| 摘要 |
<p>1477570 Air filters FLANDERS FILTERS INC 28 Nov 1975 [5 Dec 1974] 49101/75 Heading B1T [Also in Divisions F2 and F4] An air filter element 49 capable of removing sub-micron sized particles has combined therewith a rectangular frame member 47 in which it is sealably disposed, the opening through the frame being closed, suitably on the downstream side of the filter element, by valve means 60 comprising a pair of rectangular plates of a size conforming to the outline of the frame and each having numerous apertures 56 therethrough, the apertures being distributed over the entire surface of the plates and corresponding in position and number on each plate, the plates being mounted for sliding movement relative each other so that the apertures in each may be brought into alignment to open the valve or taken out of alignment to close the valve and a film of non-evaporating viscous fluid, e.g. petrolatum or silicone grease, being interposed between opposing faces of the plates to prevent lateral flow of air between the plates. The filter elements may comprise pleated sheets of glass, ceramic or cellulose-asbestos. The frames 47 may be wood or pressed chipboard. A plurality of the filter element/frame/valve units may be mounted in parallel in channel members 41, the channels being partially filled with a fluid to form a seal. A clean room is described comprising a false ceiling formed from a bank of the filter element/valve units mounted in the channel members 41, the channel members being sealed to the room walls at the periphery of the filter bank. The space above the false ceiling provides an inlet plenum for gas to be filtered fed in via a blower from a bank of coarse pre-filters mounted behind a wall of the room and filtering air circulating from grills in the room floor. The valve means for each filter element are arranged to be individually operatable from within the room.</p> |
