Door support device

A door support device that causes a vehicle body having a door opening to support a door that opens and closes the door opening, the door support device comprising:

• a main link with a proximal portion rotatably connected to the vehicle body and a distal portion rotatably connected to the door;
• a sub-link with a proximal portion rotatably connected to the vehicle body and a distal portion rotatably connected to the door, each of the portions being connected at a position different from a position for the main link;
• and
• a door drive unit that applies a load to the door in at least an opening direction of the opening direction and a closing direction of the door, wherein
• the main link and the sub-link constitute a four-bar link mechanism together with the vehicle body and the door, and
• the main link includes an adjusting mechanism for adjusting a distance between a connecting portion connected to the vehicle body and a connecting portion connected to the door.