Coupling apparatus for car door

A coupling apparatus for a car door, the coupling apparatus comprising:

• a first member comprising a first hole;
• a second member comprising a second hole at a position corresponding to the first hole;
• and
• a coupler configured to mechanically couple the first member and the second member to each other,
• wherein a first latch projection is defined on an inner peripheral surface of the first hole of the first member,
• wherein the coupler comprises:
• a shaft extending in a vertical direction and having a shape for entering and rotatably passing through the first hole of the first member and the second hole of the second member;
• a stop portion disposed on a side of the shaft and configured to support the first member;
• a crossbar disposed on another side of the shaft and configured such that when the shaft is rotated to a final coupling position, the crossbar supports the second member and fixedly couples the second member to the first member;
• and
• a position maintaining portion comprising a groove portion and a separation prevention protrusion, the groove portion being disposed on an outer side of the shaft and configured to define a movement path along which the first latch projection moves, and the separation prevention protrusion being disposed on the groove portion and configured to prevent the first latch projection in the movement path from being separated from the shaft,
• wherein the first latch projection is disposed on the first member in an elastically movable manner such that when the first latch projection passes the separation prevention protrusion while coming into contact with the separation prevention protrusion, the first latch projection elastically moves in a direction away from the separation prevention protrusion, and
• wherein a buffer space is defined in the first member around the first hole by a through-hole penetrating the first member in the vertical direction, and
• wherein when the first latch projection passes the separation prevention protrusion, the first latch projection is moved toward the buffer space.