PURPOSE: To comply easily with the assembly on full automatic basis by putting a body on those of a number of edge receiving springs in coupling which constitute a pair, performing thereafter a separation and wiring of the edge receipt springs, and covering with a sheath.

CONSTITUTION: A crude workpiece is prepared in which a number of edge receipt springs 1 are coupled together on the wiring terminal 10 side through a coupling part 11 and a coupling piece 12, wherein every other pieces 12 are removed, and a body 3 consisting of a base 31 and a cover 32 is put on a pair of springs 1 tying together. Because no power cord 2 is connected with any spring 1, combination can be made without obstruction. A projection 13 is fitted by pressure into the base 31, and spring location and fixation are made. Then the coupling part 11 and coupling piece 12 are punched off and removed. and the springs 1 are put independent, and the cord 2 is caulked to the terminal 10, followed by wiring process. A sheath 4 made of thermo-plastic resin is formed on the periphery of the body 3, and the body 3 and the wiring part are covered to complete the operations.