| 摘要 |
<p>1,237,330. Making bags. DOW CHEMICAL CO. 19 Dec., 1969, No. 62035/69. Heading B5D. [Also in Divisions B8 and E2] In the manufacture of flexible bags having releasable strip fastener closures, a continuous tube of material 12 provided with complementary strip fastening members 14, 16 (not shown) extending longitudinally of the tube is passed over a generally rectangular mandrel comprising means, preferably grooves, to align the fastening members, an arm 44 mounting a blade 46 for parting the tube between the fastening members, and nip rollers 64, 66 to engage the,fastening elements. The blade 46 may be offset from the centre line of the mandrel or the tube may be guided to the blade such that the two parted edges may be of unequal length. After passing through the rollers 64, 66 the tube is intermittently sealed and severed in a transverse direction to complete the bags.</p> |
