GB808504A - Improvements relating to fastening devices - Google Patents

Abstract

808,504. Releasable fastenings: wood screws. EVERED & CO. Ltd. Sept. 17, 1956 [Sept. 17, 1955], No. 26665/55. Classes 44 and 89(2) A fastening device comprises separable components which are adapted to be attached to respective members required to be retained in a position of assembly or closure, one of the components 10 being a female component having a sleeve portion 12 made of elastically deformable natural or synthetic resin and the bore 15 of which sleeve portion converges slightly in a direction axially from its forward end, and the other component being a male component 20 having a portion 23 of greater rigidity than the sleeve portion, the two portions having dimensions such as to engage each other with an interference fit providing resistance which slightly increases and decreases as the male portion moves along the sleeve portion inwardly and outwardly thereof respectively, and includes an air venting arrangement to permit egress and ingress of air from and to the rear of the sleeve portion in an unrestricted manner during inward and outward movement respectively of the male portion relative to the sleeve portion. As shown, the rear end of the sleeve is closed and the square cross-sectional shape of the bore 15 provides four air venting channels round the spherically shaped male portion 23. Alternatively, the bore 15 may be circular and an air venting hole provided in the end wall of the sleeve, or the rear end of the latter may be open and the bore or the male component provided with grooves or channels. The female component 10 is formed as a one-piece moulding and the male component 20 which may be of metal, is adapted to be screwed into one of the two parts to be fastened together. Alternatively the male component may be moulded from a synthetic resin which sets to a relatively rigid form in which case the screw thread is replaced by a plate portion.