Laser cutting apparatus with a high quality laser beam
US7348517B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 2005 |
| Grant date | Mar 25, 2008 |
| Priority date | — |
| Expiry date | Sep 1, 2025 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K26/14
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A laser cutting apparatus capable of properly cutting a workpiece having a large thickness with a laser beam. The laser cutting apparatus includes a gas laser oscillator; and an optical system including a collective lens and transmitting and collecting a laser beam generated in the gas laser oscillator to irradiate a workpiece with the laser beam. An index M2 for evaluating a beam quality of the laser beam emerging from the optical system, with which the workpiece is irradiated, is in a range of 2.8 to 4.5; while the index M2 is defined by a formula: M2=π×(dm)2/(4×λ×Zr); in which λ is a wavelength of the laser beam; dm is a minimum beam diameter of the laser beam in a predetermined optical-path range including a focal point of the collective lens; and Zr is a distance between a first position on an optical axis, at which the minimum beam diameter dm is established, and a second position on the optical axis, at which a beam diameter “21/2×dm” is established, in the laser beam in the predetermined optical-path range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.