GB702168A - Improvements in filters - Google Patents

Abstract

702,168. Filters. WIPAC, FILTRATION, Ltd. May 16, 1952 [May 25, 1951], No. 12351/51. Addition to 639,289. Class 46. [Also in Group XXVI] The filter of the parent Specification is modified for full flow filtration, e.g. of lubricating oil in an internal combustion engine, by making the bore leading through the spigot of large enough flow area for such flow and by arranging at least three return or flow ducts around the bore, the ducts having a combined flow area at least equal to that of the bore. A triangular base plate 1 has 'a tubular boss 2 integral with it in which a socket 6 is provided as in the parent Specification. Annular grooves 9 and 5, in the socket and in the lower face of the base plate respectively, communicate by three bores 10 having a total flow area equal to that of a single central bore 4. The latter opens into a screw-threaded bore communicating with the socket 6. A plurality (e.g. ten) ports 17 are drilled in a nut 16 forming part of a canister 12a, these ports communicating with the groove 9 and with the space above it between an annular washer 11 and the spigot 14 projecting from the canister when the canister is in position on the base plate. The total flow area of the ports 17 is equal to that of the bore in the spigot. The spigot 14 is secured by engagement of part of its screw-threaded portion in a nut 15 soldered inside a pressing 12, and in the nut 16 which is first screwed on to the spigot 14 to lock it in position and is then soldered to the pressing 12. An unthreaded portion of the spigot 14 protrudes beyond the nut 15 to accommodate a sealing ring 22 against which a filter element 21 is pressed by a spring 24. When fitted to a motor cycle the support 1 is fitted in a recess on the oil tank, the bores 10 discharge directly into it above the oil level, and the oil return pipe from the engine sump communicates with the bore 4. A spring-loaded ball valve may be arranged in a duct in the support interconnecting the central bore with one of the circular grooves 5 and 9. According to the Provisional Specification the filter element comprises an axiallyplated tube of resin-impregnated paper surrounding a perforated tube of zinc or the like, the relief valve may be replaced by a valve in the canister constituted by a rubber sleeve fitted over a part of a central inlet tube of the canister, having an aperture formed in the wall. The Complete Specification refers to the parent case.