GB577510A - Improvements in or relating to oil filters - Google Patents

Abstract

577,510. Oil filters. AC-SPHINX SPARKING PLUG CO., Ltd., BROWNE, D. B., and BUCKMAN, K. E. May 23, 1944, Nos. 9965, 10420 and 17714. [Class 46] An oil filter comprises a casing for enclosing either of two types of tubular filter element which fits around a central tube provided with an orifice, each type of element having a cap or the like associated therewith, the arrangement being such that when one type is fitted in the casing all the oil passes through the filter element, and when the other type is fitted, part of the oil passes through the filter element and part passes through the orifice unfiltered. In the construction shown in Fig. 1, in which the left-hand half section illustrates a " fullflow " filter element through which all the oil circulates, and the right-hand half section illustrates a " partial-flow " element through which partial flow of the oil takes place, a casing 1 is provided with an inlet 2 for oil and an outlet 3 leading to the bearings of an internal combustion engine. Passages 2 and 3 are connected by passage 4 provided with a spring-pressed valve so that unfiltered oil passes to the bearings if the oil pressure becomes excessive. The passage 3 communicates with a tube 7 provided with orifices 8. In the case of the " full-flow " filter the cap 15 fits around the tube 7 above the orifices 8, so that oil passing into the casing through tube 6 flows through the filter and then through the orifices 8 and passage 3 to the bearings. Part of the filtered oil flows through a tube 11 with restricted orifice to the crankcase. In the case of the " partial-flow filter the cap 16 fits around the tube 7 below the orifices 8 so that most of the oil can flow unfiltered to the bearings. A small proportion passes through the filter and through tube 11 to the crankcase. In a modification the pressure-relief valve is provided on the cap 15 of the " full-flow " filter, the spring seating of the cap being apertured and the apertures being normally closed by a spring-pressed disc underneath. In afurthermodification shown in Figs. 3 and 4, the cap 15 is formed with orifices 22 closed normally by resilient strips 21, the ends of which engage inwardly-pressed parts 23 of the cap. Excessive pressure of the oil forces the strips away from the orifices 22. The arrangement may be modified by the provision of the strips on the outside of the cap in which case the oil flows from the inside of the element outwardly. In the arrangement shown in Fig. 5 which is a composite section showing a half of a " full-flow " filter and a half of a " partial-flow " filter, the " full-flow " filter has a relief valve arrangement comprising two resilient strips 21 and a sleeve 26, the upper end of the sleeve slidably fitting on a boss 25 on the cover 10 and the lower end being secured to the sleeve 14 of the filter element. A flanged ring 27 transmits pressure between the filter element and the spring 17.