A-frame folding ladder with articulated joint support

Abstract

Disclosed in the invention is an A-frame folding ladder with articulated joint support, comprising two ladder frames symmetrically arranged. Each ladder frame is provided with a front side rail and a rear side rail, and the front side rail and the rear side rail form an "A" shaped hinge structure. A plurality of steps is arranged between the two front side rails, and the side edge of the plurality of steps is hinged to a pull rod. The A-frame folding ladder further comprises two rear side rail connecting rods symmetrically arranged. The two ends of each rear side rail connecting rod are respectively hinged to a rear side rail and a step. In the present invention, by means of the collaboration of the pull rods, the steps and the rear side rail connecting rods, the rear side rails and the steps can be driven to be flexibly folded. In addition, one end of each rear side rail connecting rod is hinged to a linkage step, and the step is firmer than the pull rod. Compared with the prior art, better support can be provided for the unfolding of the rear side rails, the linkage steps are not prone to deformation, and higher durability and reliability are achieved.

Description

A herringbone folding ladder with linked hinged support

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims: On December 20, 2023, the application number is: 202323475703.3, and the invention name is: "A linked hinged herringbone folding ladder". The Chinese patent application is based on and claims its priority. The content of the Chinese patent application is hereby introduced into the text of this application. Technical Field

[0003] The invention belongs to the technical field of foldable ladders, and in particular relates to a linked hinged herringbone foldable ladder. Background Art

[0004] In everyday life, people rely on stools or ladders to easily reach items placed high up or to load, unload, and repair electrical equipment. However, stools are not stable enough to step on, posing a significant safety hazard. Non-foldable ladders are bulky and inconvenient to store and move. Foldable ladders typically have steps hinged to the front and rear legs. These steps are not flexible enough to fold, and can easily become stuck when opened or folded halfway.

[0005] In the prior art, such as patent CN208184638U, the applicant added a pull rod between the two pedals, and the pull rod was connected to the rear leg tube through a rear leg tube connecting rod 4. In the folding ladder of this structure, when the front leg tube and the rear leg tube rotate relative to each other, the pull rod drives the pedals to fold, thereby improving the flexibility of folding the pedals. However, since the rear leg tube is connected to the pull rod, when the rear leg tube is subjected to force, the rear leg tube connecting rod 4 will correspondingly apply force to the pull rod. Over time, the pull rod is prone to deformation, affecting the durability and reliability of the folding ladder. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a linked hinged herringbone folding ladder.

[0007] The technical solutions of the present invention are as follows:

[0008] A linked hinged herringbone folding ladder comprises two symmetrically arranged ladder frames, each ladder frame having a front leg tube and a rear leg tube, the front leg tube and the rear leg tube forming a herringbone opening and closing structure, a plurality of steps being arranged between the two front leg tubes, the sides of the plurality of steps being hinged to a pull rod, and the herringbone folding ladder further comprising two symmetrically arranged rear leg tube connecting rods, the ends of the rear leg tube connecting rods being hinged to the rear leg tubes and a step respectively;

[0009] A support rod is connected between the two rear leg tubes, and the bottom of the uppermost step abuts against the support rod;

[0010] A lock is provided at the bottom of the uppermost pedal, and the lock is buckled with the support rod when the pedal is opened.

[0011] In the above technical solution, the pull rod drives the synchronous folding of multiple pedals. Through the cooperation of the pull rod, the interlocking pedals, and the rear leg tube connecting rod, the rear leg tube and the interlocking pedals can be flexibly folded. At the same time, because the hinge point is set on the interlocking pedal, the interlocking pedal is stronger than the rear leg tube connecting rod, which can provide better support for the deployment of the rear leg tube. The interlocking pedal is not easily deformed, and has higher durability and reliability. The lock buckle can be used as a handle for opening or folding the herringbone ladder, improving the convenience of use. When opened, the lock buckle is connected to the support rod to improve the stability of the pedals.

[0012] In a possible implementation, one end of the rear leg tube connecting rod hinged to the pedal is higher than one end of the rear leg tube connecting rod hinged to the rear leg tube.

[0013] In one possible implementation, the rear side section of the step hingedly connected to the rear leg tube connecting rod extends outward by a first length, and the step and the rear leg tube connecting rod are hingedly connected to the rear side section. In the above technical solution, because the rear side section of the step extends outward, the width between the two rear leg tube connecting rods is greater than the width between the two tie rods, so that the two tie rods do not overlap when the herringbone ladder is folded.

[0014] Further preferably, the front side section of the step extends outward by a second length, the step and the front leg tube are hingedly connected to the front side section, and the second length is greater than the first length. In the above technical solution, the width between the two front leg tubes is greater than the width between the two rear leg tube connecting rods. When folded, the pull rod and the rear leg tube connecting rod are stored between the two ladder frames, making the folded shape more regular and beautiful.

[0015] In one possible implementation, the length of the top pedal is greater than or equal to that of the other pedals. Furthermore, preferably, the downward projection of each pedal partially overlaps the pedal below it. In this technical solution, adjacent pedals partially overlap vertically, allowing a user to step on the next pedal if they accidentally slip, mitigating injury.

[0016] In a possible implementation, protective covers are provided on the left and right sides of the pedal. The protective covers have a rounded outer surface. In the above technical solution, by providing the protective covers on the left and right sides of the pedal, the user can be prevented from being scratched by the pedal.

[0017] The present invention can drive the rear leg tube and the pedal to fold flexibly through the cooperation of the pull rod, the pedal and the rear leg tube connecting rod. At the same time, since one end of the rear leg tube connecting rod is hinged on the connecting pedal, and the pedal is stronger than the pull rod, compared with the existing technology, it can provide better support for the deployment of the rear leg tube, and the connecting pedal is not easy to deform, and has higher durability and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic structural diagram of a herringbone folding ladder when unfolded according to an embodiment of the present invention;

[0019] Figure 2 is an enlarged view of A in Figure 1;

[0020] FIG3 is a schematic structural diagram of a herringbone folding ladder when unfolded according to an embodiment of the present invention;

[0021] FIG4 is an enlarged view of B in FIG3 ;

[0022] FIG5 is a bottom view of the folding ladder of the embodiment of the present invention when it is opened;

[0023] FIG6 is an enlarged view of C in FIG5 ;

[0024] FIG7 is a rear view of the folding ladder of the embodiment of the present invention when it is opened;

[0025] FIG8 is a rear view of a folding ladder according to an embodiment of the present invention when folded;

[0026] The reference numerals in the figure are: 1-ladder frame, 11-front leg tube, 12-rear leg tube, 121-support rod, 2-pedal, 21-protective cover, 22-front side section, 23-rear side section, 24-lock, 3-pull rod, 4-rear leg tube connecting rod. DETAILED DESCRIPTION

[0027] The technical solution of this application is further illustrated and described below through specific implementation methods.

[0028] Referring to Figures 1-4, the herringbone folding ladder includes two ladder frames 1 arranged symmetrically on both sides, a multi-step pedal 2 connected between the two ladder frames 1, a pull rod 3 connected to the side of the pedal 2 to enable the pedal 2 to move in conjunction, and a rear leg tube connecting rod 4 connecting the rear leg tube 12 and a pedal 2. The ladder frame 1 includes a front leg tube 11 and a rear leg tube 12 hinged at one end, and the front leg tube 11 and the rear leg tube 12 form a herringbone opening and closing structure. The uppermost pedal 2, the pull rod 3, the pedal 2 connected to the rear leg tube connecting rod 4, the rear leg tube connecting rod 4, and the rear leg tube 12 move in conjunction, increasing the convenience of opening and folding the herringbone folding ladder. In addition, because one end of the rear leg tube connecting rod 4 is connected to the pedal 2 rather than the pull rod 3, it can effectively prevent the rear leg tube connecting rod 4 from applying force to the pull rod 3, causing the pull rod 3 to deform, thereby improving the durability of the herringbone folding ladder.

[0029] The side covers of the pedal 2 are provided with protective covers 21. The protective covers 21 can cover the sharp corners of the pedal 2. Furthermore, by processing the protective covers 21 to extend the front side sections 22 and / or the rear side sections 23 of the pedal 2 outward, the overall shape of the pedal 2 and protective covers 21 can be changed. In other possible implementations, the protective covers 21 may not be provided, and the front side sections 22 and / or the rear side sections 23 of the pedal 2 may be directly extended.

[0030] Specifically, for the step 2 hinged to the rear leg tube connecting rod 4, its side front section 22 extends outward by a second length, and its side rear section 23 extends outward by a first length, with the second length being greater than the first length. Through the above technical solution, the step 2 has three different widths at different locations. The side front section 22 is hinged to the front leg tube 11, the side rear section 23 is hinged to the rear leg tube connecting rod 4, and the pull rod 3 is hinged between the side front section 22 and the side rear section 23. As shown in Figures 5 and 6, the positions of the front leg tube 11, the rear leg tube connecting rod 4, and the pull rod 3 are staggered to reduce mutual interference. Accordingly, the side front sections 22 of the other step 2 extend outward so that their side front sections 22 have the same width as the step 2 connected to the rear leg tube connecting rod 4. When the herringbone ladder is folded, the step 2, pull rod 3, and rear leg tube connecting rod 4 are all stored between the two ladder frames 1.

[0031] 3 , 7 and 8 , a support rod 121 is connected between the rear leg tubes 12. When the herringbone folding ladder is opened, the bottom of the uppermost step 2 abuts against the support rod 121. A rotatable lock 24 is provided at the bottom of the step 2. When the bottom of the step 2 abuts against the support rod 121, the lock 24 is buckled with the support plate.

[0032] Returning to Figure 5 , the topmost step 2 is longer than or equal to the other steps 2, and the orthographic projection of each step 2 partially overlaps the step 2 below it. Because adjacent steps 2 partially overlap vertically, if a user accidentally slips from one step 2, they can still step on the next step 2, mitigating injury.

[0033] The above description is merely a preferred embodiment of the present invention and therefore cannot be used to limit the scope of the present invention. In other words, equivalent changes and modifications made within the scope of the present invention and the contents of the specification should still fall within the scope of the present invention. Industrial Applicability

[0034] The present invention discloses a linked hinged herringbone folding ladder, comprising two symmetrically arranged ladder frames, each ladder frame having a front leg tube and a rear leg tube, the front leg tube and the rear leg tube forming a herringbone opening and closing structure, a multi-step pedal disposed between the two front leg tubes, the side edges of the multi-step pedal being hinged to a pull rod, and the herringbone folding ladder further comprising two symmetrically arranged rear leg tube connecting rods, the ends of the rear leg tube connecting rods being hinged to the rear leg tubes and a pedal, respectively. The present invention, through the coordination of the pull rod, the pedal, and the rear leg tube connecting rod, can drive the rear leg tubes and the pedal to flexibly fold. At the same time, because one end of the rear leg tube connecting rod is hinged to the linked pedal, and the pedal is stronger than the pull rod, compared to the prior art, it can provide better support for the deployment of the rear leg tubes, and the linked pedal is not easily deformed, having higher durability and reliability, and having industrial applicability.

Claims

1. A linked hinged herringbone folding ladder, comprising two ladder frames disposed at their upper ends against each other, the ladder frames having a front leg tube and a rear leg tube, the front leg tube and the rear leg tube forming a herringbone opening and closing structure, a plurality of steps are disposed between the two front leg tubes, the sides of the plurality of steps are hinged to a pull rod, characterized in that: It also includes two symmetrically arranged rear leg tube connecting rods, the two ends of which are respectively hinged to the rear leg tube and a pedal, and the rear end of the pedal is obliquely supported on the rear leg tube.

2. The herringbone folding ladder according to claim 1, characterized in that: One end of the rear leg tube connecting rod hinged to the pedal is higher than one end of the rear leg tube connecting rod hinged to the rear leg tube.

3. The herringbone folding ladder according to claim 1, characterized in that: The side of the pedal hinged with the rear leg tube connecting rod is hinged with the front leg tube, the pull rod and the rear leg tube connecting rod in sequence from the front leg tube to the rear leg tube.

4. The herringbone folding ladder according to claim 1, characterized in that: The side rear section of the pedal hinged with the rear leg tube connecting rod extends outwardly by a first length, and the pedal and the rear leg tube connecting rod are hinged to the side rear section.

5. The herringbone folding ladder according to claim 4, characterized in that: The side front section of the pedal extends outwardly to a second length, the pedal and the front leg tube are hinged to the side front section, and the second length is greater than the first length.

6. The herringbone folding ladder according to claim 1, characterized in that: A support rod is connected between the two rear leg tubes, and the bottom of the uppermost step of the pedal abuts against the support rod; 7. The herringbone folding ladder according to claim 6, characterized in that: A lock is provided at the bottom of the uppermost pedal, and the lock is buckled with the support rod when the pedal is opened.

8. The herringbone folding ladder according to claim 1, characterized in that: The length of the pedal at the uppermost level is greater than or equal to that of the other pedals.

9. The herringbone folding ladder according to claim 6, characterized in that: The orthographic projection of each pedal from top to bottom partially covers the pedal of the next level.

10. The herringbone folding ladder according to claim 1, characterized in that: The side cover of the pedal is provided with a protective cover.

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