Patent ID: 8281846

Claim:
A curtain comprising a curtain bracket, a rotation driving device mounted on an end of the curtain bracket, a curtain reeling drum or a reeling rope device driven by the rotation driving device, a curtain cloth driven by the curtain reeling drum or a curtain cloth or shade driven by a reeling rope of the reeling rope device, and a reverse rotation releasing device connected to the rotation driving device, wherein the rotation driving device comprises a pull rope rotary disc box fixed to the curtain bracket, a pull rope rotary disc rotatably mounted in the pull rope rotary disc box and wound with a pull rope for drawing downwardly to drive the pull rope rotary disc to rotate, and a unidirectional clutch device connected to the pull rope rotary disc, wherein a rewinding spring is provided between the pull rope rotary disc and the pull rope rotary disc box or the curtain bracket for reversely rotating the pull rope rotary disc to reel the pull rope back to the pull rope rotary disc when releasing the pull rope, wherein the unidirectional clutch device comprises an axial hole connected to the pull rope rotary disc box, a rotary shaft mounted in the axial hole for driving the curtain reeling drum or the reeling rope device, and a clutch sliding rotary head located on one end of the rotary shaft, wherein teeth for unidirectional engagement are formed on end surfaces where the rotary shaft and the clutch sliding rotary head are connected, wherein a jacket is mounted on a side of the pull rope rotary disc, wherein another end of the clutch sliding rotary head is located in the jacket at the side of the pull rope rotary disc, wherein an inclined slot is formed in an exterior surface of the other end of the clutch sliding rotary head, wherein a slider is mounted in the jacket at the side of the pull rope rotary disc and corresponding to the inclined slot, wherein a spring coil is connected between the exterior surface of the clutch sliding rotary head and the axial hole, and wherein the jacket and the slider are rotated together with the pull rope rotary disc when the pull rope rotary disc is rotated.