A——cross-sectional area of spring material (mm²); equivalent bending stiffness (N/mm); coefficient
a——The length of the side of the cross-section material perpendicular to the spring axis (mm); coefficient
B——The bending stiffness of the plate (N/mm); coefficient
b——The ratio of height to diameter; the length of the side of the distance section material parallel to the spring axis (mm); coefficient
C-spiral spring winding ratio; disc spring diameter ratio; coefficient
D——Spring diameter (mm)
D1——Spring inner diameter (mm)
D2——Outer diameter of spring (mm)
d——The diameter of spring material (mm)
E——Spring modulus (MPa)
F——load of spring (N)
F’-the stiffness of the spring
Fj——the working limit load of the spring (N)
Fo——The initial tension of the cylindrical tension spring (N)
Fr——Radial load of the spring (N)
F’r——The radial stiffness of the spring (N/mm)
Fs——Test load of spring (N)
f——Deformation amount of spring (mm)
fj——deformation under working limit load Fj (mm)
fr-the static deformation of the spring (mm)
fs——the deformation of the spring under the test load Fs (mm); the linear static deformation (mm)
fo——The assumed deformation of the tension spring corresponding to the local tension Fo (mm); the center deformation of the diaphragm (mm)
G——The shear modulus of the material (MPa)
g——acceleration of gravity, g=9800mm/s²
H——The working height (length) of the spring (mm)
Ho——the free height (length) of the spring (mm)
Hs——The height (length) under the spring test load (mm)
h——The height of the inner load cone of the disc spring (mm)
I——Moment of inertia (mm4)
Ip——Polar moment of inertia (mm4)
K——curvature coefficient; coefficient
Kt-temperature correction coefficient
ρ——The density of the material (kg/mm³)
σ——The normal stress of the spring when it is working (Mpa)
σb——Material tensile strength (Mpa)
σj——the working limit stress of the material (Mpa)
σs——The tensile yield point of the material (Mpa)
τ——Shear stress when the spring is working (Mpa)
k——Coefficient
L——expanded length of spring material (mm)
l——Expanded length of effective working circle of spring material (mm); free chord length of leaf spring (mm)
M——Bending moment (N·mm)
m——the mass of the object acting on the spring (kg)
ms——the mass of the spring (kg)
N-number of cycles of variable load
n——the number of working turns of the spring
nz——the number of support circles of the spring
n1-the total number of turns of the spring
pˊ——the stiffness of a single spring coil (N/mm)
R——the middle radius of the spring coil (mm)
R1——the inner radius of the spring ring (mm)
R2——The outer radius of the spring ring (mm)
r——damping coefficient
S——Safety factor
T——torque; torque (N·mm)
Tˊ——torsional stiffness (N·mm /(º))
t-the pitch of the spring
tc——steel cable pitch (mm)
U——Deformation energy (N·mm); (N·mm·rad)
V——Volume of spring (mm³)
v——The speed of the impact body (mm/s)
Zm——Bending section coefficient (mm³)
Zt—— torsion section coefficient (mm³)
α——helix angle (º); coefficient
β——Wire rope twisting angle (º); cone half angle (º); coefficient
δ——Axial clearance of spring ring (mm)
δr——Radial clearance of combined spring ring (mm)
ζ——Coefficient
η——Coefficient
θ——torsion angle per unit length of torsion bar (rad)
κ——Coefficient
μ——Poisson’s ratio; length coefficient
ν——The natural frequency of spring (Hz)
Vr——the excitation frequency of the variable load on the spring (Hz)
τb——The shear strength of the material (Mpa)
τj——the working limit shear stress of the spring (Mpa)
τo——Pulsating torsional fatigue limit of the material (Mpa)
τs——the torsional yield point of the material (Mpa)
τ-1——The symmetrical cyclic torsional fatigue limit of the material (Mpa)
φ——torsion deformation angle (º); (rad) (end)