Dynamic grinding force simulation calculation method and system based on generating grinding worm

Abstract

The present invention relates to a dynamic grinding force simulation calculation method and system based on a generated gear-grinding worm. The simulation calculation method first obtains the homogeneous coordinate matrix of the worm grinding wheel. Then, a coordinate conversion function reflecting the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system is constructed, and the homogeneous coordinates of the grinding wheel are transformed into the workpiece coordinate system. Then, a scattered point cloud of the tooth groove to be ground is established according to the processing information and the involute equation. According to the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground, simulated processing is performed to obtain an undeformed chip point cloud during the processing. Finally, the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground is calculated, and then the cross-sectional area of the undeformed chip is obtained after the distance is integrated, and then the grinding force of any processing point is calculated. This method effectively reduces the difficulty of estimating the grinding force during the worm grinding wheel tooth grinding process, and can efficiently complete the simulation processing task.

Description

Technical Field

[0001] The present invention relates to the technical field of gear finishing, and in particular to a dynamic grinding force simulation calculation method based on a generating grinding worm, as well as a computer terminal, a readable storage medium and a simulation calculation system applying the method. Background Art

[0002] Gears are essential components of modern engineering machinery. Most gears are machined using the generating method. Gear grinding, the final step in gear finishing, directly impacts gear accuracy and transmission performance. Because generating grinding involves continuous grinding, the contact point between the worm and the workpiece constantly changes. This dynamic generation of grinding forces can cause machine tool vibration, resulting in gear machining errors and a direct impact on gear accuracy. Therefore, research on grinding force prediction is highly helpful in improving gear grinding accuracy and extending gear life.

[0003] At present, most of the research on grinding force prediction adopts the method of solid modeling and simulation processing. Since this method has high requirements on the configuration of the simulation platform and a large workload, it sometimes takes several days to complete the simulation task. The efficiency is too low and it is difficult to meet the needs of efficiently completing simulation processing tasks. Summary of the Invention

[0004] Based on this, it is necessary to address the technical problem in the existing technology that the grinding force prediction efficiency of the worm grinding wheel during the gear grinding process is low and the simulation processing tasks cannot be completed efficiently. The present invention provides a dynamic grinding force simulation calculation method and system based on the generated gear grinding worm.

[0005] The present invention discloses a dynamic grinding force simulation calculation method based on a generating grinding worm, and the simulation calculation method comprises the following steps:

[0006] S1. Obtain the homogeneous coordinate matrix of the worm grinding wheel.

[0007] S2. Construct a coordinate conversion function that reflects the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, and then transform the grinding wheel homogeneous coordinates into the workpiece coordinate system.

[0008] S3. Create a scattered point cloud of the tooth groove to be ground based on the processing information and the involute equation.

[0009] S4. Perform simulated processing based on the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground to obtain an undeformed chip point cloud during the processing. The method for obtaining the undeformed chip point cloud includes the following steps:

[0010] S41. Obtain a cylindrical region of the outer edge shape of the gear to be ground.

[0011] S42. The data points of the worm grinding wheel located in the cylindrical area among all the data points of the workpiece coordinate system are used as the grinding points of the worm grinding wheel.

[0012] S43. Fit the homogeneous coordinates of the scattered point cloud of the tooth groove to be ground, and then envelop to form a three-dimensional solid area.

[0013] S44. All worm grinding wheel grinding points outside the three-dimensional solid area are used as data points of undeformed chips to form an undeformed chip point cloud.

[0014] S5. Calculate the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground, integrate the distance to obtain the cross-sectional area of the undeformed chip, and then calculate the grinding force at any processing point.

[0015] As a further improvement of the above solution, in S1, the method for obtaining the homogeneous coordinate matrix of the worm grinding wheel includes the following process:

[0016] Set the three-dimensional homogeneous coordinates of the axial tooth profile of the worm grinding wheel and a spiral matrix used to describe the spiral transformation motion.

[0017] The three-dimensional homogeneous coordinates of the axial tooth profile are multiplied by the spiral matrix to obtain the secondary coordinate matrix of the worm grinding wheel.

[0018] As a further improvement of the above solution, in S2, the expression of the coordinate conversion function is:

[0019] M(t,ω,φ)=RT x (φ) RT y (δ)·RT z (ψ)·W(t,ω)

[0020] Where W(t,ω) represents the homogeneous coordinates of any point on the worm grinding wheel model, and M(t,ω,φ) represents the homogeneous coordinates of the point mapped to the workpiece coordinate system. y (δ) represents the transformation matrix from the grinding wheel coordinate system to a tool coordinate system. RT x (φ) represents the transformation matrix from the tool setting coordinate system to the machine tool reference coordinate system. RT z (φ) represents the coordinate matrix from the machine tool's reference coordinate system to the workpiece coordinate system.

[0021] As a further improvement of the above scheme, in S3, the homogeneous coordinates of the scattered points on the ideal tooth surface are obtained through an involute equation, and then the predetermined grinding allowance is added to the normal direction of all the scattered points on the ideal tooth surface, and finally the scattered point cloud of the tooth groove to be ground is obtained.

[0022] As a further improvement of the above solution, in S5, the grinding force F at any processing pointc The expression formula is:

[0023]

[0024] Where μ represents the inherent parameter related to the grinding ability and material removal efficiency of the grinding wheel. s A represents the effective grinding wheel width. k is the grinding force per unit area. n is the friction factor during the grinding process. cu is the area of the overlapping surface. l is the arbitrary contact length of the contact arc in cylindrical grinding, and s is the integral upper limit of l. d (l) is the number of dynamic grinding edges within the range of any contact length l of the external cylindrical grinding contact arc.

[0025] As a further improvement of the above scheme, the number of dynamic grinding edges N within the range of any contact arc length l of the external cylindrical grinding contact arc is d The expression formula of (l) is:

[0026]

[0027] Where A n is the proportional coefficient. C e is the abrasive density. w and V s are the linear speed of the grinding wheel and the workpiece removal speed respectively. p is the cutting depth. e is the equivalent grinding wheel diameter. s is the contact length. α and β are indices that characterize the distribution of abrasive particles on the working surface of the grinding wheel.

[0028] As a further improvement of the above scheme, for cylindrical grinding, the equivalent grinding wheel diameter d e The calculation formula is:

[0029]

[0030] Where, d w is the diameter of a simulated workpiece with a circular surface, and the simulated workpiece is used to simulate the geometry of any point on the involute tooth surface of the workpiece to be machined. s The diameter of a simulated grinding wheel with a circular surface, which is used to simulate the surface of a worm grinding wheel.

[0031] The present invention also discloses a computer terminal, which includes a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the program, it implements any one of the steps of the above-mentioned dynamic grinding force simulation calculation method based on the generated grinding worm.

[0032] The present invention also discloses a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the program implements any one of the steps of the above-mentioned dynamic grinding force simulation calculation method based on the generating grinding worm.

[0033] The present invention also discloses a dynamic grinding force simulation calculation system based on a generating gear grinding worm, which applies any of the above-mentioned dynamic grinding force simulation calculation methods based on a generating gear grinding worm. The dynamic grinding force simulation calculation system includes: a data acquisition module and a calculation module.

[0034] The data acquisition module is used to first obtain the homogeneous coordinate matrix of the worm grinding wheel, and construct a coordinate conversion function that reflects the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, and then transform the homogeneous coordinates of the grinding wheel into the workpiece coordinate system. Then, according to the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground, simulated processing is performed to obtain the undeformed chip point cloud during the processing process.

[0035] The calculation module is used to calculate the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground, and then integrate the distance to obtain the cross-sectional area of the undeformed chip, and then calculate the grinding force of any processing point.

[0036] Compared with the prior art, the technical solution disclosed in the present invention has the following beneficial effects:

[0037] 1. This grinding force simulation calculation method is based on the spatial forming mechanism of the tooth surface of continuous gear grinding. First, a parametric worm grinding wheel model and discrete tooth surfaces to be processed are established according to the parameters of the grinding wheel and workpiece. Then, the gear grinding working surface is simulated through the principle of gear grinding motion. Subsequently, chip data points are selected for the discrete working surface. Finally, the grinding force is calculated through the chip cross-sectional area, and the influence of different axial feed rates on the grinding force is explored. The advantage of the present invention is that the simulation calculation is completed efficiently. The simulation task that the currently popular entity method requires several days to complete during the simulation process can be completed in just a few hours using this method, which greatly improves the efficiency of the simulation task. The authenticity of the simulation results is verified by the experimental method of collecting the gear grinding current wave, which can perfectly solve the problem of grinding force prediction. At the same time, this prediction model provides certain help for optimizing gear grinding process parameters, improving efficiency, and avoiding burns.

[0038] This simulation method can simulate the worm grinding process and calculate the grinding force, effectively reducing the difficulty of estimating the grinding force during worm grinding, thereby improving the efficiency of simulation tasks. It can also analyze the relationship between the grinding force and the worm's rotation angle during worm grinding, providing a theoretical basis for optimizing the structure and process parameters of worm grinding machines.

[0039] 2. This grinding force simulation calculation method establishes multiple mathematical models. For example, both the grinding wheel model and the surface model to be machined have homogeneous coordinates. This makes it easier to use the geometric conditions of undeformed chips. Furthermore, because homogeneous coordinate transformations are fully utilized, the inherent characteristics of each model are mathematical equations and coordinate data. Unlike solid simulation methods, which require 3D cutting, simulation results can be obtained more quickly, making it highly convenient.

[0040] 3. The grinding force simulation calculation method also calculates the number of abrasive grains involved in cutting by calculating the number of dynamic grinding edges, and also links the normal force with the effective grinding wheel width, making the grinding force calculation model more applicable in different grinding processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Flowchart of the dynamic grinding force simulation calculation based on the generating grinding worm in Example 1 of the present invention;

[0042] Figure 2 Schematic diagram of the axial tooth profile of the worm grinding wheel in Example 1 of the present invention;

[0043] Figure 3 This is a schematic diagram of the worm grinding wheel forming in Example 1 of the present invention;

[0044] Figure 4 Schematic diagram of coordinate transformation of continuous generating motion of worm grinding wheel in embodiment 1 of the present invention;

[0045] Figure 5 A schematic diagram of the tooth groove to be ground in Example 1 of the present invention is established;

[0046] Figure 6 Schematic diagram of the envelope of the tooth groove to be ground in Example 1 of the present invention;

[0047] Figure 7 This is a diagram showing the chip shape and chip cross-sectional area during gear grinding in Example 1 of the present invention;

[0048] Figure 8 Schematic diagram of grinding force decomposition in Example 1 of the present invention;

[0049] Figure 9 This is a grinding force prediction waveform diagram in Example 1 of the present invention;

[0050] Figure 10 This is a current fluctuation diagram obtained from the gear grinding machine processing experiment in Example 1 of the present invention;

[0051] Figure 11 This is a relationship diagram showing the influence of the axial feed rate on the grinding process in Example 1 of the present invention. DETAILED DESCRIPTION

[0052] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0053] It should be noted that when a component is referred to as being "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component. When a component is considered to be "fixed to" another component, it may be directly fixed to the other component or there may be a central component.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0055] Example 1

[0056] This embodiment provides a dynamic grinding force simulation calculation method based on a generating gear grinding worm, which can be used to simulate continuous generating gear grinding processing, ultimately obtaining undeformed cutting and then predicting the grinding force waveform.

[0057] Because each tooth groove in a gear machined using the generating method undergoes the same envelope process, the formation of a single workpiece tooth groove can be simulated. By enveloping the entire grinding wheel force within a single workpiece tooth groove, the overall grinding wheel force can be calculated. Furthermore, the grinding force gradually increases during the cut-in phase, reaches a maximum during the full-cut phase, and maintains a relatively constant periodic fluctuation, before gradually decreasing to zero during the cut-out phase. Because the grinding force is greatest during the full-cut phase and its fluctuation pattern is most pronounced, the grinding force simulation calculation method in this embodiment predicts the full-cut phase.

[0058] See also Figure 1 The simulation calculation method includes steps S1 to S5.

[0059] S1. Obtaining the homogeneous coordinate matrix of the worm grinding wheel. In this embodiment, the mathematical expression of the axial tooth profile of the worm grinding wheel can be calculated in sections, and then the homogeneous coordinates W(t,ω) of the worm grinding wheel are obtained by matrix transformation and spiral translation.

[0060] See also Figure 2In this embodiment, the right side of the axial tooth profile of the worm grinding wheel is divided into four parts for the convenience of calculation. The homogeneous coordinate Y(x) of the axial tooth profile of the worm grinding wheel is obtained according to the knowledge of the geometric characteristics of the worm grinding wheel and the involute equation, where the equation f(x) is the inverse involute equation interpolated from the involute scattered points.

[0061]

[0062] Where x a 、x b 、x c 、x d Respectively Figure 2 The distance between each segment point of the axial tooth profile and the origin (0, 0); r f Indicates tooth root height; D d Indicates the outer diameter of the grinding wheel; r c Indicates the fillet radius; S indicates the distance that the involute equation needs to be translated.

[0063] See also Figure 3 The worm grinding wheel is formed by the axial tooth profile spiraling around the axis. The three-dimensional homogeneous coordinates YT(t) of the axial tooth profile are set. Then, the transformation motion is described by the spiral matrix TR(ω). Then, YT(t) and TR(ω) are intersected to obtain the worm grinding wheel homogeneous coordinate matrix W(t,ω). The specific expression equation is as follows:

[0064]

[0065]

[0066] W(t,ω)=TR(ω)·YT(t)

[0067] Where ω represents the axial tooth profile rotation angle, r d represents the grinding wheel pitch circle radius, γ represents the grinding wheel helix angle, r d *ω*Tanγ represents the axial tooth profile translation distance, and t represents the x-axis coordinate in the axial truncation.

[0068] S2. Construct a coordinate conversion function that reflects the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, and then transform the grinding wheel homogeneous coordinates into the workpiece coordinate system. In this embodiment, according to the principle of continuous gear generation, multiple coordinate transformations are required to move from the grinding wheel coordinate system to the workpiece coordinate system. By using the matrix transformation characteristics, multiple coordinate change matrices are obtained, and the mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system is obtained:

[0069] M(t,ω,φ)=RT x (φ) RT y (δ)·RT z (ψ)·W(t,ω)

[0070] Where W(t,ω) represents the homogeneous coordinates of any point on the worm wheel model, and M(t,ω,φ) represents the homogeneous coordinates of the point mapped to the workpiece coordinate system. y (δ) represents the transformation matrix from the grinding wheel coordinate system to a tool coordinate system. RT x (φ) represents the transformation matrix from the tool setting coordinate system to the machine tool reference coordinate system. RT z (φ) represents the coordinate matrix from the machine tool's reference coordinate system to the workpiece coordinate system.

[0071] See also Figure 4 According to the structure of the gear grinding machine and the principle of gear grinding, the O0X0Y0Z0-O0X′0Y′0Z0 coordinate system, O1X1Y1Z1-O1X1Y′1Z′1 coordinate system and O2X2Y2Z2-O2X′2Y2Z′2 coordinate system are established.

[0072] Among them, O0X0Y0Z0-O0X′0Y′0Z0 is the workpiece axis, indicating that the workpiece rotates around the Z0 axis. O1X1Y1Z1-O1X1Y′1Z′1 is located on the worm grinding wheel rotation axis, which is fixed to the grinding wheel axis. The X1 axis coincides with the worm grinding wheel axis and rotates around its axis with the worm grinding wheel. O2X2Y2Z2-O2X′2Y2Z′2 represents the worm grinding wheel installation position, which rotates around the Y2 axis through the worm grinding wheel installation angle δ. At the same time, there is a tangential feed ζ, an axial feed motion h, and a radial feed ρ on the X1 axis, Z1 axis, and Y1 axis respectively to ensure accurate tool alignment between the worm grinding wheel and the workpiece. RT x (φ), RT y (δ), RT z (ψ) The transformation matrices of the three are expressed as:

[0073]

[0074]

[0075]

[0076] Where ψ is the workpiece rotation angle, and ψ is the grinding wheel rotation angle.

[0077] S3. Create a scattered point cloud of the tooth groove to be ground based on the processing information and the involute equation.

[0078] See also Figure 5 , the homogeneous coordinates of the ideal tooth surface scattered points can be obtained through the involute equation, and then a certain grinding allowance is added to the normal direction of all the ideal tooth surface scattered points, and finally the scattered point cloud of the tooth surface to be ground is obtained.

[0079] S4. Simulating machining based on the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground to obtain an undeformed chip point cloud during machining; wherein the method for obtaining the undeformed chip point cloud includes the following process:

[0080] S41. Obtain a cylindrical region of the outer edge shape of the gear to be ground.

[0081] S42. Data points within the cylindrical region of all data points of the worm grinding wheel in the workpiece coordinate system are selected as worm grinding wheel grinding points. In this embodiment, the cylindrical region of the gear shape is used to perform a first screening of the data points of the worm grinding wheel in the workpiece coordinate system, and the data points within the cylindrical region are selected as worm grinding wheel grinding points.

[0082] S43. Fit the homogeneous coordinates of the scattered point cloud of the tooth groove to be ground, and then envelop to form a three-dimensional solid area.

[0083] See also Figure 6 , the homogeneous coordinates of the scattered point cloud of the tooth groove to be ground are synthesized into a three-dimensional solid area block through the system platform.

[0084] S44. All worm grinding wheel grinding points outside the three-dimensional solid area are used as data points of undeformed chips to form an undeformed chip point cloud.

[0085] See also Figure 7 ,Since the models in the simulation all carry coordinate data, in ,the simulation process it is only necessary to determine whether the worm grinding wheel ,point belongs to the three-dimensional block synthesized in the above steps. If not, it is a data point in the ,undeformed chip.

[0086] S5. Calculate the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground, then integrate the distance to obtain the cross-sectional area of the undeformed chip, and then calculate the grinding force F at any processing point. c :

[0087]

[0088] Where μ represents the inherent parameter related to the grinding ability and material removal efficiency of the grinding wheel; b s represents the effective grinding wheel width; k is the grinding force per unit area; n is the friction factor in the grinding process; A cu is the area of the overlapping surface; l is the arbitrary contact length of the external cylindrical grinding contact arc, s is the integral upper limit of l; N d (l) is the number of dynamic grinding edges within the range of any contact length l of the external cylindrical grinding contact arc.

[0089] See also Figure 8 In this embodiment, the grinding force F c Divided into axial force Fa , normal force F n and tangential force F t , where the axial force F a The line of action is parallel to the grinding wheel axis and its value is small, so it can be ignored. t =μ·F n Since μ is a measure of the grinding ability and material removal efficiency of the grinding wheel, its value is generally in the range of 1 / 3 to 2 / 3. n The grinding force can be effectively predicted by prediction, and the grinding force Because F a Small, the grinding force can be expressed as F c =ψFn n ,in Number of dynamic grinding edges N within any contact length l of the external cylindrical grinding contact arc d (l) is:

[0090]

[0091] Where A n is the proportional coefficient. C e is the abrasive density. w and V s are the linear speed of the grinding wheel and the workpiece removal speed respectively. p is the cutting depth. e is the equivalent grinding wheel diameter. s is the contact length. α and β are indices that characterize the distribution of abrasive particles on the working surface of the grinding wheel.

[0092] In this embodiment, for cylindrical grinding, the equivalent grinding wheel diameter d e The calculation formula is:

[0093]

[0094] Where, d w is the diameter of a simulated workpiece with a circular surface, and the simulated workpiece is used to simulate the geometry of any point on the involute tooth surface of the workpiece to be machined. s The diameter of a simulated grinding wheel with a circular surface, which is used to simulate the surface of a worm grinding wheel.

[0095] Among them, the diameter d of the simulated workpiece w The expression formula is:

[0096]

[0097] Where r w is the curvature radius of the simulated workpiece. z, m n and αt are the number of teeth, module and end pressure angle of the workpiece to be processed.

[0098] Diameter d of the simulated grinding wheel s The expression formula is:

[0099]

[0100] Where d0 is the diameter at the contact point; α is the normal pressure angle.

[0101] See also Figure 9 and Figure 10 In this embodiment, the grinding force at any angle is obtained by the cross-sectional area of the undeformed chip and the grinding force calculation formula, and the complete grinding force prediction waveform of the gear grinding process is obtained by superposition; at the same time, it is known from the current obtained from the gear grinding machine processing experiment that the grinding force waveform change predicted by the simulation is roughly the same as the current.

[0102] According to the comparison of the two figures, Figure 10 The data of current collected during the experiment is shown in Figure 2. The red line represents the filtered current waveform. The horizontal axis in the image is in seconds. The grinding wheel spindle speed is 3272 rad / min. The speed unit is changed to angle. The experimental cycle is 6.853 and the simulation cycle is 6.5. The cycle is basically the same as the waveform, so the model has the function of truly predicting the grinding force waveform.

[0103] See also Figure 11 According to the grinding force calculation formula, the grinding force is related to the chip cross-sectional area and chip length. Changing the axial feed rate can change the chip length and cross-sectional area to achieve the purpose of changing the grinding force. The axial feed rate during the processing of the first tooth groove is changed. It is observed that the chip cross-sectional area, chip length and grinding force increase with the increase of the axial feed rate.

[0104] In summary, the grinding force simulation calculation method of this embodiment is based on the grinding wheel model, and the involute equation is used to obtain the ideal processed tooth surface, and a certain cutting allowance is added to this tooth surface to obtain the tooth groove to be processed. By observing the mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, the change matrix is written, and the grinding wheel homogeneous coordinates are transformed into the workpiece coordinate system to facilitate simulation processing. In the grinding force calculation process, the geometric data of the undeformed chips is extremely important, so it is necessary to obtain the undeformed chip data points, envelop the tooth groove to be processed into a solid area, and perform inclusion judgment on the grinding wheel homogeneous coordinates on the workpiece coordinate system and the solid area to obtain the data points that do not belong to this solid area, that is, the undeformed chip data points. After obtaining the data points, the distance between the data points and the tooth surface to be ground is calculated, and then a series of distance integrals are processed to obtain the cross-sectional area of the undeformed chips. Finally, the grinding force at any point is obtained by the calculation formula, and the grinding forces are superimposed at the same angle to obtain a complete grinding process simulation grinding force change waveform.

[0105] This simulation calculation method can simulate the grinding process of the worm grinding wheel and calculate the grinding force, effectively reducing the difficulty of estimating the grinding force during the worm grinding wheel grinding process. It can also analyze the correlation between the grinding force and the rotation angle of the worm grinding wheel during the worm grinding wheel grinding process, thereby providing a theoretical basis for the optimization of the structure and process parameters of the worm grinding wheel grinding machine tool.

[0106] Example 2

[0107] The present invention also discloses a computer terminal, which includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor.

[0108] The computer terminal can be a smart phone, tablet computer, laptop computer, etc. that can execute a program. In some embodiments, the processor can be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. The processor is generally used to control the overall operation of the computer device. In this embodiment, the processor is used to run the program code stored in the memory or process data. When the processor executes the program, the steps of the dynamic grinding force simulation calculation method based on the generating grinding worm in Example 1 can be implemented.

[0109] Example 3

[0110] The present invention also discloses a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the steps of the dynamic grinding force simulation calculation method based on the generating grinding worm in Example 1 can be implemented.

[0111] The computer-readable storage medium may include flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, a magnetic disk, an optical disk, etc. In some embodiments, the storage medium may be an internal storage unit of a computer device, such as a hard disk or memory of the computer device. In other embodiments, the storage medium may also be an external storage device of the computer device, such as a plug-in hard disk equipped on the computer device, a smart memory card (SMC), a secure digital (SD) card, a flash memory card, etc. Of course, the storage medium may also include both an internal storage unit of the computer device and its external storage device. In this embodiment, the memory is generally used to store the operating system and various application software installed on the computer device. In addition, the memory may also be used to temporarily store various types of data that have been output or are about to be output.

[0112] Example 4

[0113] The present invention also discloses a dynamic grinding force simulation calculation system based on a generating grinding worm, which applies the dynamic grinding force simulation calculation method based on a generating grinding worm in Example 1. The dynamic grinding force simulation calculation system includes: a data acquisition module and a calculation module.

[0114] The data acquisition module is used to first obtain the homogeneous coordinate matrix of the worm grinding wheel, and construct a coordinate conversion function that reflects the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, and then transform the homogeneous coordinates of the grinding wheel into the workpiece coordinate system. Then, according to the processing information and the involute equation, a scattered point cloud of the tooth groove to be ground is established. Then, according to the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground, simulated processing is performed to obtain the undeformed chip point cloud during the processing process.

[0115] The calculation module is used to calculate the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground, and then integrate the distance to obtain the cross-sectional area of the undeformed chip, and then calculate the grinding force of any processing point.

[0116] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0117] The above-described embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A dynamic grinding force simulation calculation method based on generating grinding worm, characterized in that: The simulation calculation method comprises the following steps: S1. Obtain the homogeneous coordinate matrix of the worm grinding wheel; S2. Constructing a coordinate conversion function that reflects the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, and then transforming the grinding wheel homogeneous coordinates into the workpiece coordinate system; S3. Establishing a scattered point cloud of the tooth groove to be ground based on the processing information and the involute equation; S4. Simulate the machining process to obtain an undeformed chip point cloud during machining based on the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground; Among them, the homogeneous coordinate Y(x) is: Where, the equation f(X) is the inverse involute equation interpolated from the involute scattered points; a 、x b 、x c 、x d Respectively represent the distance between each segment point of the axial tooth profile and the origin (0,0); r f Indicates tooth root height; D d Indicates the outer diameter of the grinding wheel; r c Indicates the fillet radius; S indicates the distance that the involute equation needs to be translated; The method for obtaining the undeformed chip point cloud includes the following steps: S41 obtains the cylindrical region of the outer edge of the gear to be ground; S42. The data points of the worm grinding wheel in the workpiece coordinate system located in the cylindrical region are used as worm grinding wheel grinding points; S43. Fitting the homogeneous coordinates of the scattered point cloud of the tooth groove to be ground, thereby enveloping a three-dimensional solid area; S44. All worm grinding wheel grinding points outside the three-dimensional solid area are used as data points of undeformed chips to form the undeformed chip point cloud; S5. Calculate the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground, integrate the distance to obtain the cross-sectional area of the undeformed chip, and then calculate the grinding force of any processing point.

2. The dynamic grinding force simulation calculation method based on generating grinding worm according to claim 1 is characterized in that: In S1, the method for obtaining the homogeneous coordinate matrix of the worm grinding wheel includes the following process: Setting the three-dimensional homogeneous coordinates of the axial tooth profile of the worm grinding wheel and a spiral matrix for describing the spiral transformation motion; The three-dimensional homogeneous coordinates of the axial tooth profile are multiplied by the spiral matrix to obtain the secondary coordinate matrix of the worm grinding wheel.

3. The dynamic grinding force simulation calculation method based on generating grinding worm according to claim 1 is characterized in that: In S2, the expression of the coordinate conversion function is: M(t,ω,φ)=RT x (φ)·RT y (d)·RT z (ψ)·W(t,ω) Where W(t,ω) represents the homogeneous coordinates of any point on the worm grinding wheel model, M(t,ω,φ) represents the homogeneous coordinates of the point mapped to the workpiece coordinate system; RT y (δ) represents the transformation matrix from the grinding wheel coordinate system to a tool coordinate system; RT x (φ) represents the transformation matrix from the tool setting coordinate system to the machine tool reference coordinate system; RT z (ψ) represents the coordinate matrix from the machine tool's reference coordinate system to the workpiece coordinate system.

4. The dynamic grinding force simulation calculation method based on generating grinding worm according to claim 1 is characterized in that: In S3, the homogeneous coordinates of the scattered points on the ideal tooth surface are obtained through an involute equation, and then the predetermined grinding allowance is added to the normal direction of all the scattered points on the ideal tooth surface, and finally the scattered point cloud of the tooth groove to be ground is obtained.

5. The dynamic grinding force simulation calculation method based on generating grinding worm according to claim 1 is characterized in that: In S5, the grinding force F at any processing point c The expression formula is: Where μ represents the inherent parameter related to the grinding ability and material removal efficiency of the grinding wheel; b s represents the effective grinding wheel width; k is the grinding force per unit area; n is the friction factor in the grinding process; A cu is the area of the overlapping surface; l is the arbitrary contact length of the contact arc in cylindrical grinding, and s is the integral upper limit of l; N d (l) is the number of dynamic grinding edges within the range of any contact length l of the external cylindrical grinding contact arc.

6. The dynamic grinding force simulation calculation method based on generating grinding worm according to claim 5 is characterized in that: The number N of dynamic grinding edges within the range of any contact arc length l of the cylindrical grinding contact arc d The expression formula of (l) is: Where A n is the proportional coefficient; C e is the abrasive density; V w and V s are the linear speed of the grinding wheel and the workpiece removal speed respectively; a p is the cutting depth; d e is the equivalent grinding wheel diameter; l s is the contact length; α and β are indices that characterize the distribution of abrasive particles on the working surface of the grinding wheel.

7. The dynamic grinding force simulation calculation method based on generating grinding worm according to claim 6 is characterized in that: For external cylindrical grinding, the equivalent grinding wheel diameter d e The calculation formula is: Where, d w is the diameter of a simulated workpiece with a circular surface, and the simulated workpiece is used to simulate the geometric shape of any point on the involute tooth surface of the workpiece to be processed; d s is the diameter of a simulated grinding wheel with a circular surface, and the simulated grinding wheel is used to simulate the surface of the worm grinding wheel.

8. A computer terminal comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the dynamic grinding force simulation calculation method based on generating grinding worm according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the dynamic grinding force simulation calculation method based on generating grinding worm according to any one of claims 1 to 7 are implemented.

10. A dynamic grinding force simulation calculation system based on generating grinding worm, characterized in that: The application is the dynamic grinding force simulation calculation method based on generating grinding worm as claimed in any one of claims 1 to 7; The dynamic grinding force simulation calculation system includes: a data acquisition module, which is used to first obtain the homogeneous coordinate matrix of the worm grinding wheel, and construct a coordinate conversion function reflecting the coordinate mapping relationship between the grinding wheel coordinate system and the workpiece coordinate system, transform the grinding wheel homogeneous coordinates into the workpiece coordinate system, and then establish a scattered point cloud of the tooth groove to be ground based on the processing information and the involute equation, and then perform simulated processing based on the homogeneous coordinates of the worm grinding wheel in the workpiece coordinate system and the scattered point cloud of the tooth groove to be ground to obtain an undeformed chip point cloud during the processing; as well as A calculation module is used to calculate the distance between the data point in the undeformed chip point cloud and the tooth groove to be ground, and then integrate the distance to obtain the cross-sectional area of the undeformed chip, and then calculate the grinding force of any processing point.

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