CN105844062B - End contact lacks the determination method of the reinforced major-minor spring endpoint power in piece root - Google Patents

Abstract

The invention relates to a method for determining the end point force of a main and auxiliary spring of an end-contact type few-plate root-reinforced type, and belongs to the technical field of suspension leaf springs. The present invention can according to the structure parameter of each sheet main spring and auxiliary spring of end contact type few sheet root reinforced main and auxiliary springs, the gap between main and auxiliary springs, modulus of elasticity, the load on the main and auxiliary springs, to each sheet of main spring and auxiliary spring The end force of each secondary spring is determined. Through examples and simulation verification, it can be seen that the determination method of the end point force of the end contact type few-plate root reinforced primary and secondary springs provided by the invention is correct, and accurate and reliable end-point forces of each plate of the main spring and secondary spring can be obtained. The design of the end-contact few-piece root-reinforced main and auxiliary springs, the composite stiffness check, and the stress-intensity check have laid an important technical foundation. Using this method can improve the design of the end-contact type few-piece root-reinforced variable-section main and auxiliary springs. Level, product quality, service life and vehicle ride comfort; at the same time, it can also reduce design and test costs and speed up product development.

Description

The Determination Method of End Point Force of Primary and Secondary Springs of End-Contacted Few-piece Root Reinforced Type

technical field

The invention relates to a vehicle suspension leaf spring, in particular to a method for determining the end point force of a main and auxiliary spring of an end-contact type with few-piece root-reinforced type.

Background technique

In order to meet the variable stiffness design requirements of the vehicle suspension under different loads, a small number of variable-section leaf springs are usually designed as the main and auxiliary springs, wherein a certain gap between the main spring and the auxiliary spring contacts is designed to ensure When the load is greater than the effective load of the auxiliary spring, the main and auxiliary springs contact and work together. Because the force of the first main spring is complicated, it not only bears the vertical load, but also bears the torsional load and the longitudinal load. Therefore, the thickness and length of the straight section at the end of the first main spring are actually designed to be larger than those of other parts. The thickness and length of the leaf main spring, that is, most of the ends are not isomorphic with a small number of variable-section main and auxiliary springs; at the same time, in order to strengthen the stress intensity of the few parabolic main and auxiliary springs, usually between the straight root section and the parabolic section Add a slanted line section, that is, adopt a root-reinforced few-piece primary and secondary spring. In addition, in order to meet the design requirements of different composite stiffnesses of the main and auxiliary springs, auxiliary springs of different lengths are usually used, that is, the contact positions of the main spring and the auxiliary spring are also different. Therefore, the main and auxiliary springs can be divided into end contact type and non-end contact type. The end contact type, wherein, under the condition of the thickness of the straight section at the root of the auxiliary spring and the number of sheets, the composite stiffness of the end contact type primary and secondary springs is greater than that of the non-end contact type. When the main and auxiliary springs work together, the mth main spring is not only subjected to the end point force, but also the supporting force of the auxiliary spring contacts, which makes the deformation and internal force calculation of the few main and auxiliary springs very complicated. The calculation of the end force of the main and auxiliary springs with few pieces is a key issue that restricts the design, stiffness calculation and stress strength check of the few main and auxiliary springs. However, due to the non-isomorphism of the straight section of the end of the main spring, the reinforced section of the oblique line at the root, the unequal length of the main and auxiliary springs, the deformation of the main and auxiliary springs, and the analysis and calculation of internal forces are very complicated. For reinforced main and auxiliary springs, the calculation method of the end force of the main and auxiliary springs has not been given before. At present, the influence of the unequal length of the main and auxiliary springs is mostly ignored, and the end point force of each main spring and auxiliary spring is directly calculated based on the stiffness of each main spring and auxiliary spring. Requirements for precise design and analytical calculation of reinforced primary and secondary springs. Therefore, it is necessary to establish an accurate and reliable method for determining the end-point force of the end-contact type few-piece root-reinforced primary and secondary springs to meet the rapid development of the vehicle industry and the requirements for accurate design and analysis of the few-piece parabolic primary and secondary springs. Improve the design level, product quality and performance of the few parabolic primary and secondary springs, ensure that the design requirements for the composite stiffness and stress strength of the primary and secondary springs are met, and improve the ride comfort of the vehicle; at the same time, reduce design and test costs and speed up product development.

Contents of the invention

Aiming at the above-mentioned defects in the prior art, the technical problem to be solved by the present invention is to provide a simple and reliable method for determining the end force of the primary and secondary springs of the end-contact type few-piece root-reinforced type, and its determination flow chart is shown in Fig. 1. Schematic diagram of half of the main and auxiliary springs of the end-contact type few-piece root reinforced type, as shown in Figure 2, including: main spring 1, root gasket 2, auxiliary spring 3, end gasket 4, main spring 1 and auxiliary spring Each sheet of 3 is composed of four sections: root straight section, oblique line section, parabolic section, and end straight section; between the main spring 1 and the auxiliary spring 3, there are root gaskets 2, and the end gaskets 4 are arranged between the straight sections of the ends of the main spring 1, and the material of the end gaskets is carbon fiber composite material to prevent frictional noise during operation. Among them, the width of the main spring 1 and the auxiliary spring 3 is b, half of the installation distance is l ₃ , the elastic modulus is E, and the length of the oblique line section is Δl; the half length of the main spring is L _M , and the root of the oblique line section of the main spring is The horizontal distance to the end point of the main spring is l _2M , the horizontal distance from the end of the oblique line section of the main spring to the end point of the main spring is l _2Mp ; the number of main reed pieces is m, and the thickness of the straight section at the root of each main spring is h _2M , the thickness of the straight section at the end of the oblique line section is h _2Mp , the thickness ratio of the oblique line section γ _M =h _2Mp /h _2M ; the straight section at the end of each main spring is not isomorphic, that is, the first main spring The thickness and length of the end straight sections are respectively greater than the thickness and length of the end straight sections of the other main leaf springs; the thickness of the end straight sections of the main leaf springs is h _1i , and the thickness ratio of the parabolic section is β _i = h _1i /h _2Mp , the length of the straight section at the end i=1,2,...,m.

The half length of the auxiliary spring is L _A , the horizontal distance from the root of the oblique section of the auxiliary spring to the end point of the auxiliary spring is l _2A , the horizontal distance from the end of the oblique line section of the auxiliary spring to the end point of the auxiliary spring is l _2Ap ; the number of auxiliary reeds is n , the thickness of the straight section at the root of each auxiliary spring is h _2A , the thickness of the end of the oblique section is h _2Ap , the thickness ratio of the oblique section γ _A = h _2Ap /h _2A ; the straight section at the end of each auxiliary spring The thickness of the parabola is h _A1j , the thickness ratio of the parabolic segment is β _Aj = h _A1j /h _2Ap , and the length of the straight segment at the end i=1,2,...,n.

Half length L _A of auxiliary spring 3 is less than half length L _M of main spring 1, the horizontal distance between auxiliary spring contact and main spring end point is l ₀ ; the main and auxiliary spring gap between main spring 1 and auxiliary spring 3 is δ, When the load is greater than the working load of the auxiliary spring, the contact of the auxiliary spring is in contact with a point in the straight section of the end of the main spring; when the ends of the main and auxiliary springs are in contact, the end points of the main spring and the auxiliary spring are not equal. In addition to the end point force, the m-piece main spring is also affected by the supporting force of the auxiliary spring contact at the contact point of the main and auxiliary springs. Given the structural parameters, modulus of elasticity, and loads on the main and auxiliary springs of each leaf spring and auxiliary spring, the end point force of each leaf main spring and auxiliary spring of the end-contact type few-leaf root-reinforced main and auxiliary spring Make sure.

In order to solve the above-mentioned technical problems, the method for determining the end point force of the end-contact type few-piece root reinforced primary and secondary springs provided by the present invention is characterized in that the following determination steps are adopted:

(1) Calculation of the end-point deformation coefficient G _x-Ei of the reinforced main spring at the root of each piece under the condition of end-point stress:

According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the oblique section of the main spring γ _M , the number of main reeds m, where the thickness ratio of the i-th parabolic section of the main spring is β _i , i=1,2,…,m , to calculate the end-point deformation coefficient G _x-Ei of each piece of main spring under the condition of end-point force, namely

(2) Calculation of the deformation coefficient G _x-DE of the contact point between the straight section of the end and the auxiliary spring of the m-th root reinforced main spring when the end point is stressed:

According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the slanted section of the main spring γ _M , the number of main reeds m, among which, the thickness ratio of the parabolic section of the mth main spring is β _m , the distance between the secondary spring contact and the main spring end The horizontal distance l ₀ is used to calculate the deformation coefficient G _x-DE of the m-th piece of main spring at the point of contact between the straight section of the end and the secondary spring under the condition of end force, that is

(3) Calculation of the end point deformation coefficient G _x-Ezm of the root reinforced main spring of the m-th piece under the condition that the contact points of the main and auxiliary springs are stressed:

According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the slanted section of the main spring γ _M , the number of main reeds m, among which, the thickness ratio of the parabolic section of the mth main spring is β _m , the distance between the secondary spring contact and the main spring end The horizontal distance l ₀ is used to calculate the end point deformation coefficient G _x-Ezm of the m-th main spring under the condition that the contact points of the main and auxiliary springs are stressed, namely

(4) Calculation of the deformation coefficient G _x-DEz of the m-th piece of main spring at the contact point between the straight end section and the auxiliary spring under the condition that the contact points of the main and auxiliary springs are stressed:

According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the slanted section of the main spring γ _M , the number of main reeds m, among which, the thickness ratio of the parabolic section of the mth main spring is β _m , the distance between the secondary spring contact and the main spring end The horizontal distance l ₀ is used to calculate the deformation coefficient G _x-DEz of the m-th piece of main spring at the contact point between the straight end and the auxiliary spring under the condition that the contact point of the main and auxiliary springs is under force, namely

(5) Calculation of the end point deformation coefficient G _x-EAj of the reinforced auxiliary spring at the root of each piece and the total end point deformation coefficient G _x-EAT of n superimposed auxiliary springs:

According to the half length L _A of the auxiliary spring reinforced at the root of the few pieces, the width b, the length Δl of the oblique line section, the elastic modulus E, the horizontal distance l _2Ap from the root of the parabolic section of the auxiliary spring to the end point of the auxiliary spring, and the root of the oblique line section of the auxiliary spring The horizontal distance l _2A to the end point of the auxiliary spring, the thickness ratio of the oblique section of the auxiliary spring γ _A , the number of auxiliary reeds n, where the thickness ratio of the jth parabolic section of the auxiliary spring is β _Aj , j=1,2,..., n, calculate the end point deformation coefficient G _x-EAj of each secondary spring, that is

According to the number n of secondary reeds and the end point deformation coefficient G _x-EAj of the reinforced secondary spring at the root of each piece, the total end point deformation coefficient G _x-EAT of n superimposed secondary springs is calculated, that is

(6) Calculation of the half stiffness of the main and auxiliary springs of the end-contact type few-leaf root-reinforced main and auxiliary springs:

Step I: Calculation of half the stiffness K _Mi of each main spring before the main and auxiliary springs contact:

According to the number of main reeds m, the thickness h _2M of the straight section at the root of each main spring, and the G _x-Ei calculated in step (1), half the stiffness of each main spring before the main and auxiliary springs contact K _Mi is calculated, that is,

Step II: Calculation of half the stiffness K _MAi of each main spring after the main and auxiliary springs are in contact:

According to the number of main reeds m, the thickness h _2M of the straight section at the root of each main spring, the thickness h _2A of the straight section at the root of each auxiliary spring, G _x-Ei calculated in step (1), step ( G _x-DE calculated in 2), G x-Ezm calculated in step (3), G x _{- DEz} calculated in step (4), and G _x-EAT calculated in step (5) , to calculate the half stiffness K _MAi of each main spring after the contact between the main and auxiliary springs, that is

Step III: Calculation of half the stiffness K _Aj of each auxiliary spring:

According to the number n of auxiliary reeds, the thickness h _2A of the straight section at the root of each auxiliary spring, and the G _x-EAj calculated in step (5), the half stiffness K _Aj of each auxiliary spring is calculated, namely

(7) Determination of the end point force of each main spring and auxiliary spring of the end-contact type few-piece root-reinforced main and auxiliary springs:

Step i: Calculation of the acting load P _K of the auxiliary spring:

According to the number of main reeds m, the thickness h _2M of the straight section of the root of each main spring, the gap between the main and secondary springs δ, and the K _Mi calculated in step I, the G _x-DE calculated in step (2), Calculate the load P _K of the auxiliary spring, that is

Step ii: Determination of the end point force P _i of each main spring:

According to the half of the load on the end-contact type few-piece root-reinforced primary and secondary springs, that is, the single-end point load P, the P _K calculated in the i step, the K Mi calculated in the I step, and the calculated K _Mi in the II step K _MAi , to determine the end point force P _i of each main spring, that is

Among them, when P≤P _K , P _i is not in contact with the main and auxiliary springs, that is, the end force of each piece of the main spring when only the main spring is active; when P>P _K /2, P _i is the main and auxiliary spring Contact, that is, the end force of each main spring when the main and auxiliary springs work together;

Step iii: Determination of the end point force P _Aj of each secondary spring:

According to the half of the load on the end-contact type few-leaf root-reinforced main and auxiliary springs, that is, the single-end point load P, the number of main reeds m, the thickness h _2M of the straight section of the root of each main spring, and the number of auxiliary reeds n, The thickness h _2A of the straight section at the root of each secondary spring, the P _K calculated in step i, the G _x-DE calculated in step (2), the G _x-DEz calculated in step (4), and G _x-EAT calculated in step (5), K _MAi calculated in step II, and K _Aj calculated in step III determine the end point force P _Aj of each secondary spring, namely

Advantages of the present invention over prior art

Since the root of the end-contact type few-piece root-reinforced main and auxiliary springs has a slanted line reinforcement section, the end straight section is not isomorphic, the length of the auxiliary spring is not equal to the length of the main spring, and the m-th piece of the main spring is subjected to the force of the end point. In addition, due to the support force of the secondary spring contacts, the deformation and internal force of the main and secondary springs are coupled, which makes the analysis and calculation of the end force of each piece of the main spring and secondary spring very complicated. Therefore, the end points have not been given before. The calculation method of the end point force of the main and auxiliary springs of the bottom-contact type few-piece root-reinforced type. According to the structural parameters of the main and auxiliary springs of the main and auxiliary springs, the gap between the main and auxiliary springs, the elastic modulus and the loads of the main and auxiliary springs of the end-contact type few-piece root-reinforced main and auxiliary springs, the end-contact type is less The terminal force of each leaf main spring and each leaf auxiliary spring of the sheet root reinforced main and auxiliary springs is accurately calculated. Through examples and ANSYS simulation verification, it can be known that using this method can obtain accurate and reliable calculation values of the end force of each main spring and auxiliary spring of the end-contact type few-piece root reinforced main and auxiliary springs, which is a small-piece parabolic main spring. Auxiliary spring design, stiffness check calculation, and stress strength check provide a reliable technical basis. Using this method can improve the design level, product quality and performance of the few-piece main and auxiliary springs, ensure that the design requirements for the composite stiffness and stress strength of the main and auxiliary springs are met, and improve the ride comfort of the vehicle; at the same time, it can also reduce design and test costs and speed up Product development speed.

Description of drawings

In order to better understand the present invention, further description will be made below in conjunction with the accompanying drawings.

Fig. 1 is a flow chart for determining the end force of the main and auxiliary springs of the end-contact type few-piece root-reinforced type;

Fig. 2 is a schematic diagram of the semi-symmetrical structure of the main and secondary springs of the end-contact type few-piece root-reinforced type;

Fig. 3 is the ANSYS deformation simulation nephogram of the 1st main spring of embodiment;

Fig. 4 is the ANSYS deformation simulation nephogram of the 2nd main spring of embodiment;

Fig. 5 is the ANSYS deformation simulation cloud diagram of a piece of auxiliary spring of the embodiment.

specific implementation plan

The present invention will be described in further detail below by way of examples.

Example: the width of a certain end-contact type few-piece root-reinforced primary and secondary springs is b = 60mm, half of the installation distance l ₃ = 55mm, the length of the oblique segment Δl = 30mm, and the modulus of elasticity E = 200GPa. The number of main reed pieces m=2, the half length of the main spring L _M =575mm, the horizontal distance from the root of the parabolic section of the main spring to the end point of the main spring l _2Mp =L _M -l ₃ -Δl=490mm, the root of the oblique section of the main spring The horizontal distance to the end point of the main spring l _2M = L _M -l ₃ = 520mm; the thickness of the straight section at the root of each piece of main spring h _2M = 11mm, the thickness of the end of the oblique section of the main spring h _2Mp = 10.23mm, the oblique section of the main spring The thickness ratio of the line segment γ _M =h _2Mp /h _2M =0.93; the thickness h ₁₁ of the straight section at the end of the first main spring =7mm, the thickness ratio of the parabolic segment of the first main spring β ₁ =h ₁₁ / h _2Mp = 0.69; the thickness h ₁₂ of the straight section at the end of the second main spring = 6 mm, and the thickness ratio of the parabolic section of the second main spring β ₂ = h ₁₂ /h _2Mp = 0.59. The number of auxiliary reeds n=1, the half length of the auxiliary spring L _A =525mm, the horizontal distance between the contact of the auxiliary spring and the end point of the main spring l ₀ =L _M -L _A =50mm, the root of the parabolic section of the auxiliary spring to the auxiliary The horizontal distance l 2Ap of the end point of the spring l _2Ap = L _A -l ₃ -Δl = 440mm, the horizontal distance l _2A = L _A -l ₃ = 470mm from the root of the oblique section of the auxiliary spring to the end point of the auxiliary spring; the thickness of the straight section at the root of the auxiliary spring h _2A ＝14mm, the end thickness h _2Ap of the oblique section of the auxiliary spring ＝13mm, the thickness ratio of the oblique section of the auxiliary spring γ _A ＝h _2Ap /h _2A ＝0.93; the thickness h _A11 of the straight section at the end of the auxiliary spring =8mm, the thickness ratio of the parabolic segment of the auxiliary spring β _A1 =h _A11 /h _2Ap =0.62; the gap between the main and auxiliary springs δ=47.91mm. In the case of half of the load on the main and auxiliary springs, that is, the single-end point load P=3040N, the end-point forces of the main and auxiliary springs of the end-contact type few-piece root-reinforced main and auxiliary springs are determined.

The determination method of the end point force of the end contact type few-piece root reinforced primary and secondary spring provided by the example of the present invention, its determination process is shown in Figure 1, and the specific determination steps are as follows:

(1) Calculation of the end-point deformation coefficient G _x-Ei of the reinforced main spring at the root of each piece under the condition of end-point force:

According to the length L _M of half of the root-reinforced main spring = 575mm, the width b = 60mm, the length of the oblique line segment Δl = 30mm, and the modulus of elasticity E = 200GPa, the horizontal distance l from the root of the parabolic segment of the main spring to the end point of the main spring _2Mp = 490mm, the horizontal distance from the root of the oblique line section of the main spring to the end point of the main spring l _2M = 520mm, the thickness ratio of the oblique line section of the main spring γ _M = 0.93, the number of main reed pieces m = 2, where the first piece of main spring The thickness ratio of the parabolic segment β ₁ = 0.69, the thickness ratio of the parabolic segment of the second main spring β ₂ = 0.59, the end point deformation coefficient G _x of the first main spring and the second main spring when the end points are stressed _-E1 and G _x-E2 are calculated separately, namely

(2) Calculation of the deformation coefficient G _x-DE at the contact point between the straight section of the end and the auxiliary spring of the mth root reinforced main spring when the end point is stressed:

According to the length L _M of half of the root-reinforced main spring = 575mm, the width b = 60mm, the length of the oblique line segment Δl = 30mm, and the modulus of elasticity E = 200GPa, the horizontal distance l from the root of the parabolic segment of the main spring to the end point of the main spring _2Mp = 490mm, the horizontal distance from the root of the oblique section of the main spring to the end of the main spring l _2M = 520mm, the thickness ratio of the oblique section of the main spring γ _M = 0.93, the number of main reeds m = 2, where the second main spring The thickness ratio of the parabola segment β ₂ =0.59, the horizontal distance between the auxiliary spring contact and the main spring end point l ₀ =50mm, the second main spring is at the contact point between the end straight section and the auxiliary spring when the end point is stressed The deformation coefficient G _x-DE is calculated, that is

(3) Calculation of the end-point deformation coefficient G _x-Ez2 of the root-reinforced main spring of the m-th piece under the condition that the contact points of the main and auxiliary springs are stressed:

According to the length L _M of half of the root-reinforced main spring = 575mm, the width b = 60mm, the length of the oblique line segment Δl = 30mm, and the modulus of elasticity E = 200GPa, the horizontal distance l from the root of the parabolic segment of the main spring to the end point of the main spring _2Mp = 490mm, the horizontal distance from the root of the oblique section of the main spring to the end of the main spring l _2M = 520mm, the thickness ratio of the oblique section of the main spring γ _M = 0.93, the number of main reeds m = 2, where the second main spring The thickness ratio of the parabola segment β ₂ =0.59, the horizontal distance between the secondary spring contact and the main spring end point l ₀ =50mm, the end point deformation coefficient G _x-Ez2 of the second main spring under the condition that the main and secondary spring contact points are stressed to calculate, that is

(4) Calculation of the deformation coefficient G _x-DEz at the point of contact between the straight end section and the auxiliary spring of the m-th root-reinforced main spring under the condition that the contact points of the main and auxiliary springs are stressed:

According to the length L _M of half of the root-reinforced main spring = 575mm, the width b = 60mm, the length of the oblique line segment Δl = 30mm, and the modulus of elasticity E = 200GPa, the horizontal distance l from the root of the parabolic segment of the main spring to the end point of the main spring _2Mp = 490mm, the horizontal distance from the root of the oblique section of the main spring to the end of the main spring l _2M = 520mm, the thickness ratio of the oblique section of the main spring γ _M = 0.93, the number of main reeds m = 2, where the second main spring Thickness ratio of the parabola segment β ₂ =0.59, horizontal distance l ₀ =50mm between the secondary spring contact and the main spring end point, the second main spring under the condition that the contact point of the main and secondary spring is under force The deformation coefficient G _x-DEz at the spring contact point is calculated, that is

(5) Calculation of the end point deformation coefficient G _x-EAj of the reinforced auxiliary spring at the root of each piece and the total end point deformation coefficient G _x-EAT of n superimposed auxiliary springs:

According to the length L A of half of the root-reinforced secondary spring L _A = 525mm, the width b = 60mm, the length of the oblique line segment Δl = 30mm, and the modulus of elasticity E = 200GPa, the horizontal distance l from the root of the parabolic segment of the secondary spring to the end point of the secondary spring _2Ap = 440mm, the horizontal distance from the root of the oblique section of the auxiliary spring to the end point of the auxiliary spring l _2A = 470mm, the thickness ratio of the oblique section of the auxiliary spring γ _A = 0.93, the number of auxiliary reeds n = 1, the parabolic section of the auxiliary spring Thickness ratio β _A1 = 0.62, calculate the end-point deformation coefficient G _x-EA1 of the secondary spring under the condition of end-point force, that is

According to the number of auxiliary reeds n=1, the end point deformation coefficient G _x-EA1 of the reinforced type auxiliary spring at the root of the sheet is calculated for the total end point deformation coefficient G _x-EAT of n superimposed auxiliary springs

(6) Calculation of the half stiffness of the main and auxiliary springs of the end-contact type few-leaf root-reinforced main and auxiliary springs:

Step I: Calculation of half the stiffness K _Mi of each main spring before the main and auxiliary springs contact:

According to the number of main reeds m=2, the thickness h _2M =11mm of the straight section at the root of each main spring, and G _x-E1 =107.53mm ⁴ /N and G _x-E2 = calculated in step (1) 113.42mm ⁴ /N, the half stiffnesses K _M1 and K _M2 of the first main spring and the second main spring before the contact of the main and auxiliary springs can be calculated respectively, namely

Step II: Calculation of half the stiffness K _MAi of each main spring after the main and auxiliary springs are in contact:

According to the number of main reeds m=2, the thickness h 2M of the straight section of the root of each main spring h _2M =11mm, the thickness h 2A of the straight section of the root of the secondary spring h _2A =14mm, the G calculated in step (1) _x-E1 = 107.53mm ⁴ /N and G _x-E2 = 113.42mm ⁴ /N, G _x-DE calculated in step (2) = 94.37mm ⁴ /N, G _x calculated in step (3) _-Ez2 = 94.37mm ⁴ /N, G _x-DEz = 79.78mm ⁴ /N calculated in step (4), and G _x-EAT = 98.36mm ⁴ /N calculated in step (5), can be used for After the primary and secondary springs contact, the half stiffnesses K _MA1 and K _MA2 of the first main spring and the second main spring are calculated respectively, namely

Step III: Calculation of half the stiffness K _Aj of each auxiliary spring:

According to the number of secondary reeds n=1, the thickness h 2A of the straight section of the root of the secondary spring h _2A =14mm, and the calculated G _x-EA1 =98.36mm ⁴ /N obtained in step (5), the root of the sheet is The half stiffness K _A1 of the reinforced auxiliary spring is calculated, that is

(7) Determination of the end point force of each main spring and auxiliary spring of the end-contact type few-piece root-reinforced main and auxiliary springs:

Step i: Calculation of the acting load P _K of the auxiliary spring:

According to the number of main reeds m=2, the thickness of the straight section at the root of each main spring h _2M =11mm, the gap between the main and secondary springs δ=47.91mm, K _M1 calculated in step I =12.38N/mm and K _M2 = 11.74N/mm, G _x-DE calculated in step (2) = 94.37mm ⁴ /N, calculate the load P _K of the auxiliary spring, namely

Step ii: Determination of the end point force P _i of each main spring:

According to the half of the load of the reinforced main and secondary springs at the root of the few pieces, that is, the single-end point load P=3040N, the number of main reeds m=2, the P _K calculated in the i step=2777N, the K _M1 calculated in the I step= 12.38N/mm and K _M2 ＝11.74N/mm, and K _MA1 ＝12.38N/mm and K _MA2 ＝30.55N/mm calculated in step II, for the first main spring and the second main spring End point forces _P1 and _P2 are determined, namely

Step iii: Determination of the end point force P _Aj of each secondary spring:

According to the half of the load on the main and auxiliary springs with reinforced roots of few pieces, that is, the single-end point load P=3040N, the number of main reeds m=2, the thickness of the straight section of the root of each main spring h _2M =11mm; the number of auxiliary reeds n=1, the thickness h _2A of the straight section at the root of the auxiliary spring is 14mm, the P _K calculated in step i=2777N, the G _x-DE calculated in step (2)=94.37mm ⁴ /N, G _x-DEz calculated in step (4) = 79.78mm ⁴ /N, and G _x-EAT calculated in step (5) = 98.36mm ⁴ /N, K _MA1 calculated in step II = 12.38 N/mm and K _MA2 ＝30.55N/mm, and K _A1 ＝27.90N/mm calculated in the III step, calculate the end point force P _A1 of this sheet auxiliary spring, namely

Using ANSYS finite element simulation software, according to the structural parameters and material property parameters of the main and auxiliary springs of the end-contact type few-piece root reinforced main and auxiliary springs, the ANSYS simulation model of the semi-symmetrical structure main and auxiliary springs is established, divided Grid, set the end point of the auxiliary spring in contact with the main spring, and impose fixed constraints on the root of the simulation model, apply a concentrated load F=PP _K /2=1651.5N on the end point of the spring, and the end contact type few-piece root reinforced main The deformation of the auxiliary spring is simulated by ANSYS, and the obtained ANSYS deformation simulation cloud diagram of the first main spring is shown in Figure 3; the ANSYS deformation simulation cloud diagram of the second main spring is shown in Figure 4; The ANSYS deformation simulation cloud diagram is shown in Figure 5, where the maximum deformation of the first main spring at the end position f _MA1 = 38.25mm, and the maximum deformation of the second main spring at the end position f _MA2 = 38.25mm , The maximum deformation f _A1 of the first auxiliary spring at the end position = 31.34mm.

It can be seen that under the same load condition, the ANSYS simulation verification value f _MA1 of the maximum deformation of the first and second main springs and the first auxiliary spring of the end-contact type few-leaf root-reinforced main and auxiliary springs is 38.25mm , f _MA2 ＝38.25mm, f _A1 ＝31.34mm, and the analytically calculated values of deformation respectively

The relative deviations are 0.58%, 0.58%, and 0.51% respectively; the results show that the method for determining the end point force of the end-contact type few-piece root-reinforced primary and secondary springs provided by the invention is correct, and the obtained main The end force of spring and auxiliary spring is accurate and reliable.

Claims (1)

1. The determination method of the end point force of the main and auxiliary springs of the end-contact type few-piece root-reinforced type, wherein the half-symmetrical structure of the end-contact type few-piece root-reinforced main spring and auxiliary spring is composed of a straight section at the root, an oblique line section, The parabolic section and the end straight section are composed of 4 sections. The end straight section of each main spring is non-isostructural, that is, the thickness and length of the end straight section of the first main spring are respectively greater than that of the other main springs. The thickness and length of the straight section at the end of the spring; the length of the auxiliary spring is less than the length of the main spring, when the load is greater than the working load of the auxiliary spring, the contact of the auxiliary spring is in contact with a certain point in the straight section of the end of the main spring; After the main and auxiliary springs are in contact, the end points of the main and auxiliary springs are not the same, and the last main spring in contact with the auxiliary spring is not only subjected to the end point force, but also the supporting force of the contact point of the auxiliary spring; Under the condition of the structural parameters, elastic modulus, primary and secondary spring clearance and primary and secondary spring bearing loads of the auxiliary spring, the end point force of each main spring and auxiliary spring of the end-contact type few-piece root-reinforced main and auxiliary spring is carried out. OK, the specific steps are as follows: (1) Calculation of the end-point deformation coefficient G _x-Ei of the reinforced main spring at the root of each piece under the condition of end-point force: According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the oblique section of the main spring γ _M , the number of main reeds m, where the thickness ratio of the i-th parabolic section of the main spring is β _i , i=1,2,…,m , to calculate the end-point deformation coefficient G _x-Ei of each piece of main spring under the condition of end-point force, namely (2) Calculation of the deformation coefficient G _x-DE of the contact point between the straight section of the end and the auxiliary spring of the m-th root reinforced main spring when the end point is stressed: According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the slanted section of the main spring γ _M , the number of main reeds m, among which, the thickness ratio of the parabolic section of the mth main spring is β _m , the distance between the secondary spring contact and the main spring end The horizontal distance l ₀ is used to calculate the deformation coefficient G _x-DE of the m-th piece of main spring at the point of contact between the straight section of the end and the secondary spring under the condition of end force, that is (3) Calculation of the end point deformation coefficient G _x-Ezm of the root reinforced main spring of the m-th piece under the condition that the contact points of the main and auxiliary springs are stressed: According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the slanted section of the main spring γ _M , the number of main reeds m, among which, the thickness ratio of the parabolic section of the mth main spring is β _m , the distance between the secondary spring contact and the main spring end The horizontal distance l ₀ is used to calculate the end point deformation coefficient G _x-Ezm of the m-th main spring under the condition that the contact points of the main and auxiliary springs are stressed, namely (4) Calculation of the deformation coefficient G _x-DEz of the m-th piece of main spring at the contact point between the straight end section and the auxiliary spring under the condition that the contact points of the main and auxiliary springs are stressed: According to the half length L _M of the main spring reinforced with few pieces of roots, the width b, the length of the slanted line section Δl, the elastic modulus E, the horizontal distance l _2Mp from the root of the parabolic section of the main spring to the end point of the main spring, and the root of the slanted line section of the main spring to The horizontal distance l _2M of the end point of the main spring, the thickness ratio of the slanted section of the main spring γ _M , the number of main reeds m, among which, the thickness ratio of the parabolic section of the mth main spring is β _m , the distance between the secondary spring contact and the main spring end The horizontal distance l ₀ is used to calculate the deformation coefficient G _x-DEz of the m-th piece of main spring at the contact point between the straight end and the auxiliary spring under the condition that the contact point of the main and auxiliary springs is under force, namely (5) Calculation of the end point deformation coefficient G _x-EAj of the reinforced auxiliary spring at the root of each piece and the total end point deformation coefficient G _x-EAT of n superimposed auxiliary springs: According to the half length L _A of the auxiliary spring reinforced at the root of the few pieces, the width b, the length Δl of the oblique line section, the elastic modulus E, the horizontal distance l _2Ap from the root of the parabolic section of the auxiliary spring to the end point of the auxiliary spring, and the root of the oblique line section of the auxiliary spring The horizontal distance l _2A to the end point of the auxiliary spring, the thickness ratio of the oblique section of the auxiliary spring γ _A , the number of auxiliary reeds n, where the thickness ratio of the jth parabolic section of the auxiliary spring is β _Aj , j=1,2,..., n, calculate the end point deformation coefficient G _x-EAj of each secondary spring, that is According to the number n of secondary reeds and the end point deformation coefficient G _x-EAj of the reinforced secondary spring at the root of each piece, the total end point deformation coefficient G _x-EAT of n superimposed secondary springs is calculated, that is (6) Calculation of the half stiffness of the main and auxiliary springs of the end-contact type few-leaf root-reinforced main and auxiliary springs: Step I: Calculation of half the stiffness K _Mi of each main spring before the main and auxiliary springs contact: According to the number of main reeds m, the thickness h _2M of the straight section at the root of each main spring, and the G _x-Ei calculated in step (1), half the stiffness of each main spring before the main and auxiliary springs contact K _Mi is calculated, that is, Step II: Calculation of half the stiffness K _MAi of each main spring after the main and auxiliary springs are in contact: According to the number of main reeds m, the thickness h _2M of the straight section at the root of each main spring, the thickness h _2A of the straight section at the root of each auxiliary spring, G _x-Ei calculated in step (1), step ( G _x-DE calculated in 2), G x-Ezm calculated in step (3), G x _{- DEz} calculated in step (4), and G _x-EAT calculated in step (5) , to calculate the half stiffness K _MAi of each main spring after the contact between the main and auxiliary springs, that is Step III: Calculation of half the stiffness K _Aj of each auxiliary spring: According to the number n of auxiliary reeds, the thickness h _2A of the straight section at the root of each auxiliary spring, and the G _x-EAj calculated in step (5), the half stiffness K _Aj of each auxiliary spring is calculated, namely (7) Determination of the end point force of each main spring and auxiliary spring of the end-contact type few-piece root-reinforced main and auxiliary springs: Step i: Calculation of the acting load P _K of the auxiliary spring: According to the number of main reeds m, the thickness h _2M of the straight section of the root of each main spring, the gap between the main and secondary springs δ, and the K _Mi calculated in step I, the G _x-DE calculated in step (2), Calculate the load P _K of the auxiliary spring, that is Step ii: Determination of the end point force P _i of each main spring: According to the half of the load on the end-contact type few-piece root-reinforced primary and secondary springs, that is, the single-end point load P, the P _K calculated in the i step, the K Mi calculated in the I step, and the calculated K _Mi in the II step K _MAi , to determine the end point force P _i of each main spring, that is Among them, when P≤P _K , P _i is not in contact with the main and auxiliary springs, that is, the end force of each piece of the main spring when only the main spring is active; when P>P _K /2, P _i is the main and auxiliary spring Contact, that is, the end force of each main spring when the main and auxiliary springs work together; Step iii: Determination of the end point force P _Aj of each secondary spring: According to the half of the load on the end-contact type few-leaf root-reinforced main and auxiliary springs, that is, the single-end point load P, the number of main reeds m, the thickness h _2M of the straight section of the root of each main spring, and the number of auxiliary reeds n, The thickness h _2A of the straight section at the root of each secondary spring, the P _K calculated in step i, the G _x-DE calculated in step (2), the G _x-DEz calculated in step (4), and G _x-EAT calculated in step (5), K _MAi calculated in step II, and K _Aj calculated in step III determine the end point force P _Aj of each secondary spring, namely