Patent ID: 7788987

Claim:
A self-lubricating ball screw comprising a screw shaft, a nut screwed on the screw shaft, and at least one oil tank detachably mounted on the screw shaft in a suspended manner and fixed to one end of the nut; characterized in that: the oil tank which is independent from the nut is provided with a protruding head fixed to the end of the nut and is provided with a horseshoe-shaped opening for allowing the oil tank to ride on the screw shaft in a suspended manner and to be removed from the screw shaft in a radial direction with respect to the screw shaft; the nut is defined with a receiving space in which is disposed a lubricating unit; the lubricating unit is formed with a protrusion and an absorbing portion, the protrusion of the lubricating unit maintains contact with the screw shaft, when the oil tank is installed on the nut, the absorbing portion will contact the oil tank to transmit oil from the oil tank to the lubricating unit.