Door opening and closing device

A door opening and closing device being applied to a vehicle including a vehicle body that includes a door opening;

• and a door that opens and closes the door opening, a part in the door corresponding to an upper end portion of the door opening when the door is at a fully closing position of fully closing the door opening is defined as a proximal end portion of the door, the door opening and closing device comprising:
• a slider that moves along a roof of the vehicle body in a direction intersecting with a width direction of the door, in a state of supporting the proximal end portion of the door in such a way as to be rotatable around an axis extending in the width direction;
• a main link mechanism that includes one end rotatably coupled to the vehicle body and an opposite end rotatably coupled to the door, and adjusts a posture of the door, depending on a door opening degree by changing a distance between coupling points that is a distance between a coupling point to the vehicle body and a coupling point to the door;
• and
• a sub-link mechanism that includes one end rotatably coupled to the vehicle body and an opposite end rotatably coupled to the door, and expands and contracts depending on the door opening degree, wherein
• the main link mechanism decreases the distance between the coupling points as the door opening degree becomes larger,
• the main link mechanism includes a first link that is rotatably coupled to the vehicle body, and a second link that is rotatably coupled to the door and rotatably coupled to the first link,
• the first link rotates around the coupling point to the vehicle body, thereby changing the distance between the coupling points of the main link mechanism,
• the sub-link mechanism causes the first link to rotate around the coupling point to the vehicle body, depending on an amount of rotation around the coupling point to the vehicle body,
• the main link mechanism includes a driven gear rotating around a rotational axis relative to the vehicle body, and
• the sub-link mechanism includes a drive gear meshing with the driven gear and rotating around a rotational axis relative to the vehicle body.