LUBRICATING AGENT COMPOSITION AND REDUCTION GEAR USING THE COMPOSITION, AND MOTOR DRIVE POWER STEERING DEVICE USING THE REDUCTION GEAR

摘要

A lubricating agent composition which comprises a lubricating base oil, fine particles and a calcium sulfonate based thickener; a reduction gear using the lubricating agent composition; and a motor drive power steering having the reduction gear. The motor drive power steering can reduce the noise from the reduction gear due to the effect of the fine particles, while preventing the separation of an oil due to the effect of the calcium sulfonate based thickener added in the lubricating agent composition, independently from the degree of the backlash in the case of the combination of a small gear and a large gear, and without the use of a reduction gear having a complicated structure, which results in the decrease of the noise in the compartment originating from the motor drive power steering with a reduced cost.