US Patent 7683259 Power supply system

For improving durability of a wiring harness of a power supply system used in a sliding structure, a power supply system includes a casing; a wiring harness; a harness supporter arranged along a base of the casing so as to move freely back-and-forth in the casing; and a constant force spring arranged along the base of the casing. The wiring harness is bent and wired along an outer surface of the harness supporter, and the harness supporter is biased with a spring force by the constant force spring so as to absorb an extra length of the wiring harness. A winding part of the constant force spring is separated from a harness receiving space of the casing, and an end of the constant force spring led from the winding part is connected and fixed to the harness supporter at an outside of the casing.