Tooth turning blade part gradual change passivation amount calculation and control method

Abstract

The invention discloses a method for calculating and controlling the gradual change passivation amount of a tooth turning blade part. The method comprises the following steps: step 1, determining the minimum passivation fillet value of a tooth turning cutter according to the material type of the tooth turning cutter and the tensile strength of a processed workpiece material; 2, according to the total cutting frequency of the tooth turning cutter for machining a workpiece, the maximum passivation fillet coefficient of the edge of the tooth turning cutter is determined; then the maximum passivation fillet value of the tooth turning blade part is calculated; step 3, selecting a passivated fillet of a part between a tooth root part and a tooth top part of the tooth turning blade part, wherein passivated fillet values are continuously distributed between the minimum passivated fillet value and the maximum passivated fillet value of the tooth turning blade part; and step 4, keeping the passivated side length ratio K of the front and rear cutter surfaces of the passivated amount of the tooth turning blade part unchanged along with the passivated radius. According to the method, the purpose of quantifying the passivation amount of the gear turning cutter can be achieved, and the problem that the passivation amount of the gear turning cutter cannot adaptively adjust the machining working condition and machining parameters in the current industry is solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of cutting tools for machining, and relates to a tooth turning tool blade portion gradual change passivation amount calculation and control method. BACKGROUND

[0002] As a core tool for high-precision gear machining, the blade quality of the tooth turning tool directly affects the machining efficiency and tool life. The traditional sharpening process leaves microscopic notches (such as broken blade, sawtooth pattern, etc.) at the blade edge. These defects can easily expand in high-speed cutting or intermittent machining, leading to rapid tool failure and reduced workpiece machining surface quality. In recent years, with the development of tooth turning machining towards high-speed machining and automation, the industry has significantly increased the requirements for the stability and durability of tooth turning tools, especially for the mass production of medium-hardness inner gear ring machining. Passivation, as a key pretreatment step in tool manufacturing and sharpening, can significantly improve the cutting performance of the tool and reduce frictional heat, and has become a standardized process in modern tool manufacturing.

[0003] The current mainstream passivation technologies in the industry include grinding wheel passivation, nylon brush passivation, and sandblasting passivation. These different passivation methods currently have the following problems: 1) no distinction in adaptability to working conditions, different tool materials and workpiece materials have different sensitivities to passivation degree; 2) no adaptability to machining parameter conditions, different cutting parameters have different demands for tool blade passivation; 3) no clear passivation amount control method, only simple 0.01-0.04mm passivation fillet evaluation and measurement, the evaluation standard is too rough and cannot achieve the purpose of stability control.

[0004] Tooth turning machining is a precision gear machining method, and the passivation of the tooth turning tool blade portion has a very significant impact on the precision, roughness of tooth turning machining and the machining life of the tooth turning tool itself. The larger the blade portion passivation value, the better the strength and longer the life of the tool, but the worse the machining precision and tooth surface roughness. Conversely, the smaller the blade portion passivation value, the better the machining precision and roughness, but the worse the blade retention and the shorter the tool life, resulting in higher machining cost. Therefore, the setting of the passivation amount in tooth turning tool passivation (tooth turning tool passivation amount includes two indexes: passivation fillet and front and rear blade surface edge length ratio) is a key index. However, there is no standard for tooth turning tool passivation amount in the industry, and there is no adaptive adjustment to machining conditions and machining parameters. Therefore, it is necessary to study a tooth turning tool blade portion gradual change passivation amount calculation and control method. SUMMARY

[0005] The purpose of the present application is to provide a tooth turning tool blade portion gradual change passivation amount calculation and control method to solve the problem of no adaptive adjustment of tooth turning tool passivation amount to machining conditions and machining parameters in the current industry.

[0006] In order to achieve the above object, the present application adopts the following technical solutions to solve the above problems: In the first aspect, the present application provides a kind of tooth cutter blade section gradual change passivation quantity calculation and control method, comprising the following steps: Step 1, according to the material type A of the used gear cutter and the tensile strength Rm of the machined workpiece material, determine the minimum passivation fillet value R0 of the used gear cutter, corresponding to the passivation fillet value of the tooth root part of gear cutter blade section; Step 2, according to the total cutting frequency N of the gear cutter for processing a workpiece, determine the maximum passivation fillet coefficient T of the gear cutter blade section;Then calculate the maximum passivation fillet value R of the gear cutter blade section max =R0*T, corresponding to the passivation fillet value of the tooth top part of gear cutter blade section; Step 3, the selection of passivation fillet between the tooth root part and the tooth top part of gear cutter blade section: the passivation fillet value is continuously distributed between the minimum passivation fillet value R0 and the maximum passivation fillet value R max of the gear cutter blade section; Step 4, the passivation length ratio K of the front and rear tool faces of the passivation amount of the gear cutter blade section remains unchanged with the passivation radius.

[0007] Further, in step 1, the basic passivation fillet R0 of the used gear cutter is determined as follows: (1) when Rm≤750 N / mm 2 , ① if A is powder metallurgy high steel, R0=0.012mm;② if A is hard alloy, R0=0.018mm; (2) when 750 N / mm 2 <Rm≤900 N / mm 2 , ① if A is powder metallurgy high steel, R0=0.015mm;② if A is hard alloy, R0=0.022mm; (3) when 900 N / mm 2 <Rm≤1100 N / mm 2 , ① if A is powder metallurgy high steel, R0=0.018mm;② if A is hard alloy, R0=0.025mm; (4) when Rm>1100 N / mm 2 , ① if A is powder metallurgy high steel, not applicable;② if A is hard alloy, R0=0.022mm.

[0008] Further, in step 2, the maximum passivation fillet coefficient T of the gear cutter blade section is determined as follows: (1) when N≤6, T=1.0; (2) when 6 (3) 10 < N < 14, T = 1.4; (4) N < 14, T = 1.6.

[0009] Further, in step 4, K takes a value of 1~1.1.

[0010] In a second aspect, the present application provides an electronic device, comprising: a memory for storing executable instructions; a processor for executing the executable instructions or computer programs stored in the memory to implement the method provided in the first aspect of the present application.

[0011] In a third aspect, the present application provides a computer readable storage medium storing executable instructions or computer programs, which are executed by a processor to implement the method provided in the first aspect of the present application.

[0012] Compared with the prior art, the present application has the following advantages: 1. According to the present application, the distribution of the blade part of the gear cutting tool is determined according to the number of cutting times at different positions, and the gradual blunting makes the relative wear rate of the entire blade part of the gear cutting tool consistent. Compared with consistent blunting or no blunting, the fHa error caused by the gradual wear of the gear cutting tool is significantly reduced, and the service life of the gear cutting tool is prolonged.

[0013] 2. According to the present application, the reference blunted corner is determined according to the machining conditions (i.e. the tensile strength of the workpiece and the material of the gear cutting tool). The present application clearly defines the basic blunting standard of the blade part of the gear cutting tool, so that the blunting standard is clear and can be used as a basis, and good blunting use effect can be obtained under different conditions.

[0014] 3. According to the present application, the maximum blunted corner of the gear cutting tool is determined according to the maximum number of cutting times. The maximum blunted corner is distributed near the tool tip, which is the fastest wearing part of the gear cutting tool. By using the maximum blunted amount, the characteristics of the tool tip not participating in the generation of the effective tooth profile of the involute can be fully utilized. The large blunted amount can not only affect the machining precision, but also significantly slow down the wear rate of the tool tip part, thereby increasing the service life of the tool.

[0015] In summary, the method of the present application can achieve the purpose of quantifying the blunted amount of the gear cutting tool, and solve the problem that the blunted amount of the gear cutting tool has no adaptive adjustment to the machining conditions and machining parameters in the current industry. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a schematic diagram of the cutting amount distribution of the blade part of the gear cutting tool; Figure 2 is a schematic diagram of the blunted length Lf of the rake face and the blunted length Lb of the relief face on the cross section of the blade part of the gear cutting tool Figure 3Distribution diagram of the passivation amount of the toothed cutter blade part; Figure 4 Distribution diagram of the passivation amount of the toothed cutter blade part from the tooth root to the tooth top; Figure 5 Superimposed diagram of the passivation fillet values of each section.

[0017] The scheme of the present application is further explained in the following in combination with the drawings and specific embodiments. Specific Embodiments

[0018] The main principle of the technical scheme adopted by the present application is as follows: 1. According to the tensile strength of the workpiece material to be machined and the material type of the toothed cutter used, the basic passivation fillet value R0 of the toothed cutter blade part is determined. The higher the tensile strength of the workpiece material, and the worse the impact toughness of the cutter material, the more prominent the adverse factors of low blade strength and low life of the toothed cutter, at this time, the basic passivation fillet value of the toothed cutter blade part should be selected to be larger, and the cutting sharpness and machining precision should be appropriately sacrificed to enhance the strength of the cutter blade part to improve the problem of low strength and low life. The lower the tensile strength of the workpiece material, and the better the impact toughness of the cutter material, the smaller the basic passivation fillet value of the toothed cutter blade part should be selected to improve the cutting sharpness and machining precision of the blade part without significantly affecting the blade life. According to the experience of toothed cutter machining, in order to balance the contradiction between the strength of the toothed cutter blade part and the machining precision, the basic passivation fillet value R0 of the toothed cutter blade part is determined according to Table 1.

[0019] Table 1: Selection table of basic passivation fillet value R0 of toothed cutter blade part (passivation fillet value unit: mm, tensile strength unit: N / mm 2 )

[0020] 2. According to the cutting frequency in the machining parameters, the maximum passivation fillet value R of the toothed cutter blade part is determined. max ; The toothed cutter machining has the characteristics of many times and small cutting depth, the cutting frequency of the cutter tooth root part is the least, generally only once, the cutting frequency of the tooth top is the most (determined according to the machining parameters), the total cutting frequency of different positions of the blade part is inconsistent, the total cutting frequency of the cutter top is the most, the cutter tooth root is the least, and the middle position gradually transitions, which is approximately distributed as shown in Figure 1 According to the cutting frequency in Table 2, the maximum passivation fillet calculation coefficient T is selected. The maximum passivation fillet value R max =T*R0.

[0021] Table 2: Maximum passivation amount coefficient T determined according to cutting parameters

[0022] Determine the basic passivation fillet value R0 and the maximum passivation fillet value R of the cutting edge of the gear. max Then, combining the industry-standard passivation amount with the ratio of the passivation edge length of the front and rear cutting faces, K=L f / L b L f L b These represent the front and rear face lengths of the gear cutting cutter, respectively (the ratio of the front and rear face lengths of a gear cutting cutter is generally K = 1~1.1), which allows for precise control of the gear cutting cutter's passivation. See [link to documentation]. Figure 2 .

[0023] The present invention provides a method for calculating and controlling the gradual passivation amount of the cutting edge of a turning tooth, comprising the following steps: Step 1: Based on the material type A of the cutting tool and the tensile strength Rm of the workpiece material, determine the minimum blunting fillet value R0 of the cutting tool, which corresponds to the blunting fillet value of the tooth root part of the cutting tool.

[0024] In a preferred embodiment of the present invention, the basic blunt fillet R0 of the gear cutting cutter is determined as follows: (1) When Rm≤750 N / mm 2 When: ① If A is powder metallurgy high-strength steel, R0 = 0.012mm; ② If A is cemented carbide, R0 = 0.018mm; (2) When 750 N / mm 2 <Rm≤900 N / mm 2 When: ① If A is powder metallurgy high-strength steel, R0 = 0.015mm; ② If A is cemented carbide, R0 = 0.022mm; (3) When 900 N / mm 2 <Rm≤1100 N / mm 2 When: ① If A is powder metallurgy high-strength steel, R0 = 0.018mm; ② If A is cemented carbide, R0 = 0.025mm; (4) When Rm>1100 N / mm 2 When: ① If A is powder metallurgy high-strength steel, it is not applicable; ② If A is cemented carbide, R0 = 0.022 mm.

[0025] Step 2: Determine the maximum blunting fillet coefficient T of the cutting edge of the gear cutting tool based on the total number of cutting operations N for machining one workpiece; then calculate the maximum blunting fillet value R of the cutting edge of the gear cutting tool. max =R0*T, which corresponds to the blunt fillet value of the tooth tip portion of the cutting edge.

[0026] In a preferred embodiment of the present invention, the maximum blunting fillet coefficient T of the cutting edge of the gear is determined as follows: (1) When N≤6, T=1.0; (2) When 6 < N ≤ 10, T = 1.2; (3) When 10 < N ≤ 14, T = 1.4; (4) When N < 14, T = 1.6.

[0027] Step 3, selection of the passivation fillet for the area between the tooth root and the tooth tip of the cutting edge: the minimum passivation fillet value R0 and the maximum passivation fillet value R on the cutting edge of the cutting edge. max Continuous distribution between them Figure 4 , Figure 5 As shown. Step 4: The ratio K of the passivation side lengths of the front and rear cutting faces of the passivation amount of the cutting tool remains constant with the passivation radius. Specifically, K takes a value of 1 to 1.1.

[0028] By using the blunt fillet obtained from the root portion to the tip portion of the cutting edge of the tooth-turning tool obtained in the present invention and K obtained in step 4, the control of the gradual blunting amount of the cutting edge of the tooth-turning tool can be completed.

[0029] To verify the feasibility and effectiveness of the method of the present invention, the following embodiments are provided.

[0030] In this embodiment, the parameters of a certain internal gear ring are as follows: module Mn2.117, pressure angle α20°, number of teeth Z91, helix angle 6°, and material tensile strength Rm1050. Gear cutting tool parameters: module Mn2.117, pressure angle α20°, number of teeth Z53, helix angle 9°, cemented carbide; like Figure 3 As shown, the root region of the cutting edge adopts a basic passivation amount, which gradually increases towards the tooth tip region of the cutting edge to the maximum passivation amount. The cutting parameters are shown in Table 3.

[0031] Table 3 Cutting parameters

[0032] Before this embodiment, the gear cutting cutter was not dulled, and the number of parts processed per sharpening session was 20-40, with a single tooth cutting length of 3-6 meters and a single tool cost of 28 yuan. The dulling parameters applied were: minimum root dulling radius of R0.025, maximum tip dulling radius of R0.025*1.4=R0.035, and rake / rare face side length ratio K=1. After application, the number of parts processed per sharpening session increased to 50-80, with a single cutting length of 8-12 meters, and the unit processing cost (including dulling cost) was 20 yuan / piece. The single processing life increased to (50+80) / (20+40)=216% of the original, and the single processing cost decreased by (1-20 / 28)=29%. Therefore, the method of this invention can effectively improve the processing life of gear cutting cutters and reduce production costs.

Claims

1. A method for calculating and controlling the gradual passivation amount of a turning tooth cutting edge, characterized in that, Includes the following steps: Step 1: Based on the material type A of the cutting tool and the tensile strength Rm of the workpiece material, determine the minimum passivation fillet value R0 of the cutting tool, which corresponds to the passivation fillet value of the tooth root part of the cutting tool. Step 2: Determine the maximum blunting fillet coefficient T of the cutting edge of the gear cutting tool based on the total number of cutting operations N for machining one workpiece; then calculate the maximum blunting fillet value R of the cutting edge of the gear cutting tool. max =R0*T, which corresponds to the blunt fillet value of the tooth tip part of the cutting edge of the turning tooth; Step 3, selection of the passivation fillet for the area between the tooth root and the tooth tip of the cutting edge: the minimum passivation fillet value R0 and the maximum passivation fillet value R on the cutting edge of the cutting edge. max Continuous distribution between them; Step 4: The ratio K of the passivation side lengths of the front and back face of the passivation amount of the cutting edge remains constant with the passivation radius.

2. The method for calculating and controlling the gradual passivation amount of the cutting edge of a turning tooth as described in claim 1, characterized in that, In step 1, the basic blunt fillet R0 of the gear cutting tool is determined as follows: (1) When Rm≤750 N / mm 2 When: ① If A is powder metallurgy high-strength steel, R0 = 0.012mm; ② If A is cemented carbide, R0 = 0.018mm; (2) When 750 N / mm 2 <Rm≤900 N / mm 2 When: ① If A is powder metallurgy high-strength steel, R0 = 0.015mm; ② If A is cemented carbide, R0 = 0.022mm; (3) When 900 N / mm 2 <Rm≤1100 N / mm 2 When: ① If A is powder metallurgy high-strength steel, R0 = 0.018mm; ② If A is cemented carbide, R0 = 0.025mm; (4) When Rm>1100 N / mm 2 When: ① If A is powder metallurgy high-strength steel, it is not applicable; ② If A is cemented carbide, R0 = 0.022 mm.

3. The method for calculating and controlling the gradual passivation amount of the cutting edge of a turning tooth as described in claim 2, characterized in that, In step 2, the maximum blunt fillet coefficient T of the cutting edge of the tooth is determined as follows: (1) When N≤6, T=1.0; (2) When 6 < N ≤ 10, T = 1.2; (3) When 10 < N ≤ 14, T = 1.4; (4) When N < 14, T = 1.

6.

4. The method for calculating and controlling the gradual passivation amount of the cutting edge of a turning tooth as described in any one of claims 1 to 3, characterized in that, In step 4, K takes the value from 1 to 1.

1.

5. An electronic device, characterized in that, The electronic device includes: Memory, used to store executable instructions; A processor, when executing executable instructions or computer programs stored in the memory, implements the method as described in claims 1 to 4.

6. A computer-readable storage medium storing executable instructions or a computer program, characterized in that, When the executable instructions are executed by the processor, they implement the method as described in any one of claims 1 to 4.

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