A kind of differential speed formula fall arrestor fatigue testing machine

Abstract

A kind of speed difference formula fall arrestor fatigue testing machine, belong to self-locking device test technical field.It includes main frame (5), the speed difference formula fall arrestor (1) to be measured is hung in main frame (5), in main frame (5) it is set with for pulling speed difference formula fall arrestor (1) release weight, in main frame (5) it is also provided with for driving weight to ascend lifting frame (14), lifting frame (14) surface is provided with for adsorbing or releasing release mechanism of weight, it is characterized by: in main frame it is provided with damping mechanism, damping mechanism includes fixed part and movable part, wherein fixed part is arranged on the lifting path of weight, movable part is fixed with weight.In the speed difference formula fall arrestor fatigue testing machine of the present application, by setting damping mechanism, can provide damping for the descent process of weight, while meeting the slow release of speed difference formula fall arrestor, avoid speed difference formula fall arrestor brake, more conducive to speed difference formula fall arrestor complete fatigue test.

Description

Technical Field

[0001] A fatigue testing machine for speed-difference fall arresters belongs to the field of self-locking device testing technology. Background Technology

[0002] A speed-differential fall arrestor is a safety device that utilizes the principle of speed difference. When the falling speed exceeds a set value, the internal locking mechanism quickly activates to brake the falling object, thus rapidly locking it within a limited distance. Its basic operation involves: slowly applying a downward pull to the hook of the speed-differential fall arrestor, which slowly pulls out the steel cable connected to the hook; and then, in an extreme situation, slowly applying a downward pull to the hook triggers the braking force, causing the fall arrestor to rapidly brake and lock the falling object within a limited distance, similar to the mechanism of a seatbelt in a car. To ensure the reliability of the speed-differential fall arrestor, its performance needs to be tested.

[0003] In existing testing devices for speed-differential fall arresters, the common practice is to test the braking performance of the fall arrester. This involves applying a pulling force to the speed-differential fall arrester for a short period of time to trigger its braking performance, and then evaluating the performance of the speed-differential brake by measuring the braking distance. Examples of such technical solutions include: Chinese invention patent application number 201110189045.4, filed on July 6, 2011, entitled "Quick-Check Type Fall Arrester Self-Locking Reliability Performance Testing Machine"; Chinese invention patent application number 202210151481.0, filed on February 17, 2022, entitled "A Fall Arrester Braking Performance Testing Device and Method"; and Chinese utility model patent application number 202322494354.3, filed on September 14, 2023, entitled "A Fall Arrester Test Bench".

[0004] However, according to the relevant provisions of the "Technical Requirements for Fatigue Testing Devices for Differential Fall Arresters" (Standard No. DL / T 1435-2015), before conducting braking performance tests on differential fall arresters, fatigue tests must be conducted. This involves applying a certain amount of tension to the differential fall arrester multiple times (at least 1000 times) at a certain test height, ensuring that the steel cable inside the differential fall arrester is slowly pulled out without triggering its braking action until the differential fall arrester touches the bottom. After completing the set number of fatigue tests, other forms of mechanical tests (such as braking performance tests) are then conducted on the differential fall arrester to evaluate its reliability. In the prior art, a Chinese invention patent with application number 201210070578.5, application date March 16, 2012, and patent name "Fatigue Testing Instrument for Motion Repetitive Mechanism of Speed ​​Difference Controller" describes a technical solution. In this technical solution, the counting of the number of tests is achieved by counting the number of rotations of the guide wheel using a code disk, which has a deviation in counting accuracy.

[0005] The technical solution described in the aforementioned Chinese invention patent, application number 201110189045.4, filed on July 6, 2011, and entitled "Self-locking Reliability Performance Testing Machine for Differential Fall Arrestors," can theoretically conduct fatigue tests on differential fall arrestors. However, when using this solution to conduct fatigue tests on differential fall arrestors, it was found that the test results could not fully reflect the actual fatigue performance of the differential fall arrestor and would further affect the results of subsequent mechanical tests. The reason is that although this technical solution can count the number of times the differential fall arrestor hits the bottom, its essence is still to test the braking performance of the differential fall arrestor. Therefore, when using this technical solution for testing, after the weight is released, the weight is in a state of disordered falling, which easily triggers the braking of the differential fall arrestor. Even if the braking of the differential fall arrestor is not triggered, it is difficult to guarantee the consistency of the slow descent of the differential fall arrestor each time, thus failing to meet the fatigue test requirements of the differential fall arrestor. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a fatigue testing machine for a speed-differential fall arrester that can provide damping for the descent of the weight by setting a damping mechanism, so as to meet the slow release of the speed-differential fall arrester while avoiding braking of the speed-differential fall arrester, and is more conducive to the speed-differential fall arrester completing the fatigue test.

[0007] The technical solution adopted by this utility model to solve its technical problem is as follows: The fatigue testing machine for the speed difference fall arrestor includes a main frame, the speed difference fall arrestor to be tested is hung in the main frame, a weight for pulling the speed difference fall arrestor to release is provided in the main frame, a lifting frame for driving the weight to rise is also provided in the main frame, and a release mechanism for adsorbing or releasing the weight is provided on the surface of the lifting frame. The feature is that a damping mechanism is provided in the main frame, the damping mechanism includes a fixed part and a movable part, wherein the fixed part is arranged on the lifting path of the weight, and the movable part is fixed to the weight.

[0008] Preferably, in the damping mechanism, the fixed part is a damping guide rail arranged on the lifting path of the weight, and the movable part is a damper that is slidably connected to the damping guide rail, with the damper fixed to the bottom of the weight.

[0009] Preferably, the weight includes a weight rack, a weight ring on the surface of the weight rack for connection with a speed difference fall arrester, a weight pan on the surface of the weight ring, a damping guide rail passing through the weight rack, and a damper fixed to the bottom of the weight rack.

[0010] Preferably, a counting sensor for detecting the weight is provided at the bottom of the weight lifting path.

[0011] Preferably, a slide rail is provided inside the main frame, the lifting frame is slidably connected to the slide rail, and a drive mechanism for driving the lifting frame to rise and fall is also provided on the side of the slide rail.

[0012] Preferably, the drive mechanism includes a synchronous belt mechanism arranged parallel to the slide rail, the lifting frame is fixed to the synchronous belt in the synchronous belt mechanism, and the motor shaft of the drive motor is connected to the drive pulley in the synchronous belt mechanism.

[0013] Preferably, the lifting frame is located above the weight rack and is staggered with the weight rack. A position sensor is provided at the bottom of the lifting frame to detect the weight rack and to trigger the release mechanism.

[0014] Preferably, the release mechanism is an electromagnet located at the bottom of the lifting frame.

[0015] Compared with the prior art, the beneficial effects of this utility model are: In the fatigue testing machine for the differential fall arrester of this application, by setting a damping mechanism, damping can be provided for the descent process of the weight, so as to meet the slow release of the differential fall arrester and avoid the braking of the differential fall arrester, which is more conducive to the completion of the fatigue test of the differential fall arrester.

[0016] Several weight pans are attached to the side of the weight ring rod to allow for the replacement of weights of different masses. Attached Figure Description

[0017] Figure 1 This is an isometric drawing of a fatigue testing machine for a speed-difference type fall arrestor.

[0018] Figure 2 This is a front view of the fatigue testing machine for speed difference type fall arrestors.

[0019] Figure 3 for Figure 2 The diagram after the front cover is omitted.

[0020] Figure 4 for Figure 3 Sectional view along the AA direction.

[0021] Figure 5 for Figure 3 Enlarged view of point A in the middle.

[0022] Figure 6 for Figure 3 Enlarged view of section B in the middle.

[0023] The components include: 1. Differential fall arrestor; 2. Test hanging ring; 3. Test hole; 4. Test platform; 5. Main frame; 6. Front end cover; 7. Damping guide rail; 8. Slide rail; 9. Buffer; 10. Conveyor belt; 11. Driven wheel; 12. Weight hanging ring; 13. Weight pan; 14. Lifting frame; 15. Electromagnet; 16. Weight rack; 17. Damper; 18. Position sensor; 19. Drive motor; 20. Counting sensor. Detailed Implementation

[0024] Figures 1-6 This is the preferred embodiment of the present invention, which is described below in conjunction with the appendix. Figures 1-6 The present invention will be further described below.

[0025] like Figures 1-4 As shown, a fatigue testing machine for a speed-difference fall arrestor (hereinafter referred to as the testing machine) includes a main frame 5. A test platform 4 is horizontally arranged in the middle of the main frame 5. The test platform 4 divides the inner cavity of the main frame 5 into upper and lower test chambers, and a front cover 6 is provided at the front port of the lower test chamber. The front port of the upper test chamber is either open or closed by a transparent panel. A test hanging ring 2 is provided at the top of the upper test chamber, and the speed-difference fall arrestor 1 to be tested is hung on the test hanging ring 2.

[0026] Combination Figures 3-6 On the rear end face of the lower test chamber within the main frame 5, two slide rails 8 are arranged side by side. A lifting frame 14 is located on the front side of the two slide rails 8, and a slider is installed on the rear end face of the lifting frame 14. The lifting frame 14 is slidably connected to the slide rails 8 via the slider. A drive mechanism is provided between the two slide rails 8, which drives the lifting frame 14 to move up and down along the slide rails 8 within the lower test chamber.

[0027] The drive mechanism includes a drive motor 19 mounted on the upper part of the slide rails 8. A drive wheel and a driven wheel 11 are respectively mounted at the upper and lower parts between the two slide rails 8. The drive wheel and the driven wheel 11 are connected by a conveyor belt 10, preferably a synchronous belt. The conveyor belt 10 is fixed to the rear end face of the lifting frame 14, and the motor shaft of the drive motor 19 is coaxially fixed with the drive wheel. Therefore, the drive wheel, the driven wheel 11, and the conveyor belt 10 form a synchronous belt mechanism that drives the lifting frame 14 to rise and fall. The drive motor 19 drives the synchronous belt mechanism to achieve the lifting of the lifting frame 14.

[0028] A damping mechanism is provided on the front side of the lower test chamber. The damping mechanism includes a damping guide rail 7 vertically arranged inside the lower test chamber and a damper 17 mounted on the surface of the damping guide rail 7. A weight rack 16 is fitted outside the damping guide rail 7. The weight rack 16 moves up and down along the damping guide rail 7, and the damper 17 is fixed to the bottom of the weight rack 16. When the weight rack 16 rises and falls along the damping guide rail 7, the damping guide rail 7 and the damper 17 work together to provide damping force for each rise and fall of the weight rack 16, so as to achieve slow and constant speed rise and fall of the weight rack 16. The connection method and working principle of the damping guide rail 7 and the damper 17 are common knowledge in the field. For example, the technical solution described in Chinese Utility Model Patent Application No. 202421921828.6, filed on August 9, 2024, entitled "A Linear Guide Rail with Damping and Vibration Resistance Function" will not be repeated here.

[0029] The weight rack 16 extends rearward to the lower part of the lifting frame 14. Electromagnets 15 for attracting the weight rack 16 are provided on both sides of the lower part of the lifting frame 14. The control box of this testing machine is provided on the side wall of the lower test chamber. The controller and drive circuit of this testing machine (such as the drive circuit of the motor and the drive circuit of the electromagnet 15) are provided in the control box.

[0030] A position sensor 18 is provided on one side of the bottom of the lifting frame 14. The position sensor 18 is implemented using an inductive proximity switch known in the art. The signal output terminal of the position sensor 18 is connected to the signal input terminal of the controller. The position sensor 18 is used to detect the position of the weight rack 16. When the weight rack 16 approaches the position sensor 18 and triggers the position sensor 18, the position sensor 18 sends a signal to the controller. The controller controls the coil of the electromagnet 15 to be energized, so that the electromagnet 15 has a magnetic force to attract the weight rack 16.

[0031] A weight ring 12 is provided on the surface of the weight rack 16. The weight ring 12 includes a rod and a ring at the top of the rod. The rod is vertically fixed to the surface of the weight rack 16, and multiple weight pans 13 are clamped to the outside of the rod. A test hole 3 is provided on the surface of the test bench 4, and the ring of the weight ring 12 faces upward directly towards the test hole 3.

[0032] The specific experimental procedure and experimental principle are as follows: In the initial state, the lifting frame 14 is located at the top of the slide rail 8. At this time, the weight holder 16 is attracted to the lower part of the lifting frame 14 under the magnetic force of the electromagnet 15. The top hook of the speed difference fall arrestor 1 to be tested is hung on the test hanging ring 2, and its bottom hook is pulled. As the steel cable inside the speed difference fall arrestor 1 is continuously pulled out, the bottom hook passes through the test hole 3 and is connected to the weight hanging ring 12.

[0033] After the test begins, the controller de-energizes the coil of electromagnet 15. After electromagnet 15 loses its magnetic attraction to weight rack 16, weight rack 16 begins to fall. Since damper 17 and damping guide rail 7 provide damping force to weight rack 16, the braking of speed difference type fall arrestor 1 will not be triggered during the slow pull-down process of weight rack 16.

[0034] A buffer 9 is installed at the bottom of the lower test chamber. The buffer 9 can be hydraulically or spring-loaded and is located between the slide rail 8 and the damping guide rail 7. A counting sensor 20 for detecting the weight holder 16 is installed on the side of the buffer 9. The counting sensor 20 can also be implemented using the same inductive proximity switch as the position sensor 18. When the weight holder 16 touches the bottom and falls onto the surface of the buffer 9, it simultaneously triggers the counting sensor 20. After being triggered, the counting sensor 20 sends a signal to the main controller. The main controller counts the weights and simultaneously controls the drive motor 19 to work.

[0035] After the drive motor 19 starts working, it rotates in the forward direction and drives the lifting frame 14 to descend along the slide rail 8 through the synchronous belt mechanism. The drive motor 19 is preferably a servo motor. Since the height of the slide rail 8 is a fixed value, the specific position of the lifting frame 14 and the slide rail 8 can be obtained by controlling the pulse of the drive motor 19. Alternatively, the position of the lifting frame 14 can be controlled by setting limit switches (such as travel switches) at the top and bottom of the slide rail 8.

[0036] As the lifting frame 14 descends, the distance between the lifting frame 14 and the weight rack 16 gradually decreases. When the weight rack 16 approaches the position sensor 18 and triggers the position sensor 18, the position sensor 18 sends a signal to the controller. The controller then controls the coil of the electromagnet 15 to be energized, so that the electromagnet 15 has the magnetic force to attract the weight rack 16, and the lifting frame 14 and the weight rack 16 are attracted together.

[0037] Then the main controller controls the drive motor 19 to rotate in the opposite direction, which drives the lifting frame 14 and the weight frame 16 to rise synchronously through the synchronous belt mechanism. When the lifting frame 14 rises to the top of the slide rail 8, the main controller controls the drive motor 19 to stop rotating, and the test is completed. This process is repeated until the preset number of tests is reached.

[0038] 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 fatigue testing machine for a speed-difference fall arrester, comprising a main frame (5), wherein a speed-difference fall arrester (1) to be tested is suspended inside the main frame (5), and a weight for pulling the speed-difference fall arrester (1) is provided within the main frame (5) in a height-adjustable manner, and a lifting frame (14) for driving the weight to rise is also provided within the main frame (5), and a release mechanism for adsorbing or releasing the weight is provided on the surface of the lifting frame (14), characterized in that: A damping mechanism is provided inside the main frame (5). The damping mechanism includes a fixed part and a movable part. The fixed part is arranged on the lifting path of the weight, and the movable part is fixed to the weight.

2. The fatigue testing machine for speed-difference fall arresters according to claim 1, characterized in that: In the damping mechanism, the fixed part is a damping guide rail (7) arranged on the lifting path of the weight, and the movable part is a damper (17) that is slidably connected to the damping guide rail (7). The damper (17) is fixed to the bottom of the weight.

3. The fatigue testing machine for speed-difference fall arresters according to claim 2, characterized in that: The weights include a weight rack (16), a weight ring (12) for connecting to the speed difference fall arrester (1) is provided on the surface of the weight rack (16), a weight pan (13) is provided on the surface of the weight ring (12), a damping guide rail (7) passes through the weight rack (16), and a damper (17) is fixed to the bottom of the weight rack (16).

4. The fatigue testing machine for speed-difference type fall arresters according to any one of claims 1 to 3, characterized in that: A counting sensor (20) for detecting the weight is installed at the bottom of the weight lifting path.

5. The fatigue testing machine for speed-difference fall arresters according to claim 1, characterized in that: A slide rail (8) is provided inside the main frame (5), and the lifting frame (14) is slidably connected to the slide rail (8). A drive mechanism for driving the lifting frame (14) to rise and fall is also provided on the side of the slide rail (8).

6. The fatigue testing machine for speed-difference fall arresters according to claim 5, characterized in that: The drive mechanism includes a synchronous belt mechanism arranged parallel to the slide rail (8), the lifting frame (14) is fixed to the synchronous belt in the synchronous belt mechanism, and the motor shaft of the drive motor (19) is connected to the drive wheel in the synchronous belt mechanism.

7. The fatigue testing machine for speed-difference type fall arresters according to claim 3, characterized in that: The lifting frame (14) is located on the upper part of the weight rack (16) and is staggered with the weight rack (16). A position sensor (18) is provided at the bottom of the lifting frame (14) for detecting the weight rack (16) and triggering the release mechanism.

8. The fatigue testing machine for speed-difference fall arresters according to claim 1 or 7, characterized in that: The release mechanism is an electromagnet (15) located at the bottom of the lifting frame (14).

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