| 摘要 |
A manhole cover consists of a frame (1, 2, 3) which can be fitted to the edge of the manhole and a lid (4) which can be inserted into and screwed to the frame. The frame is composed of essentially angular sections (1) which have a roughly horizontal support leg (2) and an outer leg (3) directed upwards. The lid (4) is provided with a base (9) and side walls and has a concrete filling or the like. The support legs (2) of the frame sections (1) form a longitudinal groove (10) for inserting a seal (11) and accommodate threaded plates (15) for screw bolts (20) which connect the lid (4) and the frame (1, 2, 3) and pass through thrust pieces (19) extending up to the lid surface. In order to simplify manufacture, dispense with welding work and obtain a better seal, threaded plates (15) are inserted into a longitudinal groove (14), undercut on both sides, of the support legs (2) of the frame sections (1). Furthermore, the side walls of the lid (4) are likewise formed by essentially angular sections (5) with roughly horizontal bearing legs (7) which carry a base plate (9). Attached above each bearing leg (7) are two retaining strips (16, 17) which overlap a widened foot (18) of the thrust pieces (19). <IMAGE>
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