| 摘要 |
Apparatus in which glue is applied to an endless thread by running the thread successively through the bore of a nozzle needle and a nozzle aperture and, when the nozzle needle is retracted from a valve seat, coating the thread with glue which has been forced out of a surrounding chamber. The thread, together with this coating, passes through the nozzle bore. As soon as the nozzle needle is advanced up against the valve seat in the nozzle element, the glue feed ceases and coating ends, so that the thread takes with it at most only very small quantities of glue remaining in the nozzle bore and an exact cutoff of the glue coating is obtained. When the glue is injected around the thread, that is, when the glue is brought together with the thread under a specific pressure exerted on all sides, it is possible to obtain a substantially uniform coating of the thread surface with glue which allows all improved bonding of the thread over its length to the sheet-like structure.
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