To provide a stable surface and a unlimited tilt position in an operating range by connecting a base member and a top member by a pivot member and adjusting and holding the position of the top member by a conical clutch mechanism in the circumference of the pivot member.

When the tilt position of a top member 14 is necessary to be adjusted, a force applying to tilt the top member 14 overcomes a prescribed friction force between a tapered inside surface of a floating clutch board and a first top pivot member conical zone 36 and rotates the whole parts of the clutch mechanism 18 except for the floating clutch board 70. When the force on the top member 14 is not sufficient enough for overcoming the friction force, the pivot member 16 stops rotation. When the force is removed, unlimited tilt position can be obtained in every position. For example, even when a touch screen mounted on the top member 14 is operated, the friction force is sufficiently large to provide the stable surface. This constitution can provide the stable surface for operating a terminal and the unlimited tilt position in the operating range.