WO2023232011A1 - Fit tolerance determination method and apparatus, electronic device, and storage medium - Google Patents

Abstract

The present application discloses a fit tolerance determination method and apparatus, an electronic device, and a storage medium. The method comprises: constructing a finite element model on the basis of a transmission input shaft, a motor output shaft, a first bearing, a second bearing and a third bearing, and performing grid division on contact components among the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing to obtain at least one refined grid to be used; applying different acting forces to the finite element model, and determining a radial deformation of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different acting forces; determining a target deformation on the basis of the radial deformation; and determining a fit tolerance between the transmission input shaft and the motor output shaft on the basis of the target deformation.

Description

Fit tolerance determination method, device, electronic equipment and storage medium

This application claims priority to the Chinese patent application with application number 202210616091.6, which was submitted to the China Patent Office on May 31, 2022. The entire content of this application is incorporated into this application by reference.

Technical field

The present application relates to the field of computer processing technology, for example, to a method, device, electronic equipment and storage medium for determining fit tolerance.

Background technique

The three-bearing motor transmission refers to a transmission with a three-bearing structural assembly. In the design process of the three-bearing motor transmission product, in order to optimize the performance of the three-bearing motor transmission, the most suitable shaft space is usually defined for the three-bearing motor transmission. Fitting tolerance so that the motor output shaft and the transmission input shaft fit based on the fitting tolerance.

The method of determining the fit tolerance between shafts in the related art is usually based on the personal experience of engineers to determine the fit tolerance, and then use simulation test technology to test the performance of the three-bearing motor transmission based on the fit tolerance. This fit determined based on personal experience Poor tolerance accuracy leads to poor simulation test accuracy and low efficiency, which leads to long simulation test cycles and wastes a lot of production and development costs.

Contents of the invention

This application provides a method, device, electronic equipment and storage medium for determining fit tolerances, so as to achieve the technical effect of improving test accuracy and efficiency while improving the accuracy of determining fit tolerances between shafts.

According to one aspect of the present application, a method for determining fit tolerance is provided, which method includes:

Based on the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing, a finite element model is constructed, and the transmission input shaft, the motor output shaft, the first bearing, the second bearing are The contact components between the bearing and the third bearing are meshed to obtain at least one refined mesh to be used;

Apply different forces to the finite element model to determine the radial deformation amount of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces; wherein, the radial The direction of the deformation amount is perpendicular to the bottom surface of the corresponding axis;

Based on the radial deformation amount, determine the target deformation amount;

Based on the target deformation amount, a fit tolerance between the transmission input shaft and the motor output shaft is determined.

According to another aspect of the present application, a fitting tolerance determining device is provided, which device includes:

The refined mesh determination module to be used is configured to construct a finite element model based on the transmission input shaft, the motor output shaft, the first bearing, the second bearing, and the third bearing, and calculate the transmission input shaft, the motor output shaft , meshing the contact components between the first bearing, the second bearing and the third bearing to obtain at least one refined mesh to be used;

A radial deformation amount determination module is configured to apply different forces to the finite element model, and determine the radial diameter of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces. The amount of radial deformation; wherein the direction of the amount of radial deformation is perpendicular to the bottom surface of the corresponding axis;

The target deformation amount determination module is configured to determine the target deformation amount based on the radial deformation amount;

A fitting tolerance determination module is configured to determine a fitting tolerance between the transmission input shaft and the motor output shaft based on the target deformation amount.

According to another aspect of the present application, an electronic device is provided, the electronic device including:

at least one processor; and

a memory communicatively connected to the at least one processor; wherein,

The memory stores a computer program that can be executed by the at least one processor, and the computer program is executed by the at least one processor, so that the at least one processor can execute the method described in any embodiment of the present application. Method for determining fit tolerances.

According to another aspect of the present application, a computer-readable storage medium is provided. The computer-readable storage medium stores computer instructions, and the computer instructions are used to implement any of the embodiments of the present application when executed by a processor. method for determining fit tolerances.

Description of the drawings

The drawings needed to be used in the description of the embodiments will be briefly introduced below. The drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without exerting any creative effort, , other drawings can also be obtained based on these drawings.

Figure 1 is a flow chart of a method for determining fit tolerances provided according to Embodiment 1 of the present application;

Figure 2 is a schematic diagram of a three-bearing structure provided according to Embodiment 1 of the present application;

Figure 3 is a schematic diagram of a spline position grid provided according to Embodiment 1 of the present application;

Figure 4 is a schematic diagram of the spline axis symmetry of the motor output shaft provided according to Embodiment 1 of the present application;

Figure 5 is a schematic diagram of mesh partitioning refinement of a single spline tooth surface provided according to Embodiment 1 of the present application;

Figure 6 is a schematic diagram of the bearing geometric structure provided according to Embodiment 1 of the present application;

Figure 7 is a schematic diagram of the geometric structure of the bearing outer ring provided according to Embodiment 1 of the present application;

Figure 8 is a schematic diagram of establishing an RBE3 unit based on the outer surface of the bearing provided in Embodiment 1 of the present application;

Figure 9 is a schematic diagram of the geometric structure of the motor output shaft provided according to Embodiment 1 of the present application;

Figure 10 is a schematic diagram of establishing an RBE3 unit based on the outer surface of the motor shaft provided in Embodiment 1 of the present application;

Figure 11 is a schematic cross-sectional view of the transmission input shaft provided according to Embodiment 1 of the present application;

Figure 12 is a schematic diagram of establishing an RBE3 unit based on the gear meshing point of the transmission input shaft provided in Embodiment 1 of the present application;

Figure 13 is a schematic cross-sectional view of the motor output shaft provided according to Embodiment 1 of the present application;

Figure 14 is a schematic structural diagram of a fitting tolerance determining device provided according to Embodiment 3 of the present application;

Figure 15 is a schematic structural diagram of an electronic device that implements the fit tolerance determination method according to the embodiment of the present application.

In the picture,

210. Transmission input shaft; 2101. Transmission input shaft spline; 2102. Follower point (primary driving gear meshing node); 2103. Nearby tooth surface; 2104. Tooth surface; 2105. RBE3 unit; 2106. Shaft inner wall;

220. First bearing; 2201. Bearing outer ring; 2202. Master point; 2203. Slave point; 2204. Cylindrical coordinate system; 2205. RBE3 unit;

230. Second bearing;

240. The third bearing;

250. Motor output shaft; 2501. Motor output shaft spline; 25011. Refined grid of spline tooth surface; 25012. Coarse grid of spline tooth surface; 2502. Principal point; 2503. Cylindrical coordinate system; 2504. RBE3 Unit; 2505, from point; 2506, shaft outer wall;

Detailed ways

The embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present application. As mentioned above, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts should fall within the scope of protection of this application.

It should be noted that the terms "first", "second", "target" and "original" in the description and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to distinguish them. Describe a specific order or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances so that the embodiments of the application described herein can be practiced in sequences other than those illustrated or described herein. In addition, the terms "include", "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or units may include no Other steps or units that are clearly listed or inherent to such processes, methods, products or devices.

Embodiment 1

Figure 1 is a flow chart of a method for determining a fit tolerance provided according to Embodiment 1 of the present application. This embodiment can be applied to the situation of determining the fit tolerance between shafts. The method can be executed by a fit tolerance determining device. The fit tolerance determines The device may be implemented in the form of hardware and/or software, and the fit tolerance determining device may be configured in a computing device. As shown in Figure 1, the method includes:

S110. Construct a finite element model based on the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing, and model the transmission input shaft, the motor output shaft, the first bearing, the The contact components between the second bearing and the third bearing are meshed to obtain at least one refined mesh to be used.

In practical applications, a finite element model of a three-bearing structure assembly can be established. For example, the three-bearing structure includes a transmission input shaft, a motor output shaft, a first bearing, a second bearing, a third bearing, etc. You can refer to Figure 2, Figure 2 can be represented as a schematic diagram of a three-bearing structure. The transmission input shaft 210, the motor output shaft 250, the first bearing 220, the second bearing 230 and the third bearing 240 together form a three-bearing structure. All components in the three-bearing structure can be meshed, and the divided meshes can be assembled together to construct a finite element model. When meshing, the contact components between the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing can be meshed in a refined manner to obtain at least one refined mesh to be used, The remaining part of the structure can be coarsely meshed to obtain at least one coarse mesh. It can be understood that the refined mesh to be used has a smaller volume than the coarse mesh. Illustratively, the transmission input shaft and the motor output shaft rely on splines for contact. Refer to Figure 3. Figure 3 can be represented as a spline position grid diagram. The motor output shaft spline 2501 and the transmission input shaft spline can be The 2101 tooth surface grid is divided into zones, and the middle of the spline tooth surface is refined and the two ends are refined to form a spline tooth surface refined grid and a spline tooth surface coarsened grid. In the actual modeling process, as shown in Figure 4, it can be expressed as a symmetrical diagram of the motor shaft spline, then the motor output shaft spline 2501 and the transmission input Shaft spline 2101 can be modeled using axial symmetry based on the symmetry characteristics of the spline. For example, only a single spline tooth surface mesh is established. See Figure 5. One spline tooth surface in the motor output shaft spline 2501 can be divided into The spline tooth surface refined grid 25011 (that is, the refined grid to be used) and the spline tooth surface coarsened grid 25012 can then establish a complete spline grid model through axial symmetry. Correspondingly, the finite element model of the complete three-bearing structural assembly can be obtained.

It should be noted that in order to improve the accuracy of constructing the finite element model of the three-bearing structure, mechanical property parameters can be added to the finite element model, such as material properties or strains, deformation gradients, etc., so that the mechanical property parameters corresponding to each grid can be Characterize the actual mechanical properties of the corresponding component.

Optionally, the method further includes: determining mechanical property data corresponding to the finite element model; and updating the finite element model based on the mechanical property data.

Among them, the mechanical property data includes material property data and structural property data.

In practical applications, corresponding mechanical property data can be defined for the finite element model. For example, the elastic modulus of the finite element model is defined as E=210000MPa, Poisson's ratio μ=0.3, and all finite element models have mechanical properties such as linear elastic materials. The finite element model can be updated based on the defined mechanical property data to obtain a finite element model with mechanical properties.

It should be noted that in order to prevent rigid body displacement of the model and better meet the conditions for finite element solution, you can define constraints for the finite element model when establishing the finite element model. For example, when applying loads to the finite element model, you can Limit the rotation of certain components in the three-bearing structure.

Optionally, the method further includes: determining a first model boundary condition and a second model boundary condition corresponding to the finite element model; and updating the finite element model based on the first model boundary condition and the second model boundary condition.

Wherein, the first model boundary condition is determined based on the fixed first bearing, the second bearing and the third bearing, for example, all degrees of freedom of the fixed bearing except the axial rotational degree of freedom. The second model boundary condition is determined based on a fixed motor output shaft, for example, a fixed motor output shaft axial rotational degree of freedom.

In practical applications, boundary restriction conditions can be imposed on the finite element model, and the model boundary restriction conditions can be divided into two categories: one is the first model boundary condition, and the other is the second model boundary condition. For example, when applying the first model boundary condition, that is, fixing all the degrees of freedom of the bearing except the axial rotational freedom, the outer rings of the first bearing, the second bearing, and the third bearing can be fixed to simulate the transmission and motor housing. The body supports the bearing. Taking the first bearing as an example to illustrate the fixing process of the bearing outer ring, as shown in Figure 6, it can be represented as a schematic diagram of the bearing geometric structure. When fixing the bearing outer ring 2201, it needs to be applied with the help of the RBE3 unit, as shown in Figure 7, which can be represented For the schematic diagram of the geometric structure of the bearing outer ring, the main point 2202 of the RBE3 unit selects the outer ring surface of the bearing outer ring 2201, and the bearing geometric center is selected from point 2203. As shown in Figure 8, it can be expressed as the schematic diagram of the RBE3 unit established for the outer surface of the bearing, RBE3 Unit 2205 from point 2203 The 6 o'clock degree of freedom around the cylindrical coordinate system 2204 is not constrained, and all other degrees of freedom are constrained. The Z axis of the cylindrical coordinate system 2204 is along the gear axis axis direction, the R axis is along the radial direction of the gear axis, and the t axis is determined by Z and R according to The right hand criterion is determined. When applying the second model boundary condition, that is, fixing the axial rotational freedom of the motor output shaft, for example, see Figure 9. Figure 9 can be represented as a schematic diagram of the geometric structure of the motor output shaft. When fixing the motor output shaft 250, it is necessary to use RBE3 unit application, as shown in Figure 10, can be expressed as a schematic diagram of establishing an RBE3 unit for the outer surface of the motor shaft. The main point 2502 of the RBE3 unit 2504 selects the outer surface of the motor output shaft 250, and the geometric center of the motor output shaft 250 is selected from point 2505. Only constraints are applied. RBE3 element 2504 has a 6 o'clock degree of freedom from point 2505 about cylindrical coordinate system 2503. In the process of force analysis of the finite element model, all degrees of freedom of the fixed bearing except the axial rotational freedom, as well as the axial rotational freedom of the fixed motor output shaft, are used to improve the accuracy of the model analysis.

S120. Apply different forces to the finite element model, and determine the radial deformation amount of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces.

Among them, the acting force can be understood as load. Optionally, the acting force includes bearing interference force, transmission gear meshing force and motor eccentric load. The transmission gear meshing force is based on the gear pitch circle diameter of the transmission input shaft, gear transmission torque, gear The normal pressure angle and the helix angle at the gear pitch circle are determined. The bearing interference force can be understood as the interference force between the contact areas of the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing. The eccentric load of the motor can be understood as the radial electromagnetic force. The direction of the radial deformation is perpendicular to the bottom surface of the corresponding axis.

In practical applications, at least one of the bearing interference force, transmission gear meshing force and motor eccentric load can be applied to the finite element model. In this way, each grid in the finite element model may produce corresponding deformations, and the transmission input can be obtained. The radial deformation amount of each refined mesh to be used at the shaft and the motor output shaft under different kinds of forces is used to determine the fit tolerance between the transmission input shaft and the motor output shaft based on the radial deformation amount.

It should be noted that in order to improve the accuracy of the fit tolerance calculation, different test conditions can be designed and different forces can be applied under different test conditions. Correspondingly, the refinement of each to be used under different test conditions can be obtained. The radial deformation amount of the grid, for example, can be three test conditions, which can be: preload condition, gear force condition, and eccentric force condition. The boundary conditions used in the three test conditions are the first model boundary condition and the second model boundary condition. Among them, when performing the preload condition test, only the interference amount of the bearing inner ring, that is, the bearing interference force, can be applied, and the transmission gear meshing force and motor eccentric load are not applied. When performing the gear force condition test, the transmission gear meshing force can be applied based on the preload condition. When performing the eccentric force condition test, the motor eccentric load can be applied based on the preload condition. The implementation methods of the three test conditions are described in detail below:

When performing the preload condition test, optionally apply different forces to the finite element model to determine the radial direction of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces. The deformation amount includes: applying a bearing interference force to the second bearing in the finite element model to obtain the radial deformation amount of each refined mesh to be used corresponding to the shaft inner wall of the transmission input shaft at the second bearing position.

It should be noted that, taking into account the calculation accuracy and calculation convergence of interference contact between shafts, when cutting the contact areas of the transmission input shaft, motor output shaft, first bearing, second bearing and third bearing, a In the regular geometric area, the corresponding interference contact relationship can be established at the contact part grid, that is, the corresponding bearing interference force can be set.

In practical applications, in order to improve calculation efficiency, the bearing interference force can be applied to the second bearing in the finite element model, and then the finite element model calculation and analysis of the three-bearing structure can be performed. The time period of each test condition can be averaged Set to 1, the time increment is set to 0.1, and the Newton-Raphson method is used to iteratively calculate and output the analysis results of the three-bearing finite element model during the preload condition test. Optionally, the analysis results can be processed to extract the radial deformation amount of each refined grid to be used on the shaft inner wall (ie, shaft inner surface) of the transmission input shaft at the position corresponding to the second bearing position, for example, see Figure 11. Figure 11 can be represented as a schematic cross-sectional view of the transmission input shaft, and the radial deformation amount of each refinement grid to be used on the shaft inner wall 2106 of the transmission input shaft 210 corresponding to the second bearing position can be obtained.

When performing the gear force condition test, optionally, apply different forces to the finite element model to determine the radial shape of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces. Variables include: determining the gear meshing node based on the gear pitch circle diameter of the transmission input shaft in the finite element model; applying the transmission gear meshing force to the gear meshing node when applying the bearing interference force to the second bearing in the finite element model , obtain the radial deformation amount corresponding to the shaft inner wall of the transmission input shaft at the second bearing position, and the radial deformation amount corresponding to the shaft outer wall of the motor output shaft at the second bearing position.

In practical applications, the gear meshing node can be determined based on the gear pitch circle diameter of the transmission input shaft in the finite element model. For example, see Figure 12. Figure 12 can be shown as a schematic diagram of establishing an RBE3 unit for the gear meshing point of the transmission input shaft. It can be The slave point 2102 of the RBE3 unit 2105 is used as the first-level driving gear meshing node. The unit nodes on the nearby tooth surfaces 2103 and 2104 are the main points of the RBE3 unit 2105. The first-level driving gear meshing node 2102 can be used as the transmission gear meshing force. The node applied at is the gear mesh node, which is on the gear pitch circle diameter. When determining the gear meshing force, the gear meshing force can be calculated according to formula (1) based on the gear transmission torque M of the transmission input shaft, gear meshing parameters and gear load. Formula (1) is as follows:

The gear meshing force includes the circumferential force F _t , radial force _Fr and axial force _Fa of the gear, which can be applied with the help of a local cylindrical coordinate system defined on the axis of the transmission input shaft. M is the torque transmitted by the gear, That is, the gear transmits torque, d is the gear pitch circle diameter, α _n is the gear normal pressure angle, and β is the helix angle at the gear pitch circle. When the bearing interference force is applied to the second bearing in the finite element model, the transmission gear meshing force can be applied to the gear meshing node, and then the finite element model can be calculated and analyzed for the three-bearing structure, and the Newton-Raphson method can be used to iterate Calculate and output the analysis results of the three-bearing finite element model during the gear force condition test. Optionally, the analysis results can be processed to extract the radial deformation amount corresponding to the shaft inner wall (i.e., the inner surface) of the transmission input shaft at the second bearing position, and the shaft outer wall (i.e., the motor output shaft) at the second bearing position. The amount of radial deformation corresponding to the outer surface), for example, see Figure 13. Figure 13 can be represented as a schematic cross-sectional view of the motor output shaft, wherein the mark 2506 in Figure 13 can be represented as the position of the motor output shaft 250 corresponding to the second bearing position. The outer wall of the shaft 2506.

When performing the eccentric force condition test, optionally, apply different forces to the finite element model to determine the radial shape of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces. Variables include: determining the motor load starting point of the motor output shaft in the finite element model; when applying the bearing interference force to the second bearing in the finite element model, applying the motor eccentric load to the motor load starting point to obtain the transmission input shaft at the third The radial deformation amount corresponding to the shaft inner wall at the second bearing position, and the radial deformation amount corresponding to the shaft outer wall of the motor output shaft at the second bearing position.

In practical applications, the RBE3 unit can be used to determine the slave point of the RBE3 unit as the motor load slave point of the motor output shaft in the finite element model. When applying a bearing interference force to the second bearing in the finite element model, an eccentric load can be applied to the motor load from a point. For example, continuing to refer to Figure 10, the eccentric load F (maximum single load) suffered by the motor output shaft during operation can be Edge magnetic pulling force) is exerted on the slave point 2505 of the RBE3 unit 2504 in a static load manner, and the eccentric load direction is the R-axis direction of the cylindrical coordinate system 2503. Optionally, the finite element model can be calculated and analyzed for the three-bearing structure, and the Newton-Raphson method can be used to iteratively calculate and output the analysis results of the three-bearing finite element model during the eccentric force condition test. The analysis results can be processed to extract the radial deformation amount corresponding to the shaft inner wall (ie, the inner surface) of the transmission input shaft at the second bearing position, and the radial deformation amount corresponding to the shaft outer wall (ie, the outer surface) of the motor output shaft at the second bearing position. The corresponding radial deformation amount.

S130. Based on the radial deformation amount, determine the target deformation amount.

In practical applications, the radial deformation amount can be processed to obtain the target deformation amount used to determine the fit tolerance. For example, the corresponding radial deformation amount to be used can be determined from the radial deformation amount under each test condition. variables, and then determine the target deformation amount based on the determined radial deformation amount to be used.

Optionally, determine the minimum radial deformation amount of the shaft inner wall of the transmission input shaft at the second bearing position under different acting forces; and determine the maximum diameter of the shaft outer wall of the motor output shaft at the second bearing position under different acting forces. radial deformation amount; determine the target deformation amount based on the minimum radial deformation amount and the maximum radial deformation amount.

In practical applications, for the preload condition test, the transmission input shaft can be extracted from the second bearing The smallest radial deformation amount among the radial deformation amounts corresponding to the inner wall of the shaft at the second bearing position is recorded as u ₁ ; for the gear force condition test, the radial deformation amount corresponding to the inner wall of the shaft inner wall of the transmission input shaft at the second bearing position can be extracted The smallest radial deformation amount among the deformations is recorded as u ₂ , and the largest radial deformation amount among the radial deformation amounts corresponding to the shaft outer wall of the motor output shaft at the second bearing position is recorded as u ₃ ; for the eccentric force Under the working condition test, the smallest radial deformation amount corresponding to the inner shaft wall of the transmission input shaft at the second bearing position can be extracted, recorded as u ₄ , and the outer shaft wall of the motor output shaft at the second bearing position. The largest radial deformation amount among the corresponding radial deformation amounts is recorded as u ₅ . The radial deformation obtained under the three working conditions can be calculated according to formula (2), and the target deformation under the joint action of bearing interference, gear force and eccentric force is obtained, recorded as, formula (2) is as follows:
U=∑|u _i |, (i=1, 2,…,5) (2)

Among them, U can be expressed as the target deformation amount, u _i , (i=1,2,...,5) are the corresponding radial deformation amounts obtained under the three test conditions.

S140. Based on the target deformation amount, determine the fitting tolerance between the transmission input shaft and the motor output shaft.

In practical applications, the inter-shaft fit tolerance of the motor output shaft and the transmission input shaft in the three-bearing structure at the position corresponding to the intermediate bearing can be determined based on the target deformation amount. Optionally, the inter-shaft fit tolerance should be greater than the obtained target deformation amount. U.

This embodiment obtains at least one refined mesh to be used by meshing the contact components between the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing in the finite element model, and Apply different kinds of forces to the finite element model, determine the radial deformation amount of the refined mesh to be used corresponding to the transmission input shaft and the motor output shaft under different forces, and determine the target deformation amount based on the radial deformation amount, Then, based on the target deformation amount, the fitting tolerance between the transmission input shaft and the motor output shaft is determined, which solves the problem in the related technology of determining the fitting tolerance between the shafts of the three-bearing structure based on manual experience, resulting in low accuracy in determining the fitting tolerance, and realizes In order to determine the corresponding radial deformation amounts of the transmission input shaft and the motor output shaft under different kinds of forces when applying different kinds of forces to the finite element model, combined with different test conditions, based on the According to the radial deformation amount, the target deformation amount is determined, and the fitting tolerance between the shafts of the three-bearing structure is determined based on the target deformation amount. While improving the accuracy of determining the fitting tolerance between the shafts, it also achieves the technical effect of improving the test accuracy and efficiency.

Embodiment 2

As an optional embodiment of the above embodiment, in order to make the technical solution of the embodiment of the present application clear to those skilled in the art, a specific application scenario example is given. For details, please refer to the following specific content.

For example, continuing to refer to Figure 2, a finite element model of the three-bearing structural assembly can be established, respectively All components in the three-bearing structure are meshed. The three-bearing structure includes the transmission input shaft 210, the motor output shaft 250, the first bearing 220, the second bearing 230 and the third bearing 240, and the divided mesh is assembled on Together, a finite element model is constructed. When meshing, the contact components between the transmission input shaft 210, the motor output shaft 250, the first bearing 220, the second bearing 230 and the third bearing 240 can be meshed in a refined manner to obtain at least one to be used. To refine the mesh, coarse mesh can be performed on the remaining part of the structure to obtain at least one coarse mesh. For example, the transmission input shaft and the motor output shaft are contacted by splines. You can continue to refer to Figure 3. Taking into account both calculation accuracy and calculation speed, the motor output shaft spline 2501 and the transmission input shaft spline 2101 can be connected. The surface mesh is partitioned and meshed, and the middle of the spline tooth surface is refined and the two ends are refined to form a spline tooth surface refined mesh and a spline tooth surface coarsened mesh. In the actual modeling process, you can continue to refer to Figure 4. Both the motor output shaft spline 2501 and the transmission input shaft spline 2101 can be modeled using axial symmetry based on the symmetrical characteristics of the spline. For example, only a single spline tooth surface is established. Grid, continue to refer to Figure 5. One spline tooth surface in the motor output shaft spline 2501 can be divided into a spline tooth surface refined grid 25011 (that is, the refined grid to be used) and a spline tooth surface coarsening grid. Grid 25012, and then a complete spline grid model can be established through axial symmetry. Taking into account the calculation accuracy and calculation convergence of interference contact, the transmission input shaft 210, the motor output shaft 250, the first bearing 220, the second The contact area of the bearing 230 and the third bearing 240 is cut to form a regular geometric area, so that the unit nodes of the contact part grid correspond one to one, and a corresponding interference contact relationship is established.

On the basis of the above scheme, the elastic modulus of the finite element model can be defined as E=210000MPa and Poisson's ratio μ=0.3. All finite element models are linear elastic materials and other mechanical property data, and finite element model boundary conditions can also be applied. That is, the first model boundary condition and the second model boundary condition, where the first model boundary condition is all the degrees of freedom of the fixed bearing except the axial rotational degree of freedom. The second model boundary condition is to fix the axial rotational freedom of the motor output shaft. It should be noted that the first model boundary condition and the second model boundary condition can separately constrain the finite element model. For example, continue to refer to Figure 6. When fixing the bearing outer ring 2201 in Figure 6, it needs to be applied with the help of the RBE3 unit. Continue to refer to Figure 7. The main point 2202 of the RBE3 unit selects the outer ring surface of the bearing outer ring 2201, and the bearing outer ring 2201 is selected from the point 2203. For the geometric center, continue to refer to Figure 8. When the boundary is constrained, the degree of freedom of the RBE3 unit from point 2203 around the 6 o'clock direction of the cylindrical coordinate system 2204 is not constrained, and all other degrees of freedom are constrained. The Z axis of the cylindrical coordinate system 2204 is along the gear The axis axis direction, the R axis is along the radial direction of the gear axis, and the t axis is determined by Z and R according to the right-hand criterion. When the axial rotational freedom of the motor output shaft 250 is fixed, continue to refer to Figure 9 and need to be applied with the help of the RBE3 unit. Continue to refer to Figure 10. The main point 2502 of the RBE3 unit 2504 selects the outer surface of the motor output shaft 250, and the slave point 2505 selects the motor output. The geometric center of the axis 250, when bounded, can only constrain the 6 o'clock degree of freedom of the RBE3 unit 2504 from the point 2505 around the cylindrical coordinate system 2503. In the process of force analysis of the finite element model, all degrees of freedom of the fixed bearing except the axial rotational freedom, as well as the axial rotational freedom of the fixed motor output shaft, are used to improve the accuracy of the model analysis.

On the basis of the above scheme, different test conditions can be designed, and different forces can be applied under different test conditions. Correspondingly, the radial deformation amount of each refined mesh to be used under different test conditions can be obtained. , for example, the test conditions can be respectively: preload condition, gear force condition, and eccentric force condition. The boundary conditions used in these three test conditions are the first model boundary condition and the second model boundary condition. Among them, when performing the preload condition test, only the interference amount of the bearing inner ring, that is, the bearing interference force, can be applied, and the transmission gear meshing force and motor eccentric load are not applied. When performing the gear force condition test, the transmission gear meshing force can be applied on the basis of the preload condition. For example, continuing to refer to Figure 12, the first-level driving gear meshing node 2102 can be the slave point of the RBE3 unit 2105, and the nearby teeth The unit nodes on the surface 2103 and the tooth surface 2104 are the main points of the RBE3 unit 2105. The primary driving gear meshing node 2102 can be used as the node where the transmission gear meshing force needs to be applied, that is, the gear meshing node. The gear meshing node is at the gear node. circle diameter. When determining the gear meshing force of the transmission, the gear meshing force can be calculated according to formula (1) based on the gear transmission torque of the transmission input shaft, gear meshing parameters and gear load. Formula (1) is as follows:

The gear meshing force includes the circumferential force F _t , radial force _Fr and axial force _Fa of the gear, which can be applied with the help of a local cylindrical coordinate system defined on the axis of the transmission input shaft. M is the torque transmitted by the gear, that is, the torque transmitted by the gear, d is the gear pitch circle diameter, α _n is the gear normal pressure angle, and β is the helix angle at the gear pitch circle. When performing the eccentric force condition test, the motor eccentric load can be applied on the basis of the preload condition. For example, continuing to refer to Figure 10, the eccentric load F (maximum unilateral magnetic pull force) received by the motor output shaft during operation can be ) is applied as a static load on the slave point 2505 of the RBE3 unit 2504, and the eccentric load direction is the R-axis direction of the cylindrical coordinate system 2503. The time period of each test condition can be set to 1, the time increment can be set to 0.1, and the Newton-Raphson method can be used to iteratively calculate and output the analysis results of the three-bearing finite element model during the three test conditions. The smallest radial deformation amount corresponding to the inner wall of the shaft inner wall of the transmission input shaft at the second bearing position can be extracted, recorded as u ₁ ; for the gear force condition test, the transmission input shaft at the second bearing position can be extracted The smallest radial deformation amount corresponding to the radial deformation amount of the shaft inner wall at the second bearing position, recorded as u ₂ , and the largest radial deformation amount corresponding to the radial deformation amount of the motor output shaft at the second bearing position. , recorded as u ₃ ; for the eccentric force condition test, the smallest radial deformation amount corresponding to the inner wall of the shaft inner wall of the transmission input shaft at the second bearing position can be extracted, recorded as u ₄ , and the motor output The largest radial deformation amount among the radial deformation amounts corresponding to the outer wall of the shaft at the second bearing position is recorded as u ₅ . The radial deformation obtained in the three working conditions can be calculated according to formula (2), and the target deformation under the joint action of bearing interference, gear force and eccentric force is obtained, recorded as, formula (2) is as follows:
U=∑|u _i |, (i=1, 2,…,5) (2)

Among them, U can be expressed as the target deformation amount, u _i , (i=1,2,...,5) are the corresponding radial deformation amounts obtained under the three test conditions. Optionally, the inter-shaft fit tolerance of the motor output shaft and the transmission input shaft in the three-bearing structure at the position corresponding to the intermediate bearing can be determined based on the target deformation amount. Optionally, the inter-shaft fit tolerance should be greater than the obtained target deformation amount U. .

This embodiment obtains at least one refined mesh to be used by meshing the contact components between the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing in the finite element model, and Apply different kinds of forces to the finite element model, determine the radial deformation amount of each refined mesh corresponding to the transmission input shaft and the motor output shaft under different forces, and determine the target deformation based on the radial deformation amount. variables, and then based on the target deformation amount, the fit tolerance between the transmission input shaft and the motor output shaft is determined, which solves the problem in related technologies that the fit tolerance between the shafts of the three-bearing structure is determined based on manual experience, resulting in low accuracy in determining the fit tolerance. , it is possible to determine the radial deformation amounts of the transmission input shaft and the motor output shaft under different forces when different forces are applied to the finite element model. It combines different test conditions and based on each test condition According to the radial deformation under the condition, the target deformation is determined, and the fitting tolerance between the shafts of the three-bearing structure is determined based on the target deformation. While improving the accuracy of determining the fitting tolerance between the shafts, it also achieves the technical effect of improving the test accuracy and efficiency.

Embodiment 3

Figure 14 is a schematic structural diagram of a fitting tolerance determining device provided according to Embodiment 3 of the present application. As shown in Figure 14, the device includes: a refined mesh to be used determining module 410, a radial deformation amount determining module 420, a target deformation amount determining module 430 and a fit tolerance determining module 440.

Among them, the refined mesh determination module 410 to be used is configured to construct a finite element model based on the transmission input shaft, the motor output shaft, the first bearing, the second bearing, and the third bearing, and calculate the transmission input shaft, the The contact components between the motor output shaft, the first bearing, the second bearing and the third bearing are meshed to obtain at least one refined mesh to be used;

The radial deformation amount determination module 420 is configured to apply different forces to the finite element model, and determine the parameters of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces. The amount of radial deformation; wherein the direction of the amount of radial deformation is perpendicular to the bottom surface of the corresponding axis;

The target deformation amount determination module 430 is configured to determine the target deformation amount based on the radial deformation amount;

The fitting tolerance determination module 440 is configured to determine the fitting tolerance between the transmission input shaft and the motor output shaft based on the target deformation amount.

In this embodiment, by meshing the contact parts between the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing in the finite element model, at least one refinement to be used is obtained. grid, and apply different kinds of forces to the finite element model to determine the radial deformation amount of each refined grid corresponding to the transmission input shaft and the motor output shaft under different forces. Based on the radial Deformation amount, determine the target deformation amount, and then determine the fitting tolerance between the transmission input shaft and the motor output shaft based on the target deformation amount, solving the problem in related technologies of determining the fitting tolerance between the shafts of the three-bearing structure based on manual experience, resulting in the fitting tolerance To determine the problem of low accuracy, it is possible to determine the radial deformation amounts of the transmission input shaft and the motor output shaft under different forces when different forces are applied to the finite element model, combining different test conditions. , based on the radial deformation amount under each test condition, determine the target deformation amount, and determine the fitting tolerance between the shafts of the three-bearing structure based on the target deformation amount. While improving the accuracy of determining the fitting tolerance between the shafts, it can also improve the test accuracy and Efficiency technical effects.

On the basis of the above device, optionally, the device further includes a first update module of the finite element model. The first update module of the finite element model includes a mechanical property data determination unit and a first update unit of the finite element model.

A mechanical property data determination unit configured to determine mechanical property data corresponding to the finite element model; wherein the mechanical property data includes material property data and structural property data;

The first update unit of the finite element model is configured to update the finite element model based on the mechanical property data.

Based on the above device, optionally, the device further includes a second update module of the finite element model. The second update module of the finite element model includes a boundary condition determination unit and a second update unit of the finite element model.

a boundary condition determination unit configured to determine the first model boundary condition and the second model boundary condition corresponding to the finite element model; wherein the first model boundary condition is based on fixing the first bearing, the third The second bearing and the third bearing are determined, and the second model boundary condition is determined based on fixing the motor output shaft;

A second update unit of the finite element model is configured to update the finite element model based on the first model boundary condition and the second model boundary condition.

Based on the above device, optionally, the device further includes a force determination module.

The force determination module is configured to determine the force exerted on the finite element model; wherein the force includes bearing interference force, transmission gear meshing force and motor eccentric load, and the transmission gear meshing force is based on the The gear pitch circle diameter of the transmission input shaft, the gear transmission torque, the gear normal pressure angle and the helix angle at the gear pitch circle are determined.

Based on the above device, optionally, the radial deformation amount determination module 420 includes a first unit for determining the radial deformation amount.

The amount of radial deformation determines the first unit, which is configured to apply to the second bearing in the finite element model The bearing interference force is used to obtain the radial deformation amount of each refinement grid to be used corresponding to the shaft inner wall of the transmission input shaft at the second bearing position.

Based on the above device, optionally, the radial deformation amount determination module 420 includes a second radial deformation amount determination unit. The second radial deformation amount determination unit includes a gear meshing node determination subunit and a radial deformation amount determination subunit. The directional deformation amount determines the second subunit.

a gear mesh node determination subunit configured to determine the gear mesh node based on the gear pitch circle diameter of the transmission input shaft in the finite element model;

The second determination subunit for determining the amount of radial deformation is configured to apply the transmission gear meshing force to the gear meshing node when the bearing interference force is applied to the second bearing in the finite element model, to obtain The radial deformation amount corresponding to the shaft inner wall of the transmission input shaft at the second bearing position, and the radial deformation amount corresponding to the shaft outer wall of the motor output shaft at the second bearing position.

Based on the above device, optionally, the radial deformation amount determination module 420 includes a third unit for determining the radial deformation amount. The third unit for determining the radial deformation amount includes a motor load starting point determination subunit and The amount of radial deformation determines the third subunit.

a motor load starting point determination unit, configured to determine the motor load starting point of the motor output shaft in the finite element model;

The radial deformation amount determines the third subunit, which is configured to apply the motor eccentric load to the motor load from a point when the bearing interference force is applied to the second bearing in the finite element model to obtain the The radial deformation amount corresponding to the shaft inner wall of the transmission input shaft at the second bearing position, and the radial deformation amount corresponding to the shaft outer wall of the motor output shaft at the second bearing position.

Based on the above device, optionally, the target deformation amount determination module 430 includes a minimum radial deformation amount determination unit, a maximum radial deformation amount determination unit and a target deformation amount determination unit.

a minimum radial deformation amount determination unit configured to determine the minimum radial deformation amount of the shaft inner wall of the transmission input shaft at the second bearing position under different acting forces; and

a maximum radial deformation determination unit configured to determine the maximum radial deformation of the shaft outer wall of the motor output shaft at the second bearing position under different forces;

The target deformation amount determining unit is configured to determine the target deformation amount based on the minimum radial deformation amount and the maximum radial deformation amount.

The fit tolerance determination device provided by the embodiments of the present application can execute the fit tolerance determination method provided by any embodiment of the present application, and has functional modules and beneficial effects corresponding to the execution method.

Embodiment 4

Figure 15 is a schematic structural diagram of an electronic device that implements the fit tolerance determination method according to the embodiment of the present application. Electronic devices are intended to refer to various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices (eg, helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are examples only and are not intended to limit the implementation of the present application as described and/or claimed herein.

As shown in Figure 15, the electronic device 10 includes at least one processor 11, and a memory communicatively connected to the at least one processor 11, such as a read-only memory (Read-Only Memory, ROM) 12, a random access memory (Random Access Memory, RAM) 13, etc., in which the memory stores computer programs that can be executed by at least one processor. The processor 11 can execute various functions according to the computer program stored in the ROM 12 or the computer program loaded into the RAM 13 from the storage unit 18. Proper action and handling. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12 and the RAM 13 are connected to each other via the bus 14. An input/output (I/O) interface 15 is also connected to the bus 14 .

Multiple components in the electronic device 10 are connected to the I/O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a magnetic disk, an optical disk, etc. etc.; and communication unit 19, such as network card, modem, wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information/data with other devices through computer networks such as the Internet and/or various telecommunications networks.

Processor 11 may be a variety of general and/or special purpose processing components having processing and computing capabilities. Some examples of the processor 11 include a central processing unit (Central Processing Unit, CPU), a graphics processing unit (Graphics Processing Unit, GPU), various dedicated artificial intelligence (Artificial Intelligence, AI) computing chips, and various running machine learning models. Algorithm processor, digital signal processor (Digital Signal Process, DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the fit tolerance determination method.

In some embodiments, the fit tolerance determination method may be implemented as a computer program that is tangibly embodied in a computer-readable storage medium, such as the storage unit 18 . In some embodiments, part or all of the computer program may be loaded and/or installed onto the electronic device 10 via the ROM 12 and/or the communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the fit tolerance determination method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform the fit tolerance determination method in any other suitable manner (eg, by means of firmware).

Various implementations of the systems and techniques described above may be implemented in digital electronic circuit systems, Integrated circuit systems, Field Programmable Gate Array (FPGA), Application Specific Integrated Circuit (ASIC), Application Specific Standard Parts (ASSP), System on Chip (System on Chip) Chip, SOC), load programmable logic device (Complex Programmable Logic Device, CPLD), computer hardware, firmware, software, and/or their combination. These various embodiments may include implementation in one or more computer programs executable and/or interpreted on a programmable system including at least one programmable processor, the programmable processor The processor, which may be a special purpose or general purpose programmable processor, may receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device. An output device.

Computer programs for implementing the methods of the present application may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that the computer program, when executed by the processor, causes the functions/operations specified in the flowcharts and/or block diagrams to be implemented. A computer program may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of this application, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. Computer-readable storage media may include electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any suitable combination of the foregoing. Alternatively, the computer-readable storage medium may be a machine-readable signal medium. Machine-readable storage media may include electrical connections based on one or more wires, portable computer disks, hard drives, RAM, ROM, Erasable Programmable Read-Only Memory (EPROM or flash memory), Optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the above.

To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having a display device (eg, a cathode ray tube (CRT) or a liquid crystal display) for displaying information to the user. Display (LCD) monitor); and a keyboard and pointing device (eg, a mouse or a trackball) through which a user can provide input to the electronic device. Other kinds of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and may be provided in any form, including Acoustic input, voice input or tactile input) to receive input from the user.

The systems and techniques described herein may be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., A user's computer having a graphical user interface or web browser through which the user can interact with implementations of the systems and technologies described herein), or including such backend components, middleware components, or any combination of front-end components in a computing system. The components of the system may be interconnected by any form or medium of digital data communication (eg, a communications network). Examples of communication networks include: Local Area Network (LAN), Wide Area Network (WAN), blockchain network, and the Internet.

Computing systems may include clients and servers. Clients and servers are generally remote from each other and typically interact over a communications network. The relationship of client and server is created by computer programs running on corresponding computers and having a client-server relationship with each other. The server can be a cloud server, also known as cloud computing server or cloud host. It is a host product in the cloud computing service system to solve the problems that exist in traditional physical host and virtual private server (VPS) services. It has the disadvantages of difficult management and weak business scalability.

It should be understood that various forms of the process shown above may be used, with steps reordered, added or deleted. For example, each step described in this application can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of this application can be achieved.

Claims (10)

1. A method for determining fit tolerances, including:

   Based on the transmission input shaft, the motor output shaft, the first bearing, the second bearing and the third bearing, a finite element model is constructed, and the transmission input shaft, the motor output shaft, the first bearing, the second bearing are The contact components between the bearing and the third bearing are meshed to obtain at least one refined mesh to be used;

   Apply different forces to the finite element model to determine the radial deformation amount of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces; wherein, the radial The direction of the deformation amount is perpendicular to the bottom surface of the corresponding axis;

   Based on the radial deformation amount, determine the target deformation amount;

   Based on the target deformation amount, a fit tolerance between the transmission input shaft and the motor output shaft is determined.
2. The method of claim 1, further comprising:

   Determine mechanical property data corresponding to the finite element model; wherein the mechanical property data includes material property data and structural property data;

   The finite element model is updated based on the mechanical property data.
3. The method of claim 1, further comprising:

   Determine the first model boundary condition and the second model boundary condition corresponding to the finite element model; wherein the first model boundary condition is based on fixing the first bearing, the second bearing and the third The bearing is determined, and the second model boundary condition is determined based on fixing the motor output shaft;

   The finite element model is updated based on the first model boundary condition and the second model boundary condition.
4. According to the method of claim 1, when different forces are applied to the finite element model, it is determined that each refined grid to be used corresponding to the transmission input shaft and the motor output shaft is affected by different forces. Before lowering the radial deformation amount, the method further includes:

   Determine the forces exerted on the finite element model; wherein the forces include bearing interference forces, transmission gear meshing forces and motor eccentric loads, the transmission gear meshing forces are based on the gear pitch circle of the transmission input shaft It is determined by the diameter, gear transmission torque, gear normal pressure angle and gear pitch circle helix angle.
5. The method according to claim 4, wherein applying different forces to the finite element model determines the different effects of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft. The amount of radial deformation under force includes:

   Apply the bearing interference force to the second bearing in the finite element model to obtain the transmission The radial deformation amount of each shaft inner wall of the input shaft at the second bearing position corresponding to the refined mesh to be used.
6. The method according to claim 4, wherein applying different forces to the finite element model determines the different effects of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft. The amount of radial deformation under force includes:

   Determine gear mesh nodes based on the gear pitch circle diameter of the transmission input shaft in the finite element model;

   When the bearing interference force is applied to the second bearing in the finite element model, the transmission gear meshing force is applied to the gear meshing node to obtain the position of the transmission input shaft at the second bearing position. The radial deformation amount corresponding to the inner wall of the shaft, and the radial deformation amount corresponding to the outer shaft wall of the motor output shaft at the second bearing position.
7. The method according to claim 4, wherein applying different forces to the finite element model determines the different effects of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft. The amount of radial deformation under force includes:

   Determine the motor load starting point of the motor output shaft in the finite element model;

   When the bearing interference force is applied to the second bearing in the finite element model, the motor eccentric load is applied to the motor load from a point to obtain the position of the transmission input shaft at the second bearing position. The radial deformation amount corresponding to the inner wall of the shaft, and the radial deformation amount corresponding to the outer shaft wall of the motor output shaft at the second bearing position.
8. The method according to claim 1, wherein determining the target deformation amount based on the radial deformation amount includes:

   Determine the minimum radial deformation amount of the inner wall of the shaft inner wall of the transmission input shaft at the second bearing position under different acting forces; and

   Determine the maximum radial deformation of the shaft outer wall of the motor output shaft at the second bearing position under different forces;

   The target deformation amount is determined based on the minimum radial deformation amount and the maximum radial deformation amount.
9. A fitting tolerance determination device, including:

   The refined mesh determination module to be used is configured to construct a finite element model based on the transmission input shaft, the motor output shaft, the first bearing, the second bearing, and the third bearing, and calculate the transmission input shaft, the motor output shaft , meshing the contact components between the first bearing, the second bearing and the third bearing to obtain at least one refined mesh to be used;

   The radial deformation amount determination module is configured to apply different forces to the finite element model, and determine the radial diameter of each refined grid to be used corresponding to the transmission input shaft and the motor output shaft under different forces. The amount of radial deformation; wherein the direction of the amount of radial deformation is perpendicular to the bottom surface of the corresponding axis;

   The target deformation amount determination module is configured to determine the target deformation amount based on the radial deformation amount;

   A fitting tolerance determination module is configured to determine a fitting tolerance between the transmission input shaft and the motor output shaft based on the target deformation amount.
10. An electronic device, the electronic device includes:

    at least one processor; and

    a memory communicatively connected to the at least one processor; wherein,

    The memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor, so that the at least one processor can execute any one of claims 1-8 The method for determining fit tolerances.