Tension spring end holder

The above design solutions of tension spring holders are ideal where there is a requirement for rotation around the spring axis. Rotation is usual requirement with cases of adjusting the preload of the spring. At the upper design we can see how the end holder is secure inside a hollow screw. The hollow screw has a screwdriver slot (ISO 2380), when we screw (or unscrew), we increase (or decrease) the amount of tension of the spring while the spring does not rotate. The same end holder can be used as a standalone part, holding the spring. If the tension spring acts on high speed rotate component (a lever), the end holder must be replaceable (increased wear).