Patent · US Expired

Method and apparatus for determining quality of welding at weld between working material pieces

US6399915B1 · kind B1 · utility

16Cited by
7References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 16, 2000
Grant dateJun 4, 2002
Priority date
Expiry dateMar 16, 2020

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K26/03
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

In a method for determining a quality of welding at a weld between working material pieces, an emission intensity of a visible light emitted from the weld during a laser welding using a laser device emitting a laser having a wavelength falling in a range of the wavelengths of near infra-red rays is detected, a first detection signal indicating the light emission intensity of the visible light is outputted, an intensity of a reflected light of the laser from the weld during the laser welding is detected, a second detection signal indicating the light intensity of the reflected light is outputted, frequencies of the first and second detection signals are analyzed and a determination is made whether a result of the laser welding falls in a favorable range of welding and an identification of a cause of welding failure of the weld if the determination that the result of the laser welding falls out of the favorable range is made on the basis of signal intensities of a first frequency component of each of the first and second detection signals lower than an arbitrary frequency in a range from 50 Hz to 200 Hz and of a second frequency component of each of the first and second detection sig…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.