Patent ID: 9249620
Filing Date: 2016-02-02
CPC Classification: E06B

Claim Text:
1. A roll blind comprising: a supporting frame disposable in a window frame and having a pair of end plates disposed at first and second ends of the supporting frame; first and second winding bars rotatably disposed in the end plates of the supporting frame; a winding driver rotationally driving one of the first and second winding bars; first and second screens coupled to the first and second winding bars, respectively; a weight bar to which the lower ends of the first and second screens are fixed; and a clutch unit binding and unbinding the first and second winding bars with respect to each other, wherein the clutch unit includes a driving gear fixedly coupled to the winding driver and a driven gear disposed to be bound to and unbound from the second winding bar, wherein an intermediate gear is interposed between the driving gear and the driven gear, and wherein the driven gear has an arc-like clutch groove formed in one surface thereof, the clutch groove has first and second end portions, the second winding bar has a clutch protrusion, the driven gear is selectively bound to or unbound from the second winding bar by guiding the clutch protrusion in the clutch groove and bringing the clutch protrusion into selective contact with the first and second end portions of the clutch groove, and wherein during rotation of said one of the first and second winding bars in opposite directions by the winding driver, the first and second winding bars are simultaneously rotated in a first direction when the clutch protrusion is in contact with the first end portion of the clutch groove and in an opposite direction when the clutch protrusion is in contact with the second end portion of the clutch groove.