A test device for the stability of a ladder

Abstract

A kind of test device of stability of herringbone ladder belongs to hard ladder test technical field.It includes main frame (2) and the herringbone ladder (29) to be measured fixed in the side of main frame (2), it is characterized by being provided with the side pull mechanism (5) for the horizontal tension of the herringbone ladder (29) to be measured and the static load mechanism (7) for the vertical gravity of the herringbone ladder (29) to be measured, the side pull mechanism (5) and static load mechanism (7) are simultaneously connected with the herringbone ladder (29) to be measured;Side pull mechanism (5) is set in the side of main frame (2) and can be lifted.In the herringbone ladder stability test device of the present application, by setting side pull mechanism and static load mechanism, respectively, to the herringbone ladder to be measured horizontal tension and vertical gravity, in order to test the stability of the herringbone ladder to be measured.Side pull mechanism is set in the side of main frame and can be lifted, in order to be suitable for the test of herringbone ladder of different height.

Description

Technical Field

[0001] A test device for the stability of an A-frame ladder, belonging to the field of rigid ladder testing technology. Background Technology

[0002] A-frame ladders are commonly used auxiliary equipment in live-line work. Therefore, the stability of A-frame ladders during use is an important indicator of their safety performance and a crucial guarantee for the personal safety of workers. The national standard GB / T17620-2008 "Insulated Rigid Ladders for Live-line Work" specifies the test standards for the stability of A-frame ladders. In the prior art, some of the test schemes for ladders are performance tests for straight ladders. These schemes are difficult to apply to the testing of A-frame ladders. For example, the technical solutions described in Chinese utility model patent application number 201921927826.7, application date November 8, 2019, entitled "A Static Load Testing Machine for Ladders"; the technical solutions described in Chinese invention patent application number 202310869230.0, application date July 17, 2023, entitled "Static Load Testing Method and Device for Ladders"; and the technical solutions described in Chinese utility model patent application number 202220726386.4, application date March 31, 2022, entitled "A Comprehensive Tester for Two-Station Ladders".

[0003] In the prior art, there are also some solutions for testing A-frame ladders, such as the technical solution described in the Chinese utility model patent with application number 202421379912.X, application date June 17, 2024, entitled "A Tension Strength Testing Device for A-frame Ladder"; the technical solution described in the Chinese invention patent with application number 202111474897.8, application date December 6, 2021, entitled "A Static Load Tensile Test Device and Method for Rigid Ladders"; and the technical solution described in the Chinese invention patent with application number 202210051167.5, application date January 17, 2022, entitled "A Testing Device for Safety Tools".

[0004] However, the aforementioned test schemes for A-frame ladders are generally for static load tests, and cannot realize the actual stability test of A-frame ladders. Therefore, designing a technical solution for testing A-frame ladders has become an urgent problem to be solved in this field. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a test device for the stability of an A-frame ladder by setting a side tension mechanism and a static load mechanism to apply horizontal tension and vertical gravity to the A-frame ladder under test, so as to test the stability of the A-frame ladder under test.

[0006] The technical solution adopted by this utility model to solve its technical problem is: the test device for the stability of the A-frame ladder includes a main frame and the A-frame ladder to be tested fixed on the side of the main frame. The device is characterized by: a side-pull mechanism for applying horizontal tension to the A-frame ladder to be tested and a static load mechanism for applying vertical gravity to the A-frame ladder to be tested. The side-pull mechanism and the static load mechanism are connected to the A-frame ladder to be tested. The side-pull mechanism is set on the side of the main frame in a height-adjustable manner.

[0007] Preferably, the side-pull mechanism includes a side-pull bracket, a horizontal tension component is provided on the upper surface of the side-pull bracket, a side-pull clamp is connected to the end of the horizontal tension component, the side-pull clamp is fixedly connected to the A-frame ladder to be tested, and a lifting drive mechanism is also provided at the lower part of the side-pull bracket.

[0008] Preferably, the horizontal tension assembly includes a linear module, in which a tension sensor is connected to a slide, and the other end of the tension sensor is connected to a side tension rod, which is connected to a side tension clamp.

[0009] Preferably, the side-pull clamp includes an upper side-pull clamp and a lower side-pull clamp that are arranged opposite to each other and used to clamp the A-frame ladder to be tested, wherein the upper side-pull clamp is connected to the horizontal tension assembly.

[0010] Preferably, the lifting drive mechanism includes a lifting motor fixed to the lower part of the side support bracket, a gear fixed at the motor shaft of the lifting motor, and a rack meshing with the gear on the side of the main frame.

[0011] Preferably, a slider is provided on the end face of the side pull bracket facing the main frame, and a slide rail is provided on the surface of the main frame to slide and connect with the slider.

[0012] Preferably, the static load mechanism includes a static load clamp and a weight pan attached to the bottom of the static load clamp.

[0013] Preferably, the static load clamp includes an upper static load clamp and a lower static load clamp arranged opposite to each other for clamping the A-frame ladder to be tested. A suspension rod is connected to the lower part of the lower static load clamp by a steel cable, and a weight pan is installed on the suspension rod.

[0014] Compared with the prior art, the beneficial effects of this utility model are: In the test apparatus for the stability of the A-frame ladder in this application, a side tension mechanism and a static load mechanism are set up to apply horizontal tension and vertical gravity to the A-frame ladder under test, respectively, so as to test the stability of the A-frame ladder under test.

[0015] The side-pull mechanism is mounted on the side of the main frame in a height-adjustable manner to accommodate tests of A-frame ladders of different heights.

[0016] The weight pan is detachably mounted at the bottom of the suspension rod to allow for adjustment of the gravity applied to the A-frame ladder under test.

[0017] The end of the side-pull clamp is bent vertically downward to form a side plate. The side plate is placed over the outside of the hinge plate in the middle of the A-frame ladder under test. The connection angle between the side-pull clamp and the A-frame ladder under test is confirmed to ensure that the fixed angle between the side-pull clamp and the A-frame ladder under test is right-angled, thus ensuring test accuracy. Attached Figure Description

[0018] Figure 1 This is an isometric view of the test setup for the stability of the A-frame ladder.

[0019] Figure 2 This is a front view of the test setup for the stability of the A-frame ladder.

[0020] Figure 3 This is an isometric view of the side tension mechanism of the test device for the stability of the A-frame ladder.

[0021] Figure 4 This is a front view of the side tension mechanism of the test device for the stability of the A-frame ladder.

[0022] Figure 5 for Figure 4 Top view.

[0023] Figure 6 This is an isometric view of the side tension clamp of the test device for the stability of the A-frame ladder.

[0024] Figure 7 This is an isometric view of the side tension clamp of the test device for the stability of the A-frame ladder.

[0025] Figure 8 This is an isometric view of the static load mechanism of the test device for the stability of the A-frame ladder.

[0026] Figure 9 This is a schematic diagram of the test setup for the stability of the A-frame ladder.

[0027] The components include: 1. Control box; 2. Main frame; 3. Slide rail; 4. Rack; 5. Side pull mechanism; 6. Side pull clamp; 7. Static load mechanism; 8. Slider; 9. Vertical plate; 10. Lifting motor; 11. Side pull plate; 12. Side pull rod; 13. Guide wheel frame; 14. Guide wheel; 15. Tension sensor; 16. Linear module; 17. Gear; 18. Side plate; 19. Side pull locking hole; 20. Side pull lower clamp; 21. Side pull upper clamp; 22. Static load upper clamp; 23. Fixing plate; 24. Static load locking hole; 25. Static load lower clamp; 26. Steel cable; 27. Hanging rod; 28. Weight pan; 29. ​​A-frame ladder to be tested. Detailed Implementation

[0028] Figures 1-9 This is the preferred embodiment of the present invention, which is described below in conjunction with the appendix. Figures 1-9 The present invention will be further described below.

[0029] like Figures 1-2 As shown, a test device for the stability of an A-frame ladder includes a vertically arranged main frame 2. Two parallel slide rails 3 are vertically arranged side-by-side on one side of the main frame 2. A rack 4 is also arranged parallel to the side of one of the slide rails 3. A side-pulling mechanism 5, slidably connected to the two slide rails 3, is provided on the side of the main frame 2. A gear 17 in the side-pulling mechanism 5 (see...) Figure 5 At the same time, it meshes with the rack 4. When the gear 17 rotates, it drives the side pull mechanism 5 to rise and fall vertically along the slide rail 3.

[0030] The side-pull mechanism 5 connects to the A-frame ladder 29 to be tested via the side-pull clamp 6 (see...). Figure 9 The two sides are connected, and a static load mechanism 7 is also provided on the side of the main frame 2. During the test, the side pull mechanism 5 and the static load mechanism 7 are connected to the A-frame ladder 29 to be tested. While the static load mechanism 7 applies a downward gravity to the A-frame ladder 29 to be tested, the side pull mechanism 5 applies a horizontal pull force to the A-frame ladder 29 to be tested, so as to test the stability of the A-frame ladder 29 to be tested.

[0031] like Figures 3-5 As shown, the side-pull mechanism 5 includes a side-pull bracket, which is fixed by a side-pull plate 11 and a vertical plate 9. The side-pull plate 11 is horizontally arranged, and the vertical plate 9 is vertically fixed to the end of the side-pull plate 11. On both sides of the vertical plate 9 facing the end face of the main frame 2, a set of sliders 8 are respectively arranged, and the sliders 8 on both sides are slidably connected to two slide rails 3 respectively.

[0032] A lifting motor 10 is fixed at the bottom of the upright plate 9. The motor shaft of the lifting motor 10 passes through the upright plate 9 and extends to the side of the slider 8. A gear 17 that meshes with the rack 4 is coaxially fixed at the motor shaft. A linear module 16 is provided on the front side of the upper surface of the side pull plate 11. The linear module 16 is arranged along the length direction of the side pull plate 11.

[0033] A tension sensor 15 is connected to one end of the slide in the linear module 16, and a side pull rod 12 is connected to the other end of the tension sensor 15. The other end of the side pull rod 12 is connected to the side pull clamp 6. A guide wheel frame 13 is also provided on the surface of the side pull plate 11, and the guide wheel frame 13 is fixed at the far end of the slide's movement path in the linear module 16. Two guide wheels 14 are arranged opposite each other on the top of the guide wheel frame 13, and the side pull rod 12 passes through the two guide wheels 14 and extends to the side pull clamp 6.

[0034] A control box 1 is also installed at the bottom of the main frame 2. The control box 1 contains a main controller, which controls the lifting motor 10 and the linear module 16. At the same time, the signal output terminal of the tension sensor 15 is connected to the signal input terminal of the main controller, and the tension applied to the A-frame ladder 29 under test is obtained through the main controller.

[0035] like Figures 6-7 As shown, the side-pull clamp 6 includes a side-pull upper clamp 21 and a side-pull lower clamp 20 arranged opposite to each other. Side-pull locking holes 19 are respectively opened at the four corners of the side-pull upper clamp 21 and the side-pull lower clamp 20. The side-pull locking holes 19 at corresponding positions of the side-pull upper clamp 21 and the side-pull lower clamp 20 are arranged in multiple groups, and a locking bolt (not shown in the figure) is installed in each group.

[0036] When the side-pull clamp 6 is clamped to the A-frame ladder 29 under test, the side-pull clamp 6 is fixed at the middle hinge plate of the two straight ladders in the A-frame ladder 29 under test. At this time, the upper side-pull clamp 21 and the lower side-pull clamp 20 are located on the upper and lower sides of the hinge plate in the A-frame ladder 29 under test, respectively. When the locking bolts at the four corners are tightened, the upper side-pull clamp 21 and the lower side-pull clamp 20 clamp the hinge plate in the middle of the A-frame ladder 29 under test.

[0037] An extension plate extends horizontally along one edge of the side-pull clamp 21, and a side plate 18 is formed by bending vertically downward at the end of the extension plate. When the side-pull clamp 6 is fixed to the A-frame ladder 29 under test, the side plate 18 covers the outside of the hinge plate in the middle of the A-frame ladder 29 under test. The connection angle between the side-pull clamp 6 and the A-frame ladder 29 under test is confirmed to ensure that the fixing angle between the side-pull clamp 6 and the A-frame ladder 29 under test is right-angled, thus ensuring test accuracy.

[0038] At the edge of the side pull plate 21 facing the side pull mechanism 5, a fixed plate 23 is formed by bending it vertically downward. A fixed hole is provided in the middle of the fixed plate 23, and a hook (not shown in the figure) is installed in the fixed hole. The side pull rod 12 is connected through the hook in the middle of the fixed plate 23.

[0039] like Figure 8 As shown, the static load mechanism 7 includes a static load clamp, which includes a static load upper clamping plate 22 and a static load lower clamping plate 25 that are arranged opposite to each other. Static load locking holes 24 are respectively opened at the four corners of the static load upper clamping plate 22 and the static load lower clamping plate 25. The static load locking holes 24 at corresponding positions of the static load upper clamping plate 22 and the static load lower clamping plate 25 are arranged in multiple groups, and a locking bolt is installed in each group.

[0040] When the static load clamp is used to clamp the A-frame ladder 29 to be tested, the static load clamp is fixed at the cross brace of one side of the straight ladder of the A-frame ladder 29 to be tested. At this time, the upper static load clamp 22 and the lower static load clamp 25 are located on the upper and lower sides of the cross brace, respectively. When the locking bolts at the four corners are tightened, the upper static load clamp 22 and the lower static load clamp 25 will clamp the cross brace.

[0041] A steel cable 26 is attached to the bottom of the clamping plate 25 under static load. A suspension rod 27 is connected to the bottom of the steel cable 26. Multiple weight pans 28 are mounted on the outside of the suspension rod 27. By changing the number of weight pans 28, the gravity applied to the cross brace of the A-frame ladder 29 to be tested is adjusted.

[0042] The specific working process and working principle are as follows: like Figure 9 As shown, the A-frame ladder 29 to be tested is placed on the ground and put into operation. At this time, the angle between the straight ladders on both sides of the A-frame ladder 29 and the ground is 75°±5°. The lifting motor 10 is controlled to work, so that the side pull mechanism 5 is flush with the hinge plate at the top of the A-frame ladder 29. The side pull clamp 6 described above is connected to and clamped to the hinge plate in the middle of the A-frame ladder 29. At the same time, the static load clamp in the static load mechanism 7 is connected to and clamped to the second cross brace at the top of the straight ladder facing the main frame 2. The side pull clamp 6 is then hooked to the side pull rod 12.

[0043] At this time, the static load mechanism 7 is vertically downward. By adjusting the number of weight pans 28, a static load of 1000N is applied to the cross brace connected to the static load fixture. Then, the slide in the linear module 16 is controlled to move, and a horizontal pulling force is applied to the A-frame ladder 29 under test through the side pull rod 12. The horizontal pulling force value is gradually increased to 120N through the tension sensor 15. At this time, the stability of the A-frame ladder 29 under test is judged by whether there is relative movement between the A-frame ladder 29 under test and the ground.

[0044] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from its technical solution shall still fall within the protection scope of this utility model.

Claims

1. A test apparatus for the stability of an A-frame ladder, comprising a main frame (2) and an A-frame ladder (29) to be tested fixed to the side of the main frame (2), characterized in that: The system is equipped with a side-pull mechanism (5) for applying horizontal tension to the A-frame ladder (29) under test and a static load mechanism (7) for applying vertical gravity to the A-frame ladder (29) under test. The side-pull mechanism (5) and the static load mechanism (7) are connected to the A-frame ladder (29) under test. The side-pull mechanism (5) is installed on the side of the main frame (2) in a height-adjustable manner.

2. The testing apparatus for the stability of the A-frame ladder according to claim 1, characterized in that: The side-pull mechanism (5) includes a side-pull bracket, a horizontal tension component is provided on the upper surface of the side-pull bracket, a side-pull clamp (6) is connected to the end of the horizontal tension component, the side-pull clamp (6) is fixedly connected to the A-frame ladder (29) to be tested, and a lifting drive mechanism is also provided at the lower part of the side-pull bracket.

3. The testing apparatus for the stability of the A-frame ladder according to claim 2, characterized in that: The horizontal tension assembly includes a linear module (16), a tension sensor (15) is connected to the slide in the linear module (16), and a side pull rod (12) is connected to the other end of the tension sensor (15). The side pull rod (12) is connected to the side pull clamp (6).

4. The testing apparatus for the stability of an A-frame ladder according to claim 2 or 3, characterized in that: The side-pull clamp (6) includes an upper side-pull clamp (21) and a lower side-pull clamp (20) that are arranged opposite to each other and used to clamp the A-frame ladder (29) to be tested. The upper side-pull clamp (21) is connected to the horizontal tension assembly.

5. The testing apparatus for the stability of the A-frame ladder according to claim 2, characterized in that: The lifting drive mechanism includes a lifting motor (10) fixed to the lower part of the side support bracket, a gear (17) fixed at the motor shaft of the lifting motor (10), and a rack (4) that meshes with the gear (17) on the side of the main frame (2).

6. The testing apparatus for the stability of the A-frame ladder according to claim 2, characterized in that: A slider (8) is provided on the end face of the side support facing the main frame (2), and a slide rail (3) is provided on the surface of the main frame (2) to slide and connect with the slider (8).

7. The testing apparatus for the stability of an A-frame ladder according to claim 1, characterized in that: The static load mechanism (7) includes a static load clamp and a weight pan (28) attached to the bottom of the static load clamp.

8. The testing apparatus for the stability of an A-frame ladder according to claim 7, characterized in that: The static load clamp includes a static load upper clamping plate (22) and a static load lower clamping plate (25) that are arranged opposite to each other and used to clamp the A-frame ladder (29) to be tested. A suspension rod (27) is connected to the lower part of the static load lower clamping plate (25) by a steel cable (26), and a weight pan (28) is installed on the suspension rod (27).

Images