To improve assembling accuracy so as to allow stable use for a long time by arranging a pair of cams rotationally relatively and mutually approachably with their axial lines matched with each other and arranging one cam freely movably along its axis in a shaft part integrally arranged in the other cam.

In a hinge device for a cellular phone and the like, a movable side cam 1 fixed in an openable member side is constructed of a substantially disc-shaped head part 11, which has a flat face parallel to the outer circumferential face, and a cylindrical shaft part 12 integrally formed in the center part, and in the connection part between the head part 11 and the shaft part 12, a cam part 13 with a crest-shape in a front side vision is formed. In the shaft part 12 of the movable side cam 1, a substantially projection-shaped hollow type fixed side cam 2 is mounted freely movably and rotationally along its axial direction, and the shaft part 12 is inserted into an insertion hole 33 formed in a bottom part 32 of a bottomed cylindrical guide holder 3 mounted on the outside of the fixed side cam 2. A spring 4 mounted between the fixed side cam 2 and the bottom part 32 energizes the fixed side cam 2 toward the movable side cam 1.