Patent ID: 7370683

Claim:
A lifting-cord winding mechanism of a solar-radiation shielding device having a head rail, a case removably fixed in said head rail, a drive shaft rotatably supported in said head rail, a winding drum fitted around said drive shaft so that said winding drum is rotatable integrally with said drive shaft, a slit disposed at the bottom part of said case, a ring fitted around said winding drum so that said ring is rotatable integrally with said winding drum but is slidable axially along said winding drum, two sidewalls bearing said winding drum at both ends of said case, and a lifting cord inserted into said case through said slit with the tip thereof attached to said ring, said lifting-cord winding mechanism of a solar-radiation shielding device wherein: a guide is disposed either in said case or said head rail, said lifting-cord entering into said case via said guide, and said winding drum is formed in a circular-cone shape at one end portion thereof with the larger-diameter end of said circular-cone shape disposed at said one end, and is formed in either another circular-cone shape or a cylindrical shape at a portion thereof continuing to said one end portion thereof, said another circular-cone shape having a conical angle that is the same as or smaller than the conical angle of said circular-cone shape formed at said one end portion thereof, and said sidewall surrounding said one end portion of said winding drum has an inclined surface formed on the internal surface thereof, said inclined surface diagonally extending toward outside, and said lifting cord has said tip thereof attached to a knob, said knob removably fixed to said ring.