Optical Processing head, optical processing apparatus, and control method and control program of optical processing apparatus

Patent metadata

Field	Value
Publication number	US-9959613-B2
Application number	US-201514889361-A
Country	US
Kind code	B2
Filing date	Mar 20, 2015
Priority date	Mar 20, 2015
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

This specification discloses an optical processing head including a light guide portion that guides, to a process surface, a ray for processing. The light guide portion is further configured to guide, to the process surface, a ray for inspection different in wavelength from the ray for processing. The optical processing head further includes an inspection portion that inspects the state of the process surface based on reflected light of the ray for inspection reflected by the process surface. With the optical processing head, the state of the process surface can be easily inspected even during optical processing.

First claim

The invention claimed is:

1. An optical processing head comprising:
a light guide that guides, to a process surface, a ray for processing and a ray for inspection different in wavelength from the ray for processing; and
an inspection unit that inspects a state of the process surface from reflected light of the ray for inspection reflected by the process surface,
wherein letting c be a light velocity, h be a Planck constant, and κ be a Boltzmann constant with respect to a maximum temperature T assumed on the process surface, a relation between a wavelength λ and luminance I of the ray for inspection is given by:
I (λ)>(2 hc 2 /λ 5 )/[exp hc/ λκT −1].

2. The optical processing head according to claim 1 , wherein the state of the process surface is a tilt of the process surface or a concentration of a processing material on the process surface.

3. The optical processing head according to claim 1 , wherein the wavelength of the ray for inspection is not larger than 1 μm.

4. The optical processing head according to claim 3 , wherein the ray for inspection is ultraviolet light or blue light having a wavelength of not larger than 500 nm.

5. The optical processing head according to claim 1 , wherein said inspection unit includes an image capturing unit that captures a spot image of the ray for inspection.

6. An optical processing head, comprising:
a light guide that guides, to a process surface, a ray for processing and a ray for inspection different in wavelength from the ray for processing; and
an inspection unit that inspects a state of the process surface from reflected light of the ray for inspection reflected by the process surface, wherein said inspection unit includes a comparator that compares the spot image of the ray for inspection with a reference spot image.

7. The optical processing head according to claim 6 , wherein the reference spot image is an image obtained by capturing an image of the ray for inspection reflected by a reference process surface perpendicular to an optical axis of the ray for processing.

8. The optical processing head according to claim 7 , wherein the comparator calculates a tilt angle of the process surface with respect to the reference process surface, based on a distance between a spot center included in the spot image of the ray for inspection and a reference spot center included in the reference spot image.

9. The optical processing head according to claim 7 , further comprising a nozzle that ejects a processing material toward a molten pool formed on the process surface by the ray for processing,
wherein the reference spot image is an image obtained by capturing an image of the ray for inspection reflected by the process surface to which the processing material is not ejected.

10. The optical processing head according to claim 9 , wherein the comparator calculates, from a difference in size between the spot image of the ray for inspection and the reference spot image, a concentration of the processing material in gas on the process surface.

11. The optical processing head according to claim 10 , further comprising an adjuster that adjusts an ejection amount of the processing material based on the concentration of the processing material.

12. The optical processing head according to claim 5 , wherein
the image capturing unit is arranged off the ray for processing, and
said inspection unit further includes a first one-way mirror that transmits the ray for processing, and guides the ray for inspection reflected by the process surface to the image capturing unit.

13. The optical processing head according to claim 12 , wherein
an emitter of the ray for inspection is arranged off the ray for processing, and
said inspection unit further includes a second one-way mirror that transmits the ray for processing, and guides the ray for inspection emitted by the emitter to the process surface.

14. The optical processing head according to claim 13 , wherein a reflecting surface of the first one-way mirror and a reflecting surface of the second one-way mirror are symmetrical about a plane perpendicular to an optical axis of the ray for processing.

15. An optical processing apparatus comprising:
an optical processing head defined in 1 ;
a light source for processing that emits the ray for processing; and
a light source for inspection that emits the ray for inspection.

16. An optical processing apparatus comprising:
an optical processing head defined in claim 8 ; and
a controller that controls a tilt of one of the process surface and the optical processing head in accordance with the calculated tilt angle.

17. An optical processing apparatus comprising:
an optical processing head defined in claim 10 ; and
a controller that controls an ejection amount of the processing material in accordance with a concentration of the processing material.

18. A control method of an optical processing apparatus defined in claim 16 , comprising controlling a tilt of one of the process surface and the optical processing head in accordance with the calculated tilt angle so as to locate the process surface and the optical processing head at predetermined relative positions.

19. A control method of an optical processing apparatus defined in claim 17 , comprising controlling an ejection amount of the processing material to make a concentration of the processing material fall within a predetermined range.

20. A control program of an optical processing apparatus defined in claim 16 , causing a computer to execute controlling a tilt of one of the process surface and the optical processing head in accordance with the calculated tilt angle so as to locate the process surface and the optical processing head at predetermined relative positions.

21. A control program of an optical processing apparatus defined in claim 17 , causing a computer to execute controlling an ejection amount of the processing material to make a concentration of the processing material fall within a predetermined range.

Assignees

• Tech Res Association Future Additive Manufacturing

Inventors

• Ohno Hiroshi
• Obara Takashi
• Sasaki Yuji
• Sasaki Mitsuo
• Masukawa Kazuyuki

Classifications

• B23K26/1464

  Supply to, or discharge from, nozzles of media, e.g. gas, powder, wire · CPC title

• B23K26/144

  the fluid stream containing particles, e.g. powder · CPC title

• G02B27/144

  using partially transparent surfaces without spectral selectivity (G02B27/147 takes precedence) · CPC title

• B23K26/342

  Build-up welding · CPC title

• B29C67/00

  Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00 · CPC title