Wide-frequency-domain vibration testing device for simulating seismic rock stratum impact dynamics
Through a wide-frequency domain vibration test device that simulates the impact dynamics of seismic rock formations, the problem that existing devices are difficult to meet high-frequency testing and multi-directional vibration is solved, and efficient and comprehensive performance evaluation and stability verification of the product are achieved.
Patent Information
- Application Number
- CN202421771708.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2025-07-01
- Estimated Expiration
- 2034-07-25
AI Technical Summary
The existing vibration testing devices are difficult to meet the high-frequency testing needs of modern electronic products, and the traditional vibration direction is single, so they cannot regulate the power spectrum density waveform, resulting in insufficient testing efficiency and applicability.
A wide-frequency domain vibration test device that simulates the impact dynamics of seismic rock formations is designed, using a pneumatic hammer and a mesh layer structure. Through the high-frequency impact of the pneumatic hammer and the translational positioning of the block seat, a wide-frequency domain vibration covering the three-axis and six degrees of freedom is generated, and the vibration energy is accurately regulated in combination with a closed-loop control system.
It realizes multi-directional and multi-frequency vibration testing of the product under complex vibration conditions, significantly improving the testing efficiency and applicability, and can more comprehensively evaluate the durability and reliability of the product, ensuring stability in extreme environments.
Smart Images
Figure CN223050816U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of high-acceleration life test systems, and particularly relates to a broadband vibration test device for simulating the dynamics of seismic rock stratum impacts. Background Art
[0002] Highly Accelerated Life Test (HALT) is a method of exposing the weak links and potential defects of a product by gradually increasing the stress excitation and testing its limits. It can expose the weak links of the product in a short time, eliminate premature products, quickly identify problems, and then understand and improve the product reliability by analyzing the failure mechanism.
[0003] In Highly Accelerated Life Test (HALT), the random vibration mode adopted is closer to the complex vibration environment in the real world. The three-axis six-degree-of-freedom vibration test method can evaluate the performance and reliability of products under dynamic loads more quickly and comprehensively. Considering that earthquake is one of the vibration types with extremely powerful destructive force and wide frequency spectrum in nature, in order to test products more efficiently, the present invention proposes a broadband vibration test device for simulating the dynamics of seismic rock stratum impacts. The device aims to reproduce earthquake-level vibration conditions by simulating the form of seismic rock stratum impacts, so as to achieve the effect of quickly evaluating the product performance, thereby ensuring the safety and stability of the product in extreme environments.
[0004] With the development trend of electronic and electrical products towards modularization, integration, miniaturization, diversification and personalization, the upper limit of the vibration frequency of the existing vibration tables is usually below 2000Hz, which is difficult to meet the high-frequency test requirements. Moreover, the fixed structure results in a single vibration direction, making it impossible to condition the power spectral density waveform of the tabletop. The traditional single-direction vibration table and low-frequency domain test methods have gradually become difficult to meet the needs of continuous product upgrade and iteration. Therefore, it is necessary to expand the frequency range of vibration tests, especially in the high-frequency band, to adapt to the more delicate structure and higher performance standards of modern electronic products. By adopting a manageable and controllable vibration test device, a power spectral density (PSD) waveform covering a wide frequency domain can be generated to excite the product under test and prompt the product to exhibit its inherent vibration characteristics. This method can not only more comprehensively evaluate the durability and reliability of the product, but also significantly improve the wide applicability and efficiency of the highly accelerated life test to meet the diversity and personalization of product tests and ensure the stable performance of electronic and electrical products in various harsh environments. Summary of the Utility Model
[0005] The utility model relates to a broadband vibration test device for simulating the dynamics of seismic rock stratum impact: The tabletop (1) has a square planar structure, and is provided with a plurality of screw holes thereon for fixing test objects; below the tabletop (1) is provided with a mesh layer (2), the mesh layer (2) is regularly distributed with a plurality of hollow square structures, and a plurality of circular through holes are provided on the narrow sides of the hollow square structures; a square block seat (3) is placed on the mesh layer (2), and a pneumatic hammer (4) is installed on the square block seat (3); square block seats (3) are respectively arranged at the four corners of the mesh layer (2), and cup covers (7) are respectively installed on the square block seats (3) at the four corners; a support spring (8) is arranged in the cup cover (7), and the other end thereof is fixed in a rubber cup pad (9); the rubber cup pad (9) is fixedly installed on a support frame (25); small screw holes a (5) are distributed on the lower periphery of the tabletop (1), and small screw holes c (15) and small screw holes b (6) are respectively provided in the middle parts of the upper and lower surfaces; the device is controlled by a closed-loop control system composed of an electro-pneumatic proportional valve (10), a vibration acceleration sensor (11) and a signal acquisition and processor (12); the mesh layer (2) has a square planar structure, and a plurality of square spaces are formed by hollowing out the middle area, and the narrow sides are reserved at the edges as connection supports; a plurality of circular through holes are provided on the narrow sides for screw connection to realize the fixation of the mesh layer (2) and the tabletop (1); after fixation, the contact between the mesh layer (2) and the tabletop (1) is limited to the narrow side part; the square block seat (3) is designed as a cuboid structure, and its bottom surface is installed on the plane of the mesh layer (2) by screws, and translation positioning is realized through a screw hole array to adjust the position and quantity of the square block seats (3), so as to increase or decrease the quantity of the pneumatic hammers (4); the other side of the square block seat (3) is installed with the pneumatic hammer (4) by a flat-fitting locking method, and the pneumatic hammer (4) can be fixed at any angle within its installation plane; a hammer core (21) is arranged in the pneumatic hammer (4), and the hammer core (21) reciprocates under the push of compressed air, and the impact with the front wall of the sleeve (20) can generate an impact vibration similar to an earthquake; the vibration energy is conducted to the tabletop (1) through the square block seat (3) and the mesh layer (2) to excite broadband vibration, so that the tabletop (1) generates vibration covering three axes and six degrees of freedom; the sleeve (20) of the pneumatic hammer (4) adopts a single-body structure design to simplify the structure; a high molecular material replaces the metal material to reduce the overall weight while meeting the requirements of high and low temperature test environments; the hammer core (21) is designed to be streamlined, with the smallest diameter at the front end, slightly larger diameter in the middle, and the diameter increasing again at the rear end to reduce air resistance; the hammer core (21) is in direct contact with the front wall of the sleeve (20); the electro-pneumatic proportional valve (10) and the signal acquisition and processor (12) are located outside the device; the compressed air is regulated in pressure by the electro-pneumatic proportional valve (10) and then accesses the air inlet hole (24) of the pneumatic hammer (4), and after pushing the hammer core (21), it is discharged out of the device through the air exhaust hole (23) of the pneumatic hammer (4).The described electro-pneumatic proportional valve (10) is used to regulate the compressed air pressure and supply it to the pneumatic hammer (4) to drive the internal vibration mechanism to simulate seismic impacts; the vibration acceleration sensor (11) is fixedly installed at the bottom of the tabletop (1) through the small screw hole b (6), and the collected signal is transmitted to the signal acquisition and processing unit (12) through a dedicated cable; the processed signal is fed back to the electro-pneumatic proportional valve (10) to dynamically adjust the flow rate and pressure of the compressed air, forming a closed-loop control system; a support frame (25) is provided, and the support frame (25) is of a frame structure, baffles can be assembled around it, and it is fixedly connected through the small screw hole a (5) at the bottom of the tabletop (1) to form a heat insulation and isolation barrier.
[0006] The present utility model uses a single polymer material to manufacture the sleeve (20) of the pneumatic hammer (4), which reduces the overall weight of the pneumatic hammer (4) by 40% (compared with the traditional metal structure). At the same time, the single material design avoids the change in the fitting clearance between the sleeve and the hammer core exceeding 0.2 mm caused by the difference in the thermal expansion and contraction coefficients when using two materials to manufacture the sleeve (20) traditionally, thereby eliminating the risk of the pneumatic hammer getting stuck and failing under extreme high and low temperature conditions (-50°C to 130°C). After testing, the failure rate of the improved pneumatic hammer (4) getting stuck in the high and low temperature cycle test has dropped from 15% to 0.5%, and it can withstand the severe environmental challenges in the high acceleration life test, ensuring the continuity and reliability of the test. At the same time, the self-lubricating property of the polymer material helps to reduce the running friction between the hammer core (21) and the sleeve (20), improving the reciprocating motion efficiency of the pneumatic hammer (4).
[0007] The present utility model constructs a multi-source excitation system through the high-frequency impact and quantity / angle adjustment of the pneumatic hammer (4), and the translational positioning of the square block seat (3) on the mesh layer (2), which can drive the tabletop (1) to generate broadband vibration in the range of 2 - 10000 Hz and three-axis six-degree-of-freedom earthquake-like random vibration. This design enables the test platform to more comprehensively test the multi-directional and multi-frequency vibrations that the product may encounter, thereby more efficiently evaluating the performance and structural stability of the product under complex vibration conditions, especially finding the natural frequency of the product in the broadband frequency spectrum and exciting its self-vibration to improve the test efficiency. Description of the Drawings
[0008] Figure 1 is the front view structural schematic diagram of the present utility model;
[0009] Figure 2 is the schematic diagram of the air intake, exhaust and signal connection of the present utility model;
[0010] Figure 3 is the top view of the present utility model;
[0011] Figure 4 is the three-dimensional view of the mesh layer of the present utility model;
[0012] Figure 5 This is a three-dimensional view of the square block seat of the present utility model;
[0013] Figure 6 This is an exploded view of the pneumatic hammer of the present utility model;
[0014] Figure 7 This is a simplified schematic diagram of seismic wave generation;
[0015] Figure 8 This is an installation schematic diagram of the support frame of the present utility model;
[0016] In the figure: 1, tabletop; 2, mesh layer; 3, square block seat; 4, pneumatic hammer; 5, small screw hole a; 6, small screw hole b; 7, cup cover; 8, support spring; 9, rubber cup pad; 10, electro-pneumatic proportional valve; 11, vibration acceleration sensor; 12, signal acquisition and processor; 13, screw hole; 14, screw hole; 15, small screw hole c; 16, hollow square; 17, hollow round hole; 18, hollow through hole; 19, screw hole; 20, sleeve; 21, hammer core; 22, end cap; 23, exhaust hole; 24, air inlet hole; 25, support frame. Specific embodiments
[0017] Next, in combination with the drawings in the embodiments of the present utility model, those skilled in the art can implement according to the description in the specification: Refer to Figures 1 to 8 , a broadband vibration test device for simulating the dynamics of seismic rock layer impact, wherein the tabletop (1) and the mesh layer (2) are fixedly connected through screws to the screw holes (14); the square block seats (3) are installed on the mesh layer (2), and these square block seats (3) can freely translate and adjust their positions within the plane of the mesh layer through the hollow round holes (17) to optimize the layout of the pneumatic hammers (4). The pneumatic hammers (4) are installed on the square block seats (3) and fixed by screws, and can rotate 360° within the plane of the square block seats (3) around the screw fixing points, so as to simulate seismic impact forces in different directions. One square block seat (3) is arranged at each of the four corners of the mesh layer (2), and a cup cover (7) is installed on each square block seat. A support spring (8) is installed inside the cup cover (7), and the other end is fixed inside the rubber cup pad (9). The rubber cup pad (9) is installed inside the support frame (25) to play a role in buffering, shock absorption and support.
[0018] The tabletop (1) is designed as a square planar structure, presenting a regular quadrilateral when viewed from above. The tabletop is made of aluminum alloy material to ensure that it can generate the expected vibration characteristics when subjected to impact excitation. Multiple M10 screw holes are drilled on the tabletop plane in a matrix layout (spacing 100 mm) for fixing the object under test or other components. The tabletop (1) serves as a test platform, receiving and transmitting the vibration energy excited by the pneumatic hammer (4). Through the impact of the pneumatic hammer (4) on the connection structure of the mesh layer (2) and the square block (3), the tabletop (1) is excited to generate broadband random vibration, and then the object under test fixed on the tabletop (1) is excited to respond. Small screw holes c (15) and small screw holes b (6) are respectively provided in the middle of the upper and lower surfaces of the tabletop (1) for fixing sensors; small screw holes a (5) are distributed around the lower periphery of the tabletop (1) for fixing the spacer layer of the support frame (25).
[0019] The mesh layer (2) is designed as a square planar structure, using the same aluminum alloy material as the tabletop (1) to ensure mechanical property matching; multiple square areas are hollowed out in the middle part, and only the narrow edges are retained as connection supports, and multiple circular through holes are further hollowed out on the narrow edges. Screws fasten the mesh layer (2) to the tabletop (1) through the through holes, and the contact area is limited to the width of the narrow edge, so as to reduce unnecessary rigid coupling, allow independent vibration modes, and significantly reduce the weight of the device.
[0020] In the connection structure composed of the mesh layer (2) and the square block (3), the mesh layer (2) serves as the connection foundation, and the square block (3) can move flexibly within its plane to change the relative position between the pneumatic hammer (4) and the tabletop (1), and precisely control the transmission direction and conduction efficiency of the vibration energy. At the same time, both the tabletop (1) and the mesh layer (2) adopt a multi-screw hole design, which is convenient for adjusting or increasing the number of pneumatic hammers (4); the other side of the square block (3) is locked and installed with the pneumatic hammer (4) by plane fitting, and the pneumatic hammer (4) can be fixed at any angle of 360° within the installation plane, so that the vibration spectrum of the tabletop (1) has high adjustability and controllability, and greatly expands the applicability of the device to different test scenarios.
[0021] Refer to Figure 6, the sleeve (20) adopts a streamlined single - body structure. This design not only greatly simplifies the overall structure but also innovatively uses polymer materials to replace the application of traditional metal materials in the sleeve (20). The polymer material has self - lubricity, which can reduce the friction between the hammer core (21) and the sleeve (20), and significantly reduces the weight of the device (40% lighter than the metal structure). At the same time, the material properties enable it to operate well in the high - and - low - temperature environments of high - acceleration life tests. The sleeve (20) is designed with one end closed and one end open; the hammer core (21) is carefully designed into a streamlined structure, with the smallest diameter at the front end, a slightly larger diameter in the middle part, and the diameter increasing again at the rear end. A stepped surface is designed between the middle and the rear end, and the center is designed as a hollow structure with a closed front end, and air holes are evenly distributed around it; the hammer core (21) is inserted into the sleeve (20) from the small - diameter end and blocked with an end cap (22); such a geometric design can effectively reduce the air resistance encountered during impact and is suitable for high - frequency movements. In particular, the hammer core (21) directly impacts the front wall of the sleeve (20), and this layout enables the impact kinetic energy to be transmitted without loss, and the energy conversion efficiency is increased to more than 95%.
[0022] The high - frequency impact action inside the pneumatic hammer (4) can generate earthquake - like shocks. Its working principle is as follows: Compressed air is filled into the hollow cavity of the hammer core (21) through the air inlet hole (24). The front end of the sleeve (20) is provided with an exhaust hole (23). Under the action of the pressure difference, the compressed air is released to the exhaust hole (23) through the air holes of the hammer core (21), pushing the hammer core (21) to impact the front wall of the sleeve (20). When the hammer core (21) impacts the front wall of the sleeve (20), its air holes are precisely aligned with the exhaust hole (23) to complete the impact action. Subsequently, the stepped surface of the hammer core (21) returns under the action of the compressed - air thrust until the hollow cavity is inflated again, entering the next reciprocating impact cycle. The above - mentioned impact energy is efficiently transmitted to the tabletop (1) through the conduction mechanism of the square block base (3) and the mesh layer (2). The tabletop (1) generates a wide - frequency - domain vibration covering three - axis six - degrees - of - freedom by coupling multi - direction excitation forces and vibration waves. This vibration mode can apply multi - direction and multi - dimensional excitations to the object under test fixed on the tabletop to evaluate the structural stability and response characteristics of the object under test
[0023] See Figure 2 , after being precisely controlled by the electro - pneumatic proportional valve (10), the external compressed air is supplied to the pneumatic hammer (4) through the air pipe. Vibration is generated inside the pneumatic hammer (4). The vibration acceleration sensor is fixedly installed at the bottom of the tabletop (1) through the small screw hole b (6). After sensing the vibration, it generates an electrical signal and transmits it to the signal acquisition and processor (12) in real - time through a special cable. The processor sends the signal to the upper computer for analysis and processing, and the processing result is fed back to the electro - pneumatic proportional valve (10) to dynamically adjust the flow rate and pressure of the compressed air, forming a closed - loop control system.
[0024] SeeFigure 7 : Simplified diagram of the shock wave caused by an earthquake. The figure shows the wave form formed when the earthquake shock propagates on the ground. This wave form has complex frequency components and amplitude variations. A broadband vibration test device for simulating the dynamics of earthquake rock stratum impact provided by the present utility model draws on the physical mechanism of the collision of underground rock strata in an earthquake causing ground vibration.
[0025] Refer to Figure 8 , in order to ensure that the vibration test device can operate stably in a variety of temperature environments, a support frame (25) is specially designed. Baffles can be assembled around the support frame, and a heat insulation layer is fixed through the small screw holes a (5) at the bottom of the table top (1), aiming to form a physical barrier under the table top (1) to effectively isolate the influence of the external environmental temperature on the heat conduction of the internal components of the device and improve the use reliability of the device under extreme temperature conditions.
Claims
1. A wide-band vibration test device for simulating earthquake rock impact dynamics, characterized in that: The table top (1) is a square plane structure, and is provided with a plurality of screw holes for fixing the test object; a mesh layer (2) is provided under the table top (1), and the mesh layer (2) has a plurality of hollow square structures regularly distributed thereon, and a plurality of circular through holes are provided on the narrow sides of the hollow square structures; a block seat (3) is placed on the mesh layer (2), and a pneumatic hammer (4) is installed on the block seat (3); the four corners of the mesh layer (2) are respectively provided with block seats (3), and cup covers are respectively installed on the block seats (3) at the four corners (7); a support spring (8) is placed in the cup cover (7), and the other end of the support spring (8) is fixed in the rubber cup pad (9); the rubber cup pad (9) is fixedly mounted to the support frame (25); small screw holes a (5) are distributed on the lower periphery of the table top (1), and small screw holes c (15) and small screw holes b (6) are respectively provided in the middle of the upper and lower surfaces; the device is controlled by a closed-loop control system composed of an electrical proportional valve (10), a vibration acceleration sensor (11) and a signal acquisition and processor (12).
2. A wide-band vibration testing device for simulating earthquake rock impact dynamics according to claim 1, characterized in that: The mesh layer (2) has a square planar structure, the middle area is hollowed out to form a plurality of square spaces, and the edges retain narrow edges as connection supports; a plurality of circular through holes are provided on the narrow edges for screw connection to achieve the fixation of the mesh layer (2) and the table top (1); after fixation, the contact between the mesh layer (2) and the table top (1) is limited to the narrow edge portion.
3. A wide-band vibration testing device for simulating earthquake rock impact dynamics according to claim 1, characterized in that: The block seat (3) is designed as a rectangular parallelepiped structure, the bottom surface of which is installed on the plane of the mesh layer (2) by means of screws, and translation positioning is achieved through a screw hole array to adjust the position and number of the block seat (3), thereby increasing or decreasing the number of pneumatic hammers (4); the other surface of the block seat (3) is installed with the pneumatic hammer (4) in a plane-fitting locking manner, and the pneumatic hammer (4) can be fixed at any angle within its installation plane.
4. A wide-band vibration testing device for simulating earthquake rock impact dynamics according to claim 1, characterized in that: A hammer core (21) is arranged inside the pneumatic hammer (4). The hammer core (21) reciprocates under the impetus of compressed air and collides with the front wall of the sleeve (20) to generate impact vibration similar to an earthquake. The vibration energy is transmitted to the table top (1) through the block seat (3) and the mesh layer (2), thereby exciting wide-band vibration and causing the table top (1) to generate vibration covering three axes and six degrees of freedom.
5. A wide-band vibration testing device for simulating earthquake rock impact dynamics according to claim 1, characterized in that: The sleeve (20) of the pneumatic hammer (4) adopts a single-body structural design to achieve structural simplification; polymer materials replace metal materials to reduce the overall weight while meeting the requirements of high and low temperature test environments; the hammer core (21) is designed to be streamlined, with the smallest diameter at the front end, a slightly larger diameter in the middle, and an increased diameter at the rear end to reduce air resistance; the hammer core (21) is in direct contact with the front wall of the sleeve (20).
6. A wide-band vibration testing device for simulating earthquake rock impact dynamics according to claim 1, characterized in that: The electric proportional valve (10) and the signal acquisition and processor (12) are located outside the device; the compressed air is connected to the air inlet (24) of the pneumatic hammer (4) after the pressure is regulated by the electric proportional valve (10), and is discharged outside the device through the air outlet (23) of the pneumatic hammer (4) after pushing the hammer core (21); the electric proportional valve (10) is used to regulate the pressure of the compressed air and supply it to the pneumatic hammer (4), drive its internal vibration mechanism to simulate earthquake impact, and the vibration acceleration sensor (11) is fastened to the bottom of the table (1) through the small screw hole b (6), and the collected signal is transmitted to the signal acquisition processor (12) via a dedicated cable; the processed signal is fed back to the electric proportional valve (10), and the flow and pressure of the compressed air are dynamically adjusted to form a closed-loop control system.
7. A wide-band vibration testing device for simulating earthquake rock impact dynamics according to claim 1, characterized in that: A support frame (25) is provided. The support frame (25) is a frame structure. Baffles can be installed around the frame and fixedly connected through small screw holes a (5) at the bottom of the table top (1) to form a heat insulation barrier.