LAP JOINT TYPE ADJUSTABLE RAIL

Disclosed is a lap joint type adjustable rail. The lap jointing rail (1-2) is nested on the outside of a fixed rail (1-1), a motorized curtain rail is lap jointed by means of the lap jointing rail (1-2) and the fixed rail (1-1), forming a nested-type rail structure with an adjustable length. The lap jointing rail (1-2) is a profile of irregular shape, and viewed from the port direction thereof, the inner shape of the lap jointing rail (1-2) is identical to the outer shape of the fixed rail (1-1), so as to enable the lap jointing rail (1-2) to fully nest and slide on the outside of the fixed rail (1-1). The outside of the lap jointing rail (1-2) is provided with a working face used for a locking screw (1-4), and the position of the working face is located on a extension line of the connection site between the lap jointing rail (1-2) and the fixed rail (1-1). The lap joint type adjustable rail has a simple structure, is convenient to install, can meet the size adjustments of motorized curtains with different in