Patent Publication Number: US-2016222716-A1

Title: Multi-stage vertical open/close-type screen door operated by moving pulley

Description:
TECHNICAL FIELD 
     The present invention relates to a screen door of a platform, and more particularly, a technology relating to a screen door that is opened and closed in a vertical direction. 
     BACKGROUND ART 
     Passengers waiting on the platform for the train may drop to a railroad or be bumped to the moving train. To solve the foregoing problem, a platform screen door that is vertically opened and closed may be installed between the platform and the railroad. In this specification, the “platform screen door” may be called a screen door, a platform safety device, a platform safety door, or a platform screen device. 
     A technology relating to a vertical open/close-type platform screen door is published in Korean Patent Registration No. 10-0601112. The platform screen door according to the foregoing technology includes a plurality of main bodies installed on both ends of a platform, a screen door vertically moved along the main bodies, and a driver for vertically moving the screen door. Here, the screen door has a shape that lengthily extends in a left/right direction. Also, the screen door may be constituted by a plurality of doors including a first door extending in the left/right direction and a second door disposed on a lower or upper portion of the first door to extend in the left/right direction. The vertical open/close-type platform screen door may be used for a platform at which various kinds of trains stop. 
     However, when the method disclosed in the foregoing registration patent is used, the upper door may be caught by the lower door to ascend. Thus, an impact may occur at a moment at which the two doors that are vertically adjacent to each other collide with each other. Also, since the two doors are driven by separate driving members, a driving assembly may be complicated. 
     DISCLOSURE OF THE INVENTION 
     Technical Problem 
     The present invention is to provide a technology in which two screen doors are continuously and vertically moved without generating an impact therebetween in a vertical open/close-type platform screen door including the two screen doors that are vertically adjacent to each other. 
     Technical Solution 
     To solve the foregoing object, a platform screen door according to one aspect of the present invention includes: a main body including a pair of vertical frames ( 100 ,  200 ); a first door ( 30 ) and a second door ( 20 ), which are disposed between the pair of vertical frames; a moving pulley ( 3191 ) coupled to the second door to vertically move the second door; a first connector ( 3019 ) driving the moving pulley; and a driving assembly ( 4100 ) driving the first connector, the driving assembly being installed on the main body, wherein the first door is fixed and connected to one spot of the driving assembly of the first connector. 
     Here, the platform screen door may further include a first pulley ( 3192 ). Also, the first pulley may be rotatably coupled to the second door, and the first connector may include a belt for connecting the moving pulley to the first pulley. 
     Here, the second door may receive vertical force from the first door through the moving pulley. 
     Here, the first door and the second door may be moved along a rail provided on the vertical frame. 
     Here, the platform screen door may further include: a horizontal frame ( 300 ) disposed on upper portions of the pair of vertical frames; and one driving part installed on the main body to drive the driving assembly through the horizontal connector ( 302 ). Also, the driving assembly may include: a left driving assembly installed on a left vertical frame ( 100 ) of the pair of vertical frames to vertically move a left end of the first door; and a right driving assembly installed on a right vertical frame of the pair of vertical frames to vertically move a right end of the first door. Also, the left driving assembly and the right driving assembly may be driven at the same time by the one driving part. 
     Here, the horizontal connector may include a belt, a chain, or a rope and is disposed to extend along the horizontal frame, and a pulley ( 1042 ) for preventing the horizontal connector from drooping may be installed on the horizontal frame. 
     Here, the driving assembly may include: a pair of pulleys ( 142 ,  143 ); a vertical connector ( 144 ) rotated by the pair of pulleys; a first slit ( 31 ) defined in the vertical frame; and a first block ( 32 ) for fixing and coupling a portion of the vertical connector to the first door, the first block being vertically moved along the first slit. 
     Here, a rotation shaft ( 130 ) of the upper pulley ( 142 ) of the pair of pulleys may be coupled to the horizontal connector so as to be rotated by the horizontal connector. 
     Here, the platform screen door may further include: a first block ( 32 ) connected to left and right sides of the first door; and a second block ( 22 ) connected to left and right sides of the second door, the second block including a first moving pulley. Also, the first connector may transmit vertical force from the first block to the second block through the moving pulley. 
     Here, a first coupling part ( 3193 ) disposed on the first block may be fixed and coupled to a portion of the first connector. 
     Here, the left driving assembly may include: a left vertical connector ( 144 ); and a left first block ( 32 ) for fixing and coupling a portion of the left vertical connector to the left end of the first door. Also, the right driving assembly may include: a right vertical connector; and a right first block for fixing and coupling a portion of the right vertical connector to the right end of the first door. Also, the left end of the first door may be fixed and coupled to a first spot of the left vertical connector, and the right end of the first door may be fixed and coupled to a second spot of the right vertical connector. Also, the first and second spots may be selected to be always directed in the same direction. 
     Here, all of the left driving assembly and the right driving assembly may be disposed on a side of a platform or a side of a railroad. 
     Here, the platform screen door may further include: a third door ( 10 ) disposed between the pair of vertical frames; a pair of second pulleys ( 132 ,  133 ) installed on the pair of vertical frames; and a second vertical connector ( 134 ) rotated by the pair of second pulleys. Also, when the platform screen door is closed, the third door may be disposed at a position higher than that of the second door. Also, a first portion of the third door may be relatively fixed to a first portion of the second vertical connector so as to be vertically moved according to rotation of the second vertical connector. 
     A platform screen door according to another aspect of the present invention includes: first, second, and third doors disposed between a pair of vertical frames; first, second, and third hangers respectively connected to left and side sides of the first, second, and third doors; a first moving pulley coupled to the second hanger to vertically move the second door; a second moving pulley coupled to the third hanger to vertically move the third door; and first and second connectors for respectively driving the first and second moving pulleys. Here, the first hanger may be fixed and coupled to one spot of a first driving segment of the first connector, and the second hanger may be fixed and coupled to one spot of a second driving segment of the second connector. 
     Here, the platform screen door may further include a first pulley. Also, the first pulley may be rotatably coupled to the second hanger. Also, the first connector may be a belt for connecting the first moving pulley to the first pulley. 
     Here, the platform screen door may further include a second pulley. Also, the second pulley may be rotatably coupled to the third hanger. Also, the second connector may be a belt for connecting the second moving pulley to the second pulley. 
     Here, a first coupling part disposed on the first hanger may be fixed and coupled to a portion of the first connector, and a second coupling part disposed on the third hanger may be fixed and coupled to a portion of the second connector. 
     Here, the first hanger, the second hanger, and the third hanger may be moved along rails provided on the vertical frame. 
     Advantageous Effects 
     According to the present invention, in the vertical open/close-type platform screen door including the two screen doors that are vertically adjacent to each other, the two screen doors may be connected to each other by using the moving pulley to continuously and vertically move the two screen doors without generating the impact therebetween. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a platform screen door according to Embodiment 1 of the present invention. 
         FIG. 2  is a partial enlarged view of a portion A of  FIG. 1 . 
         FIG. 3  is a partial enlarged view of a portion B of  FIG. 1 . 
         FIG. 4  is an enlarged view of a hanger of  FIG. 1 . 
         FIG. 5  is a view illustrating a state in which the plurality of hangers of  FIG. 1  are arranged in parallel. 
         FIG. 6  is a partial enlarged view of a portion C of  FIG. 1 . 
         FIG. 7  is an exploded perspective view of a platform screen door according to Embodiment 2 of the present invention. 
         FIG. 8  is a partial enlarged view of a portion D of  FIG. 7 . 
         FIG. 9  is a view for explaining a structure of a hanger of  FIG. 7 . 
         FIG. 10  is an enlarged view for explaining a state in which the plurality of hangers of  FIG. 7  are coupled to be vertically spaced a predetermined distance from each other. Here,  FIG. 10 a    illustrates a structure before the plurality of hangers are coupled to each other, and  FIG. 10 b    illustrates a structure after the plurality of hangers are coupled to each other. 
         FIG. 11  is a view for explaining a structure in which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  are coupled to each other. 
         FIG. 12  is a view illustrating a state in which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  overlap each other. 
         FIG. 13  is a view illustrating a state in which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  are vertically spaced a predetermined distance from each other. 
         FIG. 14  is a front view of a platform screen door according to Embodiment 3 of the present invention. 
         FIG. 15  is a bottom view of a platform screen door according to an embodiment of the present invention. 
         FIG. 16 a    is a partial enlarged perspective view of a left frame  100  of  FIG. 14 . 
         FIG. 16 a    is a partial perspective view of the left frame  100  of  FIG. 14 . 
       FIG. is a view of a structure of a side that is opposite to  FIG. 16   b.    
         FIG. 16 d    is a view illustrating a mutual connection relationship between three blocks supporting doors of  FIG. 14 . 
         FIG. 17  is a view illustrating portions of an upper end of the left frame  100  and a connection part of a horizontal frame  300  of  FIG. 14 . 
         FIG. 18 a    is a view of a second door  20  and a third door  30  of  FIG. 14 . 
         FIG. 18 b    is a detailed view of the second door  20  of  FIG. 14 . 
         FIG. 18 c    is a detailed view of the third door  30  of  FIG. 14 . 
         FIG. 18 d    is a cross-sectional view of a holder part  310  of  FIG. 18   c.    
         FIG. 18 e    is a front view of the holder part  310  of  FIG. 18   c.    
         FIG. 19  is a view illustrating an inner structure of a lower block  31  of  FIG. 16   a.    
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. Also, for convenience of description, the dimensions of elements are exaggerated or downscaled. 
     Embodiment 1 
     Hereinafter, Embodiment 1 of the present invention will be described with reference to  FIGS. 1 to 6 . 
       FIG. 1  is an exploded perspective view of a platform screen door  1100  according to Embodiment 1 of the present invention. 
       FIG. 2  is a partial enlarged view of a portion A of  FIG. 1 . 
       FIG. 3  is a partial enlarged view of a portion B of  FIG. 1 . 
       FIG. 4  is an enlarged view of a plurality of hangers  1071 ,  1072 , and  1073  of  FIG. 1 . 
       FIG. 5  is a view illustrating a state in which the plurality of hangers  1071 ,  1072 , and  1073  of  FIG. 1  are arranged in parallel. 
       FIG. 8  is a partial enlarged view of a portion C of  FIG. 1 . 
     Hereinafter, the platform screen door  1100  according to Embodiment 1 of the present invention will be described with reference to  FIGS. 1 to 5 . 
     In the platform screen door  1100  according to Embodiment 1 of the present invention, a basic frame of the platform screen door  1100  includes a pair of vertical frames  1010  installed to be spaced apart from each other on a platform and two horizontal frames  1020  connecting upper ends of the pair of vertical frames  1010  to each other. The horizontal frames  1020  and the pair of vertical frames  1010  may be connected to each other by a connection reinforcing member  1021 . 
     A torsion bracket  1031 , a belt drooping prevention bracket  1041 , and a driving part  1030  are fixedly installed on the horizontal frames  1020 . The driving part  1030  may be coupled to a horizontal belt  1040  to rotate the horizontal belt  1040  in a clockwise or counterclockwise direction. Pulleys  1032  and  1042  may be installed to maintain tension of the horizontal belt  1040 . The horizontal belt  1040  may rotate a rotation shaft to which the pulley  1051  is fixedly coupled and thus rotates the pulley  1051 . In this specification, the horizontal belt  1040  may be substituted by a chain. The ‘horizontal belt’ or ‘chain’ may be commonly called a ‘horizontal connector’. 
     A pair of pulleys  1051  installed on one vertical frame  1010  is divided into an upper pulley  1051  and a lower pulley  1051 . The vertical belt  1050  may be rotated in the clockwise or counterclockwise direction by the pair of pulleys  1051 . That is, the moving direction of the vertical belt  1050  may be determined by the operation of the driving part  1030 . Here, the vertical belt  1050  is constituted by a belt. On the other hand, the belt may be substituted by a chain or rope. In this specification, the vertical belt  1050  lengthily installed on the vertical frame  1010  in a vertical direction and the chain or rope that is an equivalent substitution component may be commonly called a ‘vertical connector’. 
     A clamp  1052  may be fixed and coupled to one spot of the vertical belt  1050 . The clamp  1052  may be fixed and coupled to a clamp  1722  that is provided on a first hanger  1071  through a coupling piece  1522 . Thus, the vertical belt  1050  may be moved by the operation of the driving part  1030 , and the first hanger  1071  may be vertically moved by the same displacement as the one spot of the vertical belt  1050 . 
     A first rail  1061 , a second rail  1062 , and a third rail  1063  are disposed on the vertical frame  1010 . A first hanger  1071 , a second hanger  1072 , and a third hanger  1073  may be respectively coupled to the rail  1061 , the second rail  1062 , and the third rail  1063  and then be vertically moved. For this, at lest one roller  1055  may be coupled to each of the first hanger  1071 , the second hanger  1072 , and the third hanger  1073 , and a shaft of the roller  1055  may be coupled to a roller hole  1066 . In  FIG. 3 , rollers coupled to the second and third hangers  1072  and  1073  are not illustrated for convenience of description. 
     One left vertical frame  1010  and one right vertical frame  1010  may be coupled to each of the first hanger  1071 , the second hanger  1072 , and the third hanger  1073 . A first door  1081 , a second door  1082 , and a third door  1083  may be coupled between the pair of first hangers  1071 , between the pair of second hangers  1072 , and between the pair of third hangers  1073 , respectively. A door connection hole  1088  may be defined in each of the hanger  1071 , the second hanger  1072 , and the third hanger  1073 . Thus, each of the first door  1081 , the second door  1082 , and the third door  1083  may be coupled to the door connection hole  1088 . 
     A pulley shaft  1723  for a pulley  1091  may be disposed on each of upper and lower ends of the second hanger  1072 . The pair of pulleys  1091  may be rotatably coupled to the pair of pulley shafts  1723 . Also, a belt  1009  may be coupled to contact an outer surface of each of the pair of pulleys  1091 . In this specification, the belt  1009  may be called a ‘rotation connector’. Also, the ‘rotation connector’ may be substituted by a chain in addition to the belt. 
     A first coupling part  1092  may be disposed on an upper end of the first hanger  1072   m  and a third coupling part  1093  may be disposed on a lower end of the third hanger  1073 . The first coupling part  1092  may be fixed and coupled to one portion of the belt  1009 , and the third coupling part  1093  may be fixed and coupled to the other portion of the belt  1009 . 
     Hereinafter, movement principles of the hanger  1071 , the second hanger  1072 , and the third hanger  1073  according to the operation of the driving part  1030  will be described according to Embodiment 1 of the present invention. 
     When the driving  1030  is rotated, the horizontal belt  1040  is rotated in the clockwise (counterclockwise) direction. Thus, the pair of vertical belts  1050  coupled to the left vertical frame  1010  and the right vertical frame  1010  may also be rotated in the clockwise (counterclockwise) direction. The clamp  1052  fixed and coupled to the one spot of the vertical belt  1050  is moved along the vertical belt  1050 . The first hanger  1071  fixed and coupled to the clamp  1052  through the coupling piece  1522  and the clamp  1052  is moved in the same direction as the clamp  1052 . 
     Here, since the first coupling part  1092  of the first hanger  1071  and the belt  1009  are fixed and coupled to each other, the second hanger  1072  coupled to the belt  1009  through the pulley  1091  may be moved in the same direction as the first hanger  1071 . Here, since the pair of moved pulleys  1091  (particularly, the lower pulleys) serve as a moving pulley (i.e., movable pulley), a vertical moving speed of the second hanger  1072  may be a half of a vertical moving speed of the first hanger  1071 . Thus, when each of the first and second hangers  1071  and  1072  are disposed at the lowermost position, vertical central portions of the first and second hangers  1071  and  1072  are vertically spaced a predetermined distance from each other. Thus, as the first and second hangers  1071  and  1072  ascend upward, the distance between the vertical central portions may be reduced. 
     A first protrusion  1711  is disposed on the lower end of the first hanger  1071 . Since the first and second hangers  1071  and  1072  are coupled to each other by the above-described moving pulley, the first hanger  1071  may ascend or descend at a speed that is double that of the second hanger  1072 . Here, when the first protrusion  1711  is hung on the lower end of the second hanger  1072 , the first and second hangers  1071  and  1072  may ascend at the same speed. Thus, the first hanger  1071  does not ascend up to a height that is greater than that of the second hanger  1072 . 
     Also, a second protrusion  1721  is disposed on the lower end of the second hanger  1072 . When the second hanger  1072  ascends up to a predetermined height, the second protrusion  1721  is hung on the lower end of the third hanger  1073 . At this time, the third hanger  1073  may be coupled to the second hanger  1072  to ascend at the same speed as the second hanger  1072 . Before this, the third hanger  1073  may be maintained in a stop state. 
       FIG. 4  illustrates a state in which the first protrusion  1711  is hung on the lower end of the second hanger  1072 , and the second protrusion  1721  is hung on the lower end of the third hanger  1073 . At this time, the first hanger  1071 , the second hanger  1072 , and the third hanger  1073  may ascend in a mutually overlapping state. 
     On the other hand, when each of the first hanger  1071 , the second hanger  1072 , and the third hanger  1073  is disposed at the lowermost position, the first hanger  1071 , the second hanger  1072 , and the third hanger  1073  may be maintained to be vertically spaced a predetermined distance from each other. To provide the spaced state, a first stopper  1611  and a second stopper  1621  may be disposed on the first rail  1061  and the second rail  1062 , respectively. The lower end of the second hanger  1072  may be hung on the first stopper  1611  and thus not be moved downward from the first stopper  1611 , and the lower end of the third hanger  1073  may be hung on the second stopper  1621  and thus not be moved downward from the second stopper  1621 . 
     Then, when each of the first hanger  1071 , the second hanger  1072 , and the third hanger  1073  is disposed at the uppermost position, if the driving part  1030  is rotated in a reverse direction, the horizontal belt  1040  may be rotated in the counterclockwise (clockwise) direction. Thus, each of the first hanger  1071 , the second hanger  1072 , and the third hanger  1073  may be operated in the opposite way when ascending, thereby to descend. 
     The first door  1081 , the second door  1082 , and the third door  1083  are moved together with the first hanger  1071 , the second hanger  1072 , and the third hanger  1073 , respectively. 
     Hereinafter, constituents for allowing the left and right ends of each of the first door  1081 , the second door  1082 , and the third door  1083  to ascend or descend at the same time will be described. 
     To easily repairing and maintaining the platform screen door  1100  installed according to Embodiment 1 of the present invention, it is preferable that all of the pair of vertical belts  1050  are installed on a side of the platform or a side of the railroad. Here, as seen in  FIGS. 1, 3, and 6 , the horizontal belt  1040  and the pair of vertical belt  1050  are always rotated in the same direction. Thus, in the left vertical frame  1010  of  FIG. 3 , the clamp  1052  has to be fixed and coupled to an outer segment  1500  of two vertical segments of the vertical belt  1050  in an opposite direction (or in an outward direction of the outer segment  1500 ). Also, in the right vertical frame  1010  of  FIG. 6 , the clamp  1052  has to be fixed and coupled to the outer segment  1500  of the two vertical segments of the vertical belt  1050  in the outward direction (or a direction that is opposite to the outward direction of the outer segment  1500 ). In this specification, a portion of the left vertical belt  1050  (i.e., the left vertical connector) of the left vertical frame  10101 , at which the clamp  1052  is fixed and coupled may be called a ‘first spot’, and a portion of the right vertical belt  1050  (i.e., the right vertical connector) of the right vertical frame  1010 , at which the clamp  1052  is fixed and coupled may be called a ‘second spot’. 
     A housing  1090  of  FIG. 1  may serve as a protector for protecting the inner components of the vertical open/close-type platform screen door  1100  according to Embodiment 1. Here, a horizontally extending portion of the housing  1090  may be utilized as a space for advertisement. 
     Although a balance weight for compensating weights of the first, second, and third hangers  1071 ,  1072 , and  1073  and the first, second, and third doors  1081 ,  1082 , and  1083  is not illustrated in  FIGS. 1 to 6 , a balance weight as illustrated in  FIG. 1  may be installed. 
     In Embodiment 1 of the present invention, the third hanger  1073 , the third rail  1063 , and the third door  1083  may be omitted. In this case, the first hanger  1071  and the second hanger  1072  may not be changed in operation state. A portion of claims in this specification may include the contents according to the foregoing Embodiment. Among these, there may be a claim that sets forth the structure in which the third hanger  1073 , the third rail  1063 , and the third door  1083  are omitted. 
     Embodiment 2 
     Hereinafter, Embodiment 2 of the present invention will be described with reference to  FIGS. 2 to 13 . 
       FIG. 7  is an exploded perspective view of a platform screen door  2200  according to Embodiment 2 of the present invention. 
       FIG. 8  is a partial enlarged view of a portion D of  FIG. 7 . 
       FIG. 9  is a view for explaining a structure of a hanger of  FIG. 7 . 
       FIG. 10  is a view for explaining a structure in which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  are coupled to each other. Here,  FIG. 10 a    illustrates a structure before the plurality of hangers  2171 ,  2172 , and  2173  are coupled to each other, and  FIG. 10 b    illustrates a structure after the plurality of hangers  2171 ,  2172 , and  2173  are coupled to each other. 
       FIG. 11  is a view for explaining a spot at which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  are coupled to each other. 
       FIG. 12  is a view illustrating a state in which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  ascend to overlap each other. 
       FIG. 13  is a view illustrating a state in which the plurality of hangers  2171 ,  2172 , and  2173  of  FIG. 7  are vertically spaced a predetermined distance from each other. 
     Hereinafter, the platform screen door  2200  according to Embodiment 2 of the present invention will be described with reference to  FIGS. 7 to 13 . 
     When comparing the platform screen door  2200  of  FIG. 7  according to Embodiment 2 to the platform screen door  1100  of  FIG. 1  according to Embodiment 1, the platform screen door  2200  of  FIG. 7  may have the same structure as the platform screen door  1100  of  FIG. 1  except for a ‘portion D’. 
     In the platform screen door  2200  according to Embodiment 2 of the present invention, a basic frame of the platform screen door  2100  includes a pair of vertical frames  2110  installed to be spaced apart from each other on a platform and a horizontal frame  2120  connecting upper ends of the pair of vertical frames  2110  to each other. The horizontal frames  2120  and the pair of vertical frames  2110  may be connected to each other by a connection reinforcing member  2121 . Here, the pair of vertical frames  2110 , the horizontal frame  2120 , and the connection reinforcing member  2121  of  FIG. 7  may respectively correspond to the pair of vertical frame  1010 , the horizontal frame  1020 , and the connection reinforcing member  1021  of  FIG. 1 . Thus, their component, structure, and driving method may also be the same. For example, a torsion bracket  2131 , a belt drooping prevention bracket  2141 , and a driving part  2130 , which are fixed and installed on the horizontal frame  2120  may correspond to the torsion bracket  1031 , the belt drooping prevention bracket  1041 , and the driving part  1030  of  FIG. 1 , respectively. Also, a horizontal belt  2140 , pulleys  22132 ,  2142 , and  2151 , a vertical belt  2150 , and a clamp  2152  of  FIG. 7  may correspond to the horizontal belt  1040 , the pulleys  1032 ,  1042 , and  1051 , the vertical belt  1050 , and the clamp  1052  of  FIG. 1 , respectively. 
     Here, a first rail  2161 , a second rail  2162 , and a third rail  2163  are disposed on the vertical frame  2110 . A first hanger  2171 , a second hanger  2172 , and a third hanger  2173  may be respectively coupled to the rail  2161 , the second rail  2162 , and the third rail  2163  and then be vertically moved. For this, at lest one roller  2155  may be coupled to each of the first hanger  2171 , the second hanger  2172 , and the third hanger  2173 , and a shaft of the roller  2155  may be coupled to a roller hole  2166 . 
     One left vertical frame  2110  and one right vertical frame  2110  may be coupled to each of the first hanger  2171 , the second hanger  2172 , and the third hanger  2173 . A first door  2181 , a second door  2182 , and a third door  2183  may be coupled between the pair of first hangers  2171 , between the pair of second hangers  2172 , and between the pair of third hangers  2173 , respectively. 
     Here, at least one door connection hole  2188  may be defined in each of the hanger  2171 , the second hanger  2172 , and the third hanger  2173 . Thus, each of the first door  2181 , the second door  2182 , and the third door  2183  may be coupled to the door connection hole  2188  defined in each of the hanger  2171 , the second hanger  2172 , and the third hanger  2173 . 
     A pulley shaft  2723  for a pulley  2191  may be disposed on each of upper and lower ends of the second hanger  2172 . The pair of pulleys  2191  may be rotatably coupled to the pair of pulley shafts  2723 . Also, a belt  2019  may be coupled to contact an outer circumferential surface of each of the pair of pulleys  2191 . 
     A pulley shaft  2724  for a pulley  2195  may be disposed on each of upper and lower ends of the third hanger  2173 . The pair of pulleys  2195  may be rotatably coupled to the pair of pulley shafts  2724 . Also, a belt  2029  may be coupled to contact an outer circumferential surface of each of the pair of pulleys  2195 . 
     Here, in this specification, the upper pulleys  2191  and  2195  of the pair of pulleys  2191  and  2195  may be called ‘pulleys’, and the lower pulleys  2191  and  2195  may be called ‘moving pulleys’. 
     As illustrated in  FIGS. 10 a , 10 b   , and  11 , a first coupling part  2192  may be disposed on an upper end of the first hanger  2171 , a second coupling part  2193  may be disposed on an upper end of the second hanger  2172 , a third coupling part  2194  may be disposed on a lower end of the third hanger  2173 , and a fourth coupling part  2196  may be disposed on a portion of the vertical frame  2110 . Here, the first coupling part  2192  may be fixed and coupled to one portion of the belt  2019 , the second coupling part  2193  may be fixed and coupled to one portion of the belt  2029 , the third coupling part  2194  may be fixed and coupled to the other portion of the belt  2019 , and the fourth coupling part  2196  may be fixed and coupled to the other portion of the belt  2029 . 
     Hereinafter, movement principles of the hanger  2171 , the second hanger  2172 , and the third hanger  2173  according to the operation of the driving part  2130  will be described according to Embodiment 2 of the present invention. 
     When the driving  2130  is rotated, the horizontal belt  2140  is rotated in the clockwise (counterclockwise) direction. Thus, the pair of vertical belts  2150  coupled to the left vertical frame  2110  and the right vertical frame  2110  may also be rotated in the clockwise (counterclockwise) direction. The clamp  2152  fixed and coupled to the vertical belt  2150  is moved along the vertical belt  2150 . The first hanger  2171  fixed and coupled to the clamp  2152  through the coupling piece  2522  and the clamp  2722  is moved in the same direction as the clamp  2152 . 
     Here, since the first coupling part  2192  of the first hanger  2171  is fixed and coupled to one portion of the belt  2019 , the second coupling part  2193  of the second hanger  2172  is fixed and coupled to the belt  2029 , third coupling part  2194  of the third hanger  2173  is fixed and coupled to the other portion of the belt  2019 , the second hanger  2172  coupled to the belt  2019  through the pulley  2191  and the third hanger  2173  coupled to the belt  2029  through the pulley  2195  may be moved in the same direction as the first hanger  2171 . Here, since the pair of pulleys  2191  and the other pair of pulleys  2195  serve as moving pulleys (i.e., movable pulleys), a vertical moving speed of the first hanger  2171 , a vertical moving speed of the second hanger  2172 , and a vertical moving speed of the third hanger  2173  may have a ratio of 3:2:1. Here, the lower pulley  2191  of the pair of pulleys  2191  and the lower pulley  2195  of the other pair of pulleys  2195  may serve as the moving pulleys. Thus, when each of the first, second, and the third hangers  2171 ,  2172 , and  2173  are disposed at the lowermost position, vertical central portions of the first, second, and third hangers  2171 ,  2172 , and  2173  are vertically spaced a predetermined distance from each other. Thus, as the first, second, and third hangers  2171 ,  2172 , and  2173  ascend upward, the distance between the vertical central portions may be reduced. 
     A first protrusion  2711  is disposed on the lower end of the first hanger  2171 . Since the first and second hangers  2171  and  2172  are coupled to each other by the above-described moving pulley (e.g., the pulley  2191 ), the first hanger  2171  may ascend or descend at a speed that is 3/2 times that of the second hanger  2172 . Here, when the first protrusion  2711  is hung on the lower end of the second hanger  2172 , the first and second hangers  2171  and  2172  may ascend at the same speed. Thus, the first hanger  2171  does not ascend up to a height that is greater than that of the second hanger  2172 . 
     Also, a second protrusion  2721  is disposed on the lower end of the second hanger  2172 . When the second hanger  2172  ascends up to a predetermined height, the second protrusion  2721  is hung on the lower end of the third hanger  2173 . Here, the third hanger  2173  may be coupled to the second hanger  2172  to ascend at the same speed as the second hanger  2172 . 
       FIG. 12  illustrates a state in which the first protrusion  2711  is hung on the lower end of the second hanger  2172 , and the second protrusion  2721  is hung on the lower end of the third hanger  2172 . At this time, the first hanger  2171 , the second hanger  2172 , and the third hanger  2173  may ascend in a mutually overlapping state. 
     On the other hand, when each of the first hanger  2171 , the second hanger  2172 , and the third hanger  2173  is disposed at the lowermost position, the first hanger  1071 , the second hanger  1072 , and the third hanger  1073  may be maintained to be vertically spaced a predetermined distance from each other as illustrated in  FIG. 13 . To provide the spaced state, a first stopper  2611  and a second stopper  2621  may be disposed on the first rail  2061  and the second rail  2062 , respectively. The lower end of the second hanger  2072  may be hung on the first stopper  2611  and thus not be moved downward from the first stopper  2611 , and the lower end of the third hanger  2073  may be hung on the second stopper  2621  and thus not be moved downward from the second stopper  2621 . 
     Then, when each of the first hanger  2171 , the second hanger  2172 , and the third hanger  2173  is disposed at the uppermost position, if the driving part  2130  is rotated in a reverse direction, the horizontal belt  2140  may be rotated in the counterclockwise (clockwise) direction. Thus, each of the first hanger  2171 , the second hanger  2172 , and the third hanger  2173  may be operated in the opposite way when ascending, thereby to descend. 
     The first door  2181 , the second door  2182 , and the third door  2183  are moved together with the first hanger  2171 , the second hanger  2172 , and the third hanger  2173 , respectively. 
     Embodiment 3 
     Hereinafter, a platform screen door according to Embodiment 3 of the present invention will be described with reference to  FIGS. 14 to 19 . 
       FIG. 14  is a front view of a platform screen door according to an embodiment of the present invention. 
     [Overall Configuration of Platform Screen Door] 
     Hereinafter, an overall configuration of the platform screen door according to Embodiment 3 of the present invention will be described with reference to  FIGS. 14 and 15 . 
     The platform screen door according to Embodiment 3 of the present invention may include first and second vertical frames  100  and  200  installed on a platform  500  and a horizontal frame  300  connecting upper ends of the first and second vertical frames  100  and  200  to each other. In this specification, the first vertical frame  100  may be called a ‘first frame’ or ‘left vertical frame’, and the second vertical frame  200  may be called a ‘second frame’ or ‘right vertical frame’. 
     A laser scan sensor  600  may be coupled to a lower end of a left side of the horizontal frame  300 . Also, three doors  10 ,  20 , and  30  may be movably and vertically coupled between the left frame  100  and the right frame  200 . 
     [Schematic Configuration of Three Doors] 
     Hereinafter, a schematic configuration of each of three doors according to Embodiment 3 of the present invention will be described with reference to  FIGS. 14, 18   a ,  18   b , and  18   c.    
     The third door  10  may have a plate shape. The third door  10  may include a pattern part  1005  for forming advertisement areas  1001  to  1004  and various shapes. Alternatively, the third door  10  may be formed of a finishing material such as glass and polycarbonate. In this specification, the ‘third door’ may be called an ‘upper door’. 
     A five-line rope  25  extending in a horizontal direction may be disposed on the second door  20 . Here, holder parts  210  and  220  may be fixed to both ends of the rope. In this specification, the ‘second door’ may be called an ‘intermediate door’. 
     In the first door  30 , a five-line rope  35  extending in the horizontal direction may be fixed to holder parts  310  and  320 . In this specification, the ‘first door’ may be called a ‘lower door’. 
     [Detailed Configuration of Each of Doors] 
     Hereinafter, when the first door  30  is described in more detail with reference to  FIGS. 18 c , 18 d , and 18 e   , an end of the rope  35  may be connected to a first coupling part  311  of the holder part  310 . Also, the holder part  310  and a first block  32  may be connected to each other through a second coupling part  312  of the holder part  310 . A protection cover  280  for protecting the portion for connecting the ropes  25  and  35  to the holder parts  210 ,  220 ,  310 , and  320  may be coupled to both ends of each of ropes. Also, an ultrasonic sensor  50  may be disposed on a sensor installation part  501  disposed on a lower end of each of the holder parts  310  and  320  of the first door  30 . 
     When comparing the second door  20  of  FIG. 18 b    to the first door  30 , the second door  20  may have the same structure as the first door  30  except that the sensor installation part  501  is not provided to the first door  30 . Thus, it may be understood that the second door  20  is constituted and installed through the same method as the first door  30 . 
     As illustrated in  FIG. 14 , although the third door  10  is different from the second door  20  and the first door  30  in that the third door  10  has a plate shape, but the rope shape, the third door  10  may have a shape similar to those of the second door  20  and the first door  30 . 
     [Description of Relative Positions According to Opening/Closing of Three Doors] 
     Hereinafter, relative positions of three doors according to opening/closing of the three doors will be described with reference to  FIG. 14 . 
     According to Embodiment 3 of the present invention, when the doors  10 ,  20 , and  30  are closed, the third door  10 , the second door  20 , and the first door  30  may be disposed in order from an upper side. Here, the lowermost rope of the second door  20  may overlap the uppermost rope of the first door  30 . 
     While the doors  10 ,  20 , and  30  are opened, the three doors may vertically ascend at the same time. Here, the three doors  10 ,  20 , and  30  may gradually overlap each other. When the doors are completely opened, the three doors may fully overlap each other. Here, in terms of a moving distance of each of the doors, a moving distance of the second door  20  may be less than that of the third door  10 , and a moving distance of the first door  30  may be greater than that of the second door  20 . 
     Detailed Description on Structure of Vertical Frame] 
     Hereinafter, a structure of the vertical frame will be described in detail with reference to  FIGS. 16 a , 16 b , 16 c   , and  17 . 
     A base part  191  of the left frame  100  may be directly fixed and connected to a platform  500 . A lower end of each of H-beams  198  and  199  may be fixed and coupled to the base part  191 . Also, an upper end of each of the H-beams  198  and  199  may be fixed and coupled to a housing  301  of the horizontal frame by connection pieces  192  and  193 . 
     A housing surrounding the H-beams  198  and  199  may include a housing front surface  151 , a housing rear surface  152 , a housing side surface  153 , a housing top surface  156 , and housing corners  154  and  155 . Here, the ‘housing’ may serve as a protection member for protecting inner components surrounded thereby. 
     Also, the H-beam  198  may be fixed and coupled to the housing front surface  151  by the connection piece  161 , and each of blocks  12 ,  22 , and  32  respectively connected to the first door  30 , the second door  20 , and the third door  10  may be fixed and coupled to a moving slit part  110 . 
     The slit part  110  may include three slits  11 ,  21 , and  31  that vertically and lengthily extend. The blocks  12 ,  22 , and  32  corresponding to the slits  11 ,  21 , and  31  may be movably coupled within the slits  11 ,  21 , and  31 , respectively. The slits  11 ,  21 , and  31  may have lengths different from each other. That is, the third slit  11  may have a length less than that of the second slit  21 , and the second slit  21  may have a length less than that of the first slit  13 . Also, upper ends of the first, second, and third slits  11 ,  21 , and  31  may be disposed at the same height. 
     Here, the third block  12  corresponding to the third slit  11  may be coupled to the upper door  10 , the second block  22  corresponding to the second slit  21  may be coupled to the intermediate door  20 , and the first block  32  corresponding to the first slit  31  may be coupled to the lower door  30 . 
     Holes  171  and  172  for supporting a rotation shaft  130  may be defined one spot of an upper end of the H-beam  199 . Here, a second pulley  132  may be rotatably coupled to the rotation shaft  130  on a front surface of the H-beam  199 . Also, a rotation shaft  131  may be installed on an intermediate end of the H-beam  199 , and a second pulley  133  may be rotatably coupled to the rotation shaft  131 . The second pulley  132  and the second pulley  133  may have the same diameter. Here, a second vertical connector (a second vertical belt)  134  may be coupled to the pair of second pulleys  132  and  133 . Also, one spot of the second vertical connector  134  may be fixed and connected to the third block (the upper block)  12 . 
     Here, the pulley  142  may be rotatably coupled to the rotation shaft  130  on a rear surface of the H-beam  199 . Also, a rotation shaft  141  may be installed on a lower end of the H-beam  199 , and a pulley  143  may be rotatably coupled to the rotation shaft  141 . The pulley  142  and the pulley  143  may have the same diameter. In an embodiment of the present invention, a circumferential length of the pulleys  142  and  143  may be three times of that of the second pulleys  132  and  133 . Here, a vertical connector (a vertical belt)  144  may be coupled to the pair of pulleys  142  and  143 . Also, one spot of the vertical connector  144  may be fixed and connected to the first block (the lower block)  32 . 
     [Movement Mechanism of First Block, Second Block, and Third Block] 
     Hereinafter, movement mechanism of the first block, the second block, and the third block will be described with reference to  FIGS. 16 b    and  16   c.    
     A movement principle of the second vertical connector  134  may be described as follows. First, the horizontal belt  302  may be rotated by an operation of a driving part (e.g., reference numeral  1030  of  FIG. 2 ) installed in the horizontal frame  300 . Here, the horizontal belt  302  may rotate the rotation shaft  130 . The rotation shaft  130  may rotate the second pulley  132 . The second pulley  132  may rotate the second vertical connector  134 . The second vertical connector  134  may rotate the second pulley  133 . When the one spot is vertically moved by the second vertical connector  134  connected to the third block  12 , the third block  12  may be vertically moved. 
     The first block  32  may be fixed and connected to the one spot of the vertical connector  144 . The first block  32  may be vertically moved according to the rotation of the vertical connector  144 . Here, the second pulley  132  and the pulley  142  may be connected to the same rotation shaft  130  and thus rotated at the same angular velocity. For example, when the second pulley  132  has a circumferential length that is ½ of that of the pulley  142 , a linear velocity of the second vertical connector  134  connected to the second pulley  132  may be ½ of that of the vertical connector  144  connected to the pulley  142 . 
     For example, in an embodiment, the first block  32 , the second block  22 , and the third block  12  may be moved by distances 1800 mm, 1350 mm, and 900 mm from the lowermost end that is fully closed to the uppermost end that is fully opened. 
     Here, referring to  FIG. 16 d   , the second block  22  may be connected the first block  32  through a moving pulley  3191 . The moving pulley  3191  and the first pulley  3192  are fixedly installed on the second block  22 , and the first connector (belt)  3019  is wound around the moving pulley  3191  and the first pulley  3192 . A portion (a first coupling part  3193 ) of the first block  32  may be fixed and coupled to one spot (that is expressed in a black circular shape) of the first connector  3019 , and a portion  3194  disposed on the third block  12  may be fixed and coupled to the other spot (that is expressed in a black diamond shape) of the first connector  3019 . Here, when the second vertical connector  144  vertically moves the first block  32 , the first block  32  may vertically move the second block  22  through the first connector  3019 . Here, for example, when the third block (the upper block) is vertically moved by a distance L, the second block (the intermediate block)  22  may be vertically moved by a distance 1.5 L. 
     In summary of the above-described movement mechanism, vertical moving speeds of the third block  12 , the second block  22 , and the first block  32  may be designed to have a ratio of 1:1.5:2. 
     Also, the third block  12 , the second block  22 , and the first block  32  may be guided and moved by a slit part  110  and a rail disposed on the rail part  120 . The rail part  120  may serve as a guide part along which a weight (not shown) is moved. 
     [Structures of First Block, Second Block, and Third Block] 
     Hereinafter, structures of the first block, the second block, and the third block will be described with reference to  FIG. 19 . Here, the structure of the first block will be mainly described as an example. 
       FIGS. 19( a ), 19( b ), and 19( c )  are plan, front, and side views of the first block  32 , respectively. 
     A hole  322  for supporting a rotation shaft  323  may be defined in the first block  32 .  FIG. 19  illustrates an example in which total 10 rotation shafts  323  and total 10 holes  322  are provided. The holes  322  may be provided for coupling a wheel  320 . Here, although the 10 holes  322  are defined in a vertical direction, reference numeral may be given to only one hole. 
     Also, the wheel  320  may be coupled to each of the rotation shafts  323  so that the wheel  320  is moved along the rail. Although all 10 wheels  320  are illustrated in  FIG. 18( c ) , for convenience of description, the wheels  320  may not illustrated or be expressed as a dotted line in  FIG. 19( b ) . 
     A coupling part  311  disposed on the first block  32  may be coupled to a coupling part  312  (see  FIG. 18 e   ) disposed on a holder part  310  of the first door  30  by using a coupling member. 
     Referring to  FIG. 19( a ) , the first block  32  may include a head part  1 , a body part  2 , a wheel  320  connected to an end of a left side of the body part  2 , and a belt connection part  321  connected to a center of an upper portion of the body part  2 . The belt connection part  321  may be fixed and coupled to one end of the above-described second vertical connector  134 . The head part  1  and the body part  2  may be integrated with each other. 
     The first block  32  may be coupled to the vertical frame through following processes. First, the body part  2  may be inserted into a first slit  31 . Here, the head part  1  may be hung on an edge of the first slit  31 . Then, the wheel  320  and the belt connection part  321  may be coupled to the body part  2 . Then, the belt connection part  321  may be fixed and coupled to the second vertical connector  134 . Here, the wheels  320  may be aligned to correspondingly contact the rail part  120 . 
     Here, the head part  1  may have a first width W 1  greater than a second width W 2  of the body part  2 . Also, the first width W 1  may be greater than a third width of the first slit, and the second width W 2  may be less than the third width. 
     [Description on Sensor Installed on Third Door] 
     As described above, a sensor  50  may be installed on a lower end of the first door  30 , i.e., a lower end of the holder part  310 . The sensor  50  may be provided in a pair on left and right sides. When the first door  30  descends, the sensor  50  may detect a person&#39;s head, which may exist directly under the first door  30 , to provide a signal for emergency stopping an operation of the screen door. For example, the sensor  50  may be an ultrasonic type sensor. Here, other technologies may be adopted as a specific detecting manner. 
     Here, the sensor  50  may be installed inside the first slit  31 , i.e., the vertical frame. On the other hand, the sensor may be installed outside the first slit  31 , i.e., the vertical frame. However, since dusts may be introduced into the vertical frame through the first slit  31 , it may be preferable that the first slit  31  has a small width. According to embodiments, a brush for preventing dusts from being introduced may be installed on the first slit  31 . 
     However, if the sensor  50  has a large size, when the sensor  50  is installed inside the first slit  31 , a signal to be transmitted from or received into the sensor  50  may be blocked by an edge portion of the first slit  31  because the first slit  31  has a narrow width. 
     Thus, in an embodiment of the present invention, for solving the above-described problem, the sensor  50  may be installed outside the first slit  31 , i.e., the vertical frame. 
     In the structure of the platform screen door according to an embodiment of the present invention, since the holder part  310  is disposed outside the first slit  31 , the sensor  50  may be installed on a sensor installation part  501  provided on a lower end of the holder part  310 . A wired cable connected to the sensor  50  may extend through the insides of the horizontal frame and the vertical frame of the platform screen door and be connected to a control part through the first slit  31 . 
     Embodiment 4 
     Hereinafter, a platform screen door according to Embodiment 4 of the present invention will be described with reference to  FIGS. 7 to 13 . 
     The platform screen door includes: a main body including a pair of vertical frames  2110 ; first and second doors  2181  and  2182  disposed between the pair of vertical frames  2110 ; a first moving pulley  2191  coupled to the second door  2182  to vertically move the second door  2182 ; a first connector  2019  for driving the first moving pulley  2191 ; and driving assemblies  1008  and  1009  installed on the main body to drive the first connector  2019 . Here, the first door  2181  may be fixed and coupled to one spot of a driving segment of the first connector  2019 . For example, the one spot of the driving segment of the first connector  2019  may represent a left portion of the first connector  2019 . 
     Here, the platform screen door according to Embodiment 4 of the present invention may further include a first pulley  2191 . The first pulley  2191  may be rotatably coupled to the second door  2181 . The first connector  2019  may be a belt for connecting the first moving pulley  2191  to the first pulley  2191 . Also, the second door  2182  may receive vertical force from the first door  2181  through the first moving pulley  2191 . Here, the first door  2181  and the second door  2182  may be moved along rails  2161  and  2162  provided on the vertical frame  2110 . 
     The platform screen door according to Embodiment 4 of the present invention may further includes: a horizontal frame disposed on upper portions of the pair of vertical frames  2110 ; and one driving part installed on the main body to drive the driving assemblies  1008  and  1009  through a horizontal connector  2140 . Here, the driving assembles  1008  and  1009  may include: a left driving assembly  1008  installed on a left vertical frame  2110  of the pair of vertical frames  2110  to vertically move a left end of the first door  2181 ; and a right driving assembly  1009  installed on a right vertical frame  2110  of the pair of vertical frames  2110  to vertically move a right end of the first door  2181 . Here, the left driving assembly  1008  and the right driving assembly  1009  may be driven at the same time by the one driving part. Here, the horizontal connector  2140  may include a belt, a chain, or a rope. The horizontal connector  2140  may be disposed to extend along the horizontal frame  2120 , and a pulley  1042  for preventing the horizontal connector  2140  from drooping may be installed on the horizontal frame  2120 . Here, the driving assemblies  1008  and  1009  may include a pair of pulleys  2151 , a vertical connector  2150  rotated by the pair of pulleys  2151 , a first rail  2161  disposed on the vertical frame, and a first hanger  2171  for fixing and coupling a portion of the vertical connector  2150  to the first door  2181  and vertically moved along the first rail  2161 . Here, a rotation shaft of the upper first pulley  2151  of the pair of pulleys  2151  may be coupled to the horizontal connector  2149  and thus rotated by the horizontal connector  2140 . 
     The platform screen door according to Embodiment 4 of the present invention may further include: a first hanger  2171  connected to a left side of the first door  2181 ; and a second hanger  2172  connected to a left side of the second door  2182  and including the first moving pulley. Here, the first connector  2019  may transmit the vertical force from the first hanger  2171  to the second hanger  2172  through the first moving pulley  2191 . Here, a first coupling part  2192  disposed on the first hanger  2171  may be fixed and coupled to a portion of the first connector  2019 . Here, the left driving assembly  1009  may include a left vertical connector  2150  and a left first hanger  2171  for fixing and coupling a portion of the left vertical connector  2150  to a left end of the first door  2181 . Also, the right driving assembly  1009  may include a right vertical connector  2150  and a right first hanger  2171  for fixing and coupling a portion of the right vertical connector  2150  to a right end of the first door  2181 . Here, the left end of the first door  2181  may be fixed and coupled to a first spot of the left vertical connector  2150 , and the right end of the first door  2181  may be fixed and coupled to a second spot of the right vertical connector  2150 . Here, the first spot and the second spot may be selected to be always directed in the same direction. Here, all of the left driving assembly  1008  and the right driving assembly  1009  may be disposed on a side of the platform or the railroad. 
     Embodiment 5 
     Hereinafter, a platform screen door according to Embodiment 5 of the present invention will be described with reference to  FIGS. 7 to 13 . 
     A platform screen door according to Embodiment 5 of the present invention includes: first, second, and third doors  2181 ,  2182 , and  2183  disposed between a pair of vertical frames  2110 ; first, second, and third hangers  2171 ,  2172 , and  2173  respectively connected to left and side sides of the first, second, and third doors  2181 ,  2182 , and  2183 ; a first moving pulley  2191  coupled to the second hanger  2172  to vertically move the second door  2182 ; a second moving pulley  2195  coupled to the third hanger  2173  to vertically move the third door  2183 ; and first and second connectors  2019  and  2029  for respectively driving the first and second moving pulleys  2191  and  2195 . 
     The first hanger  2171  may be fixed and coupled to one spot of the first driving segment of the first connector  2019 , and the second hanger  2172  may be fixed and coupled to one spot of the second driving segment of the second connector  2029 . For example, the one spot of the first driving segment of the first connector  2019  may represent a left portion of the first connector  2019 , and the one spot of the second driving segment of the second connector  2029  may represent a left portion of the second connector  2029 . 
     The platform screen door according to Embodiment 5 of the present invention may further include a first pulley  2191 . The first pulley  2172  may be rotatably coupled to the second hanger  2172 . The first connector  2019  may be a belt for connecting the first moving pulley  2191  to the first pulley  2191 . Also, the platform screen door according to Embodiment of the present invention may further include a second pulley  2195 . The second pulley  2195  may be rotatably coupled to the third hanger  2173 , and the second connector  2029  may be a belt for connecting the second moving pulley  2195  to the second pulley  2195 . 
     Here, a first coupling part  2192  disposed on the first hanger  2171  may be fixed and coupled to a portion of the first connector  2019 , and a second coupling part  2194  disposed on the third hanger  2173  may be fixed and coupled to a portion of the second connector  2029 . Here, the first hanger  2171 , the second hanger  2172 , and the third hanger  2173  may be moved along rails  2161 ,  2162 , and  2163  provided on the vertical frame  2110 . 
     Embodiment 6 
     Hereinafter, a platform screen door according to Embodiment 6 of the present invention will be described with reference to  FIGS. 14 to 19 . 
     The platform screen door according to Embodiment 6 includes: a main body including a pair of vertical frames  100  and  200 ; first and second doors  30  and  20  disposed between the pair of vertical frames  100  and  200 ; a moving pulley  3191  coupled to the second door  20  to vertically move the second door  20 ; a first connector  3019  for driving the moving pulley  3191 ; and a driving assembly  4100  installed on the main body to drive the first connector  3019 . Here, the first door  30  may be fixed and coupled to one spot of the driving assembly  4100  of the first connector  3019 . Here, the term ‘fixed and coupled’ may be concept including a structure in which the first door  30  is a portion of the driving assembly  4100 . 
     In this specification, the ‘horizontal connector’ and the ‘vertical connector’ may be called a ‘first connector’ and a ‘second connector’, respectively. Also, it may be unnecessary that the ‘horizontal connector’ has to lengthily extend in the horizontal direction, and the ‘vertical connector’ has to lengthily extend in the vertical direction. 
     In the above-described various embodiments, although each of the door leafs moved in the vertical direction has the plate shape or rope shape, the present embodiment is not limited thereto. For example, the door leafs may include at least one long rod that extends in the left/right direction. Also, each of the door leafs may be coupled to at least one structure such as the plate, the rope, and the rod. Also, a surface of each of the door leafs may be formed of a finishing material such as glass and polycarbonate. 
     The description of the present invention is intended to be illustrative, and those with ordinary skill in the technical field of the present invention pertains will be understood that the present invention can be carried out in other specific forms without changing the technical idea or essential features. Hence, the real protective scope of the present invention shall be determined by the technical scope of the accompanying claims. 
     DESCRIPTION OF SYMBOLS 
     FIGS.  14  to  19   
     
         
         
           
               10 : Third door  20 : Second door 
               30 : First door  11 : Third slit 
               21 : Second slit  31 : First slit 
               12 : Third block  22 : Second block 
               32 : First block  3193 : First coupling part 
               100 : Vertical frame (left side)  200 : Vertical frame (right side) 
               300 : Horizontal frame  302 : Horizontal connector 
               130 : Rotation shaft  142 ,  143 : Pulley 
               144 : Vertical connector, vertical belt  132 ,  133 : Second pulley 
               134 : Second vertical connector, second vertical belt  1030 : Driving part ( FIG. 2 ) 
               1042 : Pulley  3019 : First connector, belt 
               3191 : Moving pulley  3192 : First pulley 
               4100 : Driving assembly ( 32 ,  142 ,  143 ,  144 ,  130 ,  302 ,  1030 ) 
           
         
       
    
     FIGS.  1  to  13   
     
         
         
           
               1008 : Left driving assembly (Assembly of ( 1071 ,  1061 ,  1051 ,  1052 ,  1050 ,  1522 ) or ( 2171 ,  2161 ,  2151 ,  2152 ,  2150 ,  2522 )) 
               1009 : Right driving assembly ((Assembly of  1071 ,  1061 ,  1051 ,  1052 ,  1050 ,  1522 ) or ( 2171 ,  2161 ,  2151 ,  2152 ,  2150 ,  2522 ))