Method and apparatus to coldwork holes
US5943898A · kind A · utility
Inventor
Key dates
| Filing date | Feb 17, 1998 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Feb 17, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23P9/025
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for coldworking holes using a pre-lubricated tubular seamless sleeve made of shape memory alloys. The apparatus uses a pre-lubricated tubular seamless sleeve made of shape memory alloys, a mandrel having a larger diameter end, a nose cap with rough conical surface, and a spacer with rough complementary conical surface. The sleeve is placed and sufficiently firmly held between the conical surfaces of the nose cap and spacer which are carried in a mandrel pulling means. The larger diameter end of the mandrel passes forwardly through and out of the sleeve whose diameter is therefore elastically expanded by the passing mandrel and thereafter restores to its original diameter because of the superelastic property of the shape memory alloys. The smaller diameter portion of the mandrel is surrounded and within the sleeve. The sleeve together with the mandrel are then inserted into a hole in an associated workpiece. The nose cap being carried on the mandrel pulling means is placed against the workpiece. The mandrel retracts backwardly through and out of the sleeve; thereby expands the sleeve wall against the hole wall and exerts radially outward forces on the sleeve, …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.