In the case of a compression spring with one winding at each end ground and is a closed-end, it is said that the spring will stand firmly and the squareness is easier to obtain if the total number of coils is 〇〇.5. Is it correct?
Also, I heard that the bending causes side force in the compression direction. Please tell me more about this. If so, is there a formula for calculating the side force?
Thank you for your question!
The reason why it is said that 〇〇.5 turns are good for compression coil springs is that it helps to adjust the number of active coils. Based on the idea that when the spring is compressed, the spring constant becomes weaker when the number of active coils is large, we often use〇〇.5 turns.
The squareness depends on the processing accuracy when there is no load, but there may be differences in body bending and buckling when compressed.
In addition, since the compression coil springs are processed into a spiral shape, compression causes a change in the coil diameter and a rotational moment, which also cause side force.
Therefore, there is no particular formula for calculating the side force. Although it can be calculated by the FEM analysis, it is often difficult to obtain an accurate calculation result because it is often inconsistent depending on the specific spring.
