Movable retractable precast beam up-and-down safety channel device

Abstract

The utility model discloses a movable retractable precast beam up-down safety channel device, which belongs to the field of channels, and comprises a ladder body, guardrails are rotatably connected to two sides of the ladder body, one end of the ladder body is rotatably connected with a pair of bearing columns, and the other end of the ladder body is rotatably connected with a pair of supporting columns. The other end of the ladder body is rotationally connected with a bottom plate, the other ends of the pair of bearing columns are detachably connected with the bottom plate, the lower end face of the bottom plate is rotationally connected with a moving device with rollers, a supporting device is arranged on the lower side of the bottom plate, and the bottom face of the supporting device makes contact with the ground so that pressure acting on the rollers can be shared, and loss of the rollers is reduced. The service life of the roller is prolonged; and through the first clamping groove and the second clamping groove formed in the bearing beam and the bearing plate correspondingly and the connection relation of all the components, the whole device can be conveniently stored, so that long-distance transportation is facilitated, the occupied space during placement is reduced, and the use convenience is improved.

Description

Technical Field

[0001] The utility model relates to the field of passages, and more specifically to a movable retractable prefabricated beam upper and lower safety passage device. Background Art

[0002] Climbing access devices are often used in many construction site scenarios (such as material delivery, loading and unloading, crossing the ground with a certain height difference, etc.). One of the commonly used climbing access devices in life is a climbing ladder. In order to facilitate the reuse and movement of tools, it is customary to set the ladder to be movable. During the design process, wheels, folding, guardrails, materials, balance and other aspects are generally considered to improve the comprehensive performance of the product, so as to meet the needs of users as much as possible.

[0003] However, this type of wheeled ladder has the following disadvantages during use: for a ladder equipped with rollers, generally only the wheels are in contact with the ground during use. During use, it is inevitable that heavy people will pass over it, and even workers may pass over it with heavy loads. In this way, the rollers may be easily damaged or deformed due to excessive load during use, thus affecting actual use. Utility Model Content

[0004] In order to overcome the defects of the above-mentioned mobile climbing ladder, the technical problem to be solved by the utility model is to provide a movable retractable prefabricated beam upper and lower safety passage device which can share the load-bearing of the moving climbing roller.

[0005] A movable and retractable prefabricated beam upper and lower safety passage device comprises a ladder body, guardrails are rotatably connected to both sides of the ladder body, a load-bearing column is hinged on the top of the ladder body, a bottom plate is hinged on the bottom of the ladder body, the load-bearing column and the bottom plate are detachably connected, a moving device is provided on the lower end surface of the bottom plate, a supporting device is provided on the lower side of the bottom plate, and the supporting device switches to different forms to achieve contact or separation of its bottom surface with the ground.

[0006] Furthermore, the ladder body includes a pair of load-bearing beams, and a first clamping groove is provided on a side surface of the load-bearing beams located on one side of the load-bearing column. The bottom plate includes a cross plate, and the two ends of the cross plate are respectively fixedly connected with load-bearing plates. A second clamping groove is provided on the upper end surface extending away from the cross plate at the intersection of the pair of load-bearing plates and the load-bearing beams.

[0007] Furthermore, the load-bearing column and the base plate are connected in such a way that a stopper passes through the side surface of the load-bearing plate, the inside of the load-bearing column and the other side surface of the load-bearing plate in sequence, and a nut is threadedly connected to the protruding end of the stopper; the moving device includes a clamping wheel and a roller that are rotatably connected to each other, and the clamping wheel is rotatably connected to the lower end surface of the base plate.

[0008] Furthermore, the supporting device comprises a square first supporting portion, and a side surface of the first supporting portion is hinged to the lower end surface of the base plate through a damping hinge.

[0009] Furthermore, a side surface of the first support portion opposite to the damping hinge 1 extends along the axial direction of the rotating shaft of the damping hinge 1 to form a protrusion 1; and the first support portion is located between the side surface and the bottom surface of the protrusion 1 to form a chamfer.

[0010] Furthermore, the supporting device includes a second elongated supporting portion, both ends of which are respectively connected to a pair of load-bearing plates via a pair of damping hinges 2; a chamfer is formed between a side surface relative to the damping hinge 2 and the bottom surface of the second supporting portion.

[0011] Furthermore, the supporting device includes a hollow connecting portion fixedly connected to the lower end of the base plate, the connecting portion is threadedly connected to a third supporting portion, and the bottom of the third supporting portion is formed with an end surface that can contact the ground.

[0012] Furthermore, the supporting device comprises an integrally formed supporting curved block and a second protrusion, and both the supporting curved block and the second protrusion are rotatably connected to the clamping wheel component.

[0013] Furthermore, the guardrail includes a pair of handrails, both ends of the handrails are rotatably connected with connecting pieces, and the other ends of the connecting pieces are rotatably connected to both sides of the ladder body; the number of connecting pieces is set to at least 4.

[0014] Furthermore, the number of the moving devices is at least 4, which are respectively arranged at the four corners of the bottom plate; the number of the supporting devices is at least 2, which are respectively arranged at the two ends of the longer side of the bottom plate.

[0015] The utility model has the following beneficial effects:

[0016] Firstly, the utility model provides a support device at the lower end of the bottom plate, and the support device can be unfolded from a storage state until the bottom surface of the support device contacts the ground, thereby sharing the pressure acting on the roller, reducing the loss of the roller, and thus increasing the service life of the roller.

[0017] Secondly, the utility model provides slot one and slot two on the load-bearing beam and the load-bearing plate respectively, and at the same time, through the mutual connection between the guardrail, the ladder body, the load-bearing beam and the load-bearing plate, it is convenient to store the entire device, thereby facilitating long-distance transportation and reducing the space occupied when placed, thereby improving the convenience of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0019] Figure 2 It is a structural schematic diagram showing a card slot of the present utility model;

[0020] Figure 3 It is a structural schematic diagram of the first embodiment of the utility model;

[0021] Figure 4 for Figure 3 A schematic diagram of the enlarged structure at A in the middle;

[0022] Figure 5 This is a schematic diagram of the storage and deployment structure of the support device of the first embodiment of the utility model;

[0023] Figure 6 It is a structural schematic diagram of the second embodiment of the utility model;

[0024] Figure 7 for Figure 6 A schematic diagram of the enlarged structure at B in the middle;

[0025] Figure 8 This is a schematic structural diagram of the third embodiment of the utility model;

[0026] Fig. 9 for Figure 8 Schematic diagram of the enlarged structure at D in the middle;

[0027] Fig.10 This is a schematic structural diagram of a support device according to a third embodiment of the present invention;

[0028] Fig.11 This is a schematic structural diagram of the fourth embodiment of the utility model;

[0029] Fig.12 for Fig.11 Schematic diagram of the enlarged structure at C in the middle;

[0030] Fig.13 It is a schematic structural diagram of the support device of the fourth embodiment of the utility model when it is stored.

[0031] Description of the numbers in the figure:

[0032] Ladder body; 11. load-bearing beam; 12. pedal; 13. slot one; 2. load-bearing column; 3. guardrail; 31. connector; 32. handrail; 4. bottom plate; 41. slot two; 42. stopper; 43. load-bearing plate; 44. cross plate; 5. moving device; 51. roller; 6. supporting device; 601. connecting part; 602. third supporting part; 61. first supporting part; 62. protrusion one; 63. damping hinge one; 64. second supporting part; 65. damping hinge two; 66. supporting curved block; 67. protrusion two; 68. supporting curved surface; 69. surface tail. DETAILED DESCRIPTION

[0033] In order to better understand the purpose, structure and function of the utility model, the following is a further detailed description of a movable retractable prefabricated beam upper and lower safety passage device of the utility model in conjunction with the accompanying drawings.

[0034] The utility model relates to a movable retractable prefabricated beam upper and lower safety passage device, such as Figure 1 As shown, a movable retractable prefabricated beam upper and lower safety passage device includes a ladder body 1, and guardrails 3 are rotatably connected on both sides of the ladder body 1. When a person passes through it, he can hold the guardrails 3 to prevent the person from falling from the side of the ladder, thereby improving the safety of the device. A pair of load-bearing columns 2 are hinged on the top of the ladder body 1, and the other end of the pair of load-bearing columns 2 relative to the end connected to the ladder body 1 is detachably connected to a bottom plate 4, and the bottom of the ladder body 1 is hinged to the bottom plate 4, so that the ladder body 1, the load-bearing columns 2 and the bottom plate 4 together form a triangular stable structure, and the lower end surface of the bottom plate 4 is rotatably connected to a moving device 5, and a supporting device 6 is also provided on the lower side of the bottom plate 4.

[0035] When in use, the bottom surface of the supporting device 6 is in contact with the ground, sharing the load-bearing force of the mobile device 5, thereby reducing the loss of the mobile device 5 during use, thereby extending the life of the mobile device 5, allowing the mobile device 5 to exert its advantage of being able to realize the movement of the entire safety passage device for a longer period of time.

[0036] like Figure 1 As shown, the ladder body 1 includes a pair of load-bearing beams 11 parallel to each other, and a plurality of pedals 12 are connected between the pair of load-bearing beams 11 for workers to step on; the guardrail 3 includes a pair of handrails 32 arranged on both sides of the ladder body 1, the handrail 32 is rotatably connected to one end of a connecting member 31, and the other end of the connecting member 31 is rotatably connected to the side wall of the load-bearing beam 11; the number of connecting members 31 is at least four, which are respectively arranged at the two ends of a pair of handrails 32. In actual production, the number of connecting members 31 can be increased between two connecting members 31 on the handrail 32 as needed to improve the safety performance of the guardrail 3.

[0037] like Figure 2As shown, the bottom plate 4 can be composed of a certain number (such as 2-4 pieces) of cross plates 44 connecting two load-bearing plates 43 (a U-shaped structure is formed between the two load-bearing plates 43 and the cross plates 44), and the bottom plate 4 can also be an integrally formed U-shaped structure. A pair of load-bearing columns 2 are detachably connected to a pair of load-bearing plates 43 on the base plate 4 through a stopper 42. The connection method between the load-bearing columns 2 and the load-bearing plates 43 is that a threaded stopper 42 passes through the side of the load-bearing plate 43, the interior of the load-bearing column 2 and the other side of the load-bearing plate 43 in sequence. An end cap is formed at one end of the stopper 42, and the other end can be threaded into a nut 45 until it abuts against the side of the load-bearing plate 43 to prevent the stopper 42 from slipping out of the load-bearing beam 11 during use; a fixing groove (not shown in the figure) can also be opened on the base plate 4 to allow the end of the load-bearing column 2 that contacts the base plate 4 to be inserted into the fixing groove. As long as the load-bearing column 2 and the base plate 4 can be firmly connected and the load-bearing column 2 and the base plate 4 can be detachably connected, it can be applied. A pair of load-bearing beams 11 are provided with a slot 13 on the other end face opposite to the workers' passage, and the size of the circumferential opening formed by the slot 13 is slightly larger than the circumferential size of the load-bearing column 2. Therefore, when storing, the pair of load-bearing columns 2 can be inserted into the slot 13 on the load-bearing beam 11, and a slot 2 41 is provided on the upper end face of the bottom plate 4 from the intersection of the load-bearing beam 11 and the bottom plate 4 along the U-shaped opening direction of the bottom plate 4. The number of the slots 2 41 on the bottom plate 4 is two opposite each other. In order to allow the load-bearing beam 11 to be completely inserted into the slot 2 41, the end faces of the free ends of the pair of load-bearing plates 43 away from the cross plate 44 can be set as openings; when storing, the load-bearing beam 11 that has been inserted into the load-bearing column 2 can be rotated along the rotational connection end between the load-bearing column 2 and the bottom plate 4 toward the bottom plate 4 and inserted into the slot 2 41 on the bottom plate 4, thereby facilitating the storage of the entire safety passage device and facilitating the workers to load and transport the safety passage device over long distances.

[0038] The movable device 5 is preferably a universal wheel that can freely switch directions. The universal wheel is composed of a roller 51 and a clamping wheel 52 that are rotatably connected to each other. The number of universal wheels is at least 4, and preferably 6, that is, three movable devices 5 are evenly arranged on the lower end surfaces of the two load-bearing plates 43 on the base plate 4 along the long side direction of the load-bearing plates 43; the overall height of the supporting device 6 when it is in a supporting role is not lower than the overall height of the movable device 5, so that the supporting device 6 can smoothly share the gravity acting on the movable device 5 when in use.

[0039] like Figure 3 , Figure 4 and Figure 5 This is the first embodiment of the movable retractable prefabricated beam upper and lower safety passage device of the utility model, such as Figure 3-5As shown, the support device 6 arranged below the bottom plate 4 includes a first support portion 61. The shape of the first support portion 61 can be cylindrical, square or trapezoidal. In this embodiment, it is preferably a square with different lengths and widths, and the length of the longer side is not less than the overall height of the moving device 5. The first support portion 61 is hinged to the lower end surface of the bottom plate 4 through a damping hinge 63. One end of the damping hinge 63 is connected to the lower end surface of the bottom plate 4, and the other end is connected to the upper side of the first support portion 61. The first support portion 61 is located on the side opposite to the damping hinge 63 and extends outward along the axial direction of the rotating shaft of the damping hinge 63 to form a The protrusion 62 allows the staff to use their feet to act on the protrusion 62 when opening and using the first support part 61, which is more convenient for the staff to operate; by applying a lateral force to the damping hinge 63 and parallel to the long side of the load-bearing plate 43 to the protrusion 62, the first support part 61 is rotated along the damping hinge 63, thereby realizing the storage of the support device 6; by applying a longitudinal force perpendicular to the long side of the load-bearing plate 43 and away from the load-bearing plate 43 downward to the protrusion 62, the support device 6 is opened so that the bottom surface of the first support part 61 contacts the ground, thereby realizing the effect of sharing the gravity acting on the mobile device 5.

[0040] The side of the first support part 61 that contacts the ground is the bottom surface, and a chamfer can be set between the bottom surface and the side surface of the protrusion 62, and the distance between the bottom surface and the bottom plate 4 is equal to the length of the longer side of the square first support part 61, so that the bottom surface of the first support part 61 can be in smooth contact with the ground when the first support part 61 is opened; the first support part 61 can be made of hard carbon steel, and in order to avoid the uncomfortable sound of the metal when contacting the bottom surface, soft rubber can also be set on the end surface that contacts the ground. The number of support devices 6 in this embodiment is at least four, and the setting position is preferably set near the mobile device 5 at the four corners below the bottom plate 4, so that it is more convenient for the support device 6 to share the gravity acting on the mobile device 5.

[0041] When the movable and retractable prefabricated beam upper and lower safety passage device with the above structure is in use, downward pressure can be applied to the protrusion 62 to make the first support part 61 rotate along the damping hinge 63 until the bottom surface of the first support part 61 contacts the ground, thereby sharing the gravity acting on the mobile device 5, thereby reducing the loss of the mobile device 5, extending the service life of the mobile device 5, and to a certain extent reducing the waste of resources and improving product utilization; when it is necessary to store or move the device, a lateral force can also be applied to the protrusion 62 or the first support part 61 to make the first support part 61 rotate along the damping hinge 63 and be retracted, so that the first support part 61 can be put down when it is needed, and the support device 6 can be folded when the safety passage device needs to be moved or stored and transported, thereby improving the convenience of use.

[0042] like Figure 6 and Figure 7 The second embodiment of the utility model is shown. The difference from the first embodiment is that the square first support part 61 in the support device 6 is replaced by a long strip second support part 64. The transverse section perpendicular to the second support part 64 is a square with different lengths and widths, and the length of the longer side is not less than the overall height of the support device 6. The two ends of the second support part 64 are respectively hinged to the lower end surface of a pair of load-bearing plates 43 through a pair of damping hinges 2 65; the rest of the structure and connection relationship of this embodiment are the same as those of the first embodiment, and will not be repeated here. When in use, the second support part 64 can be opened or retracted by acting on the second support part 64 exposed between the pair of load-bearing plates 43; the long strip bottom surface of the second support part 64 increases the contact area between the bottom surface of the support device 6 and the ground, thereby sharing more gravity, improving the service life of the mobile device 5, and to a certain extent, also increasing the stability of the entire safety passage. A chamfer is formed between one side of the damping hinge 2 65 and the bottom surface of the second support part 64, which facilitates the contact between the bottom surface of the second support part 64 and the ground. In this embodiment, because the two ends of the long strip-shaped second support portion 64 are respectively connected to the load-bearing plate 43, the supporting effect of a single second support portion 64 is much greater than the supporting effect of a single first support portion 61, so the number of support devices 6 of the second embodiment can be considered to be 2-3, and the setting position is preferably first set at the two ends of the longer sides of the load-bearing plate 43 on the base plate 4.

[0043] Figure 8 , Fig. 9 and Fig.10 The third embodiment of the utility model is shown. The support device 6 of this embodiment includes a hollow connection part 601 arranged on the lower end surface of the bottom plate 4. One end of the connection part 601 is fixedly connected to the bottom plate 4. A cavity for accommodating the support part is formed inside the connection part 601. The inner side wall of the cavity is provided with an internal thread. The upper part of the side wall of the third support part 602 is provided with an external thread. The third support part 602 is threadedly connected to the connection part 601 through the cavity. The other end of the third support part 602 connected to the cavity is formed with an end surface that can contact the ground. The connection depth between the third support part 602 and the connection part 601 can be adjusted by rotation so that the end surface of the third support part 602 can contact or separate from the ground. The number of support devices 6 in this embodiment is at least 4, which are arranged near the support devices 6 at the four corners of the lower end surface of the bottom plate 4.

[0044] like Fig.11 , Fig.12 and Fig.13 The fourth embodiment of the utility model is shown. Different from the above three embodiments, the support device 6 of this embodiment is not directly connected to the lower end surface of the base plate 4, but is rotatably connected to the clamping wheel member 52 of the universal wheel, so that the support device 6 of this embodiment can be changed with the rotation direction of the universal wheel.

[0045] The supporting device 6 of this embodiment includes an integrally formed protrusion 67 and a supporting curved block 66. Fig.13 A supporting curved surface 68 is formed on the side of the supporting curved block 66 that is recessed toward the roller 51. The virtual inner radius of the supporting curved surface 68 is the same as the radius of the roller 51, so that the supporting curved surface 68 fits the wheel surface of the roller 51 when in use; a surface tail 69 is formed at the end of the supporting curved surface 68, and an end surface that can contact the ground is formed at the lower part of the supporting curved block 66. When the supporting curved block 66 rotates downward to make the supporting curved surface 68 fit the wheel surface of the roller 51, the lower end surface of the supporting curved block 66 also contacts the ground; and at this time, the virtual diameter of the roller 51 perpendicular to the ground just intersects with the surface tail 69 at the end of the supporting curved surface 68, so that the supporting curved block 66 shares the gravity acting on the roller 51; at the same time, in addition to sharing the gravity, the supporting device 6 of this embodiment can also serve as a brake for the roller 51. Fig.12 In order to drive the support device 6 to rotate upward along the axis when an upward force is applied to the protrusion 67, so that the support curved surface 68 is away from the roller 51, when the support curved surface 68 is in a state of being in contact with the wheel surface of the roller 51, the protrusion 67 forms a certain angle (for example, 30° to 60°) with the bottom plate 4 or the parallel surface of the bottom plate 4.

[0046] The second protrusion 67 and the supporting curved block 66 are tightly rotationally connected to the clamping wheel part 52, so that the supporting device 6 can be stopped at will according to actual needs during the rotation along the shaft. When the supporting function of the supporting device 6 is needed, pressure can be applied to the supporting curved block 66 in the direction of the roller 51 to rotate the supporting device 6 along the shaft toward the roller 51 until the supporting curved surface 68 fits the wheel surface of the roller 51. At this time, the lower end surface of the supporting curved block 66 just contacts the ground, so that the supporting device 6 shares the gravity acting on the roller 51. When the supporting device 6 is to be stored, an upward force can be applied to the second protrusion 67 to rotate the entire supporting device 6 upward along the shaft, so that the supporting curved surface 68 on the supporting curved block 66 leaves the wheel surface of the roller 51, and the bottom end surface of the supporting curved block 66 is also separated from the ground, thereby achieving the purpose of storing the supporting device 6.

[0047] Because the support curved surface 68 is in contact with the wheel surface of the roller 51, in order to prevent the support curved block 66 from deforming during the load-bearing process and rigidly pressing the roller 51, a layer of elastic rubber can also be added to the support curved surface 68. When the elastic rubber is in contact with the wheel surface of the roller 51, the bottom end surface of the support curved block 66 is also in contact with the ground. It should be noted that the surface tail 69 of the support curved block 66 in the supporting state of this embodiment can not only intersect with the virtual radius of the roller 51 perpendicular to the ground, but also continue to extend appropriately in the horizontal direction to increase the contact area between the bottom surface and the ground, thereby improving the support stability. In addition, since the support device 6 of this embodiment is connected to the mobile device 5, the number of support devices 6 is preferably equal to the number of mobile devices 5 (for example, at least 4). However, when the entire safety passage device is relatively large and the number of mobile devices 5 increases, the number of support devices 6 can also be appropriately reduced.

[0048] The above is only a preferred specific implementation of the utility model; however, the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solution and improved ideas of the utility model within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model.

Claims

1. A movable retractable prefabricated beam upper and lower safety passage device, comprising a ladder body (1), guardrails (3) are rotatably connected to both sides of the ladder body (1), a load-bearing column (2) is hingedly connected to the top of the ladder body (1), a bottom plate (4) is hingedly connected to the bottom of the ladder body (1), the load-bearing column (2) and the bottom plate (4) are detachably connected, and a moving device (5) is provided on the lower end surface of the bottom plate (4), characterized in that: A supporting device (6) is provided on the lower side of the bottom plate (4), and the supporting device (6) switches to different forms to achieve contact or separation of its bottom surface with the ground.

2. The movable retractable prefabricated beam upper and lower safety passage device according to claim 1 is characterized in that: The ladder body (1) comprises a pair of load-bearing beams (11), and the pair of load-bearing beams (11) are provided with a first clamping groove (13) on one side of a load-bearing column (2). The bottom plate (4) comprises a transverse plate (44), and the two ends of the transverse plate (44) are respectively fixedly connected with a load-bearing plate (43), and a second clamping groove (41) is provided on the upper end surface of the side away from the transverse plate (44) extending from the intersection of the pair of load-bearing plates (43) and the load-bearing beams (11).

3. The movable retractable prefabricated beam upper and lower safety passage device according to claim 2 is characterized in that: The load-bearing column (2) and the bottom plate (4) are connected in such a way that a stopper (42) passes through the side surface of the load-bearing plate (43), the interior of the load-bearing column (2) and the other side surface of the load-bearing plate (43) in sequence, and a nut (45) is threadedly connected to the protruding end of the stopper (42); the moving device (5) comprises a clamping wheel (52) and a roller (51) which are rotatably connected to each other, and the clamping wheel (52) is rotatably connected to the lower end surface of the bottom plate (4).

4. The movable retractable prefabricated beam upper and lower safety passage device according to claim 3 is characterized in that: The support device (6) comprises a square first support portion (61), and a side surface of the first support portion (61) is hingedly connected to the lower end surface of the bottom plate (4) via a damping hinge 1 (63).

5. The movable retractable prefabricated beam upper and lower safety passage device according to claim 4 is characterized in that: A side surface of the first support portion (61) opposite to the damping hinge 1 (63) is extended along the axial direction of the rotating shaft of the damping hinge 1 (63) to form a protrusion 1 (62); the first support portion (61) is formed with a chamfer between the side surface and the bottom surface of the protrusion 1 (62).

6. The movable retractable prefabricated beam upper and lower safety passage device according to claim 3 is characterized in that: The support device (6) comprises a second support portion (64) in an elongated shape, and two ends of the second support portion (64) are respectively connected to a pair of the load-bearing plates (43) via a pair of second damping hinges (65); a chamfer is formed between a side surface of the second damping hinge (65) and a bottom surface of the second support portion (64).

7. The movable retractable prefabricated beam upper and lower safety passage device according to claim 3 is characterized in that: The support device (6) comprises a hollow connection portion (601) fixedly connected to the lower end of the bottom plate (4); the connection portion (601) is threadedly connected to a third support portion (602); and the bottom of the third support portion (602) is formed with an end surface that can contact the ground.

8. The movable retractable prefabricated beam upper and lower safety passage device according to claim 3 is characterized in that: The support device (6) comprises an integrally formed support curved block (66) and a second protrusion (67), wherein both the support curved block (66) and the second protrusion (67) are rotatably connected to the clamping wheel component (52).

9. The movable retractable prefabricated beam upper and lower safety passage device according to claim 1 is characterized in that: The guardrail (3) comprises a pair of handrails (32), the two ends of the pair of handrails (32) are rotatably connected to connecting pieces (31), and the other ends of the connecting pieces (31) are rotatably connected to two sides of the ladder body (1); the number of the connecting pieces (31) is at least four.

10. A movable retractable prefabricated beam upper and lower safety passage device according to any one of claims 1 to 9, characterized in that: The number of the moving devices (5) is at least four, which are respectively arranged at the four corners of the bottom plate (4); the number of the supporting devices (6) is at least two, which are respectively arranged at the two ends of the longer side of the bottom plate (4).

Images