| 摘要 |
<p>A projection (33) is formed on an end surface of (32) a first pivoting member (3). A short recess (43) and a long recess (44) are formed in an end surface (42) of a second pivoting member (4). On both ends of the short recess (43) are formed engagement surfaces (43a, 43b) for preventing, with a predetermined force, relative pivoting of the first and second pivoting members (3, 4) by butting against both ends of the projection (33). On one end of the long recess (44) is formed an inclined surface (44a) for pivotally urging the first pivoting member (3) in one direction relative to the second pivoting member (4) by butting against one end of the projection (33). On the other end of the long recess (44), there is formed an inclined surface (44b) for pivotally urging the first pivoting member (3) in the other direction relative to the second pivoting member (4) by butting against the other end of the projection (33). The inclined surfaces (44a, 44b) are arranged to be symmetrical about a line passing the center between the engagement surfaces (43a, 43b) and perpendicular to the axis of the second pivoting member (4).</p> |
