GB1280357A - Multi-density screw-on throw away type filter - Google Patents

Abstract

1280357 Disposible integral housing oil filter WIX CORP 30 June 1969 32950/69 Heading BID A disposable filter cartridge adapted to screw on to an I.C. engine to filter the lubricating oil comprises a cylindrical housing with a central threaded outlet socket 24 at one end surrounded by inlet apertures 22, which cooperate with non-return anti-drain valve 26, and enclosing an outer filter element 30 and an inner filter element 32, separated and reinforced by foraminous corrugated tube 52. The elements 30, 32 operate in parallel in Fig. 2 and both are by passed when clogging raises the differential pressure enough to open valve 62. In Fig. 7 (not shown) a small orifice (102) limits the flow to the inner filter element and in Fig. 8 (not shown) a further valve at the top of the housing prevents oil from reaching the upstream side of the inner element until the pressure drop across the outer element is sufficient to open the valve. Figs. 10, 11 (not shown) illustrate a combined by-pass and antidrain valve in a cartridge similar to Fig. 2. Fig. 12 (not shown) illustrates a cartridge with a left-hand threaded nut on its closed end, which enables a spanner to be used to unscrew the cartridge from the engine but not to tighten it. Fig. 12 also differs from other embodiments in that the elements act in series and apertures (194) of variable size allow some of the flow to by-pass the outer element. In general outer element 30 is of pleated paper and inner element 32 is moulded and rigid, but this arrangement could be reversed or both could be paper or moulded. Their porosities might be equal or different.