Abstract: A vehicle door device includes first and second link arms each having a first pivot connection point with respect to a vehicle body and a second pivot connection point with respect to a door of a vehicle; a door side fitting portion provided at a closing side end portion of the door that opens and closes a door opening portion of the vehicle based on an operation of a link mechanism formed by the first and second link arms; and a vehicle body side fitting portion provided at a closing side end portion of the door opening portion with and from which the closing side end portion of the door comes in contact and separates based on an opening or closing operation of the door.

Abstract: A door opening and closing device includes a slider and a main link mechanism. The slider moves along a roof of the vehicle body in a front-rear direction, while supporting a proximal end portion of a back door in such a way as to be rotatable around an axis extending in a width direction. The main link mechanism includes one end and an opposite end rotatably coupled to the vehicle body and the back door, respectively. The main link mechanism adjusts a posture of the back door, depending on a door opening degree by changing a distance between a coupling point to the vehicle body and a coupling point to the back door. The main link mechanism decreases the distance as the door opening degree becomes larger.

Abstract: A guide rail includes: a first rail that has a bottom wall on which a load roller rolls and supports the weight of a sliding door; a second rail that has side walls on which two guide rollers roll and defines a moving direction of the sliding door; and a first restriction part that restricts the motion of the load roller in an axial direction.

Abstract: A cover device includes a cover that is displaced between a covering position where an upper side of a striker is covered, and an exposure position where the striker is exposed upward, and an open-close mechanism that displaces the cover to the covering position when a slide door performs an opening operation, and displaces the cover to the exposure position when the slide door performs a closing operation.

Abstract: A slide door support device supports a slide door that opens and closes a door opening formed on a side surface of a vehicle body. The slide door support device includes first and second lower rails and a lower guide unit. The lower guide unit includes a first lower guide roller moving along the first lower rail, a second lower guide roller moving along the second lower rail, a lower fixed portion fixed to the slide door, a lower rotational arm rotatable relative to the lower fixed portion and supporting the first and second lower guide rollers, and a pressing member pressing the lower fixed portion. An arm angle made by the lower fixed portion and the lower rotational arm gradually decreases as an opened degree of the slide door decreases. The pressing member presses the lower fixed portion in a direction of increasing the arm angle.

Abstract: A slide door support device supports a slide door that opens and closes a door opening formed on a side surface of a vehicle body. The slide door support device includes first and second lower rails, an upper rail, and lower and upper guide units. The upper rail includes a straight portion extending to a vehicle front, and a curved portion curved so as to extend inward in a vehicle width direction as a position shifts from a front end of the straight portion to the vehicle front. The upper guide unit includes first and second upper guide rollers that move along the upper rail, an upper load roller rolling on a rolling surface that extends along the upper rail, and an upper rotational arm connected so as to be rotatable relative to the slide door and supporting the first and second upper guide rollers and the upper load roller.