetrically distributed limiting inclined surfaces, and the angle between the second limiting edge L2 and the limiting inclined surface is γ. .

[0091] The main cutting edge limiting disk 21 has two main cutting edge limiting edges L3 for limiting the two main cutting edges 11 of the drill bit 1 respectively. The distance between the two main cutting edge limiting edges L3 is L, where L = w, and w represents the core thickness of the drill bit 1. The design parameters of the workpiece 2 also include the distance L between the two main cutting edge limiting edges L3.

[0092] In some embodiments, the workpiece 2 has a first surface P1 that can contact the first flank face 12 of the drill bit 1, and the angle between the first surface P1 and the first flank face 12 of the drill bit is A1, 0°≤A1≤15°; the workpiece 2 has a second surface P2 that can contact the second flank face 14 of the drill bit 1, and the angle between the second surface P2 and the second flank face 14 of the drill bit 1 is A2, 0°≤A2≤45°; the workpiece 2 has a first upper surface P3 located in the chisel edge cutting area of ​​the drill bit 1, and a second upper surface P4 located in the main cutting edge cutting area of ​​the drill bit 1, both the first upper surface P3 and the second upper surface P4 are helical surfaces, the pitch of the first upper surface P3 and the pitch of the second upper surface P4 are both H1, H1=H / 2, the feed per revolution of the drill bit 1 is f, f<H<πDtanφ, φ represents the helix angle of the drill bit 1.

[0093] The design parameters of the workpiece 2 also include the angle A1 between the first surface P1 and the first flank face 13 of the drill bit 1, the angle A2 between the second surface P2 and the second flank face 14 of the drill bit 1, the pitch of the first upper surface P3 and the pitch of the second upper surface P4.

[0094] In some embodiments, obtaining drilling parameters during the drilling simulation process includes:

[0095] Obtain drilling parameters during the drilling simulation process, from the start of the rotation of drill bit 1 to the preset rotation angle of drill bit 1; or, obtain drilling parameters during the drilling simulation process, such as the duration of the rotation of drill bit 1 reaching a preset duration.

[0096] Obtaining drilling parameters from a drilling simulation process can improve the accuracy of these parameters, thereby enhancing the accuracy of the evaluation results.

[0097] It should be noted that the above-mentioned preset angle is a known value determined by those skilled in the art based on the spindle speed, feed rate, and drilling depth, and the above-mentioned preset duration is a known value determined by those skilled in the art based on the spindle speed, feed rate, and drilling depth.

[0098] In some embodiments, evaluating the drill bit 1 based on the acquired drilling parameters, i.e., step S600 includes the following steps:

[0099] S610. Determine the score P of drill bit 1 based on the obtained drilling parameters, P = XYZ. , , F represents the maximum cutting force during the drilling simulation process, and Z represents the maximum cutting force. f σ represents the cutting edge length of drill bit 1, D represents the outer diameter of drill bit 1, and σ represents the cutting edge length of drill bit 1. S H represents the fracture stress of a material. d The value represents the drilling depth, T represents the maximum cutting torque during the drilling simulation, w represents the core thickness of drill bit 1, and σ represents the depth of cut. max This represents the maximum stress during the drilling simulation process.

[0100] S620. Determine the optimal drill bit 1 based on the score.

[0101] To facilitate data processing, the three drilling parameters are processed to obtain coefficients X, Y, and Z, which are then used to determine the score P.

[0102] It should be noted that drilling parameters are not limited to the maximum cutting force F and the maximum stress σ during the drilling simulation process. max The maximum cutting torque T during the drilling simulation process can also take into account other parameters of the drill bit 1 during the drilling process, so that the determined drill bit 1 is more suitable for the workpiece 2.

[0103] In step S200, when determining the design parameters of a drill bit 1 based on its machining parameters, step S600 includes the following steps:

[0104] When P ≤ P1, drill bit 1 is unqualified. The design parameters of drill bit 1 are optimized until P > P1. When P > P1, drill bit 1 is qualified. Here, P1 is a known value predetermined based on the machining parameters and design parameters of drill bit 1, and P1 > 0.

[0105] If P < 0, it indicates that drill bit 1 has a high risk of failure and requires design optimization, such as increasing the core thickness of drill bit 1. If 0 < P ≤ P1, the machining parameters of drill bit 1 also need optimization. If P > P1, it indicates that drill bit 1 is qualified and can be directly machined according to its design parameters. The spindle speed and feed rate in the machining parameters of drill bit 1 are used to machine the flat plate, ensuring that the drilling depth and diameter of the drilled hole conform to the machining parameters of drill bit 1.

[0106] In step S200, when determining the design parameters of at least two drill bits 1 based on the machining parameters of drill bit 1, step S600 includes the following steps:

[0107] Among all drill bits 1 with P > P1, the drill bit 1 represented by the largest P is the optimal drill bit 1.

[0108] Specifically, if there exists a drill bit 1 with P > P1, then the drill bit 1 represented by the largest P among all drill bits 1 with P > P1 is selected as the optimal drill bit 1. If there is no drill bit 1 with P > P1, then the design parameters of each drill bit 1 are optimized.

[0109] In some embodiments, in step S500, the cutting force, cutting torque and stress in the drilling simulation process are obtained by performing finite element analysis on the drilling simulation process.

[0110] In step S600, the maximum cutting force F is found from all cutting forces obtained during the drilling simulation; the maximum cutting torque T is found from all cutting torques obtained during the drilling simulation; and the maximum stress σ is found from all stresses obtained during the drilling simulation. max .

[0111] In step S200, a three-dimensional model of drill bit 1 is generated using finite element software. In step S300, a three-dimensional model of workpiece 2 is generated using finite element software. The determination of the design parameters of drill bit 1 based on its machining parameters in step S200 is existing technology in this field and will not be described in detail here.

[0112] Taking the determination of the design parameters of a drill bit 1 based on its machining parameters as an example, the machining parameters of the drill bit 1 are as follows: the thickness of the circuit board is 3mm, that is, the drilling depth H d =3mm, the diameter of the hole to be drilled is 0.2mm, that is, the diameter of the hole is 0.2mm; the spindle speed is 125krev / min, the feed rate is 2.5m / min, and the feed per revolution is f = 20μ / rev = 0.02mm / rev.

[0113] Based on the machining parameters of drill bit 1, the design parameters of drill bit 1 are determined as follows: drill tip angle α = 130°, first flank face angle β1 = 12°, second flank face angle β2 = 30°, outer diameter D = 0.2 mm, core thickness w = 0.08 mm, helix angle φ = 40°, and cutting length Z. f = 4.5mm, groove length Z g =4.3mm, core thickness taper is 2%.

[0114] The three-dimensional model of drill bit 1 is determined based on the design parameters of drill bit 1.

[0115] The design parameters of the workpiece 2 are determined based on the design parameters and machining parameters of drill bit 1, and then a three-dimensional model of the workpiece 2 is generated based on the design parameters of workpiece 1. Specifically, the material of workpiece 2 is tungsten steel, σ S=4000MPa, the design parameters of the workpiece 2 are as follows: 2R1=0.03D=0.006mm, R2=0.055mm, R3=R4=D, θ0=46.9°, γ=163.3°, L=w=0.08mm, pitch H1=0.010mm.

[0116] The drilling parameters for a simulated cutting process with a preset angle of 15° were obtained. Specifically, the maximum cutting force F = 0.6 N, the maximum cutting torque T = 0.015 N·mm, and σ max =2800MPa, and the calculated value of P is 0.2543. P meets the requirements.

[0117] This embodiment also provides a drill bit cutting performance evaluation device for implementing the above-mentioned drill bit cutting performance evaluation method. The drill bit cutting performance evaluation device can be implemented in software and / or hardware.

[0118] Specifically, the drill bit cutting performance evaluation device includes a machining parameter module, a drill bit parameter determination module, a workpiece simulation module, a drilling simulation module, a drilling parameter acquisition module, and a performance evaluation module.

[0119] The machining parameter module is used to obtain the machining parameters of the drill bit 1, including the spindle speed, feed rate, drilling depth and hole diameter of the drill bit 1.

[0120] The drill bit parameter determination module is used to determine the design parameters of at least one drill bit 1 based on the machining parameters, and to generate a three-dimensional model of the drill bit 1 based on the design parameters. The design parameters of the drill bit 1 include the drill tip angle, the first flank face angle, the second flank face angle, the outer diameter of the drill bit 1, the core thickness of the drill bit, the core thickness taper, the helix angle, the cutting edge length, and the groove length.

[0121] The workpiece simulation module is used to generate a three-dimensional model of the workpiece 2 based on the machining parameters and design parameters of drill bit 1.

[0122] The drilling simulation module is used to assemble the three-dimensional model of drill bit 1 onto the three-dimensional model of workpiece 2, and control the three-dimensional model of drill bit 1 to perform drilling simulation on the three-dimensional model of workpiece 2 according to the spindle speed and feed rate in the machining parameters.

[0123] The drilling parameter acquisition module is used to acquire the drilling parameters of drill bit 1 during the drilling simulation process. The drilling parameters include cutting force, cutting torque and maximum stress.

[0124] The performance evaluation module is used to evaluate drill bit 1 based on the acquired drilling parameters.

[0125] The drill bit cutting performance evaluation device provided in this embodiment of the invention can execute the drill bit cutting performance evaluation method provided in any embodiment of the invention, and has the same beneficial effects as the drill bit cutting performance evaluation method, which will not be described in detail here.

[0126] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for evaluating the cutting performance of a drill bit, characterized in that, Includes the following steps: Obtain the machining parameters of the drill bit (1), which include the spindle speed, feed rate, drilling depth and hole diameter of the drill bit (1); The design parameters of at least one drill bit (1) are determined based on the machining parameters of the drill bit (1), and a three-dimensional model of the drill bit (1) is generated based on the design parameters of the drill bit (1). The design parameters of the drill bit (1) include the drill tip angle, the first back face angle, the second back face angle, the outer diameter of the drill bit (1), the core thickness of the drill bit (1), the core thickness taper, the helix angle, the cutting edge length, and the groove length. A three-dimensional model of the workpiece (2) is generated based on the machining parameters of the drill bit (1) and the design parameters of the drill bit (1); The three-dimensional model of the drill bit (1) is assembled into the three-dimensional model of the workpiece (2). The three-dimensional model of the drill bit (1) is controlled to perform drilling simulation on the three-dimensional model of the workpiece (2) according to the spindle speed and feed rate in the machining parameters. Obtain drilling parameters during the drilling simulation process, including cutting force, cutting torque, and maximum stress; The drill bit (1) is evaluated based on the obtained drilling parameters.

2. The method for evaluating the cutting performance of a drill bit according to claim 1, characterized in that, The process of generating a three-dimensional model of the workpiece (2) based on the machining parameters and design parameters of the drill bit (1) includes the following steps: The design parameters of the workpiece (2) are determined according to the machining parameters of the drill bit (1) and the design parameters of the drill bit (1). The design parameters of the workpiece (2) include the diameter of the center hole (24), the diameter of the transverse cutting edge limiting plate (22), the diameter of the main cutting edge limiting plate (21), the inner diameter of the boundary platform (23), and the outer diameter of the boundary platform (23). A three-dimensional model of the workpiece (2) is generated based on the design parameters of the workpiece (2).

3. The method for evaluating the cutting performance of a drill bit according to claim 2, characterized in that, The diameter of the central hole (24) is 2R1, and the outer diameter of the drill bit (1) is D, where 0.01D≤R1≤0.05D; And / or, the outer diameter of the transverse blade limiting disc (22) is 2R2, Where w represents the core thickness of the drill bit (1), α represents the drill tip angle of the drill bit (1), β1 represents the first back face angle, and β2 represents the second back face angle; And / or, the inner diameter of the boundary platform (23) is D1, and the outer diameter of the outer circle of the boundary platform (23) is D2, 1.2D1<D2<2D1; And / or, the outer diameter of the main cutting edge limiting disk (21) is 2R3, and the inner diameter of the boundary platform (23) is D1, D1 = 2R4, R3 = R4.

4. The method for evaluating the cutting performance of a drill bit according to claim 3, characterized in that, The transverse cutting edge limiting disc (22) has a first limiting edge (L1) for limiting the transverse cutting edge (12) of the drill bit (1) and a second limiting edge (L2) for limiting the center line (15) of the drill bit (1). The angle between the projections of the first limiting edge (L1) and the second limiting edge (L2) in a plane perpendicular to the axial direction of the central hole (24) is θ0. ; The transverse blade limiting disc (22) has two symmetrically distributed limiting inclined surfaces, and the angle between the second limiting edge (L2) and the limiting inclined surface is γ. ; The design parameters of the workpiece (2) also include the included angle γ between the second limiting edge (L2) and the limiting inclined surface.

5. The method for evaluating the cutting performance of a drill bit according to claim 3, characterized in that, The main cutting edge limiting disk (21) has two main cutting edge limiting edges (L3) for limiting the two main cutting edges (11) of the drill bit (1) respectively, and the distance between the two main cutting edge limiting edges (L3) is L, L = w; The design parameters of the workpiece (2) also include the distance L between the two main cutting edge limiting edges (L3).

6. The method for evaluating the cutting performance of a drill bit according to claim 2, characterized in that, The workpiece (2) has a first surface (P1) that can contact the first flank face (13) of the drill bit (1), and the included angle between the first surface (P1) and the first flank face (13) of the drill bit (1) is A1, 0°≤A1≤15°; The workpiece (2) has a second surface (P2) that can contact the second flank face (14) of the drill bit (1), and the included angle between the second surface (P2) and the second flank face (14) of the drill bit (1) is A2, 0°≤A2≤45°; The workpiece (2) has a first upper surface (P3) located in the transverse cutting area of ​​the drill bit (1) and a second upper surface (P4) located in the main cutting edge cutting area of ​​the drill bit (1). The first upper surface (P3) and the second upper surface (P4) are both helical surfaces. The pitch of the first upper surface (P3) and the pitch of the second upper surface (P4) are both H / 2. The feed per revolution of the drill bit (1) is f, f < H < πDtanφ, where φ represents the helix angle of the drill bit (1). The design parameters of the workpiece (2) also include the angle A1 between the first surface (P1) and the first back face (13) of the drill bit (1), the angle A2 between the second surface (P2) and the second back face (14) of the drill bit (1), the pitch of the first upper surface (P3) and the pitch of the second upper surface (P4).

7. The method for evaluating the cutting performance of a drill bit according to any one of claims 1 to 5, characterized in that, The evaluation of the drill bit (1) based on the acquired drilling parameters includes the following steps: The score P of the drill bit (1) is determined based on the obtained drilling parameters, where P = XYZ. , , F represents the maximum cutting force during the drilling simulation process, and Z represents the maximum cutting force. f The length of the cutting edge of the drill bit (1) is represented by D, and the outer diameter of the drill bit (1) is represented by σ. S H represents the fracture stress of a material. d The value represents the drilling depth, T represents the maximum cutting torque during the drilling simulation, w represents the core thickness of the drill bit (1), and σ represents the core thickness of the drill bit (1). max This represents the maximum stress during the drilling simulation process; The optimal drill bit is determined based on the score (1).

8. The method for evaluating the cutting performance of a drill bit according to claim 7, characterized in that, When determining the design parameters of a drill bit (1) based on the machining parameters of the drill bit (1), the optimal drill bit (1) is determined based on the scoring, including the following steps: When P≤P1, the drill bit (1) is unqualified. The design parameters of the drill bit (1) are optimized until P>P1. When P>P1, the drill bit (1) is qualified. Alternatively, when determining the design parameters of at least two drill bits (1) based on the machining parameters of the drill bit (1), the optimal drill bit (1) is determined based on the score, including the following steps: Among all the drill bits (1) with P > P1, the drill bit (1) represented by the largest P is the optimal drill bit (1). P1 is a predetermined known value and P1 > 0.

9. The method for evaluating the cutting performance of a drill bit according to any one of claims 1 to 5, characterized in that, The acquisition of drilling parameters during the drilling simulation process includes: Obtain the drilling parameters during the drilling simulation process from the start of the rotation of the drill bit (1) to the rotation of the drill bit (1) at a preset angle; Or, the drilling parameters in the drilling simulation process, which are the duration of the continuous rotation of the drill bit (1) to a preset duration.

10. A drill bit cutting performance evaluation device, characterized in that, include: The machining parameter module is used to obtain the machining parameters of the drill bit (1), which include the spindle speed, feed rate, drilling depth and hole diameter of the drill bit (1); The drill bit parameter determination module is used to determine the design parameters of at least one drill bit (1) based on the processing parameters, and generate a three-dimensional model of the drill bit (1) based on the design parameters. The design parameters of the drill bit (1) include the drill tip angle, the first back face angle, the second back face angle, the outer diameter of the drill bit (1), the core thickness of the drill bit (1), the core thickness taper, the helix angle, the cutting edge length, and the groove length. The workpiece simulation module is used to generate a three-dimensional model of the workpiece (2) based on the machining parameters of the drill bit (1) and the design parameters of the drill bit (1); The drilling simulation module is used to assemble the three-dimensional model of the drill bit (1) onto the three-dimensional model of the workpiece (2), and control the three-dimensional model of the drill bit (1) to perform drilling simulation on the three-dimensional model of the workpiece (2) according to the spindle speed and feed speed in the machining parameters. The drilling parameter acquisition module is used to acquire the drilling parameters of the drill bit (1) during the drilling simulation process. The drilling parameters include cutting force, cutting torque and maximum stress. The performance evaluation module is used to evaluate the drill bit (1) based on the obtained drilling parameters.

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