| 摘要 |
<p>To provide a ball screw mechanism of the type employing the spacers each between the neighboring balls, in which the phase relationship between the ball entry regions and the helical grooves can be easily controlled and which is substantially free from the problem in which the spacers would be seized or caught during a high speed rotation and which is robust, the ball screw mechanism includes a screw shaft 2 having a first helical groove 7 on an outer peripheral surface thereof, a nut member 3 mounted externally on the screw shaft and having a second helical groove 8 on an inner peripheral surface thereof and a series of balls 4 movably accommodated within the ball rolling passage 9 defined between the first and second helical grooves 7 and 8. A spacer 5 is interposed between the neighboring balls 4. A ball inverting passage 6 is defined in the nut member 3 and is cooperable with the ball rolling passage 9 to thereby define a generally closed ball recirculating passageway. The ball inverting passage 6 is defined in the nut member 4 by a return tube 14 or a guide plate 15. A deflector 11 having ball entry guide faces 11a defined by respective opposite ends thereof is firmly engaged in the second helical groove 8 of the nut member 3 with the ball entry guide faces 11a positioned adjacent the associated ball entry regions 6a of the ball inverting passage 6. <IMAGE></p> |
