Cutting machining apparatus

A cutting machining device comprising:

• a head to which a tool is fixed;
• a holding unit that is disposed to face the head, and configured to hold a workpiece;
• an interior case having a box shape, and in a surrounding wall, a first opening through which the holding unit is inserted and a second opening through which the head is inserted, at least a portion of the holding unit for holding the workpiece and the tool held by the head being disposed inside the interior case;
• a holding unit cover having a bottomed tubular shape, and, in a side wall, a holding unit insertion hole through which the portion of the holding unit for holding the workpiece is inserted, and being mounted on the holding unit while the portion of the holding unit for holding the workpiece is inserted through the holding unit insertion hole;
• a head cover having a bottomed tubular shape, and, in a bottom wall, a head insertion hole through which a portion of the head for holding the tool is inserted, and being mounted on the head while the portion of the head for holding the tool is inserted through the head insertion hole;
• a first cover that blocks between the holding unit cover and an outer circumferential portion of the first opening in the interior case;
• and
• a second cover that blocks between the head cover and an outer circumferential portion of the second opening in the interior case.