| 摘要 |
<p>The accessory (100) has flaps (110, 120) respectively including a cylindrical wall (117) and a circular opening (127). The opening receives the wall to authorize rotation of the flaps around a rotational axis (Y). An external diameter of the wall is equal to a clearance close to an internal diameter of the opening, such that an external surface of the wall slides on a section of a circular edge of the opening, during rotation of the flaps with respect to each other. Height of the wall varies along a circumference of the wall. A straight slit (128) is extended radially with respect to the edge.</p> |
