| 摘要 |
624,255. Batteries. NATIONAL LEAD CO. June 19, 1947, Nos. 16197 and 16198. Convention dates, Oct. 19, 1940. [Class 53] [Also in Group XIII] Accumulator negative plates pasted with a mixture of litharge and finely divided lead are dried in air, the oxidation of the lead providing the necessary heat. The surface moisture on the plates is first removed by the application of heat or by absorption in a porous material and the plates are then stacked one upon another. If surface moisture is not removed, the plates must be separated from one another during the drying operation to prevent sticking. To provide sufficient heat by the oxidation of the lead, this must be present to the extent of five to fifty-five per cent of the mixture. Positive plates also contain red lead. To dry the surfaces of the plates preparatory to stacking, they may be heated electrically or the plates may be pickled in sulphuric acid or ammonium persulphate solution or treated with carbon dioxide. Alternatively, the final scrapers of the pasting machine may be heated or the pasted plates may be conveyed from the machine on heated belts or the plates passed between heated rollers. Other methods comprise pressing, squeezing or rolling or the application of absorbent material to the surfaces of the plates. The Figure shows an apparatus for drying the surfaces of plates 12a which are suspended by their lugs on a conveyer 33 driven through toothed wheels 34. The plates are passed in front of jets 36, 37, 38 through which hot air is pumped. The conveyer is cooled in a water tank 44. |
