Conical helical springs are mainly divided into two categories: equal-pitch conical helical springs and equal-helix-angle conical helical springs. In the equal-pitch type, the projection of the helix on the bottom surface is an Archimedean spiral, and the pitch t of the effective rings is equal. In the equal-helix-angle type, the projection of the helix on the bottom surface is a logarithmic spiral, and the helix angle an of the effective rings is equal.
Design Standards The design standards for conical helical springs must meet the requirements for dimensional parameters and allowable deviations, including the inner diameter of the small end, the outer diameter of the large end, the free height, and perpendicularity. The allowable deviation for the inner diameter of the small end support ring is specified, and the inner diameter of the support ring is calculated based on 2Rmm Murd. The allowable deviation for the outer diameter of the large end support ring is specified, and the outer diameter of the support ring is calculated based on 2R. The allowable deviation for the free height H is specified; when the conical spring has load requirements, the free height deviation is used as a reference. For conical helical springs with both end faces ground or the large end face ground, their perpendicularity is specified; for conical helical springs with unground end faces, the perpendicularity is not checked, and the supplier and buyer must agree if necessary.
Design Considerations and Characteristics: The truncated cone helical spring has a compact structure and good stability. During operation, it withstands large loads, causing its stiffness to become non-linear. At low loads, its characteristic curve is linear, but it becomes non-linear as the load gradually increases. The stiffness coefficient of the truncated cone helical spring is negatively correlated with the number of effective coils. After entering the non-linear segment, the mechanical characteristic curve of the truncated cone helical spring with a small free height becomes steeper.
