CN104361164A

CN104361164A - Design method for torque tube outer diameter of internal bias non-coaxial cab stabilizer bar system

Info

Publication number: CN104361164A
Application number: CN201410611751.7A
Authority: CN
Inventors: 周长城; 程正午; 张云山; 安艳; 袁光明; 曹海琳
Original assignee: Shandong University of Technology
Current assignee: Shandong University of Technology
Priority date: 2014-11-03
Filing date: 2014-11-03
Publication date: 2015-02-18
Anticipated expiration: 2034-11-03
Also published as: CN104361164B

Abstract

The invention relates to a design method for a torque tube outer diameter of an internal bias non-coaxial cab stabilizer bar system, and belongs to the technical field of cab suspension. A torque tube outer diameter design mathematic model and an analytical design method are built by using the rolling angular stiffness of and the linear stiffness of a stabilizer bar system and the relationship between the stabilizer bar structure and the radial stiffness of a rubber bushing through the radial stiffness of the rubber bushing and a loading coefficient of a torsion rubber bushing. Through example design and simulation verification, an accurate and reliable torque tube outer diameter design value can be obtained by the method; a reliable design method is provided for the design of cab suspension and the internal bias non-coaxial cab stabilizer bar system; a reliable technological base is established for development of CAD (computer aided design) software. By virtue of the method, the design levels of the cab suspension and the stabilizer bar system can be improved; the tilting and pitching motion of the cab is lowered; the driving smoothness and safety of a vehicle are improved; meanwhile, the design and testing expenses can also be lowered; the product development speed is accelerated.

Description

Design method for outer diameter of torsion tube of internal bias non-coaxial cab stabilizer bar system

Technical Field

The invention relates to a vehicle cab suspension, in particular to a design method of the outer diameter of a torsion tube of an internal offset non-coaxial cab stabilizer bar system.

Background

The inner offset non-coaxial cab stabilizer bar system is a coupling body consisting of a rigid body, an elastic body and a flexible body, although only consisting of a torsion tube, a swing arm and a rubber bushing. Because of the restriction of key problems such as the deformation analysis calculation of the rubber bushing, the mutual coupling of the torsional deformation and the bending deformation of the torsion tube, the load increment of the torsional rubber bushing and the like, a reliable analysis design method for the design of the outer diameter of the torsion tube of the internal offset non-coaxial cab stabilizer bar system is not provided all the time, and only the influence of the rubber bushing and the offset in the torsion tube on the rigidity of the stabilizer bar system can be approximately designed by using a conversion coefficient. At present, most of cab stabilizer bar diameter designs at home and abroad utilize ANSYS simulation software to perform simulation verification on the characteristics of a cab stabilizer bar system with a given structure through entity modeling, and although the method can obtain reliable simulation numerical values, the ANSYS simulation analysis can only verify the stabilizer bar with given parameters, an accurate analytic design formula cannot be provided, the analytic design cannot be realized, and the requirement of cab stabilizer bar system CAD software development cannot be met. With the rapid development of the vehicle industry and the continuous improvement of the vehicle running speed, higher requirements are put forward on the design of a cab suspension and a stabilizer bar system, and vehicle manufacturers urgently need CAD software of the cab stabilizer bar system. Therefore, an accurate and reliable design method for the outer diameter of the torsion tube of the internal bias non-coaxial cab stabilizer bar system is required to be established, the requirements of cab suspension and stabilizer bar system design are met, the design level and quality of products are improved, and the driving smoothness and safety of vehicles are improved; meanwhile, the design and test cost is reduced, and the product development speed is accelerated.

Disclosure of Invention

In view of the above-mentioned drawbacks in the prior art, the present invention provides a simple and reliable method for designing the outer diameter of a torsion tube of an internal bias non-coaxial cab stabilizer bar system, the design flowchart of which is shown in fig. 1; a schematic structural diagram of an internally biased non-coaxial cab stabilizer bar system, as shown in fig. 2; the structure schematic diagram of the rubber bushing of the stabilizer bar is shown in FIG. 3; the geometrical relationship diagram of the stabilizer bar system deformation and swing arm displacement is shown in fig. 4.

In order to solve the technical problem, the invention provides a method for designing the outer diameter of a torsion tube of a stabilizing rod system of an internal offset non-coaxial cab, which is characterized by comprising the following design steps:

(1) cab stabilizer bar system roll linear stiffness K_wsCalculation of design requirement value:

according to the design requirement value of the roll angle rigidity of a cab stabilizer bar systemSuspension distance L of stabilizer bar_cRoll line stiffness K to cab stabilizer bar system_wsIs calculated from the design requirement value of (1), i.e.

(2) Radial stiffness k of rubber bushing_xThe calculation of (2):

according to the inner circle radius r of the rubber sleeve_aOuter radius r_bLength L of_xModulus of elasticity E_xAnd poisson ratio mu_xRadial stiffness k to stabilizer bar rubber bushing_xPerform calculations, i.e.

k_{x} = \frac{1}{u (r_{b}) + y (r_{b})};

Wherein,

bessel correction function I (0, α r)_b)，K(0,αr_b)，I(1,αr_b)，K(1,αr_b)，

I(1,αr_a)，K(1,αr_a)，I(0,αr_a)，K(0,αr_a)；

(3) Load coefficient beta of torsion rubber bushing of internal offset non-coaxial cab_FThe calculation of (2):

according to the length L of the torsion tube_WPoisson's ratio mu of material, internal offset T, and swing arm length l₁Load factor beta to torsion rubber bushing_FPerform calculations, i.e.

(4) Equivalent combined linear stiffness K of rubber bushing of internal bias non-coaxial cab stabilizer bar system_xThe analytic calculation of (2):

according to the length l of the swing arm₁Inner offset T of the torsion tube, and radial rigidity k of the rubber bushing calculated in the step (2)_xAnd the load coefficient beta of the torsional rubber bushing calculated in the step (3)_FEquivalent combined linear stiffness K to rubber bushing of cab stabilizer bar system_xPerform calculations, i.e.

(5) Designing the outer diameter D of a torsion tube of an internal offset non-coaxial cab stabilizer bar system:

according to the length L of the torsion tube_wInner diameter d, inner offset T, elastic model E and Poisson's ratio mu, swing arm length l₁The design requirement value K of the roll line stiffness of the cab stabilizer bar system calculated in the step (1)_wsAnd (4) calculating the equivalent combined linear rigidity K of the rubber bushing of the cab stabilizer bar system obtained in the step (4)_xEstablishing a mathematical model of the outer diameter D of the torsion tube and designing the mathematical model, namely

(6) ANSYS simulation verification of the roll angle rigidity of the internal bias non-coaxial cab stabilizer bar system:

utilizing ANSYS finite element simulation software, establishing an ANSYS simulation model according to the design value of the outer diameter D of the torsion tube of the inner offset non-coaxial cab stabilizer bar system, other structural parameters and material characteristic parameters, dividing grids, applying a load F at the suspension position of the swing arm, performing ANSYS simulation on the deformation of the stabilizer bar system, and obtaining the deformation displacement F of the stabilizer bar system at the outermost end of the swing arm_A；

Deformation displacement f of stabilizer bar system at outermost end of swing arm obtained according to ANSYS simulation_ALength of swing arm l₁Distance Deltal from suspension position of swing arm to outermost end₁Suspension distance L of stabilizer bar_cA load F applied at a suspension position of the swing arm, and the rubber calculated in the step (2)Bushing radial stiffness k_xAnd the rigidity of the roll angle of the stabilizer bar system in the internally biased non-coaxial cab is realized by utilizing the geometrical relationship between the deformation of the stabilizer bar system and the displacement of the swing armThe ANSYS simulation verification value is calculated, namely

f_ws＝f_C+F/k_x；

K_{ws} = \frac{F}{f_{ws}};

ANSYS simulation verification value of inclination angle rigidity of internally-biased non-coaxial cab stabilizer bar system obtained through simulationAnd comparing the external diameter with a design required value, thereby verifying the design method and the parameter design value of the external diameter of the torsion tube of the internal offset non-coaxial cab stabilizer bar system provided by the invention.

The invention has the advantages over the prior art

Because of the restriction of key problems such as the deformation analysis calculation of the rubber bushing, the bending deformation and the torsional deformation of the torsion tube, the load increment of the torsional rubber bushing and the like, a reliable analysis design method for the design of the outer diameter of the torsion tube of the internal offset non-coaxial cab stabilizer bar system is not provided all the time, and only the influence of the deformation of the rubber bushing and the offset of the torsion tube on the rigidity of the stabilizer bar system can be approximately designed by using a certain folding coefficient within the range of 0.75-0.85. At present, ANSYS simulation software is mostly used for simulating and verifying the characteristics of a cab stabilizer bar system with a given structure at home and abroad through entity modeling, and although the method can obtain a reliable simulation numerical value, the method cannot provide an accurate analytic design formula, so that the requirement of cab stabilizer bar system CAD software development cannot be met. With the rapid development of the vehicle industry and the continuous improvement of the vehicle running speed, higher requirements are put forward on the design of a cab suspension and a stabilizer bar system, and vehicle manufacturers urgently need CAD software of the cab stabilizer bar system.

According to the invention, firstly, the relationship between the bending deformation and the torsional deformation of the torsion tube of the stabilizer bar and the load is utilized to establish the load coefficient of the torsional rubber bushing, so that the problems that the torsion tube, namely an elastic body, is coupled with the torsional rubber bushing, namely a flexible body, and the bending deformation and the torsional deformation of the torsion tube are coupled with each other are solved; then, the roll angle rigidity and linear rigidity of the cab stabilizer bar system are utilized, and the stabilizer bar structure and the radial rigidity K of the rubber bushing_xThe relation between the two is that a torsion tube outer diameter design mathematical model of an inner offset non-coaxial cab stabilizer bar system is established; therefore, the stabilizer bar system can be internally arranged according to the design requirement of the roll angle rigidity of the stabilizer bar systemAnd (4) analyzing and designing the outer diameter of a torsion tube of the offset non-coaxial cab stabilizer bar. According to the design example and ANSYS simulation verification, the method can obtain accurate and reliable design values of the outer diameter of the torsion tube, provides a reliable design method for the design of a cab suspension and stabilizer bar system, and lays a reliable technical foundation for the development of CAD software of the cab stabilizer bar system. By using the method, the design level and quality of the cab suspension and the stabilizer bar system can be improved, the design requirement of the cab suspension on the roll angle rigidity of the stabilizer bar is met, and the driving smoothness and safety of the vehicle are improved; meanwhile, the design and test cost can be reduced, and the product development speed is accelerated.

For a better understanding of the present invention, reference is made to the following further description taken in conjunction with the accompanying drawings.

FIG. 1 is a flow chart of a design of the outer diameter of a torsion tube for an internally biased non-coaxial cab stabilizer bar system;

FIG. 2 is a schematic diagram of the construction of an internally biased non-coaxial cab stabilizer bar system;

FIG. 3 is a schematic view of the construction of a rubber bushing;

FIG. 4 is a geometric relationship diagram of the deformation of the internally biased non-coaxial stabilizer bar system and the displacement of the swing arm;

FIG. 5 shows the roll stiffness of the stabilizer bar system of the first embodimentA change curve along with the outer diameter D of the torsion tube;

FIG. 6 is a simulated cloud of deformation for the internally biased non-coaxial cab stabilizer bar system of the first embodiment;

FIG. 7 is the roll stiffness of the stabilizer bar system of the second embodimentA change curve along with the outer diameter D of the torsion tube;

fig. 8 is a simulated cloud of deformation for the internally biased non-coaxial cab stabilizer bar system of the second embodiment.

Detailed description of the preferred embodiments

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

The first embodiment is as follows: the structure of a certain internally biased non-coaxial cab stabilizer bar system is bilaterally symmetrical, as shown in fig. 2, and comprises: the device comprises a swing arm 1, a suspension rubber bushing 2, a torsion rubber bushing 3 and a torsion tube 4; wherein, the torsion tube 4 is not coaxial with the torsion rubber bushing 3, and the internal offset T of the torsion tube 4 is 30 mm; distance L between two left and right swing arms 1_c1550mm, the suspension distance of the stabilizer bar; the distance between the suspension rubber bushing 2 and the torsion rubber bushing 3, i.e. the swing arm length l₁380 mm; distance delta l from swing arm suspension position C to outermost end A₁47.5 mm; length L of torsion tube 4_w1500mm, the elastic modulus E is 200GPa, the Poisson ratio mu is 0.3, the inner diameter D is 35mm, and the outer diameter D is a parameter to be designed; the structure and material characteristics of the left and right rubber bushings are completely the same, as shown in fig. 3, including: an inner circle sleeve 5, a rubber sleeve 6 and an outer circle sleeve 7, wherein the inner circle diameter d of the inner circle sleeve 5_x35mm and 2mm wall thickness; length L of rubber sleeve 6_x25mm, inner circle radius r_a19.5mm, outer radius r_b34.5mm, modulus of elasticity E_x7.84MPa, Poisson ratio mu_x0.47. Roll angle stiffness required by cab stabilizer bar designThe outer diameter D of the torsion tube of the inner offset non-coaxial cab stabilizer bar system is designed, and the roll angle rigidity under the load F-5000N is verified and ANSYS is verified.

The design method of the outer diameter of the torsion tube of the internally-biased non-coaxial cab stabilizer bar system provided by the embodiment of the invention has the calculation flow shown in figure 1, and comprises the following specific steps:

according to the design requirement value of the roll angle rigidity of a cab stabilizer bar systemSuspension distance L of stabilizer bar_c1550mm, roll line stiffness K for cab stabilizer bar system_wsIs calculated from the design requirement value of (1), i.e.

(2) Radial stiffness k of rubber bushing_xThe calculation of (2):

according to the inner circle radius r of the rubber sleeve_a19.5mm, outer radius r_b34.5mm, length L_x25mm, modulus of elasticity E_x7.84MPa and Poisson ratio mu_x0.47, radial stiffness K to the cab stabilizer rubber bushing_xPerform calculations, i.e.

Wherein,

bessel correction function I (0, α r)_b)＝5.4217×10^-3，K(0,αr_b)＝8.6369×10^-6；

I(1,αr_b)＝5.1615×10³，K(1,αr_b)＝9.0322×10^-6；

I(1,αr_a)＝63.7756，K(1,αr_a)＝0.0013，

I(0,αr_a)＝69.8524，K(0,αr_a)＝0.0012；

(3) Load factor beta of torsion rubber bushing of internal offset non-coaxial cab stabilizer bar_FThe calculation of (2):

according to the length L of the torsion tube_W1500mm, Poisson's ratio mu 0.3, 30mm internal offset T, and arm length l₁380mm, and the load coefficient beta of the torsion rubber bushing of the internally biased non-coaxial cab stabilizer bar_FPerform calculations, i.e.

according to the length l of the swing arm₁380mm, 30mm of inner offset T of the torsion tube, and k calculated in step (2)_x＝2.1113×10⁶N/m, beta calculated in step (3)_F0.1456 equivalent combined linear stiffness K of internally biased non-coaxial cab stabilizer bar system rubber bushing_xPerform calculations, i.e.

according to the length L of the torsion tube_w1500mm, 35mm inner diameter d, 200GPa elastic modulus E, 0.3 Poisson ratio mu, 30mm offset T in torsion tube, and length l of swing arm₁380mm, K calculated in step (1)_ws＝2.514×10⁵N/m, and K calculated in step (4)_x＝7.061428×10⁵N/m, establishing a torsion tube outer diameter D design mathematical model, and designing the torsion tube outer diameter D of the internally biased non-coaxial cab stabilizer bar system, namely

Wherein the roll stiffness of the cab stabilizer bar systemThe curve of the change with the outer diameter D of the torsion tube is shown in figure 5;

utilizing ANSYS finite element simulation software, establishing a simulation model according to the designed outer diameter D of the torsion tube of 50mm and other structural parameters and material characteristic parameters of the cab stabilizer bar, dividing grids, applying load F of 5000N at the suspension position C of the swing arm, and performing ANSYS simulation on the deformation of the stabilizer bar system to obtain a deformation simulation cloud picture, as shown in FIG. 6, wherein the deformation displacement F of the stabilizer bar system at the outermost end A of the swing arm is_AMeasured as

f_A＝19.811mm；

The deformation displacement f of the outermost end A of the swing arm is obtained according to ANSYS simulation_A19.811mm, swing arm length l₁380mm, the distance delta l from the suspension position C of the swing arm to the outermost end A₁47.5mm, suspension distance L of stabilizer bar_c1500mm, 5000N of load F applied at the suspension position C of the swing arm, and k calculated in step (2)_x＝2.1113×10⁶N/m, using the geometric relationship between the stabilizer bar system deformation and the swing arm displacement, as shown in FIG. 4, the roll angle stiffness of the internally biased non-coaxial cab stabilizer bar systemThe ANSYS simulation verification value is calculated, namely

f_{ws} = f_{C} + \frac{F}{k_{x}} = 19.978 mm;

Therefore, ANSYS simulation verification value of roll angle rigidity of stabilizer bar systemAnd design requirement valueThe relative deviation is only 0.447 percent; the result shows that the design method of the outer diameter of the torsion tube of the internally-biased non-coaxial cab stabilizer bar system provided by the invention is correct, and the parameter design value is accurate and reliable.

Example two: the structure of a certain internal offset non-coaxial cab stabilizer bar system is the same as that of the first embodiment, as shown in fig. 2, wherein a torsion tube 4 is not coaxial with a torsion rubber bushing 3, and the internal offset T of the torsion tube is 50 mm; distance L between two left and right swing arms 1_c1400mm, the suspension distance of the stabilizer bar; distance l between suspension rubber bushing 2 and torsion rubber bushing 3₁350mm, namely the length of the swing arm; distance delta l from suspension position C of swing arm to outermost end A₁52.5 mm; length L of torsion tube 4_w1000mm, 40mm of inner diameter D and the outer diameter D as the design amount; the structures of the left rubber bushing and the right rubber bushing are completely the same, as shown in FIG. 3; wherein the inner diameter d of the inner circle sleeve 5_x35mm and 5mm wall thickness; length L of rubber sleeve 6_x40mm, inner circle radius r_a22.5mm, outer radius r_b37.5 mm. The material properties of the stabilizer bar and the rubber bushing are the same as those of the first embodiment, that is, the elastic modulus E of the torsion tube is 200GPa, and the poisson ratio μ is 0.3; modulus of elasticity E of rubber bushing_x7.84MPa, Poisson ratio mu_x0.47. The roll angle rigidity design required value of the cab stabilizer bar systemThe outer diameter D of a torsion tube of the inner offset non-coaxial cab stabilizer bar system is designed, and the roll angle rigidity under the load F-5000N is verified and ANSYS is verified。

The same procedure as in the first embodiment is adopted to design the outer diameter D of the torsion tube of the internally biased non-coaxial cab stabilizer bar system, namely:

according to the design requirement value of the roll angle rigidity of the stabilizer bar systemSuspension distance L_c1400mm, the roll linear rigidity K of the cab stabilizer bar system_wsIs calculated from the design requirement value of (1), i.e.

(2) Radial stiffness k of rubber bushing_xThe calculation of (2):

according to the inner circle radius r of the rubber sleeve_a22.5mm, outer radius r_b37.5mm, length L_x40mm, modulus of elasticity E_x7.84MPa, Poisson ratio mu_x0.47, the radial stiffness k of the rubber bushing of the cab stabilizer bar_xPerform calculations, i.e.

Wherein,

bessel correction function I (0, α r)_b)＝214.9082，K(0,αr_b)＝3.2117×10^-4；

I(1,αr_b)＝199.5091，K(1,αr_b)＝3.4261×10^-4；

I(1,αr_a)＝13.5072，K(1,αr_a)＝0.0083，

I(0,αr_a)＝15.4196，K(0,αr_a)＝0.0075；

according to the length L of the torsion tube_W1000mm, Poisson's ratio mu of material 0.3, internal offset T50 mm, and arm length l₁350mm, load factor beta for torsional rubber bushing_FPerform calculations, i.e.

according to the length l of the swing arm₁350mm, 50mm, and k calculated in step (2)_x＝4.2085×10⁶N/m, beta calculated in step (3)_FEquivalent combined linear stiffness K of rubber bushing of non-coaxial stabilizer bar as 0.468_xPerform calculations, i.e.

(5) The design of the outer diameter D of the torsion tube of the internal bias non-coaxial cab stabilizer bar system comprises the following steps:

according to the length L of the torsion tube_w1000mm, 42mm inner diameter d, 200GPa elastic model E, 0.3 Poisson's ratio mu, 50mm inner offset T, and length l of swing arm₁K calculated in step (1) 350mm_ws＝5.19045×10⁵N/m, and K calculated in step (4)_x＝8.7711×10⁵N/m, the outside diameter D of the torsion tube of the internally biased non-coaxial cab stabilizer bar system is designed, namely

Wherein the roll stiffness of the cab stabilizer bar systemThe curve of the change with the outer diameter D of the torsion tube is shown in figure 7;

utilizing ANSYS finite element simulation software, establishing a simulation model according to the designed outer diameter D of the torsion tube of 48.0mm and other structural parameters and material characteristic parameters of the stabilizer bar system, dividing grids, applying load F of 5000N at the suspension position C of the swing arm, and carrying out ANSYS simulation on the deformation of the stabilizer bar system to obtain a deformation simulation cloud picture, as shown in FIG. 8, wherein the deformation displacement F of the stabilizer bar system at the outermost end A of the swing arm is_AIs composed of

f_A＝17.617mm；

Deformation displacement f of stabilizer bar system at outermost end A of swing arm obtained according to ANSYS simulation_A17.617mm, swing arm length l₁350mm, the distance delta l from the suspension position C of the swing arm to the outermost end A₁52.5mm, suspension distance L of stabilizer bar_c1400mm, 5000N of load F applied at the suspension position C of the swing arm, and k calculated in step (2)_x＝4.2085×10⁶N/m, using the geometric relationship between the stabilizer bar system deformation and the swing arm displacement, as shown in FIG. 4, the roll angle stiffness of the internally biased non-coaxial cab stabilizer bar systemThe ANSYS simulation verification value is calculated, namely

f_{ws} = f_{C} + \frac{F}{k_{x}} = 16.5072 mm;

Therefore, the simulation verification value of ANSYS of the roll angle rigidity of the stabilizer bar systemAnd design requirement valueThe relative deviation is only 0.186%; the design method for the outer diameter of the torsion tube of the internally-biased non-coaxial cab stabilizer bar system is correct, and the parameter design value is accurate and reliable.

Claims

1. The design method of the outer diameter of the torsion tube of the internal bias non-coaxial cab stabilizer bar system comprises the following specific design steps:

according to the design requirement value of the roll angle rigidity of a cab stabilizer bar systemSuspension distance L of stabilizer bar_cRoll of cab stabilizer bar systemLinear stiffness K_wsIs calculated from the design requirement value of (1), i.e.

(2) Radial stiffness k of rubber bushing_xThe calculation of (2):

k_{x} = \frac{1}{u (r_{b}) + y (r_{b})};

Wherein,

I(1,αr_a)，K(1,αr_a)，I(0,αr_a)，K(0,αr_a)；

(6) ANSYS simulation verification of the system rigidity of the internally biased non-coaxial cab stabilizer bar:

Deformation displacement f of stabilizer bar system at outermost end of swing arm obtained according to ANSYS simulation_ALength of swing arm l₁Distance Deltal from suspension position of swing arm to outermost end₁Suspension distance L of stabilizer bar_cA load F applied at the suspension position of the swing arm, and the radial stiffness k of the rubber bushing calculated in step (2)_xAnd the rigidity of the roll angle of the stabilizer bar system in the internally biased non-coaxial cab is realized by utilizing the geometrical relationship between the deformation of the stabilizer bar system and the displacement of the swing armThe ANSYS simulation verification value of the test piece is calculated,namely, it is

f_ws＝f_C+F/k_x；

K_{ws} = \frac{F}{f_{ws}};