Lubricating oil filtering device

Claim 1

In an oil filter, an outer casing formed with an inlet through which oil to be filtered enters said casing, a pair of concentric perforated cylinders in said casing, said cylinders having different diameters and defining between themselves an elongated annular space, filter means situated in said casing in the path of flow of oil from said inlet through one of said cylinders to said annular space for filtering the oil prior to the time when the oil reaches said annular space, said cylinders and the common axis thereof being upright during use of the filter, and outlet means for discharging oil from said casing, said outlet means communicating through the other of said perforated cylinders with said annular space at a predetermined elevation along the common axis of said cylinders, and ring-shaped magnet means situated in said annular space at said predetermined elevation therein for acting magnetically on particles in oil flowing to said outlet means through the other of said cylinders, whereby particles remaining in the oil in said annular space flowing toward said outlet means which respond to magnetism will be retained by said magnet means before reaching said outlet means, said cylinders including inner and outer cylinders respectively having outer and inner surfaces between which said annular space is defined, said filter means surrounding said outer cylinder and said outlet means communicating with the interior of said inner cylinder, said ring-shaped magnet means including an intermediate magnetic ring and a pair of magnetic end plates respectively engaging upper and lower end surfaces of said ring and projecting radially beyond the inner and outer peripheries of said ring to define a pair of circumferential channels respectively directed toward the inner and outer surfaces of said outer and inner cylinders.