GB557694A - Improvements in or relating to the jointing of flexible sheet material in the construction of flexible containers such as fuel tanks for aircraft - Google Patents

Abstract

557,694. Tanks ; hallow-ware ; sewing. BRITISH UNITED SHOE MACHINERY CO., Ltd., and RICKS, F. April 16, 1942, No. 5020. [Class 69 (i)] [Also in Groups VII and XVII] In the construction of flexible containers, such as fuel tanks for aircraft, joints between sheets of material are formed by the aid of a fillet at the inside surface of the work, the margins of the sheet material being overlapped and sewn together from the outside by a seam which passes through the margins and the fillet but is not exposed at said inside surface. Pieces 1, 3, of material, preferably comprising three layers of fine cambric bonded together with a petrol-resistant synthetic rubber such as Thiokol and having a coating of similar substance at the inner surface 1 b, have their margins overlapped and a preferably substantially triangular fillet 5, preferably of synthetic rubber such as Thiokol with a surface layer 7 and/or internal reinforcement of fabric, is placed adjacent the overlap, petrol-resistant adhesive securing the parts 1, 3, 5 together; a seam 9 of sewing is then inserted. A further strip 11 of Thiokol &c. may be secured by adhesive to the inner surface of the fillet 5 and overlap the edges of the fillet and the piece 3. The outside surface of the joint is then preferably painted with shellac &c. varnish. The container is preferably built up on a collapsable form of wood &c. spars and may be held thereto by a light adhesive. The seam 9 is preferably made by means of a curved hooked needle sewing machine with internal and external work supporting means as in Specification 198,430, [Class 112]. Specification 28331/06, [Class 66], also is referred to.