| 摘要 |
958,391. Sealing non-metallic sheet material. AGFA A.G. Feb. 20, 1961 [Feb. 20, 1960], No. 6235/61. Addition to 859,554. Heading B5K. [Also in Division B8] The piston of the parent Specification, which directs hot gas into plastic container necks to be welded, is modified by replacing its apertured walls with a series of thin webs 4 which support a concave dish 10. |
