Patent GB-1204886-A (GB)
Title: Improved fastening device
IPC: B44C7/02
Filed: 1967-09-12
Abstract: 1,204,886. Securing carpets to floors. AMERICAN VELCRO Inc. 12 Sept., 1967 [7 Oct., 1966], No. 16706/67. Heading A4S. [Also in Division E2] A separable fastening device comprises first and second tape members each having a base and hooking elements formed of a flexible resilient material the elements of one member being loops and the other hooks characterized by the property that pressing the base supporting the hooks into face-to-face relationship with the base supporting the loops will result in a large number of hooks interengaging a large number of loops to resist separation but are readily separable by applying a force in a direction to open the hooks, and the improvement comprising a resilient plastics strip having an arched crosssection bonded to one of the tape member bases, or respective said strips bonded to both tape member bases, the or each strip being bonded at its convex surface to the underside of the tape member base such that physical attachment of the strip to a flat surface by anchoring means extending through the strip and into the flat surface will cause the strip to flatten without bowing at its longitudinal edges, such that the convex surface is flattened to a planar surface the hooks or loops substantially covering said top surface. In the construction shown in Fig. 3, the base 28 from which the hooks or loops extend is made of fabric and the hooks or loops are formed by raised threads 29; the plastics strip 21 is provided with longitudinally extending ridges 26 which define a channel into which the tape member is fastened by adhesive. The ridges help to keep the plastics strip flat when secured to a flat surface. One use of the device described is for securing a panel to a wall, one part of the device consisting of the tape member and plastics strip being secured to the wall and the other part consisting of the other tape member and plastics strip being secured to the panel by fastening means through each part along its centre line, the panel being pressed against the wall so that the hooks engage with the loops. Another use described is securing a carpet to a floor one part being secured to the edge portion of the carpet and the other part being secured to the floor. A further use is for securing covers to motor vehicles. For both carpets and motor vehicle covers the part secured to the carpet or cover consists of the tape member only without the resilient strip. When two parts both with resilient strips are used the parts are separated when it is required to release the device by a letter opener type device inserted between the two bases. When only one part has a plastics strip, the parts can be separated by peeling the part which consists of the tape member only, from the other part. The part consisting of a said tape member and a said plastics strip is made by a method which comprises extruding the plastics strip from an extruder 19 through a die 20 so that the extruded strip has the arched cross-section, the extruded strip is then cooled by advancing it through 20 feet of cool air from an air blower 22 so shrinking and hardening the strip and after this the tape member 10 the underside of the base of which has been coated with a thermoplastic adhesive is attached to the strip 21. The tape member is advanced from a storage spool not shown into a retaining bin which holds a sufficient amount of the tape member to allow an operator time to skive and join the end of one tape member of one storage spool to the leading end of the tape member of another storage spool to allow continuous operation. From the storage bin the tape member passes over a roller 12 and enters a trough 14 which is disposed below infra-red lamps 15; the under surface of the tape member which has been pre-coated with the adhesive faces the lamps 15 to activate the adhesive. The tape then passes over rollers 13 and 16 and the tape member and the strip 21 pass together through rolls 17 and 18 where the tape member is bonded to the strip. The surface of the pressure roll 17 is concave and the surface of the pressure roll 18 is convex so that the curvature of the strip 21 is maintained. As described the strip 21 is made of vinyl, the base of the tape member is nylon and the adhesive is a synthetic rubber resin solvent type adhesive containing 20-28% by weight of solids, the solids comprise 40-60% by weight butadiene-acrylonitrilecopolymer rubber and 60-40% by weight of a vinyl resin which is a copolymer of vinylchloride and vinyl-acetate. The solvent comprises a 50% mixture of acetone and methyl-ethyl-ketone. The hooks or loops can be made of a synthetic resin material which is interwoven with the base but other materials can be substituted for the base and the hooks or loops, for example threads of fine wire, or the hooks or loops could be made by some method other than weaving such as casting.