Double-filtering filter for vehicle engine lubricants, with compressible fine filtering cartridge

摘要

An oil filter for providing coarse and fine filtration of lubricating oil in an internal combustion engine is disclosed herein. The oil filter includes a cylindrical housing closed by a cover containing a coarse-filtering cartridge of pleated paper included between a lower plate and an upper plate, and a fine-filtering cartridge placed between the coarse-filtering cartridge and the cover. The fine-filtering cartridge is supported between a lower base plate and an upper base plate arranged to bear against the cover. Both filtering cartridges have a cylindrical shape with axial recesses extending therethrough. The fine-filtering cartridge is composed of a band of filtering paper disks, the band being bent as an accordion. The upper base plate is integrally formed with to a first end of a barrel with the barrel coaxially extending through the axial recess of said fine-filtering cartridge and partially into the axial recess of said coarse-filtering cartridge. The filter includes means for fixedly attaching the upper plate of the coarse-filtering cartridge about said barrel, with the lower base plate being slidably attached about the barrel. A helical compensating spring is placed between the upper plate of the coarse-filtering cartridge and the lower base plate of the fine-filtering cartridge for compressingly stressing the fine-filtering cartridge towards said housing cover.