GB909641A - Improvements in the manufacture of sliding clasp fasteners - Google Patents

Abstract

909,641. Sliding-clasp fasteners. PLATE, K., and WAHL, N. A., [trading as PATENTGESELLSCHAFT PLATE & CO.]. July 31, 1959 [Aug. 7, 1958], No. 26401/59. Class 44. [Also in Groups V and IX] A row of fastener elements for a sliding clasp fastener is in the form of a spiral filament or wire having transversely extending loops, each loop comprising a head 7, two arms 2 and a base portion 3 connecting adjacent loops, of polyamide, polyurethane or polyester, for example, the head which forms an engaging portion extending perpendicularly or approximately perpendicularly to the plane of the fastener; the arms 2 of each loop overlap one another as viewed in projection on to the plane of the fastener and the head 7 of each loop is broadened at the point of engagement so as to extend on both sides of the loop almost over the entire length of the loop head 7, and the arms 2 of each loop are near to each other at the base portion 3 so that both arms of the loop can be secured on one side of a stringer tape with the base portion 3 extending almost parallel to the plane of the fastener. The elements may be unsymmetrical, Fig. 7 (not shown), or the arms 2 thereof may be inclined to an axis of symmetry of the fastener, Fig. 8 (not shown). In another embodiment, Fig. 10 (not shown), the arms 2 are formed with enlargements which extend in the longitudinal direction of the fastener, the adjacent enlargements abutting to maintain accurate spacing of the elements. The row of elements may be stitched to the stringer tape, Figs. 12, 13 and 14 (not shown), and the arms 2 may have indentations therein in which lies the sewing thread securing the row to the stringer tape, Fig. 6 (not shown). The row of elements is preferably made by continuously feeding the filament or wire 18, Fig. 15, through a hole 19 in a guide 21, the latter being associated with a shaping gear-wheel 24 and reciprocating in the direction of the arrow 20 to guide the wire through a gap 22 in the wheel 24 to thereby form an arm 2 of one of the elements. A shaping pin 27 which is movable in the directions of arrows 25 and 26 is then moved in co-operation with the guide 21 so as to form the head 7 of the element, a flat being simultaneously formed on the head by a punch 30 on the guide 21. The gear-wheel is thereafter advanced by one tooth to allow the next element of the row to be formed. The row of elements on the wheel 24 travels through a heating zone on the circumference of the wheel and after cooling is preferably united with a co-operating row of elements.