| 摘要 |
PROBLEM TO BE SOLVED: To provide a ball screw device capable of preventing ball aligning members incorporated in an endless circulation path of a nut member from being in contact with a screw shaft, preventing such ball aligning members from being caught by anything during circulation in the endless circulation path, allowing the balls to smoothly circulate and the nut member to smoothly move in relation to the screw shaft, and preventing such ball aligning members from wearing away to the utmost. SOLUTION: Guide pieces, each of which projects from the diameter of a ball 1 on both sides in the direction in which the balls 1 are aligned, are formed on ball aligning members 2 for aligning the balls at specified intervals in an endless circulation path of a nut member 20, whereas the guide pieces of the ball aligning members 2 are accommodated in the inside diameter of an endless circulation path forming member 50 which is loaded to the nut member 20 to form the endless circulation path. A pair of guide grooves 53 are formed along the direction in which the ball 1 rolls. On both sides of load-rolling grooves 35 of the nut member 20 the guide pieces A of the ball aligning members 2 are accommodated, and a pair of guidance grooves continuously connected to the guide groove 53 are formed. |
