Patent ID: 7621586

Claim:
A sliding door system for a vehicle wherein a sliding door slides from a door opening toward a rear end of the vehicle, the system comprising: a roller bracket having a hinged connection at one end for coupling to the sliding door and having orthogonal rollers at the other end; a fixed primary track for mounting to a side of the vehicle and extending away from the door opening to a terminus, the primary track having a generally C-shaped cross section with a first vertical load portion and a first horizontal load portion, the first load portions receiving the orthogonal rollers; a concentric track bracket for mounting to the side of the vehicle and having at least a portion disposed between the terminus of the primary track and the rear end of the vehicle, the concentric track bracket having a generally C-shaped cross section greater than and substantially coaxial with the primary track; and a track extension having a first end and an interlock end, the track extension slidably received in the concentric track bracket between a retracted position and an extended position, wherein the track extension is locked in coaxial abutment with the terminus of the primary track when in the retracted position and wherein the interlock end extends past the rear end of the vehicle when in the extended position, the track extension having a generally C-shaped cross section with a second vertical load portion and a second horizontal load portion, the second load portions aligned with the first load portions, respectively, for receiving the orthogonal rollers when the roller bracket moves from the primary track to the track extension; wherein when the roller bracket moves in an opening direction from the primary track into the track extension and then to the interlock end, the track extension remains in the retracted position; wherein when the orthogonal rollers enter the interlock end then they are captured and the track extension is released to slide within the concentric track to the extended position; and wherein when the track extension returns from the extended position to the retracted position then the orthogonal rollers are released from the interlock end, thereby enabling the roller bracket to slide through the track extension and back into the primary track.