GB556304A - Improvements in or relating to engine oil filtration - Google Patents

Abstract

556,304. Filters; lubricating systems. LE CLAIR, C. C. S., and TECALEMIT, Ltd. Jan. 24, 1942, No. 1021. [Class 46] [Also in Group XXXIV] In an oil filtration system, particularly a force-feed lubricating system for I.C. engines, oil is fed by a pump 25, Fig. 1, from an intake 24 in a sump &c. through a pipe 26 to a filter 1 and passes through the filter element 4 and an outlet 12 to a pipe 36 leading to the bearings until the designed pressure is reached and a spring-pressed piston valve 15 operating in accordance with the pressure connects a pipe 23 in the filter 1 with a pipe 27 for recirculating surplus unfiltered oil. The pressure exerted by a spring-pressed valve 32 in the pipe 27 causes some of the relieved oil to flow through an orifice 34 and a pipe 35 to a part of the sump remote from the intake 24. At starting, oil is repeatedly circulated and quickly heated by the heat produced in the pump, only a small amount passing through the pipe 35. As the temperature of the oil rises, more or all of the excess oil passes through the pipe 35 and heats the oil in the sump. An auxiliary filter 47, Fig. 2, may be associated with a main filter 38. Oil is fed by a pump 56 from an intake 57 through pipes 58, 63 and a three-way valve 59 to the filter 38 and passes through the filter element 39, outlet 43 and pipes 81, 82 to the bearings until a spring-pressed piston valve 73 operates to connect a secondary outlet 45 with a pipe 67 for recirculating surplus oil. Oil supplied to pipes 83, 93, being, when cold, at a greater pressure than that in a pipe 95 opertes a spring-pressed piston valve 88 to connect the pipe 83 with the inlet 52 of the filter 47, the filtered oil passing through a pipe 94 to the bearings and the surplus oil through a pipe 97 to the inlet of the valve 77. The pressure difference decreases as the oil is heated and the valve 88 operates to cut off the supply to the filter 47 and the non-return valves 53, 55 close. When the resistance of the main filter rises to a predetermined value, the auxiliary filter automatically comes into operation. By turning the valve 59 through 90 degrees clockwise, or anti-clockwise, the filter 47, of the filter 38, may be isolated for cleaning. The filter 38 may be used alone, the filter 47 with the pipes 94, 97 being removed and the pipe 63 connected by a pipe 58a to the pump. Two or more main and auxiliary filters may be provided in a single casing. The Provisional Specification comprises also slightly modified forms of the control valves 73, 88. In the valve for the main filter the piston rod passes through a hole in a perforation diaphragm, on which the spring bears, and in the valve for the auxiliary filter, the diaphragm is imperforate and the space above it is connected to the pipe leading to the bearings.