Part of the production and production of special-shaped spring needs intense discussion and combination of various schemes among the designers in the company. For example, a special-shaped spring suitable for family rowing exercise fitness apparatus can achieve the expected effect only when the non-contact planar scroll spring with hinged outer end is used as its primary resistance.

The special-shaped spring mainly has the complex spatial angle, the irregular bending. The planar scroll spring is a kind of special-shaped spring. The plane scroll spring is a kind of spring which makes the slender material with constant cross-section into the plane spiral linear spring. The production of the plane scroll spring is relatively simple, its stiffness is small, and it generally works under static load. Because the number of coils can be large and the deformation angle is large, more energy can be stored in a smaller volume. Its material section shape can be rectangular (steel strip) or round (steel wire). The planar scroll spring in the special-shaped spring can be divided into two types: non-contact type and contact type.

The manufacture of planar scroll spring the special Archimedes spiral mould should be designed firstly, and then the winding process and heat treatment process should be considered. Before winding, the purchased rectangular steel strip shall be annealed. The hand winding method, lathe winding method and special tool winding method can be used. After the plane scroll spring is made, it can not be taken out immediately. Instead, the die wrapped with the spring should be sent to the heating furnace for heating. When the quenching temperature is raised, the die and spring assembly are taken out and quenched in appropriate oil. Then, the combination is heated to tempering temperature and kept for a period of time before taking out. Each coil of the prepared flat scroll spring should have a uniform transition, no concave convex phenomenon is allowed, the surface should be smooth, the side acute angle chamfering or circular arc. The surface of plane scroll spring should be treated with oxidation treatment or other anti-corrosion treatment.