Laser drilling breakthrough detector
US6140604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1998 |
| Grant date | Oct 31, 2000 |
| Priority date | — |
| Expiry date | Jun 18, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K26/382
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
In a pulse laser drilling process having a machine control for controlling a laser, an apparatus is provided to detect when a hole is drilled through a workpiece. The apparatus detects a laser pulse, where the laser pulse emits a laser light upon drilling impact with the workpiece. A second detection step detects sparks emitted by the workpiece, and a spark signal amplitude representative thereof is produced. The sparks produce visible wavelength light. A filter blocks the laser light and transmits the visible wavelength light. A photosensor associated with the filter senses when the spark signal amplitude diminishes below a predetermined threshold level. An output signal, responsive to the photosensor indicates when a through hole is complete and indicates to the machine control to stop any further laser pulse.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.