| 摘要 |
583,191. Moulding battery separators. UNITED STATES RUBBER CO. May 10, 1944, No. 8904. Convention date, Sept. 11, 1943. [Class 87 (ii)] [Also in Group XXXVI] Storage battery separators having discontinuous raised ribs are made by pressing a sheet of microporous vulcanized hard rubber or other plastic composition between dies 17, 18. The rubber sheet is first softened in hot water and the dies are maintained in a heated condition by electric heating elements 19. The dies are cooled before the embossed sheet is removed. If the plastic material of which the separators are made has a softening temperature above the boiling point of water it is immersed before the pressing operation in glycerine, butyl alcohol or other liquid having a high boiling point. Instead of using a sheet of plastic material between the dies the separator may be made by a moulding operation in which a powder capable of forming a microporous material when heated is introduced between the dies. In a modification the sheet is passed between rotating heated rolls formed with ribs and depressions, or an extruding operation may be used. Long lengths of plastic material may be wound on a drum with a liner cloth and vulcanized and then subjected to the rib-forming operation, the embossed strip being finally cut to the required size to form the separators. Specification 532,475 is referred to. |
