Patent GB-742421-A (GB)
Title: Improvements in or relating to sliding clasp fasteners
IPC: A44B19/28
Filed: 1953-06-22
Abstract: 742,421. Sliding-clasp fasteners. DESHAW, Z. April 21, 1954 [June 22, 1953], No. 17301/53. Class 44. A slider for a sliding-clasp fastener comprises a member for operating the slider and two slider shields for guiding fastener stringers through the slider, the slider shields being formed so as to allow spreading apart of the shields for separating the stringers from each other when the slider has jammed, one of the slider shields having a riser element extending through a slot in the other slider shield, the shields being releasably locked against unintentional spreading during normal operation of the slider by a catch slidably arranged between a platform provided on the riser element and a portion of the riser element which overhangs the platform, the catch normally engaging with one end portion of the slotted slider shield. As shown, the slider comprises two opposed shields 1 and 12, a pull tab 22 and a spring- loaded catch 60. The shield 1 comprises a base 2 having side walls 3 and 31, the wall 3 extending for only a part of the length of the base, a riser element 4 integral with the base and a platform 8 spaced from the base substantially by the width of interlocking fastener elements. The riser 4 is formed with a recess for a spring 70 of the catch 60, and a groove 6 for a hinge pin 17 of the shield 12. The latter is formed with a central slot 13 and with side walls 14 and 141 adapted to overlie the walls 3 and 31 of the shield 1 and also with recesses 18 and 181 to receive the longitudinal edges of the platform 8. In the normal locked position, the pin 17 is located in the groove 6, the end 11 of the riser 4 being turned over to retain the pin. The catch 60 and the riser 4 extend through the slot 13 with the catch bearing on the platform 8 and with the nose of the catch flush with an overhanging portion 9 of the riser and with a shoulder 64 on the catch engaging a base portion 16 of the shield 12. The pull tab 22 is pivoted in a bearing hole 7 in the riser. In order to hinge the shields apart the catch 60 is pressed inwardly against the spring 70 until the nose of the catch releases the base portion 16. In this position the walls 31 and 141 lie behind the interlocking fastener members attached to one stringer tape so that this tape is held between the riser 4 and the side walls 31, 141, while the fastener members attached to the other tape may be laterally detached from the slider by virtue of the shorter walls 3 and 14. A recess 52 in the riser accomodates portions of the fastener members retained by the walls 31, 141 of the slider. The base 2 of the shield 1 is provided with a chamfer 50 to avoid any tendency for these members to be nipped between the slider shields in the released position thereof. The slider is closed by merely pressing the shields together. In modifications, the walls at each side of the slider may both be of the same length as the walls 3, 14 and the recess dispensed with, to permit complete separation of the slider from the fastener members. The catch may be of any other suitable form. Specification 736,622 is referred to in the Provisional Specification.