US Patent 7927084 Magnetic trap for ferrous contaminants in lubricant

A compressor is having a tubular vertical shaft, which rotates about its vertical axis, a cylinder block for supporting the tubular vertical shaft, a rotor for driving the rotation of the tubular vertical shaft, and a stator affixed to the cylinder block. Lubricant is channelled from the lower end of the tubular vertical shaft through an inlet of its interior path to the outlet. A magnet is disposed within the interior path to trap ferrous contaminants in the lubricant before the lubricant is distributed to other parts of the compressor.