| 摘要 |
<p>An apparatus and method for manufacturing flexible duct comprising feeding a strip of cloth end a channel formed strip of watel in parallel through a work station having a pair of crimping rollers which fascan an edge of the fabric into the channel. A forming ring is provided at the work station to guide a first coil of fabric attached to channel strip around to meeet and overlap a second coil of fabric being fed into the work station. A roller member is rotatably fixed above the work station to force the overlapping edges of adjacent coils of fabric down into the causel of the metal strip being simultaneously fed in parallel with the fabric toward the crimping rolls. The roller member carries with it a string which it inserts into the channel over the overlapping edges of the fabric prior to the combined materials being fed into crimping rollers where they are forced into a retained and fixed position within the enfolded arms of the crimped channel of metal. The string provides a filler to bulk up the interior of the channel cavity to prevent the overlapping edges being pulled out of the same provided by the closed channel of metal strip.</p> |
