Door opening and closing apparatus

A door opening and closing apparatus comprising:

• a body configured to define an opening and an interior space, wherein the opening is configured to be open toward an outside of a vehicle body, and the interior space is defined inside the vehicle body and communicates with the opening;
• a door configured to open and close the opening;
• a guide part disposed in the interior space and configured to guide the door such that the door moves in a first direction and a direction opposite to the first direction, wherein the first direction is a direction from the outside of the vehicle body to the inside of the vehicle body;
• and
• a transport part disposed in the interior space and configured to move the door in a second direction and a direction opposite to the second direction, wherein the second direction is a direction different from the first direction and away from the door,
• wherein, when the door transitions from a first state of closing the opening to a second state of opening the opening, the door is configured to perform a first maneuver to move in the first direction by being guided by the guide part and thereafter to perform a second maneuver to move in the second direction by the transport part,
• wherein, when the door transitions from the second state to the first state, the door is configured to perform a third maneuver to move in the direction opposite to the second direction by the transport part and thereafter to perform a fourth maneuver to move in the direction opposite to the first direction by being guided by the guide part,
• wherein the guide part includes a first guide groove and a second guide groove which extends from the first guide groove, and
• wherein the door includes a first protrusion protruding from the door toward the guide part and configured to be movably inserted into the first guide groove or the second guide groove.