Pull Cord Mechanism for a Window Shade

Abstract

A pull cord mechanism for a window shade includes a frame ( 1 ), a shade ( 2 ), a shade driving mechanism ( 3 ), and a pull cord ( 4 ) for driving the shade driving mechanism ( 3 ). The shade driving mechanism ( 3 ) is fixed to the frame 1 and drives the shade ( 2 ) to fold and unfold. A barrel ( 5 ) is mounted to the frame ( 1 ) at a location corresponding to the pull cord ( 4 ). The barrel ( 5 ) includes a peripheral wall having a slit ( 7 ) extending in an axial direction. A sliding block ( 8 ) is slideably received in the barrel ( 5 ). A handle ( 9 ) is mounted to an outer periphery of the peripheral wall of the barrel ( 5 ). The sliding block ( 8 ) is connected to the handle ( 9 ) by a link ( 10 ) extending through the slit ( 7 ). The pull cord ( 4 ) is received in the barrel ( 5 ). The sliding block ( 8 ) is fixed to the pull cord ( 4 ) in the barrel ( 5 ).

1 . A pull cord mechanism for a window shade comprising a frame, a shade, a shade driving mechanism, and a pull cord for driving the shade driving mechanism, with the shade driving mechanism fixed to the frame, with the shade driving mechanism driving the shade to fold and unfold, the improvements comprising: a barrel mounted to the frame at a location corresponding to the pull cord, with the barrel including a peripheral wall having a slit extending in an axial direction, with a sliding block slideably received in the barrel, with a handle mounted to an outer periphery of the peripheral wall of the barrel, with the sliding block connected to the handle by a link extending through the slit, with the pull cord received in the barrel, with the sliding block fixed to the pull cord in the barrel. 
     
     
         2 . The pull cord mechanism for a window shade as claimed in  claim 1 , with the barrel having a tail end, with an end cap mounted to the tail end of the barrel. 
     
     
         3 . The pull cord mechanism for a window shade as claimed in  claim 1 , with the handle being a sleeve having a hole, with the hole having a shape of cross sections corresponding to that of cross sections of the barrel. 
     
     
         4 . The pull cord mechanism for a window shade as claimed in  claim 3 , with the shape of the cross sections of the barrel being one of square, rectangular, circular, elliptic, polygonal, and plum blossom-shaped. 
     
     
         5 . The pull cord mechanism for a window shade as claimed in  claim 4 , with the hole of the barrel being cylindrical, with the sliding block including two ends each having an end face, with each of the end faces of the sliding block having a curve corresponding to that of the inner periphery of the hole of the barrel. 
     
     
         6 . The pull cord mechanism for a window shade as claimed in  claim 1 , with the pull cord extending through a center of the sliding block and fixed to the sliding block. 
     
     
         7 . The pull cord mechanism for a window shade as claimed in  claim 3 , with the sleeve made of plastic or aluminum alloy, with the sliding block made of plastic or aluminum alloy, with the sleeve, the sliding block, and the link integrally formed of plastic by injection molding or integrally formed by processing aluminum alloy. 
     
     
         8 . The pull cord mechanism for a window shade as claimed in  claim 7 , with the barrel made of aluminum alloy or plastic.