Real-time magnetic-flux breakthrough detection method and system for laser drilling
US5013886A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 1990 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Jul 23, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K26/0342
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Detection of the breakthrough of a laser beam through a workpiece wall uses one or more magnetic field pick-up coils. The coils are disposed on the drill side (side upon which the laser beam is impinging) of the workpiece. The coils sense the magnetic fields generated in the ionized plasma of particles escaping from the impact of the laser on the surface. The coils are connected to a breakthrough detector which generates a breakthrough signal upon the plasma and associated magnetic fields disappearing at breakthrough. The breakthrough signal is used to turn off the laser and/or change the application point at which the laser beam strikes the workpiece.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.