Fatigue life enhancement of dovetail connector slots and noncircular openings
US4885829A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 16, 1989 |
| Grant date | Dec 12, 1989 |
| Priority date | — |
| Expiry date | Feb 16, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T408/03
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A pair of openings (14) are drilled in a workpiece (12) at locations spaced inwardly from an edge (76) of the workpiece (12). Each opening is cold-expanded by the passage of a mandrel (46') only, or a mandrel (46) and split sleeve (58), to create an annular zone of residual compressive stresses (72) in the workpiece material immediately surrounding the openings (14'). Then the workpiece (12) is cut along lines extending from the edge (76) inwardly to central regions of the cold-expanded openings (14'). The workpiece material between the two openings (14') and the two cuts (74) is removed. The edge portions (72) of the material in the vicinity of the cuts (74) and the openings (14') are machined to a final desired size and shape, to define connector slots (84) having cold-expanded round regions bounding the slots (84).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.