To smooth rotation of a pulley so as to open/close a curtain smoothly by providing with a metal pipe which is the rotational center of a rotary pulley, and the fixing means of the pipe.
Wires are penetrated on rotary pulleys 2c, 2d, and the respective wires are moved in an opposite direction by rotation of a drum. At this time, the rotary pulleys 2c, 2d whose rotational center is metal pipe 12 are fit to each other by the metal pipe 12, the rotational direction of the pipe 12 is fixed by a bolt 13, and thereby, the rotary pulleys 2c, 2d are rotated smoothly without generating looseness. A shaft 14 is penetrated on the pipe 12 of a center pulley. It is thus possible to eliminate twist of the center pulley so as to smoothly rotate the rotary pulleys 2c, 2d furthermore.
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