Interlocking joint implementing rolling contact and foldable scaffold device comprising same

Abstract

An interlocking joint according to an embodiment of the present invention is an interlocking joint implementing rolling contact and comprises: a first joint member having a first curved surface; and a second joint member having a second curved surface which corresponds to the first curved surface so as to be in rolling contact with the first curved surface, the second joint member being connected to the first joint member so as to rotate axially. In another aspect, a scaffold device according to an embodiment of the present invention comprises: a frame formed in a rectangular parallelepiped shape and formed to be foldable inward from respective side surfaces thereof; support parts formed in a trapezoidal shape, disposed on the front surface and the rear surface of the frame, respectively, and rotatably coupled to the top, bottom, and respective sides of the frame, respectively; and the interlocking joint according to claim 1 for connecting the support parts to be interlocked with each other, wherein as the frame is folded inward from the respective side surfaces thereof, the support parts rotate to the inside of the frame.

Description

Interlocking joint implementing rolling contact, and a foldable scaffolding device including the same

[0001] The present invention relates to an interlocking joint implementing a rolling contact, and a foldable scaffolding device including the same.

[0002] Scaffolding is a device that supports loads such as workers, workpieces, or work tools. When a work area is located at a certain height or higher from the ground, a worker can use scaffolding to access the work area and perform work.

[0003] Scaffolding devices can be utilized in various industrial fields. For example, scaffolding devices can be used for work on objects that are high above the ground, such as buildings, automobiles, ships, and structures.

[0004] The scaffolding device may include a support frame that supports objects such as workers, workpieces, or work tools at a position spaced apart from the ground, and may include a column frame for supporting the support frame against the ground, etc.

[0005] Meanwhile, scaffolding devices can be manufactured to have a large volume to support heavy loads or cover a wide working area.

[0006] However, when moving and storing the scaffolding device, it is advantageous for the volume of the scaffolding device to be smaller, and therefore research is being conducted on a structure that controls the volume of the scaffolding device.

[0007] In particular, it is necessary to develop inter-frame connecting joints that allow each frame to fold in conjunction during compression of the foldable scaffolding device, thereby minimizing the overall volume of the structure.

[0008] On the other hand, working at heights is inevitable during shipbuilding, and as ships become larger, the workload at heights also increases. For this purpose, prefabricated aerial work platforms have been primarily used. However, this makes assembly and disassembly difficult and delays work times within the confined space of a ship. Therefore, a work platform that can be easily installed when needed and conveniently stored when not in use is required.

[0009] As a related document, Korean Patent Publication No. 10-2024-0137965 discloses a scaffolding device capable of transitioning between a folded and unfolded state by partially folding or unfolding the frame structure. However, the scaffolding device has a drawback in that when implementing the folded state, the support parts supporting the frame fold so that they protrude outward. This not only poses a risk of accidents due to the support parts protruding on both sides, but also increases the storage volume.

[0010] The purpose of the present invention is to provide a ladder device that can be easily folded and unfolded.

[0011] Another object of the present invention is to provide a ladder device that can be compactly folded and stored.

[0012] In addition, the present invention provides a round structure that implements rolling contact so that the volume of the entire structure can be minimized by interlocking and folding each frame when the folding scaffolding device is compressed, and the round structures are assembled to contact each other so that the load is transmitted as a whole according to the movement while continuously in contact during the control process of the frame, thereby stably distributing the load concentrated on the joint, and an interlocking joint that implements rolling contact so that the entire scaffolding device can be controlled through multi-axis movement even when the movement of any one member or any one axis is controlled when applied to the folding scaffolding device.

[0013] A linkage joint according to an embodiment of the present invention is a linkage joint that implements rolling contact, comprising: a first joint member having a first curved surface formed thereon; and a second joint member having a second curved surface formed thereon corresponding to the first curved surface so as to be in rolling contact with the first curved surface, and connected to the first joint member so as to be axially rotated.

[0014] Additionally, a connecting member connecting the first joint member and the second joint member may be further included.

[0015] Additionally, the above connecting member can be manufactured from a flexible material or a metal material.

[0016] In addition, the first joint member may include a first bracket body portion; and a first bracket including first bracket wing portions each standing up from both sides of the first bracket body portion and having a first curved surface formed at each corner portion; and a first cover assembled between the first bracket wing portions; and the second joint member may include a second bracket body portion; and a second bracket including second bracket wing portions each standing up from both sides of the second bracket body portion and having a second curved surface formed at each corner portion; and a second cover assembled between the second bracket wing portions.

[0017] In addition, each of the first curved surface and the second curved surface has a step structure between the outer surface and the inner surface, and the step structure between the first curved surface and the second curved surface is formed complementarily so that the first curved surface and the second curved surface can be in rolling contact with each other in an interlocked form.

[0018] In addition, the first bracket body part may include a first cover coupling groove part formed on both sides of the upper surface; a first cover coupling hole part formed on the rear surface opposite to the first curved surface; and a first flange part for connection to a folding ladder frame on at least one of the lower surface and the side surface.

[0019] In addition, the first cover may include a first cover body portion that is bolt-fastened to the first cover coupling hole portion; first protrusions that protrude from both sides of the front of the first cover body portion and have their lower portions inserted into the first cover coupling groove portion; and the first receiving portion formed between the first protrusions.

[0020] In addition, the first bracket wing portion may include a first outer wing portion; and a first inner wing portion that is positioned between the first bracket body portion and the first outer wing portion and is formed relatively lower than the first outer wing portion to form a step with the first outer wing portion.

[0021] In addition, the second bracket body part may include a second cover coupling groove part formed in the center of the upper surface; a second cover coupling hole part formed in the rear surface opposite to the second curved surface; and a second flange part for fastening to a foldable ladder frame on at least one of the lower surface and the side surface.

[0022] In addition, the second cover includes a second cover body portion that is bolt-fastened to the second cover coupling hole portion; and a second protrusion portion that protrudes from the center surface of the second cover body portion and has a lower portion inserted into the second cover coupling groove portion, and both sides of the second protrusion portion can provide a second receiving portion by the second protrusion portion.

[0023] In addition, the second bracket wing portion may include a second outer wing portion; and a second inner wing portion that is positioned between the second bracket body portion and the second outer wing portion and is formed relatively higher than the second outer wing portion to form a step with respect to the second outer wing portion.

[0024] On the other hand, a ladder device according to an embodiment of the present invention comprises a frame formed in a rectangular parallelepiped shape and foldable inwardly on both sides; support members formed in a trapezoidal shape and respectively positioned on the front and rear sides of the frame and rotatably coupled to the upper, lower, and both side portions of the frame; and an interlocking joint according to claim 1 that interlocks the support members to each other, and as the frame is folded inwardly on both sides, the support members rotate inwardly of the frame.

[0025] In addition, the frame includes an upper frame formed in a rectangular shape; a lower frame formed in a rectangular shape; and a connecting frame connecting the upper frame and the lower frame, wherein the connecting frame includes an upper connecting frame having an upper end rotatably coupled to the upper frame; and a lower connecting frame having a lower end rotatably coupled to the lower frame, and the lower end of the upper connecting frame and the upper end of the lower connecting frame can be rotatably coupled to each other.

[0026] In addition, the support part may include a first support part formed in an isosceles trapezoid and rotatably coupled to the upper frame; a second support part formed in an isosceles trapezoid and rotatably coupled to the lower frame; a third support part formed in a right-angled trapezoid and oriented so that the hypotenuse faces the upper frame and rotatably coupled to the upper connecting frame; and a fourth support part formed in a right-angled trapezoid and oriented so that the hypotenuse faces the lower frame and rotatably coupled to the lower connecting frame.

[0027] In addition, the interlocking joint may include a first interlocking joint that rotatably connects the hypotenuses of the first support and the third support; and a second interlocking joint that rotatably connects the hypotenuses of the second support and the fourth support.

[0028] In addition, the upper connecting frame may be allowed to rotate only inwardly of the frame while being oriented vertically downwardly with respect to the upper frame; the lower connecting frame may be allowed to rotate only inwardly of the frame while being oriented vertically upwardly with respect to the lower frame; and the connecting portion of the upper connecting frame and the lower connecting frame may include at least one of the following: being allowed to move only inwardly of the frame while being oriented vertically upwardly with respect to the lower frame.

[0029] Additionally, at least one of the first support, the second support, the third support and the fourth support may be allowed to rotate only inwardly of the frame while being positioned on the front or rear of the frame.

[0030] Additionally, at least one of the first support, the second support, the third support and the fourth support may have a distance between two parallel sides of the trapezoid that is less than half the distance between the front and rear sides of the frame.

[0031] The ladder device according to the present invention is formed in a rectangular hexahedron shape, thereby effectively increasing rigidity, and is formed so as to be foldable inward on both sides, thereby allowing easy and compact folding.

[0032] In this process, the support member rotates and folds inwardly within the frame, allowing the scaffolding device to fold compactly without any horizontal protrusions when fully folded, and allowing each component to be folded parallel from top to bottom. This facilitates easy storage of the scaffolding device, and furthermore, allows multiple scaffolding devices to be stacked and stored.

[0033] According to the interlocking joint implementing rolling contact according to the present invention, when the folding scaffolding device is compressed, each frame is interlocked and folded to form a round structure implementing rolling contact so that the volume of the entire structure can be minimized, and the round structures are assembled to contact each other so that the load is transmitted as a whole according to the movement while continuously in contact during the control process of the frame, thereby stably distributing the load concentrated on the joint, and when applied to the folding scaffolding device, there is an advantage in that the entire control of the scaffolding device is possible through multi-axis movement even if the movement of any one member or any one axis is controlled.

[0034] Figure 1 is a perspective view of a ladder device according to an embodiment of the present invention in an unfolded state.

[0035] Figure 2 is a front view of a ladder device according to an embodiment of the present invention in an unfolded state.

[0036] Figure 3 is a side view of a ladder device according to an embodiment of the present invention in an unfolded state.

[0037] Figure 4 is a plan view of a ladder device according to an embodiment of the present invention in an unfolded state.

[0038] Figure 5 is a perspective view of a ladder device according to an embodiment of the present invention in a folded state.

[0039] Figure 6 is a front view of a ladder device according to an embodiment of the present invention in a folded state.

[0040] Figure 7 is a side view of a ladder device according to an embodiment of the present invention in a folded state.

[0041] Figure 8 is a plan view of a ladder device according to an embodiment of the present invention in a folded state.

[0042] FIG. 9 shows the direction in which each part moves when the ladder device according to an embodiment of the present invention is unfolded and then folded.

[0043] Figure 10 illustrates a hinge whose rotation range can be limited to 90°.

[0044] Figure 11 illustrates a hinge whose rotation range can be limited to 180°.

[0045] Fig. 12 is a perspective view showing a linkage joint that implements rolling contact according to an embodiment of the present invention.

[0046] FIGS. 13 and 14 are exploded perspective views showing a first joint member according to an embodiment of the present invention.

[0047] Figures 15 and 16 are exploded perspective views showing a second joint member according to an embodiment of the present invention.

[0048] Figure 17 is a drawing sequentially showing the axial rotation operation of the linkage joint according to an embodiment of the present invention.

[0049] Fig. 18 is a drawing showing a linkage joint according to an embodiment of the present invention coupled to a folding ladder frame.

[0050] Hereinafter, with reference to the attached drawings, a stepping device and a linkage joint implementing rolling contact according to an embodiment of the present invention will be described in detail.

[0051] Prior to this, the terms or words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, and should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0052] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can be replaced at the time of filing this application.

[0053]

[0054] Scaffolding device

[0055] FIG. 1 is a perspective view of a scaffolding device (100) according to an embodiment of the present invention in an unfolded state. FIG. 2 is a front view of a scaffolding device (100) according to an embodiment of the present invention in an unfolded state. FIG. 3 is a side view of a scaffolding device (100) according to an embodiment of the present invention in an unfolded state. FIG. 4 is a plan view of a scaffolding device (100) according to an embodiment of the present invention in an unfolded state. FIG. 5 is a perspective view of a scaffolding device (100) according to an embodiment of the present invention in a folded state. FIG. 6 is a front view of a scaffolding device (100) according to an embodiment of the present invention in a folded state. FIG. 7 is a side view of a scaffolding device (100) according to an embodiment of the present invention in a folded state. FIG. 8 is a plan view of a scaffolding device (100) according to an embodiment of the present invention in a folded state.

[0056] Referring to FIGS. 1 to 8, a ladder device (100) according to an embodiment of the present invention includes a frame (111, 112, 113), a support (121, 122, 123, 124), and an interlocking joint (131, 132).

[0057] The frame (111-113) may be formed in an approximately rectangular shape. In addition, the frame (111-113) may be formed so as to be foldable inward on both sides.

[0058] More specifically, the frame (111-113) may include an upper frame (111) formed in a roughly rectangular shape, a lower frame (112) formed in a substantially identical rectangular shape to the upper frame (111), and a connecting frame (113) connecting the upper frame (111) and the lower frame (112).

[0059] A plate formed roughly in a rectangular shape may be installed on the upper frame (111). This may serve as a stepping stone for the worker to stand on. However, in the drawing, this stepping stone is omitted to better illustrate the structure of the frames (111-113).

[0060] The connecting frame (113) is provided in four pieces so that the rectangular vertices of the upper frame (111) and the lower frame (112) can be connected respectively.

[0061] A bar may be installed on at least one of the two sides of the frame (111-113) to horizontally connect two adjacent connecting frames (113). This may serve as a ladder for workers to climb up, and may further serve as a reinforcing bar to reinforce the structural rigidity of the frame (111-113).

[0062] The connecting frame (113) may include an upper connecting frame (113A) and a lower connecting frame (113B). The upper end of the upper connecting frame (113A) may be foldably connected to the upper frame (111) via a hinge, for example, as illustrated in FIG. 10, the lower end of the lower connecting frame (113B) may be foldably connected to the lower frame (112) via a hinge, for example, as illustrated in FIG. 10, and the lower end of the upper connecting frame (113A) and the upper end of the lower connecting frame (113B) may be foldably connected to each other via a hinge, for example, as illustrated in FIG. 11.

[0063] Accordingly, the connecting frame (113) is bent so that the lower portion of the upper connecting frame (113A) and the upper portion of the lower connecting frame (113B) move inward, so that the entire frame (111-113) can be folded inward from both sides. For this operation, it is preferable that the upper connecting frame (113A) and the lower connecting frame (113B) have substantially the same length. In the process of the frames (111-113) being folded in this manner, the upper frame (111) and the lower frame (112) can be maintained substantially horizontal.

[0064] The hinge installed at the top of the upper connecting frame (113A) can be formed in such a way that the lower end of the upper connecting frame (113A) can only rotate in a direction approaching the upper frame (111) when the upper connecting frame (113A) is oriented vertically downward with respect to the upper frame (111), and can be restricted so that the lower end of the upper connecting frame (113A) cannot rotate in a direction away from the upper frame (111). The hinge installed at the lower end of the lower connecting frame (113B) can only rotate in a direction approaching the lower frame (112) when the lower connecting frame (113B) is oriented vertically upward with respect to the lower frame (112), and can be restricted so that the upper end of the lower connecting frame (113B) cannot rotate in a direction away from the lower frame (112). A hinge installed between the lower end of the upper connecting frame (113A) and the upper end of the lower connecting frame (113B) can be formed in a manner that allows the connecting portion of the lower end of the upper connecting frame (113A) and the upper end of the lower connecting frame (113B) to move only inward when the upper connecting frame (113A) and the lower connecting frame (113B) are aligned in a straight line, and restricts the connecting portion of the lower end of the upper connecting frame (113A) and the upper end of the lower connecting frame (113B) from moving outward.

[0065] These frames (111-113) can be formed of aluminum material.

[0066] Further explaining the hinge mentioned in the present invention, the hinge may include a flexible material arranged across two adjacent frames, a cover covering the flexible material for each frame, and a rivet securing the frame, the flexible material, and the cover together. Such a hinge may have a rotation range limited to 90° (see FIG. 10) or 180° (see FIG. 11) depending on the shape of the two adjacent covers in contact.

[0067] The support members (121-124) may be formed in a roughly trapezoidal shape. In addition, the support members (121-124) may be respectively positioned on the front and rear sides of the frame (111-113). In addition, the support members (121-124) may be rotatably connected to the upper, lower, and both sides of the frame (111-113).

[0068] More specifically, the support portions (121-124) may include a first support portion (121) formed in an isosceles trapezoid and rotatably coupled to an upper frame (111), a second support portion (122) formed in an isosceles trapezoid and rotatably coupled to a lower frame (112), a third support portion (123) formed in a right-angled trapezoid and rotatably coupled to an upper connecting frame (113A), and a fourth support portion (124) formed in a right-angled trapezoid and rotatably coupled to a lower connecting frame (113B).

[0069] The first support (121) can be oriented so that the longer side of the two parallel sides of the isosceles trapezoid is adjacent and parallel to the upper frame (111). The first support (121) can rotate about an axis parallel to the longer side, for example, through a hinge as illustrated in FIG. 10, between a position where the first support (121) is oriented vertically downward with respect to the upper frame (111) and a position where the first support (121) overlaps parallel to and under the upper frame (111). Here, the hinge can be formed in such a way that the first support (121) can only rotate inwardly of the frames (111-113) when the first support (121) is oriented vertically downwardly with respect to the upper frame (111) and that the first support (121) cannot rotate outwardly of the frames (111-113). The hypotenuse of the isosceles trapezoid of the first support member (121) may form an angle of approximately 45° with respect to the long side. In addition, the distance between two parallel sides of the isosceles trapezoid of the first support member (121) may be less than half the distance between the front and rear sides of the frame (111-113), and it is preferable that it is less than half the distance between the front and rear sides of the frame (111-113).

[0070] The second support member (122) can be oriented so that the longer side of the two parallel sides of the isosceles trapezoid is adjacent and parallel to the lower frame (112). The second support member (122) can rotate about an axis parallel to the longer side, for example, through a hinge as illustrated in FIG. 10, between a position where the second support member (122) is oriented vertically upward with respect to the lower frame (112) and a position where the second support member (122) overlaps the lower frame (112) in parallel. Here, the hinge can be formed in such a way that the second support member (122) can only rotate inwardly of the frames (111-113) when the second support member (122) is oriented vertically upwardly with respect to the lower frame (112), and can restrict the second support member (122) from rotating outwardly of the frames (111-113). The hypotenuse of the isosceles trapezoid of the second support member (122) may form an angle of approximately 45° with respect to the long side. In addition, the distance between two parallel sides of the isosceles trapezoid of the second support member (122) may be less than half the distance between the front and rear sides of the frame (111-113), and it is preferable that it is less than half the distance between the front and rear sides of the frame (111-113).

[0071] The third support member (123) may be formed as a right-angled trapezoid having two parallel sides and a side connecting them at right angles and a side (hypotenuse) connecting them diagonally, such that the hypotenuse faces the upper frame (111) and the longer side of the two parallel sides is adjacent to the upper connecting frame (113A) in parallel. The third support member (123) may be rotatable about an axis parallel to the longer side, for example, through a hinge as illustrated in FIG. 10, between a position where the third support member (123) is arranged on the front or rear of the frame (111-113) and a position where the third support member (123) is arranged on the side of the frame (111-113). Here, the hinge may be formed in such a way that the third support member (123) is allowed to rotate only inwardly of the frame (111-113) when positioned on the front or rear of the frame (111-113) and is restricted from rotating outwardly of the frame (111-113). The hypotenuse of the right trapezoid of the third support member (123) may be approximately 45° to the long side. In addition, the distance between two parallel sides of the right trapezoid of the third support member (123) may be less than half the distance between the front and rear of the frame (111-113), and is preferably less than half the distance between the front and rear of the frame (111-113).

[0072] The fourth support member (124) is formed as a right-angled trapezoid having two parallel sides, a side connecting them at a right angle and a side connecting them diagonally (hypotenuse), so that the hypotenuse faces the lower frame (112) and the longer of the two parallel sides is adjacent to the lower connecting frame (113B). The fourth support member (124) can rotate between a position where the fourth support member (124) is positioned on the front or rear of the frame (111-113) and a position where the fourth support member (124) is positioned on the side of the frame (111-113) around an axis parallel to the longer side through a hinge, for example as shown in FIG. 10. Here, the hinge may be formed in such a way that the fourth support member (124), when positioned on the front or rear of the frame (111-113), allows rotation only inwardly toward the frame (111-113) and restricts rotation outwardly toward the frame (111-113). The hypotenuse of the right-angled trapezoid of the fourth support member (124) may form approximately 45° with respect to the longer side. Additionally, the distance between the two parallel sides of the right-angled trapezoid of the fourth support member (124) may be less than half the distance between the front and rear of the frame (111-113), and it is preferable that it be less than half the distance between the front and rear of the frame (111-113).

[0073] These support members (121-124) can be formed from aluminum material.

[0074] The interlocking joint (131, 132) is a type of hinge and serves to connect the support members (121-124) so ​​that they can be interlocked. In particular, the interlocking joint (131, 132) serves to connect the trapezoidal hypotenuses of two adjacent support members (121-124) so ​​that they can be rotated together.

[0075] More specifically, the linkage joints (131, 132) include a first linkage joint (131) that rotatably connects the hypotenuses of the trapezoids of the first support (121) and the third support (123), and a second linkage joint (132) that rotatably connects the hypotenuses of the trapezoids of the second support (122) and the third support (123).

[0076] The first linkage joint (131) is arranged between the hypotenuse of the trapezoid of the first support (121) and the hypotenuse of the trapezoid of the third support (123), so that they can be rotatably connected to each other around an axis parallel to the corresponding hypotenuses. The first linkage joint (131) can be formed in such a way that, when the first support (121) and the third support (123) are arranged on the front or rear of the frame (111-113), the connection portion between the hypotenuse of the trapezoid of the first support (121) and the hypotenuse of the trapezoid of the third support (123) can only move inward of the frame (111-113), and the connection portion between the hypotenuse of the trapezoid of the first support (121) and the hypotenuse of the trapezoid of the third support (123) can be restricted from moving outward of the frame (111-113).

[0077] The second linkage joint (132) is arranged between the hypotenuse of the trapezoid of the second support (122) and the hypotenuse of the trapezoid of the fourth support (124), so that they can be rotatably connected to each other about an axis parallel to the corresponding hypotenuses. The second linkage joint (132) can be formed in such a way that the connection between the hypotenuse of the trapezoid of the second support (122) and the hypotenuse of the trapezoid of the fourth support (124) can only move inward of the frame (111-113) when the second support (122) and the fourth support (124) are arranged on the front or rear of the frame (111-113), and the connection between the hypotenuse of the trapezoid of the second support (122) and the hypotenuse of the trapezoid of the fourth support (124) can be restricted from moving outward of the frame (111-113).

[0078] The detailed configuration of these linkage joints (131, 132) will be described in more detail later with reference to FIGS. 12 to 18.

[0079] Based on the structure described above, the following describes the folding and unfolding operation of the ladder device (100) according to an embodiment of the present invention.

[0080] FIG. 9 shows the direction in which each part moves when the ladder device (100) according to an embodiment of the present invention is unfolded and then folded.

[0081] First, it is assumed that the ladder device (100) is spread out as shown in FIGS. 1 to 4.

[0082] In this case, the upper connecting frame (113A) and the lower connecting frame (113B) are aligned in a straight line between the upper frame (111) and the lower frame (112), so that the frames (111-113) are developed into a rectangular hexahedron as a whole.

[0083] The support members (121-124) are respectively arranged on the front and rear sides of the frame (111-113).

[0084] In addition, since the third support member (123) and the fourth support member (124) are in contact with each other and support each other, the ladder device (100) can be stably maintained when a load is applied to the inner area of ​​the upper frame (111).

[0085] When the connecting frame (111-113) is bent so that the connecting portion of the upper connecting frame (113A) and the lower connecting frame (113B) moves inward while the ladder device (100) is unfolded (see solid arrows in FIG. 9), the supporting portions (121-124) each rotate inward (see dotted arrows in FIG. 9), and the ladder device (100) is folded as shown in FIGS. 5 to 8.

[0086] When the ladder device (100) is completely folded, the upper frame (111), the first support (121), the third support (123), the upper connecting frame (113A), the lower connecting frame (113B), the fourth support (124), the second support (122), and the lower frame (112) are folded in parallel from top to bottom (see Figs. 6 and 7, etc.), so that it can be folded compactly in the vertical direction.

[0087] In addition, since the support parts (121-124) are all folded by rotating inward, they can be folded compactly without any portion protruding horizontally compared to the upper frame (111) or lower frame (112).

[0088] Therefore, the ladder device (100) can be easily stored, and furthermore, there is an advantage in that a plurality of ladder devices (100) can be stored by stacking them.

[0089]

[0090] Interlocking joints that implement rolling contact

[0091] Below, the detailed configuration of the interlocking joint (131, 132) that can be applied to the ladder device (100) according to an embodiment of the present invention is described.

[0092] Fig. 12 is a perspective view showing a linkage joint that implements rolling contact according to an embodiment of the present invention.

[0093] Referring to FIG. 12, an interlocking joint implementing rolling contact according to an embodiment of the present invention may include at least one of a first joint member (1000), a second joint member (2000), and a connecting member (3000).

[0094] A first curved surface (Ac) having a round structure may be formed on both sides of the first joint member (1000). The first curved surface (Ac) of the first joint member (1000) may be formed at a position corresponding to the second curved surface (Bc) formed on both sides of the second joint member (2000) so as to be in rolling contact with each other.

[0095] Accordingly, the first joint member (1000) and the second joint member (2000) can be assembled so that the first curved surface (Ac) and the second curved surface (Bc), which are round structures, are in contact with each other, and can perform rotational movement (hinge rotational movement) based on the rotational axis (C) connecting the first curved surface (Ac) and the second curved surface (Bc).

[0096] The above first joint member (1000) can be configured to include a first round portion (A1) and a first complementary connecting portion (A2) as its most characteristic elements.

[0097] The above first round portion (A1) may have a first curved surface (Ac) formed on both sides of the first joint member (1000). Here, the first curved surface (Ac) may be formed at a position corresponding to the second curved surface (Bc) so as to be in rolling contact with the second curved surface (Bc) as described above.

[0098] The outer and inner surfaces of the first curved surface (Ac) may be formed to have a stepped structure. Specifically, the outer surface of the first curved surface (Ac) may be relatively higher than the inner surface of the first curved surface (Ac) and may have a stepped structure due to a relatively greater protrusion toward the front (in the direction toward the second curved surface (Bc)). Each stepped structure between the first curved surface (Ac) and the second curved surface (Bc) may be formed complementarily so that the first curved surface (Ac) and the second curved surface (Bc) may be in rolling contact with each other in an interlocked form.

[0099] For example, the outer portion of the first curved surface (Ac) is arranged in a manner such that it contacts the outer portion of the second curved surface (Bc) in the forward direction (in the direction toward the second curved surface (Bc)) and bites a part of the side surface of the inner portion of the second curved surface (Bc) in the inward direction, so that the step structures between the first curved surface (Ac) and the second curved surface (Bc) can be assembled in an interlocked manner.

[0100] The above first complementary joint portion (A2) is formed between the first round portion (A1) of the first joint member (1000) and can be formed at a position corresponding to the second complementary joint portion (B2) of the second joint member (2000) described later.

[0101] Accordingly, the first complementary coupling portion (A2) can come closer to the second complementary coupling portion (B2) or move away from the second complementary coupling portion (B2) when the first joint member (1000) and the second joint member (2000) rotate about the rotation axis (C) (hinge rotational movement). The first complementary coupling portion (A2) can include a first protrusion (1220) and a first receiving portion (1230) described below, and the second complementary coupling portion (B2) can include a second protrusion (2220) and a second receiving portion (2230) described below, and it is preferable that the first complementary coupling portion (A2) and the second complementary coupling portion (B2) have a complementary structure so as to come closer to or move away from each other.

[0102] A second curved surface (Bc) having a round structure may be formed on both sides of the second joint member (2000). The second curved surface (Bc) of the second joint member (2000) may be formed at a position corresponding to the first curved surface (Ac) formed on both sides of the first joint member (1000) so as to be in rolling contact with each other.

[0103] Accordingly, the second joint member (2000) and the first joint member (1000) can be assembled so that the second curved surface (Bc) and the first curved surface (Ac), which are round structures, are in contact with each other, and can rotate (hinge rotation) based on the rotation axis (C) connecting the first curved surface (Ac) and the second curved surface (Bc).

[0104] The above second joint member (2000) can be configured to include a second round portion (B1) and a second complementary joint portion (B2) as its most characteristic elements.

[0105] The second round portion (B1) may be provided with a second curved surface (Bc) formed on both sides of the second joint member (2000). Here, the second curved surface (Bc) may be formed at a position corresponding to the first curved surface (Ac) so as to be in rolling contact with the first curved surface (Ac) as described above.

[0106] The outer and inner surfaces of the second curved surface (Bc) may be formed to have a step structure. Specifically, the inner surface of the second curved surface (Bc) may have a relatively higher height than the outer surface of the second curved surface (Bc) and may have a step structure due to the relatively greater protrusion toward the front (in the direction toward the first curved surface (Ac). Each step structure between the second curved surface (Bc) and the first curved surface (Ac) is formed complementarily so that the second curved surface (Bc) and the first curved surface (Ac) can be in rolling contact with each other in an interlocked form.

[0107] For example, the inner part of the second curved surface (Bc) is arranged in a form in which it contacts the inner part of the first curved surface (Ac) in the forward direction (in the direction toward the first curved surface (Ac)) and is bitten by a part of the side surface of the outer part of the first curved surface (Ac) in the outward direction, so that the step structure between the second curved surface (Bc) and the first curved surface (Ac) can be assembled in a form in which they are interlocked.

[0108] The above second complementary joint portion (B2) is formed between the second round portion (B1) of the second joint member (2000) and can be formed at a position corresponding to the first complementary joint portion (A2) of the first joint member (1000) described later.

[0109] Accordingly, the second complementary joint portion (B2) can come closer to the first complementary joint portion (A2) or move away from the first complementary joint portion (A2) when the first joint member (1000) and the second joint member (2000) rotate (hinge rotation) about the rotation axis (C). And, as described above, it is preferable that the second complementary joint portion (B2) be formed in a complementary structure to the first complementary joint portion (A2).

[0110] The above connecting member (3000) connects the first joint member (1000) and the second joint member (2000), and may include a flexible material with excellent toughness and durability or a metal material, and for example, a strap member may be applied.

[0111] One end of the above connecting member (3000) is inserted and fixed into the central portion of the first joint member (1000), and the other end of the connecting member (3000) is inserted and fixed into the central portion of the second joint member (2000), so that the first joint member (1000) and the second joint member (2000) are opposed to each other and are closely connected.

[0112] The above connecting member (3000) is made of a flexible material or a metal material so that the first joint member (1000) and the second joint member (2000) can freely rotate about an axis.

[0113] Hereinafter, with reference to the attached drawings, the configuration of the first joint member (1000) and the second joint member (2000) will be described in more detail.

[0114] FIG. 13 and FIG. 14 are exploded perspective views showing a first joint member (1000) according to an embodiment of the present invention.

[0115] Referring to FIG. 13, a first joint member (1000) according to an embodiment of the present invention may include at least one of a first bracket (1100) and a first cover (1200).

[0116] The above first bracket (1100) may include at least one of a first bracket body (1110) and a first bracket wing (1120), and may be formed into a roughly '┗┛' structure by the first bracket body (1110) and the first bracket wing (1120).

[0117] The above first bracket body portion (1110) may include at least one of a first cover coupling groove portion (1110a), a first cover coupling hole portion (1110b), and a first flange portion (1110c).

[0118] The first cover coupling groove (1110a) may be formed on both sides of the upper surface of the first bracket body (1110). This first cover coupling groove (1110a) may have a rectangular groove structure, and may be formed in parallel on both sides with the central portion of the upper surface of the first bracket body (1110) interposed therebetween. At this time, the rear side (adjacent to the first cover coupling hole (1110b)) of the first cover coupling groove (1110a) may be open, and the front side (adjacent to the first curved surface (Ac)) may be formed in a closed structure.

[0119] The first cover coupling hole (1110b) may be formed on the rear surface of the first bracket body (1110) in the opposite direction of the first curved surface (Ac). The rear surface of the first bracket body (1110) may be formed as a flat structure having a long length in the horizontal direction, and a plurality of coupling holes for bolt fastening with the first cover (1200) may be formed along the longitudinal direction thereof.

[0120] The first flange portion (1110c) may be formed to protrude from at least one of the lower surface and both side surfaces of the first bracket body portion (1110) for fastening to the foldable ladder frame. A plurality of coupling holes may be formed in the first flange portion (1110c) for fastening with bolts to the foldable ladder frame.

[0121] The first bracket wing portion (1120) may be erected from each of the two sides of the first bracket body portion (1110), and the first curved surface may be formed at each corner portion. Here, the first bracket wing portion (1120) may be erected in a shape that is approximately orthogonal to the first bracket body portion (1110).

[0122] The above first bracket wing portion (1120) may include at least one of a first outer wing portion (1120a) and a first inner wing portion (1120b).

[0123] The above first outer wing portion (1120a) may be formed in a rectangular shape that is long in the horizontal direction and flat, and a first curved surface (Ac) formed in a rounded structure may be formed at a corner portion of one end thereof.

[0124] The first inner wing portion (1120b) is arranged between the first bracket body portion (1110) and the first outer wing portion (1120a), and is formed in a shape that is relatively lower in height than the first outer wing portion (1110a) in the vertical direction and relatively retracted in the front direction than the first outer wing portion (1110a), thereby forming a step with the first outer wing portion (1110a).

[0125] More specifically, the first inner wing portion (1120b) may be formed in a rectangular shape that is long and flat in the horizontal direction, and a first curved surface (Ac) formed in a rounded shape may be formed at a corner portion of one end thereof.

[0126] Accordingly, the first outer wing part (1120a) and the first inner wing part (1120b) may be formed side by side, but may have a larger structure so that the first outer wing part (1120a) protrudes more upwardly and forwardly than the first inner wing part (1120b). In addition, the first outer wing part (1120a) and the first inner wing part (1120b) may each have a first curved surface (Ac) formed at the corner portion on the front side, so that the first curved surface (Ac) of the first outer wing part (1120a) and the first curved surface (Ac) of the first inner wing part (1120b) may have a mutually stepped structure. At this time, the curvatures of the two first curved surfaces (Ac) may be the same.

[0127] As will be described later, the first curved surface (Ac) of the first outer wing portion (1120a) corresponds to the second curved surface (Bc) of the second outer wing portion (2120a) formed in the second joint member (2000), so that the first curved surface (Ac) and the second curved surface (Bc) can be in rolling contact as the first joint member (1000) and the second joint member (2000) rotate (hinge rotate) about the rotation axis (C).

[0128] The first cover (1200) may have a first receiving portion (1230) formed on both sides of the front surface, and may be assembled between the first bracket wing portions (1120). The first receiving portion (1230) may be formed in the same direction as the first curved surface (Ac). The first cover (1200) may include at least one of the first cover body portion (1210), the first protrusion (1220), and the first receiving portion (1230).

[0129] The first cover body part (1210) may be bolt-fastened to the first cover coupling hole part (1110b). More specifically, the first cover body part (1210) may be formed as a flat structure having a long length in the horizontal direction, and may have a shape corresponding to the rear surface of the first bracket body part (1110) in which the first cover coupling hole part (1110b) is formed. In addition, the first cover body part (1210) may have a plurality of coupling holes formed along the longitudinal direction for bolt-fastening with the first cover (1200).

[0130] The above first protrusion (1220) protrudes forward (first curved surface (Ac)) from each of the front sides of the first cover body (1210), and its lower part can be inserted into the first cover coupling groove (1110a) in a sliding manner.

[0131] The front part of the first protrusion (1220) may be formed with an inclined structure, and this structure may correspond to the second receiving portion (2230) formed on both sides of the second cover (2200) described later.

[0132] The first receiving portion (1230) may be formed between the first protrusions (1220). This first receiving portion (1230) may have a structure that is inclined inward, and this inclined structure may correspond to the second protrusion (2220) of the second cover (2200) described below.

[0133] The first joint member (1000) described above is described as an assembly type in which the first bracket (1100) and the first cover (1200) are separable from each other, but it is of course possible to manufacture it as an integral type as well. However, in the case of the assembly type, since one side of the connecting member (3000) is inserted between the first bracket (1100) and the first cover (1200), the connecting member (3000) can be firmly fixed to the first joint member (1000), so the separable type has the advantage of being easier to assemble than the integral type.

[0134] FIG. 15 and FIG. 16 are exploded perspective views showing a second joint member (2000) according to an embodiment of the present invention.

[0135] Referring to FIG. 15, the second joint member (2000) according to an embodiment of the present invention may include at least one of a second bracket (2100) and a second cover (2200).

[0136] The second bracket (2100) may include at least one of a second bracket body (2110) and a second bracket wing (2120), and may be formed into a roughly '┗┛' structure by the second bracket body (2110) and the second bracket wing (2120).

[0137] The second bracket body portion (2110) may include at least one of a second cover coupling groove portion (2110a), a second cover coupling hole portion (2110b), and a second flange portion (2110c).

[0138] The above second cover coupling groove (2110a) can be formed in the center of the upper surface of the second bracket body (2110).

[0139] This second cover coupling groove (2110a) may be formed as a rectangular groove structure, and the rear side (adjacent to the second cover coupling hole (2110b)) of the second cover coupling groove (2110a) may be open, and the front side (adjacent to the second curved surface (Bc)) may be formed as a closed structure.

[0140] The second cover coupling hole (2110b) may be formed on the rear surface of the second bracket body (2110) in the opposite direction of the second curved surface (Bc). Here, the rear surface of the second bracket body (2110) may be formed as a flat structure having a long length in the horizontal direction, and a plurality of coupling holes for bolt fastening with the second cover (2200) may be formed along the longitudinal direction thereof.

[0141] The second flange portion (2110c) may be formed to protrude from at least one of the lower surface and side surface of the second bracket body portion (2110) for fastening to the foldable ladder frame. A plurality of coupling holes may be formed in the second flange portion (2110c) for fastening with bolts to the foldable ladder frame.

[0142] The second bracket wing portion (2120) may be erected from each of the two sides of the second bracket body portion (2110), and a second curved surface (Bc) may be formed at each corner portion. Here, the second bracket wing portion (2120) may be erected in a shape that is approximately orthogonal to the second bracket body portion (2110).

[0143] The second bracket wing portion (2120) may include at least one of a second outer wing portion (2120a) and a second inner wing portion (2120b).

[0144] The above second outer wing portion (2120a) may be formed in a rectangular shape that is long in the horizontal direction and flat, and a second curved surface (Bc) formed in a rounded shape may be formed at a corner portion of one end thereof.

[0145] The second inner wing portion (2120b) is arranged between the second bracket body portion (2110) and the second outer wing portion (2120a), and is formed to be relatively taller than the second outer wing portion (2120a) and relatively retracted forward compared to the second outer wing portion (2120a), thereby forming a step with respect to the second outer wing portion (2120a).

[0146] More specifically, the second inner wing portion (2120b) may be formed in a rectangular shape that is long and flat in the horizontal direction, and a second curved surface (Bc) formed in a rounded shape may be formed at a corner portion of one end thereof.

[0147] Accordingly, the second outer wing part (2120a) and the second inner wing part (2120b) may be formed side by side, but may have a larger structure so that the second inner wing part (2120b) protrudes more upwardly and forwardly than the second outer wing part (2120a). In addition, the second outer wing part (2120a) and the second inner wing part (2120b) may each have a second curved surface (Bc) formed at the corner portion on the front side, so that the second curved surface (Bc) of the second outer wing part (2120a) and the second curved surface (Bc) of the second inner wing part (2120b) may have a mutually stepped structure. At this time, the curvatures of the two second curved surfaces (Bc) may be the same.

[0148] As described above, the second curved surface (Bc) of the second inner wing portion (2120b) corresponds to the first curved surface (ac) of the first inner wing portion (1120a) formed in the first joint member (1000), so that the second curved surface (Bc) and the first curved surface (Ac) can be in rolling contact as the second joint member (2000) and the first joint member (1000) rotate about the rotation axis (C) (hinge rotation operation).

[0149] Meanwhile, the inner surface of the portion of the first outer wing portion (1120a) of the first joint member (1000) that protrudes relatively more than the first inner wing portion (1120b) is in contact with the outer surface of the portion of the second inner wing portion (2120b) of the second joint member (2000) that protrudes relatively more than the second inner wing portion (2210b), and the second joint member (2000) is assembled in a manner of biting the portion in contact from the outside to the inside, thereby serving to fix the first joint member (1000) so that it does not deviate in the direction of the axis (C). Of course, the insertion structure between the first receiving portion (1230) and the second protrusion (2220) can also prevent the first joint member (1000) and the second joint member (2000) from deviating in the direction of the axis (C), thereby increasing the bonding force between them.

[0150] The second cover (2200) may be formed with a second protrusion (2220) and may be assembled between the second bracket wing portions (2120). The second protrusion (2220) is formed in the same direction as the second curved surface (Bc), but is formed at a position corresponding to the first receiving portion (1230) of the first cover (1200), so that it may be inserted into the first receiving portion (1230) or separated from the first receiving portion (1230). The second cover (2200) may include at least one of the second cover body portion (2210), the second protrusion (2220), and the second receiving portion (2230).

[0151] The second cover body part (2210) may be bolt-fastened to the second cover coupling hole part (2110b). More specifically, the second cover body part (2210) may be formed as a flat structure having a long length in the horizontal direction, and may have a shape corresponding to the rear surface of the second bracket body part (2110) in which the second cover coupling hole part (2110b) is formed. In addition, the second cover body part (2210) may have a plurality of coupling holes formed along the longitudinal direction for bolt-fastening with the second cover (2200).

[0152] The second protrusion (2220) protrudes from the central surface of the second cover body (2210), and its lower part can be inserted into the second cover coupling groove (2110a) in a sliding manner.

[0153] The front part of the second protrusion (2220) may have an inclined structure, and this structure may correspond to the first receiving portion (1230) of the first cover (1200) described above.

[0154] The second receiving portion (2230) is a space in which both sides of the second protrusion (2220) are empty, into which the first protrusion (1220) can be inserted. The inner portion of the second receiving portion (2230) may have an inclined structure, and this structure may correspond to the inclined structure of the first protrusion (1220).

[0155] The second joint member (2000) described above is described as an assembly type in which the second bracket (2100) and the second cover (2200) are detachable from each other, but it is of course possible to manufacture it as an integral type as well. However, in the case of the assembly type, since the other side of the connecting member (3000) is inserted between the second bracket (2100) and the second cover (2200), the connecting member (3000) can be firmly fixed to the second joint member (2000), so the detachable type has the advantage of being easier to assemble than the integral type.

[0156] Figure 17 is a drawing sequentially showing the axial rotation operation of the linkage joint according to an embodiment of the present invention.

[0157] As illustrated in FIG. 17, the interlocking joint can perform a rotational motion (hinge rotational motion) between the first joint member (1000) and the second joint member (2000) with respect to the rotational axis (C), and during such rotational motion, rolling contact can be implemented in a state where the rounded surfaces formed on each side of the first joint member (1000) and the second joint member (2000) are interlocked with each other.

[0158] Fig. 18 is a drawing showing a linkage joint according to an embodiment of the present invention coupled to a folding ladder frame.

[0159] As illustrated in FIG. 18, the interlocking joint is installed to connect the two frames (P1, P2) (for example, the hypotenuse of the trapezoid of two adjacent support members (121-124) in the case of the previously described scaffolding device (100)) formed by the first flange portion (1110c) and the second flange portion (2110c) so that each frame can be folded and unfolded through the rotational motion of the hinge.

[0160] According to the present embodiment, when the folding ladder device is compressed, each frame is folded in conjunction with the other to minimize the volume of the entire structure, and a round structure is formed to implement rolling contact, and the round structures on both sides are assembled to contact each other so that the load is transferred as a whole according to the movement while continuously in contact during the control process of the frame, thereby providing an interlocking joint that can stably distribute the load concentrated on the joint.

[0161] In addition, when applied to a folding ladder device, it is possible to provide an interlocking joint that enables overall control of the ladder device through multi-axis movement even when controlling the movement of one member or one axis.

[0162] In the above, it has been described that the interlocking joint implementing rolling contact according to an embodiment of the present invention can be applied to a folding scaffolding device (100) as illustrated in FIGS. 1 to 9, but the interlocking joint implementing rolling contact according to an embodiment of the present invention is not necessarily limited to such use. The interlocking joint implementing rolling contact according to an embodiment of the present invention can be applied to various devices in various fields in addition to the folding scaffolding device (100) as illustrated in FIGS. 1 to 9.

Claims

1. As a linkage joint that implements rolling contact, A first joint member having a first curved surface formed thereon; and A second curved surface corresponding to the first curved surface is formed to be in rolling contact, and a second joint member is included that is connected to the first joint member to be axially rotated. Interlocking joints.

2. In paragraph 1, Further comprising a connecting member connecting the first joint member and the second joint member, Interlocking joints.

3. In paragraph 2, The above connecting member is made of a flexible material or a metal material. Interlocking joints.

4. In paragraph 1, The above first joint member, A first bracket body portion; and a first bracket including a first bracket wing portion that stands up from each side of the first bracket body portion and has a first curved surface formed at each corner portion; and Including a first cover assembled between the first bracket wing parts, The above second joint member, A second bracket body portion; and a second bracket including a second bracket wing portion that stands up from each side of the second bracket body portion and has a second curved surface formed at each corner portion; and Including a second cover assembled between the second bracket wing parts, Interlocking joints.

5. In paragraph 4, Each of the first curved surface and the second curved surface has a step structure between the outer surface and the inner surface, The step structure between the first curved surface and the second curved surface is complementary, so that the first curved surface and the second curved surface are in rolling contact with each other in an interlocked form. Interlocking joints.

6. In paragraph 4, The above first bracket body part, First cover joining grooves formed on both sides of the upper surface; A first cover coupling hole formed on the rear surface opposite to the first curved surface; and Including a first flange portion for fastening to a folding ladder frame on at least one of the lower and side surfaces, Interlocking joints.

7. In paragraph 6, The above first cover, A first cover body part bolted to the first cover coupling hole; A first protrusion protruding from each of the front sides of the first cover body and having a lower portion inserted into the first cover joining groove; and Including the first receiving portion formed between the first protrusions, Interlocking joints.

8. In paragraph 5, The above first bracket wing part, First outer wing; and A first inner wing portion is disposed between the first bracket body portion and the first outer wing portion, and is formed relatively lower than the first outer wing portion to form a step with the first outer wing portion. Interlocking joints.

9. In paragraph 5, The above second bracket body part, A second cover joining groove formed in the center of the upper surface; A second cover coupling hole formed on the back surface opposite to the second curved surface; and Including a second flange portion for fastening to a folding ladder frame on at least one of the lower and side surfaces, Interlocking joints.

10. In paragraph 4, The above second cover, A second cover body part bolted to the second cover coupling hole; and It includes the second protrusion that protrudes from the central surface of the second cover body and has a lower portion inserted into the second cover joining groove, Both sides of the second protrusion provide a second receiving portion by the second protrusion, Interlocking joints.

11. In Article 5, The above second bracket wing part, Second outer wing; and A second inner wing part is disposed between the second bracket body part and the second outer wing part, and is formed relatively higher than the second outer wing part to form a step with the second outer wing part. Interlocking joints.

12. A frame formed in a rectangular shape and foldable inward on both sides; Supporting members formed in a trapezoidal shape and positioned respectively on the front and rear sides of the frame and rotatably connected to the upper, lower and both sides of the frame; and Including an interlocking joint according to claim 1, which connects the above support parts so as to be interlocked with each other, As the frame is folded inward on both sides, the support member rotates inwardly of the frame. Scaffolding device.

13. In paragraph 12, The above frame is, The upper frame is formed in a rectangular shape; a lower frame formed in a rectangular shape; and Includes a connecting frame connecting the upper frame and the lower frame, The above connecting frame is, an upper connecting frame having an upper end rotatably connected to the upper frame; and The lower part includes a lower connecting frame rotatably connected to the lower frame, The lower part of the upper connecting frame and the upper part of the lower connecting frame are rotatably connected to each other. Scaffolding device.

14. In paragraph 13, The above support part, A first support formed in an isosceles trapezoid shape and rotatably connected to the upper frame; A second support formed in an isosceles trapezoid shape and rotatably connected to the lower frame; A third support member formed in a right-angled trapezoid and oriented so that the hypotenuse faces the upper frame and is rotatably connected to the upper connecting frame; and A fourth support member is formed in a right-angled trapezoid shape and is oriented so that the hypotenuse faces the lower frame and is rotatably connected to the lower connecting frame. Scaffolding device.

15. In paragraph 14, The above interlocking joint is, A first linkage joint that rotatably connects the hypotenuse of the first support portion and the third support portion; and Including a second linkage joint that rotatably connects the hypotenuse of the second support portion and the fourth support portion to each other. Scaffolding device.

16. In paragraph 13, The upper connecting frame is allowed to rotate only inwardly of the frame while being oriented vertically downward with respect to the upper frame; The lower connecting frame is allowed to rotate only inwardly of the frame while being oriented vertically upward with respect to the lower frame; The connecting portion of the upper connecting frame and the lower connecting frame includes at least one of the following: allowing the upper connecting frame and the lower connecting frame to move only inwardly of the frame while being aligned in a straight line; Scaffolding device.

17. In paragraph 14, At least one of the first support, the second support, the third support and the fourth support is disposed on the front or rear of the frame and is allowed to rotate only inwardly of the frame. Scaffolding device.

18. In paragraph 14, At least one of the first support, the second support, the third support and the fourth support has a distance between two parallel sides of the trapezoid that is less than half the distance between the front and rear sides of the frame. Scaffolding device.

Images