| 摘要 |
<p>966,980. Filters for liquids. PALL CORPORATION. Dec. 20, 1960 [Feb. 2, 1960], No. 43693/60. Heading BID. [Also in Division F2] A filter by-pass valve, which opens to allow flow in the event of clogging of the filter, comprises an assembly 53, Fig. 5, screwed on to the inner end of an outlet 52. The assembly comprises a bowed spring disc valve 60, which may be a Belleville washer, supported by its outer periphery on a ledge 62 and normally engaging a seat 61. In the event of the filter becoming clogged, the inlet pressure in a passage 58 causes the disc to flex to allow flow to the outlet 52. The valve is primarily designed for flow in the direction shown, i.e. from inlet 51 to outlet 52 although flow may take place in the opposite direction when the pressure in a space 66 below the valve disc causes the outer periphery of the disc to flex when the filter becomes clogged. However the space 66 may itself become plugged and when flow is required in both directions the valve shown in Fig. 6 is preferably used. In this case, the housing part 63 is tapered below the disc instead of being right angled, and prongs 70 are provided to limit the movement of tne inner periphery of the disc. In a further modification the outer periphery of the disc is clamped. The filter element is preferably of the form described in Specification 830,908.</p> |
