Abstract: A process for manufacturing zip fasteners by molding sets of locking members of any length and of the staggered or slit type, the upper stop members, the coupling and the box, in a single operation. The process is achieved with a two-part injection molding tool having strips with recesses for forming locking members which are applied to both the lower and the upper part of the tool. The lower strips can be moved vertically. A transverse slide has recesses for the upper stop members, a recess for the coupling, and a mold part for a box, in which is located a mold body displaceable within the plane of the slide. In order to form locking members with slits the lower part of the tool is provided with a mechanism which removes the insert forming the slit from the slit when the finished zip fastener member is removed. Accordingly, all combinations of zip fasteners can be manufactured in a single operation without expensive subsequent processing.
Abstract: A process for manufacturing zip fasteners by molding sets of locking members of any length and of the staggered or slit type, the upper stop members, the coupling and the box, in a single operation. The process is achieved with a two-part injection molding tool having strips with recesses for forming locking members which are applied to both the lower and the upper part of the tool. The lower strips can be moved vertically. A transverse slide has recesses for the upper stop members, a recess for the coupling, and a mold part for a box, in which is located a mold body displaceable within the plane of the slide. In order to form locking members with slits the lower part of the tool is provided with a mechanism which removes the insert forming the slit from the slit when the finished zip fastener member is removed. Accordingly, all combinations of zip fasteners can be manufactured in a single operation without expensive subsequent processing.