Patent ID: 8082814

Claim:
A ball screw device comprising: a screw shaft including an outer thread formed thereon, a ball nut including a bore formed therein for receiving said screw shaft and for forming a first gap between said ball nut and said screw shaft and for receiving a lubricating oil, and including an inner thread formed in said ball nut and aligned with said outer thread of said screw shaft for forming a helical raceway between said ball nut and said screw shaft, a plurality of bearing members engaged in said helical raceway that is formed between said ball nut and said screw shaft for facilitating a movement between said ball nut and said screw shaft, a barrel attached to said ball nut and moved in concert with said ball nut for forming a second gap between said barrel and said screw shaft and for communicating with said first gap formed between said ball nut and said screw shaft, said barrel including at least one aperture formed therein and communicating with said second gap formed between said barrel and said screw shaft for allowing the lubricating oil to flow into said second gap formed between said barrel and said screw shaft and said first gap formed between said ball nut and said screw shaft, said barrel including an outer peripheral portion having a helical channel formed therein for receiving the lubricating oil, said at least one aperture being communicating with said helical channel of said barrel, a receptacle rotatably engaged onto said barrel for closing said helical channel of said barrel and for retaining the lubricating oil within said helical channel of said barrel, a bearing housing rotatably engaged onto said ball nut and attached to said receptacle, and a plurality of rolling elements engaged between said ball nut and said bearing housing for facilitating a rotating movement between said ball nut and said bearing housing.