Equilibrium device for a blind without pull cords

Abstract

An equilibrium device for a blind without pull cords includes at least one movable weight-balancing member installed at a proper location in the interior of the lower rod of a blind. The weight-balancing member is provided for increasing and adjusting the weight of the blind so as to keep the weight of the blind and the elastic force produced by an elastic force mechanism in a force balanced condition after the blind is cut in width and lightened, enabling the blind to be collapsed upward and stretched downward normally.

1 . An equilibrium device for a blind without pull cords comprising an upper rod, said upper rod installed with at least one elastic force mechanism in the interior, a blind assembled under said upper rod and having a plurality of linking cords longitudinally threaded therethrough, the elastic force of said elastic force mechanism and the weight of said blind maintained in a force balanced condition, said blind able to be stretched downward or collapsed upward at a required level: and characterized by, 
 A lower rod assembled at the underside of said blind: and    At least one weight-balancing member movably installed at a proper location in the interior of said lower rod, said weight-balancing member employed for increasing and adjusting the weight of said blind after said blind is cut in width and lightened, said weight-balancing member enabling the weight of said blind kept at a force-balanced condition with the elastic force of said elastic force mechanism.    
     
     
         2 . The equilibrium device for a blind without pull cords as claimed in  claim 1 , wherein said lower rod has its topside formed with a transverse slide groove for receiving therein the lowermost slat of said blind, and said weight-balancing member is to be fixed on the underside of said lowermost slat of said blind, said weight-balancing together with said lowermost slat of said blind slidably positioned in said transverse slide groove of said lower rod.  
     
     
         3 . The equilibrium device for a blind without pull cords as claimed in  claim 2 , wherein said blind is a honeycomb blind having its lowermost slat slidably positioned in said transverse slide groove of said lower rod, and said weight-balancing member is fixed on the underside of said lowermost slat of said honeycomb blind.  
     
     
         4 . The equilibrium device for a blind without pull cords as claimed in  claim 2 , said blind is a Venetian blind having its lowermost slat slidably received in said transverse slide groove of said lower rod, and said weight-balancing member is fixed on the underside of said lowermost slat of said Venetian blind.  
     
     
         5 . The equilibrium device for a blind without pull cords as claimed in  claim 2 , wherein said lower rod has its lower side bored with a transverse through slot having its opposite ends respectively fitted with a sealing cover for holding and caging the opposite lower sides of said blind.  
     
     
         6 . The equilibrium device for a blind without pull cords as claimed in  claim 1 , wherein a winding shaft is assembled between said elastic force mechanism and said linking cords so that the elastic torsion of said elastic force mechanism can actuate said linking cords to draw upward said blind through said winding shaft.