Abstract: A spring assembly having a coil containing a core and methods and apparatus for manufacturing the same are disclosed. The coil includes a core between reduced portions of the coil. One device for manufacturing the coil includes a coiling machine having an insert device operable with a coiler. The coiler is programmed to form coils of appropriate diameter along the length of the coil, including a diameter sufficiently large to contain the core and two diameters sufficiently small to retain the core in the coil. The insert device transfers the core to the coil after the first small diameter is formed and before the second small diameter is formed. The coil with the core contained between the two small diameters is thereby manufactured in a unified automated process.

Abstract: A spring assembly having a coil containing a core and methods and apparatus for manufacturing the same are disclosed. The coil includes a core between reduced portions of the coil. One device for manufacturing the coil includes a coiling machine having an insert device operable with a coiler. The coiler is programmed to form coils of appropriate diameter along the length of the coil, including a diameter sufficiently large to contain the core and two diameters sufficiently small to retain the core in the coil. The insert device transfers the core to the coil after the first small diameter is formed and before the second small diameter is formed. The coil with the core contained between the two small diameters is thereby manufactured in a unified automated process.

Abstract: A spring assembly having a coil containing a core and methods and apparatus for manufacturing same are disclosed. The coil includes a core between reduced portions of the coil. One device for manufacturing the coil includes a coiling machine having an insert device operable with a coiler. The coiler is programmed to form coils of appropriate diameter along the length of the coil, including a diameter sufficiently large to contain the core and two diameters sufficiently small to retain the core in the coil. The insert device transfers the core to the coil after the first small diameter is formed and before the second small diameter is formed. The coil with the core contained between the two small diameters is thereby manufactured in a unified automated process.

Abstract: A multiple torsion spring assembly according to the present invention may be provided with a coiled helical torsion spring. The spring has first and second end coils, and a plurality of intermediate coils between the first and second end coils. The first end coil inner diameter is less than the inner diameter of the intermediate coils. The second end coil inner diameter is less than the inner diameter of the first end coil. The spring may be used to control a throttle return of a throttle body. Methods of manufacturing spring assemblies are also disclosed.