| 摘要 |
<p>PURPOSE:To enhance manufacturing performance and obtain required lock torque by providing a shaft, a cross-sectional shape along the direction perpendicular to an axis of a coil winding portion of which is narrower than a length of an elliptical short shaft of a close winding portion, having a length equal to that of a long shaft. CONSTITUTION:When a display portion is turned in the closing direction, turning torque is increased by a dead load of the display portion. A close winding portion 40a of a coil spring 40 is turningly displaced in the direction indicated by an arrow E. The close winding portion 40a is expanded by a coil winding portion 39a, to be elastically deformed in such a manner that the falling angle thereof is reduced. Accordingly, return force to return to an original, natural state (a state fallen along an axis where a shape of the close winding portion 40a viewed from an end surface becomes an elliptical shape, wherein a falling angle is theta1), i.e., lock torque is generated in the coil spring 40. Because free turning of the display portion can be restricted by the lock torque, the display portion can be held at a predetermined erecting angle even if a hand is separated from the display portion after adjusting an erecting angel of the display portion.</p> |
