Compact ball screw assembly
US5168767A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1991 |
| Grant date | Dec 8, 1992 |
| Priority date | — |
| Expiry date | May 29, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/18744
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A ball screw assembly includes a screw shaft hving a peripheral surface formed with a spiral groove, an outer sleeve fitted onto the screw shaft with a predetermined gap therebetween and a plurality of balls interposed between the screw shaft and the outer sleeve. A ball holder is provided in a radial hole formed in the outer sleeve and a ball is rotatably held in position and in engagement with the spiral groove by the ball holder. A fluid line is formed in the outer sleeve and the ball holder so that a pressuerized fluid may be supplied to establish a fluidic cushion between the ball holder and the ball. Also provided is a plurality of solid lubricants which are preferably arranged alternately with the balls and normally pressed against the spiral groove to keep the groove lubricated at all times.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.