價格：免費
更新日期：2018-12-18
檔案大小：1.8M
目前版本：1.0
版本需求：Android 2.2 以上版本
官方網站：http://hyc-tech.com/springs/
Email：hycSprings@gmail.com
聯絡地址：48408 Red Run Drive Red Run Drive Canton, MI 48187
Torsion Spring Mechanical Formulas
D: Mean coil diameter, (mm)
d: Diameter of round wire, (mm)
N: Number of coils including the fraction portion
E: Modulus of elasticity, (MPa)
θ: Deflection, (degree)
S: Spring Rate, (N-mm/degree)
σ: Bending stress, (Mpa)
T: Moment or torque, (N-mm)
b: Width along spring axial direction, (mm)
h: Thickness along coil radial direction, (mm)
L1: Leg 1 length, (mm)
L2: Leg 2 length, (mm)
Round Wire:
Deflection θ = (64T/Eπd^4) [(L1+L2)/3 + NπD] (180/π)
Spring Rate S = (Ed^4 π^2) / { 11520 [ (L1+L2)/3 + NπD ] }
Bending stress σ = K (32T/πd^3), where K = c/(c-0.75), c=D/d
Rectangular Wire:
Deflection θ = (12T/Ebh^3) [(L1+L2)/3 + NπD] (180/π)
Spring Rate S = (Ebh^3π) / { 2160 [ (L1+L2)/3 + NπD ] }
Bending stress σ = K (6T/bh^2), where K = c/(c-2/3), c=D/d
The deflection θ of the torsion spring with legs is derived as follows. The total deflection comes from two portions: the coils body and the legs.
The coil portion deflection θc is equal to TLc/(EI) where Lc is the total length of the coil wire.
The leg portion of deflection θg is equal to (Leg end transverse displacement)/(leg Length Lg).
The transverse displacement of the beam Lg is FLg^3/(3EI), where F is the end force.
The angle due to leg bending is FLg^3/(3EI Lg) = TLg^2/(3EI Lg) = TLg/(3EI).
Combine these two portions and substitute the section area moment of inertia, and convert to degree, we have the equation listed above.
Spring Life
Torsion springs are generally unsuitable for fatigue applications due to the friction and wear which occurs between adjacent coils and between the inside coil surface and supporting mandrel. Highly unpredictable factors such as degree and type of lubricant, surface roughness effects and the relative hardness of spring and mandrel have a significant influence on the actual fatigue life achieved in any particular service application. As a consequence if a torsion spring is to be used in a fatigue application, confirmatory sample testing should be carried out which simulates the actual service operation and environment as closely as possible.
Torsion Spring Size Constraints
Coil should fit inside the constraints of
Outer diameter is less than the space limit
Inner diameter at full load is larger then the mandrel limit
Maximum loaded body length should be less than the space limit
Stress to UTS ratio should be within 70%. Refer to "Material & Wire UTS" tab for material UTS values.
