Patent Publication Number: US-2006011310-A1

Title: Automatic equalizer for blinds

Description:
FIELD OF THE INVENTION  
      The present invention relates to an automatic equalizer, more particularly to an automatic equalizer for blinds.  
     BACKGROUND OF THE INVENTION  
      The present invention relates to the technical area of automatic equalizers for blinds. With the special design of building thread holes on two arc grooves of an equalizer body in the same axial direction, a pulling string can pass and loop through the thread holes of the two arc grooves to equalize the pulling force of the pulling string and the vertical movement of the blinds. Since offices, homes, and restaurants install blinds onto windows for the purpose of decorating the interior, sheltering sunlight and protecting privacy. A blind is an accessory item for a building to shelter light and protect one&#39;s private activity from being peeped by others at will, and thus are extensively used. There are various kinds of blinds, and the common blind generally comprises several shutters connected sequentially one by one below an upper track, a lower track disposed at the bottom of the shutter, two parallel pulling strings disposed between each shutter and passing through an automatic stopper and vertically disposed at one side of the blind, and a pulling ring disposed at the end of the two pulling strings for synchronously control the two pulling strings such that each shutter can be pulled up and down steadily and synchronously.  
      However, the structure of the foregoing traditional pulling ring as shown in  FIG. 1  generally has a central penetrating hole at the center, and the hole allows the pulling string to pass through and to be tied at the rear end. If it is necessary to pull the pulling string to change the drooping length as the shutter are lifted or lowered. While the pulling string is pulled to change the drooping length, a user cannot move the shutters vertically up and down evenly (since the pulling force is not even, it is difficult to maintain a balanced vertical movement of the shutters as shown in  FIG. 2 ). Further, each pulling string is tied at a fixed end of the thread hole of the pulling ring, and it is easy for each pulling string to be tied at a point and thus tangles the string easily as shown in  FIG. 3 .  
     SUMMARY OF THE INVENTION  
      Since the design of the aforementioned blinds has the foregoing shortcoming on moving the shutters vertically up and down, an improvement on the pulling ring for a better application of the blinds is definitely required in order to equalize the pulling force of the pulling string and the vertical movement of the shutters.  
      Therefore, the inventor of the present invention based on years of experience on the design and manufacture of blinds to profoundly study the foregoing issue that the pulling ring cannot equalize the pulling force of the pulling string and the vertical movement of the shutters and aggressively find a solution by performing extensive researches and experiments, and finally invented an automatic equalizer for blinds that can equalize the pulling force of a pulling string and the vertical movements of the shutters.  
      The primary objective of the present invention is to provide an automatic equalizer for blinds that can equalize the pulling force of a pulling string and the vertical movement of the shutters. The equalizer body comprises two arc grooves disposed at the centre of one end of the equalizer body corresponding to a wavelike protrusion, a first and a forth thread holes and a second and a third thread holes being aligned parallel with each other in the same axial direction and disposed on a protruded end on the external side of one of the arc grooves and a protruded end on the internal side of the other arc groove respectively. The foregoing thread holes penetrate the other end of the equalizer body. With the thread holes of the two arc grooves for passing and looping the pulling string, the pulling string can be pulled two way for the looping, and the looped pulling string can be tied to a fixed end at the lower track of the blinds as to equalize the pulling force of the pulling string and the vertical movement of the shutters.  
      Another objective of the present invention is to provide an equalizer for passing and looping two pulling strings. Since the two arc grooves are disposed at one end of the equalizer body and a lid having an engaging member of the same shape is added, the bottom of the arc groove have partitions, and thus the thread holes are aligned parallel with each other in the same axial direction and will not coiled or tangled after the pulling string is passed.  
      A further objective of the present invention is to provide an equalizer that can adjust the pulling string and the fixed end disposed at the lower track of the shutters for tying each pulling string when the pulling force of the pulling string is uneven in order to facilitate equalizing the pulling force of the pulling string.  
      To make it easier for our examiner to understand the objective of the invention, its structure, innovative features, and performance, we use a preferred embodiment and the attached drawings for the detailed description of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of the pulling ring and blinds according to a prior art.  
       FIG. 2  is a front view of the pulling ring and blinds as depicted in  FIG. 1 .  
       FIG. 3  is a side view of the pulling string as depicted in  FIG. 1 .  
       FIG. 4A  is an exploded view of the equalizer body and the lid of the equalizer according to the present invention.  
       FIG. 4B  is a cross-sectional view of Section  4 B- 4 B of  FIG. 4A .  
       FIG. 5  is a perspective view of the equalizer body according to the present invention.  
       FIG. 6  is an illustrative view of the pulling string passing through the equalizer body according to the present invention.  
       FIG. 7  is an illustrative view of another pulling string passing through the equalizer body according to the present invention.  
       FIG. 8A  is a side view of the pulling string according to the present invention.  
       FIG. 8B  is an enlarged view of a section of the pulling string as depicted in  FIG. 8A .  
       FIG. 9  is an exploded view of the lid according to another preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The present invention discloses an automatic equalizer for blinds that can equalize the pulling force of a pulling string and the vertical movement of blinds.  
      Please refer to  FIG. 4A . A wavelike protrusion  102  partitioned by two arc grooves  10 ,  11  is disposed at the center of an end of an equalizer body  1 , a first and a fourth thread holes  100 ,  101  and a second and a third thread holes  110 ,  111  are parallel to each other along the same axial direction and disposed at a protruded end of the external side of one of the arc grooves  10  and the bottom of a protruded end of the internal side of the other arc groove  11 . The first, fourth, third and fourth thread holes  100 ,  101 ,  110 ,  111  penetrate the other end of the equalizer body  1 . A protruded circular rod  12  coupled to the two corresponding central positions has a through hole  120 . A buried hole  121  is disposed at the end of the through hole  120  for tying and fixing a pulling string  4  (As shown in  FIG. 5 ) in the buried hole  121 .  
      Two engaging members  130 ,  131  having the same shape as the two arc grooves  10 ,  11  are disposed on an end surface of the lid  13 . A wavelike groove  132  and its central hole  133  are disposed between the two engaging members  130 ,  131  for coupling the two engaging members  130 ,  131  into the arc grooves  10 ,  11  at one end of the equalizer body  1 .  
      Please refer to  FIGS. 4A and 4B  for the detailed structure of an automatic equalizer for blinds according to the preferred embodiment of the present invention. The equalizer body  1  comprises two arc grooves  10 ,  11  partitioned by a corresponding wavelike protrusion  102  disposed at the center of an end, and the bottom of the protruded ends on both sides of the arc grooves  10 ,  11  are disposed along the same axial direction and aligned parallel to the first and fourth thread holes  110 ,  111 . The aforementioned thread holes  100 ,  101 ,  110 ,  111  penetrate to another end of the equalizer body  1 , and the first, fourth, second and third thread holes  100 ,  101 ,  110 ,  111  disposed on the external and internal sides of the two arc grooves  10 ,  11  are provided to pass and loop the pulling strings  2 ,  3  (As shown in  FIG. 5 ) respectively to define a two-way corresponding winding mode, such that the looped pulling strings  2 ,  3  form a first knot  20 , a fourth knot  21  (As shown in  FIG. 6 ), a second knot  30  and a third knot  31  (As shown in  FIG. 7 ) at the lower track  50  of the shutters  5  as to achieve the effects of equalizing the pulling force of the pulling strings  2 ,  3  and the vertical movement of the shutters  5 .  
      Please refer to  FIG. 5  for the assembly adopted by this invention. The equalizer body  1  evacuates an arc groove  10 ,  11  at one end, and a first, a fourth, a second, and a third thread hole  100 ,  101 ,  110 ,  111  disposed at the bottom of the protruded end at the external and internal sides of the arc grooves  10 ,  11  along the same axial direction. A first knot  20  is tied at the lower track  50  along the external side of the pulling string  2  of the shutters  5  one by one first, and then passing the pulling string  2  through the shutter to the first thread hole  100  of its arc groove  10 , and then looping the pulling sting  2  to its fourth thread hole  101  corresponding to its arc groove  10 , and then coupled the internal side of the shutters and tie a fourth knot  21  at the lower track  50  as shown in  FIG. 6 .  
      Further, another pulling string  3  is tied at the lower track  50  to form a second knot  30  and passes through the internal side of the shutters  5  to the second thread hole  100  of another arc groove  11  and then looped to the corresponding thread hole  111  of another arc groove  11 , and finally coupled to the edge corresponding to the internal side of the shutter  5  and tied a third knot  31  at the lower track  50  as shown in  FIG. 7 .  
      Therefore, when the shutters  5  are pulled down, an initializing string  4  is pulled downward to drive the equalizer body  1  to move downward accordingly. If a force is applied onto the equalizer body  1 , then the shutters  5  are pulled downward. If the shutters  5  are found aslant, the knot at the inclined position is loosened to adjust the level of the shutters  5  to a horizontal level, and thus the user does not have to worry about the unbalanced force applied to the pulling strings  2 ,  3 . The vertical movement of the shutters  5  can be equalized. Therefore, the two pulling strings  2 ,  3  pass through the equalizer body  1  and then loop through the shutters  5 , such that the force exerted onto the internal and external sides of the shutters  5  corresponding to the pulling strings  2 ,  3  is even, and thus the pulling strings  2 ,  3  will not tangled to achieve the objective of preventing the occurrence of accidents and enhancing safety.  
      From the aforementioned structure, design and principle of motion as shown in  FIGS. 8A and 8B , it is known that the equalizer body  1  of the present invention comprises two arc grooves  10 ,  11  disposed on one end of the equalizer body  1 , a first and a four thread holes  100 ,  101  and a second and a third thread holes  100 ,  101  are disposed on the protruded end of the bottom of the two arc grooves  10 ,  11 , and the foregoing thread holes  100 ,  101 ,  110 ,  111  allow the two pulling strings  2 ,  3  to tie a first and a second knot  20 ,  30  at the lower track  50  and then to be passed and looped to the internal and external sides corresponding to a fourth and a third knot  21 ,  31 . Therefore, the equalizer body  1  can be used to achieve the effect of equalizing the pulling force of the pulling strings  2 ,  3  and the vertical movement of the shutters  5 .  
      Please refer to  FIG. 9 . A lid  13  of the invention could also be the lid  13   a  as shown in the figure. The lid  13   a  at an end surface comprises a first and a fourth thread holes  100 ,  101  and a second and a third thread holes  110 ,  111  being corresponsive to and equidistant from a circular rod  131   a.  Such arrangement also can achieve the purpose of covering and connecting the two arc grooves  10 ,  11  of the equalizer body  1 .