| 摘要 |
993,184. Filters; filtering systems. M. BOHLER, and F. WEBER, [trading as BOHLER & WEBER KOMM.-GES.]. Oct. 22, 1962 [Oct. 27, 1961], No. 39940/62. Heading B1D. In a process for filtering solvent in chemical cleaning machines, filter powder is added from pin trap 2, Fig. 2, to solvent from cleaning drum 1, in a single quantity sufficient for filtering several charges of solvent to filter casing 6. The filter powder is floated afresh on to filter elements in 6 at the start of each charge, and the accumulated cake is removed therefrom, by means operable from outside the casing, at the end of each charging operation without removal from the filter casing. Solvent, moved by pump 4, may be recycled to the filter casing via pipes 7 and 8. A preferred filter apparatus comprises a casing having conical bottom 12, Fig. 1, and a plate 13 with filter elements 15 connected thereto under tension. A domed cover 14 forms hollow space 20 for filtered solvent, discharging through pipe 21. Solvent enters pipe 16, which has one outlet 18 at the end of riser pipe 17, and another outlet 19 directed downwardly in such a manner that the solvent may impinge against the conical base of the casing. Preferably, outlet 19 is is placed off-centre and skew of the longitudinal axis of the casing. Sedimented filter powder is thus swirled upwardly, and light particles, e.g. fluff, are swirled downwardly, so that an even deposit on the filter elements is obtained. Outlets 18 and 19 may be provided with nozzles to subdivide the flow. Filter elements 15 are coiled springs. Filter cake is removed from the elements by means of pusher rods 22, extending inside the elements. When the rods 22 connected by yoke 23 are pushed downwards by actuator 25, the apertures between the coils of the springs are enlarged, causing the cake to fall away to the bottom of the casing. Alternatively, compressed air or back-flushing may be used to remove the cake. Sludge is removed, e.g. at the end of each day's working, by outlet 26. |
