Multilayer composite ball slope reinforcing and pressurizing mechanism and design method thereof

Abstract

The invention discloses a multi-layer composite ball slope reinforcing and pressurizing mechanism and a design method thereof, and the multi-layer composite ball slope reinforcing and pressurizing mechanism comprises a rotating disc, a composite disc, a moving disc and rolling bodies; the rotating disc is connected with the power input shaft, and a first spiral groove is formed in the rotating disc; second spiral grooves are formed in the two sides of the composite disc correspondingly. The movable disc is connected with the pressed part, and a third spiral groove is formed in the movable disc; the directions of the lead angles of the first spiral groove and the second spiral groove as well as the second spiral groove and the third spiral groove are opposite; the rolling bodies are arranged between the first spiral groove and the second spiral groove and between the second spiral groove and the third spiral groove; the first spiral groove and the second spiral groove are staggered, and the second spiral groove and the third spiral groove are staggered. According to the multi-layer composite ball slope reinforcing and pressurizing mechanism, high-efficiency transmission can be maintained on the premise that enough displacement output is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile parts manufacturing, and more specifically, relates to a multi-layer composite ball ramp force-increasing and pressurizing mechanism and a design method thereof. Background Art

[0002] Unlike the traditional screw structure, the displacement output of the ball ramp structure is determined by the height difference between the starting point and the end point of the raceway. Since the raceway is set on the end surface of the mechanism disc, under the premise of a given ramp inclination angle, the displacement output of the entire device mainly depends on the distribution radius of the rolling body (i.e., the ball). If a larger distribution radius is used, although the space for displacement output can be increased, it will also lead to a decrease in force transmission efficiency, which is not ideal for applications with high thrust requirements. On the contrary, if the distribution radius of the ball is too small, it will limit the displacement output range, thereby affecting the stroke performance of the entire system. Summary of the invention

[0003] In order to solve the deficiencies and shortcomings of the prior art, the first object of the present invention is to provide a multi-layer composite ball ramp force-boosting and pressure-applying mechanism, which can maintain high-efficiency force transmission while ensuring sufficient displacement output.

[0004] The second object of the present invention is to provide a design method for a multi-layer composite ball ramp force-increasing and pressurizing mechanism.

[0005] The technical solution of the present invention to solve the above technical problems is:

[0006] A multi-layer composite ball ramp force-increasing and pressurizing mechanism comprises a rotating disk, a composite disk, a moving disk, and rolling bodies arranged between the rotating disk and the composite disk and between the composite disk and the moving disk, wherein:

[0007] The rotating disk is connected to the power input shaft, and a first spiral groove is arranged on the rotating disk; second spiral grooves are arranged on both sides of the composite disk; the moving disk is connected to the pressure-bearing member, and a third spiral groove is arranged on the moving disk; the first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove, have opposite directions of spiral lead angles; the rolling body is arranged between the first spiral groove and the second spiral groove, and between the second spiral groove and the third spiral groove;

[0008] The first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove are staggered with each other; when the distance between the rotating disk and the composite disk, as well as the distance between the composite disk and the movable disk is the smallest, the rolling body is located at the lowest point of the first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove; when the distance between the rotating disk and the composite disk, as well as the distance between the composite disk and the movable disk is the largest, the rolling body is located at the highest point of the first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove.

[0009] A preferred solution of the present invention is that the composite disks are in multiple groups, and along the rotation direction of the power input shaft, the directions of the helical lead angles of the second spiral grooves on the opposite surfaces between two adjacent groups of composite disks are opposite.

[0010] A preferred embodiment of the present invention is that: there are multiple rolling bodies, and correspondingly, the first spiral groove, the second spiral groove and the third spiral groove are all multiple groups; a constraint component for causing the multiple rolling bodies to rotate synchronously is arranged between the rotating disk and the composite disk, and between the composite disk and the movable disk, and the constraint component is a linkage plate, and the linkage plate is provided with an installation groove for installing the rolling body.

[0011] A preferred solution of the present invention is that: the rolling body is a ball; the mounting groove is a spherical groove, and the ball is mounted in the spherical groove.

[0012] A preferred embodiment of the present invention is that: the first spiral groove, the second spiral groove and the third spiral groove are all three groups, and the angle between two adjacent groups of the first spiral groove, the second spiral groove and the third spiral groove is 120 degrees; correspondingly, the balls between the first spiral groove and the second spiral groove and between the second spiral groove and the third spiral groove are also three groups.

[0013] A preferred solution of the present invention is: it also includes a limiting structure for radially limiting the composite disk, and the limiting structure is used to limit the radial movement of the composite disk.

[0014] The working principle of the multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention is:

[0015] The rotating disk in the multi-layer composite ball ramp force-boosting and pressurizing mechanism of the present invention is installed on the power input shaft, and the movable disk is connected to the pressure-bearing part; when not working, the distance between the rotating disk and the composite disk and between the composite disk and the movable disk is the smallest, and the rolling body is located at the lowest point of the first spiral groove and the second spiral groove and the second spiral groove and the third spiral groove; when the force needs to be increased, the power input shaft drives the rotating disk to rotate, and the first spiral groove on the rotating disk will cause the rolling body to roll in the first spiral groove and the second spiral groove; in this process, since the first spiral groove and the second spiral groove are staggered with each other under normal conditions, the first spiral groove and the second spiral groove will gradually overlap with the rotation of the power input shaft; in this way, the rolling body will roll in the first spiral groove and the second spiral groove Climbing motion is equivalent to saying that the rolling body moves from the lowest point to the highest point of the first spiral groove, and at the same time, the rolling body also moves along the lowest point to the highest point of the second spiral groove. Assuming that the climbing distance of the rolling body in the first spiral groove is L, the axial displacement of the composite disk is 2L, thereby driving the moving disk to move linearly. In addition, since the rolling body will also drive the composite disk to rotate when the rotating disk rotates, the rolling body between the composite disk and the moving disk also climbs in the second spiral groove and the third spiral groove, thereby driving the moving disk to move axially again. Assuming that the maximum output displacement between the rotating disk and the composite disk is X, the maximum output displacement of the multi-layer composite ball ramp force-enhancing and pressurizing mechanism of the present invention is 2X, so that high-efficiency transmission can be maintained while ensuring sufficient displacement output.

[0016] In addition, the unique configuration of the multi-layer composite ball ramp force boosting and pressurizing mechanism of the present invention not only increases the flexibility of the system, but also improves the overall force transmission efficiency, and provides an excellent solution, especially for application environments that require large thrust output but have limited space. By accurately controlling the number of layers of the composite disc and the helical angle in each layer of the composite disc, the working performance of the multi-layer composite ball ramp force boosting and pressurizing mechanism of the present invention can be further optimized to make it more adaptable to diverse working requirements.

[0017] A design method for a multi-layer composite ball ramp force-increasing and pressurizing mechanism comprises the following steps:

[0018] Step 1: Determine the design parameters of the multi-layer composite ball ramp force-increasing and pressurizing mechanism, wherein the design parameters include the number of spiral grooves, the curvature radius of the spiral grooves, the helix angle of the spiral grooves, the number of rolling bodies between two adjacent discs, the radius of the rolling bodies, and the number of discs;

[0019] Step 2: Determine the optimization goal, which includes minimizing friction loss, maximizing load-bearing capacity, minimizing weight, and maximizing fatigue life;

[0020] Step 3: Establish the objective function between each optimization objective and design parameter;

[0021] Step 4: Use the NSGA-II algorithm to build a multi-objective optimization model and optimize the design parameters to obtain the best design solution.

[0022] The preferred solution of the present invention is: in step 3, the steps of constructing the objective function of the carrying capacity are:

[0023] Step 301: Calculate the equivalent radius of curvature and equivalent elastic modulus between the rolling element and the spiral groove, where:

[0024] The equivalent radius of curvature is:

[0025]

[0026] Where: R 等效 is the equivalent radius of curvature; R 曲率 is the curvature radius of the spiral groove; r 滚动体 is the radius of the rolling element;

[0027] The equivalent elastic modulus is:

[0028]

[0029] Where: E 等效 Is the equivalent elastic modulus: E 1 is the elastic modulus of the rolling element; E 2 is the elastic modulus of the spiral groove: v 1 is the elastic modulus of the rolling element; v 2 is the elastic modulus of the spiral groove;

[0030] Step 302: Calculate the contact radius a and the maximum contact stress σ of the contact area between the rolling element and the spiral groove max ;in,

[0031] The contact radius a is:

[0032]

[0033] The maximum contact stress σ max for:

[0034]

[0035] Where: F is the load borne by a single rolling element;

[0036]

[0037] Where: F 总is the total external load, i.e., the force required to be applied by the multi-layer composite ball ramp force-increasing and pressurizing mechanism;

[0038] Step 303: Calculate the maximum allowable load F in the contact area between the rolling element and the spiral groove 允许 ;

[0039]

[0040] Where: 极限 is the ultimate contact strength of the material;

[0041] Substitute the contact radius a in step 302, that is:

[0042]

[0043] Step 304: Calculate the total load capacity C of the multi-layer composite ball ramp force-increasing and pressure-increasing mechanism 承载能力 :

[0044] C 承载能力 =N 滚动体 ·F 允许

[0045] Change F in step 303 允许 Substituting into the above formula, we get:

[0046]

[0047] Where: N 滚动体 is the number of rolling elements.

[0048] The preferred solution of the present invention is: in step 3, the steps of constructing the objective function of fatigue life are:

[0049] Step 311: Determine the contact radius a and the maximum contact stress σ max The functional relationship between them is:

[0050]

[0051] Step 312: Obtain the fatigue index m of the material through the SN curve of the material, and obtain the fatigue index m of the material through the maximum contact stress σ max And the fatigue index m of the material to obtain the fatigue life L 寿命 ;

[0052]

[0053] Where: C is the fatigue strength constant of the material.

[0054] The preferred solution of the present invention is: in step 3, the steps for constructing the objective function of friction loss are:

[0055] Step 321: Calculate the rolling friction loss L between the rolling element and the spiral groove 滚动 :

[0056]

[0057] Where: μ 滚动 is the rolling friction coefficient; v is the linear velocity of the rolling body;

[0058] Step 322: Calculate the sliding friction loss L between the rolling element and the spiral groove 滑动 :

[0059]

[0060] Where: μ 滑动 is the sliding friction coefficient; γ is the ratio of sliding speed to rolling speed;

[0061] Step 323: Calculate the lubricating oil film loss L between the rolling element and the spiral groove 润滑 :

[0062]

[0063] Wherein: η is the dynamic viscosity of the lubricating oil; v1 is a given speed, and the given speed v1 is a preset or given relative motion speed;

[0064] Step 324: Calculate the total friction loss L between the rolling element and the spiral groove 总 :

[0065] L 总 =L 滚动 +L 滑动 +L 润滑

[0066] Substituting in, we get

[0067]

[0068] The preferred solution of the present invention is: in step 3, the steps of constructing the objective function of weight are:

[0069] Step 331: Calculate the total mass W of the rolling element 滚动体 ;

[0070]

[0071] Where: ρ1 is the density of the rolling element; L 层数 is the number of disk bodies, the disk bodies include a moving disk, a composite disk and a rotating disk;

[0072] Step 332: Calculate the weight W of the disk 盘体 :

[0073] First, calculate the path length L of the spiral groove 螺旋槽 ;

[0074]

[0075] Where: 2πR 分布 is the circumferential length of the spiral groove; R 分布 h is the distribution radius of the rolling element; 提升 is the axial lifting height of the spiral groove, expressed as:

[0076] h 提升 =2πR 分布 tan(α1)

[0077] Substitute h 提升 The expression for the path length L of the spiral groove is 螺旋槽 for:

[0078]

[0079] Where: α1 is the helix angle;

[0080] Next, since the cross section of the spiral groove is semicircular, the volume V of a single spiral groove is 单螺旋槽 :

[0081]

[0082] Where: A 螺旋槽 is the cross-sectional area of ​​a single spiral groove;

[0083] Then, since the disk is a cylinder, its volume calculation needs to subtract the volume of the spiral groove:

[0084]

[0085] Where: t 盘体 is the thickness of the disk;

[0086] Step 333: Calculate the total weight of the tray:

[0087] W 盘体 =ρ 盘体 ·V 盘体 ·L 层数

[0088] Where: 盘体 is the number of disks.

[0089] The preferred solution of the present invention is: in step 4, the steps of constructing the multi-objective optimization model are:

[0090] Step S1: Set the population size, maximum evolutionary generations, crossover probability and mutation probability;

[0091] Step S2: Initialize the population;

[0092] Step S3: Calculate the objective function and perform Pareto classification on the population;

[0093] Step S4: Calculate the crowding degree of each individual at each Pareto level;

[0094] Step S5: performing selection, crossover and mutation operations;

[0095] Step S6: Generate a new population using the elite selection strategy;

[0096] Step S7, set the maximum evolutionary number Gen as the termination condition. If the maximum evolutionary number is not met, add 1 to the evolutionary number count and return to step S3 to continue running; if the maximum evolutionary number is met or the population converges, the optimization ends and the final Pareto solution set is obtained.

[0097] The preferred solution of the present invention is: in step S5, the tournament algorithm is used to compare the non-dominated level and crowding distance of individuals to determine the individuals; the simulated binary crossover algorithm is used to perform parent crossover on the selected individuals to generate new offspring; the adaptive mutation strategy is used to mutate the individuals that generate new offspring to generate new solutions.

[0098] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0099] 1. The multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention can maintain high-efficiency force transmission while ensuring sufficient displacement output.

[0100] 2. The unique configuration of the multi-layer composite ball ramp force-boosting and pressure-adding mechanism of the present invention not only increases the flexibility of the system, but also improves the overall force transmission efficiency, and provides an excellent solution, especially for application environments that require large thrust output but have limited space. By accurately controlling the number of layers of the composite disc and the helical angle in each layer of the composite disc, the working performance of the multi-layer composite ball ramp force-boosting and pressure-adding mechanism of the present invention can be further optimized to make it more adaptable to diverse work needs.

[0101] 3. The multi-layer composite ball ramp force-boosting and pressure-enhancing mechanism of the present invention overcomes the inherent contradiction between the distribution radius of the rolling body and the torque conversion efficiency, and achieves the purpose of ensuring sufficient displacement output and maintaining high-efficiency transmission by finely managing the axial space. Specifically, by carefully planning the specific parameters of the multi-layer composite ball ramp force-boosting and pressure-enhancing mechanism of the present invention, such as the helix angle, the curvature radius of the spiral groove, the rolling body radius, the number of spiral grooves, etc., the axial action distance can be effectively extended without sacrificing too much efficiency, thereby better serving those practical application scenarios that have strict requirements for thrust.

[0102] 4. The multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention not only solves the problem that a single-layer ball ramp mechanism is difficult to balance displacement and work efficiency, but also provides a new direction for the development of efficient motion conversion mechanisms in future new energy vehicles and other related fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0103] Figure 1 It is an exploded view of the multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention.

[0104] Figure 2 It is a schematic diagram of the structure of the rotating disk.

[0105] Figure 3 It is a schematic diagram of the structure of the composite disk.

[0106] Figure 4 It is a structural diagram of the mobile disk.

[0107] Figure 5 It is a schematic diagram of the structure of the linkage plate and the ball.

[0108] Figure 6 It is a simplified structural diagram of the multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention.

[0109] Figure 7 It is a simplified structural diagram of the limiting structure.

[0110] Figure 8 Schematic diagram of the ball movement between the rotating disk and the composite disk.

[0111] Fig. 9 The present invention is a design flow chart of the multi-layer composite ball ramp force-increasing and pressurizing mechanism. DETAILED DESCRIPTION

[0112] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0113] See also Figure 1-Figure 8The multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention comprises a rotating disk 1, a composite disk 2, a moving disk 3, and a rolling body 4 arranged between the rotating disk 1 and the composite disk 2 and between the composite disk 2 and the moving disk 3, wherein:

[0114] The rotating disk 1 is connected to the power input shaft 9, and a first spiral groove 101 is provided on the rotating disk 1; second spiral grooves 201 are provided on both sides of the composite disk 2; the moving disk 3 is connected to the pressure-bearing member, and a third spiral groove 301 is provided on the moving disk 3; the first spiral groove 101 and the second spiral groove 201 and the second spiral groove 201 and the third spiral groove 301 have opposite directions of spiral lead angles; the rolling body 4 is arranged between the first spiral groove 101 and the second spiral groove 201 and between the second spiral groove 201 and the third spiral groove 301;

[0115] The first spiral groove 101 and the second spiral groove 201 as well as the second spiral groove 201 and the third spiral groove 301 are staggered with each other; when the distance between the rotating disk 1 and the composite disk 2 as well as the distance between the composite disk 2 and the movable disk 3 is the smallest, the rolling body 4 is located at the lowest point 6 of the first spiral groove 101 and the second spiral groove 201 as well as the second spiral groove 201 and the third spiral groove 301; when the distance between the rotating disk 1 and the composite disk 2 as well as the distance between the composite disk 2 and the movable disk 3 is the largest, the rolling body 4 is located at the highest point 7 of the first spiral groove 101 and the second spiral groove 201 as well as the second spiral groove 201 and the third spiral groove 301.

[0116] In this embodiment, the composite disks 2 are multiple groups, and along the rotation direction of the power input shaft 9, the second spiral grooves 201 on the relative surfaces of two adjacent groups of composite disks 2 are staggered with each other, and the directions of the spiral angles are opposite; in this way, the axial action displacement can be increased by increasing the number of composite disks 2.

[0117] See also Figure 1-Figure 8 A constraint component for causing multiple rolling bodies 4 to rotate synchronously is provided between the rotating disk 1 and the compound disk 2, and between the compound disk 2 and the movable disk 3. The constraint component is a linkage plate 5, and a mounting groove for mounting the rolling body 4 is provided on the linkage plate 5; the rolling body 4 is a ball; the mounting groove is a spherical groove, and the ball is mounted in the spherical groove.

[0118] By setting the constraint component, all the balls in the same plane can be constrained to rotate synchronously. Since the balls installed in the spherical grooves can roll freely, when one of the balls rolls along the spiral groove, the linkage plate 5 can drive the remaining balls to roll synchronously in the corresponding spiral grooves, thereby ensuring that the positions of each ball in the spiral channel are the same, thereby ensuring that the output displacement and force directions are both in the axial direction of the movable disk 3, and also preventing the ball from sliding due to inconsistent positions of some balls in the spiral grooves.

[0119] See also Figure 1-Figure 8 The first spiral groove 101, the second spiral groove 201, and the third spiral groove 301 are all three groups, and the angle between two adjacent groups of the first spiral groove 101, the second spiral groove 201, and the third spiral groove 301 is 120 degrees; correspondingly, the balls between the first spiral groove 101 and the second spiral groove 201 and between the second spiral groove 201 and the third spiral groove 301 are also three groups.

[0120] See also Figure 1-Figure 8 The multi-layer composite ball ramp force-enhancing and pressurizing mechanism of the present invention also includes a limiting structure for radially limiting the composite disk 2. The limiting structure is used to limit the radial displacement of the composite disk 2. The limiting structure is a limiting shaft 8. The limiting shaft 8 is coaxial with the power input shaft 9 and is nested inside and outside, and a bearing 10 is arranged between the two. The composite disk 2 is slidably connected to the limiting shaft 8, and the rotating disk 1 is driven to rotate by the power input shaft 9, thereby driving the composite disk 2 to make axial movement on the limiting shaft 8, and also driving the composite disk 2 and the limiting shaft 8 used to install the composite disk 2 to rotate through friction transmission, thereby driving the movable disk 3 to make axial movement.

[0121] See also Figure 1-Figure 8 The working principle of the multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention is:

[0122] The rotating disk 1 in the multi-layer composite ball ramp force-enhancing and pressurizing mechanism of the present invention is installed on the power input shaft 9, and the moving disk 3 is connected to the pressure-bearing part; when not working, the distance between the rotating disk 1 and the composite disk 2 and the distance between the composite disk 2 and the moving disk 3 is the smallest, and the rolling body 4 is located at the lowest point 6 of the first spiral groove 101 and the second spiral groove 201 and the second spiral groove 201 and the third spiral groove 301; when it is necessary to increase the force, the power input shaft 9 drives the rotating disk 1 to rotate, and the first spiral groove 101 on the rotating disk 1 will cause the rolling body 4 to roll in the first spiral groove 101 and the second spiral groove 201; in this process, since the first spiral groove 101 and the second spiral groove 201 are staggered with each other under normal conditions, the first spiral groove 101 and the second spiral groove 201 will gradually overlap with the rotation of the power input shaft 9; in this way, the rolling body 4 will roll in the first spiral groove 101 and the second spiral groove 201. The climbing motion in the second spiral groove 201 is equivalent to that the rolling body 4 moves from the lowest point 6 to the highest point 7 of the first spiral groove 101, and the rolling body 4 also moves along the lowest point 6 to the highest point 7 of the second spiral groove 201. Assuming that the climbing distance of the rolling body 4 in the first spiral groove 101 is L, the axial displacement of the composite disk 2 is 2L, thereby driving the movable disk 3 to move in a straight line. In addition, when the rotating disk 1 rotates, the rolling body 4 will also drive the composite disk 2 to rotate, so that the rolling body 4 between the composite disk 2 and the movable disk 3 also climbs in the second spiral groove 201 and the third spiral groove 301, thereby driving the movable disk 3 to move axially again. Assuming that the maximum output displacement between the rotating disk 1 and the composite disk 2 is X, the maximum output displacement of the multi-layer composite ball ramp force-enhancing and pressurizing mechanism of the present invention is 2X, so that high-efficiency transmission can be maintained while ensuring sufficient displacement output.

[0123] In addition, the unique configuration of the multi-layer composite ball ramp force boosting and pressurizing mechanism of the present invention not only increases the flexibility of the system, but also improves the overall force transmission efficiency, and provides an excellent solution, especially for application environments that require large thrust output but limited space. By accurately controlling the number of layers of the composite disc 2 and the helical rise angle in each layer of the composite disc 2, the working performance of the multi-layer composite ball ramp force boosting and pressurizing mechanism of the present invention can be further optimized to make it more adaptable to diverse work needs.

[0124] See also Fig. 9 The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism of the present invention comprises the following steps:

[0125] Step 1: Determine the design parameters of the multi-layer composite ball ramp force-increasing and pressurizing mechanism;

[0126] In this embodiment, the design parameters include the number of spiral grooves, the curvature radius of the spiral grooves, the helix angle of the spiral grooves, the radius of the rolling body, and the number of disc bodies;

[0127] Step 2: Determine the optimization goal;

[0128] In this embodiment, the optimization objectives include minimizing friction loss, maximizing load-bearing capacity, minimizing weight, and maximizing fatigue life;

[0129] Step 3: Establish the objective function between each optimization objective and design parameter; specifically,

[0130] (1) The steps for constructing the objective function of carrying capacity are as follows:

[0131] Step 301: Calculate the equivalent radius of curvature and equivalent elastic modulus between the rolling element and the spiral groove, where:

[0132] The equivalent radius of curvature is:

[0133]

[0134] Where: R 等效 is the equivalent radius of curvature; R 曲率 is the curvature radius of the spiral groove; r 滚动体 is the radius of the rolling element;

[0135] The equivalent elastic modulus is:

[0136]

[0137] Where: E 等效 Is the equivalent elastic modulus: E 1 is the elastic modulus of the rolling element; E 2 is the elastic modulus of the spiral groove: v 1 is the elastic modulus of the rolling element; v 2 is the elastic modulus of the spiral groove;

[0138] Step 302: Calculate the contact radius a and the maximum contact stress σ of the contact area between the rolling element and the spiral groove max ;in,

[0139] The contact radius a is:

[0140]

[0141] The maximum contact stress σ max for:

[0142]

[0143] Where: F is the load borne by a single rolling element;

[0144]

[0145] Where: F 总 is the total external load, i.e., the force required to be applied by the multi-layer composite ball ramp force-increasing and pressurizing mechanism;

[0146] Step 303: Calculate the maximum allowable load F in the contact area between the rolling element and the spiral groove 允许 ;

[0147]

[0148] Where: 极限 is the ultimate contact strength of the material;

[0149] Substitute the contact radius a in step 302, that is:

[0150]

[0151] Step 304: Calculate the total load capacity C of the multi-layer composite ball ramp force-increasing and pressure-increasing mechanism 承载能力 :

[0152] C 承载能力 =N 滚动体 ·F 允许

[0153] Change F in step 303 允许 Substituting into the above formula, we get:

[0154]

[0155] Where: N 滚动体 is the number of rolling elements.

[0156] (2) Since the contact between the rolling element and the spiral raceway is a typical point contact model, the steps for constructing the objective function of fatigue life are as follows:

[0157] Step 311: Determine the contact radius a and the maximum contact stress σ max The functional relationship between them is:

[0158]

[0159] Step 312: Obtain the fatigue index m of the material through the SN curve (stress-life curve) of the material, and obtain the fatigue index m of the material through the maximum contact stress σ max And the fatigue index m of the material to obtain the fatigue life L 寿命 ;

[0160]

[0161] Substituting in, we get:

[0162]

[0163] Where: C is the fatigue strength constant of the material, obtained through experiments;

[0164] (3) The Coulomb friction, Hertz contact and elastic hydrodynamic lubrication (EHL) theories are integrated to introduce the effects of lubricating oil film thickness and viscosity on friction into the objective function. At the same time, the effects of rolling and sliding mixed friction are fully considered to provide more comprehensive guidance for engineering optimization. Therefore, the steps for constructing the objective function of friction loss are as follows:

[0165] Step 321: Calculate the rolling friction loss L between the rolling element and the spiral groove 滚动 :

[0166]

[0167] Where: μ 滚动 is the rolling friction coefficient; v is the linear velocity of the rolling body;

[0168] Step 322: Calculate the sliding friction loss L between the rolling element and the spiral groove 滑动 :

[0169]

[0170] Where: μ 滑动 is the sliding friction coefficient; γ is the ratio of sliding speed to rolling speed;

[0171] Step 323: Calculate the lubricating oil film loss L between the rolling element and the spiral groove 润滑 :

[0172]

[0173] Where: η is the dynamic viscosity of the lubricating oil; v1 is the given speed;

[0174] Step 324: Calculate the total friction loss L between the rolling element and the spiral groove 总 :

[0175] L 总 =L 滚动 +L 滑动 +L 润滑

[0176] Substituting in, we get

[0177]

[0178] (4) The steps for constructing the objective function of weight are:

[0179] Step 331: Calculate the total mass W of the rolling element 滚动体 ;

[0180]

[0181] Where: ρ1 is the density of the rolling element; L 层数 is the number of disk bodies, the disk bodies include a moving disk, a composite disk and a rotating disk;

[0182] Step 332: Calculate the weight W of the disk 盘体 :

[0183] First, calculate the path length L of the spiral groove 螺旋槽 ;

[0184]

[0185] Where: 2πR 分布 is the circumferential length of the spiral groove; R 分布 h is the distribution radius of the rolling element; 提升 is the axial lifting height of the spiral groove, expressed as:

[0186] h 提升 =2πR 分布 tan(α1)

[0187] Substitute h 提升 The expression for the path length L of the spiral groove is 螺旋槽 for:

[0188]

[0189] Where: α1 is the helix angle;

[0190] Next, since the cross section of the spiral groove is semicircular, the volume V of a single spiral groove is 单螺旋槽 :

[0191]

[0192] Where: A 螺旋槽 is the cross-sectional area of ​​a single spiral groove;

[0193] Then, since the disk is a cylinder, its volume calculation needs to subtract the volume of the spiral groove:

[0194]

[0195] Where: t 盘体 is the thickness of the disk;

[0196] Step 333: Calculate the total weight of the tray:

[0197] W 盘体 =ρ 盘体 ·V 盘体 ·L 层数

[0198] Where: 盘体 is the number of disks.

[0199] Step 4: Use the NSGA-II algorithm to build a multi-objective optimization model and optimize the design parameters to obtain the best design solution. The steps for building the multi-objective optimization model are as follows:

[0200] Step S1: Set the population size, maximum evolutionary generations, crossover probability and mutation probability;

[0201] Step S2: Initialize the population;

[0202] Step S3: Calculate the objective function and perform Pareto classification on the population;

[0203] Step S4: Calculate the crowding degree of each individual at each Pareto level;

[0204] Step S5: performing selection, crossover and mutation operations;

[0205] In this embodiment, the tournament algorithm is used to compare the non-dominated level and crowding distance of individuals to determine the individuals; the simulated binary crossover algorithm is used to perform parent crossover on the selected individuals to generate new offspring; the adaptive mutation strategy is used to mutate the individuals that generate the new offspring to generate new solutions;

[0206] Step S6: Generate a new population using the elite selection strategy;

[0207] Step S7, set the maximum evolutionary number Gen as the termination condition. If the maximum evolutionary number is not met, add 1 to the evolutionary number count and return to step S3 to continue running; if the maximum evolutionary number is met or the population converges, the optimization ends and the final Pareto solution set is obtained, that is, the optimal design parameters (the number of spiral grooves, the curvature radius of the spiral grooves, the helix angle of the spiral grooves, the radius of the rolling body, and the number of disk bodies).

[0208] The above is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited to the above content. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A multi-layer composite ball ramp force-increasing and pressurizing mechanism, characterized in that: It comprises a rotating disk, a composite disk, a moving disk, and rolling bodies arranged between the rotating disk and the composite disk and between the composite disk and the moving disk, wherein: The rotating disk is connected to the power input shaft, and a first spiral groove is arranged on the rotating disk; second spiral grooves are arranged on both sides of the composite disk; the moving disk is connected to the pressure-bearing member, and a third spiral groove is arranged on the moving disk; the first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove, have opposite directions of spiral lead angles; the rolling body is arranged between the first spiral groove and the second spiral groove, and between the second spiral groove and the third spiral groove; The first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove are staggered with each other; when the distance between the rotating disk and the composite disk, as well as the distance between the composite disk and the movable disk is the smallest, the rolling body is located at the lowest point of the first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove; when the distance between the rotating disk and the composite disk, as well as the distance between the composite disk and the movable disk is the largest, the rolling body is located at the highest point of the first spiral groove and the second spiral groove, as well as the second spiral groove and the third spiral groove.

2. The multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 1, characterized in that: The composite disks are in multiple groups, and along the rotation direction of the power input shaft, the directions of the helical lead angles of the second spiral grooves on the opposite surfaces of two adjacent groups of composite disks are opposite.

3. The multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 1, characterized in that: There are multiple rolling bodies, and correspondingly, the first spiral groove, the second spiral groove and the third spiral groove are all multiple groups; a constraint component for causing the multiple rolling bodies to rotate synchronously is arranged between the rotating disk and the composite disk, and between the composite disk and the movable disk, and the constraint component is a linkage plate, and the linkage plate is provided with an installation groove for installing the rolling body.

4. A design method for the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: Determine the design parameters of the multi-layer composite ball ramp force-increasing and pressurizing mechanism, wherein the design parameters include the number of spiral grooves, the curvature radius of the spiral grooves, the helix angle of the spiral grooves, the number of rolling bodies between two adjacent discs, the radius of the rolling bodies, and the number of discs; Step 2: Determine the optimization goal, which includes minimizing friction loss, maximizing load-bearing capacity, minimizing weight, and maximizing fatigue life; Step 3: Establish the objective function between each optimization objective and design parameter; Step 4: Use the NSGA-II algorithm to build a multi-objective optimization model and optimize the design parameters to obtain the best design solution.

5. The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 4 is characterized in that: In step 3, the steps for constructing the objective function of carrying capacity are: Step 301: Calculate the equivalent radius of curvature and equivalent elastic modulus between the rolling element and the spiral groove, where: The equivalent radius of curvature is: Where: R 等效 is the equivalent radius of curvature; R 曲率 is the curvature radius of the spiral groove; r 滚动体 is the radius of the rolling element; The equivalent elastic modulus is: Where: E 等效 is the equivalent elastic modulus: E1 is the elastic modulus of the rolling element; E2 is the elastic modulus of the spiral groove: v1 is the elastic modulus of the rolling element; v2 is the elastic modulus of the spiral groove; Step 302: Calculate the contact radius a and the maximum contact stress σ of the contact area between the rolling element and the spiral groove max ;in, The contact radius a is: The maximum contact stress σ max for: Where: F is the load borne by a single rolling element; Where: F 总 is the total external load, i.e., the force required to be applied by the multi-layer composite ball ramp force-increasing and pressurizing mechanism; Step 303: Calculate the maximum allowable load F in the contact area between the rolling element and the spiral groove 允许 ; Where: 极限 is the ultimate contact strength of the material; Substitute the contact radius a in step 302, that is: Step 304: Calculate the total load capacity C of the multi-layer composite ball ramp force-increasing and pressure-increasing mechanism 承载能力 : C 承载能力 =N 滚动体 ·F 允许 Change F in step 303 允许 Substituting into the above formula, we get: Where: N 滚动体 is the number of rolling elements.

6. The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 5 is characterized in that: In step 3, the steps for constructing the objective function of fatigue life are: Step 311: Determine the contact radius a and the maximum contact stress σ max The functional relationship between them is: Step 312: Obtain the fatigue index m of the material through the SN curve of the material, and obtain the fatigue index m of the material through the maximum contact stress σ max And the fatigue index m of the material to obtain the fatigue life L 寿命 ; Where: C is the fatigue strength constant of the material.

7. The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 6 is characterized in that: In step 3, the objective function of friction loss is constructed as follows: Step 321: Calculate the rolling friction loss L between the rolling element and the spiral groove 滚动 : Where: μ 滚动 is the rolling friction coefficient; v is the linear velocity of the rolling body; Step 322: Calculate the sliding friction loss L between the rolling element and the spiral groove 滑动 : Where: μ 滑动 is the sliding friction coefficient; γ is the ratio of sliding speed to rolling speed; Step 323: Calculate the lubricating oil film loss L between the rolling element and the spiral groove 润滑 : Where: η is the dynamic viscosity of the lubricating oil; v1 is the given speed; Step 324: Calculate the total friction loss L between the rolling element and the spiral groove 总 : L 总 =L 滚动 +L 滑动 +L 润滑 Substituting in, we get 8. The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 7 is characterized in that: In step 3, the objective function for weight is constructed as follows: Step 331: Calculate the total mass W of the rolling element 滚动体 ; Where: ρ1 is the density of the rolling element; L 层数 is the number of disk bodies, the disk bodies include a moving disk, a composite disk and a rotating disk; Step 332: Calculate the weight W of the disk 盘体 : First, calculate the path length L of the spiral groove 螺旋槽 ; Where: 2πR 分布 is the circumferential length of the spiral groove; R 分布 h is the distribution radius of the rolling element; 提升 is the axial lifting height of the spiral groove, expressed as: h 提升 =2πR 分布 ·tan(α1 Substitute h 提升 The expression for the path length L of the spiral groove is 螺旋槽 for: Where: α1 is the helix angle; Next, since the cross section of the spiral groove is semicircular, the volume V of a single spiral groove is 单螺旋槽 : Where: A 螺旋槽 is the cross-sectional area of ​​a single spiral groove; Then, since the disk is a cylinder, its volume calculation needs to subtract the volume of the spiral groove: Where: t 盘体 is the thickness of the disk; Step 333: Calculate the total weight of the tray: W 盘体 =ρ 盘体 ·V 盘体 ·L 层数 Where: 盘体 is the number of disks.

9. The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 8 is characterized in that: In step 4, the steps of constructing the multi-objective optimization model are: Step S1: Set the population size, maximum evolutionary generations, crossover probability and mutation probability; Step S2: Initialize the population; Step S3: Calculate the objective function and perform Pareto classification on the population; Step S4: Calculate the crowding degree of each individual at each Pareto level; Step S5: performing selection, crossover and mutation operations; Step S6: Generate a new population using the elite selection strategy; Step S7, set the maximum evolutionary number Gen as the termination condition. If the maximum evolutionary number is not met, add 1 to the evolutionary number count and return to step S3 to continue running; if the maximum evolutionary number is met or the population converges, the optimization ends and the final Pareto solution set is obtained.

10. The design method of the multi-layer composite ball ramp force-increasing and pressurizing mechanism according to claim 9, characterized in that: In step S5, the tournament algorithm is used to compare the non-dominated level and crowding distance of individuals to determine the individuals; the simulated binary crossover algorithm is used to perform parent crossover on the selected individuals to generate new offspring; the adaptive mutation strategy is used to mutate the individuals that generate new offspring to generate new solutions.

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