| 摘要 |
PCT No. PCT/CH90/00148 Sec. 371 Date Apr. 17, 1991 Sec. 102(e) Date Apr. 17, 1991 PCT Filed Jun. 18, 1990 PCT Pub. No. WO91/00942 PCT Pub. Date Jan. 24, 1991.The invention concerns a manhole cover with a frame (1) and a grating (3) or cover fitting flush with the frame (1). In order to secure the cover (3) in such a way that it can be easily removed and put back in place, a one-piece securing element (4a) is attached to the frame (1), the securing element (4a) having a locking element (7) at the end of a tab-like retaining element (6) extending obliquely upwards. The locking element (7) engages against a locking surface (9) at the bottom of a recess (8) in the surface of the grating (3) or cover. To unlock the manhole cover, the locking element (7) can be pulled away from the locking surface (9) with a special tool, e.g. a pair of pliers, the retaining element (6) being bent elastically. The securing element (4a) is mounted on the frame (1), embracing shoulders (5a, 5b) so that it is secured by a snap-in connection. The securing element can also be attached to the cover or grating and engage against a locking surface on the frame. |
