A method and system for efficiently and precisely machining the inner hole of high-hardness and high-strength gears

Abstract

The present invention discloses a method and system for efficiently and precisely machining the inner bore of a high-hardness, high-strength gear. The method incrementally increases the cutting area for machining the inner bore of the gear and collects the cutting force for each incremental increase in the cutting area. Multiple displacement change values ​​are calculated based on the multiple displacement change values. Multiple actual cutting depths are calculated based on the multiple actual cutting depths. Multiple actual cutting force coefficients are calculated based on the multiple actual cutting force coefficients. Multiple stable regions are calculated based on the multiple actual cutting force coefficients. The multiple stable regions are intersected to obtain a common stable region, and within the common stable region, the region with the maximum product of cutting depth and cutting speed is determined. Cutting parameters are determined within the region with the maximum product, and a torsion angle is calculated based on the cutting parameters. Based on the torsion angle, the actual installed tool rake angle and the actual installed tool clearance angle are calculated for machining the inner bore of the gear. The present invention can reduce tool wear, improve machining efficiency, and enhance workpiece quality.

Description

Technical Field

[0001] The present invention relates to the technical field of gear machining, and in particular to a method and system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear. Background Art

[0002] High-strength gears are widely used in aircraft engine transmission systems. To meet the requirements of high speeds, high load capacity, and high temperatures, high-strength gears require increasingly higher hardness and strength. These high-strength gears connect to the drive shaft through an inner bore. The dynamic high-frequency forces generated during gear meshing continuously impact the surface where the inner bore meets the shaft, placing higher demands on the shaft's shape, dimensional accuracy, microstructure, and contact properties. Traditional cutting processes present engineering challenges such as tool wear, poor machining quality, and frequent workpiece scrap. The latest high-strength gear steel, CH1900, boasts a yield strength exceeding 1700 MPa and a hardness exceeding 68 HRC. Furthermore, even after heat treatment and quenching, the surface hardness reaches 68 HRC, which can cause deformation on the connecting surface and present the same challenges during remachining. Existing processes for machining the inner bore of high-strength gears suffer from low machining accuracy, uneven residual stress distribution on the inner bore surface, and significant deviations in surface topography and grain. These issues are particularly prominent when machining holes with an inner diameter of less than 20 mm. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a method and system for efficiently and precisely machining the inner bore of a high-hardness and high-strength gear, which can reduce tool wear, improve machining efficiency and workpiece quality.

[0004] In a first aspect, an embodiment of the present invention provides a method for efficiently and precisely machining an inner hole of a high-hardness and high-strength gear. The method for efficiently and precisely machining an inner hole of a high-hardness and high-strength gear comprises:

[0005] Increasing the cutting area for machining the inner hole of the gear, and collecting the cutting force for machining the inner hole of the gear each time the cutting area is increased;

[0006] Calculate and obtain multiple displacement change values ​​by collecting all cutting forces for machining the inner hole of the gear;

[0007] Calculating and obtaining a plurality of actual cutting depths according to the plurality of displacement change values;

[0008] Calculating and obtaining a plurality of actual cutting force coefficients according to the plurality of actual cutting depths;

[0009] Calculating and obtaining a plurality of stable regions according to the plurality of actual cutting force coefficients;

[0010] Intersecting the plurality of stable regions to obtain a common stable region, and obtaining a region with a maximum product of cutting depth and cutting speed within the common stable region;

[0011] determining cutting parameters in the region where the product is the largest, and calculating the torsion angle according to the cutting parameters;

[0012] According to the torsion angle, the actual installed tool rake angle and the actual installed tool clearance angle are calculated and obtained for machining the gear inner hole.

[0013] Compared with the prior art, the first aspect of the present invention has the following beneficial effects:

[0014] This method increases the cutting area for machining the inner hole of a gear, and collects the cutting force for machining the inner hole of the gear each time the cutting area increases. Multiple displacement change values ​​are calculated based on all the collected cutting forces for machining the inner hole of the gear, and multiple actual cutting depths are calculated based on the multiple displacement change values. Multiple actual cutting force coefficients are calculated based on the multiple actual cutting depths. By considering the influence of the actual cutting force on the actual cutting depth and the actual cutting force coefficient, the accuracy of subsequent calculation of stable regions can be improved. Multiple stable regions are calculated based on the multiple actual cutting force coefficients, and the multiple stable regions are intersected to obtain a common stable region. Within the common stable region, a region with the maximum product of the cutting depth and the cutting speed is obtained, and cutting parameters are determined within the region with the maximum product. The torsion angle is calculated based on the cutting parameters, and the actual installed tool rake angle and the actual installed tool clearance angle are calculated based on the torsion angle for machining the inner hole of the gear. The actual installed tool rake angle and the actual installed tool clearance angle for machining the inner hole of the gear are calculated by considering the actual cutting force coefficient and the stable region. Installing the tool based on the actual installed tool rake angle and the actual installed tool clearance angle can reduce tool wear and improve machining efficiency and workpiece quality.

[0015] According to some embodiments of the present invention, the displacement change value is calculated as follows:

[0016]

[0017] Among them, l δ Indicates the displacement change value, F i-x represents the cutting force component of the i-th cutting force in the x direction, l represents the length of the tool, E represents the elastic modulus, I p represents the polar moment of inertia.

[0018] According to some embodiments of the present invention, the actual cutting depth is calculated as follows:

[0019] h f =h-δ h -l δ

[0020] Among them, h f represents the actual cutting depth, h represents the cutting depth, δ h Indicates the change in cutting depth, δ h =r(1-cosδ), δ represents the torsion angle, and r represents the radius of the gear inner hole.

[0021] According to some embodiments of the present invention, the actual cutting force coefficient is calculated as follows:

[0022]

[0023] Among them, φ i Represents the actual cutting force coefficient, F i represents the i-th cutting force, f z Indicates feed rate, h i represents the i-th cutting depth.

[0024] According to some embodiments of the present invention, calculating and obtaining a plurality of stable regions based on the plurality of actual cutting force coefficients includes:

[0025] Conduct modal testing to obtain the modal parameters of the tool tip;

[0026] A frequency domain method is used to calculate and obtain a plurality of stable regions according to the modal parameters of the tool tip and the plurality of actual cutting force coefficients.

[0027] According to some embodiments of the present invention, the twist angle is calculated as follows:

[0028]

[0029] Among them, δ s Indicates the twist angle, l indicates the length of the tool, I p represents the polar moment of inertia, T represents the torque, T=F i-x ρ, ρ represents the radius, F i-x represents the cutting force component of the i-th cutting force in the x direction, G represents the shear elastic modulus, μ represents Poisson's ratio, and E represents elastic modulus.

[0030] According to some embodiments of the present invention, the actual installed tool rake angle and the actual installed tool clearance angle for machining the inner hole of a gear are calculated as follows:

[0031] The actual installed tool rake angle for machining the inner hole of the gear is calculated as: Indicates the front angle under ideal working conditions;

[0032] The actual installation tool clearance angle for machining the inner hole of the gear is calculated as: Indicates the clearance angle under ideal working conditions.

[0033] In a second aspect, an embodiment of the present invention further provides a system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear. The system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear comprises:

[0034] A data acquisition unit, configured to increase the cutting area for machining the inner hole of the gear and to collect the cutting force for machining the inner hole of the gear each time the cutting area increases;

[0035] A first calculation unit is configured to calculate and obtain a plurality of displacement change values ​​by using all collected cutting forces for machining the inner hole of the gear;

[0036] A second calculation unit is used to calculate and obtain multiple actual cutting depths according to the multiple displacement change values;

[0037] a third calculating unit, configured to calculate and obtain a plurality of actual cutting force coefficients according to the plurality of actual cutting depths;

[0038] A first region acquisition unit is configured to calculate and obtain a plurality of stable regions according to the plurality of actual cutting force coefficients;

[0039] a second region acquisition unit, configured to obtain an intersection of the plurality of stable regions to obtain a common stable region, and to obtain a region with a maximum product of cutting depth and cutting speed within the common stable region;

[0040] a fourth calculation unit, configured to determine cutting parameters within the region where the product is maximum, and calculate a torsion angle according to the cutting parameters;

[0041] The fifth calculation unit is used to calculate the actual installation tool front angle and the actual installation tool back angle according to the torsion angle for machining the gear inner hole.

[0042] In the third aspect, an embodiment of the present invention also provides a device for efficiently and precisely processing the inner hole of a high-hardness and high-strength gear, comprising at least one control processor and a memory for communicating with the at least one control processor; the memory stores instructions that can be executed by the at least one control processor, and the instructions are executed by the at least one control processor so that the at least one control processor can execute the method as described above for efficiently and precisely processing the inner hole of a high-hardness and high-strength gear.

[0043] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the above-mentioned method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear.

[0044] It can be understood that the beneficial effects of the above-mentioned second to fourth aspects compared with the relevant technologies are the same as the beneficial effects of the above-mentioned first aspect compared with the relevant technologies. Please refer to the relevant description in the above-mentioned first aspect and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0046] Figure 1 This is a flow chart of a method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear according to one embodiment of the present invention;

[0047] Figure 2 is a schematic diagram of a gear inner hole machining device according to an embodiment of the present invention;

[0048] Figure 3 is a schematic diagram of a gear inner hole and a cutting cross section of a tool according to an embodiment of the present invention;

[0049] Figure 4 This is a structural diagram of a system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear according to an embodiment of the present invention. DETAILED DESCRIPTION

[0050] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0051] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0052] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientation or positional relationship indicated by up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0053] In the description of the present invention, it should be noted that, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0054] High-strength gears are widely used in aircraft engine transmission systems. To meet the requirements of high speeds, high load capacity, and high temperatures, high-strength gears require increasingly higher hardness and strength. These high-strength gears connect to the drive shaft through an inner bore. The dynamic high-frequency forces generated during gear meshing continuously impact the surface where the inner bore meets the shaft, placing higher demands on the shaft's shape, dimensional accuracy, microstructure, and contact properties. Traditional cutting processes present engineering challenges such as tool wear, poor machining quality, and frequent workpiece scrap. The latest high-strength gear steel, CH1900, boasts a yield strength exceeding 1700 MPa and a hardness exceeding 68 HRC. Furthermore, even after heat treatment and quenching, the surface hardness reaches 68 HRC, which can cause deformation on the connecting surface and present the same challenges during remachining. Existing processes for machining the inner bore of high-strength gears suffer from low machining accuracy, uneven residual stress distribution on the inner bore surface, and significant deviations in surface topography and grain. These issues are particularly prominent when machining holes with an inner diameter of less than 20 mm.

[0055] To solve the above problems, the present invention increases the cutting area of ​​the gear inner hole and collects the cutting force of the gear inner hole each time the cutting area increases. Based on all the collected cutting forces for the gear inner hole, multiple displacement change values ​​are calculated. Based on the multiple displacement change values, multiple actual cutting depths are calculated. Based on the multiple actual cutting depths, multiple actual cutting force coefficients are calculated. By considering the influence of the actual cutting force on the actual cutting depth and the actual cutting force coefficient, the accuracy of the subsequent calculation of the stable region can be improved. Based on the multiple actual cutting force coefficients, multiple stable regions are calculated, and the multiple stable regions are intersected to obtain a common stable region. Within the common stable region, a region with the maximum product of the cutting depth and the cutting speed is obtained. Cutting parameters are determined within the region with the maximum product. The torsion angle is calculated based on the cutting parameters. Based on the torsion angle, the actual installed tool rake angle and the actual installed tool clearance angle are calculated for machining the gear inner hole. The actual installed tool rake angle and the actual installed tool clearance angle for machining the gear inner hole are calculated by considering the actual cutting force coefficient and the stable region. Installing the tool based on the actual installed tool rake angle and the actual installed tool clearance angle can reduce tool wear and improve machining efficiency and workpiece quality.

[0056] Reference Figure 1 The embodiment of the present invention provides a method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear. The method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear includes but is not limited to steps S100 to S800, wherein:

[0057] Step S100: increasing the cutting area of ​​the gear inner hole and collecting the cutting force of the gear inner hole each time the cutting area increases;

[0058] Step S200: Calculate and obtain multiple displacement change values ​​by collecting the cutting forces of all gear inner holes;

[0059] Step S300: Calculate and obtain multiple actual cutting depths based on multiple displacement change values;

[0060] Step S400: Calculate and obtain multiple actual cutting force coefficients based on multiple actual cutting depths;

[0061] Step S500: Calculate and obtain multiple stable regions based on multiple actual cutting force coefficients;

[0062] Step S600: finding the intersection of multiple stable regions to obtain a common stable region, and obtaining a region with the maximum product of cutting depth and cutting speed within the common stable region;

[0063] Step S700: determining cutting parameters in the area where the product is the largest, and calculating the torsion angle according to the cutting parameters;

[0064] Step S800: Calculate the actual installed tool rake angle and the actual installed tool clearance angle according to the torsion angle for machining the gear inner hole.

[0065] In steps S100 to S800 of some embodiments, in order to consider the influence of the actual cutting force on the actual cutting depth and the actual cutting force coefficient, so as to improve the accuracy of the subsequent calculation of the stable area, the present embodiment increases the cutting area of ​​the gear inner hole, and collects the cutting force of the gear inner hole each time the cutting area increases, and calculates multiple displacement change values ​​through all the collected cutting forces of the gear inner hole, and calculates multiple actual cutting depths based on the multiple displacement change values, and calculates multiple actual cutting force coefficients based on the multiple actual cutting depths; in order to reduce tool wear, improve processing efficiency and workpiece quality, the present embodiment calculates multiple stable areas based on the multiple actual cutting force coefficients, intersects the multiple stable areas to obtain a common stable area, and obtains the area with the largest product of the cutting depth and the cutting speed in the common stable area, determines the cutting parameters in the area with the largest product, calculates the torsion angle based on the cutting parameters, and calculates the actual installed tool front angle and the actual installed tool back angle for processing the gear inner hole based on the torsion angle.

[0066] In some embodiments, the displacement change value is calculated as follows:

[0067]

[0068] Among them, l δ Indicates the displacement change value, F i-x represents the cutting force component of the i-th cutting force in the x direction, l represents the length of the tool, E represents the elastic modulus, I prepresents the polar moment of inertia.

[0069] In this embodiment, the displacement change caused by the bending moment caused by the cutting force component in the x-direction of the cutting force is taken into account to improve the accuracy of the subsequent calculation of the actual cutting depth and the actual cutting force coefficient.

[0070] In some embodiments, the actual depth of cut is calculated as follows:

[0071] h f =h-δ h -l δ

[0072] Among them, h f Indicates the actual cutting depth, h indicates the cutting depth, δ h Indicates the change in cutting depth, δ h =r(1-cosδ), δ represents the torsion angle, and r represents the radius of the gear inner hole.

[0073] In some embodiments, the actual cutting force coefficient is calculated as follows:

[0074]

[0075] Among them, φ i Indicates the actual cutting force coefficient, F i represents the i-th cutting force, f z Indicates feed rate, h i represents the i-th cutting depth.

[0076] In some embodiments, multiple stable regions are calculated based on multiple actual cutting force coefficients, including:

[0077] Conduct modal testing to obtain the modal parameters of the tool tip;

[0078] According to the modal parameters of the tool tip and multiple actual cutting force coefficients, multiple stable regions are obtained by frequency domain method.

[0079] In this embodiment, the accuracy of calculating the stable region is improved by taking the actual cutting force coefficient into consideration.

[0080] In some embodiments, the twist angle is calculated as follows:

[0081]

[0082] Among them, δ s Indicates the twist angle, l indicates the length of the tool, I p represents the polar moment of inertia, T represents the torque, T=F i-x ρ, ρ represents the radius, F i-xrepresents the cutting force component of the i-th cutting force in the x direction, G represents the shear elastic modulus, μ represents Poisson's ratio, and E represents elastic modulus.

[0083] In some embodiments, the actual installed tool rake angle and the actual installed tool clearance angle for machining the inner hole of the gear are calculated as follows:

[0084] The actual installed tool rake angle for machining the inner hole of the gear is calculated as: Indicates the front angle under ideal working conditions;

[0085] The actual installation tool clearance angle for machining the inner hole of the gear is calculated as: Indicates the clearance angle under ideal working conditions.

[0086] In this embodiment, the tool is installed by installing the tool based on the calculated actual tool rake angle and actual tool clearance angle, which can reduce tool wear and improve machining efficiency and workpiece quality.

[0087] To facilitate understanding by those skilled in the art, a set of best embodiments is provided below:

[0088] The inner hole of the gear to be machined and its machining allowance are fixed on the lathe through the clamping device on the lathe, and the workpiece is driven to rotate. The gear inner hole machining device for precision machining of high-strength and high-hardness gear inner holes is fixed to the indexable worktable of the lathe through bolts or pressure plates, and the device is driven to move along the feed direction by the movement of the lathe worktable. Figure 2 , Figure 2 The diagram of the gear inner hole machining device is shown in Figure 1, where 1 is the gear to be machined, 2 is the gear inner hole allowance to be machined, 3 is a tool with a specific structure, 4 is the tool tip target point, and 5 is the tool bar observation point. Figure 3 , Figure 3 The figure below is a schematic diagram of the gear inner hole and the tool cutting section, where 6 is the gear cross-section machining allowance and 7 is the tool. The shaft length of existing gears is generally no more than 300 mm, so the maximum displacement of the processing device in the feed direction does not exceed 100 mm to meet the requirements. A tool length of 100 mm can meet the machining requirements of most gear inner holes, that is, the tool length in the z direction does not exceed 100 mm. The feed rate is set to f z , the cutting depth is set to h, the cutting speed is set to v, the gear inner hole radius is set to r, and the rotational speed is set to N, then the cutting speed v is: v = 2πNr.

[0089] The control implementation process is as follows:

[0090] (1) Conduct a cutting force coefficient identification test. Use a workpiece with the same material as the inner hole of a high-strength and high-hardness gear, and a tool that is consistent with the tool used for cutting high-strength and high-hardness gears. The ultrasonic vibration device is turned on with a power of 50% of the maximum ultrasonic vibration power.

[0091] (2) A data acquisition system consisting of a displacement sensor, an LMS data acquisition system, and a charge amplifier is used to collect data under no-load conditions when the ultrasonic vibration device is turned on at 50% of its rated power. Since the vibration amplitude of the tool tip target point cannot be measured during the cutting process, it can only be measured under the application of cutting force load. The amplitudes of the tool tip target point and the tool bar observation point are collected, where the tool bar observation point is a non-vibration node. The vibration amplitude changes with time, and pressure is continuously applied to obtain loads k1, k2, ..., k i ,…,k n , the vibration amplitudes of the tool tip target point are α1, α2, …, α i ,…,α n , the vibration amplitudes of the tool bar observation points are β1, β2, ..., β i ,…,β n , then the ratios between the vibration amplitudes of the tool tip target point and the tool bar observation point are: γ1, γ2, …, γ i ,…,γ n , then we get Considering that the amplitude of the ultrasonic vibration device will gradually decrease as the load increases, the cutting force load and the ratio The least squares function is used to fit the cutting force load and the ratio, and the functional relationship between them is γ = f(k i ).

[0092] (3) Cutting area s is the ratio of cutting depth h and feed rate f z The product of s = hf z Starting from the initial cutting area μ, it increases in increments Δ and stops increasing when it reaches the end value ω. In order to be closer to actual engineering problems, the initial value is determined by the minimum value in the commonly used processing parameters or process regulations, and the end value is determined by the maximum value in the commonly used processing parameters or process regulations. For example, the cutting area starts from the initial value of 0.5mm 2 Start by cutting in increments of 0.5 mm. 2 Increase gradually to the end value of 4mm 2 The cutting increments are s1, s2, ..., s i ,…,s n When the cutting forces collected by the dynamometer are F1, F2, ..., F i ,…,F n , the cutting force components in the x direction are F 1-x , F 2-x ,…,Fi-x ,…,F n-x , the cutting force components in the y direction are F 1-y , F 2-y ,…,F i-y ,…,F n-y , the z-direction cutting force components are F 1-z , F 2-z ,…,F i-z ,…,F n-z The vibration amplitudes of the tool bar observation points are η1, η2, ..., η i ,…,η n , then the cutting force coefficients are φ1, φ2, …, φ i ,…,φ n , the vibration amplitudes of the tool tip target point are χ1, χ2, ..., χ i ,…,χ n , and obtain χ i =γ i η i , γ i =f(F i This indicates that the vibration amplitude at the tool tip target point is the ultrasonic vibration amplitude under the actual cutting force load. The cutting force coefficient is the cutting force coefficient under the ultrasonic vibration amplitude under the actual cutting force load, and the tool angle is also the tool angle under the actual ultrasonic vibration amplitude.

[0093] (4) Let the length of the tool shank be l, the radius be ρ, and r s The shape is circular, and the shear elastic modulus is: Where E is the elastic modulus and μ is the Poisson's ratio, which is a known material parameter.

[0094] Then the polar moment of inertia is: I p =∫ A ρ 2 dA; the torsion angle δ is: Where T is the torque, T = F i-x ρ, F i-x is the cutting force component of the i-th cutting force in the x-direction. The angular offset caused by the torsion angle is the torsion angle δ, and the effective rake angle of the tool in actual cutting is: ζ s =ζ1-δ, the effective back angle is: Where ζ1 is the geometric rake angle of the tool, is the geometric relief angle of the tool. The change in cutting depth caused by h =r(1-cosδ).

[0095] The displacement change l caused by the bending moment caused by the x-direction component of the i-th cutting force δ for:

[0096] After considering the influence of the x and y direction components of the cutting force on the cutting depth, the actual cutting depth is: h f =h-δ h -l δ The actual cutting force coefficients are φ1, φ2, ..., φ i ,…,φ n ,in:

[0097]

[0098] (5) Carry out modal testing to obtain the modal parameters of the tool tip, and solve the stable region according to the frequency domain method. The cutting force coefficients are obtained in sequence as φ1, φ2, ..., φ i ,…,φ n When the stable regions are ψ1, ψ2, …, ψ i ,…,ψ n . By finding the intersection of the above stable areas, we can obtain the effective stable area (i.e., the common stable area) when the ultrasonic vibration amplitude is 50% of the rated power of the ultrasonic vibration device. Based on the effective stable area, the area where the product of the cutting depth h and the cutting speed v is the largest is selected to improve the material removal efficiency. Because if the area where the product of the cutting speed and the cutting depth is the largest is not obtained by this method, it cannot be ensured that it is within the effective stable area, that is, the obtained cutting speed and cutting depth may be outside the common stable area, and the tool will vibrate. After the vibration, the tool will vibrate abnormally, the surface integrity will be destroyed, the edge will break, and the workpiece will be easily scrapped.

[0099] (6) When cutting and installing the tool, the cutting parameters determined in (5) are used to consider the influence of the cutting force on the tool rake angle and tool back angle. According to the model in (4), the influence of the cutting force on the angle is considered and the torsion angle is obtained as δ s , specifically:

[0100]

[0101] Establish the installation angle model of the tool rake angle and back angle: If the rake angle under ideal working conditions and the back angle under ideal working conditions are The actual installed tool front angle and the actual installed tool back angle are: pass and Adjusting the rake and clearance angles of the tool to machine the inner hole of a gear can reduce tool wear, improve machining efficiency, and increase workpiece quality. Because the tool angles in actual machining will deviate from the ideal rake and clearance angles, to compensate for the effects of torsion, the torsion angle is pre-compensated during tool setting.

[0102] In this embodiment, the existing cutting force coefficient and cutting depth do not take into account the actual situation, while this embodiment takes into account the impact of the actual cutting force on the dynamic cutting depth, and the cutting force coefficient takes into account the impact of the ultrasonic vibration amplitude under the actual cutting force load. If these factors are not taken into account, the actual cutting amount deviates from the set processing parameters (such as the front angle and back angle of the tool cutting angle, etc.). After deviating from the set angle (the tool setting processing angle is the tool's optimal processing angle), the tool cutting angle is too large, and tool wear is aggravated. This embodiment calculates the stable area through the actual cutting force coefficient, making the calculation results of the stable area more effective, and the determined efficient cutting parameters are also more reliable, avoiding abnormal vibration of the cutting tool and scrapping of the workpiece.

[0103] Reference Figure 4 The embodiment of the present invention further provides a system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear. The system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear comprises a data acquisition unit 100, a first calculation unit 200, a second calculation unit 300, a third calculation unit 400, a first area acquisition unit 500, a second area acquisition unit 600, a fourth calculation unit 700, and a fifth calculation unit 800, wherein:

[0104] The data acquisition unit 100 is used to increase the cutting area of ​​the gear inner hole and collect the cutting force of the gear inner hole each time the cutting area increases;

[0105] The first calculation unit 200 is used to calculate and obtain multiple displacement change values ​​by collecting the cutting forces of all the gear inner holes being processed;

[0106] The second calculation unit 300 is used to calculate and obtain multiple actual cutting depths according to the multiple displacement change values;

[0107] The third calculation unit 400 is used to calculate and obtain multiple actual cutting force coefficients according to multiple actual cutting depths;

[0108] A first region acquisition unit 500 is configured to calculate and obtain a plurality of stable regions according to a plurality of actual cutting force coefficients;

[0109] The second region acquisition unit 600 is configured to obtain an intersection of the plurality of stable regions to obtain a common stable region, and to obtain a region within the common stable region where the product of the cutting depth and the cutting speed is the largest;

[0110] A fourth calculation unit 700 is configured to determine cutting parameters within the region where the product is the largest, and calculate a torsion angle based on the cutting parameters;

[0111] The fifth calculation unit 800 is used to calculate the actual installed tool front angle and the actual installed tool back angle according to the torsion angle for machining the gear inner hole.

[0112] It should be noted that since the system for efficiently and precisely processing the inner hole of a high-hardness and high-strength gear in this embodiment and the method for efficiently and precisely processing the inner hole of a high-hardness and high-strength gear mentioned above are based on the same inventive concept, the corresponding contents in the method embodiment are also applicable to the system embodiment and will not be described in detail here.

[0113] An embodiment of the present invention further provides a device for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear, comprising: at least one control processor and a memory for communicating with the at least one control processor.

[0114] The memory, as a non-transient computer-readable storage medium, can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0115] The non-transient software program and instructions required to implement the method of efficiently and precisely machining the inner hole of a high-hardness and high-strength gear in the above embodiment are stored in the memory. When executed by the processor, the method of efficiently and precisely machining the inner hole of a high-hardness and high-strength gear in the above embodiment is executed, for example, the method described above is executed. Figure 1 Method steps S100 to S800.

[0116] The system embodiment described above is merely illustrative. The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Some or all of these units may be selected based on actual needs to achieve the objectives of this embodiment.

[0117] The embodiment of the present invention further provides a computer-readable storage medium storing computer-executable instructions, which are executed by one or more control processors to enable the one or more control processors to execute a method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear in the above method embodiment, for example, to execute the above-described Figure 1 The functions of method steps S100 to S800 in the embodiment of the present invention are as follows:

[0118] Those skilled in the art will appreciate that all or some of the steps and systems in the method disclosed above can be implemented as software, firmware, hardware, and appropriate combinations thereof. Some physical components or all physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, and the computer-readable medium can include computer storage media (or non-transitory media) and communication media (or temporary media). As known to those skilled in the art, the term computer storage media is included in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data) and is volatile and non-volatile, removable, and non-removable. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory, or other memory technology, CD-ROM, digital versatile disks (DVD), or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage, or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, as is well known to those skilled in the art, communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0119] The above is a specific description of the preferred implementation of the embodiments of the present application, but the embodiments of the present application are not limited to the above-mentioned implementation methods. Technical personnel familiar with the art can also make various equivalent modifications or substitutions without violating the spirit of the embodiments of the present application. These equivalent modifications or substitutions are all included in the scope defined by the claims of the embodiments of the present application.

Claims

1. A method for high-efficiency and precision machining of the inner hole of a high-hardness and high-strength gear, characterized in that: The method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear comprises: Increasing the cutting area for machining the inner hole of the gear, and collecting the cutting force for machining the inner hole of the gear each time the cutting area is increased; By collecting all the cutting forces for machining the inner hole of the gear, a plurality of displacement change values ​​are calculated, wherein the displacement change values ​​are calculated in the following manner: Among them, l δ Indicates the displacement change value, F i-x represents the cutting force component of the i-th cutting force in the x direction, l represents the length of the tool, E represents the elastic modulus, I p represents the polar moment of inertia; A plurality of actual cutting depths are calculated based on the plurality of displacement change values, wherein the actual cutting depths are calculated in the following manner: h f =h-δ h -l δ Among them, h f represents the actual cutting depth, h represents the cutting depth, δ h Indicates the change in cutting depth, δ h =r(1-cosδ), δ represents the torsion angle, r represents the radius of the gear inner hole; According to the multiple actual cutting depths, multiple actual cutting force coefficients are calculated, wherein the actual cutting force coefficients are calculated in the following manner: Among them, φ i Represents the actual cutting force coefficient, F i represents the i-th cutting force, f z Indicates feed rate, h i represents the i-th cutting depth; Calculating and obtaining a plurality of stable regions according to the plurality of actual cutting force coefficients; Intersecting the plurality of stable regions to obtain a common stable region, and obtaining a region with a maximum product of cutting depth and cutting speed within the common stable region; determining cutting parameters in the region where the product is the largest, and calculating the torsion angle according to the cutting parameters; According to the torsion angle, the actual installed tool rake angle and the actual installed tool clearance angle are calculated and obtained for machining the gear inner hole.

2. The method for high-efficiency and precision machining of the inner hole of a high-hardness and high-strength gear according to claim 1 is characterized in that: The step of calculating and obtaining a plurality of stable regions based on the plurality of actual cutting force coefficients includes: Conduct modal testing to obtain the modal parameters of the tool tip; A frequency domain method is used to calculate and obtain a plurality of stable regions according to the modal parameters of the tool tip and the plurality of actual cutting force coefficients.

3. The method for high-efficiency and precision machining of the inner hole of a high-hardness and high-strength gear according to claim 1, characterized in that: The twist angle is calculated as follows: Among them, δ s Indicates the twist angle, l indicates the length of the tool, I p represents the polar moment of inertia, T represents the torque, T=F i-x ρ, ρ represents the radius, F i-x represents the cutting force component of the i-th cutting force in the x direction, G represents the shear elastic modulus, μ represents Poisson's ratio, and E represents elastic modulus.

4. The method for high-efficiency and precision machining of the inner hole of a high-hardness and high-strength gear according to claim 3, characterized in that: The actual installed tool rake angle and actual installed tool clearance angle for machining the gear inner hole are calculated as follows: The actual installed tool rake angle for machining the inner hole of the gear is calculated as: Indicates the rake angle under ideal working conditions; The actual installation tool clearance angle for machining the inner hole of the gear is calculated as: Indicates the clearance angle under ideal working conditions.

5. A system for high-efficiency and precision machining of high-hardness and high-strength gear inner holes, characterized in that: The system for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear comprises: A data acquisition unit, configured to increase the cutting area for machining the inner hole of the gear and to collect the cutting force for machining the inner hole of the gear each time the cutting area increases; The first calculation unit is configured to calculate a plurality of displacement change values ​​by using all collected cutting forces for machining the inner hole of the gear, wherein the displacement change values ​​are calculated in the following manner: Among them, l δ Indicates the displacement change value, F i-x represents the cutting force component of the i-th cutting force in the x direction, l represents the length of the tool, E represents the elastic modulus, I p represents the polar moment of inertia; The second calculation unit is configured to calculate a plurality of actual cutting depths according to the plurality of displacement change values, wherein the actual cutting depths are calculated in the following manner: h f =h-δ h -l δ Among them, h f represents the actual cutting depth, h represents the cutting depth, δ h Indicates the change in cutting depth, δ h =r(1-cosδ), δ represents the torsion angle, r represents the radius of the gear inner hole; A third calculation unit is configured to calculate a plurality of actual cutting force coefficients based on the plurality of actual cutting depths, wherein the actual cutting force coefficients are calculated in the following manner: Among them, φ i Represents the actual cutting force coefficient, F i represents the i-th cutting force, f z Indicates feed rate, h i represents the i-th cutting depth; A first region acquisition unit is configured to calculate and obtain a plurality of stable regions according to the plurality of actual cutting force coefficients; a second region acquisition unit, configured to obtain an intersection of the plurality of stable regions to obtain a common stable region, and to obtain a region with a maximum product of cutting depth and cutting speed within the common stable region; a fourth calculation unit, configured to determine cutting parameters within the region where the product is maximum, and calculate a torsion angle according to the cutting parameters; The fifth calculation unit is used to calculate the actual installation tool front angle and the actual installation tool back angle according to the torsion angle for machining the gear inner hole.

6. A device for high-efficiency and precision machining of the inner hole of high-hardness and high-strength gears, characterized in that: It includes at least one control processor and a memory for communicating with the at least one control processor; the memory stores instructions that can be executed by the at least one control processor, and the instructions are executed by the at least one control processor to enable the at least one control processor to execute the method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the method for efficiently and precisely machining the inner hole of a high-hardness and high-strength gear as described in any one of claims 1 to 4.

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