Straight gear modification design method, system, device and medium considering thermal deformation

Abstract

The application discloses a kind of straight gear modification design methods, systems, devices and medium considering thermal deformation, belong to mechanical technical field.Method includes: obtaining the basic geometric parameters, material parameters and lubrication parameters of driving gear and driven gear;Based on the obtained parameters, according to Block flash temperature theory, calculate the instantaneous flash temperature of tooth surface under the condition of considering lubrication;According to the calculated instantaneous flash temperature of tooth surface, the thermal deformation of tooth surface is calculated from the geometric analysis and temperature field theory, and the thermal deformation is considered in the calculation formula of maximum modification amount of gear;According to the maximum modification amount of gear, the straight gear modification tooth profile equation considering thermal deformation of tooth profile is constructed, and the modification tooth profile curve is obtained according to the constructed equation.The application provides a straight gear modification design calculation scheme considering thermal deformation, obtains the modification tooth profile considering thermal deformation, and helps to optimize the stability of gear system transmission.

Description

Technical Field

[0001] This invention relates to the field of mechanical technology, and in particular to a method, system, device, and medium for spur gear profile modification design that takes into account thermal deformation. Background Technology

[0002] Gear transmission systems are widely used in daily life and industrial production due to their advantages such as smooth transmission, high efficiency, and stable transmission ratio. The reliability of their transmission directly affects the performance and safety of operating equipment. The suitability of the gear tooth profile modification is a crucial factor influencing the vibration and stability of the gear system during transmission. Manufacturing errors during gear production, tooth deformation under load, and thermal deformation during transmission all affect the gear tooth profile modification. The heat generated by friction during gear transmission causes minute thermal deformation of the teeth, thus affecting the gear tooth profile modification curve and severely impacting the smoothness of the gear system's transmission. Gear transmission systems generally operate in harsh environments, and their operating temperature is affected by various factors, resulting in a non-uniform temperature field across the gear. Due to the thermal expansion and contraction properties of gear materials, the temperature field distribution of the gear leads to thermal deformation. Errors caused by thermal deformation directly affect gear transmission performance and severely impact the quality of gear modification. Therefore, studying the gear tooth profile modification equation under temperature influence is of great significance for evaluating gear transmission performance and provides guidance for gear transmission performance in actual working environments. However, corresponding technical solutions are currently lacking. Summary of the Invention

[0003] In order to at least partially solve one of the technical problems existing in the prior art, the present invention aims to provide a spur gear profile design method, system, device and medium that takes into account thermal deformation.

[0004] The technical solution adopted in this invention is:

[0005] A method for modifying spur gear profiles considering thermal deformation includes the following steps:

[0006] Obtain the basic geometric parameters, material parameters, and lubrication parameters of the driving gear and driven gear;

[0007] Based on the obtained parameters, the instantaneous flash temperature of the tooth surface is calculated considering lubrication according to the Block flash temperature theory.

[0008] Based on the calculated instantaneous flash temperature of the tooth surface, the thermal deformation of the tooth surface is calculated from the perspective of geometric analysis and temperature field theory, and the amount of thermal deformation is taken into account in the calculation formula of the maximum modification amount of the gear.

[0009] Based on the maximum modification amount of the gear, a modified tooth profile equation for spur gears considering thermal deformation of the tooth profile is constructed, and the modified tooth profile curve is obtained by solving the constructed equation.

[0010] Furthermore, the formula for calculating the instantaneous flash temperature of the tooth surface is as follows:

[0011]

[0012] v i (t)=ω i r ci (t)sin(arccos r i cosα / r ci (t))

[0013]

[0014]

[0015]

[0016] Where u is the temperature rise coefficient; f m f is the coefficient of friction; e ω represents the normal load per unit tooth width on the tooth surface; v1 and v2 are the tangential velocities on the tooth surfaces of the driving and driven gears, respectively; g1 and g2 are the thermal conductivity coefficients of the driving and driven gears, respectively; ρ1 and ρ2 are the material densities of the driving and driven gears, respectively; c1 and c2 are the specific heat capacities of the driving and driven gears, respectively; B is the half-width of the contact band; i = 1 represents the driving gear, i = 2 represents the driven gear; ω i It is the gear angular velocity; r i It is the pitch circle radius; α is the pressure angle; r ki It is the distance from the meshing point to the center of the gear; r b1 r b2 The base circle radii of the master and driven gears; r a2 R is the radius of the driven gear tooth tip circle; η is the calculation coefficient; μ is Poisson's ratio; E is the elastic modulus; F n b is the normal load on the tooth surface; b is the tooth width; R i (t) is the radius of curvature of the tooth profile at the meshing point during gear transmission, α t The pressure angle at the engagement point;

[0017] The coefficient of friction is related to the lubrication condition.

[0018] Furthermore, the lubrication states between gears include four states: dry friction, boundary lubrication, mixed lubrication, and elastohydrodynamic lubrication.

[0019] The formula for calculating the friction coefficient under mixed lubrication conditions is as follows:

[0020]

[0021] Among them, S av p represents the average tooth surface roughness.ei (t) represents the normal load per unit tooth width of the gear; η0 is the annual coefficient of lubricating oil power; sign(x) is the sign function; v e (t) represents the entrainment velocity; v s (t) represents the relative sliding velocity.

[0022] Furthermore, the calculation of tooth surface thermal deformation based on the calculated instantaneous flash temperature of the tooth surface, using geometric analysis and temperature field theory, and incorporating the thermal deformation into the calculation formula for the maximum gear modification amount, includes:

[0023] By analyzing the geometric relationship between the driving gear and the driven gear, the thermal deformation of the tooth surface is converted into the change in tooth flank clearance between the two tooth surfaces, thereby obtaining the formula for calculating the normal distance between the actual thermally deformed tooth profile and the theoretical involute tooth profile, i.e., the instantaneous tooth profile thermal deformation calculation model.

[0024] Based on gear profile modification theory, the gear dynamics model contains tooth flank clearance and time-varying meshing stiffness. Considering the instantaneous thermal deformation of the tooth profile, a calculation model for the maximum gear profile modification considering the thermal deformation of the tooth profile is constructed according to the formula for calculating the maximum gear profile modification.

[0025] Furthermore, the thermal deformation of the tooth surface is calculated in the following way:

[0026] Temperature-induced tooth profile deformation includes two parts: thermal deformation of the gear base circle and thermal deformation of the gear teeth;

[0027] The calculation formulas for base circle thermal deformation and gear tooth thermal deformation are as follows:

[0028]

[0029]

[0030]

[0031]

[0032] Δl=Δθ k r k

[0033]

[0034] Based on the geometric relationship of gear meshing, the thermal deformation of the tooth surface is converted into the change in tooth flank clearance between the two tooth surfaces, thus obtaining the formula for calculating the normal distance between the actual thermally deformed tooth profile and the theoretical involute tooth profile:

[0035]

[0036] Wherein, T(r) kT0 is the instantaneous contact temperature at the meshing point; T0 is the initial temperature of the gear; r0 is the instantaneous contact temperature at the meshing point. k α is the distance from the meshing point to the center of the gear. k α is the pressure angle at the engagement point; α is the pressure angle at the pitch circle; r b u is the diameter of the base circle; b For base circle thermal deformation; λ is the coefficient of linear expansion; μ is Poisson's ratio of the material; T(r) b ) and T(r x ) represent the temperatures of the gear base circle and the gear shaft, respectively.

[0037] Furthermore, the formula for calculating the maximum modification amount of a gear, taking into account thermal deformation, is as follows:

[0038] Δ max =Δf b +Δf+Δf m

[0039] Where, Δf b Δf is the deformation of the tooth surface under load; Δf is the thermal deformation of the tooth profile; Δf m To account for manufacturing errors in gears.

[0040] Furthermore, the construction of the spur gear profile modification equation considering thermal deformation of the tooth profile based on the maximum modification amount of the gear includes:

[0041] Based on the maximum modification amount after considering the thermal deformation of the tooth profile and the tooth profile equation before modification, the tooth profile modification equation for spur gears is derived as follows:

[0042]

[0043] Where θ is the roll angle on the base circle of the involute generating line; θ max The maximum roll angle of the involute generator; L is the shaping length; Δ max This represents the maximum amount of gear modification.

[0044] Another technical solution adopted in this invention is:

[0045] A spur gear profile modification design system considering thermal deformation includes:

[0046] The parameter acquisition module is used to acquire the basic geometric parameters, material parameters, and lubrication parameters of the driving gear and the driven gear.

[0047] The flash temperature calculation module is used to calculate the instantaneous flash temperature of the tooth surface based on the obtained parameters and according to the Block flash temperature theory, taking lubrication into account.

[0048] The deformation calculation module is used to calculate the thermal deformation of the tooth surface based on the instantaneous flash temperature of the tooth surface, starting from geometric analysis and temperature field theory, and taking the amount of thermal deformation into the calculation formula of the maximum modification amount of the gear.

[0049] The profile modification module is used to construct a spur gear profile modification equation that takes into account the thermal deformation of the tooth profile, based on the maximum profile modification amount of the gear.

[0050] Another technical solution adopted in this invention is:

[0051] A spur gear profile modification design device considering thermal deformation, comprising:

[0052] At least one processor;

[0053] At least one memory for storing at least one program;

[0054] When the at least one program is executed by the at least one processor, the at least one processor performs the method as described above.

[0055] Another technical solution adopted in this invention is:

[0056] A computer-readable storage medium storing a processor-executable program, which, when executed by a processor, performs the method described above.

[0057] The beneficial effects of this invention are: This invention provides a spur gear profile modification design calculation scheme that takes into account thermal deformation, resulting in a modified tooth profile that takes into account thermal deformation, which helps to optimize the stability of gear system transmission. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following description is provided with accompanying drawings of the relevant technical solutions in the embodiments of the present invention or the prior art. It should be understood that the accompanying drawings described below are only for the purpose of clearly illustrating some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a schematic diagram of the meshing relationship of gear transmission in an embodiment of the present invention;

[0060] Figure 2 This is a schematic diagram of the actual tooth profile deformation of the gear transmission in an embodiment of the present invention;

[0061] Figure 3 This is a schematic diagram showing the relationship between the actual deformation of the tooth profile and the thermal deformation of the tooth profile in an embodiment of the present invention;

[0062] Figure 4 This is a schematic diagram of tooth profile modification in an embodiment of the present invention;

[0063] Figure 5 This is a schematic diagram of the tooth profile modification in an embodiment of the present invention;

[0064] Figure 6 This is a flowchart illustrating the steps of a spur gear modification design method considering thermal deformation in an embodiment of the present invention. Detailed Implementation

[0065] The embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The step numbers in the following embodiments are set only for ease of explanation, and there is no limitation on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0066] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0067] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0068] Furthermore, in the description of this invention, unless otherwise stated, "multiple" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0069] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0070] like Figure 6 As shown, this embodiment provides a method for calculating the transmission error of spur gears considering thermal deformation, including the following steps:

[0071] S1. Obtain the basic geometric parameters, material parameters, and lubrication parameters of the driving gear and driven gear;

[0072] S2. Based on the obtained parameters, calculate the instantaneous flash temperature of the tooth surface according to the Block flash temperature theory, taking lubrication into account.

[0073] S3. Based on the calculated instantaneous flash temperature of the tooth surface, calculate the thermal deformation of the tooth surface from the perspective of geometric analysis and temperature field theory, and take the amount of thermal deformation into the calculation formula of the maximum modification amount of the gear.

[0074] S4. Construct a spur gear profile modification equation that considers thermal deformation of the tooth profile based on the maximum modification amount of the gear, and solve the modified tooth profile curve based on the constructed equation.

[0075] In this embodiment, firstly, based on the actual working conditions and lubrication conditions of the gears, the instantaneous contact temperature of the driving and driven gear tooth surfaces during gear transmission is calculated using the Blok flash temperature theory. Then, based on the geometric relationship of gear meshing and the connection between the basic gear parameters, and considering the thermal deformation of the gear matrix, an instantaneous tooth profile thermal deformation calculation model is constructed using temperature field theory. Next, based on the known tooth flank clearance function and time-varying meshing stiffness calculation model, the instantaneous tooth profile thermal deformation of the gear transmission is considered, and a new calculation model for the maximum gear profile modification is constructed. Finally, a spur gear profile modification equation considering thermal deformation is constructed, and the modified tooth profile curve is calculated.

[0076] Specifically, firstly, the meshing relationship between the driving and driven gears in the gear transmission process is analyzed. Based on the known basic gear parameters, the tangential velocity along the two tooth surfaces, the distance from the instantaneous meshing point to the gear center, and the contact half-width between the two tooth surfaces are calculated. Then, using the Blok flash temperature theory, the instantaneous contact temperature of the tooth surface during the gear transmission process is calculated. Based on the actual working environment of the gear system, the lubrication state of the gear transmission is analyzed, and the gear transmission friction coefficient under mixed lubrication conditions is calculated. A calculation model for the instantaneous contact temperature of the tooth surface considering mixed lubrication conditions is constructed. On this basis, the actual geometric relationship between the tooth profiles of the driving and driven gears in the gear transmission is analyzed, and the thermal deformation of the tooth surface is converted into the gear profile modification amount, resulting in a calculation model for the maximum gear profile modification amount considering the thermal deformation of the tooth profile. Finally, based on the gear profile modification theory and the basic involute tooth profile parameter equation, the spur gear profile modification equation is derived, and the profile modification curve is calculated.

[0077] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described below in conjunction with the accompanying drawings and derivation formulas.

[0078] The tooth surface contact temperature ΔB during gear transmission mainly consists of two parts: the body temperature ΔM and the instantaneous flash temperature Δf of the tooth surface: ΔB=ΔM+Δf. According to Block flash temperature theory, the instantaneous flash temperature of the tooth surface can be calculated using the following formulas as shown in formulas (1)-(4):

[0079]

[0080] v i (t)=ω i r ki (t)sin(arccos r i cosα / r ci (t)) (2)

[0081]

[0082]

[0083] Where u is the temperature rise coefficient; f m It is the coefficient of friction (which depends on different lubrication conditions); f e The normal load per unit tooth width is expressed in N / mm; v1 and v2 are the tangential velocities on the two tooth surfaces, respectively, in m / s; g1 and g2 are the thermal conductivity coefficients of the two gears, respectively, in J*s. -1 *K -1 ρ1 and ρ2 are the material densities of the two gears, respectively, in kg*m. -3 c1 and c2 are the specific heat capacities of the two gears, in J*kg. -1 *K -1 B is the half-width of the contact band, in mm; ω i It is angular velocity, with units of rad / s; r i α is the pitch circle radius, unit: mm; α is the pressure angle, unit: rad; r ci It is the distance from the meshing point to the center of the gear, in mm. Figure 1 The geometric relationship shown can be calculated to obtain r; b1 r b2 It is the base circle radius, in mm; r a2 η is the radius of the driven gear tooth tip circle, in mm; η is the calculation coefficient; μ is Poisson's ratio; E is the elastic modulus, in MPa; F n R is the normal load on the tooth surface, in N; b is the tooth width, in mm; i (t) is the radius of curvature of the tooth profile at the meshing point, in mm.

[0084] The flash temperature of the tooth surface is related to the coefficient of friction, and the magnitude of the coefficient of friction is affected by the lubrication state between the teeth. The lubrication state of the gear system can be divided into four states: dry friction, boundary lubrication, mixed lubrication, and elastohydrodynamic lubrication. Among them, mixed lubrication is a common lubrication state in gear transmission. The coefficient of friction under this state is calculated as shown in formula (5):

[0085]

[0086] Among them, S av The average tooth surface roughness is expressed in μm; p ei (t) represents the normal load per unit tooth width of the gear, in N / mm; η0 is the dynamic viscosity coefficient of the lubricating oil, in Pa*s; sign(x) is the sign function; v e (t) represents the entrainment velocity, in m / s; v s (t) represents the relative sliding speed in m / s. The formula for calculating the flash temperature of the tooth surface under mixed lubrication conditions is shown in formula (6):

[0087]

[0088] When the tooth surface temperature changes, thermal deformation occurs due to the property of thermal expansion and contraction, causing the actual tooth profile curve of the gear to not coincide with the theoretical curve, resulting in tooth profile deformation. The tooth profile deformation caused by temperature mainly consists of two parts: thermal deformation of the gear base circle and thermal deformation of the gear teeth. The calculation of the thermal deformation of the base circle is shown in formula (7), and the set of polar coordinate equations of the tooth profile considering the thermal deformation of the base circle is shown in formula (8). The gear tooth temperature field in the gear transmission process is a non-uniform steady-state temperature field, and the temperature magnitude varies with the distance from a certain point in the gear tooth to the center of the gear, as shown in formula (9). Figure 2 The geometric relationship between radial and circumferential deformation is derived to obtain the set of equations for the tooth profile considering thermal deformation, as shown in equation (10). Figure 3 The geometric relationship between the actual tooth profile and the theoretical tooth profile in the medium gear transmission process is analyzed. Since Δl is very small, it can be approximated as having a radius of r. k The included angle is Δθ k If the arc is a segment of a circle, then the formula for calculating Δl is shown in formula (11). Δθ k The size of Δf can be calculated using formula (12). Substituting formulas (8), (10), and (12) into formula (11) yields formula (13). Based on the geometric relationship between Δf and Δl, the formula for calculating Δf is shown in formula (14).

[0089]

[0090]

[0091]

[0092]

[0093] Δl=Δθ k r k (11)

[0094]

[0095]

[0096]

[0097] Where λ is the coefficient of linear expansion; μ is the Poisson's ratio of the material; T(r) b ) and T(r x α represents the temperature of the gear base circle and gear shaft, respectively, in °C; k The pressure angle at the engagement point, in rad; s k It is the tooth thickness at the meshing point of the gear teeth, in mm; T i The radial distance is r i Tooth surface temperature, unit: °C; T a Temperature at the tooth tip, unit: °C; r x The shaft diameter is in mm; r a T(r) represents the radial distance from the tooth tip, in mm. k T0 is the instantaneous contact temperature at the meshing point, in °C; T0 is the initial temperature of the gear, in °C; s is the tooth thickness at the pitch circle, in mm; r is the pitch circle radius, in mm.

[0098] Thermal deformation caused by friction on the tooth surfaces reduces the clearance between the two tooth surfaces, affecting the amount of gear modification. According to... Figure 4 The formula for calculating the maximum modification amount of a gear considering the thermal deformation of the tooth profile is shown in formula (15).

[0099] Δ max =Δf b +Δf+Δf m (15)

[0100] Where, Δf b Δf represents the deformation of the tooth surface under load, in μm; Δf represents the thermal deformation of the tooth profile, in μm. m Gear manufacturing error, unit: μm.

[0101] See Figure 5 According to the gear modification theory, combined with the maximum modification amount of the gear considering the thermal deformation of the tooth profile and the basic involute tooth profile parameter equation, the gear modification tooth profile equation considering the thermal deformation of the tooth profile can be obtained as shown in formula (16):

[0102]

[0103] Where θ is the roll angle on the base circle of the involute generator line, in rad; θ max The maximum roll angle of the involute generator is expressed in rad; L is the shaping length, expressed in mm.

[0104] This embodiment also provides a spur gear profile modification design system that takes into account thermal deformation, including:

[0105] The parameter acquisition module is used to acquire the basic geometric parameters, material parameters, and lubrication parameters of the driving gear and the driven gear.

[0106] The flash temperature calculation module is used to calculate the instantaneous flash temperature of the tooth surface based on the obtained parameters and according to the Block flash temperature theory, taking lubrication into account.

[0107] The deformation calculation module is used to calculate the thermal deformation of the tooth surface based on the instantaneous flash temperature of the tooth surface, starting from geometric analysis and temperature field theory, and taking the amount of thermal deformation into the calculation formula of the maximum modification amount of the gear.

[0108] The profile modification module is used to construct a spur gear profile modification equation that takes into account the thermal deformation of the tooth profile, based on the maximum profile modification amount of the gear.

[0109] This embodiment provides a spur gear profile modification design system that considers thermal deformation. It can execute a spur gear profile modification design method that considers thermal deformation provided in the method embodiment of the present invention, and can execute any combination of the implementation steps of the method embodiment, possessing the corresponding functions and beneficial effects of the method.

[0110] This embodiment also provides a spur gear profile modification design device that takes into account thermal deformation, including:

[0111] At least one processor;

[0112] At least one memory for storing at least one program;

[0113] When the at least one program is executed by the at least one processor, the at least one processor performs the following: Figure 6 The method shown.

[0114] This embodiment provides a spur gear profile modification design device that considers thermal deformation. It can execute a spur gear profile modification design method that considers thermal deformation provided in the method embodiment of the present invention. It can execute any combination of implementation steps of the method embodiment and has the corresponding functions and beneficial effects of the method.

[0115] This application also discloses a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device can read the computer instructions from the computer-readable storage medium and execute the computer instructions, causing the computer device to perform... Figure 6 The method shown.

[0116] This embodiment also provides a storage medium storing instructions or programs that can execute the spur gear profile modification design method considering thermal deformation provided in the method embodiment of the present invention. When the instructions or programs are run, any combination of implementation steps of the method embodiment can be executed, possessing the corresponding functions and beneficial effects of the method.

[0117] In some alternative embodiments, the functions / operations mentioned in the block diagrams may not occur in the order shown in the operation diagrams. For example, depending on the functions / operations involved, two consecutively shown blocks may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order. Furthermore, the embodiments presented and described in the flowcharts of this invention are provided by way of example to provide a more comprehensive understanding of the technology. The disclosed methods are not limited to the operations and logic flows presented herein. Alternative embodiments are contemplated in which the order of various operations is altered and sub-operations described as part of a larger operation are executed independently.

[0118] Furthermore, although the invention has been described in the context of functional modules, it should be understood that, unless otherwise stated, one or more of the described functions and / or features may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in a separate physical device or software module. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the invention. Rather, given the properties, functions, and internal relationships of the various functional modules in the apparatus disclosed herein, the actual implementation of the module will be understood within the scope of conventional skill of an engineer. Therefore, those skilled in the art can implement the invention as set forth in the claims using ordinary techniques without excessive experimentation. It is also understood that the specific concepts disclosed are merely illustrative and not intended to limit the scope of the invention, which is determined by the full scope of the appended claims and their equivalents.

[0119] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0120] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0121] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0122] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0123] In the foregoing description of this specification, references to terms such as "one embodiment," "another embodiment," or "some embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0124] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

[0125] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A spur gear profile modification design method considering thermal deformation, characterized in that, Includes the following steps: Obtain the basic geometric parameters, material parameters, and lubrication parameters of the driving gear and driven gear; Based on the obtained parameters, the instantaneous flash temperature of the tooth surface is calculated considering lubrication according to the Block flash temperature theory. Based on the calculated instantaneous flash temperature of the tooth surface, the thermal deformation of the tooth surface is calculated from the perspective of geometric analysis and temperature field theory, and the amount of thermal deformation is taken into account in the calculation formula of the maximum modification amount of the gear. Construct a spur gear profile modification equation that considers thermal deformation of the tooth profile based on the maximum gear modification amount. The thermal deformation of the tooth surface is calculated in the following way: Temperature-induced tooth profile deformation includes two parts: thermal deformation of the gear base circle and thermal deformation of the gear teeth; The calculation formulas for base circle thermal deformation and gear tooth thermal deformation are as follows: Based on the geometric relationship of gear meshing, the thermal deformation of the tooth surface is converted into the change in tooth flank clearance between the two tooth surfaces, thus obtaining the formula for calculating the normal distance between the actual thermally deformed tooth profile and the theoretical involute tooth profile: in, T ( r k ( ) represents the instantaneous contact temperature at the meshing point; T 0 represents the initial temperature of the gear; r k The distance from the meshing point to the center of the gear; α k The pressure angle at the engagement point; α The pressure angle at the pitch circle; r b The base circle diameter; u b For thermal deformation of the base circle; λ It is the coefficient of linear expansion; μ It is the Poisson's ratio of the material; T ( r b )and T ( r x ) represent the temperatures of the gear base circle and the gear shaft, respectively.

2. The spur gear profile modification design method considering thermal deformation according to claim 1, characterized in that, The formula for calculating the instantaneous flash temperature of the tooth surface is: in, u This is the temperature rise coefficient; f m The coefficient of friction; f e The normal load per unit tooth width on the tooth surface; v 1, v 2 represents the tangential velocity on the tooth surfaces of the driving and driven gears, respectively; g 1, g 2 represents the thermal conductivity coefficients of the driving and driven gears, respectively; , These are the material densities of the driving and driven gears, respectively. , These are the specific heat capacities of the driving and driven gears, respectively. B The contact band width is half. i =1 indicates the driving wheel, i =2 indicates the driven wheel; ω i It is the gear angular velocity; r i It is the pitch circle radius; α It is the pressure angle; r ki It is the distance from the meshing point to the center of the gear; r b1 , r b2 The base circle radii of the master and driven gears; r a2 The radius of the driven gear tooth tip circle; η It is a calculation coefficient; μ It is Poisson's ratio; E It is the elastic modulus; F n It is the normal load on the tooth surface; b It is the tooth width; R i (t) is the radius of curvature of the tooth profile at the meshing point during gear transmission; The coefficient of friction is related to the lubrication condition.

3. The spur gear profile modification design method considering thermal deformation according to claim 2, characterized in that, The lubrication states between gears include four states: dry friction, boundary lubrication, mixed lubrication, and elastohydrodynamic lubrication. The formula for calculating the friction coefficient under mixed lubrication conditions is as follows: in, S av This represents the average tooth surface roughness. p ei ( t () represents the normal load per unit tooth width of the gear; η 0 represents the annual power coefficient for lubricating oil; sign( x ) is a symbolic function; v e ( t () represents the entrainment speed; v s ( t () represents the relative sliding speed.

4. The spur gear profile modification design method considering thermal deformation according to claim 1, characterized in that, The calculation of tooth surface thermal deformation based on the instantaneous flash temperature of the tooth surface, using geometric analysis and temperature field theory, and incorporating the thermal deformation into the calculation formula for the maximum gear profile includes: By analyzing the geometric relationship between the driving gear and the driven gear, the thermal deformation of the tooth surface is converted into the change in tooth flank clearance between the two tooth surfaces, thereby obtaining the formula for calculating the normal distance between the actual thermally deformed tooth profile and the theoretical involute tooth profile, i.e., the instantaneous tooth profile thermal deformation calculation model. Based on gear profile modification theory, the gear dynamics model contains tooth flank clearance and time-varying meshing stiffness. Considering the instantaneous thermal deformation of the tooth profile, a calculation model for the maximum gear profile modification considering the thermal deformation of the tooth profile is constructed according to the formula for calculating the maximum gear profile modification.

5. The spur gear profile modification design method considering thermal deformation according to claim 1, characterized in that, The formula for calculating the maximum modification amount of a gear, taking into account thermal deformation, is as follows: Where, Δ f b Δ represents the deformation of the tooth surface under load. f Δ represents the thermal deformation of the tooth profile. f m To account for manufacturing errors in gears.

6. The spur gear profile modification design method considering thermal deformation according to claim 1, characterized in that, The construction of the spur gear profile modification equation considering thermal deformation of the tooth profile based on the maximum gear modification amount includes: Based on the maximum modification amount after considering the thermal deformation of the tooth profile and the tooth profile equation before modification, the tooth profile modification equation for spur gears is derived as follows: in, θ The roll angle of the involute on the line load base circle; θ max This is the maximum roll angle of the involute generator line; L For the shaping length; This represents the maximum amount of gear modification.

7. A spur gear profile modification design system considering thermal deformation, for implementing the method according to any one of claims 1-6, characterized in that, include: The parameter acquisition module is used to acquire the basic geometric parameters, material parameters, and lubrication parameters of the driving gear and the driven gear. The flash temperature calculation module is used to calculate the instantaneous flash temperature of the tooth surface based on the obtained parameters and according to the Block flash temperature theory, taking lubrication into account. The deformation calculation module is used to calculate the thermal deformation of the tooth surface based on the instantaneous flash temperature of the tooth surface, starting from geometric analysis and temperature field theory, and taking the amount of thermal deformation into the calculation formula of the maximum modification amount of the gear. The profile modification module is used to construct a spur gear profile modification equation that takes into account the thermal deformation of the tooth profile, based on the maximum profile modification amount of the gear.

8. A spur gear profile modification design device considering thermal deformation, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method according to any one of claims 1-6.

9. A computer-readable storage medium storing a processor-executable program, characterized in that, The processor-executable program, when executed by the processor, is used to perform the method as described in any one of claims 1-6.

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