Shade lifting mechanism

Abstract

A window covering positioning system including a tube to facilitate raising and lowering of a window covering. The system further includes a rotational drive mechanism attached to the tube to drive rotation of the tube about an axis of the tube and an axial drive mechanism connected to the tube to drive movement of the tube in an axial direction. The axial drive mechanism is circumferentially disposed within the tube. A kit is further provided. The kit includes a tube around which a cord of a window covering is positioned and a rotational drive mechanism to rotate the tube about an axis of the tube. The kit further includes an axial drive mechanism to advance the tube in an axial direction and a connector to rotatably connect the tube to the axial drive mechanism.

1 . An apparatus comprising:
 a tube to facilitate raising and lowering of a window covering;   a rotational drive mechanism coupled to the tube to drive rotation of the tube about an axis of the tube; and   an axial drive mechanism coupled to the tube to drive movement of the tube in an axial direction, the axial drive mechanism circumferentially disposed within the tube.   
     
     
         2 . The apparatus of  claim 1  wherein a connector assembly rotatably couples the tube to the axial drive mechanism. 
     
     
         3 . The apparatus of  claim 1  wherein the axial drive mechanism is dimensioned to advance the tube in the axial direction a distance equal to a diameter of a lifting cord coupled to the tube with each complete rotation of the tube. 
     
     
         4 . The apparatus of  claim 1  wherein the rotational drive mechanism comprises a rotatable housing coupled to an inner surface of the tube. 
     
     
         5 . The apparatus of  claim 4  wherein an outer surface of the housing comprises a groove dimensioned to receive a key extending from an inner surface of the tube. 
     
     
         6 . The apparatus of  claim 1  further comprising:
 a stop ring coupled to the tube to limit rotation of the tube.   
     
     
         7 . The apparatus of  claim 1  further comprising:
 a sleeve coupled to an end of the tube proximal to the rotational drive mechanism.   
     
     
         8 . The apparatus of  claim 1  further comprising:
 a cord clip coupled to an outer surface of the tube.   
     
     
         9 . A method comprising:
 coupling a rotational drive mechanism to a tube for supporting a window covering; and   coupling an axial drive mechanism to an inner surface of the tube, the axial drive mechanism dimensioned to drive movement of the tube in an axial direction upon rotation of the tube by the rotational drive mechanism.   
     
     
         10 . The method of  claim 9  wherein the axial drive mechanism is coupled to the tube by rotatably positioning a cylindrical member around the axial drive mechanism and securing the cylindrical member to the tube. 
     
     
         11 . The method of  claim 10  wherein the axial drive mechanism and the cylindrical member comprise complimentary helical threading dimensioned to advance the tube in the axial direction a distance equal to a diameter of a window covering cord coupled to the tube with each complete rotation of the tube. 
     
     
         12 . The method of  claim 9  further comprising:
 coupling a stop ring to the tube to limit rotation of the tube.   
     
     
         13 . The method of  claim 9  further comprising:
 coupling a sleeve to an end of the tube proximal to the rotational drive mechanism.   
     
     
         14 . The method of  claim 9  further comprising:
 coupling a cord clip to an outer surface of the tube to secure a cord from the window covering to the tube.   
     
     
         15 . A kit comprising:
 a tube around which a cord of a window covering is positioned;   a rotational drive mechanism to rotate the tube about an axis of the tube;   an axial drive mechanism to advance the tube in an axial direction; and   a connector to rotatably connect the tube to the axial drive mechanism.   
     
     
         16 . The kit of  claim 15  further comprising:
 a bracket to support the tube.   
     
     
         17 . The kit of  claim 15  wherein the axial drive mechanism is dimensioned to advance the tube in the axial direction a distance equal to a diameter of the cord coupled to the tube with each complete rotation of the tube. 
     
     
         18 . The kit of  claim 15  further comprising:
 a stop ring to limit rotation of the tube.   
     
     
         19 . The kit of  claim 15  further comprising:
 a sleeve dimensioned to protect an end of the tube.   
     
     
         20 . The kit of  claim 15  further comprising:
 a cord clip to secure the cord to an outer surface of the tube.