| 摘要 |
<p>721,592. Filters. STEVENS, R. J. Feb. 11, 1952. [March 29, 1951] No. 7301/51. Class 46. [Also in Groups XVI, XXVIII and XXXVI] A filter of the type comprising a pack of metallic laminae or a coiled metal sheet in which one or both of each pair of contacting faces has been either chemically etched or electrolytically treated, with the aid of an insulated masking pattern (afterwards'removed) to form depressions or projections and, in consequence, fine flow passages, is characterised by the provision of inflow lanes and outflow lanes across the interfaces of the layers of the pack or coil to give access to and from the flow passages. One face of a length of sheet metal, Fig. 4, has flow passages comprising grooves which may take any of the forms I to L. Grooves Mare joined by passages m extending lengthwise. Alternatively there may be provided raised dots O or ribs P between which flow takes place, or grooves P. The sheet is rolled upon itself to form adjacent layers E. F, G, Fig. 1, with flow passages H. In such a coil or pack there are provided inflow and outflow lanes R, Fig. 2, which, as here shown, extend depthwise through the individual layers. The layer A has inflow lanes only, aligned with the inflow lanes of the layers beneath, while the layer G has outflow lanes only, aligned with the outflow lanes above, the liquid flowing in parallel between layers. Where equal numbers of lanes are provided in all layers and the lanes are staggered, series flow results. These two forms may be combined. The coil, Fig. 1, may be housed in a frame comprising semi-circular members 1, 2, Fig. 5, bolted together at 3, the coil being supported against the flow by grille 5. A cylindrical pack may be formed of superimposed discs, Fig. 7, each having a set of inflow lanes S and outflow lanes T, aligned as in Fig. 2, the uppermost and lowermost layers (not shown) having inflow lanes only, and outflow lanes only, respectively. The masking pattern may be printers' ink, e.g. that used for the preparation of etched metallic labels and may be applied by printing-block or roller or lithographically or photographically, preferably to a large sheet which may be cut up into sections. Each filter layer may alternatively consist of a thin film of metal applied, by evaporation or otherwise, to the surface of a non-metallic carrier sheet, the thin film having been etched &c. subsequently to its application to the carrier sheet. Where the sheet is wholly metal the size of the flow passages may be reduced by rolling ; alternatively or additionally, metal may be electro-deposited on the sheet for this purpose.</p> |
