Sliding door device for vehicle

A sliding door apparatus for a vehicle, the sliding door apparatus comprising:

• a door panel configured to open or close a door opening formed in a vehicle body;
• a center rail mounted on a center portion of the door panel to extend in a longitudinal direction of the vehicle body;
• a center roller;
• an upper trim provided at an upper side of the vehicle body and a lower trim provided at a lower side of the vehicle body;
• and
• a center roller mounting bracket,
• wherein the center rail provides a path for the center roller mounted on a center portion of the vehicle body to move therealong,
• wherein the door panel is covered by the upper trim at the upper side of the vehicle body and the lower trim at the lower side of the vehicle body,
• wherein a lower portion of the upper trim and an upper portion of the lower trim are disposed to overlap each other vertically,
• wherein the center roller is mounted on the center roller mounting bracket including a first surface extending toward the vehicle body to be vertical to the door panel, a second surface bent from the first surface toward a lower side of the vehicle body, and a third surface extending from the second surface toward the vehicle body to be vertical to the door panel,
• wherein the center roller mounting bracket is disposed to be interposed and extend between the lower portion of the upper trim and the upper portion of the lower trim, and
• wherein the sliding door apparatus further includes a rod bearing configured to be located outside a lower end portion of the center rail, contact with and support the lower end portion of the center rail upwards to rotate according to movement of the center rail and mounted on the second surface of the center roller mounting bracket, thereby preventing the door panel from sagging downward and stably supporting the door panel.