| 摘要 |
1,210,029. Forming tubes. ROTHMANS OF PALL MALL CANADA Ltd. 1 Aug., 1969 [19 June, 1969], No. 38793/69. Heading F2P. A continuous band 54, having adhesive material adjacent one edge is formed into a tube by being fed into a continuous belt 48 curled into cylindrical form by curling means, e.g. platens 28-30 (Fig. 5). The band is pressed outwards against the belt, with the opposite edges overlapping and the adhesive sandwiched between them, by compressed gas introduced through holes 60 (Fig. 2, not shown) in tube 58, the loss of gas being limited by bands (62). If heat sensitive adhesive is used the width of the belt is such that its edges 50 do not meet, leaving a gap for heating element 26, which fits into the channel between platens 29 and 30. The overlapping band sections, with the adhesive sandwiched between, are pressed against elements 26, and sealed together, thus forming the tube. Where pressure sensitive adhesive is used, the heating element is dispensed with, platens 29 and 30 are replaced by platen 66 (Fig. 6, not shown) and belt 48 has sufficient width to form a complete cylinder. |
