PURPOSE: To provide a flip spring mechanism with which fixing of a leaf spring to a fixing member is simplified and facilitated.

CONSTITUTION: A leaf spring 10 is composed of two confronting legs 11 and a coupling 12 formed in approx U shape from a sheet spring material, a part to be pressed 13 installed in continuity from the coupling 12 between the two legs 11, and a pressing part 14 which is formed in continuity at the coupling 12 so as to be in opposite direction to the part to be pressed 13. The arrangement further includes two fixing parts 21 for fixing of the legs 11 and also a fixing member 20 which can deform in the direction admitting the approach of the two fixing parts 21. After the legs 11 are fixed to respective fixing parts 21, deformation is made so that the parts 21 approach, and thereby the part pressed 13 and the pressing part 14 are dislocated oppositely from each other about the plane including the legs 11, and the pressing part 14 is inversively dislocated to the opposite side when the part 13 is pressed and displaced in excess of the plane incl. legs 11.