Patent Publication Number: US-2011056633-A1

Title: Safety buckle for a window blind assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a safety buckle for a window blind assembly, more particularly to a safety buckle that is mounted on a window blind assembly and that is configured to allow a pull cord unit of the window blind assembly extending therethrough to escape therefrom. 
     2. Description of the Related Art 
     Referring to  FIG. 1 , a conventional window blind assembly is exemplified as a roman blind  1  that includes a top rail  11  adapted to be disposed at a top edge of a window, a drawable light-blocking curtain  12  hung from the top rail  11 , a plurality of buckles  13  disposed at a rear side of the light-blocking curtain  12 , and a pull cord  14  fixedly connected to a lower section  121  of the light-blocking curtain  12  for drawing up and lowering the light-blocking curtain  12 . The buckles  13  are vertically spaced apart from each other, and the pull cord  14  vertically extends through each of the buckles  13 . 
     However, such an arrangement is dangerous for children playing with the roman blind  1 . It is possible that a child extends his/her neck between the light-blocking curtain  12  and the pull cord  14  when playing with the roman blind  1 , and it may be difficult for the child to escape when the child&#39;s neck is restricted therebetween. 
     SUMMARY OF THE INVENTION 
     Therefore, an object of the present invention is to provide a safety buckle for a window blind assembly that can alleviate accidental strangulation. 
     According to the present invention, a safety buckle for a window blind assembly comprises a connecting part, a bar section, and a pair of surrounding arms. The window blind assembly includes a top rail, a drawable light-blocking unit hung from the top rail, and a pull cord unit for drawing up and lowering the drawable light-blocking unit. 
     The connecting part is adapted for mounting on one side of the light-blocking unit of the window blind assembly. The connecting part has two ends spaced apart from each other in a longitudinal direction. The bar section extends along the longitudinal direction and is connected to the two ends of the connecting part. Each of the surrounding arms extends along an arc from a corresponding one of the ends of the connecting part toward another one of the ends of the connecting part. The surrounding arms cooperate with the bar section to define a buckle hole that is adapted for extension of the pull cord unit of the window blind assembly therethrough. 
     The surrounding arms define an escape path therebetween that is in spatial communication with the buckle hole, and are configured to allow the pull cord unit to escape from the buckle hole into the escape path when the pull cord unit is subjected to a pulling force in a transverse direction that is transverse to the longitudinal direction and that is away from the bar section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which: 
         FIG. 1  is a perspective view of a conventional roman blind; 
         FIG. 2  is a perspective view of a window blind assembly provided with safety buckles of the preferred embodiment of the present invention; 
         FIG. 3  is a perspective view of the safety buckle of the preferred embodiment mounted on a curtain of the window blind assembly; 
         FIG. 4  is a top view of the safety buckle of the preferred embodiment; 
         FIG. 5  is a side view of the safety buckle of the preferred embodiment mounted on the curtain of the window blind assembly; 
         FIG. 6  is a perspective view similar to  FIG. 3  for illustrating a child extending his/her neck between the curtain and a pull cord unit of the window blind assembly; 
         FIG. 7  is a top view similar to  FIG. 4  for illustrating the pull cord unit escaping from a buckle hole into an escape path of the safety buckle of the preferred embodiment; and 
         FIG. 8  is a top view similar to  FIG. 7  for illustrating the pull cord escaping from the escape path. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 2 to 4 , the preferred embodiment of a safety buckle  4  of the present invention is disposed at a window blind assembly  3 . The window blind assembly  3  includes a top rail  31 , a drawable light-blocking unit  32  hung from the top rail  31 , and a pull cord unit  33  for drawing up and lowering the drawable light-blocking unit  32 . The drawable light-blocking unit  32  includes a curtain  321 , and a pair of connecting straps  322  disposed at a rear side of the curtain  321  and spaced apart from each other in a right-left direction. The pull cord unit  33  includes two pull cords  331  extending downwardly from the top rail  31  and connected to a lower section  323  of the curtain  321 . Since the structure of the window blind assembly  3  is well known to those skilled in the art and since the feature of this invention does not reside therein, further details thereof will be omitted herein for the sake of brevity. 
     It should be noted that there are two safety buckles  4  attached to the connecting straps  322  of the light-blocking unit  32  of the window blind assembly  3 , respectively. In other embodiments, the safety buckles  4  and corresponding connecting straps  322  may be more than two in number. Each of the safety buckles  4  includes a connecting part  412 , a bar section  411 , and a pair of surrounding arms  42 . 
     The connecting part  412  is attached to the corresponding one of the connecting straps  322 , and has two ends  413  spaced apart from each other in a longitudinal direction (i.e., a right-left direction). In this embodiment, the connecting part  412  is semi-circular in shape. The bar section  411  extends along the longitudinal direction, and is connected to the two ends  413  of the connecting part  412 . 
     Each of the surrounding arms  42  extends along an arc from a corresponding one of the ends  413  of the connecting part  412  toward another one of the ends  413  of the connecting part  412 . Each of the surrounding arms  42  includes a connecting section  421  extending from the corresponding one of the ends  413  of the connecting part  412 , and a plate section  422  extending from the connecting section  421  toward another one of the ends  413  of the connecting part  412 . For each of the surrounding arms  42 , the plate section  422  includes a connecting end  423  connected to the connecting section  421  of the corresponding one of the surrounding arms  42 , and a free end  424 . Specifically, the plate section  422  has a thickness smaller than that of the connecting section  421 . The surrounding arms  42  cooperate with the bar section  411  to define a buckle hole  43  for extension of a corresponding one of the pull cords  331  of the pull cord unit  33  of the window blind assembly  3  therethrough. 
     The plate sections  422  are radially spaced apart from each other, and cooperate to define an escape path  44  therebetween that is in spatial communication with the buckle hole  43 . For each of the plate sections  422 , the free end  424  is distal from the connection section  421  of a corresponding one of the surrounding arms  42 , and is spaced apart from the connecting section  421  of another one of the surrounding arms  42  to define an access  441  of the escape path  44 . Such configuration of the surrounding arms  42  allows the pull cord unit  33  to escape from the buckle hole  43  into the escape path  44  when the pull cord  331  is subjected to a pulling force in a transverse direction that is transverse to the longitudinal direction and that is away from the bar section  411 . 
     In this embodiment, the safety buckles  4  are generally circular in shape, and the connecting part  412  and the buckle hole  43  are generally semi-circular in shape. Each of the connecting sections  421  of the surrounding arms  42  subtends an arc length of about 50 degrees, and each of the plate sections  422  subtends an arc length of about 70 degrees. It is noted that the actual configuration of the safety buckles  4  may vary in other embodiments of the invention. 
     Referring to  FIGS. 5 and 6 , there is a space  34  between each of the pull cords  331  and the curtain  321 . When a child plays with the window blind assembly  3 , it is possible that the child extends his/her neck into the space  34  and is restricted therein as shown in  FIG. 6 . When the child struggles to free himself/herself, the pull cord  331  is subjected to the pulling force, and a moving direction of the pull cord  331  is limited by the bar section  411 , i.e., movement of the pull cord  331  toward the curtain  321  is limited by the bar section  411 . The pull cord  331  can escape from the buckle hole  43  into the escape path  44 , and can further escape from the escape path  44  through the accesses  441  thereof. The space  34  is widened, and makes it easier for the child to free his/her neck, thereby alleviating accidental strangulation. Moreover, the plate sections  422  of the surrounding arms  42  can deform outwardly or even break as shown in  FIGS. 7 and 8  when the pulling force is sufficiently strong, such that the pull cord  331  can also escape from the safety buckles  4 . 
     While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.