Patent GB-584108-A (GB)
Title: Improvements in or relating to sliding clasp fasteners
IPC: A44B19/04
Filed: 1945-03-08
Abstract: 584,108. Sliding-clasp fasteners. AERO ZIPP FASTENERS, Ltd., and ENGEL, E. March 8, 1945, No. 5746. [Class 44] [Also in Group XXII] - The fastener members 1 for a sliding-clasp fastener are cut from a strip of metallic or non-metallic material so that the head 9 of each member is formed from the material between the legs 8 of an adjacent member, but so that the ends of the legs remain connected to the rest of the material. The interlocking projections and recesses at 3 may be pressed out before or during the cutting operation. The members are then bent out of the plane of the strip to form an upstanding row of members carried by the marginal portion 5, 6 of the strip material. As shown, the members are at 90‹ to the plane of strip, but they may be bent up to a smaller angle. Preferably, the members are spaced so that the row of members may be applied bodily to the stringer tape and secured thereon, the marginal portions 5, 6 being then removed. If the members, or the interlocking portions 3 are formed singly, the feed of the strip to the cutting or forming tool equals the required pitch between adjacent members. If a plurality of interlocking portions 3 or members 1 is formed or cut simultaneously by a multiple tool, the feed of the strip is a corresponding multiple of the pitch between adjacent members. When the members are bent up to a smaller angle than 90‹ the fastener members are correspondingly inclined to the edge of the tape if the row is applied thereto bodily. When the strip is of metal, the marginal strips 5, 6 provide conductive connections if the members are to be treated electrolytically, for example, if of aluminium they may be anodised by electrolytic treatment and subsequently dyed. In such case, the members may be bent up from the plane of the strip to a small angle sufficient to expose the edges of the members to treatment, for example an angle of 10‹. According to a modification the ends of the legs are left connected at one side only of the centre-line of the strip, the ends of the legs at the other side being free. In this case the members of each row may have a pitch equal to a multiple of the desired final spacing of the members on the tape, and a corresponding plurality of rows may be bodily attached to the tape. For example, if in each row the members are spaced at twice the desired final spacing, two rows may be applied with the members of one row alternating with those of the other. If the members of one row are left connected at one side of the centre line, say by strip 5, and the other row connected at the other side, say by strip 6, the strips can be readily applied with strip 5 of one row at one side of the tape and strip 6 of the other row at the other side. Instead of applying a row bodily the members may be applied to the tape singly, or several at a time and severed, the remainder of the row being suitably displaced after each application to give the required final spacing of the members. More than one row of members may be formed side by' side on a single strip, and the strip may be of thermoplastic material, worked with suitable application of heat and pressure, and the fastener members may be secured to the tape by adhesive.