Fixing device for workpiece in machine tool and machine tool having the fixing device

A fixing device of a workpiece in a machine tool comprising:

• a fixing section configured to rotate with a main spindle, fix the workpiece in a closed state, and release the fixation of the workpiece in an open state;
• an actuating lever configured to rotate with the main spindle, and be displaced to open and close the fixing section;
• a sliding member which is provided to be movable between a first position and a second position along an axis direction of the main spindle, and configured to rotate with the actuating lever while displacing the actuating lever in contact with the actuating lever in the second position in the movable range;
• and
• a rotation transfer member which is disposed to have contact with the sliding member in the first position in the movable range of the sliding member, and configured to rotate with the main spindle, wherein
• the sliding member, the rotation transfer member and the actuating lever are disposed or formed such that the sliding member does not have contact with both of the rotation transfer member and the actuating lever at least in a partial range between the first position and the second position of the sliding member.