A flat folding structure

Abstract

The present invention relates to the technical field of fitness equipment, and in particular to a flat folding structure. The flat folding structure comprises a plurality of plates connected by hinges, and a tensioning assembly for tensioning the plates. The front and rear faces of the plates are provided with mortises and tenons, respectively. The tenon of the front plate is inserted into and matched with the tenon of the rear plate. The tensioning assembly comprises a rope and a switch for tensioning the rope. The switch is provided at the frontmost plate, and the rope is used to connect the switch and the rearmost plate. The flat folding structure of the present invention can tension the plates by the switch of the tensioning assembly, so that the connection between the plates is stable during use. When the switch is released, the tenon of the front plate can be separated from the tenon of the rear plate, so that the plates are conveniently folded, stored and transported.

Description

Technical Field

[0001] The invention relates to the technical field of fitness equipment, in particular to a flat folding structure. Background Art

[0002] With the continuous progress of society and the improvement of living standards, the demand for health and the importance of physical exercise have reached an unprecedented level from the country to the ordinary people. In real life, due to factors such as high work pressure and little free time, it is difficult for many people to take out special time to exercise, and going to a professional gym is even more of an unattainable luxury. The current fitness equipment on the market is either too large and too professional, which not only occupies a large indoor space, but is also not suitable for ordinary families and other non-professional fitness personnel; or the function is single and cannot achieve a good exercise effect.

[0003] See also Figure 1 , the Chinese utility model patent with announcement number CN206342859U discloses a multifunctional foldable fitness board, including a main board and an expansion board; the main board is provided with a support block, a tool board, a cup groove, a sundries groove, a foot board, a rotating rod, a hook groove, a hook head, a foot ring, a rotating shaft, a clamping rod, an elastic rope, a ring, a T-shaped elastic rope and a wristband; the main board is divided into two parts, and the two main boards are connected together by a hinge; the expansion board is provided with a slide groove, a hand push board, an anti-slip pad and a pulley; there are two expansion boards, which are respectively connected to the front and rear sides of the left end of the main board by hinges; the main board of the present invention is folded in half and stored; the support block is used to support the main board; the cup groove facilitates the water cup to be stably placed on the tool board, so that the exerciser can drink water; the sundries groove is used to place small items carried by the exerciser; when the exerciser does sit-ups, the foot board is rotated to a vertical position, so that the user can put his feet on the foot board; the rotating rod rotates up and down; the pulley facilitates the sliding of the hand push board. The two main boards of the multifunctional foldable fitness board are connected only by a hinge. Although it is convenient for folding and storage, the connection between the two main boards is unstable during use and cannot be used for movements that require reciprocating sliding between the two main boards. Summary of the invention

[0004] The present invention aims to provide a flat plate folding structure, which has the advantages of stable connection between plates and convenient folding.

[0005] To achieve the above advantages, the flat folding structure provided by the present invention includes a plurality of plate bodies connected by hinges, tensioning plate bodies and tensioning components of the plate bodies, the front end face and the rear end face of the plate body are respectively provided with mortises and tenons, the tenon of the front plate body is inserted into and matched with the mortise of the rear plate body, the tensioning component includes a rope and a switch for tensioning the rope, the switch is arranged at the front end plate body, and the rope is used to connect the switch and the rear end plate body.

[0006] In one embodiment of the present invention, the switch is a cylindrical structure with a straight-line torsion portion on the upper surface, a blind hole is provided on the side of the switch, a spring and a sphere are provided in the blind hole, the frontmost plate is provided with a depression for accommodating part of the sphere, and when the switch is rotated to tighten the rope to tighten the frontmost plate and the rearmost plate, the depression corresponds to the position of the sphere.

[0007] In one embodiment of the present invention, the hinge includes a metal sheet, a pair of connecting seats, and a bolt. The pair of connecting seats are respectively connected and fixed to the front plate body and the rear plate body. The metal sheet is provided with a through groove. The connecting seat has an anti-jump protrusion accommodated in the through groove. The width of the anti-jump protrusion is the same as the width of the middle part of the through groove. The bolt is connected and fixed to the connecting seat, and the bolt is used to press the metal sheet. The through groove has an enlarged portion at both ends, and the enlarged portion allows the anti-jump protrusion to rotate.

[0008] In one embodiment of the present invention, a wire groove for accommodating the rope is formed on the lower surface of the plate body.

[0009] In one embodiment of the present invention, a column is fixed to the rear end of the rope, and a compression spring is provided between the column and the rear end plate.

[0010] In the present invention, the flat folding structure can tighten the plates by using the switch of the tensioning assembly, so that the connection between the plates is stable during use; when the switch is released, the tenon of the front plate can be separated from the mortise of the rear plate, which facilitates the folding, storage and transportation of the plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Shown is a structural schematic diagram of an existing multifunctional folding fitness board.

[0012] Figure 2 Shown is a schematic structural diagram of a multifunctional fitness board according to a first embodiment of the present invention.

[0013] Figure 3 Shown Figure 2 A schematic structural diagram of a flat plate of a multifunctional fitness board.

[0014] Figure 4 Shown Figure 3 A partial enlarged view of F1.

[0015] Figure 5 Shown Figure 3 A partial enlarged view of F2.

[0016] Figure 6 Shown Figure 3 Exploded diagram of the hinge of the multi-function fitness board.

[0017] Figure 7 Shown Figure 3 An exploded diagram of the switch of the multi-function fitness board.

[0018] Figure 8 Shown Figure 3 A schematic diagram of the partial structure of the bottom of the multifunctional fitness board.

[0019] Fig. 9 Shown Figure 3 A top view of a board body of a multifunctional fitness board.

[0020] Fig.10 Shown Fig. 9 A schematic structural diagram of the first elastic rope connecting part, the second elastic rope connecting part, the third elastic rope connecting part and the fourth elastic rope connecting part of the board body of the multifunctional fitness board.

[0021] Fig.11 Shown Figure 3 A schematic diagram of the structure of a skateboard and a flexible pad of a multifunctional fitness board.

[0022] Fig.12 Shown Figure 3 A schematic structural diagram of the front portion of a flat plate of a multifunctional fitness board.

[0023] Fig.13 Shown Fig.12 A partial enlarged view of F3.

[0024] Fig.14 Shown Figure 3 A structural schematic diagram of a skateboard and a flexible pad of a multifunctional fitness board from another perspective.

[0025] Fig.15 Shown Fig.14 Schematic diagram of the horizontal connection state of the skateboard and the elastic rope of the multifunctional fitness board.

[0026] Fig.16 Shown Fig.14 Schematic diagram of the vertical connection state of the skateboard and the elastic rope of the multifunctional fitness board.

[0027] Fig.17 Shown Figure 2 A schematic cross-sectional view of the end of the elastic rope of the multi-functional fitness board.

[0028] Fig.18 The diagram is a schematic structural diagram of a multifunctional fitness board according to a second embodiment of the present invention, in which the board body is divided into three parts.

[0029] Fig.19 The diagram is a schematic structural diagram of a multifunctional fitness board according to a third embodiment of the present invention, in which the board body is composed of five pieces.

[0030] Fig. 20 The figure shows the use state of the multifunctional fitness board of the present application in a vertical position.

[0031] Fig.21 The figure shows the initial state of the multifunctional fitness board of the present application with the skateboard placed horizontally and the pins removed.

[0032] Fig. 22 Shown Fig.21 A schematic diagram of the state of the multifunctional fitness board after the skateboard is placed horizontally and the back of the skateboard is pressed down with the pins removed.

[0033] Fig.23 The figure shows a schematic diagram of a state where the skateboard of the multifunctional fitness board of the present application is placed horizontally and pulled toward the middle by an elastic rope.

[0034] Fig.24 The figure shows a schematic diagram of a state where the skateboard of the multifunctional fitness board of the present application is placed horizontally and pulled toward both ends by elastic ropes.

[0035] Fig.25 Shown is a schematic diagram of a folded state of the multifunctional fitness board of the present application. DETAILED DESCRIPTION

[0036] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation method, structure, characteristics and effects of the present invention in combination with the accompanying drawings and preferred embodiments.

[0037] See also Figure 2 The multifunctional fitness board of this embodiment includes a flat plate 1, a slide plate A, a slide plate B, and an armrest 3. For the convenience of description, the end of the flat plate 1 close to the armrest 3 is called the front end, and the end away from the armrest 3 is called the rear end.

[0038] See also Figure 3-6 The flat plate 1 includes a plurality of plate bodies 12 connected by hinges 11, and a tensioning assembly 13 for tensioning the plate bodies 12. The flat plate 1 is provided with a first slide rail 14 and a second slide rail 15 which are parallel to each other. A wire groove 16 for accommodating a rope 132 of the tensioning assembly 13 is provided on the lower surface of the flat plate 1. The plate bodies 12 are at least two pieces. Preferably, the plate bodies 12 are four pieces.

[0039] See also Figure 4 The front and rear surfaces of the plate body 12 are respectively provided with a mortise 120 and a tenon 121 , and the tenon 121 of the front plate body 12 is inserted and matched with the mortise 120 of the rear plate body 12 .

[0040] See also Figure 6The hinge 11 is located on both sides of the plate body 12, and is used to hinge the plate body 12 with another plate body 12. The hinge 11 includes a metal sheet 112, a pair of connecting seats 113, and a bolt 114. The pair of connecting seats 113 are respectively connected and fixed to the front plate body 12 and the rear plate body 12. The metal sheet 112 is provided with a through groove 112a, and the connecting seat 113 has an anti-jumping protrusion 113a accommodated in the through groove 112a, and the width of the anti-jumping protrusion 113a is the same as the width of the middle part of the through groove 112a. The bolt 114 is connected and fixed to the connecting seat 113, and the bolt 114 is used to press the metal sheet 112, and the two ends of the through groove 112a have an enlarged portion 112b, and the enlarged portion 112b allows the anti-jumping protrusion 113a to rotate.

[0041] See also Figure 5 , Figure 7-8 The tensioning assembly 13 includes a switch 131 disposed at the frontmost plate 12 and a rope 132 for connecting the switch 131 and the rearmost plate 12. A blind hole 131a is provided on the side of the switch 131, and a spring h1 and a ball q1 are provided in the blind hole 131a. The frontmost plate 12 is provided with a recess 123 for accommodating part of the ball q1. When the switch 131 is rotated to make the rope 132 tighten the frontmost plate 12 and the rearmost plate 12, the recess 123 corresponds to the position of the ball q1. The switch 131 is a cylindrical structure with a straight-line torsion portion 131b on the upper surface. A column 132a is fixed at the rear end of the rope 132, and a compression spring h2 is provided between the column 132a and the rearmost plate 12. Specifically, the rear end of the rope 132 is covered with a solenoid 132b, the column 132a is fixed to the rear end of the rope 132, one end of the solenoid 132b abuts against the column 132a, the solenoid 132b is connected to a nut 132c, one end of the compression spring h2 abuts against the nut 132c, and the other end abuts against the rear end plate 12. When the rope 132 tightens the front end plate 12 and the rear end plate 12, the compression spring h2 is compressed to maintain the tension of the rope 132. In other embodiments, the switch 131 can also be set at the rear end plate 12, and the rope 132 is used to connect the switch 131 and the front end plate 12.

[0042] See also Fig. 9 The first guide wheel 21, the first elastic cord connection part 22, the second elastic cord connection part 23, the second guide wheel 24, the third guide wheel 25, the third elastic cord connection part 26, the fourth elastic cord connection part 27, and the fourth guide wheel 28 are respectively arranged next to the first slide rail 14 and the second slide rail 15 from front to back. Preferably, the first slide rail 14 and the second slide rail 15 are respectively a pair of slide grooves. In other embodiments of the present application, the first slide rail 14 and the second slide rail 15 can also be one slide groove or three slide grooves respectively.

[0043] See also Fig.10The first elastic cord connection part 22, the second elastic cord connection part 23, the third elastic cord connection part 26, and the fourth elastic cord connection part 27 have the same structure and include: a recess 200 formed on the flat plate 1, and a through slot 201 located beside the recess 200 for allowing the elastic cord body 71 to pass through. The recess 200 is used to accommodate the enlarged portion 72 of the elastic cord 7.

[0044] See also Figure 8 , Fig.10 A plate fixing recess 17 is provided at the front, middle or rear of the plate 1, and a slide plate A and / or slide plate B is provided with a slide plate fixing recess S1 corresponding to the plate fixing recess 17. The slide plate A or the slide plate B can be axially fixed to the plate 1 in cooperation with a limiting block (not shown) which is partially accommodated in the plate fixing recess 17 and partially accommodated in the slide plate fixing recess S1.

[0045] See also Figure 12-13 The front end of the flat plate 1 is provided with an armrest connection seat 18. The armrest 3 is hinged to the armrest connection seat 18. The armrest connection seat 18 is provided with a plurality of angle adjustment holes 180. The armrest 3 is provided with a connection through hole 30 corresponding to the angle adjustment hole 180. When one of the angle adjustment holes 180 corresponds to the connection through hole 30, the armrest 3 and the armrest connection seat 18 can be fixed with the pin 5. The angle adjustment of the armrest 3 can adapt to different users. The armrest connection seat 18 is rotatably connected to a rotating column 181, and the lower end surface of the armrest 3 has an arc surface 36 that fits the side of the rotating column 181.

[0046] A movable rod 31 extending forward and downward is hinged in the middle of the armrest 3, and a transverse wheel rod 311 is provided at the lower end of the movable rod 31, and rollers 311a are provided at both ends of the transverse wheel rod 311. An elastic connecting rope 312 is provided between the lower end of the movable rod 31 and the armrest 3 or the flat plate 1. A sit-up cross bar 32 is fixed at the lower part of the armrest 3, and a plurality of backrest cross bars 33 are provided in the middle of the armrest 3. An annular gripping portion 34 is provided at the upper end of the armrest 3, and a plurality of hinge points 35 that can be hinged to the movable rod 31 are provided on the armrest 3.

[0047] The handrail 3 can also be formed by a plurality of pipe bodies 300 being connected to each other by sockets. This structure allows the handrail 3 to be adjusted in height as required, and saves packaging and transportation space.

[0048] See also Fig.11 , Fig.14The structures of skateboard A and skateboard B in the present application are the same, and both are mirror-symmetrical when used. The lower surface of skateboard A is provided with a first sliding part S2 and a second sliding part S3 corresponding to the first slide rail 14 and the second slide rail 15, and the edge of the upper surface of skateboard A protrudes upward to accommodate the flexible pad 6, and the flexible pad 6 is detachably connected to skateboard A. When skateboard A does not have the flexible pad 6, it is used to contact the user's feet. When skateboard A is placed with the flexible pad 6, it can contact the user's legs, buttocks, knees, back, hands, and elbows. The protrusion a1 on the edge of skateboard A can form a depression to accommodate the flexible pad 6 or the foot. Four mounting posts 61 are provided on the lower surface of the flexible pad 6, and skateboard A is provided with corresponding blind holes or through holes a2.

[0049] Preferably, the first sliding part S2 and the second sliding part S3 are a pair of universal wheels. In other embodiments of the present application, the first sliding part S2 and the second sliding part S3 can also be sliders.

[0050] When the slide plates A and B are in a horizontal state, the first sliding portion S2 and the second sliding portion S3 of the slide plates A and B respectively slide with the first slide rail 14 and the second slide rail 15. When the slide plates A and B are in a vertical state, the first sliding portion S2 and the second sliding portion S3 of the slide plates A slide with the first slide rail 14, and the first sliding portion S2 and the second sliding portion S3 of the slide plates B slide with the second slide rail 15.

[0051] See also Figure 14-16 The two ends and sides of the skateboard A and skateboard B are respectively provided with a vertical state connection part L1 and a horizontal state connection part L2 for detachable connection with the elastic rope 7. There are three states of connection between the skateboard A and the elastic rope 7: the first state is that the skateboard A is vertically placed, and there are elastic ropes 7 at both ends of the skateboard A, wherein the elastic rope t1 is fixed to the rear end of the skateboard A and then connected and fixed to the third elastic rope connection part 26 from above the flat plate 1 through the fourth guide wheel 28 and from below the flat plate 1, and the elastic rope t2 is fixed to the front end of the skateboard A and then connected and fixed to the second elastic rope connection part 23 from above the flat plate 1 through the first guide wheel 21 and from below the flat plate 1; the second state is that the skateboard A is vertically placed, and there is an elastic rope 7 on one side; the third state is that the skateboard A is horizontally placed, and there is an elastic rope 7 on one side.

[0052] See also Figure 16-17 The elastic cord 7 is used to be detachably connected to the connecting body, and includes an elastic cord body 71 and an enlarged portion 72. The enlarged portion 72 is provided at the end of the elastic cord body 71, and the connecting body is provided with an insertion hole 81 and a clamping hole 82. The insertion hole 81 allows the enlarged portion 72 to pass through, and the clamping hole 82 does not allow the enlarged portion 72 to pass through. There is a through groove 83 between the insertion hole 81 and the clamping hole 82 to allow the elastic cord 7 to pass through. After the enlarged portion 72 passes through the insertion hole 81, the enlarged portion 72 is moved to allow the elastic cord 7 to pass through the through groove 83, and the enlarged portion 72 abuts against the clamping hole 82. A wire groove 84 for accommodating the elastic cord 7 is provided next to the clamping hole 82.

[0053] Furthermore, the elastic cord 7 is a hollow tubular structure. A sphere q2 is plugged at the end of the elastic cord body 71 to form an enlarged portion 72. A heat shrink tube 73 is provided on the outer sleeve of the end of the elastic cord 7, and the heat shrink tube 73 fits with the end of the elastic cord 7. In this embodiment, the skateboard A and the skateboard B serve as connectors connected to the elastic cord 7. Preferably, the elastic cord body 71 is made of rubber. The sphere q2 is made of plastic or metal. The heat shrink tube 73 is sleeved outside the end of the elastic cord body 71 where the sphere q2 is plugged. The heat shrink tube 73 may not fit with the end of the elastic cord 7. In addition, the elastic cord 7 of this structure can also be applied to other connectors, such as a chest expander with an elastic cord 7.

[0054] See also Fig.18 In the second embodiment of the present application, the plate body 12 is composed of three pieces.

[0055] See also Fig.19 In the third embodiment of the present application, the plate body 12 is composed of five pieces.

[0056] See also Figure 20-25 In this application, it should be noted that when the hands, knees, and buttocks are used to contact the skateboard, the flexible pad 6 should be placed on the skateboard, and when the feet are used to contact the skateboard, the flexible pad 6 should be removed. The multifunctional fitness board in this application can be used for the following exercises, but is not limited to this:

[0057] In the vertical mode, both ends of the slide board A and the slide board B are connected with elastic ropes 7, which play a role in resetting. The user can place both hands or feet on the slide board A and the slide board B respectively, and can slide the slide boards A and B back and forth alternately, do cross steps or crawling exercises, and exercise the lower limbs or upper limbs. When doing crawling exercises, the feet can be placed on the ground or on the horizontal bar in the middle of the handrail 3;

[0058] Skateboard A and skateboard B can also be used as yoga mats. For example, in a vertical state, the left foot is placed on skateboard A, and the right hand is placed on skateboard B, with skateboard A at the rear end and skateboard B at the front end, and the right foot and left hand are suspended in the air to control balance.

[0059] In the horizontal mode, skateboard A is placed on a flexible pad 6, and the user can sit on skateboard A and put his feet on skateboard B, so that the distance between skateboards A and B can change. The user can constantly bend his knees and tighten his abdomen to strengthen his abdomen. The elastic rope 7 can pull skateboards A and B toward the center to assist, or pull skateboards A and B toward the ends to increase the intensity of exercise. Skateboard B can also be fixed at the rear end, and the user can sit on skateboard B and slide skateboard A with his feet. Skateboard A can also be fixed at the front end, and the user can sit on skateboard A and slide skateboard B with his feet, so that the user can lean back against the handrail 3;

[0060] The user can remove the pin 5 at the hinge between the armrest 3 and the armrest connecting seat 18, fix the skateboard A and / or skateboard B to the front end of the flat plate 1, sit on the skateboard B with the back against the armrest 3, and use the back to press down on the armrest 3 to exercise the back and abdomen. The elastic connecting rope 312 of the armrest 3 can play a role in assisting. Figure 21-22 ;

[0061] The user can sit on the skateboard B, hook his feet on the sit-up bar 32 at the lower end of the handrail 3, and bend his knees to slide the skateboard B;

[0062] The user can fix the skateboard B axially in the middle of the flat plate 1, hook the feet on the sit-up crossbar 32, and do sit-up exercises;

[0063] The user can fix the slides A and B axially in the middle of the flat plate 1, sit sideways on the slides A and B, lift the legs so that the legs are suspended in the air to do stretching and contraction exercises, and exercise the abdomen;

[0064] The user can also place the ankle on the horizontal bar in the middle of the handrail 3, put the hands on the skateboard A and arch the waist to control the skateboard A to slide forward and backward, or put the feet or knees on the skateboard A, put the hands on the skateboard B and arch the waist to control the skateboard B to slide forward and backward (similar to the ab wheel);

[0065] The user can also remove the flexible pad 6 and place both feet on the skateboard A and skateboard B respectively, so that the distance between skateboard A and skateboard B changes, and the user can do splits continuously to exercise the thighs. The elastic rope 7 contracts inwards to play a boosting role. The elastic rope 7 can also pull the skateboards A and B to both ends to increase the intensity of the exercise. Figure 23-24 .

[0066] The skateboard A can also be fixed to the rear end of the flat plate 1, and the feet can be placed on the skateboard B, so that the distance between the skateboards A and B can be changed. The user can continuously bend the knees and tighten the abdomen, which can play a role in strengthening the abdomen.

[0067] When not in use, the adjacent plate bodies 12 are pulled to disengage the tenon 121 of the front plate body from the mortise of the rear plate body 12. At this time, the anti-jump protrusion 113a enters the enlarged portion 112b and is in a rotatable state. Therefore, the adjacent plate bodies 12 can be folded to achieve the effect of reducing the occupied space.

[0068] The multifunctional fitness board of the present invention has multiple functions such as push-ups, sit-ups, abdominal exercises, knee flexion exercises, back exercises, leg exercises, leg stretching, etc. It has a simple structure, is convenient and practical, and has a wide range of applications. The board is foldable and the armrests are detachable, saving packaging and transportation space.

[0069] In the present application, a spherical body is plugged at the end of the elastic rope main body to form an enlarged portion, and the connecting body is provided with a clamping hole and an insertion hole, and a through groove is provided between the insertion hole and the clamping hole to allow the elastic rope main body to pass through. After the enlarged portion passes through the insertion hole, the enlarged portion is moved to allow the elastic rope main body to pass through the through groove, and the enlarged portion abuts against the clamping hole, thereby facilitating the connection and disassembly between the elastic rope main body and the connecting body, so that the connecting body can be connected to elastic rope main bodies of different specifications (i.e., different elastic forces) to meet the needs of different groups of people for the required exercise.

[0070] In the present application, the flat folding structure can tighten the boards by using the switch of the tensioning assembly, so that the connection between the boards is stable during use and the skateboards A and B are not stuck; when the switch is released, the tenon of the front board can be separated from the mortise of the rear board, making it convenient for the boards to be folded, stored and transported.

[0071] The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A flat folding structure, comprising a plurality of plates connected by hinges, characterized in that: It also includes a tensioning assembly for tensioning the plates, wherein the front and rear faces of the plates are respectively provided with mortises and tenons, the tenons of the front plate are inserted into and matched with the tenons of the rear plate, the tensioning assembly includes a rope and a switch for tensioning the rope, the switch is provided at the frontmost plate, and the rope is used to connect the switch and the rearmost plate; The hinge includes a metal sheet, a pair of connecting seats, and a bolt. The pair of connecting seats are respectively connected and fixed to the front plate and the rear plate. The metal sheet is provided with a through groove. The connecting seat has an anti-jumping protrusion accommodated in the through groove. The width of the anti-jumping protrusion is the same as the width of the middle part of the through groove. The bolt is connected and fixed to the connecting seat, and the bolt is used to press the metal sheet. The two ends of the through groove have enlarged parts, and the enlarged parts allow the anti-jumping protrusion to rotate. A column is fixed to the rear end of the rope, and a compression spring is arranged between the column and the rear end plate.

2. The flat folding structure according to claim 1, characterized in that: The switch is a cylindrical structure with a straight-line torsion portion on the upper surface, a blind hole is opened on the side of the switch, a spring and a ball are arranged in the blind hole, and the frontmost plate is provided with a depression for accommodating part of the ball. When the switch is rotated to tighten the rope to the frontmost plate and the rearmost plate, the depression corresponds to the position of the ball.

3. The flat folding structure according to claim 1, characterized in that: A wire groove for accommodating the rope is provided on the lower surface of the plate body.

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