| 摘要 |
The present invention relates to a dual roll blind enabling to control its light transmission amount and open and close with one ball-chain and to easily reset the roll screen. The dual roll blind comprises a first screen and a second screen having light transmission portions and light shielding portions, respectively, a first winding bar and a second winding bar for respectively winding the first screen and the second screen, a first gear for rotationally driving the first winding bar, a second gear for rotating the second winding bar with rotating dependently on the first gear, and a clutch hub, interposed between the second gear and the second winding bar, for transmitting rotational force of the second gear to the second winding bar, wherein the second gear comprises a gear protrusion protruding toward the clutch hub and the clutch hub comprises a clutch protrusion protruding toward the second gear to make contact with a portion of the gear protrusion for transmitting rotational force of the second gear to the clutch hub, and the gear protrusion and the clutch protrusion are not in contact with each other at a certain range of rotational angle in response to the rotational direction of the second gear to form a section where rotational force of the second gear is not transmitted to the clutch hub. |
