Ball screw
US6993992B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2003 |
| Grant date | Feb 7, 2006 |
| Priority date | — |
| Expiry date | Jun 30, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/19777
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A ball screw which is little subject to deterioration of operating characteristics and occurrence of wear, torque change, noise, vibration, etc. during operation due to stagnation or competition of balls. The ball screw includes a screw shaft having a helical thread groove formed on the outer surface thereof and a nut having a thread groove formed on the inner surface thereof corresponding to the thread groove on the screw shaft which engages with the screw shaft with the interposition of a number of balls rollably provided in a helical ball rolling path formed between the two thread grooves, and spacers between adjacent ones of the number of balls, wherein the variation of the total of the gap between the balls and spacers during the rolling of the balls is smaller than 1/20 of the diameter of the ball.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.