CUTTING DEVICE

Provided is a cutting device that can easily attach and detach a cutting blade. Cutting means having a cutting blade， a rotating shaft rotatably supported on the spindle housing， a mount fitted to the front end of the rotating shaft to support the cutting blade， and a fixing flange fixing the cutting blade supported on the mount to the mounter The mount is provided with a boss portion which is slidably supported in the axial direction by fitting into a fitting hole formed in the central portion of the fixing flange， and a collar having a support surface on the front surface protruding in the radial direction from the outer periphery of the boss portion. A portion， a cylindrical portion provided on the rear side of the collar portion， the collar portion is provided with a suction hole opening on the support surface side， the cylindrical portion is provided with a communication path communicating with the suction hole， the communication path provided in the cylindrical portion It is connected to the suction means through a rotary joint， and the suction means is operated to The cutting blade by aspiration to the fixing flange on the side mountable through the passage and the suction holes by applying a negative pressure between the mounter and the fixing flange is fixed between the mounter and the fixed flange.