Apparatus for closing slide fastener chains having sliders

An apparatus for closing a pair of slide fastener stringers including a plurality of longitudinally spaced chains of partly engaged coupling elements with sliders mounted respectively thereon, there being an element-free space between successive chains, each chain having a disengaged portion extending between a top end thereof and the slider mounted thereon, said apparatus comprising:

• (a) a stationary element-engaging block disposed on one side of a path of movement of the coupling element chains and having a first guide groove facing toward the path;
• (b) a movable element-engaging block disposed on the other side of the path and having a second guide groove facing toward said first guide groove, said movable element-engaging block being reciprocative toward and away from the stationary element-engaging block for causing said first and second guide grooves to selectively form a guide channel for constrictingly receiving therein the disengaged portion of each chain to close the same;
• (c) a sensor disposed upstream of said stationary element-engaging block for detecting the element-free space and the slider mounted on the chain next following the element-space;
• and
• (d) an actuator under the control of said sensor and operatively connected to said movable element-engaging block for reciprocating the latter.