Apparatus for making a torsion spring

Abstract From the Canadian patent

An apparatus for making double coil torsion springs such as ones found in reclining office chairs to return the chair to the upright position. The spring has two coils on the same axis connected by an arm. The problem in manufacturing the spring is that to wind both coils around a mandrel at the same time, the spring must be held between the coils during winding and once winding is complete, the coils are trapped on the mandrel by whatever is holding the spring between the coils. A conventional solution is to wind the coils separately slide, them off the end of the mandrel and bend to bring them together, to form the spring. This is slower than winding both simultaneously and difficulties …