Prefabricated stair

Abstract

The application relates to the technical field of building construction, and provides a fabricated stair, which comprises a plurality of stair plate assemblies, each stair plate assembly comprises a connecting rod structure, a plurality of stair plates, a synchronous assembly and a locking assembly. The connecting rod structure comprises two first connecting rods, the two first connecting rods are placed side by side, one end of the connecting rods in the length direction forms a plug-in groove, the other end forms a plug-in block matched with the plug-in groove, the side wall of the plug-in groove is rotationally connected with a first transmission shaft, one end of the first transmission shaft forms a first plug-in part in the plug-in groove, the other end is fixedly connected with a first transmission gear, the plug-in block is rotationally connected with a second transmission gear, the second transmission gear is equal in diameter to the first transmission gear, and the shaft center of the second transmission gear is provided with a plug-in hole matched with the first plug-in part; a first transmission member enables all the first transmission gears to synchronously rotate, and a second transmission member enables the first transmission gears and the second transmission gears to synchronously rotate; in this way, the stair plates between the plurality of stair plate assemblies can synchronously rotate.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, and in particular to a prefabricated staircase. Background Technology

[0002] With the development of the construction industry, prefabricated buildings have gradually gained widespread recognition. Prefabricated buildings refer to the transfer of a large amount of on-site work in traditional construction methods to factories, where building components and accessories, such as floor slabs, wall panels, stairs, and balconies, are processed and manufactured. These components are then transported to the construction site and assembled on-site using reliable connection methods.

[0003] In traditional prefabricated staircases, most are monolithic structures, which makes the transportation process inconvenient and costly, and they are not suitable for many situations; or they are made entirely of panels, which require splicing individual panels together, and the assembly process requires a lot of effort.

[0004] In existing prefabricated staircases, the structure is often broken down into multiple stair sections. Each section's stair slabs are rotatably connected to the frame. During transport, these sections are folded up, forming a flat surface. During on-site assembly, the slabs are then rotated out to create multiple steps. However, because the angle of each stair slab needs to be readjusted, differences in the inclination angles between adjacent sections can easily occur. In use, this difference in inclination angles makes it extremely easy for pedestrians to stumble or fall at the connection points between two sections.

[0005] Therefore, there is an urgent need for a prefabricated staircase to solve the above-mentioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to provide a prefabricated staircase that enables synchronous rotation of stair treads among multiple stair tread assemblies.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] Prefabricated staircase, comprising multiple interconnected stair tread assemblies, each of the aforementioned stair tread assemblies comprising:

[0009] The connecting rod structure includes two first connecting rods placed side by side. One end of the two first connecting rods along its length is formed with a insertion groove, and the other end is formed with an insertion block adapted to the insertion groove. A first drive shaft is rotatably connected to the side wall of the insertion groove. One end of the first drive shaft forms a first insertion part in the insertion groove, and the other end is fixedly connected with a first drive tooth. The insertion block is rotatably connected with a second drive tooth. The second drive tooth has the same diameter as the first drive tooth, and the axis of the second drive tooth is provided with an insertion hole adapted to the first insertion part.

[0010] After the two connecting rod structures are connected, the plug-in block of one of them is plugged into and fixed to the plug-in slot of the other, and the first plug-in part is plugged into and fixed to the plug-in hole.

[0011] Multiple stair treads are located between the two first connecting rods and are arranged sequentially and evenly between the insertion slots and the insertion blocks along the length of the first connecting rods. The stair treads are rotatably connected to the two first connecting rods via a second drive shaft. The stair treads are fixed to the second drive shaft. Each second drive shaft is fixed to at least one first drive tooth. The first drive tooth is located on the side of the first connecting rod facing away from the stair tread.

[0012] The synchronization component includes a first transmission member and a second transmission member, wherein the first transmission member causes all the first transmission teeth to rotate synchronously, and the second transmission member causes the first transmission teeth and the second transmission teeth to rotate synchronously.

[0013] The locking assembly is capable of locking the rotation angle between the stair tread and the first connecting rod.

[0014] As a preferred technical solution for the above-mentioned prefabricated staircase, the second transmission component is a third transmission tooth with the same diameter as the second transmission tooth. The third transmission tooth is coaxially fixed to the first transmission tooth adjacent to the second transmission tooth, and the third transmission tooth meshes with the second transmission tooth.

[0015] As a preferred technical solution for the aforementioned prefabricated staircase, the first insertion part is spline-shaped, and the insertion hole is a spline groove structure adapted to it.

[0016] As a preferred technical solution for the above-mentioned prefabricated staircase, the connecting rod structure further includes a second connecting rod, which is sleeved on and fixed to the first connecting rod. The insertion block of the first connecting rod is exposed outside the second connecting rod, and the first transmission gear, the second transmission gear, and the synchronization component are all located inside the second connecting rod.

[0017] As a preferred technical solution for the aforementioned prefabricated staircase, the locking assembly is inserted through the aforementioned second drive shaft. The locking assembly includes a first anti-rotation rod and a second anti-rotation rod. One end of the first anti-rotation rod forms a limiting sleeve, and an eccentric wheel is rotatably connected to the middle of the limiting sleeve. One end of the second anti-rotation rod forms a limiting block, and the limiting block is axially inserted into the limiting sleeve. The first anti-rotation rod and the second anti-rotation rod are respectively circumferentially fixed and axially slidably connected to the corresponding side of the first connecting rod. The limiting block and the limiting sleeve have a first position and a second position. When in the first position, the limiting block is located between the line connecting the two eccentric wheels, so that the two eccentric wheels abut against the aforementioned second drive shaft. When in the second position, the limiting block is located on the side of the connecting line closer to the outlet of the limiting sleeve.

[0018] As a preferred technical solution for the above-mentioned prefabricated staircase, the staircase assembly also includes a guard plate, which corresponds one-to-one with the second connecting rod and is placed parallel to it. The guard plate is rotatably connected to the second connecting rod, and the axial direction of the hinge shaft is parallel to the length direction of the second connecting rod.

[0019] As a preferred technical solution for the aforementioned prefabricated staircase, the first anti-rotation rod and the second anti-rotation rod are respectively hinged to the adjacent guard plate ball joint.

[0020] As a preferred technical solution for the above-mentioned prefabricated staircase, a connecting block is provided at one end of the length direction of the guardrail, and a slot adapted to the connecting block is provided at the other end. After the two staircase slab components are connected, the connecting block of one of them is inserted into the slot of the other, so that the two guardrails connected along the length direction can rotate synchronously.

[0021] As a preferred technical solution for the above-mentioned prefabricated staircase, it also includes a fixing plate, which connects two guardrails that are connected along the length direction.

[0022] As a preferred technical solution for the above-mentioned prefabricated staircase, it also includes a base plate, which is detachably connected to the staircase assembly. The base plate is provided with a second insertion part, which is in the shape of a spline that matches the insertion hole.

[0023] Beneficial effects of this invention:

[0024] When adjusting the rotation angle of the stair treads, rotating one stair tread causes the second drive shaft, which is fixedly connected to it, to rotate relative to the first connecting rod. The second drive shaft drives the first drive gear, which, through the first drive component, causes other first drive gears located in the same stair tread assembly to rotate synchronously, thereby causing the stair treads to rotate synchronously. Furthermore, the first drive component drives the first drive shaft to rotate through the first drive gear. Since the first insertion part formed at one end of the first drive shaft is fixedly connected to the insertion hole of another stair tread assembly, when the first drive shaft rotates, it drives the second drive gear with the insertion hole to rotate. Since the second drive gear and the first drive gear have the same diameter, and are driven by the second drive component, the second drive gear and the first drive gear rotate synchronously. Furthermore, the first drive gear drives other first drive gears to rotate through the first drive component, thereby causing the stair treads of the stair tread assembly to rotate synchronously. In this way, the stair treads of the two connected stair tread assemblies rotate synchronously. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0026] Figure 1 This is a structural schematic diagram of the stair tread assembly provided in an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of the first connecting rod provided in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the locking component provided in an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the structure of the base plate provided in an embodiment of the present invention. Figure 1 ;

[0030] Figure 5 This is a schematic diagram of the structure of the base plate provided in an embodiment of the present invention. Figure 2 ;

[0031] Figure 6 This is a schematic diagram of the structure of the base plate provided in an embodiment of the present invention. Figure 3 ;

[0032] Figure 7 This is a structural schematic diagram of the prefabricated staircase provided in an embodiment of the present invention.

[0033] In the picture:

[0034] 10. First connecting rod; 11. Insertion slot; 12. Insertion block; 13. First drive shaft; 131. First insertion part; 14. First drive tooth; 15. Second drive tooth; 151. Insertion hole;

[0035] 20. Stair tread; 21. Second drive shaft;

[0036] 31. First transmission component; 32. Second transmission component;

[0037] 40. Second connecting rod;

[0038] 50. Locking assembly; 51. First anti-rotation rod; 511. Limit sleeve; 512. Eccentric wheel; 52. Second anti-rotation rod; 521. Limit block;

[0039] 60. Protective plate; 61. Connecting block; 62. Slot;

[0040] 70. Fixing plate; 80. Base plate; 81. Mounting groove; 82. Second insertion part; 83. Connecting piece. Detailed Implementation

[0041] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0042] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0044] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0045] like Figures 1 to 7 As shown, this application provides a prefabricated staircase, including multiple interconnected stair tread assemblies, each stair tread assembly including a connecting rod structure, multiple stair treads 20, a synchronization assembly, and a locking assembly 50. The connecting rod structure includes two first connecting rods 10, which are placed side by side. One end of each first connecting rod 10 forms a insertion groove 11 along its length, and the other end forms an insertion block 12 adapted to the insertion groove 11. A first drive shaft 13 is rotatably connected to the side wall of the insertion groove 11. One end of the first drive shaft 13 forms a first insertion portion 131 within the insertion groove 11, and the other end is fixedly connected to a first drive tooth 14. The insertion block 12 is rotatably connected to a second drive tooth 15, which has the same diameter as the first drive tooth 14. The axis of the second drive tooth 15 has an insertion hole 151 adapted to the first insertion portion 131. After the two connecting rod structures are connected, the insertion block 12 of one rod is inserted into and fixed to the insertion groove 11 of the other rod, and the first insertion portion 131 is inserted into and fixed to the insertion hole 151. A stair tread 20 is located between two first connecting rods 10, and is arranged sequentially and evenly between the insertion slots 11 and the insertion blocks 12 along the length of the first connecting rods 10. The stair tread 20 is rotatably connected to the two first connecting rods 10 via a second drive shaft 21. The stair tread 20 is fixed to the second drive shaft 21, and each second drive shaft 21 is fixed to at least one first drive tooth 14. The first drive tooth 14 is located on the side of the first connecting rod 10 facing away from the stair tread 20. A synchronization component includes a first drive member 31 and a second drive member 32. The first drive member 31 causes all first drive teeth 14 to rotate synchronously, and the second drive member 32 causes the first drive teeth 14 and the second drive teeth 15 to rotate synchronously. A locking component 50 is provided, which can lock the rotation angle between the stair tread 20 and the first connecting rods 10.

[0046] During assembly, select an appropriate number of stair tread components according to the actual usage, and connect the stair tread components end to end. Specifically, first place multiple stair tread components in sequence along their length, with adjacent stair treads 20 staggered, so that the insertion block 12 on the first connecting rod 10 of one of them is inserted into the insertion slot 11 of the first connecting rod 10 of the other. After aligning the first insertion part 131 with the insertion hole 151, align the two stair tread components so that the first insertion part 131 is inserted into the insertion hole 151. After the first insertion part 131 is inserted into the insertion hole 151, relative circumferential rotation cannot occur.

[0047] When adjusting the rotation angle of the stair tread 20, rotating one of the stair treads 20 causes the second drive shaft 21, which is fixedly connected to it, to rotate relative to the first connecting rod 10. The second drive shaft 21 drives the first drive gear 14, which is fixed to it. The first drive gear 14, through the first drive member 31, causes the other first drive gears 14 located in the same stair tread assembly to rotate synchronously, thereby realizing the synchronous flipping of the stair tread 20. Furthermore, the first transmission member 31 drives the first transmission shaft 13 to rotate via the first transmission tooth 14. Since the first insertion part 131 formed at one end of the first transmission shaft 13 is fixedly connected to the insertion hole 151 of another stair tread assembly, when the first transmission shaft 13 rotates, it will drive the second transmission tooth 15 with the insertion hole 151 to rotate. Since the second transmission tooth 15 and the first transmission tooth 14 have the same diameter, they are driven by the second transmission member 32, so that the second transmission tooth 15 and the first transmission tooth 14 can rotate synchronously. Furthermore, the first transmission tooth 14 drives other first transmission teeth 14 to rotate via the first transmission member 31, thereby making the stair tread 20 of the stair tread assembly rotate synchronously. In this way, the stair treads 20 of the two stair tread assemblies connected along the length direction can rotate synchronously.

[0048] Specifically, the first transmission component 31 is a chain. When all the first transmission teeth 14 installed on the stair tread assembly are located on the same side of the same first connecting rod 10, only one transmission bar is needed to realize the transmission between all the first transmission teeth 14. Furthermore, in order to improve the accuracy of chain transmission, multiple chains can be used, and one end of two adjacent chains can mesh with the first transmission teeth 14 on the same second transmission shaft 21 for transmission.

[0049] Specifically, the second transmission component 32 is a third transmission tooth with the same diameter as the second transmission tooth 15. The third transmission tooth is coaxially fixed to the first transmission tooth 14 adjacent to the second transmission tooth 15, and the third transmission tooth meshes with the second transmission tooth 15.

[0050] Furthermore, the third transmission gear and the second transmission gear 15 are integrally formed.

[0051] Specifically, the first insertion part 131 is spline-shaped, and the insertion hole 151 is a spline groove structure adapted to it.

[0052] Optionally, the connecting rod structure also includes a second connecting rod 40, which is sleeved around and fixed to the first connecting rod 10. The insertion block 12 of the first connecting rod 10 is exposed outside the second connecting rod 40, and the first transmission gear 14, the second transmission gear 15, and the synchronization assembly are all located inside the second connecting rod 40. This design, by sleeved with the second connecting rod 40 over the first connecting rod 10, effectively embeds the transmission structure between the stair treads 20 within the second connecting rod 40, providing protection and preventing damage during transport.

[0053] Specifically, the locking assembly 50 passes through the second drive shaft 21. The locking assembly 50 includes a first anti-rotation rod 51 and a second anti-rotation rod 52. One end of the first anti-rotation rod 51 forms a limiting sleeve 511. An eccentric wheel 512 is rotatably connected to the middle of the limiting sleeve 511. One end of the second anti-rotation rod 52 forms a limiting block 521. The limiting block 521 and the limiting sleeve 511 are axially inserted. The first anti-rotation rod 51 and the second anti-rotation rod 52 are respectively fixed circumferentially and slidably connected axially to the first connecting rod 10 on the corresponding side. The limiting block 521 and the limiting sleeve 511 have a first position and a second position. When in the first position, the limiting block 521 is located between the line connecting the two eccentric wheels 512, so that the two eccentric wheels 512 abut against the second drive shaft 21. When in the second position, the limiting block 521 is located on the side of the connecting line closer to the outlet of the limiting sleeve 511. With this configuration, when adjusting the rotation angle of the stair tread 20 relative to the first connecting rod 10, the limiting block 521 is in the second position relative to the limiting sleeve 511, and the second drive shaft 21 can rotate relative to the locking assembly 50 to adjust the placement angle of the stair tread 20. After the angle adjustment is completed, the first anti-rotation rod 51 and the second anti-rotation rod 52 are pushed, causing the limiting block 521 to extend further into the limiting sleeve 511. During the movement, the limiting block 521 contacts the two eccentric wheels 512, and the friction between them drives the eccentric wheels 512. When the limit block 521 is located between the lines connecting the two eccentric wheels 512, it is considered to have reached the first position. At this time, the eccentric wheel 512 opens outward and then abuts against the second drive shaft 21. The limit sleeve 511 is locked with the second drive shaft 21, and the two cannot rotate relative to each other around the axis. Since the first anti-rotation rod 51 and the second anti-rotation rod 52 are respectively circumferentially fixed to the first connecting rod 10 on the corresponding side, the second drive shaft 21 and the first connecting rod 10 are relatively stationary, so as to lock the rotation angle of the stair tread 20 and the first connecting rod 10.

[0054] Optionally, the stair tread assembly also includes a guard plate 60, which corresponds one-to-one with the second connecting rod 40 and is placed parallel to it. The guard plate 60 and the second connecting rod 40 are rotatably connected, and the axial direction of the hinge axis is parallel to the length direction of the second connecting rod 40. With this configuration, for easy storage and handling, the guard plates 60 on both sides can be flipped to the same plane, and the stair tread 20 can be rotated and adjusted to the same plane, so that the entire stair tread assembly has a plate-like structure, and multiple stair tread assemblies can be stacked.

[0055] Optionally, the first anti-rotation rod 51 and the second anti-rotation rod 52 are respectively ball-hinged with the adjacent guard plate 60. Specifically, the guard plate 60 has multiple grooves, each corresponding to a stair tread 20. A support rod is installed in each groove, with one end fixed to the guard plate 60 and the other end ball-hinged with either the first anti-rotation rod 51 or the second anti-rotation rod 52. With this configuration, after the stair tread 20 has been angled, flipping the guard plate 60 so that it is perpendicular to the stair tread 20, and then pushing the guard plate 60 towards the side where the stair tread 20 is located, will cause the guard plate 60 to move closer to the first anti-rotation rod 51 or the second anti-rotation rod 52 connected to it, thereby completing the locking action to prevent the stair tread 20 from rotating.

[0056] Optionally, a connecting block 61 is provided at one end of the guard plate 60 along its length, and a slot 62 adapted to the connecting block 61 is provided at the other end. After two stair tread components are connected, the connecting block 61 of one component is inserted into the slot 62 of the other component, allowing the two guard plates 60 connected along the length to rotate synchronously. This configuration connects the guard plates 60 of multiple stair tread components connected along the length to each other, and enables synchronous movement during the rotation process, thereby enhancing the structural strength of the prefabricated staircase and simplifying the assembly process.

[0057] Optionally, the prefabricated staircase also includes a fixing plate 70, which connects two guardrails 60 connected along the length direction. Thus, adding a fixing plate 70 at the joint of the two guardrails 60 connected along the length direction can strengthen the connection between the two guardrails 60.

[0058] Optionally, the prefabricated staircase also includes a base plate 80, which is detachably connected to the stair tread assembly. The base plate 80 has a protruding second insertion part 82, which is splined and adapted to the insertion hole 151. Specifically, a mounting groove 81 is provided on one side edge of the base plate 80, and the second insertion part 82 protrudes from the mounting groove 81. During installation, the insertion block 12 extends into the mounting groove 81 and fixes the second insertion part 82 to the insertion hole 151. With this configuration, before the stair tread assembly is unfolded, the base plate 80 is installed on its side closest to the ground. After the second insertion part 82 of the base plate 80 is inserted into the insertion hole 151, the base plate 80 can rotate synchronously with the stair tread 20 in the stair tread assembly. Thus, by flipping the base plate 80, it can be made parallel to or flush with the ground, thereby making the stair tread 20 synchronously parallel to the ground.

[0059] It should be noted that during installation, the base plate 80 must be kept parallel to the stair tread 20.

[0060] Specifically, when the base plate 80 flips, the second insertion part 82 drives the second transmission gear 15 to rotate. The second transmission gear 15 drives the first transmission gear 14 to rotate synchronously with the help of the second transmission member 32. The first transmission gears 14 then rotate synchronously with each other through the first transmission member 31.

[0061] Furthermore, on the base plate 80, a connecting piece 83 is rotatably connected to the same side edge as the mounting groove 81. One end of the connecting piece 83 is hinged to the base plate 80, and the other end has an insertion hole 151. When the staircase layout is zigzag or meandering, the base plate 80 can serve as a transition platform between two stair tread assemblies placed in opposite directions. The second insertion part 82 of the base plate 80 is inserted into the insertion hole 151 of the floor assembly above it, while the insertion hole 151 of the connecting piece 83 is used to insert into the first insertion part 131 of the stair tread assembly below it.

[0062] Furthermore, the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A prefabricated stair, characterized in that Comprise a plurality of interconnected stair board assemblies, each of said stair board assemblies comprising: A connecting rod structure, said connecting rod structure comprises two first connecting rods (10), two said first connecting rods (10) are placed side by side, one end of the length direction forms a plug slot (11), the other end forms a plug block (12) matched with said plug slot (11), the side wall of said plug slot (11) is rotationally connected with a first transmission shaft (13), one end of said first transmission shaft (13) forms a first plug-in part (131) in said plug slot (11), the other end is fixedly connected with a first transmission gear (14), said plug block (12) is rotationally connected with a second transmission gear (15), said second transmission gear (15) is equal in diameter with said first transmission gear (14), the shaft center of said second transmission gear (15) is provided with a plug hole (151) matched with said first plug-in part (131); After two said connecting rod structures are connected, the plug block (12) of one is plugged into and fixed with the plug slot (11) of the other, and the first plug-in part (131) is plugged into and fixed with the plug hole (151); A plurality of stair boards (20) are located between two said first connecting rods (10) and are sequentially and uniformly arranged between said plug slot (11) and said plug block (12) along the length direction of said first connecting rod (10), said stair board (20) is rotationally connected with two said first connecting rods (10) through a second transmission shaft (21), said stair board (20) is fixed with said second transmission shaft (21), each said second transmission shaft (21) is fixed with at least one said first transmission gear (14), said first transmission gear (14) is located on the side of said first connecting rod (10) away from said stair board (20); A synchronization assembly comprises a first transmission member (31) and a second transmission member (32), said first transmission member (31) is a chain; said first transmission member (31) synchronously rotates all said first transmission gears (14), said second transmission member (32) synchronously rotates said first transmission gears (14) and said second transmission gears (15); said second transmission member (32) is a third transmission gear equal in diameter with said second transmission gear (15), said third transmission gear is coaxially fixed to said first transmission gear (14) adjacent to said second transmission gear (15), said third transmission gear is engaged with said second transmission gear (15); A locking assembly (50) can lock the rotation angle between said stair board (20) and said first connecting rod (10).

2. The prefabricated stair according to claim 1, characterized in that Said first plug-in part (131) is a spline, and said plug hole (151) is a spline groove structure matched with said first plug-in part (131).

3. The prefabricated stair according to claim 2, characterized in that The connecting rod structure further comprises a second connecting rod (40) sleeved on and fixed with the first connecting rod (10), and the plug-in block (12) of the first connecting rod (10) is exposed outside the second connecting rod (40), and the first transmission tooth (14), the second transmission tooth (15) and the synchronization assembly are located in the second connecting rod (40).

4. The prefabricated stair according to claim 3, characterized in that The locking assembly (50) is arranged on the second transmission shaft (21), and the locking assembly (50) comprises a first rotation-stopping rod (51) and a second rotation-stopping rod (52), one end of the first rotation-stopping rod (51) forms a limiting sleeve (511), the middle part of the limiting sleeve (511) is rotationally connected with an eccentric wheel (512), one end of the second rotation-stopping rod (52) forms a limiting block (521), the limiting block (521) is axially inserted with the limiting sleeve (511), the first rotation-stopping rod (51) and the second rotation-stopping rod (52) are circumferentially fixed and axially slidably connected with the first connecting rod (10) on the corresponding side, the limiting block (521) and the limiting sleeve (511) comprise a first position and a second position, when being in the first position, the limiting block (521) is located between the connecting line of the two eccentric wheels (512), so that the two eccentric wheels (512) abut against the second transmission shaft (21), when being in the second position, the limiting block (521) is located on the side of the connecting line close to the outlet of the limiting sleeve (511).

5. The prefabricated stair according to claim 4, characterized in that The stair plate assembly further comprises a guard plate (60), the guard plate (60) corresponds to the second connecting rod (40) one by one and is placed in parallel with the second connecting rod (40), the guard plate (60) is rotationally connected with the second connecting rod (40), and the axial direction of the hinge shaft is parallel to the length direction of the second connecting rod (40).

6. The prefabricated stair according to claim 5, characterized in that The first rotation-stopping rod (51) and the second rotation-stopping rod (52) are respectively ball-hingedly connected with the adjacent guard plate (60).

7. The prefabricated stair according to claim 5, characterized in that One end of the length direction of the guard plate (60) is provided with a connecting block (61), and the other end is provided with a clamping groove (62) matched with the connecting block (61), after the two stair plate assemblies are connected, the connecting block (61) of one of the two stair plate assemblies is inserted with the clamping groove (62) of the other, so that the two guard plates (60) connected in the length direction can be synchronously rotated.

8. The prefabricated stair according to claim 7, characterized in that Further comprising a fixed plate (70) connecting the two guard plates (60) connected in the length direction.

9. The prefabricated stair according to any of claims 1-8, characterized in that Further comprising a bottom plate (80) detachably connected with the stair plate assembly, the bottom plate (80) is protrudingly provided with a second plug-in part (82), and the second plug-in part (82) is in the form of a spline matched with the plug-in hole (151).

Images