Patent ID: 7213802

Claim:
In a coil spring of closed-end type, said coil spring is characterized in that a coupler, having a length less than a quarter of a circle of the coil, is fixedly mounted between: an outer peripheral surface of a terminal convolution of a coil element rod of the coil spring of closed-end type, said terminal convolution being partially flattened in cross section through a flattening process; and an outer peripheral surface of a subsequent convolution subsequent to said terminal convolution of the coil spring of closed-end type, so that said coupler is brought into close contact with said outer peripheral surface of each of said terminal convolution and said subsequent convolution of the coil spring of closed-end type, whereby an amount of initial deflection of the coil spring of closed-end type is decreased when the coupler is compressed between the outer peripheral surface of said terminal convolution and the outer peripheral surface of said subsequent convolution, wherein said coupler is fixedly held between the terminal convolution and the subsequent convolution of the coil element rod of the coil spring in an uncompressed state of the coil spring without a gap between the outer peripheral surface of the terminal convolution and a first surface of the coupler and without a gap between the outer peripheral surface of the subsequent convolution and a second surface of the coupler.