SPRINGS TORSION



	TORSION SPRINGS
	Torsion springs are stressed in bending or tensile, as some prefer to call it. There is often confusion with these springs, which are essentially a helically coiled body with some kind of leg end fixings. They function by winding up or by unwinding. However it is always preferable to design them to function in winding up mode i.e. the number of turns in the spring increasing as the diameter reduces, this is because the maximum operating stresses are considerably higher when winding up. Torsion springs can be single (one helical body) or double (two helical bodies with a connecting piece) mostly coiled from round wire but other cross sections are often used. They can be close coiled or open coiled and generally this will depend on fit and function requirements where advise from experienced designers is important and no simple general set of rules can apply. There are other structural forms of torsion springs, which are more complex in function but are necessitated by the assembly product actuation system. Here are examples of some commonly used end forms:



	The torque exhibited by torsion springs is generally linear but there may be other considerations that have to be noted when evolving a design. Friction between spring and helical body support pin can have an affect. Torsion springs that have long legs or connecting pieces will have some deflection in them which will affect the desired torque / force required in the design. Kato-Entex produces torsion springs in wire diameters from 0.1mm to 14.0mm diameter from small to very high volume. For those potential users of very high volumes where wire diameters are below about 1.6mm diameter then our sister company Kato Precision have high speed torsion coilers designed and built within the Advanex group to give you very competitive unit prices with a high product quality.