| 摘要 |
<p>Manhole comprises frame (1), metallic grid (2), and lid (4). Grid has elastic bar (3) with free end (30) having enlarged sec (31) allowing locking of grid in retaining gap (11) of frame. Lid has lug (43) inserted in aperture (32) so as to immobilize lid closed position on frame through grid. By pushing free end in direction indicated by D2, that force induces deflection of elastic bar in same direction so as to release enlarged section from retaining gap.</p> |
