Patent ID: 8118378

Claim:
A rail assembly, comprising: an outer rail, a middle rail, an inner rail, and a retrieving unit, wherein the outer rail has an outer rail space for accommodating the middle rail, the inner rail and the retrieving unit; the middle rail slides in the outer rail space, and has a middle rail space for accommodating the inner rail; the inner rail accommodated in the middle rail, and sliding in the middle rail space; and the retrieving unit assembled on one end of the outer rail space, and comprises: a fixing part, disposed in the outer rail space, such that one end of the outer rail space is made into a closed end, the other end is made into an opened end; a sliding rail, disposed on the outer rail at the opened end; a moving part, disposed in the outer rail space, and sliding along the sliding rail; a buckling mechanism, disposed on the moving part; at least one elastic part, disposed between the fixing part and the moving part; and a guiding part, disposed on the inner rail and corresponding to the buckling mechanism; wherein the moving part slides along the sliding rail in the outer rail space at the opened end, the movement of the moving part are not restricted by a length of the fixing part; wherein in the outer rail space, the moving part has two receiving slots on the both sides and the fixing part also has the two receiving slots on the both sides or between the fixing part and the outer rail; wherein when the moving part slides in the outer rail space, the inner rail extends through the receiving slots and closes to the closed end of the outer rail, so as to increase a sliding scope and a length of the inner rail; the rail assembly has a maximum length and strength.