| 摘要 |
PROBLEM TO BE SOLVED: To reduce lower manufacturing cost by using a less number of parts than in the case in which special members are provided including a return tube and a circulation piece. SOLUTION: The ball screw device uses individual two-streak screw grooves 31, 32 as closed loops for rolling and circulating a ball group 4 therein. Lower manufacturing cost is achieved by using a less number of parts than conventional. Even when the screw grooves 31, 32 are connected to each other via ball circulation grooves 33, 34 as regions burdened with no load, both ball circulation grooves 33, 34 are dislocated with each other in the direction of the screw grooves to reduce or eliminate regions burdened with no load in the peripheral direction of a nut member 2 and a screw shaft 3, thereby the degradation of load burdening capability of the ball screw device 1 is suppressed. COPYRIGHT: (C)2004,JPO&NCIPI |
