| 摘要 |
A manhole cover having an integrated locking system that is self-locking and easy to open. The device includes a cover plate adapted to rest on a manhole cover support surface of a manhole frame so as to be substantially flush with a top portion of the manhole frame and a surrounding surface in which the manhole frame is situated. An anchor on the cover plate is adapted to engage the manhole frame at a first location in a manner that resists lifting of the cover plate proximate to the first location. A locking member on the cover plate is movable between a locked position and an unlocked position. In the locked position, the locking member is adapted to engage the manhole frame at a second location in a manner that resists lifting of the cover plate proximate to the second location. In the unlocked position, the locking member is disengaged from the manhole frame.
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