| 摘要 |
PROBLEM TO BE SOLVED: To provide a machine tool that can visually confirm whether or not airtightness of a window portion of the machine tool is appropriately kept.SOLUTION: The machine tool 1 comprises a cover body having a window portion 5. The window portion 5 comprises two transparent or translucent window plates 6 and 7 that are air-tightly jointed at a certain interval, where space 11 between the window plates 6 and 7 is set to pressure other than atmospheric pressure with a pressure adjusting device 12. An indicator provided with an indicating portion displaced depending on the pressure is connected to the cover body so that pressure in the space 11 acts on the indicating portion and the indicating portion can be visually confirmed from the outside. The position of the indicating portion is visually confirmed so that airtightness of the window portion 5 can be determined to be appropriate or not. |
