| 摘要 |
An improved system for directing a web of flexible material to a predetermined location, and more particularly, a system for directing the end or tail of a moving web into threading engagement with rolls forming a nip or the like. In this system a gas such as air is directed through a restricted opening under pressure whereupon it attaches itself to a flow attachment surface due to the "Coanda effect", so that it entrains ambient air and the moving web tail. In a preferred form of the system, after the web tail has been entrained and conveyed a predetermined distance, a substantial portion of the combined flow of the entraining gas and the entrained ambient air are diverted off toward a different direction. At the location of diversion, restraining means is provided for preventing the web tail from moving with such substantial portion of combined flow. Another aspect of the invention resides in orientation of the restricted opening and flow attachment surface so that the web entrained thereby defines a concave path. Still another aspect resides in utilizing two Coanda nozzles in the system, the first of which is positioned to throw the web to the second across an open space of sufficient magnitude to dissipate a substantial portion of the gaseous flow from said first nozzle so that it does not interfere with operation of the second nozzle.
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