GB1307672A - Jointing or securing of sheet materials - Google Patents

Abstract

1307672 Seaming non-metallic sheet material GOFFTON Ltd and BUTYL PRODUCTS Ltd 22 April 1970 [1 April 1969] 17008/69 Heading B5K [Also in Division E2] A device for jointing or securing flexible sheet material 18, 19, Fig. 1, comprises two complementary extrusion moulded strips 1, 2 adapted to snap engage, in overlying relationship to retain the sheet material 18, 19, the strip 1 providing a locating strip which is rigid widthwise but flexible lengthwise and having longitudinally extending flanges 4, 7 and the strip 2 providing a retaining strip having longitudinally extending flanges 12, 13 which are resilient widthwise, the flanges 12, 13 being adapted to snap engage between the flanges 4, 7 and, when in such engagement, to be biased towards the flanges 4, 7 to grip the sheet material 18, 19. In one embodiment, Fig. 1, the strips 1, 2 are extrusion moulded from polyvinyl chloride or polypropylene. The strip 1 comprises a base 3 having four flanges 4, 5, 6, 7 having concave faces 4a, 5a, 6a, 7a and chamfered ends 4b, 5b, 6b, 7b, respectively. The strip 2 comprises flanges 12, 13 having concave faces 12a, 13a, heel ribs 14, 15, foot parts 16, 17 and toe ribs 16a, 17a, respectively. In use, the flange 12 snaps into a channel 8 defined by the flanges 4, 5 to retain a flexible plastics sheet 18 and the flange 13 similarly retains a sheet 19 in a channel 9 defined by the flanges 6, 7. The ribs 14, 15 may be provided with longitudinal splines or dimples or batten projections to increase the grip between these ribs and the sheets 18, 19. Side ribs 20 are provided to facilitate removal of the strips 1, 2 by a screw-driver. Ribs 21 may be provided for locating screws to secure the strips 1, 2. In a modification (not shown), the flanges 5, 6 of the strip 1 and the parts 16, 17, 16a, 17a of the strip 2 are omitted. The sheets 18, 19 are retained solely by engagement between the ribs 14, 15 and the flanges 4, 7. In another embodiment, Fig. 3, the strip 1 is provided with two flanges 4, 7 only and the strip 2 is provided with two flanges 12, 13 of dog-leg shape. The device may be used for jointing two edges of flexible sheet material or, as shown, for securing a single flexible sheet 23. In a further embodiment, Fig. 4, the strip 2 is provided with an additional pair of flanges 24, 25, as shown. In a still further embodiment, Fig. 5, the strip 1 comprises two inclined flanges 4, 7 only and the strip 2 comprises a bridging part 26 with two inclined flanges 27, 28 having flanges 29 extending therefrom to overlie the flanges 4, 7. In other embodiments, Figs. 6 and 7, two separate retaining strips 2, 2<SP>1</SP> are provided. In yet another embodiment, Fig. 8 (not shown), the strip (1) is similar to that of Fig. 5 but the strip (2) is extruded in tubular form of roughly triangular cross-section. In a further embodiment, Fig. 9, the strips 1, 2 each comprise two flanges 4, 7 and 34, 35, respectively, to engage as shown.