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A manhole cover, in particular for roads.
A manhole cover, in particular for roads.
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机译：井盖，特别是道路的井盖。
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摘要
1,142,123. Manholes. BROADS MFG., CO., Ltd. 22 Dec., 1967 [20 March, 1967], No. 13007/67. Heading E1G. A manhole is ventilated through apertures 10 in the top of the fixed frame 1 in which the cover 4 is seated. As shown the apertures 10 comprise gaps between webs 9, and the cover is in two triangular sections supported by corner bosses 3, 5 so as to leave an additional ventilation gap 15 along each side. The cover sections are recessed to provide a ventilation opening 7A, and have key-engaging sockets 8. The frame has a lower flange 12 with two recessed lugs 13 for supporting a grid or pan beneath the cover 4.
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