PURPOSE: To effectively remove an impurity from even an engine oil contg. an additive for preventing initial deterioration, by conducting d.c. between positive and negative electrodes through a lubricating oil to which a formamide component is added.
CONSTITUTION: About 0.5W1.0wt% formamide component is added to an engine oil. After flowing from an inlet 14 into an inside electrode 12 of an electrostatic filter 11, the engine oil flows via a small hole 22 into an oil refining chambers (A), rises through the chamber A, and runs out of each outlet 15. When d.c. is applied, the inside electrode becomes a negative electrode and an outside electrode or a container 12 becomes a positive electrode, forming an electric field in the oil refining chamber A. A negatively charged minute particle in the engine oil is attracted toward the container 12 and attaches to the inner wall of the container 12. Thus an impurity such as sulfur or nitrogen oxide in the engine oil is removed.
MURACHI MIKIO
KATOU AKIRA
