An adjustable boarding ladder device

Abstract

The application provides an adjustable boarding ladder device, belonging to the technical field of ship engineering, comprising a ladder body and a clamping mechanism. The ladder body comprises an outer ladder and an inner ladder, the outer ladder is internally provided with a receiving cavity, the inner ladder is slidingly connected in the receiving cavity, a clamping assembly is installed at the top end, a supporting assembly is arranged at the bottom, the outer ladder and the inner ladder are provided with anti-skid climbing grooves along the height direction, the clamping mechanism realizes quick locking and releasing of the inner ladder and the outer ladder through a clamping block, an extension spring, a U-shaped connecting plate, a pull rod, an oval disc and a releasing assembly, the releasing assembly is designed in an arc-shaped spiral groove and a driving block, and the operation is simple. The clamping assembly is fixed to a ship body rabbet through an elastic U-shaped clamping plate and a threaded rod, and the supporting assembly enhances the stability through a torsion spring and an anti-skid inclined supporting plate. The application solves the problems of laborious manual adjustment and low efficiency of the existing boarding ladder, improves the operation convenience, safety and environmental adaptability through a quick adjustment mechanism and a stable fixing structure, and is suitable for diversified ships and complex sea conditions.

Description

Technical Field

[0001] This invention relates to the field of marine engineering technology, and in particular to an adjustable boarding ladder device. Background Technology

[0002] In shipbuilding and shipbuilding, boarding ladders are essential equipment used to facilitate personnel access to the ship's deck from the dock or water. They are typically installed on the hull side or deck area. The primary function of boarding ladders is to provide a safe and stable climbing route for crew members, while also supporting equipment handling and emergency evacuation. With the diversification of ship design and usage scenarios, boarding ladders need to be adjustable to adapt to different water levels, ship types, and dock conditions. They also require ease of installation, disassembly, and maintenance to meet the needs of frequent berthing and departure operations. Existing boarding ladders mostly employ fixed or partially adjustable designs, but their functionality and environmental adaptability still have certain limitations.

[0003] A shipboard ladder is a climbing device used to connect a ship's deck to a dock or water surface, typically consisting of a ladder, supporting structure, and fixing devices. Its main function is to provide a safe passage for boarding and disembarking, especially when ships are docked or test vessels frequently berth at docks. Traditional shipboard ladders are mostly of fixed length or have a simple detachable structure, with some designs achieving height adjustment through telescopic or splicing methods. However, in practical use, shipboard ladders need to cope with changes in water level, ship rolling, and harsh marine environments, while ensuring ease of operation and safety. Existing adjustable shipboard ladders have made some progress in design, but some technical shortcomings still exist, limiting their application in complex scenarios.

[0004] Regarding the adjustable boarding ladder described in application number 202410851788.0 (CN 118529207 A), its length adjustment device achieves relative sliding adjustment between the inner and outer ladders through an adjusting screw and an operating window. However, this design suffers from operational complexity: manually rotating the adjusting screw requires considerable physical strength, resulting in low operational efficiency, especially in frequent adjustments or emergency situations, making it difficult to meet the needs of rapid adjustment. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0007] The technical problem to be solved by the present invention is the complexity of operation of existing adjustable boarding ladder length adjustment devices.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an adjustable boarding ladder device, comprising,

[0009] The ladder body includes an outer ladder with a storage cavity inside. An inner ladder is slidably connected inside the storage cavity. Clamping components are symmetrically installed on the left and right sides of the top of the inner ladder. A support component is provided at the bottom of the outer ladder. The outer and inner ladders have several external and internal climbing grooves along their height direction for climbing. The storage cavity has symmetrical slots on the left and right sides. The bottom of the inner ladder has a rotating cavity, and the rotating cavity has symmetrical telescopic grooves on the left and right sides.

[0010] The locking mechanism includes locking blocks adapted to the locking slots on the left and right sides of the storage cavity. The opposite ends of the two locking blocks extend into the two telescopic slots and are fixedly connected to telescopic springs. The other ends of the two telescopic springs are fixedly connected to the inner walls of the two telescopic slots. U-shaped connecting plates are fixedly installed on the opposite surfaces of the two locking blocks and outside the two telescopic springs. The opposite ends of the two U-shaped connecting plates extend into the rotating cavity and are hinged to pull rods. Elliptical disks are hinged to the opposite surfaces of the two pull rods. The elliptical disks are rotatably connected to the center of the rotating cavity through a rotating shaft at the front end. A release component is provided at the rear end of the elliptical disks.

[0011] In a preferred embodiment of the adjustable boarding ladder device of the present invention, the clamping assembly includes a U-shaped clamping plate fixedly installed at the top of the inner ladder. The U-shaped clamping plate includes a clamping groove with an opening facing downwards. A clamping plate that can move back and forth is provided on the rear side inside the clamping groove. A threaded rod is rotatably connected to the rear end of the clamping plate. The rear end of the threaded rod is threadedly connected to the rear plate of the U-shaped clamping plate, and a knob is fixedly connected to the rear end of the threaded rod extending to the outside of the U-shaped clamping plate.

[0012] As a preferred embodiment of the adjustable boarding ladder device of the present invention, the support assembly includes a round rod fixedly connected to the center of the bottom of the outer ladder, torsion springs fixedly connected to the left and right side walls of the round rod, an inclined support plate fixedly connected between the two torsion springs, and anti-slip textures provided on the bottom of the inclined support plate.

[0013] As a preferred embodiment of the adjustable boarding ladder device of the present invention, the slots on the left and right sides of the storage cavity are provided at equal intervals from top to bottom along the height direction. Each set of slots includes two slots that are symmetrical on the left and right, and each set of slots is located between two adjacent outer boarding ladder slots.

[0014] As a preferred embodiment of the adjustable boarding ladder device of the present invention, protective rods are symmetrically installed on the left and right sides of the front end of the outer ladder and the inner ladder. First through slots are symmetrically opened on the left and right sides of the front surface of the outer ladder, and the two protective rods at the front end of the inner ladder are slidably connected in the two first through slots respectively.

[0015] In a preferred embodiment of the adjustable boarding ladder device of the present invention, the release component includes a rotating cylinder fixedly installed at the center of the rear end of the elliptical disk, a button slidably connected to the rear end inside the rotating cylinder, two arc-shaped spiral grooves arranged circumferentially on the outer surface of the rotating cylinder, and drive blocks adapted to the two arc-shaped spiral grooves are symmetrically installed on the left and right sides of the front end of the button, and the two drive blocks are slidably connected to the initial ends inside the two arc-shaped spiral grooves respectively.

[0016] In a preferred embodiment of the adjustable boarding ladder device of the present invention, a second through slot is provided at the center of the rear end of the outer ladder, and the rotating cylinder and the button both pass through the second through slot and extend to the outside of the outer ladder.

[0017] As a preferred embodiment of the adjustable boarding ladder device of the present invention, the inner ladder is provided with limit rods symmetrically installed at the rear end and on the left and right sides of the button, and the outer surfaces of the two limit rods are slidably connected with sliding sleeves, and the opposite surfaces of the two sliding sleeves are fixedly connected to the outer wall of the button through connecting rods.

[0018] The beneficial effects of this invention are as follows: Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0020] Figure 1 This is a perspective front view of the boarding ladder of the present invention;

[0021] Figure 2 This is a three-dimensional enlarged view of the connection between the support component and the external ladder in this invention;

[0022] Figure 3 This is a perspective enlarged view of the clamping component of the present invention;

[0023] Figure 4 This is a three-dimensional rear view of the boarding ladder of the present invention;

[0024] Figure 5 This is a perspective view of the inner ladder of the present invention;

[0025] Figure 6 This is a perspective view of the outer ladder of the present invention;

[0026] Figure 7 This is a perspective sectional view of the connection between the snap-fit ​​mechanism of the present invention and the inner and outer ladders;

[0027] Figure 8 This is a perspective view of the snap-fit ​​mechanism of the present invention;

[0028] Figure 9 This is a top sectional view of the connection between the snap-fit ​​mechanism and the inner ladder of the present invention. Detailed Implementation

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0031] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0032] Example

[0033] Reference Figures 1-9 This invention provides an adjustable boarding ladder device, which aims to overcome the shortcomings of existing boarding ladders, such as laborious manual adjustment, low efficiency, and susceptibility to corrosion in the marine environment, through an innovative length adjustment mechanism and a stable fixing structure.

[0034] The device includes a ladder body 100 and a locking mechanism 200. Through the sliding engagement of the inner ladder 102 and the outer ladder 101, and the quick locking and releasing function of the locking mechanism 200, the length of the ladder can be conveniently adjusted. Simultaneously, combined with the clamping assembly 103 and the support assembly 104, it ensures the safety and stability of the boarding ladder between the ship's deck and the dock. The following detailed description, along with a brief overview of the technical solution, explains the structure, function, and working principle of the invention, and provides supplementary optimizations to enhance its practicality.

[0035] The ladder body 100 is the core structure of the boarding ladder, including an outer ladder 101 and an inner ladder 102. The outer ladder 101 has a storage cavity 101a to accommodate the inner ladder 102 and allow it to slide within it, thus enabling flexible adjustment of the ladder length. The outer ladder 101 and inner ladder 102 are respectively provided with several outer ladder slots 101b and inner ladder slots 102a along the height direction. These slots are made of 304 stainless steel, stamped into a serrated anti-slip structure, providing stable footholds for climbers, suitable for wet or oily environments in the ocean. To enhance durability, the surface of the ladder slots is coated with an anti-salt spray coating, extending their service life. The storage cavity 101a has multiple sets of slots 101c symmetrically opened on the left and right sides. Each set of slots includes two symmetrical embedded square slots, which are evenly distributed along the height direction (for example, one set every 15cm). Each set of slots 101c is located between two adjacent external ladder slots 101b to avoid interfering with the climbing function, while ensuring that the locking points of the locking mechanism 200 are evenly distributed.

[0036] The inner ladder 102 has a rotating cavity 102b at its bottom to accommodate the moving parts of the locking mechanism 200. Symmetrical telescopic grooves 102c are formed on both sides of the rotating cavity 102b to provide space for the sliding of the locking block 201. Protective rods 105 are symmetrically installed on the left and right sides of the front ends of the outer ladder 101 and the inner ladder 102. First through grooves 101d are symmetrically formed on both sides of the front surface of the outer ladder 101. The two protective rods 105 at the front end of the inner ladder 102 are slidably connected within the first through grooves 101d, guiding the sliding direction of the inner ladder 102 and ensuring stability during adjustment. The protective rods 105 are made of high-strength aluminum alloy with a fluorescent coating to enhance visibility at night or in low-visibility environments. To further improve safety, a removable soft protective sleeve can be added to the protective rods 105 to increase grip comfort and prevent hand slippage.

[0037] The locking mechanism 200 is a key component for adjusting the length of the ladder, including locking blocks 201, telescopic springs 202, U-shaped connecting plates 203, pull rods 204, elliptical discs 205, rotating shafts 206, and release components 207. Locking blocks 201 are square blocks that fit into locking slots 101c, with polished surfaces to reduce friction and ensure smooth insertion into the slots 101c. The opposite ends of the two locking blocks 201 extend into the telescopic groove 102c and are fixedly connected to the telescopic springs 202. The other end of the telescopic springs 202 is fixedly connected to the inner wall of the telescopic groove 102c, providing elastic restoring force to maintain the locked state of the locking blocks 201. U-shaped connecting plates 203 are fixedly installed on the opposite faces of the locking blocks 201 and outside the telescopic springs 202. The opposite ends of the U-shaped connecting plates 203 extend into the rotating cavity 102b and are hinged to the pull rods 204. The opposite faces of the two pull rods 204 are hinged to the elliptical discs 205. The elliptical disk 205 is rotatably connected to the center of the rotating cavity 102b via the front rotating shaft 206, and a release component 207 is provided at its rear end.

[0038] The release assembly 207 includes a rotating cylinder 207a fixed at the center of the rear end of the elliptical disk 205. A button 207b is slidably connected to the rear end of the rotating cylinder 207a. Two arc-shaped spiral grooves 207c are arranged in a circular array on the outer surface of the rotating cylinder 207a (each groove extends about 90 degrees along the circumference, forming a quarter spiral). Drive blocks 207d that are adapted to the arc-shaped spiral grooves 207c are symmetrically installed on the left and right sides of the front end of the button 207b. The drive blocks 207d are slidably connected to the initial end of the arc-shaped spiral grooves 207c. A second through groove 101e is opened at the center of the rear end of the outer ladder 101. The rotating cylinder 207a and the button 207b pass through the second through groove 101e and extend to the outside of the outer ladder 101, making it convenient for the operator to press. To ensure linear movement of button 207b, limit rods 208 are symmetrically installed at the rear end of inner ladder 102 and on both sides of button 207b. Sliding sleeves 209 are slidably connected to the outer surface of the limit rods 208. The sliding sleeves 209 are fixedly connected to the outer wall of button 207b via connecting rods, thus restricting the movement trajectory of button 207b. To improve ease of operation, ergonomic grooves are designed on the surface of button 207b to increase pressing comfort. A waterproof sealing ring can also be installed around button 207b to prevent seawater from seeping into the rotating cylinder 207a.

[0039] The clamping assembly 103 is used to fix the boarding ladder to the tongue and groove of the hull and is installed on the left and right sides of the top of the inner ladder 102. It includes a U-shaped clamping plate 103a, a clamping plate 103b, a threaded rod 103c, and a knob 103d. The U-shaped clamping plate 103a is made of a high-strength elastic material (such as spring steel) and has a clamping groove 103a1 with an opening facing downward. The clamping plate 103b, which can move back and forth, is provided on the rear side inside the clamping groove 103a1. The rear end of the clamping plate 103b is rotatably connected to the threaded rod 103c. The rear end of the threaded rod 103c is threadedly connected to the rear plate of the U-shaped clamping plate 103a, and its rear end extends to the outside of the U-shaped clamping plate 103a and is fixedly connected to the knob 103d. In use, the top of the ladder body 100 is placed against the edge of the hull, and the U-shaped clamping plate 103a is secured to the tongue and groove joint. Turning the knob 103d rotates the threaded rod 103c, which pushes the clamping plate 103b forward, pressing it against the inner wall of the hull and securing the ladder body 100. The inner side of the clamping plate 103b is equipped with rubber pads and toothed anti-slip textures to increase friction and protect the hull surface. The threaded rod 103c is made of 316 stainless steel with an anti-corrosion coating to resist salt spray corrosion in the marine environment. To enhance adaptability, the U-shaped clamping plate 103a can be designed with an adjustable width structure, and the opening size of the clamping groove 103a1 can be adjusted by additional bolts to accommodate different tongue and groove thicknesses.

[0040] The support assembly 104, located at the bottom of the outer ladder 101, enhances stability in contact with the dock or water surface. It includes a round rod 104a, torsion springs 104b, and an inclined support plate 104c, all fixedly connected to the center of the bottom of the outer ladder 101. Torsion springs 104b are fixedly connected to the left and right side walls of the round rod 104a, and the inclined support plate 104c is fixedly connected between the two torsion springs 104b. The bottom of the inclined support plate 104c has serrated anti-slip grooves to ensure stable contact with the dock surface. The torsion springs 104b give the inclined support plate 104c the ability to rotate back and forth, adapting to the angle difference between the boarding ladder and the dock surface when tilted, ensuring complete horizontal contact between the bottom and the dock, and improving overall stability. For further optimization, the inclined support plate 104c can be designed as a detachable structure, connected to the round rod 104a via quick-release clips for easy replacement or adjustment. A high-friction coefficient rubber layer can be embedded in the bottom of the inclined support plate 104c to enhance anti-slip performance, and drainage grooves are provided at the edges to prevent water accumulation and slippage.

[0041] The working principle of this device is as follows: When the length of the boarding ladder needs to be adjusted, the operator presses button 207b. Button 207b moves linearly forward under the limiting action of sliding sleeve 209 and limiting rod 208, causing drive block 207d to slide horizontally along arc-shaped spiral groove 207c. The semi-spiral design of arc-shaped spiral groove 207c generates a lateral force, pushing rotating cylinder 207a to rotate. This causes elliptical disk 205 to rotate approximately 90 degrees around rotating axis 206. Elliptical disk 205 pulls U-shaped connecting plate 203 towards the center of rotating cavity 102b via pull rod 204, causing locking block 201 to retract into telescopic groove 102c, compressing telescopic spring 202, and releasing the locking relationship between locking block 201 and groove 101c. Inner ladder 102 can slide freely within storage cavity 101a. The operator adjusts the extension length of inner ladder 102 according to the height difference between the dock and the ship. After sliding to the appropriate height, release button 207b. The rebound force of telescopic spring 202 pushes the locking block 201 out. If the locking block 201 is not aligned with the slot 101c, it will be blocked by the inner wall of the storage cavity 101a. The operator will fine-tune the position of the inner ladder 102 until the locking block 201 is horizontally aligned with the slot 101c and locked in place. The locking block 201 drives the elliptical disk 205 to reset through the U-shaped connecting plate 203 and the pull rod 204. The rotating cylinder 207a rotates accordingly, and the arc-shaped spiral groove 207c pushes the drive block 207d and button 207b back to the initial position, preparing for the next adjustment. After adjustment, the U-shaped locking plate 103a is locked onto the hull tongue and groove. The knob 103d is rotated to adjust the clamping plate 103b to fix the ladder. The inclined support plate 104c contacts the dock to ensure stability.

[0042] This embodiment simplifies the length adjustment operation by using the arc-shaped spiral groove 207c and drive block 207d design of the snap-fit ​​mechanism 200, overcoming the drawbacks of traditional screw adjustment being laborious and prone to corrosion. The elastic U-shaped clamping plate 103a of the clamping assembly 103 and the torsion spring 104b of the support assembly 104 enhance the device's adaptability to different ship hulls and docks, giving it significant practical value and market competitiveness.

[0043] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape, and proportions of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application). For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of the invention. The order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and not only structurally equivalent but also equivalent in structure. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of the invention. Therefore, the present invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.

[0044] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the best mode of carrying out the invention as currently considered, or those features that are not relevant to implementing the invention) may be omitted.

[0045] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those skilled in the art who benefit from this disclosure, the development effort will be a routine work of design, manufacturing, and production without requiring much experimentation.

[0046] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An adjustable boarding ladder device, characterized in that: include, The ladder body (100) includes an outer ladder (101), the outer ladder (101) having a storage cavity (101a) inside, an inner ladder (102) slidably connected inside the storage cavity (101a), clamping components (103) symmetrically installed on the left and right sides of the top of the inner ladder (102), a support component (104) provided at the bottom of the outer ladder (101), the outer ladder (101) and the inner ladder (102) having a plurality of outer ladder grooves (101b) and inner ladder grooves (102a) for climbing along the height direction of the body, slots (101c) symmetrically opened on the left and right sides inside the storage cavity (101a), a rotating cavity (102b) opened at the bottom of the inner ladder (102), and telescopic grooves (102c) symmetrically opened on the left and right sides of the rotating cavity (102b); and, The latching mechanism (200) includes latching blocks (201) adapted to the latching slots (101c) on the left and right sides of the receiving cavity (101a). The opposing ends of the two latching blocks (201) extend into the two telescopic grooves (102c) and are fixedly connected to telescopic springs (202). The other ends of the two telescopic springs (202) are fixedly connected to the inner walls of the two telescopic grooves (102c). The opposing surfaces of the two latching blocks (201) are located within the two telescopic springs. A U-shaped connecting plate (203) is fixedly installed on the outside of the two U-shaped connecting plates (203). The opposite ends of the two U-shaped connecting plates (203) extend into the rotating cavity (102b) and are hinged with a pull rod (204). An elliptical disk (205) is hinged to the opposite face of the two pull rods (204). The elliptical disk (205) is rotatably connected to the center of the rotating cavity (102b) through a rotating shaft (206) at the front end. A release component (207) is provided at the rear end of the elliptical disk (205). The release assembly (207) includes a rotating cylinder (207a) fixedly installed at the center of the rear end of the elliptical disk (205). A button (207b) is slidably connected to the rear end inside the rotating cylinder (207a). Two arc-shaped spiral grooves (207c) are arranged in a circular array on the outer surface of the rotating cylinder (207a). Drive blocks (207d) that are adapted to the two arc-shaped spiral grooves (207c) are symmetrically installed on the left and right sides of the front end of the button (207b). The two drive blocks (207d) are slidably connected to the initial ends inside the two arc-shaped spiral grooves (207c). A second through slot (101e) is provided at the center of the rear end of the outer ladder (101), and the rotating cylinder (207a) and the button (207b) both pass through the second through slot (101e) and extend to the outside of the outer ladder (101); Limiting rods (208) are symmetrically installed at the rear end of the inner ladder (102) and on the left and right sides of the button (207b). Sliding sleeves (209) are slidably connected to the outer surfaces of the two limiting rods (208). The opposite surfaces of the two sliding sleeves (209) are fixedly connected to the outer wall of the button (207b) through connecting rods.

2. The adjustable boarding ladder device as described in claim 1, characterized in that: The clamping assembly (103) includes a U-shaped clamping plate (103a) fixedly installed at the top of the inner ladder (102). The U-shaped clamping plate (103a) includes a clamping groove (103a1) with an opening facing downwards. A clamping plate (103b) that can move back and forth is provided on the rear side inside the clamping groove (103a1). A threaded rod (103c) is rotatably connected to the rear end of the clamping plate (103b). The rear end of the threaded rod (103c) is threadedly connected to the rear plate of the U-shaped clamping plate (103a), and a knob (103d) is fixedly connected to the rear end of the threaded rod (103c) extending to the outside of the U-shaped clamping plate (103a).

3. The adjustable boarding ladder device as described in claim 2, characterized in that: The support assembly (104) includes a round rod (104a) fixedly connected to the center of the bottom of the outer ladder (101). Torsion springs (104b) are fixedly connected to the left and right side walls of the round rod (104a). An inclined support plate (104c) is fixedly connected between the two torsion springs (104b), and the bottom of the inclined support plate (104c) is provided with anti-slip texture.

4. The adjustable boarding ladder device as described in claim 3, characterized in that: The storage cavity (101a) has multiple sets of slots (101c) on both sides, equidistant from top to bottom along the height direction. Each set of slots (101c) includes two slots that are symmetrical on the left and right, and each set of slots (101c) is located between two adjacent external ladder slots (101b).

5. The adjustable boarding ladder device as described in claim 4, characterized in that: Protective rods (105) are symmetrically installed on the left and right sides of the front end of the outer ladder (101) and the inner ladder (102). The left and right sides of the front surface of the outer ladder (101) are symmetrically provided with first through slots (101d), and the two protective rods (105) at the front end of the inner ladder (102) are slidably connected in the two first through slots (101d).

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