| 摘要 |
A feeding apparatus which employs a ball screw includes a movable table movably supported on a fixed bed. A ball screw shaft is supported at one of its ends by the fixed bed in such a manner that the ball screw shaft is movable in the direction of rotation thereof and immovable in the axial direction thereof. A ball nut is fitted on the ball screw shaft through steel balls and is supported by the movable table in such a manner that the ball nut is movable in the direction of rotation thereof and immovable in the axial direction thereof. A first drive source is mounted on the fixed bed to rotate the ball screw shaft, and a second drive source is mounted on the movable table and operatively connected to the ball nut through a hollow transmission shaft. The ball screw shaft has the other end thereof concentrically received in the hollow inside of the transmission shaft in such a manner that the ball screw shaft is rotatable and movable relative to the transmission shaft in the axial direction thereof. |
