A vehicle door opening and closing apparatus includes a rail configured to be mounted on a vehicle body, a roller unit configured to be mounted on a vehicle door, move along the rail, and allow the vehicle door to open and close in a sliding mode and a swing mode, a center rail configured to extend from a rear edge of a door aperture of the vehicle body, a center roller unit configured to be guided along the center rail, and a flap mechanism configured to prevent the center roller unit from being separated from the center rail in the sliding mode, and to allow the center roller unit to be released from the center rail in the swing mode.

A locking structure for a rectilinear center rail is provided. The locking structure includes a rectilinear center rail mounted on a sliding door, a center roller unit rollably connected to the center rail, and a center swing arm rotatably connected to the center roller unit and a vehicle body. The center roller unit includes a first lever and a second lever that are configured to rotate about rotation axes formed in a width direction of the center rail. The locking structure is configured to switch between a first posture in which the first lever is configured to be caught by a catching portion formed on the center rail, rotated, and then locked with the second lever and a second posture in which the second lever is configured to be caught by a catching portion formed on the center swing arm, rotated, and then locked with the first lever.

A spindle type structure includes a lower rail mounted in a longitudinal direction at a lower side of a vehicle body, a lower rail roller unit rollably connected to the lower rail, a lower rail swing arm rotatably connected to the lower rail roller unit and a door, a lower guide rail mounted on the door and configured to form a lower guide route in the longitudinal direction, and a spindle assembly positioned at one side of the lower rail, the spindle assembly including a spindle connected in the longitudinal direction to a fixing unit fixed to the vehicle body, having one end rollably connected to the lower guide rail, having a threaded portion formed on an outer circumferential surface thereof, and being configured to be movable in a threaded manner between the vehicle body and the door.

A structure for preventing opposite sliding doors from swaying is provided. The structure includes a lower rail mounted in a longitudinal direction at a lower side of a vehicle body, a lower rail roller unit rollably connected to the lower rail, a lower rail swing arm rotatably connected to the lower rail roller unit and a door, a guide roller unit fixedly connected to the lower rail, the guide roller unit including a guide roller rotatably connected to the lower rail, and a guide stopper fixedly connected to the door. The guide stopper includes a guide route formed inside the guide stopper and configured to serve as a rolling movement route for the guide roller, an exit/entrance portion formed at a first end of the guide route, and a stop portion formed at a second end of the guide route.

A dual lower rail structure for opposite sliding doors is provided. The dual lower rail structure includes a first lower rail mounted in a longitudinal direction at a lower side of a vehicle body, a second lower rail mounted in a longitudinal direction on a vehicle body at one side of the first lower rail, a first lower rail roller unit rollably connected to the first lower rail, a second lower rail roller unit having one end rollably connected to the second lower rail, and the other end connected to a sliding door, and a lower rail swing arm rotatably connected to the first lower rail roller unit and the sliding door.

A structure includes a lower rail mounted to a lower portion of a vehicle body in a longitudinal direction thereof. A lower-rail roller part is rollably connected to the lower rail. A lower-rail swing arm is rotatably connected to the lower-rail roller part and the door. A lower guide rail is mounted to the door and defines a lower guide path in the longitudinal direction of the vehicle body. A lifter has a first end that comes into contact with the lower guide path, and a second end that is fixed to the vehicle body, and applies a force in a direction of pushing the lower guide rail. An upper guide rail is mounted to an upper portion of the vehicle body. An upper-guide roller part is mounted to the door to be seated in the upper guide rail.

A structure can provide separation strength of an opposed sliding door. The structure includes a rail configured to be mounted to a vehicle body in a longitudinal direction thereof, a first bracket configured to be fixedly connected to the vehicle body at a first side of the rail and having a hook receiver, a slider inserted into the rail and coupled thereto, a swing arm configured rotatably connected to a sliding door and to the slider, and a second bracket fixedly connected to the swing arm. The second bracket has on a first side thereof a hook to be received in the hook receiver. The hook is received in the hook receiver when a load is applied to the sliding door in a direction from an inside to an outside of the vehicle body with the sliding door being closed.

A vehicle slide door support device connects a slide door to a vehicle body. The slide door is configured to open and close a door opening formed in a side surface of the vehicle body. The device includes: a first guide rail arranged on a lower portion of the slide door and regulating a movement direction of the slide door; a first hinge unit arranged below the door opening and configured to move relative to the first guide rail in a longitudinal direction of the first guide rail; a second guide rail arranged above the first hinge unit on the vehicle body and regulating the movement direction of the slide door; and a second hinge unit arranged above the first guide rail on the slide door and configured to move relative to the second guide rail in a longitudinal direction of the second guide rail.

A structure can help to prevent deviation of a sliding door. The structure includes a lower rail mounted in a longitudinal direction of a vehicle body, a slider inserted into and rollably coupled to the lower rail, a swing arm rotatably coupled to the slider and a door of a vehicle, and a lifter having a first end rotatably coupled to the swing arm and a second end rotatably coupled to the door. The lifter is configured to move along with a rectilinear motion or a rotational motion of the swing arm. One end of the swing arm coupled to the door and the other end of the lifter coupled to the door are spaced apart from each other at a predetermined distance and support the door.

A retention and guide assembly for a vehicle door includes a guide track connected to a door panel of the vehicle door. The guide track includes sidewalls that at least partially extend around and define an internal recessed volume. The sidewalls include a first sidewall coupled with the door panel and a second sidewall coupled with and oriented transverse to the first sidewall. The guide track includes a retaining flange that is coupled with and oriented transverse to the second sidewall. The sidewalls and the retaining flange are shaped to receive (within the internal recessed volume) a roller of a control arm extending from a vehicle body. The retaining flange engages the control arm and/or the roller and retain the roller within the internal recessed volume of the guide track between the second sidewall and the door panel of the vehicle door.