| 摘要 |
1281761 Pipe couplings DOWTY MECO Ltd 19 April 1971 [6 March 1970] 10948/70 Addition to 1154943 Heading F2G Flexible ducting, e.g. for carrying ventilating air in mines, is joined by short lengths of ducting each having at both ends contractile beads or seams as in Specifications 1,223,406 and 1,154,943. In one form, a short length of ducting 5 has at both ends contractile seams 7, each containing a wire ring 13 and an endless ring 6 of rope. The ends of ducts 1, 2 kept open by wire rings 3 are inserted within the ends of the ducting 5, and the seams 7 are then contracted by tightening the ropes 6. As shown, tightening is effected by inserting a captive peg 10 into an external loop 9 in each rope 6, and twisting. In a modification, Fig. 2 (not shown), each endless rope 6 is replaced by a rope having its two ends (14) secured to a keeper bar (16), turned to twist the rope ends and secured by inserting its end in a loop (18) on the associated seam. As a further modification, two endless ropes 6 &c. may be inserted in each seam. |
