| 摘要 |
PROBLEM TO BE SOLVED: To easily keep a position at an arbitrary angle in the opening and closing of a lid member with approximately constant frictional force by determining a surface hardness of a rotary shaft of a shaft member within a range above a specific value. SOLUTION: A shaft member 10 is provided with surface hardness Hv (Vickers hardness) of above 800 by being made out of an age-hardening type SUS material, a high Si aluminium alloy and the like. When the surface hardness Hv of the shaft member 10 is low, the entanglement in an initial period of its rotation is increased, and the stick-slip is increased, and when the surface hardness Hv is high, the engaglement in the initial period of its rotation and the stick-slip can be decreased. In an experimental view, as a point of inflection having a maximum value, is found in a zone of the surface hardness Hv of 700-750, a friction hinge device 1 can exercise the superior function in the practical use when it has the surface hardness Hv not less than 800. |
