A falling object protection structure safety performance test bench

Abstract

This invention provides a test bench for the safety performance of falling object protection structures (FOPS), belonging to the technical field of FOPS testing. It includes a falling hammer self-locking system, a falling hammer lifting system, and a specimen fixing system. The falling hammer self-locking system comprises a coaxially arranged rotating ring, a ring fixing rod, a release cover, a mounting base, an electromagnet, a falling hammer, a release shaft, a push rod, and a push rod drive unit. The falling hammer lifting system is connected to the rotating ring and is used to lift the falling hammer self-locking system to a preset height. The specimen fixing system is installed below the falling hammer to fix the specimen. The above-mentioned test bench for the safety performance of falling object protection structures fully ensures the personal safety of experimental operators and the safe implementation of falling object protection structure (FOPS) tests.

Description

Technical Field

[0001] This invention belongs to the technical field of falling object protection structure testing, and specifically discloses a falling object protection structure safety performance test bench. Background Technology

[0002] When rubber-tired transport equipment is operating in underground roadways, insecure roof support or deformation of the roof and sidewalls can cause coal and rock mass to detach, leading to deformation and penetration of the vehicle cab and injury to the driver and passengers. Falling Object Protection Structures (FOPS) are crucial protective measures for vehicle cabs and passenger compartments. To prevent such accidents and resulting injuries, the safety performance of the FOPS in the cab or driver's cab and passenger compartment must be ensured according to the vehicle type and function. This invention provides a FOPS safety performance testing bench for this purpose. Summary of the Invention

[0003] The purpose of this invention is to provide a test bench for the safety performance of falling object protection structures (FOPS) so as to achieve safe implementation of falling object protection structure (FOPS) tests.

[0004] The aforementioned test bench for the safety performance of a falling object protection structure includes a falling hammer self-locking system, a falling hammer lifting system, and a specimen fixing system. The falling hammer self-locking system includes a coaxially arranged rotating ring, a ring fixing rod, a release cover, a mounting base, an electromagnet, a falling hammer, a release shaft, a push rod, and a push rod drive unit. The ring fixing rod passes vertically through the top surface of the release cover. The rotating ring and the portion of the ring fixing rod outside the release cover are rotatably connected. The top surface of the mounting base is fixedly connected to the bottom surface of the release cover, and the bottom surface is fixedly connected to the top surface of the electromagnet. The bottom surface of the electromagnet electromagnetically attracts the top surface of the falling hammer. The top surface of the falling hammer has a central blind hole extending axially downwards. The release shaft has a central through hole penetrating the top and bottom surfaces, and the release shaft vertically penetrates the bottom surface of the release cover, the mounting base, and the electromagnet. The magnet has a connecting section located below the electromagnet. This section is inserted into the central blind hole of the drop hammer and has radial holes that connect to the central through hole. Ball bearings are installed in the radial holes. The push rod is inserted into the central through hole of the release shaft. The locking section extends from the bottom upwards at a predetermined distance, with its diameter gradually decreasing from top to bottom. The top surface of the push rod drive unit is connected to the lifting ring fixing rod, and the bottom surface is connected to the top surface of the push rod. This is used to push the push rod downwards to force the locking section to press the ball bearings against the central blind hole of the drop hammer, and to pull the push rod upwards to create a radial gap between the locking section and the release shaft. The drop hammer lifting system is connected to the rotating lifting ring and is used to lift the drop hammer self-locking system to a predetermined height. The specimen fixing system is installed below the drop hammer and is used to fix the specimen.

[0005] Furthermore, the aforementioned test bench for the safety performance of falling object protection structures also includes multiple vertically arranged guide rails; all the guide rails are located above the test specimen and are evenly arranged around the central axis of the falling hammer self-locking system; the release cover and / or mounting base are provided with guide ears corresponding to the guide rails one by one, and each guide ear is provided with a guide hole that is slidably sleeved outside the guide rail.

[0006] Furthermore, the aforementioned test bench for the safety performance of falling object protection structures also includes an interlocking straightening system; the interlocking straightening system includes a mounting frame, a buckle, a buckle drive unit, and a locking tongue; the mounting frame is installed on the bottom surface of the guide rail and has a drop hammer hole penetrating the top and bottom surfaces; the buckle is rotatably connected to the mounting frame, and its center is coaxially arranged with the center of the drop hammer hole and the center of the drop hammer, and the inner wall of the buckle is provided with a roller groove; multiple sets of locking tongues are evenly arranged around the center of the buckle, and each set of locking tongues includes a pull rod, a swing arm, and a track roller; the first end of the pull rod is rotatably connected to the buckle, and the second end is rotatably connected to the first end of the swing arm, and the second end of the swing arm is rotatably mounted with a track roller, which slides along the roller groove; the buckle drive unit is used to drive the buckle to rotate and extend or retract the swing arm.

[0007] Furthermore, the aforementioned test bench for the safety performance of the falling object protection structure also includes a control system; the interlocking straightening system also includes a proximity switch, which is installed on the guide rail and located at the preset start position of the interlocking straightening system. When the falling hammer is detected, the proximity switch transmits a signal to the control system; the electromagnet, the push rod drive unit, and the buckle drive unit are all controlled by the control system.

[0008] Furthermore, the aforementioned test bench for the safety performance of falling object protection structures also includes a deformation measurement system; the deformation measurement system includes a DLV model, a DLV head sensor, a three-dimensional coordinate scanner, and a high-speed camera; the DLV model is installed inside the specimen; the DLV head sensor is implanted in the head of the DLV model to automatically sense the contact or intrusion of foreign objects and transmit the signal to the control system; the three-dimensional coordinate scanner is used to scan the surface shape of the specimen and transmit the signal to the control system; the high-speed camera is used to record the process of the falling hammer impacting the specimen and transmit the signal to the control system.

[0009] Furthermore, the aforementioned test bench for the safety performance of falling object protection structures also includes an energy verification system; the energy verification system includes several photoelectric switches installed on the guide rails; when the photoelectric switches detect the falling hammer, they transmit a signal to the control system; the control system calculates the magnitude of the acceleration based on the distance between the photoelectric switches and the time it takes for the falling hammer to pass through the photoelectric switches, and compares it with the gravitational acceleration at the test site to verify the energy of the falling hammer at different heights.

[0010] Furthermore, the aforementioned test bench for the safety performance of falling object protection structures includes a test bench frame; the test bench frame includes a support frame, an upper protection set above the support frame, a lower support protection set below the support frame, and a specimen fixing platform set on the lower support protection; the specimen fixing system is installed on the specimen fixing platform; the guide rail is connected to the support frame through the fixing frame and is suspended above the specimen.

[0011] Furthermore, the specimen fixing system includes a transition plate and multiple ground spikes; the ground spikes include a threaded cylinder, a threaded rod, and a connecting plate; the bottom surface of the threaded cylinder is fixed to the specimen fixing platform; the threaded rod is threadedly connected to the threaded cylinder, and a connecting plate is installed at the top; the transition plate and the connecting plate of the multiple ground spikes are detachably connected; the specimen is installed on the transition plate.

[0012] Furthermore, the push rod drive unit is a push rod cylinder; the drop hammer lifting system includes a lifting motor, an electric winch, and a wire rope; both the lifting motor and the electric winch are mounted on a fixed frame, and the lifting motor drives the electric winch to rotate; the wire rope is wound on the electric winch, and its end is led out and connected to the rotating lifting ring; the buckle drive unit is a buckle cylinder, and its two ends are connected to the buckle and the mounting frame respectively through pins.

[0013] Furthermore, the support frame is a multi-layer steel frame structure with ladders installed between layers; the upper protection includes a steel frame, protective plates, and lightning protection devices, with the steel frame connected to the support frame and the protective plates laid on the outside of the steel frame; the lower support protection includes a steel frame and protective plates, with the steel frame connected to the support frame and the protective plates laid on the outside of the steel frame; the specimen fixing platform is a cast iron platform with external dimensions of not less than 4000mm×2200mm×2500mm.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The aforementioned test bench for the safety performance of falling object protection structures fully considers the hazards of falling coal and rock masses to drivers and passengers, simulates the free fall motion of falling rock masses to the greatest extent, and has a simple structure, stable operation, high test accuracy, and does not require close-range manual operation, thus fully ensuring the personal safety of experimental operators and the safe implementation of the falling object protection structure (FOPS) test. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1A three-dimensional view of the test bench for the safety performance of falling object protection structures;

[0018] Figure 2 for Figure 1 A floor plan;

[0019] Figure 3 Assembly diagram of the drop hammer self-locking system, drop hammer lifting system, interlocking straightening system, and guide cylinder;

[0020] Figure 4 for Figure 3 Internal structure diagram;

[0021] Figure 5 This is a schematic diagram of a drop hammer self-locking system;

[0022] Figure 6 A schematic diagram of the internal structure of the drop hammer self-locking system;

[0023] Figure 7 This is a schematic diagram of a drop hammer self-locking system;

[0024] Figure 8 This is a schematic diagram of a DLV model;

[0025] Figure 9 This is a schematic diagram of the installation of the DLV head sensor;

[0026] Figure 10 This is a schematic diagram of a ground stake.

[0027] In the diagram: 1-Drop hammer self-locking system; 1.1-Swivel lifting ring; 1.2-Lifting ring fixing rod; 1.3-Unhooking cover; 1.4-Mounting base; 1.5-Electromagnet; 1.6-Drop hammer; 1.7-Unhooking shaft; 1.8-Push rod; 1.9-Ball bearing; 1.10-Push rod cylinder; 1.11-Guide ear; 2-Drop hammer lifting system; 2.1-Lifting motor; 2.2-Electric winch; 2.3-Wire rope; 3-Guide rail; 4-Interlocking and straightening system; 4.1-Mounting frame; 4.2-Snap ring; 4.3-Pull rod; 4.4-Swing arm; 4.5-Trajectory roller; 4.6-Shaft II; 4.7-Snap ring cylinder; 4.8-Mounting plate; 5.1-DLV model; 5.2-DLV head sensor; 6-Photoelectric switch; 7.1-Support frame; 7.2-Upper protection; 7.3-Lower support protection; 7.4-Specimen fixing platform; 8-Guide cylinder; 9-Fixing frame; 10.1-Threaded cylinder; 10.2-Threaded rod; 10.3-Connecting plate. Detailed Implementation

[0028] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1

[0030] This embodiment provides a test bench for the safety performance of falling object protection structures, including a falling hammer self-locking system 1, a falling hammer lifting system 2, and a specimen fixing system.

[0031] The drop hammer self-locking system 1 includes a rotating lifting ring 1.1, a lifting ring fixing rod 1.2, a release cover 1.3, a mounting base 1.4, an electromagnet 1.5, a drop hammer 1.6, a release shaft 1.7, a push rod 1.8, and a push rod drive unit, all arranged coaxially.

[0032] The lifting ring fixing rod 1.2 passes vertically through the top surface of the release cover 1.3; the rotating lifting ring 1.1 is rotatably connected to the portion of the lifting ring fixing rod 1.2 located outside the release cover 1.3; the top surface of the mounting base 1.4 is fixedly connected to the bottom surface of the release cover 1.3, and the bottom surface is fixedly connected to the top surface of the electromagnet 1.5; the bottom surface of the electromagnet 1.5 is electromagnetically attracted to the top surface of the drop hammer 1.6; the top surface of the drop hammer 1.6 has a central blind hole extending axially downwards; the release shaft 1.7 has a central through hole penetrating the top and bottom surfaces, and the release shaft 1.7 vertically penetrates the bottom surface of the release cover 1.3, the mounting base 1.4, and the electromagnet 1.5; the portion below the electromagnet 1.5 is a plug-in section; the plug-in section is used to insert the drop hammer. A radial hole is provided in the central blind hole of 1.6, which communicates with the central through hole. A ball bearing 1.9 is installed in the radial hole. The push rod 1.8 is inserted into the central through hole of the release shaft 1.7. The locking section is within a preset distance from the bottom surface upward (the preset distance is mainly determined according to the length of the central through hole of the release shaft 1.7 and the position of the radial hole). The diameter of the locking section gradually decreases from top to bottom. The top surface of the push rod drive unit is connected to the lifting ring fixing rod 1.2, and the bottom surface is connected to the top surface of the push rod 1.8. It is used to push the push rod 1.8 downward to make the locking section squeeze the ball bearing 1.9 outward to press the drop hammer 1.6 into the central blind hole, and to pull the push rod 1.8 upward to form a radial gap between the locking section and the release shaft 1.7.

[0033] The drop hammer lifting system 2 is connected to the rotating ring 1.1 and is used to lift the drop hammer self-locking system 1 to a preset height.

[0034] The specimen fixing system is installed below the drop hammer 1.6 and is used to fix specimens such as the driver's cab and passenger compartment.

[0035] In the aforementioned test bench for the safety performance of the falling object protection structure, the falling hammer 1.6 is fixed by an electromagnet 1.5, achieving electromagnetic locking of the falling hammer 1.6. The push rod drive unit pushes the push rod 1.8 downward, causing the locking section to squeeze the ball 1.9 outward and press it against the central blind hole of the falling hammer 1.6, achieving mechanical locking of the falling hammer 1.6. The double locking can prevent the falling hammer 1.6 from accidentally disengaging. The falling hammer lifting system 2 lifts the falling hammer self-locking system 1 to the preset position, the electromagnet 1.5 is de-energized, and at the same time, the push rod drive unit pulls the push rod 1.8 upward, forming a radial gap between the locking section and the disengagement shaft 1.7. The locking section no longer squeezes the ball 1.9, the mechanical locking is released, and the falling hammer 1.6 tends to fall freely. The ball 1.9 is squeezed radially inward by the falling hammer 1.6, and the falling hammer 1.6 falls off, achieving free fall impact on the test specimen, completing one test.

[0036] Preferably, when the push rod drive reaches its maximum working stroke, the bottom surface of the push rod 1.8 is flush with the bottom surface of the center blind hole of the drop hammer 1.6, at which time the ball bearing 1.9 firmly locks the drop hammer 1.6.

[0037] The rotating lifting ring 1.1 is rotatably connected by a shaft I perpendicular to the lifting ring fixing rod 1.2, and the rotation angle around shaft I is 0-180°.

[0038] The top surface of the push rod drive unit is connected to the lifting ring fixing rod 1.2 via a traction rope.

[0039] The push rod drive unit is a push rod cylinder 1.10, preferably a single-acting cylinder, which can only operate under power conditions.

[0040] The bottom surface of the hook cover 1.3 has several circular holes evenly arranged, which are fixed to the threaded holes on the mounting base 1.4 by bolts.

[0041] Example 2

[0042] In order to limit the drop hammer 1.6 from deviating from the preset landing point and to prevent the drop hammer 1.6 from sliding off the top of the test specimen such as the cab or passenger compartment during the test, the falling object protection structure safety performance test bench provided in this embodiment is also vertically equipped with multiple guide rails 3, and guide ears 1.11 that cooperate with the guide rails 3 are provided on the hook cover 1.3 and / or mounting base 1.4, and an interlocking straightening system 4 is also provided.

[0043] Multiple guide rails 3 are located above the specimen and are evenly arranged around the central axis of the drop hammer self-locking system 1; the guide ears 1.11 correspond one-to-one with the guide rails 3, and each guide ear 2 is provided with a guide hole that slides outside the guide rail 3.

[0044] In this embodiment, four guide ears 1.11 are provided, divided into upper and lower groups, located on the unhooking cover 1.3 and the mounting base 1.4 respectively.

[0045] The interlocking straightening system 4 includes a mounting frame 4.1, a retaining ring 4.2, a retaining ring drive unit, and a locking tongue. The mounting frame 4.1 is mounted on the bottom surface of the guide rail 3 and has a drop hammer hole that passes through the top and bottom surfaces. The retaining ring 4.2 is rotatably connected to the mounting frame 4.1, and its center is coaxial with the center of the drop hammer hole and the center of the drop hammer. The inner wall of the retaining ring 4.2 is provided with a roller groove. Multiple sets of locking tongues are evenly arranged around the center of the retaining ring 4.2. Each set of locking tongues includes a pull rod 4.3, a swing arm 4.4, and a track roller 4.5. The first end of the pull rod 4.3 is rotatably connected to the retaining ring 4.2 through shaft II 4.6, and the second end is rotatably connected to the first end of the swing arm 4.4 through shaft II 4.6. The second end of the swing arm 4.4 is rotatably mounted with a track roller 4.5 through shaft II 4.6, and the track roller 4.5 slides along the roller groove. The retaining ring drive unit is used to drive the retaining ring 4.2 to rotate and extend or retract the swing arm 4.4.

[0046] The interlocking and centering system 4 works in conjunction with the drop hammer self-locking system 1, and has both interlocking and centering functions.

[0047] Interlocking function: Only when the drop hammer 1.6 falls to the preset start position of the interlocking and straightening system 4 will the buckle drive rotate the buckle 4.2 in the opposite direction to the extreme value, the swing arm 4.4 fully retract, and the locking tongue open, so that the drop hammer 1.6 can fall onto the specimen through the buckle 4.2 and the drop hammer hole. In other cases, the swing arm 4.4 is extended and the locking tongue is in the locked state. When the drop hammer 1.6 deviates during free fall, it prevents the drop hammer from falling further, which can fully ensure the personal safety of the test operator.

[0048] Straightening function: After the drop hammer 1.6 falls and impacts the specimen, the buckle drive rotates clockwise, buckle 4.2 rotates, swing arm 4.4 extends, and the locking tongue clamps and straightens the drop hammer 1.6 so that the central blind hole of the drop hammer 1.6 is aligned with the insertion section of the release shaft 1.7. The remaining part of the drop hammer self-locking system 1, except for the drop hammer 1.6, descends, and the insertion section of the release shaft 1.7 is inserted into the central blind hole of the drop hammer 1.6. When the electromagnet 1.5 is in contact with the drop hammer 1.6, the locking section of the push rod 1.8 squeezes the ball 1.9 to press it tightly against the central blind hole of the drop hammer 1.6, completing the electromagnetic and mechanical synchronous locking. The drop hammer self-locking system 1 is raised to the preset position, and the swing arm 4.4 of the interlocking straightening system 4 continues to extend, so that the locking tongue is in the locked state, which is convenient for the next experiment.

[0049] In this embodiment, the drop hammer hole of the mounting bracket 4.1 is a square hole with rounded right angles, and is installed at a 45° angle to the guide rail 3.

[0050] The buckle drive unit is a buckle cylinder 4.7, preferably a single-acting cylinder, which can only operate under power conditions. Its two ends are connected to the mounting plate 4.8 and the mounting bracket 4.1 on the buckle 4.2 respectively through pin Ⅲ.

[0051] In this interlocking straightening system 4, the contact point between the retaining ring 4.2 and the retaining ring cylinder 4.7, the rotation center of the pull rod 4.3, and the rotation center of the swing arm 4.4 form a self-locking structure. This ensures that the swing arm 4.4 can only disengage under the power of the retaining ring cylinder 4.7. Furthermore, the retaining ring cylinder 4.7 is a single-acting cylinder; when there is no external air source, the air circuit is closed, or there is a sudden power outage, the entire interlocking straightening system 4 remains in a self-locking state, ensuring experimental safety. The second end of the swing arm 4.4 uses a trajectory roller 4.5, which reduces friction, making the self-locking point formed by the contact point between the retaining ring 4.2 and the retaining ring cylinder 4.7, the rotation center of the pull rod 4.3, and the rotation center of the swing arm 4.4 easily broken under the action of the cylinder.

[0052] The aforementioned test bench for the safety performance of the falling object protection structure also includes a control system; the interlocking straightening system 4 also includes a proximity switch, which is installed on the guide rail 3 and located at the preset start position of the interlocking straightening system 4. When the falling hammer 1.6 is detected, the proximity switch transmits a signal to the control system; the electromagnet 1.5, the push rod drive unit, and the buckle drive unit are all controlled by the control system.

[0053] Example 3

[0054] The falling object protection structure safety performance test bench provided in this embodiment also includes a deformation measurement system, an energy verification system, and a test bench frame.

[0055] The deformation measurement system includes a DLV model 5.1, a DLV head sensor 5.2, a 3D coordinate scanner, and a high-speed camera. The DLV model 5.1 is installed inside the specimen. The DLV head sensor 5.2 is implanted in the head of the DLV model 5.1 to automatically sense contact or intrusion of foreign objects and transmit signals to the control system. The 3D coordinate scanner is used to scan the surface shape of the specimen and transmit signals to the control system. Data can be compared by scanning once before and after the test, or by comparing the data from the post-test scan with the 3D model of the specimen to analyze the deformation of the specimen. The high-speed camera is used to record the process of the drop hammer impacting the specimen and transmit signals to the control system. Its height is adjustable.

[0056] The energy verification system includes several photoelectric switches 6 installed on the guide rails; when the photoelectric switches 6 detect the falling hammer 1.6, they transmit a signal to the control system; the control system calculates the magnitude of the acceleration based on the distance between the photoelectric switches 6 and the time it takes for the falling hammer 1.6 to pass through the photoelectric switches 6, and compares it with the gravitational acceleration at the test site to verify the energy of the falling hammer at different heights.

[0057] The test bench includes a support frame 7.1, an upper guard 7.2 positioned above the support frame 7.1, a lower support guard 7.3 positioned below the support frame 7.1, and a specimen fixing platform 7.4 positioned on the lower support guard 7.3. The specimen fixing platform 7.4 is perpendicular to the guide rail 3. The specimen fixing system is installed on the specimen fixing platform 7.4. A guide cylinder 8 is provided outside the guide rail 3 to prevent external influence on the drop hammer 1.6. The guide cylinder 8 is connected to the support frame 7.1 through a fixing frame 9 and is suspended above the specimen.

[0058] The support frame 7.1 is a multi-layer steel frame structure with ladders installed between layers; the upper protection 7.2 includes a steel frame, protective plates, and lightning protection devices. The steel frame is connected to the support frame 7.1, and the protective plates are laid on the outside of the steel frame to form a closed structure that is windproof and rainproof; the lower support protection 7.3 includes a steel frame and protective plates. The steel frame is connected to the support frame 7.1, and the protective plates are laid on the outside of the steel frame; the specimen fixing platform 7.4 is a cast iron platform with external dimensions of not less than 4000mm×2200mm×2500mm and is treated with anti-slip material.

[0059] The specimen fixing system includes a transition plate and multiple ground spikes; the ground spikes include a threaded cylinder 10.1, a threaded rod 10.2, and a connecting plate 10.3; the bottom surface of the threaded cylinder 10.1 is fixed on the specimen fixing platform 7.4; the threaded rod 10.2 is threadedly connected to the threaded cylinder 10.1, and the top end is fitted with the connecting plate 10.3; the transition plate and the connecting plate 10.3 of the multiple ground spikes are detachably connected; the specimen is mounted on the transition plate, and different transition plates can be replaced to accommodate different specimens.

[0060] The drop hammer lifting system 2 includes a lifting motor 2.1, an electric winch 2.2, and a wire rope 2.3. The lifting motor 2.1 and the electric winch 2.2 are both mounted on the fixed frame 8. The lifting motor 2.1 drives the electric winch 2.2 to rotate. The wire rope 2.3 is wound around the electric winch 2.2, and its end is led out and connected to the rotating lifting ring 1.1.

[0061] Because the height of the drop hammer 1.6 directly determines the impact energy value, precise control of its height is crucial to the success of the experiment. The lifting motor 2.1 is controlled by a frequency converter, and the lifting height is fed back in real time by a displacement measuring instrument. When the height approaches the preset level, the lifting rate is adjusted to achieve precise control of the drop hammer 1.6's height and ensure accurate positioning. In the event of a power outage, the lifting motor 2.1 brakes to keep the drop hammer 1.6 stationary, preventing it from falling. Simultaneously, the electric winch 2.2 acts as a fixed pulley, ensuring that the wire rope 2.3 remains centered on the drum when it is winding up. Displacement sensors are installed at the extreme displacement points of the wire rope 2.3 to prevent it from slipping off.

[0062] The control system includes a dedicated computer, circuit breakers, contactors, relays, and switching power supplies. These components are located in the high-voltage area, and the entire control system's power start-up, shutdown, and emergency stop are achieved through a combination of these electrical components. The dedicated computer communicates with each sensor via a bus, and all test control, signal acquisition, data processing, and result analysis are performed through the computer. Various sensors and proximity switches are positioned on their respective locations on the test bench. The control software within the dedicated computer enables automatic control of the test process and automatic display, printing, and curve plotting of test results. It can also evaluate and generate reports based on given indicators and relevant parameters. Experimental results can be output and printed in Word or Excel format, or stored in the software database for later retrieval via the software's data query function.

[0063] During the falling object protection structure test, the specimen is first lifted using an electric hoist and secured with adjustable-height ground spikes and transition plates. Initial parameters are set on a dedicated computer, and the control software, based on feedback from a displacement measuring instrument, controls the drop hammer 1.6 to the desired height. Clicking the release button releases the drop hammer 1.6, allowing it to fall freely to the designated position on the specimen. The drop hammer 1.6 is then straightened using an interlocking straightening system 4 and lifted using a drop hammer lifting system 2, awaiting the next test. A 3D coordinate scanner is used to scan the specimen after the impact of the drop hammer 1.6, allowing for analysis of the specimen's deformation characteristics through before-and-after comparison. A high-speed camera records the entire impact process of the drop hammer 1.6 to ensure the reliability of the test results.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A test bench for the safety performance of falling object protection structures, characterized in that, This includes a drop hammer self-locking system, a drop hammer lifting system, and a specimen fixing system; The drop hammer self-locking system includes a rotating lifting ring, a lifting ring fixing rod, a release cover, a mounting base, an electromagnet, a drop hammer, a release shaft, a push rod, and a push rod drive unit arranged coaxially. The lifting ring fixing rod passes vertically through the top surface of the release cover; The rotating lifting ring and the part of the lifting ring fixing rod located outside the hook release cover are rotatably connected; The top surface of the mounting base is fixedly connected to the bottom surface of the release cover, and the bottom surface is fixedly connected to the top surface of the electromagnet. The bottom surface of the electromagnet electromagnetically attracts the top surface of the falling hammer. The top surface of the falling hammer is provided with a central blind hole along the axial direction downward; The unhooking shaft is provided with a central through hole that passes through the top and bottom surfaces. The unhooking shaft vertically passes through the bottom surface of the unhooking cover, the mounting base, and the electromagnet. The part located below the electromagnet is the plug-in section. The plug section is used to be inserted into the central blind hole of the drop hammer, and is provided with a radial hole that communicates with the central through hole. A ball bearing is installed in the radial hole. The push rod is inserted into the central through hole of the release shaft, and the locking section is within a preset distance from the bottom upwards. The diameter of the locking section gradually decreases from top to bottom. The top surface of the push rod drive unit is connected to the lifting ring fixing rod, and the bottom surface is connected to the top surface of the push rod. It is used to push the push rod downward to make the locking section squeeze the ball to press the center blind hole of the drop hammer, and to pull the push rod upward to form a radial gap between the locking section and the unhooking shaft. The drop hammer lifting system is connected to the rotating ring and is used to lift the drop hammer self-locking system to a preset height; The specimen fixing system is installed below the drop hammer and is used to fix the specimen. The test bench for the safety performance of the falling object protection structure also includes multiple vertically arranged guide rails. Multiple guide rails are located above the specimen and are evenly arranged around the central axis of the drop hammer self-locking system; The unhooking cover and / or mounting base are provided with guide ears that correspond one-to-one with the guide slide rails, and each guide ear is provided with a guide hole that is slidably sleeved on the outside of the guide slide rail; The test bench for the safety performance of the falling object protection structure also includes an interlocking uprighting system; The interlocking straightening system includes a mounting bracket, a buckle, a buckle drive unit, and a locking tongue; The mounting bracket is installed on the bottom surface of the guide rail and is provided with a drop hammer hole that runs through the top and bottom surfaces; The buckle is rotatably connected to the mounting bracket, and its center is coaxially arranged with the center of the drop hammer hole and the center of the drop hammer. The inner wall of the buckle is provided with a roller groove. Multiple sets of locking tongues are evenly distributed around the center of the locking ring, and each set of locking tongues includes a pull rod, a swing arm, and a track roller; The first end of the pull rod is rotatably connected to the buckle, and the second end is rotatably connected to the first end of the swing arm. The second end of the swing arm is rotatably equipped with a track roller, which slides along the roller groove. The buckle drive unit is used to drive the buckle to rotate and extend or retract the swing arm.

2. The test bench for the safety performance of falling object protection structures according to claim 1, characterized in that, It also includes the control system; The interlocking straightening system also includes a proximity switch, which is installed on the guide rail and located at the preset start position of the interlocking straightening system. When the falling hammer is detected, the proximity switch transmits a signal to the control system. The electromagnet, push rod drive, and buckle drive are all controlled by the control system.

3. The test bench for the safety performance of falling object protection structures according to claim 2, characterized in that, It also includes a deformation measurement system; The deformation measurement system includes a DLV model, a DLV head sensor, a three-dimensional coordinate scanner, and a high-speed camera; The DLV model was installed inside the specimen; The DLV head sensor is implanted in the head of the DLV model to automatically detect contact or intrusion of foreign objects and transmit the signal to the control system. The three-dimensional coordinate scanner is used to scan the surface shape of the specimen and transmit the signal to the control system; The high-speed camera is used to record the process of the drop hammer impacting the specimen and transmit the signal to the control system.

4. The test bench for the safety performance of falling object protection structures according to claim 3, characterized in that, It also includes an energy verification system; The energy verification system includes several photoelectric switches mounted on guide rails; When the photoelectric switch detects the falling hammer, it transmits a signal to the control system. The control system calculates the magnitude of acceleration based on the distance between several photoelectric switches and the time it takes for the falling hammer to pass through several photoelectric switches, and compares it with the gravitational acceleration at the test site to verify the energy of the falling hammer at different heights.

5. The test bench for the safety performance of falling object protection structures according to claim 4, characterized in that, Including test benches; The test bench includes a support frame, an upper protection set above the support frame, a lower support protection set below the support frame, and a specimen fixing platform set on the lower support protection. The specimen fixing system is installed on the specimen fixing platform; The guide rail is connected to the support frame via a fixed frame and is suspended above the specimen.

6. The test bench for the safety performance of falling object protection structures according to claim 5, characterized in that, The specimen fixing system includes a transition plate and multiple ground spikes; The ground nail includes a threaded cylinder, a threaded rod, and a connecting plate; The bottom surface of the threaded cylinder is fixed on the specimen fixing platform; The threaded rod is threadedly connected to the threaded cylinder, and a connecting plate is installed at the top. The transition plate and the connecting plate with multiple ground nails are detachably connected; The specimen was mounted on the transition plate.

7. The test bench for the safety performance of falling object protection structures according to claim 6, characterized in that, The push rod drive unit is a push rod cylinder; The drop weight hoisting system includes a hoisting motor, an electric winch, and a wire rope; Both the lifting motor and the electric winch are mounted on a fixed frame, and the lifting motor drives the electric winch to rotate. The wire rope is wound around the electric winch, with its end leading out and connected to the rotating lifting ring; The buckle drive unit is a buckle cylinder, with both ends connected to the buckle and the mounting bracket respectively via pins.

8. The test bench for the safety performance of falling object protection structures according to claim 7, characterized in that, The support frame is a multi-layer steel frame structure, with ladders installed between the layers; The upper protection includes a steel frame, protective plates, and lightning protection devices. The steel frame is connected to the support frame, and the protective plates are laid on the outside of the steel frame. The lower support and protection includes a steel frame and a protective plate. The steel frame is connected to the support frame, and the protective plate is laid on the outside of the steel frame. The specimen fixing platform is a cast iron platform with external dimensions of not less than 4000mm×2200mm×2500mm.

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