| 摘要 |
837,420. Seaming non-metallic sheet materials. ARMELIN, E. R., and PLASKETT, A. F. G. Feb. 6, 1957 [Feb. 6, 1956], No. 3691/56. Class 42 (1). Apparatus for transversely seaming superposed portions of a single folded sheet of a thermoplastic material comprises two chains or belts 1 and 2, pairs of sealing members 12 and 13 mounted transversely to the direction of movement one on each of the chains so that they press against each other over part of their paths, an electrically-heated chamber 14 for heating the sealing members 12 and grippers 17 which are fixed to the chain 2 and which grip the leading portion of a blank of sheet material 33. The sprocket-wheel 22 has a cam which engages the grippers to open them as they come into contact with the wheel in order to release the blank into the box 38 and to close them as they leave the wheel in order to grip a blank fed to the apparatus over rollers 37 after being cut by a rotating knife. 34. The blank is folded before sealing by an arm 29 co-operating with an arm 26 which is fixed to the sealing members 13 and is operated by a cam 28. The grippers 17 may be mounted on a separate chain so that they are adjustable relative to the heating members. The sealing members 13 may also be heated or may be cooled, and one of the chains may be replaced by a roller. Specification 837,421 is referred to. |
