| 摘要 |
PURPOSE:To prevent thermal deformation of a lens by composing a lens unit in a laser torch of plural assembled lenses and circulating cooling medium between these lenses. CONSTITUTION:The lens unit 22 provided in the inner part of the laser torch 5 of a laser beam device is composed of an assembly of one upper and one lower lenses 16, 17 and a cooling space 21 which can circulate cooling medium 27 is formed between two lenses 16, 17. The lens unit 22 is cooled from the inside by circulating the cooling medium 27 in this cooling space 21. Therefore, the upper lens 16 and the lower lens 17 can be cooled efficiently. In this way, the cooling medium 27 can be prevented from giving an influence to machinability and the thermal deformation of the lens unit 22 is prevented. |
