| 摘要 |
In manufacturing a continuous slide fastener stringer, a plastic wire is coiled into a helix abut a fixed mandrel, and the helix is withdrawn from the mandrel while its convolutions are braked on one side so that the helix is distorted. It is thereafter shaped on a heated spacing wheel, and each convolution is deformed by a toothed kinking disc. The stringer so formed has convolutions of periodically varying inclination and has alternating parallel shanks connected by inclined portions retaining the original coiling pitch and having protuberances which secure loops of sewing threads by means of which the stringer is attached to a supporting tape.
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