| 摘要 |
<p>897,553. Manhole covers. BROADS MANUFACTURING CO. Ltd., and SAINS, D. W. Nov. 9, 1960 [Nov. 26, 1959], No. 40291/59. Class 107 [Also in Group XXV] In a manhole cover including a frame 2, a counter-balanced cover I and a supporting stay 9, a lever 4 pivoted to a point 5 fixed relative to the frame supports a counterweight 7 and the stay 9 comprises a slotted arm, a stud 12 on the lever 4 slidably engaging in the slot 10 which is shaped at 13 to retain the stud when the cover is opened. A locking lever 14 is disengageable from a stop 17 by pressing on a plate 18 or inserting a key in a hole (not shown) in the cover. In an alternative form of locking means, Fig. 6, a lever 19 is pivotable horizontally about a point 20 to bring an end 21 into and out of engagement with a flange 22 on the frame 2.</p> |
