Design method of rough-finish combined integrated tooth cutter, cutter designed thereby and use method thereof

Abstract

The application discloses a design method of a rough-fine composite integrated gear turning cutter, a cutter designed by the method and a use method of the cutter, wherein the cutter comprises a cylindrical rough machining part and a conical fine machining part coaxially assembled on a cutter shaft; the cylindrical rough machining part is located at the front end of the cutter shaft and is used for rough gear turning machining of an internal gear workpiece; the cylindrical rough machining part is free of a structural clearance angle and is used for rough machining in a spatial pose with a non-zero installation inclination angle; the conical fine machining part is located at the rear end of the cutter shaft and is used for fine gear turning machining of the internal gear workpiece; the conical fine machining part is used for fine machining based on a pose without an installation inclination angle; and the tooth profile size of the cylindrical rough machining part is smaller than that of the conical fine machining part.

Description

Technical Field

[0001] This invention relates to the field of gear manufacturing technology, specifically to a design method for a roughing and finishing composite gear turning tool, as well as the designed tool and its usage method. Background Technology

[0002] As a core component of mechanical transmission systems, the machining accuracy of gears directly affects transmission efficiency and noise levels. Gear turning technology, as a highly efficient method for machining internal gears, has been widely used in recent years.

[0003] In actual production, to ensure the final tooth surface accuracy, gear turning is usually divided into two processes: roughing and finishing. Roughing removes most of the excess material, resulting in severe tool wear. Finishing uses a small amount of chips to achieve a high-precision tooth surface. Current processes often use different tools or machine tools to complete roughing and finishing separately, which leads to the following problems:

[0004] Secondary clamping error: After rough machining, the workpiece needs to be re-clamped and positioned before finishing. The two clamping inevitably introduces positioning deviation, which affects the tooth profile accuracy and batch consistency. Especially in situations where strict control of finishing allowance is required, this error will directly reduce the finished product qualification rate.

[0005] Low production efficiency: Process separation leads to multiple loading and unloading of workpieces and multiple adjustments of machine tools, which increases auxiliary time and equipment occupation, making it difficult to meet the needs of high-efficiency manufacturing.

[0006] Difficulty in achieving both cutting tool performance: Existing single-configuration gear cutting tools cannot simultaneously meet the heavy-load wear resistance requirements of the roughing stage and the high-precision cutting requirements of the finishing stage. For example, although cylindrical gear cutting tools are easy to regrind and have good cutting edge shape retention, they have no structural clearance angle and must be installed at an angle during machining (introducing an installation tilt angle), which disrupts the standard meshing kinematics and results in low theoretical machining accuracy. On the other hand, although conical gear cutting tools can achieve high-precision non-tilt cutting through structural clearance angles, their cutting edge shape changes with regrinding and cannot withstand the severe wear during the roughing stage.

[0007] Therefore, there is an urgent need for a gear cutting tool that can complete the process from roughing to finishing in one operation and one clamping, ensuring the accuracy of the cutting edge shape after roughing and regrinding, and providing precise and uniform small allowances for finishing, thereby achieving efficient and high-precision internal gear manufacturing. Summary of the Invention

[0008] The purpose of this invention is to provide a design method for a roughing and finishing composite gear turning tool, as well as the designed tool and its usage method, to at least solve the problems of secondary clamping errors, low production efficiency, and difficulty in achieving both tool performance and accuracy in gear machining.

[0009] To solve the above-mentioned technical problems, in a first aspect, the present invention provides a design method for a roughing and finishing composite integrated gear turning tool, comprising the following steps:

[0010] S1: Establish the three-dimensional tooth surface equation of the target workpiece. ;

[0011] S2: Establish the target workpiece coordinate system S w And the three-dimensional tooth surface equation From the target workpiece coordinate system S w After comprehensive transformation matrix Transformation yields the tool coordinate system S c The coordinate transformation equation is obtained. ;

[0012] S3: Construct the meshing equation, and solve the roughing conjugate surface equation with installation tilt angle and the finishing standard conjugate surface equation without installation tilt angle by simultaneously solving the coordinate transformation equation and the meshing equation;

[0013] S4: Establish the rake face model, and combine the rake face model with the roughing conjugate surface equation and the meshing equation to solve for the spatial discrete points of the roughing cutting edge; at the same time, combine the rake face model with the finishing standard conjugate surface equation and the meshing equation to solve for the spatial discrete points of the finishing cutting edge.

[0014] S5: By changing the position of the rake face in the spatial coordinate system, the size of the roughing cutting edge is changed, so that the profile of the roughing cutting edge is smaller than that of the finishing cutting edge.

[0015] S6: The roughing cutting edge obtained in step S5 is subjected to a cylindrical helical lifting motion to generate a cylindrical roughing part model; the finishing cutting edge is subjected to a conical helical lifting motion to generate a conical finishing part model; then the cylindrical roughing part model and the conical finishing part model are combined along the axial direction to obtain a roughing and finishing integrated turning gear tool model.

[0016] Furthermore, the three-dimensional tooth profile equation of the target workpiece The construction methods include:

[0017] Establish the two-dimensional tooth profile equation of the internal gear in a two-dimensional coordinate system;

[0018] The two-dimensional tooth profile equation is transformed by helical motion to generate the three-dimensional tooth profile equation of the internal gear. .

[0019] Furthermore, the comprehensive transformation matrix The expression is:

[0020] ;

[0021] in, This represents the transformation matrix describing the rotational motion of the target workpiece about its own axis. This represents the spatial position transformation matrix describing the intersection angle and center distance of the axes. This represents the transformation matrix describing the adjustment of the installation tilt angle attitude. This represents the transformation matrix describing the rotary motion of the cutting tool.

[0022] Furthermore, center distance The calculation method is as follows:

[0023] When calculating the conjugate surface of the roughing turning cutter, i.e., when adjusting the attitude to avoid interference with the mounting angle, the center distance is corrected according to the mounting angle k, expressed as:

[0024] ;

[0025] When calculating the conjugate surface of the finishing turning cutter, the mounting tilt angle is set to zero, meaning no adjustment is made to the mounting tilt angle posture, and the center distance is the standard mounting center distance, expressed as:

[0026] ;

[0027] in, , These are the center distances when the tilt angle is not installed and when the tilt angle is installed, respectively. , These are the pitch circle radii of the target workpiece and the cutting tool, respectively.

[0028] Furthermore, the solution method for the rough-machined conjugate surface equation with installation tilt angle includes: substituting the preset non-zero installation tilt angle into the transformation matrix chain, combining it with the corrected center distance, and simultaneously solving the meshing equations. The conjugate tooth surface of the cutting tool with the installation tilt angle is obtained.

[0029] Furthermore, the solution method for the standard conjugate surface equation of finishing without installation tilt angle includes: setting the installation tilt angle to zero, substituting into the transformation matrix chain, and combining the corrected center distance to simultaneously solve the meshing equations. The equation of the standard conjugate surface for finishing without installation tilt angle is obtained.

[0030] Furthermore, the meshing equation is based on the normal vector at the meshing point. With relative motion velocity vector With the perpendicular condition established, the expression for the meshing equation is:

[0031] .

[0032] Furthermore, the equation of the rake face is a spatial plane equation.

[0033] In a second aspect, the present invention provides a roughing and finishing integrated gear cutting tool designed by the design method mentioned in the first aspect above, comprising a cylindrical roughing part and a conical finishing part coaxially assembled on the tool shaft;

[0034] The cylindrical roughing section is located at the front end of the cutter shaft and is used for heavy-duty roughing of internal gear workpieces. The cylindrical roughing section has no structural back angle and performs roughing in a spatial pose with a non-zero installation tilt angle.

[0035] The conical finishing section is located at the rear end of the cutter shaft and is used for finishing the internal gear workpiece. The conical finishing section performs finishing based on a position without an installation tilt angle. Furthermore, the tooth profile size of the cylindrical roughing section is smaller than that of the conical finishing section.

[0036] Thirdly, the present invention provides a method of using the cutting tool as mentioned in the second aspect above, comprising:

[0037] Roughing stage: The machine tool spindle drives the tool to tilt at a preset installation angle, so that the cylindrical roughing part at the front end of the tool cuts into the workpiece for heavy-duty gear turning roughing, in order to avoid interference between the cylindrical roughing part itself and the workpiece, as well as interference between the conical finishing part at the rear end of the tool and the workpiece.

[0038] Finishing stage: The machine tool spindle is centered to eliminate the installation tilt angle. The tool is fed axially so that the conical finishing part at the rear end of the tool cuts into the workpiece for finishing gear turning based on the roughing. At this time, the conical finishing part relies on its structural back angle to perform high-precision cutting and uses its own structural back angle to avoid geometric interference between the front roughing part and the workpiece.

[0039] The beneficial effects of this invention are as follows:

[0040] 1. By employing the spatial meshing principle and coordinate transformation matrix, the conjugate tooth surface is solved for both states with and without installation tilt angles, and the cutting edge size is controlled by adjusting the position of the rake face. This method is applicable to the design of various internal gear turning tools with different modules, numbers of teeth, and helix angles, and has good engineering application value. By adjusting the axial position of the rake face in the spatial coordinate system, the cutting edge profile of the cylindrical roughing part is made smaller than that of the conical finishing part. During the finishing stage, even if the conical finishing part cuts into the workpiece with no tilt angle, the cylindrical roughing part at the front end will not interfere with the already rough-machined tooth surface, ensuring the safety of the entire machining process.

[0041] 2. By integrating roughing and finishing functions into the same tool axis to form an integrated tool, heavy-duty roughing and high-precision finishing can be completed in a single clamping and the same process. This avoids installation and repositioning errors caused by secondary clamping, enabling precise control of small allowances. It also reduces the number of workpiece loading and unloading operations, improving production efficiency. Furthermore, by using a cylindrical toothed cutter configuration for the roughing section, which bears most of the cutting load and wear, the cylindrical toothed cutter can maintain its cutting edge accuracy even after frequent regrinding during the heavy-load and wear-prone roughing stage, reserving precise allowances for finishing. This allows for precise control of small allowances and ensures that the cutting load of the conical toothed cutter is small during the finishing stage, reducing tool wear. Attached Figure Description

[0042] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, use the same reference numerals to denote the same or similar parts. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0043] Figure 1 Design a flowchart of the method steps;

[0044] Figure 2 This is an exploded view of a roughing and finishing composite integrated gear cutting tool of the present invention;

[0045] Figure 3 This is a three-dimensional structural schematic diagram of a roughing and finishing composite integrated gear cutting tool according to the present invention;

[0046] Figure 4 This is a schematic diagram illustrating the roughing and finishing process of a composite gear turning tool according to the present invention.

[0047] Figure 5 This is a comparison diagram of the roughing and finishing gear cutting tools of the present invention;

[0048] Figure 6 This is a comparison diagram of the roughing and finishing cutting edges of a composite gear turning tool according to the present invention.

[0049] The components include: 1. Cylindrical roughing section; 2. Conical finishing section; 3. Tool shaft; 4. Washer. Detailed Implementation

[0050] like Figure 1 The design method of the roughing and finishing integrated gear turning tool shown includes the following steps:

[0051] S1: Establish the three-dimensional tooth surface equation of the target workpiece. ;

[0052] S2: Establish the target workpiece coordinate system S w And the three-dimensional tooth surface equation From the target workpiece coordinate system S w After comprehensive transformation matrix Transformation yields the tool coordinate system S c The coordinate transformation equation is obtained. ;

[0053] S3: Construct the meshing equation, and solve the roughing conjugate surface equation with installation tilt angle and the finishing standard conjugate surface equation without installation tilt angle by simultaneously solving the coordinate transformation equation and the meshing equation;

[0054] S4: Establish the rake face model, and combine the rake face model with the roughing conjugate surface equation and the meshing equation to solve for the spatial discrete points of the roughing cutting edge; at the same time, combine the rake face model with the finishing standard conjugate surface equation and the meshing equation to solve for the spatial discrete points of the finishing cutting edge.

[0055] S5: By changing the position of the rake face in the spatial coordinate system, the size of the roughing cutting edge is changed, so that the profile of the roughing cutting edge is smaller than that of the finishing cutting edge.

[0056] S6: Perform a cylindrical helical lifting motion on the roughing cutting edge obtained in step S5 to generate a cylindrical roughing part 1 model, as shown. Figure 5 As shown in (b); the finishing cutting edge is subjected to a conical spiral lifting motion to generate a conical finishing part 2 model, as shown in the figure. Figure 5 As shown in (a); then the cylindrical roughing part 1 model and the conical finishing part 2 model are combined along the axial direction to obtain the roughing and finishing integrated turning gear tool model.

[0057] This method employs a spatial meshing principle and coordinate transformation matrix to solve for the conjugate tooth surface under both installation tilt angle and no installation tilt angle conditions, and controls the cutting edge size by adjusting the position of the rake face. This method is applicable to the design of various internal gear turning tools with different modules, numbers of teeth, and helix angles, and has good engineering application value. By adjusting the axial position of the rake face in the spatial coordinate system, the cutting edge profile of the cylindrical roughing part 1 is made smaller than that of the conical finishing part 2. During the finishing stage, even if the conical finishing part 2 cuts into the workpiece with no tilt angle, the front end of the cylindrical roughing part 1 will not interfere with the already rough-machined tooth surface, ensuring the safety of the entire machining process.

[0058] According to one embodiment of this application, the three-dimensional tooth profile equation of the target workpiece is... The construction methods include:

[0059] Establish the two-dimensional tooth profile equation of the internal gear in a two-dimensional coordinate system;

[0060] The two-dimensional tooth profile equation is transformed by helical motion to generate the three-dimensional tooth profile equation of the internal gear. .

[0061] According to one embodiment of this application, the comprehensive transformation matrix... The expression is:

[0062] ;

[0063] Among them, among them, The transformation matrix describing the rotational motion of the target workpiece about its own axis is represented as:

[0064] ;

[0065] The spatial position transformation matrix describing the intersection angle and center distance of the axes is represented as follows:

[0066] ;

[0067] The transformation matrix describing the installation tilt attitude adjustment is represented as:

[0068] ;

[0069] The transformation matrix describing the rotary motion of the cutting tool is represented as follows:

[0070] .

[0071] According to one embodiment of this application, the rotation angle of the target workpiece rotating about its own axis is... The rotation angle of the cutting tool about its own axis The relational expression is:

[0072] ;

[0073] in, Let be the rotation angle of the target workpiece rotating about its own axis. These are the rotation angles of the cutting rotation of the gear cutting cutter. , These represent the number of teeth on the cutting tool and the target workpiece, respectively.

[0074] According to one embodiment of this application, the formula for calculating the axial angle is:

[0075] ;

[0076] in, , These are the helix angles of the cutting tool and the target workpiece, respectively.

[0077] According to one embodiment of this application, the center distance The calculation method is as follows:

[0078] When calculating the conjugate surface of the roughing turning cutter, i.e., when adjusting the attitude to avoid interference with the mounting angle, the center distance is corrected according to the mounting angle k, expressed as:

[0079] ;

[0080] When calculating the conjugate surface of the finishing turning cutter, the mounting tilt angle is set to zero, meaning no adjustment is made to the mounting tilt angle posture, and the center distance is the standard mounting center distance, expressed as:

[0081] ;

[0082] in, , These are the center distances when the tilt angle is not installed and when the tilt angle is installed, respectively. , These are the pitch circle radii of the target workpiece and the cutting tool, respectively.

[0083] According to one embodiment of this application, the method for solving the equation of a rough-machined conjugate surface with an installation tilt angle includes: setting a preset non-zero installation tilt angle (e.g., ... Substituting into the transformation matrix chain and combining it with the corrected center distance, we can simultaneously solve the meshing equations. The conjugate tooth surface of the cutting tool with the installation tilt angle is obtained.

[0084] This embodiment addresses the characteristic of cylindrical cutting tools lacking structural back angles by introducing a reasonable installation tilt angle. This creates an additional tilt of the tool axis relative to the workpiece, geometrically preventing interference between the cylindrical roughing section 1 and the workpiece, as well as interference between the rear conical finishing section 2 and the workpiece. This posture adjustment is simple and reliable, achieving collision-free cutting without altering the tool structure.

[0085] According to one embodiment of this application, the method for solving the equation of the standard conjugate surface of a finishing surface without an installation tilt angle includes: setting the installation tilt angle to zero ( Substituting into the transformation matrix chain and combining it with the corrected center distance, we can solve the meshing equations simultaneously. The equation of the standard conjugate surface for finishing without installation tilt angle is obtained.

[0086] In the finishing stage, a conical finishing section 2 is used, and the installation tilt angle is set to zero. The standard meshing cutting without interference is performed by utilizing the structural back angle of the conical tool. Compared with the existing cylindrical gear cutting tool, which requires machining with an installation tilt angle and introduces a fundamental error, this invention reduces the theoretical machining error caused by the installation tilt angle and ensures the high precision and consistency of the internal gear tooth profile.

[0087] According to one embodiment of this application, the meshing equation is based on the normal vector at the meshing point. With relative motion velocity vector With the perpendicular condition established, the expression for the meshing equation is:

[0088] .

[0089] According to one embodiment of this application, the rake face equation This is the equation of the spatial plane.

[0090] Secondly, the present invention provides a roughing and finishing integrated gear turning tool designed using the design method mentioned in the first aspect above, such as... Figure 2 and Figure 3 As shown, it includes a cylindrical roughing section 1 and a conical finishing section 2 coaxially assembled on the cutter shaft 3;

[0091] The cylindrical roughing section 1 is located at the front end of the cutter shaft 3 and is used for heavy-duty roughing of internal gear workpieces. The cylindrical roughing section 1 has no structural back angle and performs roughing in a spatial pose with a non-zero installation tilt angle.

[0092] The conical finishing section 2 is located at the rear end of the cutter shaft 3 and is used to perform gear finishing on the internal gear workpiece. The conical finishing section 2 performs finishing based on a position without an installation tilt angle. Furthermore, the tooth profile size of the cylindrical roughing section 1 is smaller than the tooth profile size of the conical finishing section 2.

[0093] This embodiment integrates a cylindrical roughing cutting cutter and a conical finishing cutting cutter into one unit. This avoids installation and repositioning errors caused by secondary clamping, enabling precise control of small allowances. It also reduces the number of workpiece loading and unloading operations, improving production efficiency. Furthermore, by using a cylindrical cutting cutter configuration for the roughing section, which bears most of the cutting load and wear, the cylindrical cutting cutter maintains its cutting edge accuracy even after frequent regrinding during the heavy-load, wear-prone roughing stage, reserving precise allowances for finishing. This allows for precise control of small allowances and ensures that the conical cutting cutter experiences low cutting loads during finishing, reducing tool wear.

[0094] The roughing and finishing functions are integrated into the same tool axis to form a one-piece tool. In a single clamping and the same operation, heavy-duty roughing and high-precision finishing of gears are completed successively. This eliminates the positioning errors and auxiliary time caused by the need to change tools and reclamp the workpiece after roughing in traditional processes. Furthermore, by using a cylindrical gear cutting tool configuration for the roughing section, which bears most of the cutting load and wear, the tooth profile along its axial section is consistent, and the cutting edge shape remains unchanged after multiple regrindings of the rake face. The conical finishing section 2 is only used for the finishing stage with very small cutting allowances, and wear is minimal, requiring almost no regrinding. Therefore, this tool not only utilizes the high-precision machining capability of conical tools but also completely avoids the technical bottleneck of edge shape changes caused by regrinding, significantly extending the overall service life of the tool.

[0095] Thirdly, the present invention provides a method of using the cutting tool as mentioned in the second aspect above, such as... Figure 4 As shown, it includes:

[0096] Roughing stage: The machine tool spindle drives the tool to tilt at a preset installation angle, so that the cylindrical roughing part 1 at the front end of the tool cuts into the workpiece for heavy-duty gear turning roughing, so as to avoid interference between the cylindrical roughing part 1 and the workpiece, as well as interference between the conical finishing part 2 at the rear end of the tool and the workpiece.

[0097] Finishing stage: The machine tool spindle is rectified to eliminate the installation tilt angle. The tool is fed along the axis so that the conical finishing part 2 at the rear end of the tool cuts into the workpiece for finishing gear turning on the basis of roughing. At this time, the conical finishing part 2 relies on its structural back angle to perform high-precision cutting and uses its own structural back angle to avoid geometric interference between the front roughing part and the workpiece.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A design method for a roughing and finishing composite integrated gear turning tool, characterized in that, Includes the following steps: S1: Establish the three-dimensional tooth surface equation of the target workpiece. ; S2: Establish the target workpiece coordinate system S w and the three-dimensional tooth surface equation From the target workpiece coordinate system S w After comprehensive transformation matrix Transformation yields the tool coordinate system S c The coordinate transformation equation is obtained. ; S3: Construct the meshing equation, and solve the roughing conjugate surface equation with installation tilt angle and the finishing standard conjugate surface equation without installation tilt angle by simultaneously solving the coordinate transformation equation and the meshing equation. S4: Establish a rake face model, and combine the rake face model with the roughing conjugate surface equation and the meshing equation to solve for the spatial discrete points of the roughing cutting edge; at the same time, combine the rake face model with the finishing standard conjugate surface equation and the meshing equation to solve for the spatial discrete points of the finishing cutting edge. S5: By changing the position of the rake face in the spatial coordinate system, the size of the roughing cutting edge is changed, so that the profile of the roughing cutting edge is smaller than that of the finishing cutting edge. S6: The roughing cutting edge obtained in step S5 is subjected to a cylindrical helical lifting motion to generate a cylindrical roughing part model; the finishing cutting edge is subjected to a conical helical lifting motion to generate a conical finishing part model; then the cylindrical roughing part model and the conical finishing part model are combined along the axial direction to obtain a roughing and finishing integrated turning gear tool model.

2. The design method according to claim 1, characterized in that, The three-dimensional tooth profile equation of the target workpiece The construction methods include: Establish the two-dimensional tooth profile equation of the internal gear in a two-dimensional coordinate system; The two-dimensional tooth profile equation is transformed by helical motion to generate the three-dimensional tooth profile equation of the internal gear. .

3. The design method according to claim 2, characterized in that, The comprehensive transformation matrix The expression is: ； in, This represents the transformation matrix describing the rotational motion of the target workpiece about its own axis. This represents the spatial position transformation matrix describing the intersection angle and center distance of the axes. This represents the transformation matrix describing the adjustment of the installation tilt angle attitude. This represents the transformation matrix describing the rotary motion of the cutting tool.

4. The design method according to claim 3, characterized in that, The center distance The calculation method is as follows: When calculating the conjugate surface of the roughing turning cutter, i.e., when adjusting the attitude to avoid interference with the mounting angle, the center distance is corrected according to the mounting angle k, expressed as: ； When calculating the conjugate surface of the finishing turning cutter, the mounting tilt angle is set to zero, meaning no adjustment is made to the mounting tilt angle posture, and the center distance is the standard mounting center distance, expressed as: ； in, , These are the center distances when the tilt angle is not installed and when the tilt angle is installed, respectively. , These are the pitch circle radii of the target workpiece and the cutting tool, respectively.

5. The design method according to claim 4, characterized in that, The method for solving the equation of the rough-machined conjugate surface with the installation tilt angle includes: substituting the preset non-zero installation tilt angle into the transformation matrix chain, combining it with the corrected center distance, and simultaneously solving the meshing equation. The conjugate tooth surface of the cutting tool with the installation tilt angle is obtained.

6. The roughing and finishing composite gear cutting tool according to claim 4, characterized in that, The solution method for the standard conjugate surface equation of the finishing process without installation tilt angle includes: setting the installation tilt angle to zero, substituting into the transformation matrix chain, and combining the corrected center distance to simultaneously solve the meshing equations. The equation of the standard conjugate surface for finishing without installation tilt angle is obtained.

7. The roughing and finishing composite gear cutting tool according to claim 1, characterized in that, The meshing equation is based on the normal vector at the meshing point. With relative motion velocity vector With the perpendicular condition established, the expression for the meshing equation is: 。 8. The roughing and finishing composite gear cutting tool according to claim 1, characterized in that, The equation of the rake face is a spatial plane equation.

9. A roughing and finishing composite gear cutting tool designed by the design method according to any one of claims 1-8, characterized in that, It includes a cylindrical roughing section and a conical finishing section coaxially assembled on the cutter shaft; The cylindrical roughing section is located at the front end of the cutter shaft and is used for heavy-duty roughing of internal gear workpieces; the cylindrical roughing section has no structural back angle and performs roughing in a spatial pose with a non-zero installation tilt angle; The conical finishing section is located at the rear end of the cutter shaft and is used for finishing the internal gear workpiece. The conical finishing section performs finishing based on a position without an installation tilt angle. Furthermore, the tooth profile size of the cylindrical roughing section is smaller than that of the conical finishing section.

10. A method of using the knife as described in claim 9, characterized in that, include: Roughing stage: The machine tool spindle drives the tool to tilt at a preset installation angle, so that the cylindrical roughing part at the front end of the tool cuts into the workpiece for heavy-duty gear turning roughing, so as to avoid interference between the cylindrical roughing part itself and the workpiece, as well as interference between the conical finishing part at the rear end of the tool and the workpiece. Finishing stage: The machine tool spindle is centered to eliminate the installation tilt angle. The tool is fed axially so that the conical finishing part at the rear end of the tool cuts into the workpiece for finishing gear turning based on the roughing. At this time, the conical finishing part relies on its structural back angle to perform high-precision cutting and uses its own structural back angle to avoid geometric interference between the front roughing part and the workpiece.

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