Abstract: In one embodiment, the present invention relates to a belt tensioning device for a hollow blind that comprises: a holder seat equipped with a lower belt gear on the top portion of the holder, the holder seat is in clearance fit with a lumen of a side frame of the hollow blind and is provided with a group of V-shaped slots from top to bottom therein, each V-shaped slot is equipped with a clip therein, the slip has a width slightly larger than the width of the lumen of the side frame of the hollow blind when being bent. The present invention allows the belt tensioning device to move along a single direction within the side frame of the hollow blind so that the distance between two belt gears can be gradually adjusted, thereby maintaining a proper tensioning force in the belt.

Abstract: The present invention relates to a built-in sun-shading device of hollow glass. The built-in sun-shading device comprises a cord-winding mechanism, a transmission mechanism controlling the rotation of the cord-winding mechanism and a sun-shading mechanism connected onto the cord-winding mechanism. The cord-winding mechanism comprises a cord-winding shaft, a group of cord-winding propellers are arranged on the cord-winding shaft, the transmission mechanism is connected with the cord-winding mechanism, and the sun-shading mechanism is connected onto the cord-winding propellers. The built-in sun-shading device of the hollow glass, which uses a single cord-winding shaft, can wind a plurality of cords and enable the sun-shading mechanism to be folded and unfolded in a balanced mode. The single cord-winding shaft does not need to move back and forth, is simple in terms of structure and has high assembling efficiency.

Abstract: The present invention relates to a built-in sun-shading device of hollow glass. The built-in sun-shading device comprises a cord-winding mechanism, a transmission mechanism controlling the rotation of the cord-winding mechanism and a sun-shading mechanism connected onto the cord-winding mechanism. The cord-winding mechanism comprises a cord-winding shaft, a group of cord-winding propellers are arranged on the cord-winding shaft, the transmission mechanism is connected with the cord-winding mechanism, and the sun-shading mechanism is connected onto the cord-winding propellers. The built-in sun-shading device of the hollow glass, which uses a single cord-winding shaft, can wind a plurality of cords and enable the sun-shading mechanism to be folded and unfolded in a balanced mode. The single cord-winding shaft does not need to move back and forth, is simple in terms of structure and has high assembling efficiency.