To provide a hinge device providing large torque without enlarging outer diameter, providing high torque even if retention of a cover body, in embodiment, a display device at a normal usage position and retention of the same at full close and full open position are materialized with a common structure, inexpensive with reduced number of parts by that, automatically closing in a close direction at the full close (0 degree) position and retaining the position, but user-friendly even near the full open (180 degree) position.

This hinge device connecting one member and another member in such a manner capable of opening and closing consists of a fixed bracket fixed on one member, a shaft rotatably supported by the fixed bracket and having another member fixed and attached thereon, and a flat spring of a roughly U-shape. The flat spring is installed on the fixed bracket with both side parts forming a roughly U-shape pressed on an outer circumference surface of the shaft.