| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve workability and refrigerant sealing characteristic when a plurality of nuts are connected together in a ball screw in which a plurality of nuts are connected on one screw shaft and assembled there, a refrigerant is flowed in through-holes axially arranged at the plurality of nuts to cool the nuts.SOLUTION: This ball screw 1 has counter bores 4, 5 formed at each of the opposite side end surfaces of through-holes 3 of the adjoining nuts 21, 22 and annular seal members 6 inserted into the counter bores. The counter bores 4, 5 are formed such that a depth D2 of one counter bore is deeper than a length of the seal member 6 (D2>L) and the other depth D1 is shallower than the length of the seal member 6 (D1<L) and at the same time peripheral positions of the counter bores 4, 5 of the adjoining nuts 21, 22 are formed to be oppositely faced at positions where a desired pre-pressure is applied.</p> |
