Winding device for a blind without pull cords

Abstract

A winding device for a blind without pull cords is provided with a reel pivotal base and a cord-guiding base abutting against each other in the upper rail of a blind. A winding reel is axially assembled on the reel pivotal base, having its outer circumference formed with an oblique conical surface gradually shrinking from its first end to its second end to enable a linking cord to move forward automatically when the linking cord is wound on the winding reel. The cord-guiding base is provided with at least one push block at a location where the winding reel is pivotally rotated for guiding the linking cord to be wound side by side closely on the winding reel, preventing the linking cord from overlapping or wound irregularly after the linking cord is wound on the winding reel, enabling a blind to be collapsed or stretched smoothly.

1 . A winding device for a blind without pull cords comprising: 
 A reel pivotal base installed at a preset portion of the upper rail of a blind;    A winding reel formed with a first end and a second end, said first end of said winding reel pivotally and axially assembled on said reel pivotal base, a linking cord having its first end fixed in said second end of said winding reel, said winding reel having its outer circumference formed with an oblique conical surface gradually shrinking from said first end to said second end; and    A cord-guiding base installed in said upper rail and abutting against said reel pivotal base, said cord-guiding base formed with a vertical wall, said vertical wall having its central upper edge cut with an arc-shaped notch, said arc-shaped notch receiving a relative portion of said winding reel, a gap formed between said winding reel and said arc-shaped notch.    
     
     
         2 . The winding device for a blind without pull cords as claimed in  claim 1 , wherein said reel pivotal base has its, bottom and one lateral wall respectively bored with a cord hole for a linking cord to pass therethrough.  
     
     
         3 . The winding device for a blind without pull cords as claimed in  claim 1 , wherein said vertical wall of said cord-guiding base is bored with a cord hole at one side near said arc-shaped notch for the second end of said linking cord to pass therethrough, said second end of said linking cord then threaded through said cord hole in the lateral wall and in the bottom of said reel pivotal base.  
     
     
         4 . The winding device for a blind without pull cords as claimed in  claim 1 , wherein said arc-shaped notch of said vertical wall of said cord-guiding base has a preset portion of its lateral edge provided with at least one protruding push block facing said second end of said winding reel, said push block guiding and pushing said linking cord to move toward said second end of said winding reel after said linking cord is threaded out of said cord hole of said vertical wall of said cord-guiding base, enabling said linking cord to be wound side by side orderly and closely on said winding reel.  
     
     
         5 . The winding device for a blind without pull cords as claimed in  claim 4 , wherein said push block of said cord-guiding base is formed with a support surface gradually slanting-up along the winding course of said linking cord.  
     
     
         6 . The winding device for a blind without pull cords as claimed in  claim 4 , wherein said arc-shaped notch of said cord-guiding base has its lateral edges orderly provided with a first push block and a second push block along the winding course of said linking cord.  
     
     
         7 . The winding device for a blind without pull cords as claimed in  claim 4 , wherein one side of said push block is flush with the inner edge of said arc-shaped notch.  
     
     
         8 . The winding device for a blind without pull cords as claimed in  claim 4 , wherein said vertical wall of said cord-guiding base has its opposite lateral walls respectively and symmetrically provided with a push block.  
     
     
         9 . The winding device for a blind without pull cords as claimed in  claim 6 , wherein said second push block of said cord-guiding base is formed with a support surface gradually slanting-up along the winding course of said linking cord, the lowermost portion of said support surface of said second push block about positioned at a same level of the support surface of said first push block.  
     
     
         10 . The winding device for a blind without pull cords as claimed in  claim 6 , wherein said second push block is arc-shaped and the length of said second push block is about one fourth of an imaginary circle of said arc-shaped notch of said cord-guiding base.  
     
     
         11 . The winding device for a blind without pull cords as claimed in  claim 1 , wherein a cover is covered on said winding reel and has one end engaged with said reel pivotal base, with a space formed between the inner wall of said cover and the outer wall of said winding reel for receiving said linking cord wound on said winding reel.