Month in the Patent Office

A fabric lacing edge, more particularly for securing together the structural fabric parts of a non‐rigid airship, but applicable to other purposes, comprises a folded‐over hem 7 provided with spaced lacing‐holes 8, and rigid inserts 9 which have portions of different thickness and are cemented within the hem with their thick portion bearing against the fold, holes 10 in the inserts being arranged to register with the lacing‐holes 8 in the fabric. The inserts 9 are made of non‐metallic material, preferably plastics, of tapering cross‐section with straight bases which bear against the bottom of the hem, the greatest thickness of the inserts being between their base and the hole 10. In the example the inserts are in the shape of an isosceles triangle diminishing in thickness towards their apex, and are moulded upon a synthetic fabric tape 11 which holds them at the requisite spacing. Nylon or shredded glass fibre reinforced with resin may be used for the inserts, whereas the tape 11 may be of woven fibres of nylon or glass. The opposite portions of the hem 7, enclosing the tape 11 with the inserts 9, are united by neoprene or rubber cement.