Calculation method of silicone oil torsional vibration damper housing stiffness

Abstract

The present invention discloses a method for calculating the stiffness of a silicone oil torsional vibration damper housing, and the specific steps are as follows: S1. Assume that the space between the shock absorber housing and the shock absorber inertia ring is filled with a fluid with a viscosity of , and rotates at a constant relative angular velocity. According to Newton's viscosity law, the viscous shear stress at the shock absorber housing radius of is: and the viscous shear stress formulas of the five regions are obtained; S2. When the shock absorber is working, according to the viscous shear stress formulas of the five regions, the torque diagrams of the five regions of the housing can be drawn, from the outer ring ⑤ → the right side wall ④ of the annular ring → the left side wall ③ → the inner ring ② → the right side wall ① of the center hole. By deducing the value of the torque, it can be known that the torsional amplitude of the upper left corner of the shock absorber housing is the largest; the shock absorber housing stiffness is calculated by the formula. The silicone oil torsional vibration damper housing stiffness calculation method of the present invention can adapt to a variety of silicone oil torsional vibration damper sizes, does not require finite element analysis to obtain the housing torsional stiffness, is suitable for programming calculation, and the calculation result differs from the finite element method calculation by about 2%.

Description

Technical Field

[0001] The invention relates to the technical field of engine vibration damper manufacturing, and in particular to a method for calculating the rigidity of a silicone oil torsional vibration damper housing. Background Art

[0002] The engine torsional vibration damper consists of a housing, a vibration damper inertia ring, silicone oil, and bearings. The torsional stiffness of the housing is an important indicator when designing the vibration damper, as it is related to the magnitude of the torsional vibration amplitude and the stability of the engine operation. The most commonly used method for calculating the stiffness of the silicone oil vibration damper housing is the finite element analysis method.

[0003] The silicone oil torsional vibration damper of the present invention is as follows Figure 1 As shown, it includes a shock absorber housing, in which a shock absorber inertia ring is arranged. A gap is reserved between the shock absorber inertia ring and the shock absorber housing. For the sake of convenience, the parts of the shock absorber housing relative to the shock absorber inertia ring are defined as: outer ring ⑤, inner ring ②, annular left side wall ③, annular right side wall ④, and right side wall of the center hole ①.

[0004] The inventors discovered during the process of implementing the present invention that:

[0005] Patent application number 2018102617146 states that when calculating housing stiffness using finite element analysis, it is necessary to draw a model of the shock absorber housing and import it into finite element analysis software. After defining the material and mechanical boundary conditions, the calculation is submitted, and the torsional stiffness value is obtained through post-processing. Using finite element analysis is complex, slow, and not suitable for programming calculations.

[0006] Patent document No. 2023105779425 proposes a formula for calculating shock absorber stiffness, but the shock absorber stiffness is not the shock absorber housing stiffness;

[0007] Patent document No. 2018105899356 proposes a method for calculating the stiffness of a diesel engine coil spring torsional vibration damper, patent document No. 201710649695X proposes a stiffness and stress calculation model for a diesel engine leaf spring torsional vibration damper, and patent document No. 2015205586349 proposes a seat shock absorber stiffness adjustment device, but these methods are not applicable to silicone oil shock absorbers.

[0008] From the above analysis, it can be seen that the existing methods cannot quickly calculate the stiffness of the silicone oil shock absorber shell based on the size and shell material of the silicone oil shock absorber shell. The finite element analysis method is complex to set up and not convenient for programming calculations. It is urgent to derive the mathematical relationship between the size, shell material and stiffness of the silicone oil shock absorber shell. Summary of the Invention

[0009] In order to solve the problems existing in the prior art, the present invention proposes a method for calculating the stiffness of a silicone oil torsional vibration damper housing, clarifies the mathematical relationship between the size of the silicone oil vibration damper housing, the housing material and the stiffness of the vibration damper housing, thereby solving the technical problem that the finite element analysis method is complex to set up and inconvenient for programming and calculation.

[0010] Invention concept: Taking into account the influencing factors such as the installation method of the silicone oil vibration damper, the distribution of the damping force on the inner wall of the silicone oil vibration damper housing, the housing material and size, the torsional deformation angle of the silicone oil vibration damper housing is calculated through theoretical deduction, thereby obtaining the value of the torsional stiffness.

[0011] To this end, the technical solution of the present invention is: a method for calculating the stiffness of a silicone oil torsional vibration damper housing, the specific steps are:

[0012] S1. Assume that the space between the shock absorber housing and the shock absorber inertia ring is filled with a viscosity of The relative angular velocity between the fluid, the inertia ring of the shock absorber and the shock absorber housing Uniform rotation, according to Newton's law of viscosity, the radius of the shock absorber shell is Viscous shear stress at for:

[0013] (Formula 1)

[0014] Combined with the specific structure of the silicone oil torsional vibration damper, the silicone oil fills the gap between the shock absorber housing and the shock absorber inertia ring. When relative displacement occurs between the shock absorber housing and the shock absorber inertia ring, the viscous shear stress on the inner cavity of the shock absorber housing is not uniformly distributed. Instead, the larger the radius, the greater the viscous shear stress. According to the characteristics of the viscous shear stress on various parts of the shock absorber housing, the housing is divided into five regions: the right side wall of the center hole ①, the inner ring ②, the left side wall of the annular ring ③, the right side wall of the annular ring ④, and the outer ring ⑤. The viscous shear stresses in these five regions are:

[0015] (Formula 2)

[0016] (Formula 3)

[0017] (Formula 4)

[0018] (Formula 5)

[0019] (Formula 6)

[0020] in, to The viscous shear stresses corresponding to the five regions are: 、 、 、 、 is the relevant size corresponding to the shock absorber;

[0021] S2. When the shock absorber is working, the torsion amplitude at the upper left corner of the shock absorber housing is the largest. According to Formula 2-Formula 6, a torque diagram of the five areas of the housing can be drawn. The torque value can be deduced from the outer ring ⑤ → the right side wall ④ → the left side wall ③ → the inner ring ② → the right side wall ① of the center hole.

[0022] The maximum torque in the outer ring area ⑤ is ,

[0023] The maximum torque in the area ④ of the right side of the annular wall is ,

[0024] The maximum torque in the area ③ on the left side of the annular wall is ,

[0025] The maximum torque in the inner ring area ② is ,

[0026] The maximum torque in the area ① on the right side of the center hole is ,

[0027] Therefore, the maximum torque on the shock absorber housing is: (Formula 7)

[0028] S3. According to the torque diagram, calculate the maximum torsion angle of the shell along the path of the right side wall of the center hole ①→the right side wall of the ring ④→the outer ring ⑤.

[0029] The maximum torsion angle of the area ① on the right side of the central hole is ,

[0030] The maximum torsion angle of the area ④ on the right side of the annular wall is ,

[0031] The maximum torsion angle of the outer ring area ⑤ is: (Formula 8)

[0032] S4. Calculate the shock absorber housing stiffness as:

[0033] (Formula 9)

[0034] According to the above formula, the torsional stiffness of the shell can be calculated.

[0035] Preferably, the dimensions and material parameters of a certain shock absorber are substituted into Formula 9, where: a=70.5 mm; R=136.025 mm; c=78.975 mm; B=15.025 mm; L1=9 mm; L2=38 mm; L3=3 mm; L4=3.95 mm; δ1=0.5 mm; δ2=0.55 mm; δ3=1.275 mm; d=140 mm; and h=25 mm. The calculated shell stiffness is 8420000 N m / rad, and the shell stiffness calculated using finite element analysis software is 8250000 N m / rad, with a difference of 2.02%.

[0036] Beneficial effects: The method for calculating the shell stiffness of the silicone oil torsional vibration damper of the present invention can adapt to a variety of silicone oil torsional vibration damper sizes, does not require finite element analysis to obtain the shell torsional stiffness, is suitable for programming calculations, and the calculation results are about 2% different from the results calculated by the finite element method, which can replace finite element analysis. Compared with finite element software, if the finite element software calculation process is required every time the shock absorber size is changed, the process is complicated and slow. However, when using the formula of the present invention for calculation, thousands of attempts can be made in one second, and the optimal size can be found quickly. The formula of the present invention has a faster calculation speed, is convenient for programming calculations, and is convenient for rapid optimization of shock absorber size. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG1 is a schematic diagram of a silicone oil torsional vibration damper according to the present invention.

[0038] Figure 2 1 is a torque diagram of the silicone oil torsional vibration damper of the present invention. DETAILED DESCRIPTION

[0039] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings, but this embodiment should not be understood as limiting the present invention.

[0040] The following describes the specific application of the present invention in conjunction with an example of calculating the housing stiffness of a silicone oil torsional vibration damper. The specific implementation steps are as follows:

[0041] S1. Assume that the space between the shock absorber housing and the shock absorber inertia ring is filled with a viscosity of The fluid between the shock absorber inertia ring and the shock absorber housing is at a relative angular velocity Uniform rotation, according to Newton's law of viscosity, the radius of the shock absorber shell is Viscous shear stress at for:

[0042] (Formula 1)

[0043] according to Figure 1The specific structure of the silicone oil torsional vibration damper is that the silicone oil fills the gap between the shock absorber housing and the shock absorber inertia ring. When relative displacement occurs between the shock absorber housing and the shock absorber inertia ring, the viscous shear stress on the inner cavity of the shock absorber housing is not uniformly distributed. Instead, the larger the radius, the greater the viscous shear stress. According to the characteristics of the viscous shear stress on various parts of the shock absorber housing, the housing is divided into five regions: the right side wall of the center hole ①, the inner ring ②, the left side wall of the annular ring ③, the right side wall of the annular ring ④, and the outer ring ⑤. The viscous shear stresses in these five regions are:

[0044] (Formula 2)

[0045] (Formula 3)

[0046] (Formula 4)

[0047] (Formula 5)

[0048] (Formula 6)

[0049] in, to The viscous shear stresses corresponding to the five regions are: 、 、 、 、 are the relevant dimensions of the shock absorber, such as Figure 1 As marked in;

[0050] S2. When the shock absorber is working, Figure 1 The torsion amplitude is the largest at the upper left corner of the middle shock absorber housing. According to Formula 2-Formula 6, the torque diagram of the five areas of the housing can be drawn. The torque value can be deduced from the outer ring ⑤→ the right side wall ④→ the left side wall ③→ the inner ring ②→ the right side wall ① of the center hole.

[0051] The maximum torque in the outer ring area ⑤ is ,

[0052] The maximum torque in the area ④ of the right side of the annular wall is ,

[0053] The maximum torque in the area ③ on the left side of the annular wall is ,

[0054] The maximum torque in the inner ring area ② is ,

[0055] The maximum torque in the area ① on the right side of the center hole is ,

[0056] Therefore, the maximum torque on the shock absorber housing is:

[0057] (Formula 7)

[0058] S3. According to the torque diagram, calculate the maximum torsion angle of the shell along the path of the right side wall of the center hole ①→the right side wall of the ring ④→the outer ring ⑤.

[0059] The maximum torsion angle of the area ① on the right side of the central hole is ,

[0060] The maximum torsion angle of the area ④ on the right side of the annular wall is ,

[0061] The maximum torsion angle of the outer ring area ⑤ is:

[0062] (Formula 8)

[0063] in, is the shear section modulus of the shell material.

[0064] S4. Calculate the shock absorber housing stiffness as:

[0065] (Formula 9)

[0066] According to the above formula, the torsional stiffness of the shell can be calculated.

[0067] In this embodiment, the dimensions and material parameters of a certain vibration absorber are substituted into Formula 9, where: a=70.5 mm; R=136.025 mm; c=78.975 mm; B=15.025 mm; L1=9 mm; L2=38 mm; L3=3 mm; L4=3.95 mm; δ1=0.5 mm; δ2=0.55 mm; δ3=1.275 mm; d=140 mm; and h=25 mm. The calculated shell stiffness is 8,420,000 N m / rad. The shell stiffness calculated using finite element analysis software is 8,250,000 N m / rad, with a difference of 2.02%. This indicates that the shell stiffness can replace finite element analysis.

[0068] At the same time, compared with finite element software, if the finite element software needs to be used for calculation every time the shock absorber size is changed, the process is complicated and slow. However, when using the formula of the present invention for calculation, thousands of attempts can be made in one second, and the optimal size can be found quickly. The formula of the present invention has a faster calculation speed, is convenient for programming and calculation, and is convenient for rapid optimization of the shock absorber size.

[0069] Parts not described in detail in this specification are well-known technologies in the art.

[0070] Through the description of the above processing method, those skilled in the art should understand that the present invention is not limited to the above specific embodiments, and that improvements and substitutions based on the present invention using the known technologies in the art fall within the scope of protection of the present invention and should be defined by the claims.

Claims

1. Calculation method of silicone oil torsional vibration damper housing stiffness, the specific steps are: S1. Assume that the space between the shock absorber housing and the shock absorber inertia ring is filled with a viscosity of The fluid between the shock absorber inertia ring and the shock absorber housing is at a relative angular velocity Uniform rotation, according to Newton's law of viscosity, the radius of the shock absorber shell is Viscous shear stress at for: (Formula 1) Combined with the specific structure of the silicone oil torsional vibration damper, the silicone oil fills the gap between the shock absorber housing and the shock absorber inertia ring. When relative displacement occurs between the shock absorber housing and the shock absorber inertia ring, the viscous shear stress on the inner cavity of the shock absorber housing is not uniformly distributed. Instead, the larger the radius, the greater the viscous shear stress. According to the characteristics of the viscous shear stress on various parts of the shock absorber housing, the housing is divided into five regions: the right side wall of the center hole ①, the inner ring ②, the left side wall of the annular ring ③, the right side wall of the annular ring ④, and the outer ring ⑤. The viscous shear stresses in these five regions are: (Formula 2) (Formula 3) (Formula 4) (Formula 5) (Formula 6) in, to The viscous shear stresses corresponding to the five regions are: 、 、 、 、 is the relevant size corresponding to the shock absorber; S2. When the shock absorber is working, the torsion amplitude at the upper left corner of the shock absorber housing is the largest. According to Formulas 2-6, a torque diagram can be drawn for the five regions of the housing. The torque value can be deduced from the outer ring ⑤ → the right side wall ④ → the left side wall ③ → the inner ring ② → the right side wall ① of the center hole. The maximum torque in the outer ring area ⑤ is , The maximum torque in the area ④ of the right side of the annular wall is , The maximum torque in the area ③ on the left side of the annular wall is , The maximum torque in the inner ring area ② is , The maximum torque in the area ① on the right side of the center hole is , Therefore, the maximum torque on the shock absorber housing is for: (Formula 7) S3. According to the torque diagram, calculate the maximum torsion angle of the shell along the path of the right side wall of the center hole ①→the right side wall of the ring ④→the outer ring ⑤. The maximum torsion angle of the area ① on the right side of the central hole is , The maximum torsion angle of the area ④ on the right side of the annular wall is , The maximum torsion angle of the outer ring area ⑤ is: (Formula 8) S4. Calculate the shock absorber housing stiffness for: (Formula 9) According to the above formula, the torsional stiffness of the shell can be calculated.

2. The method for calculating the housing stiffness of a silicone oil torsional vibration damper according to claim 1, wherein: Substituting the dimensions and material parameters of a certain shock absorber into Formula 9, where: a=70.5 mm, R=136.025 mm, c=78.975 mm, B=15.025 mm, L1=9 mm, L2=38 mm, L3=3 mm, L4=3.95 mm, δ1=0.5 mm, δ2=0.55 mm, δ3=1.275 mm, d=140 mm, and h=25 mm, the calculated shell stiffness is 8,420,000 N m / rad. The shell stiffness calculated using finite element analysis software is 8,250,000 N m / rad, a difference of 2.02%.

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