GB189916293A - Improvements in the Manufacture of Leaden Plates for Secondary Batteries or Accumulators, and in Moulds and Tools to be Employed in such Manufacture. - Google Patents

Abstract

16,293. Davies, P. J. Aug. 10. Casting; rolling; sawing.-Relates to the manufacture of leaden plates for secondary batteries, especially those known as "Leitner" plates. Fig. 1 shows in section a mould for casting the plates, consisting of two pieces of brass A formed with recesses X, Y, for the thin central portion of the plate and the stout strengthening-edges respectively. To enable the thin plate to be cast successfully, the mould is heated by flames from bunsen burners Q, and perforated pipes may also be fitted through which cold air may be directed upon the mould for cooling purposes. The molten lead enters the mould through channels R, the finished casting being thus surrounded by runners 2, Fig. 4. The runners are subsequently removed by shearing-devices, or by means of circular saws, and the upstanding edges Y', Fig. 6, are turned down so as to form channels round the plate which assist in holding the paste or active material. The finished plate is shown in section in Fig. 5, and in side elevation in Fig. 2. The perforations may be produced either hy punching or by the use of cores in the mould. For the flanges Y<1> may be substituted burred edges produced by passing the plate between suitable rollers. When very thin plates are required, sheet lead may be placed in the mould, and the necessary borders, lugs, &c. may be cast on it, or the plate may be cast in the manner described above and may be subsequently rolled out by rollers having suitable recesses or grooves corresponding with the borders and lugs. The mould is preferably mounted on a casting table such as that described in Specification No. 21,031, A.D. 1890. The perforations shown at U, Fig. 2, are D-shaped holes punched with spurs S, Fig. 7, which assist in retaining the active material. Fig. 8 shows in side elevation an apparatus for removing the runners from the cast plates. It consists of a pair of rotary saws a revolving on opposite sides of a table g on which slides a carriage f to which the casting is clamped. The runners project over the edges of the saws, and are removed as the carriage advances along the table.