KR101841725B1

KR101841725B1 - Folding door structure

Info

Publication number: KR101841725B1
Application number: KR1020160030512A
Authority: KR
Inventors: 안중식
Original assignee: 안중식
Priority date: 2016-03-14
Filing date: 2016-03-14
Publication date: 2018-03-23
Also published as: KR20170106850A

Abstract

The present invention relates to a folding door structure in which a plurality of folding doors folded and folded along an outer frame forming an entrance of a building wall are individually folded. The folding door structure comprises an upper frame, a lower frame and a side frame, A door frame which is combined with the roller portion, the second roller portion and the third roller portion to facilitate rotation and movement, and which is in close contact with another adjacent folding door to maintain airtightness; A first roller unit coupled to the door frame for easy rotation and movement of the folding door so as to be movable and rotatable in the rail; A second roller unit installed on the door frame and coupled to the rail to facilitate movement of the folding door; And a third roller unit coupled to the door frame to facilitate rotation and movement of the folding door and being movable and rotatable in the rail. When opening any one of the folding doors, It is possible to open each folding door individually because the present invention can be opened individually.

Description

[0001] Folding door structure [

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a folding door structure, and more particularly, to a folding door structure in which a plurality of folding doors folded and slid along an outer frame forming an entrance of a building wall are individually folded.

Folding Door is a folding door that can be used for replacing the inner and outer walls of a building wall. It is durable in response to mechanical external force. It is also suitable for external use due to its soundproofing effect. In addition, glass can be applied to products to ensure visibility, and it is used as a folding door that has excellent design and is also good for interior use.

This folding door is designed to open up to 50% of the existing doors by more than 90% to utilize the design of the existing doors, making it easy for customers to access a wide living space for residential use, , And the entrance or exit of a shopping mall.

Generally, such a folding door is designed such that the door can be completely opened outside the entrance of the wall without any space for completely opening the door. It is possible to form an external frame along the doorway shape and to have a plurality of single individual doors The hinged door hinge is hinged by a hinge hinge and hinged so that one end of the hinge hinge is pivoted to one side of the door. When the folding door is pushed or pulled in the direction of the doorway, the door is folded and opened.

At this time, groove-shaped guide rails provided horizontally so as to be parallel to each other on the upper surface and the floor surface are provided on the outer frame forming the entrance, and each of the individual doors is installed on the guide rail, And a moving guide roller including rollers positioned on the guide rails on the upper and lower sides, respectively.

However, such a conventional folding door structure has a structure in which a moving guide roller installed to guide opening and closing of the folding door and a hinge hinge for hinging movement of neighboring individual doors are provided separately from each other, There is a problem.

In addition, the moving guide roller and the hinge hinge are separately formed. When the folding door is opened and closed, the door is shaken due to the separate movement. In severe cases, the door is also sent for warping of the door.

In addition, most of folding doors currently installed in Korea are imported and assembled from foreign countries, so that the unit price is considerably high. Also, the construction time is long, and the guide rail formed on the lower side There is a problem that foreign substances are interfered with the opening / closing operation of the entire folding door.

In particular, in case of products imported from foreign countries, it is extremely difficult to repair or repair damage or damage during use. In the case of the hinge hinge for the hinge pivot motion of each individual door, it is integrated with the outer frame forming the individual door and the doorway And it is considerably inconvenient to separate them at the time of maintenance.

As a prior art for solving the above problems, a folding door structure includes an upper frame having an upper guide rail hole formed on an inner bottom surface thereof, An outer frame having a lower frame formed with guide rail holes and left and right side frames vertically connecting the upper and lower frames; A plurality of intermediate hinge hinges hinged together on opposite sides of the respective doors and the neighboring individual doors so that the individual doors adjacent to the individual doors are hingedly pivoted to be folded out of the outer frame; A hinge part hinged to an upper side of the other side of the other door to which the intermediate hinge hinge is not coupled, a roller part having a plurality of vertical rollers fitted in the upper guide rail hole and slidably moving along the upper guide rail hole, An upper guide roller hinge provided on the upper portion and having a support column on which the hinge portion is provided; A hinge part hinged to the lower side of the other side of the individual door to which the intermediate hinge hinge is not coupled, a roller part having a plurality of horizontal rollers fitted in the lower guide rail hole and slidably moving along the lower guide rail hole, And a lower guide roller hinge provided at a lower portion thereof and having a support column on which the hinge portion is provided; The plurality of individual doors are slidably engaged with the upper guide rail holes by roller portions of the upper guide roller hinge, and are slid to be folded at one side of the outer frame.

The prior art configured as above can not selectively open the folding door, and there is a problem that all the folding doors must be opened in order to open the folding door located at the portion to be opened.

Further, since the folding door that is folded is constructed such that the folding door is folded by the hinge, when the folding door is opened, the load of the folding door is increased so that the folding door can not be worn or the folding door can not be weighted. There is a problem that it is broken.

Patent Document: Registered Practical Utility Model No. 20-0439746 (2008.04.30 Announcement)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a folding door structure capable of selectively opening and folding a folding door so that only a folding door installed at a position to be opened or closed can be opened.

Another object of the present invention is to provide a folding door structure which can be easily opened while supporting the weight of the folding door when the folding door is opened.

It is another object of the present invention to provide a folding door structure capable of keeping airtightness between a folding door and a folding door so that external cold or wind or dust can be prevented from entering the room.

According to an aspect of the present invention, there is provided a folding door structure including an upper frame, a lower frame, and a side frame and coupled with a first roller, a second roller, and a third roller to facilitate rotation and movement. A door frame which is in close contact with another adjacent folding door to maintain airtightness; A first roller unit coupled to the door frame for easy rotation and movement of the folding door so as to be movable and rotatable in the rail; A second roller unit installed on the door frame and coupled to the rail to facilitate movement of the folding door; And a third roller unit coupled to the door frame to be able to rotate and move the folding door, and to be movable and rotatable in the rail.

A door frame of the present invention includes an upper frame having an upper front frame and an upper rear frame and having a first roller portion and a second roller portion coupled to each other; A lower frame which is composed of a lower front frame and a lower rear frame and engages with the third roller part; And a side frame provided on the side of the upper frame and the side of the lower frame, respectively, to which the packing is installed to maintain airtightness with the adjacent folding doors.

The side frame of the present invention has a first fitting protrusion formed with a first fitting groove and a second fitting protrusion formed with a second fitting groove formed at a side of the side frame. The second fitting groove is formed obliquely around the first fitting groove, And the packing is installed to prevent the inflow of wind, dust, and foreign matter by keeping the airtightness with the folding door in close contact with the adjacent folding door.

The packing of the present invention is integrally formed of a first packing and a second packing formed with a first engaging groove and a second engaging groove so as to be engageable with the first fitting groove and the second fitting groove, And the second packing is formed to be inclined at an angle around the first packing.

The first roller part of the present invention constitutes a first coupling bar which is inserted into the upper seating groove formed in the upper frame in a sliding manner and fixed by bolts, and a first coupling rod is formed in a vertical direction on one side of the first coupling bar A supporting bar is provided on the first connecting rod so as to support the weight of the folding door when the folding door rotates and is supported by a rail provided on the building wall body, A first roller is rotatably provided on the rod in a rotatable manner and the first bolt is coupled to the first coupling rod through the first roller so that the first roller can be maintained in a state of being coupled to the first coupling rod .

The second roller part of the present invention constitutes a second coupling bar which is fitted in the upper seating groove formed in the upper frame in a sliding manner and fixed by bolts and a second coupling rod is formed in the upper part of the upper part of the second coupling bar in the vertical direction A support bar is provided on the second coupling rod so as to support the weight of the folding door when the folding door rotates and is supported by a rail provided on the building wall body, And a second bolt is coupled to the second coupling rod through the second roller so that the second roller can be maintained in a state of being coupled to the second coupling rod. do.

The third roller part of the present invention constitutes a support coupling bar which is positioned in the lower seating groove of the lower frame and is fixed by the bolt, a third coupling rod is formed in the lower part of the lower part of the support coupling bar, A lower supporting bar serving as a stopper is coupled to the third connecting rod so as not to move in a state in which it is in close contact with one side of another adjacent folding door while being guided in moving along a rail provided on the floor, And a guide support bar coupled to the lower support bar so as to be coupled to the lower support bar so as to facilitate movement and rotation of the folding door, As shown in Fig.

In the present invention, when a part of a folding door is opened, conventionally, all the folding doors are opened to open. However, since the present invention can be opened individually, it is possible to eliminate the troubles of opening all the folding doors There is an effect that can be.

Further, since the first roller portion, the second roller portion, and the third roller portion provided on the upper portion and the lower portion of the folding door respectively allow easy movement in the rails and rotate well, the folding door can be easily opened .

1 is an exploded perspective view showing a folding door structure according to the present invention;
Fig. 2 is a block diagram showing the folding door of Fig. 1; Fig.
Fig. 3 is a block diagram showing the structure of the upper frame of Fig. 1; Fig.
Fig. 4 is a block diagram showing the structure of the lower frame of Fig. 1; Fig.
Fig. 5 is a block diagram showing the structure of the side frame of Fig. 1. Fig.
6 is a configuration diagram showing the configuration of the first roller portion in Fig.
7 is a configuration diagram showing the configuration of the second roller portion in Fig.
8 is a configuration diagram showing the configuration of the third roller portion in Fig.
9 is a sectional view showing a state in which the second roller is engaged with the rail.
10 is a view showing a state in which the folding door of the present invention is installed on a moving guide rail;
11 is a configuration view showing a folding door according to the present invention in a folded state;

Hereinafter, a folding door structure according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view showing a folding door structure according to the present invention, FIG. 2 is a view illustrating a folding state of the folding door of FIG. 1, FIG. 3 is a structural view of the upper frame of FIG. 1, Fig. 5 is a configuration diagram showing the structure of the side frame of Fig. 1, Fig. 6 is a configuration diagram showing the configuration of the first roller portion of Fig. 1, and Fig. 7 Fig. 8 is a configuration diagram showing the configuration of the third roller portion in Fig. 1, Fig. 9 is a sectional view showing a state in which the second roller portion is coupled to the rail, 10 is a view showing a state in which the folding door of the present invention is installed on a moving guide rail, and FIG. 11 is a view showing a folding door according to the present invention in a folded state.

Referring to FIGS. 1 to 11, the present invention includes a door frame 100, a first roller unit 200, a second roller unit 300, and a third roller unit 400.

The door frame 100 includes an upper frame 110, a lower frame 120, a side frame 130, and a packing 140.

The upper frame 110 includes an upper front frame 111 and an upper rear frame 112.

The upper front frame 111 is formed in an 'E' shape, and an upper joining recess 111-1 is formed on an upper side. An upper front supporting protrusion 111-2 supporting an upper front of the glass, .

The upper rear frame 112 has an overall shape of 'C', and an upper coupling protrusion 112-1 is formed on the upper side to correspond to the upper coupling groove 111-1. An upper coupling protrusion 112- 1 is formed on the upper side of the upper roller unit 200 and the upper roller unit 200 is coupled with the upper roller unit 200 and the upper roller unit 200 is coupled to the upper roller unit 200. In addition, A protrusion 112-3 is formed and an upper step (not shown) in which the upper end of the glass is closely contacted is formed on one side where the upper rear support protrusion 112-3 is formed.

The lower frame 120 includes a lower front frame 121 and a lower rear frame 122.

The lower front frame 121 is formed in an 'E' shape like the upper front frame 111, and the lower rear frame 122 is coupled to one side. And a lower front supporting protrusion 121-2 for supporting a lower side of the glass is formed on the upper side.

The lower rear frame 122 is formed in an 'h' shape so that a lower front frame 121 is coupled to one side and a lower front frame 121 is coupled to a lower coupling groove 121-1 A lower seating groove 112-2 in which the third roller portion 200 is engaged is formed at one side where the lower coupling projection 112-1 is formed, The lower rear supporting protrusions 122-3 are formed on the upper portion of the lower rear supporting protrusion so as to support one side of the glass, and a lower step (not shown) in which the lower end of the glass is closely attached is formed on one side of the lower rear supporting protrusion.

The side frames 130 are formed in a '⊃' shape so as to protrude from one side of the upper side.

A first fitting protrusion 131 having a first fitting groove 131-1 and a second fitting protrusion 132 having a second fitting groove 132-1 are formed on the side surface of the side frame 130 And the second fitting recess 132-1 of the second fitting protrusion 132 is formed to be inclined by about 45 degrees with respect to the side face of the side frame 130. [ When the side frames 130 are installed on the side surfaces of the upper frame 110 and the lower frame 120, the side frames 130 are provided so as to correspond to each other so that the side frames 130 can be closely attached to the side surfaces of the adjacent folding doors, .

When the folding door is in close contact with another folding door, a packing 140 is installed in the side frame 130 to maintain airtightness between the folding door and the folding door to prevent wind, dust, etc. from entering the room.

The packing 140 may include a first packing 141 and a second packing 142 at an angle equal to an angle formed by the first fitting groove 131-1 and the second fitting groove 132-1, The first packing 141 and the second packing 142 are connected to each other so that the first packing 141 has a first coupling groove 141- 1 and a second coupling groove 142-1 is formed in the second packing 142 at one side to be coupled to the second fitting protrusion 132. [

The first roller unit 200 constitutes a first coupling bar 210 which is inserted into the upper seating groove 112-1 formed in the upper frame 110 in a sliding manner and fixed by bolts, A first coupling bar 220 is formed in a vertical direction on one side of the bar 210 and a first supporting bar 220 is attached to the first coupling bar 220 to support the weight of the folding door when the folding door rotates. A first roller 240 is installed on the first coupling rod 220 so as to be rotatable inside the rail 500 installed on the building wall body, The first roller 240 is coupled to the first coupling rod 220 through a first roller 240 so that the first roller 240 can be coupled to the first coupling rod 220. [ (250).

The second roller unit 300 constitutes a second coupling bar 310 which is inserted into the upper seating groove 112-2 formed in the upper frame 110 in a sliding manner and fixed by bolts, A second coupling bar 320 is formed at one side of the upper portion of the bar 310 and a second supporting bar 320 is attached to the second coupling bar 320 to support the weight of the folding door when the folding door rotates. And a second roller 340 is mounted on the second coupling rod 320 so as to be rotatable inside the rail 500 installed on the building wall body And the second roller 340 is coupled to the second coupling rod 320 through the second roller 340 so that the second roller 340 can be coupled to the second coupling rod 320. [ (Not shown).

The third roller part 500 is installed on the lower side of the folding door so that it can be easily moved while being supported by the rail 500 when the folding door rotates and moves.

The third roller part 500 constitutes a supporting bar 410 which is positioned in the lower receiving groove 122-2 of the lower frame 120 and fixed by bolts, A third connecting rod 420 is formed at one side of the folding door 420. The folding door serves as a guide when moving along the rail 500 installed on the floor of the building, The lower jig 430 serving as a stopper is coupled to the third jig 420 so that the folding jig 430 is coupled with the lower jig 430 to facilitate movement and rotation of the folding door, And the guide support bar 440 is supported on the inner side of the rail 500.

The lower jig 430 has a rectangular shape and forms a protrusion 431 on one side of a quadrangular shape and a position groove 432 on a side of a quadrangle corresponding to the protrusion 431.

The projecting portion 431 formed on the lower support bar 430 is coupled to the positioning groove 432 of the adjacent lower supporting bar 431 and the other positioning groove 432 is formed in the positioning groove 432 formed corresponding to the projecting portion 431, The protruding portion 431 of the lever 430 is positioned so that the folding door can be moved in a connected state when the folding door is in the open state and when it is brought into close contact with one side.

The guide support bar 440 includes a support plate 441 supported on the inner side of the rail 500 to support and balance the weight of the folding door while the lower support bar 430 supports the third engagement rod 420, A fastening protrusion 442 formed on the upper surface of the support plate 441 to be fixed to the third coupling rod 420 so as to be coupled to the lower surface of the support plate 441 so as to be supported inside the rail 500, And a guide projection 443 formed thereon.

The operation of the folding door structure according to the present invention constructed as above will be described.

A door 500 is installed at an upper portion of the door window frame to allow the folding door to move. The rail 500 is provided with a door 500, The opening 510 is formed and the reinforcing member 520 is installed on the rail 500 at the portion where the opening 510 is formed to prevent the cut surface from being exposed to the outside and to make the appearance of the rail 500 beautiful.

A folding door is constructed so that the rail 500 can be installed and moved or rotated.

The folding door is constructed such that an upper joining recess 111-1 formed in an upper front frame 111 is coupled to an upper joining recess 112-1 formed in an upper rear frame 112, ).

The lower frame 120 is also coupled to the lower coupling protrusion 122-1 formed in the lower rear frame 122 by the lower coupling groove 121-1 formed in the lower front frame 121, do.

The side frames 130 are positioned on the side surfaces of the upper frame 110 and the lower frame 120 with the upper frame 110 and the lower frame 120 being spaced apart from each other.

When the side frame 130 is fixed to one side of the upper frame 110 and the lower frame 120, the first fitting groove 131-1 and the second fitting groove 132-1 Is fixed so as to be directed to the outward direction.

The first fitting protrusion 141 formed on the first packing 141 formed on the packing 140 is inserted into the first fitting protrusion 131, And the second fitting groove 142-1 formed in the second packing 142 is coupled to the second fitting protrusion 142 so that the packing 140 and the other packing 140 can be fixed to each other, Ensure that air, dust, and foreign matter do not enter the room.

The first roller portion 200 is inserted into the upper seating groove 112-2 of the upper frame 110 while the folding door is formed by coupling the upper frame 110, the lower frame 120, The first joining bar 210 of the first joining member 210 is positioned by using a bolt or a screw.

The first support bar 230 and the first roller 240 may be fixed to the first coupling bar 220 formed on the first coupling bar 210 when the first roller 200 is fixed to the upper frame 110. [ The first bolt 250 is fixed to the upper frame 110,

The second roller unit 300 is disposed on the other side of the upper frame 110 in a state where the first roller 200 is installed on the upper frame 110, Install it.

When the folding door is installed on the rail 500 and the supporting bar 410 is positioned in the lower receiving groove 122-2 of the lower frame 110 so as to support the folding door when the folding door is installed on the rail 500, And the third roller unit 400 is installed by fixing using a bolt or a screw.

The lower frame 120 and the guide bar 440 are coupled to the third coupling rod 420 when the third roller unit 400 is fixed to the lower frame 120.

The guide supporting bar 440 coupled to the third connecting rod 420 is generally fastened using a member for connecting the member such as a normal bolt (not shown) or interference fit or welding.

The rails 500 installed on the building wall after the first roller unit 200, the second roller unit 300 and the third roller unit 400 are installed on the upper frame 110 and the lower frame 120, To the folding door.

When the folding door is coupled to the rail 500, the first roller unit 200 and the second roller unit 300 are coupled to the rails 500 installed on the ceiling of the building, And installed on a rail 500 installed on the floor.

When the folding door is moved along the rail 500 in a state where the first roller unit 200, the second roller unit 300 and the third roller unit 400 of the folding door are coupled to the rail 500, The first roller 240 and the second roller 340 installed inside the guide rails 500 move while rotating and the guide support bar 440 slides and moves inside the rails.

In order to rotate the folding door so that the indoor and the outdoor are connected to each other, the second roller unit 300 is drawn out through the opening 510 formed in the rail 500, and the second roller unit 300 is drawn out The folding door rotates about the first roller unit 200 and the third roller unit 400. [

When the folding door rotates, the first support bar 230 of the first roller unit 200 is supported by a guide rail (not shown) formed inside the rail 500, The support plate 441 of the guide support bar 440 is prevented from being inclined from the inside of the rail to the inside of the rail 500, Supporting the weight of the folding door.

The guide protrusion 443 formed at the lower portion of the guide support bar 440 is supported inside the rail 500 so that the folding door can be balanced with the lower support bar 430.

Since the folding door can be pushed to one side of the window frame by being pushed to one side of the window frame in a state where the folding door is opened, a wider opening can be achieved and the folding door can be moved to one side.

In addition, since the folding door can be opened individually by pulling out the second roller part 300 of the folding door through the opening 510 formed in the rail 500, There is an advantage that it is possible to improve the problem of moving both the folding doors to open.

The folding door of the present invention is not limited to a place where the inside and the outside are connected such as the front of the cafe, the front of the restaurant, the store where the terrace is formed, the clothes store, etc., And the living room can be used as a single space.

As described above, the present invention improves the problems of existing folding doors and includes features of existing folding doors, which is advantageous compared with the conventional folding doors.

100: door frame 110: upper frame
111: upper front frame 111-1: upper joining groove
111-2: upper front support projection 112: upper rear frame
112-1: upper engaging projection 112-2: upper seating groove
112-3: upper rear support protrusion 120: lower frame
121: lower front frame 121-1: lower coupling groove
121-2: Lower front supporting protrusion 122-1: Lower coupling protrusion
122-2: Lower seating groove 122-3: Lower rear supporting projection
122: lower rear frame 130: side frame
131: first fitting projection 131-1: first fitting groove
132: second fitting projection 132-1: second fitting groove
140: packing 141: first packing
141-1: first coupling groove 142: second packing
142-1: second coupling groove 200: first roller portion
210: first coupling bar 220: first coupling rod
230: first support bar 240: first roller
250: first bolt 300: second roller portion
310: second coupling bar 320: second coupling rod
330: second support bar 340: second roller
350: second bolt 400: third roller portion
410: Supporting coupling bar 420: Third coupling rod
430: Lower chuck lever 431:
432: Position groove 440: Guide support bar
500: rail 510: opening
520: reinforcing member

Claims

In the folding door structure,
The first roller unit 200 and the second roller unit 300 and the third roller unit 400 are coupled to each other by the upper frame 110, the lower frame 120 and the side frame 130, A door frame 100 which is made to be easy to be held in close contact with another adjacent folding door to maintain airtightness;
A first roller unit 200 coupled to the door frame 100 for easy rotation and movement of the folding door so as to be movable and rotatable in the rail 500;
A second roller portion 300 installed on the door frame 100 to be coupled to the rail to facilitate movement of the folding door; And
And a third roller part (400) coupled to the door frame (100) so as to facilitate rotation and movement of the folding door so as to be movable and rotatable in the rail (500)
The first roller part (200)
The first coupling bar 210 is slidably fitted into the upper seating groove 112-2 formed in the upper frame 110 and fixed by bolts,
A first coupling rod 220 is formed on one side of the first coupling bar 210 in a vertical direction,
A first support bar (230) is supported on the rail from the inside in the first coupling rod (220) so as to support the weight when the folding door rotates,
The first roller 240 is rotatably coupled to the first coupling rod 220 so as to be rotatable inside the rail 500 installed on the building wall,
The first bolt 250 is coupled to the first coupling rod 220 through the first roller 240 so that the first roller 240 can be coupled to the first coupling rod 220 Folding door structure.

The method according to claim 1,
The door frame (100)
An upper frame 110 including an upper front frame 111 and an upper rear frame 112 and coupled with the first roller unit 200 and the second roller unit 300;
A lower frame 120 composed of a lower front frame 121 and a lower rear frame 122 and coupled with the third roller part 400;
A side frame 130 installed at the side of the upper frame 110 and the lower frame 120 to provide a packing 140 for maintaining airtightness with adjacent folding doors;
The folding door structure comprising:

3. The method according to claim 1 or 2,
The side frame (130)
A first fitting protrusion 131 formed with a first fitting groove 131-1 and a second fitting protrusion 132 formed with a second fitting groove 132-1 are formed on a side end,
The second fitting groove 132-1 is formed to have a tilting angle of about 45 degrees with respect to the side surface of the side frame 130 so that the second fitting groove can be in close contact with the side surface of the adjacent folding door. Door structure.

3. The method of claim 2,
The packing (140)
The first packing 141 and the second packing 141 are formed so as to be able to correspond to the first coupling groove 141-1 of the first fitting projection 131 and the second coupling groove 142-1 of the second fitting projection 132, 2 packing 142,
The first packing 141 and the second packing 142 are formed so that the first coupling protrusion 131 of the first fitting protrusion 131 and the second coupling protrusion 142 of the second fitting protrusion 132 of the first fitting protrusion 131, 1) and is mounted on the side frame (130).

delete

The method according to claim 1,
The second roller unit 300 includes:
A second coupling bar 310 which is fitted in the upper seating groove 112-2 formed in the upper frame 110 in a sliding manner and fixed by bolts is formed,
A second coupling rod 320 is formed at one side of the upper portion of the second coupling bar 310 in the vertical direction,
A second support bar 330 is installed on the second coupling rod 320 so as to support the weight when the folding door rotates and is supported inside the rail,
A second roller 340 is rotatably coupled to the second engaging rod 320 so as to be rotatable inside the rail,
Wherein the second bolt (350) is coupled to the second coupling rod (320) so that the second roller (340) can remain coupled to the second coupling rod (320).

The method according to claim 1,
The third roller unit 400 includes:
A support coupling bar 410 which is positioned in the lower seating groove 122-2 of the lower frame 120 and fixed by a bolt,
A third connecting rod 420 is formed at a lower side of the supporting bar 410 in a vertical direction,
The lower jig 430 serves as a guide when moving along the rail 500 and is prevented from moving in a state of being closely attached to one side of the adjacent folding door,
And a guide support bar 440 coupled to the third joining bar 420 is coupled to the lower jig 430 to facilitate movement and rotation of the folding door. Door structure.