Patent ID: 7234368

Claim:
A ball screw device comprising: a ball nut including a bore formed therein and having an inner thread formed therein and defined by a plurality of helical groove portions, and including an orifice formed therein and communicating with said helical groove portions of said ball nut, and said ball nut including a passage formed therein for receiving an oil, a screw shaft rotatably engaged into said bore of said ball nut, and including an outer thread formed thereon and defined by a plurality of helical groove portions, for threading with said inner thread of said ball nut, and for allowing said ball nut to be moved relative to said screw shaft, a plurality of rolling members engaged in said helical groove portions of said ball nut and said screw shaft, for facilitating a movement of said ball nut relative to said screw shaft, at least one guide member including a bar having a curved structure and engaged in said helical groove portion of said screw shaft, and including a cavity formed in said bar, and including a shank extended from said bar and engaged through said orifice of ball nut, and including an aperture formed in said shank and aligned with said passage of said ball nut for receiving the oil from said passage of said ball nut, and including a passageway formed therein and communicating with said aperture of said shank and said cavity of said bar for allowing the oil to flow from said passage of said ball nut into said cavity of said at least one guide member, and an oil retaining member engaged in said cavity of said at least one guide member and engaged with said helical groove portion of said screw shaft, for absorbing oil and for applying the oil onto said screw shaft.