Spring Force of Constant Torque Spring and Wing-up Spring
contact spring pile-up (contact spring assembly)
half-elliptic spring(semi-elliptic spring)
hard spring， hardening spring
plate spring (plate-form-spring)
plate-form spring (plate spring)
Shape and Spring Back of Constant Torque Spring
soft spring ，softening spring
soft spring， softening spring
spring wheat spring corn intercropping system
analogous fore cast method
arrangement on fore and aft