Machine tool system and stocker

A machine tool system comprising:

• a machine tool including a processing chamber and a door, the processing chamber being covered by a cover having a door opening, the door for covering or uncovering the door opening;
• a stocker for being removably mounted on the machine tool, positioned outside the processing chamber, encircled in three peripheral directions each by a protective member which is a fence or a wall, and having a stocker opening in a remaining one peripheral direction;
• and
• a robot,
• wherein
• when the stocker is mounted on the machine tool, a storage space encircled by the protective member is in communication with the processing chamber through the stocker opening and the door opening, and ends of the protective member positioned at both sides of the stocker opening are positioned in proximity of or come in contact with the cover to an extent to prevent entrance of a human, and when the stocker is mounted on the machine tool, the robot moves in a movement range that spans the storage space and the processing chamber.