| 摘要 |
1472253 Dry cells C W PUN and C C POON 28 Aug 1974 [29 May 1973] 25461/73 Heading H1B A dry cell comprises a zinc negative electrode, in the form of a tube 1 open at both ends, the length of this tube being substantially the same as that of the depolarizing dolly 7 within the cell, the cell also having a casing of a plastics material comprising a cylindrical sleeve 16 and a bottom 2 which may be integral with the sleeve and a tongue 5 extending from the zinc tube and passing through the casing. The thickness of the zinc tube is defined in terms of a voltage of the cell such that when the cell voltage falls to 0À75 volts, the zinc is substantially consumed. A moulded plastics top 17 is provided to accommodate a carbon anode 4 in the depolarizing dolly and the plastics bottom is provided with a raised portion (8) and teeth (9), Fig. 3a (not shown) to centralize the anode and dolly. An alternative moulded bottom is described, Fig. 6a (not shown) which provides a space for excess electrolyte. In a further embodiment, Fig. 10 (not shown) the tube is not a complete cylinder and has a gap between adjacent longitudinal edges when the cell is assembled. Solid electrolytic paste is preferably used and this is either placed around the dolly and the zinc placed around that, or it is placed on the inside of the zinc cylinder prior to assembly of the cell. |
