Lead screw pair and lead screw pair preparation method

Abstract

The lead screw pair comprises a lead screw pair main body, a cavity is formed in the length direction of the lead screw pair main body, and a carbon fiber composite material layer used for enhancing the structural strength of the lead screw pair is arranged on the inner wall of the cavity. The preparation method of the lead screw pair comprises the steps that S1, a laying structure of the carbon fiber composite material layer is designed, and the carbon fiber composite material layer is prepared according to the laying structure; s2, a bonding layer used for fixing the carbon fiber composite material layer to the inner wall of the lead screw pair is prepared; s3, a carbon fiber composite material layer is fixed to the inner wall of the lead screw pair through a bonding layer, and an assembly is obtained; and S4, carrying out deformation test on the assembly body to judge whether the assembly body meets design requirements or not, if so, completing the preparation of the lead screw pair, and if not, returning to the step S1 to prepare the lead screw pair again. According to the lead screw pair and the preparation method of the lead screw pair, the problem that a ball screw pair is prone to thermal deformation during heating can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of screw rod pair strength enhancement, and in particular to a screw rod pair and a method for preparing the screw rod pair. Background Art

[0002] In the field of ultra-precision machining, the ball screw pair is a core component that affects the accuracy of machine tools, and its performance stability is crucial. However, during use, the ball screw pair will rub against other components, generate heat and cause temperature rise. The thermal deformation caused by this temperature rise will seriously affect the positioning and transmission accuracy of the ball screw pair.

[0003] At present, there are two main methods to reduce the degree of thermal deformation of ball screw pairs. One is to increase the lead of the ball screw pair to reduce the angular velocity and preload of the screw when it rotates, thereby reducing the heat generation; the other is to use a hollow screw and pass coolant to reduce the temperature of the screw and maintain a stable temperature change. However, although increasing the lead can reduce the temperature, it will increase the manufacturing difficulty, reduce the load-bearing capacity and efficiency, and increase the starting torque of the servo motor. Although the use of a hollow screw and coolant can reduce weight and inertia, increase speed, and reduce thermal shock, it will also reduce axial stiffness. Summary of the invention

[0004] The main purpose of the present invention is to provide a screw pair and a method for preparing the screw pair, so as to at least solve the problem that the ball screw pair is prone to thermal deformation when heated.

[0005] According to one aspect of the present invention, there is provided a screw pair, comprising:

[0006] The screw rod sub-body is provided with a cavity in the length direction of the screw rod sub-body, and the inner wall of the cavity is provided with a carbon fiber composite material layer for enhancing the structural strength of the screw rod sub-body.

[0007] Furthermore, an adhesive layer is provided between the carbon fiber composite material layer and the inner wall of the cavity, and the adhesive layer is respectively bonded to the carbon fiber composite material layer and the inner wall of the cavity.

[0008] Furthermore, the carbon fiber composite material layer includes a cylindrical epoxy resin matrix and carbon fibers arranged inside the epoxy resin matrix.

[0009] According to another aspect of the present invention, a method for preparing a screw pair is provided, which is used to prepare the screw pair, comprising:

[0010] Step S1: designing a laying structure of a carbon fiber composite material layer and preparing a carbon fiber composite material layer according to the laying structure;

[0011] Step S2: preparing an adhesive layer for fixing the carbon fiber composite material layer to the inner wall of the screw pair;

[0012] Step S3: fixing the carbon fiber composite material layer to the inner wall of the screw pair through the adhesive layer to obtain an assembly;

[0013] Step S4: Perform a deformation test on the assembly to determine whether the assembly meets the design requirements. If yes, the preparation of the screw pair is completed. If not, return to step S1 to prepare the screw pair again.

[0014] Furthermore, the step S1 comprises:

[0015] Step S11: selecting a predetermined model of carbon fiber composite material and calculating the mechanical parameters of the carbon fiber composite material in a spatial state by Jones mixing rule;

[0016] Step S12: calculating the thermal expansion coefficient of the carbon fiber composite material in a spatial state;

[0017] Step S13: inputting the mechanical parameters and the thermal expansion coefficient of the carbon fiber composite material in a spatial state into finite element analysis software to obtain an optimal layer structure of the carbon fiber composite material in a specific deformation state of the screw pair;

[0018] Step S14: performing layer laying based on the optimal layer laying structure to obtain a final carbon fiber composite material layer.

[0019] Furthermore, the step S11 includes:

[0020] Step S111: selecting a predetermined model of carbon fiber composite material according to design requirements;

[0021] Step S112: obtaining material components of the carbon fiber composite material, volume fractions of the material components, and mechanical parameters;

[0022] Step S113: combining the volume fraction and mechanical parameters of each material component, and calculating the mechanical parameters of the carbon fiber composite material in a spatial state by using the Jones mixing rule.

[0023] Furthermore, the material components of the carbon fiber composite material include carbon fiber material and matrix material, and the matrix material includes epoxy resin.

[0024] Furthermore, the mechanical parameters of the carbon fiber composite material in the space state include:

[0025] Elastic modulus E in 0° direction (fiber direction) 11 :

[0026] E 11 =E f c f +Em c m ;

[0027] Elastic modulus E in 90° direction (perpendicular to fiber direction) 12 :

[0028]

[0029] Poisson's ratio v in the 0° direction (fiber direction) 11 :

[0030] v 11 =c m v m +c f v f ;

[0031] Poisson's ratio v in the 90° direction (perpendicular to the fiber direction) 12 :

[0032]

[0033] Shear modulus in the plane G 12 :

[0034]

[0035] Where: E f represents the elastic modulus of carbon fiber material, c f represents the volume fraction of carbon fiber material, E m represents the elastic modulus of the matrix material, c m represents the volume fraction of the matrix material, v f represents the Poisson's ratio of carbon fiber material, v m represents the Poisson's ratio of the matrix material, G f Represents the shear modulus of carbon fiber material, G m represents the shear modulus of the matrix material.

[0036] Furthermore, the thermal expansion coefficient of the carbon fiber composite material in a spatial state includes:

[0037] Thermal expansion coefficient a in 0° direction (fiber direction) 11 :

[0038]

[0039] Thermal expansion coefficient a in the 90° direction (perpendicular to the fiber direction) 12 :

[0040] a 12 =c f (1+v f ) f+c m (1+v m ) m -v 12 a 11 ;

[0041] Among them: a f Indicates the thermal expansion coefficient of carbon fiber material, a m Indicates the coefficient of thermal expansion of the base material.

[0042] Furthermore, the step S4 comprises:

[0043] Step S41: determining a preset deformation amount of the assembly at a specific temperature according to design requirements;

[0044] Step S42: performing a deformation test on the assembly at a specific temperature to obtain an actual deformation amount of the assembly;

[0045] Step S43: determining the magnitude relationship between the actual deformation amount and the preset deformation amount; if the actual deformation amount is less than or equal to the preset deformation amount, the assembly meets the design requirements;

[0046] If the actual deformation amount is greater than the preset deformation amount, the assembly does not meet the design requirements, and the process returns to step S1 to re-prepare the screw pair.

[0047] In the present invention, by providing a carbon fiber composite material layer on the inner wall of the cavity of the screw pair body, the structural strength of the screw pair can be significantly improved. Carbon fiber composite materials have the characteristics of strength, high modulus and low density, and can effectively resist thermal deformation caused by temperature changes, thereby improving the stability and precision of the screw pair. The carbon fiber composite material layer has certain thermal conductivity, which helps to disperse and conduct heat inside the screw pair, thereby alleviating local overheating to a certain extent. Thermal deformation control can be achieved by adding a composite material layer on the inner wall of the cavity without significantly modifying the overall structure of the screw pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0049] Figure 1 It is a three-dimensional structural diagram of a screw rod pair disclosed in an embodiment of the present invention;

[0050] Figure 2 A partial cross-sectional view of a screw rod pair disclosed in an embodiment of the present invention;

[0051] Figure 3A schematic diagram of a single-layer structure of a carbon fiber composite material layer disclosed in an embodiment of the present invention;

[0052] Figure 4 The present invention is a flowchart of a method for preparing a screw rod pair disclosed in an embodiment of the present invention.

[0053] The above drawings include the following reference numerals:

[0054] 10. Screw rod sub-body; 11. Cavity; 111. Inner wall; 12. Carbon fiber composite material layer; 121. Carbon fiber; 122. Epoxy resin matrix. DETAILED DESCRIPTION

[0055] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0056] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0057] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0058] As mentioned in the background technology, the ball-type metal screw pair of the prior art will constantly rub against other structures when working, or the ball between the screw and the nut of the screw pair will also rub, which will generate heat and cause the temperature of the screw pair to rise. The temperature rise of the screw pair will cause thermal deformation, thereby affecting the positioning and transmission accuracy of the screw pair. In the method of using an internally hollowed-out screw pair to avoid thermal deformation of the screw pair by passing coolant, although the passing of coolant can avoid the temperature rise of the screw pair, due to the low axial stiffness of the hollowed-out structure in the middle, when thermal deformation or deformation by external force actually occurs, the deformation of the screw pair will also increase, and the problem of thermal deformation of the screw pair cannot be well solved. The screw pair and the screw preparation method of the present invention will be introduced and explained in detail in conjunction with the accompanying drawings.

[0059] See also Figure 1 to Figure 2 As shown, according to an embodiment of the present application, a screw pair is provided, including a screw pair body 10, a cavity 11 is provided in the length direction of the screw pair body, and a carbon fiber composite material layer 12 for enhancing the structural strength of the screw pair is provided on the inner wall 111 of the cavity 11. The screw pair of this embodiment includes a ball screw pair, and the carbon fiber composite material has a high axial tensile modulus and relatively low thermal expansion performance, which can suppress the thermal deformation of the ball screw pair, reduce the thermal deformation of the ball screw pair, and improve the structural stability of the ball screw pair.

[0060] Furthermore, an adhesive layer is provided between the carbon fiber composite material layer 12 and the inner wall 111 of the cavity 11, and the adhesive layer is respectively bonded to the carbon fiber composite material layer 12 and the inner wall 111 of the cavity 11. Optionally, the adhesive layer of this embodiment includes but is not limited to epoxy resin adhesive, which can well achieve tight bonding between the carbon fiber composite material layer 12 and the inner wall 111 of the cavity 11, and the bonding strength between the carbon fiber composite material layer 12 and the inner wall 111 of the cavity 11 is significantly improved through the adhesive layer, and the load can be evenly distributed, and stress concentration can be reduced, thereby enhancing the stability of the overall structure of the screw pair.

[0061] See also Figure 3As shown, the carbon fiber composite material layer 12 includes a cylindrical epoxy resin matrix 122 and carbon fibers 121 disposed inside the epoxy resin matrix. The carbon fiber composite material layer 12 is a multilayer structure. In each layer, the carbon fibers 121 are embedded in the epoxy resin matrix in a specific arrangement direction (such as the x direction in the figure, i.e., the carbon fiber direction), forming a carbon fiber composite material layer 12 with high strength and high rigidity. The arrangement direction of the carbon fibers in each layer of the carbon fiber composite material layer 12 is consistent. The carbon fiber composite material layer 12 is prepared by pre-impregnating carbon fibers with epoxy resin through a specific curing process. The epoxy resin matrix can protect the carbon fibers from the influence of high temperature environment. At the same time, the carbon fibers have good thermal conductivity, which helps to disperse and transfer heat, improve the thermal stability of the screw pair, and reduce the deformation of the screw pair when the temperature rises.

[0062] On the other hand, the present application also discloses a method for preparing a screw pair, which is used to prepare the above-mentioned screw pair, comprising:

[0063] Step S1: designing a laying structure of the carbon fiber composite material layer 12 and preparing the carbon fiber composite material layer 12 according to the laying structure;

[0064] Further, step S1 includes:

[0065] Step S11: selecting a predetermined model of carbon fiber composite material and calculating the mechanical parameters of the carbon fiber composite material in a spatial state by Jones mixing rule;

[0066] Step S12: calculating the thermal expansion coefficient of the carbon fiber composite material in a spatial state;

[0067] Step S13: inputting the mechanical parameters and thermal expansion coefficient of the carbon fiber composite material in a spatial state into a finite element analysis software to obtain an optimal layer structure of the carbon fiber composite material in a specific deformation state of the screw pair;

[0068] Step S14: Laminating based on the optimal layer structure to obtain the final carbon fiber composite material layer 12.

[0069] Furthermore, step S11 includes:

[0070] Step S111: selecting a predetermined model of carbon fiber composite material according to design requirements;

[0071] Step S112: obtaining material components of the carbon fiber composite material, volume fractions of the material components, and mechanical parameters;

[0072] Step S113: Combine the volume fraction and mechanical parameters of each material component and calculate the mechanical parameters of the carbon fiber composite material in the space state by Jones mixing rule. Further, the mechanical parameters of the carbon fiber composite material in the space state include:

[0073] Elastic modulus E in 0° direction (fiber direction) 11 :

[0074] E 11 =E f c f +E m c m ;

[0075] Elastic modulus E in 90° direction (perpendicular to fiber direction) 12 :

[0076]

[0077] Poisson's ratio v in the 0° direction (fiber direction) 11 :

[0078] v 11 =c m v m +c f v f ;

[0079] Poisson's ratio v in the 90° direction (perpendicular to the fiber direction) 12 :

[0080]

[0081] Shear modulus in the plane G 12 :

[0082]

[0083] Where: E f represents the elastic modulus of carbon fiber material, c f represents the volume fraction of carbon fiber material, E m represents the elastic modulus of the matrix material, c m represents the volume fraction of the matrix material, v f represents the Poisson's ratio of carbon fiber material, v m represents the Poisson's ratio of the matrix material, G f Represents the shear modulus of carbon fiber material, G m represents the shear modulus of the matrix material.

[0084] Furthermore, the thermal expansion coefficient of carbon fiber composite materials in the space state includes:

[0085] Thermal expansion coefficient a in 0° direction (fiber direction) 11 :

[0086]

[0087] Thermal expansion coefficient a in the 90° direction (perpendicular to the fiber direction) 12 :

[0088] a 12 =c f (1+v f ) f +c m (1+v m ) m -v 12 a 11 ;

[0089] Among them: a f Indicates the thermal expansion coefficient of carbon fiber material, a m Indicates the coefficient of thermal expansion of the base material.

[0090] The material components of the carbon fiber composite material include carbon fiber material and matrix material, and the matrix material includes epoxy resin.

[0091] In this embodiment, Figure 3 The x direction in the figure represents the direction of the carbon fiber, and the y direction and the z direction both represent the direction perpendicular to the carbon fiber. Assume that the volume fraction E of the carbon fiber in the predetermined carbon fiber composite material is obtained according to the experimental results. m The volume fraction of epoxy resin is 60%. m The elastic modulus of carbon fiber is 40%. f is 230GPa, the elastic modulus of epoxy resin c f is 3.5GPa, the Poisson's ratio of carbon fiber v f is 0.4, the Poisson's ratio v of epoxy resin m is 0.35, the shear modulus of carbon fiber G f is 42GPa, the shear modulus of epoxy resin G m The thermal expansion coefficient of carbon fiber is 1.2GPa. f =-0.5×10 -6 / ℃, thermal expansion coefficient of epoxy resin a m 50×10 -6 / ℃. Calculated by the above formula:

[0092] E 11 =230GPa×0.6+3.5GPa×0.4=140GPa;

[0093]

[0094] v 11 =0.4×0.6+0.35×0.4=0.38;

[0095]

[0096] a 12 =0.6×(1+0.38)×-0.5×10 -6 / ℃+0.4×(1+0.35)×50×10 -6 / ℃-0.25×12.5×10 -6 / ℃=26.2×10 -6 / ℃.

[0097] The mechanical parameters and thermal expansion coefficient obtained above are input into the finite element analysis software to simulate the deformation of the screw pair under different working conditions, and obtain the optimal layup structure of the carbon fiber composite material under the specific deformation state of the screw pair. Among them, different working conditions mean that the screw pair is subjected to different temperatures or different external forces, and the specific deformation state includes axial deformation and bending deformation. The axial deformation is the deformation along the axial direction of the screw pair, and the bending deformation is the non-axial deformation toward the screw pair. The axial deformation and bending deformation of the screw pair are minimized by simulating the optimal layup structure. Lamination is performed based on the optimal layup structure, and the final carbon fiber composite material layer 12 is prepared using a prepreg molding process.

[0098] In the above embodiment, the performance of the carbon fiber composite material layer 12 can be accurately designed by selecting a predetermined model of carbon fiber composite material, calculating its mechanical parameters and thermal expansion coefficient in a spatial state, and using finite element analysis software to obtain the optimal layer structure. It is ensured that the carbon fiber composite material layer 12 can meet the performance requirements of the screw pair under a specific deformation state, and the reliability and stability of the overall structure are improved. In step S11, by obtaining the material components of the carbon fiber composite material, the volume fraction and mechanical parameters corresponding to each material component, and combining the Jones mixing rule for calculation, the performance matching of the carbon fiber and the matrix material in the carbon fiber composite material can be optimized, so that the carbon fiber composite material has good toughness and thermal stability while maintaining high strength and high modulus, thereby improving the integrity of the screw pair. The optimal layer structure obtained by the finite element analysis software can guide the actual laying process of the carbon fiber composite material layer 12. This laying method based on simulation results not only improves the preparation efficiency, but also ensures the accuracy and consistency of the laying, and reduces the error and waste in the preparation process. When calculating the thermal expansion coefficient of carbon fiber composite materials in a spatial state, the thermal expansion coefficients in the direction of the carbon fiber and perpendicular to the direction of the carbon fiber, as well as their mutual influence, are taken into account, which helps to more accurately predict the performance of the screw assembly in high temperature or temperature change environments, thereby ensuring its stability and reliability under various working conditions.

[0099] Step S2: preparing an adhesive layer for fixing the carbon fiber composite material layer 12 to the inner wall 111 of the screw pair.

[0100] Optionally, an epoxy resin adhesive is selected as the bonding layer material, and the formula of the epoxy resin adhesive is adjusted according to the compatibility of the carbon fiber composite material and the screw rod pair material. The epoxy resin adhesive is bonded to the inner wall 111 of the screw rod pair by coating or injection molding to form a uniform bonding layer. Using an epoxy resin adhesive made of the same material as the surface of the carbon fiber composite material layer 12 as the bonding layer material can not only improve the bonding performance, but also be used to protect the carbon fiber composite material layer 12.

[0101] Step S3: fix the carbon fiber composite material layer 12 to the inner wall 111 of the screw pair through the adhesive layer to obtain an assembly.

[0102] Optionally, the prepared carbon fiber composite material layer 12 is adhered to the adhesive layer of the inner wall 111 of the screw pair, and a hot pressing or curing process is used to tightly bond the carbon fiber composite material layer 12 to the adhesive layer and the screw pair. By forming a tight bond between the carbon fiber composite material layer 12, the adhesive layer and the screw pair, the strength of the overall structure is improved, which helps to prevent structural loosening or failure due to factors such as uneven force or temperature changes during use. Step S4: Perform a deformation test on the assembly to determine whether the assembly meets the design requirements. If so, the preparation of the screw pair is completed. If not, return to step S1 and prepare the screw pair again;

[0103] Further, step S4 includes:

[0104] Step S41: determining a preset deformation amount of the assembly at a specific temperature according to design requirements;

[0105] Step S42: performing a deformation test on the assembly at a specific temperature to obtain an actual deformation amount of the assembly;

[0106] Step S43: determining the magnitude relationship between the actual deformation variable and the preset deformation variable; if the actual deformation variable is less than or equal to the preset deformation variable, the assembly meets the design requirements;

[0107] If the actual deformation amount is greater than the preset deformation amount, the assembly does not meet the design requirements, and the process returns to step S1 to re-prepare the screw pair.

[0108] In this embodiment, assuming that the design requirement is that the maximum value of the preset deformation of the assembly at a temperature of 80°C is 0.1mm, the assembly is heated to 80°C and then subjected to a deformation test, and then the actual deformation of the assembly is measured, which can be measured using a laser rangefinder or a three-coordinate measuring instrument. The relationship between the actual deformation and the preset deformation is determined. If the actual deformation is less than or equal to 0.1mm, the assembly meets the design requirements and the preparation of the screw pair is completed. If the actual deformation is greater than 0.1mm, the assembly does not meet the design requirements, and the process returns to step S1 to reselect different types of carbon fiber composite materials and corresponding mechanical parameters to design the laying structure of the carbon fiber composite material layer 12 and prepare the screw pair.

[0109] In the above embodiment, by performing deformation test on the assembly, it is possible to accurately determine whether the deformation of the assembly at a specific temperature meets the design requirements. If the actual deformation of the assembly is greater than the preset deformation, it means that there may be problems with its structural strength or thermal stability, and it is necessary to redesign the laying structure of the carbon fiber composite material layer 12 and prepare the screw pair, ensuring that the final screw pair can maintain stable performance during long-term use, thereby improving its reliability and durability.

[0110] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0111] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0112] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A screw pair, characterized in that: include: A screw rod sub-body (10) is provided with a cavity (11) in the length direction of the screw rod sub-body (10), and an inner wall (111) of the cavity (11) is provided with a carbon fiber composite material layer (12) for enhancing the structural strength of the screw rod sub-body.

2. The screw pair according to claim 1, characterized in that: An adhesive layer is provided between the carbon fiber composite material layer (12) and the inner wall (111) of the cavity (11), and the adhesive layer is respectively bonded to the carbon fiber composite material layer (12) and the inner wall (111) of the cavity (11).

3. The screw pair according to claim 1, characterized in that: The carbon fiber composite material layer (12) comprises a cylindrical epoxy resin matrix (122) and carbon fibers (121) arranged inside the epoxy resin matrix.

4. A method for preparing a screw pair, used for preparing the screw pair according to any one of claims 1 to 3, characterized in that: include: Step S1: designing a laying structure of the carbon fiber composite material layer (12) and preparing the carbon fiber composite material layer (12) according to the laying structure; Step S2: preparing an adhesive layer for fixing the carbon fiber composite material layer (12) to the inner wall (111) of the screw rod pair; Step S3: fixing the carbon fiber composite material layer (12) to the inner wall (111) of the screw pair via the adhesive layer to obtain an assembly; Step S4: Perform a deformation test on the assembly to determine whether the assembly meets the design requirements. If yes, the preparation of the screw pair is completed. If not, return to step S1 to prepare the screw pair again.

5. The method for preparing a screw rod pair according to claim 4, characterized in that: The step S1 comprises: Step S11: selecting a predetermined model of carbon fiber composite material and calculating the mechanical parameters of the carbon fiber composite material in a spatial state by Jones mixing rule; Step S12: calculating the thermal expansion coefficient of the carbon fiber composite material in a spatial state; Step S13: inputting the mechanical parameters and the thermal expansion coefficient of the carbon fiber composite material in a spatial state into finite element analysis software to obtain an optimal layer structure of the carbon fiber composite material in a specific deformation state of the screw pair; Step S14: performing layer laying based on the optimal layer laying structure to obtain a final carbon fiber composite material layer (12).

6. The method for preparing a screw rod pair according to claim 5, characterized in that: The step S11 comprises: Step S111: selecting a predetermined model of carbon fiber composite material according to design requirements; Step S112: obtaining material components of the carbon fiber composite material, volume fractions of the material components, and mechanical parameters; Step S113: combining the volume fraction and mechanical parameters of each material component, and calculating the mechanical parameters of the carbon fiber composite material in a spatial state by using the Jones mixing rule.

7. The method for preparing a screw rod pair according to claim 6, characterized in that: The material components of the carbon fiber composite material include carbon fiber material and matrix material, and the matrix material includes epoxy resin.

8. The method for preparing a screw rod pair according to claim 7, characterized in that: The mechanical parameters of the carbon fiber composite material in the space state include: Elastic modulus E in 0° direction (fiber direction) 11 : AND 11 =And f c f +E m c m ; Elastic modulus E in 90° direction (perpendicular to fiber direction) 12 : Poisson's ratio v in the 0° direction (fiber direction) 11 : in 11 =c m in m +c f in f ; Poisson's ratio v in the 90° direction (perpendicular to the fiber direction) 12 : Shear modulus in the plane G 12 : Where: E f represents the elastic modulus of carbon fiber material, c f represents the volume fraction of carbon fiber material, E m represents the elastic modulus of the matrix material, c m represents the volume fraction of the matrix material, v f represents the Poisson's ratio of carbon fiber material, v m represents the Poisson's ratio of the matrix material, G f Represents the shear modulus of carbon fiber material, G m represents the shear modulus of the matrix material.

9. The method for preparing a screw rod pair according to claim 8, characterized in that: The thermal expansion coefficient of the carbon fiber composite material in the space state includes: Thermal expansion coefficient a in 0° direction (fiber direction) 11 : Thermal expansion coefficient a in the 90° direction (perpendicular to the fiber direction) 12 : and 12 =c f (1+v f )a f +c m (1+v m )a m -v 12 and 11 ; Among them: a f Indicates the thermal expansion coefficient of carbon fiber material, a m Indicates the thermal expansion coefficient of the base material.

10. The method for preparing a screw rod pair according to claim 4, characterized in that: The step S4 comprises: Step S41: determining a preset deformation amount of the assembly at a specific temperature according to design requirements; Step S42: performing a deformation test on the assembly at a specific temperature to obtain an actual deformation amount of the assembly; Step S43: determining the magnitude relationship between the actual deformation amount and the preset deformation amount; if the actual deformation amount is less than or equal to the preset deformation amount, the assembly meets the design requirements; If the actual deformation amount is greater than the preset deformation amount, the assembly does not meet the design requirements, and the process returns to step S1 to re-prepare the screw pair.

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