A thin plate vibration clanny figure demonstration system

Abstract

This invention relates to the field of physics experimental teaching instruments and discloses a thin-plate vibration Kranney graphic demonstration system, including a frame, an electric vibrator, a thin plate, a gripper mechanism, a sand sprinkler, a sand-blocking curtain, a sand-collecting plate, and a storage box. The electric vibrator is mounted on the frame, and the thin plate is clamped and positioned by the gripper mechanism. The sand sprinkler is located above the thin plate, the sand-blocking curtain surrounds the thin plate, and the funnel-shaped sand-collecting plate is located below the thin plate and communicates with the storage box. This invention ensures reliable vibration of the thin plate through a stable clamping structure and achieves centralized sand collection using the sand-blocking curtain and sand-collecting plate, solving problems such as unstable clamping, sand splashing, and blurred graphics in traditional devices, which is beneficial for subsequent research. The overall structure is simple, stable in operation, clean, and environmentally friendly, suitable for classroom demonstrations and scientific experiments related to acoustics and vibration.

Description

Technical Field

[0001] This invention relates to the field of physics experimental teaching instruments, and in particular to a thin plate vibration Kranney graphic demonstration system. Background Technology

[0002] Cranny figures are classic physical experimental phenomena used to visually demonstrate the vibration modes and standing wave distribution of thin plates. They are widely used in university physics teaching, acoustic experiments, and vibration principle demonstrations. Currently, traditional Cranny figure demonstration devices generally suffer from simple structural design, limited functionality, and poor stability, failing to meet the demands of high-quality teaching demonstrations. In practical use, the thin plate clamping mechanism of traditional devices often employs simple clamping or single-point fixing methods, resulting in uneven clamping force and insufficient rigidity. During vibration excitation, loosening, displacement, and shifting are easily observed, directly altering the inherent vibration characteristics of the thin plate, leading to distorted mode shapes and blurred figures. The connection between the excitation component and the thin plate lacks a reasonable support structure, easily generating eccentric excitation and additional vibration interference, making it impossible to stably output standard vibration waveforms. Furthermore, the sand used in the experiment easily splashes and scatters during vibration, lacking effective anti-splash and recovery structures. This not only wastes sand but also pollutes the experimental platform and surrounding environment, making cleaning difficult and reducing reusability. Furthermore, traditional apparatus frames are mostly simple support structures with poor rigidity and stability, making them prone to resonance and additional vibration during excitation, further affecting the clarity and integrity of the Cranny diagrams. Current technologies lack a systematic demonstration structure integrating stable clamping, reliable excitation, splash prevention, and closed-loop recovery, resulting in poor demonstration effects, cumbersome operation, and low experimental repeatability, failing to meet the requirements of modern physics experimental teaching for intuitive, stable, neat, and efficient demonstrations. Summary of the Invention

[0003] To address the aforementioned technical problems, the present invention adopts the following technical solution: a thin-plate vibration Klani graphic demonstration system, comprising a frame, an electric vibrator, a thin plate, a gripper mechanism, a sand spreader, a sand baffle, a sand receiving plate, a storage box, and a support system; the support system includes a vibrator support base and a gripper mechanism, the vibrator support base being bolted to the bottom of the frame; the output end of the electric vibrator is threadedly connected to a locking nut one, a cross boss, the thin plate, and a locking nut two in sequence from bottom to top; the gripper mechanism is slidably connected to a slide rail on the frame via two upper and lower linear bearing sliders, and clamps the thin plate through a hard rubber clamping layer at the end; the sand spreader is located above the thin plate, and the sand spreader housing is bolted to a lifting device on the frame; the sand baffle is arranged around the thin plate; the sand receiving plate is located below the thin plate, with sand receiving connectors at the four corners, and is bolted to the frame through the sand receiving connectors; the outlet of the sand receiving plate is connected to the storage box.

[0004] Furthermore, the support system includes a vibrator support base and a gripper mechanism; the electric vibrator is bolted to the vibrator support base.

[0005] Furthermore, the gripper mechanism is driven by a geared motor. The rotor of the geared motor is equipped with a second bearing, which is connected to a coupling. The coupling is rotatably connected to a lead screw. The gripper mechanism is slidably connected to the slide rail of the frame via two linear bearing sliders. The linear bearing sliders are equipped with a cover plate and four handle bolts. The cover plate is equipped with two angle brackets and is bolted to the optical shaft, the lower upright plate, and the fixed seat. The optical shaft is equipped with a three-sided connector, which is bolted to the upper upright plate. Sand baffles are bolted to both sides of the lower upright plate. The lower upright plate and the upper upright plate are equipped with a hard rubber clamping layer at their ends, which is adjustable through a waist-shaped hole. The lower cover plate is equipped with a first bearing that is clearance-fitted to the lead screw and is sleeved on the rod body. The lead screw is equipped with a nut seat, which is bolted to the locking nut and the three-sided connector, and is threaded to the lead screw. The upper end of the lead screw is equipped with the coupling. An upper plate is provided between the coupling and the geared motor, and the geared motor is bolted to the upper plate.

[0006] Furthermore, the frame is an aluminum profile structure, with foot cup connecting plates at the four corners of the bottom of the frame, and the leveling feet are bolted to the foot cup connecting plates; the bottom of the frame is provided with an end face connecting plate and bolted to the vibrator support seat, the back of the frame is provided with a slide rail, and the top is provided with a guide frame.

[0007] Furthermore, the sand spreader housing is bolted to the lifting device, and a motor bracket and a drive motor are provided on the sand spreader housing; the drive motor is connected to the motor bracket and is connected to the cam drive; a sand spreading cover is provided inside the housing, and a sand spreading tank is provided below the sand spreading cover; the sand spreading tank has a side mounting hole, and a guide key passes through the hole, with the end of the guide key aligned with the external cam; the sand spreading cover has semi-circular and square through holes on both sides; the guide key has a through hole with a diameter slightly smaller than the side length of the square through hole, which coincides with the axis of the square through hole along the transmission direction; the bottom of the sand spreading tank has 6 to 12 outlet holes symmetrically arranged on the side opposite the semi-circular hole, with the diameter of the holes set to 8 to 10 times the average particle size of the sand, about 2 to 3 mm; the other side of the sand spreading tank has a plum blossom-shaped discharge hole coaxial with the square through hole.

[0008] Furthermore, the lifting device has a lifting stroke of 100mm, and its top is provided with a corner bracket 1, and a slider nut 1 and a slider nut 2 are slidably connected to the guide frame. Above the slider nut 1 and the slider nut 2, a handle bolt 1 and a handle bolt 2 are respectively provided; below the corner bracket 1, there is a stop block, below the stop block, there is a slider nut 3, and on the slider nut 3, there is a handle bolt 3.

[0009] Furthermore, the sand-blocking curtain is equipped with a driving device; motor bracket two is fixed to the frame by bolts, drive motor two is fixed to motor bracket two and connected to pulley for transmission; the pulley is provided with a round belt and is connected to the driven pulley on curtain rod one for transmission; curtain rod one and curtain rod two are meshed with each other by bevel gears; the bevel gears, copper sleeves, and fixing rings are sequentially provided at the ends of curtain rod one and curtain rod two; a curtain rod bracket is provided outside the copper sleeve, and the curtain rod bracket is fixedly connected to the fixing ring; the curtain rod bracket is fixedly connected to the frame by bolts; a transparent curtain one is provided below curtain rod two; a transparent curtain two is provided below curtain rod two; both transparent curtain one and transparent curtain two are divided into multiple strip curtains, each strip curtain having a width between 15 and 20 mm and a length between 160 and 180 mm; the upper edge of the curtain strip is 150 to 170 mm above the board surface; the four corners of the sand-blocking curtain are provided with thin walls that are fastened to the frame by bolts; corner curtains are provided below the thin walls.

[0010] Furthermore, the sand receiving plate has a funnel-shaped structure, with a vertical distance of 15 to 30 mm from the thin plate and a side length of 340 to 440 mm; sand receiving connectors are provided at the four corners of the sand receiving plate, and the sand receiving connectors are fixedly connected to the frame; the sand receiving plate wall has perforations, through which the optical axis passes; the sand receiving plate and the sand-blocking curtain together constitute a sand grain recovery structure.

[0011] The invention features a rigid structure, stable operation, reliable clamping, and excellent excitation effect. It can effectively suppress excessive vibration and sand splashing, significantly improve the clarity of the Kroni graphic and the experimental demonstration effect. The overall device is easy to operate, convenient to maintain, environmentally friendly and clean, and is suitable for acoustic and vibration-related physics experiments and scientific demonstrations in universities, middle schools and research institutions. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall assembly structure of the present invention in its working state.

[0013] Figure 2 This is a perspective view of the frame structure of the present invention.

[0014] Figure 3 This is a perspective view of the gripper mechanism of the present invention.

[0015] Figure 4 This is a cross-sectional view of the gripper mechanism of the present invention.

[0016] Figure 5 This is a perspective view of the sand spreader structure of the present invention.

[0017] Figure 6 This is a schematic diagram of the bottom hole of the sand spreader of the present invention.

[0018] Figure 7 This is a perspective view of the lifting device of the present invention.

[0019] Figure 8 This is a schematic diagram showing the connection between the electric oscillator and the thin plate on top of the present invention.

[0020] Figure 9 This is a perspective view of the sand receiving plate structure of the present invention.

[0021] Figure 10 This is a perspective view of the sand-blocking curtain structure of the present invention.

[0022] Figure 11 This is a cross-sectional view of the sand-blocking curtain structure of the present invention.

[0023] Figure 12 This is a schematic diagram of the cross-shaped groove at the bottom of the thin plate of the present invention.

[0024] In the diagram: 1. Frame; 101. Leveling feet; 102. Vibrator support; 103. Foot cup connecting plate; 104. End face connecting plate; 105. Slide rail; 106. Guide frame; 2. Electric vibrator; 201. Locking nut one; 202. Cross boss; 203. Locking nut two; 3. Storage box; 4. Thin plate; 5. Sand spreader; 501. Outer shell; 502. Lifting device; 503. Angle bracket one; 504. Handle Bolt 1; 505, Stop; 506, Slider Nut 1; 507, Motor Bracket 1; 508, Drive Motor 1; 509, Cam; 510, Sand Spreading Cover; 511, Sand Spreading Tank Body; 512, Guide Key; 513, Handle Bolt 2; 514, Slider Nut 2; 515, Handle Bolt 3; 516, Slider Nut 3; 6, Gripper Mechanism; 601, Fixed Base; 602, Linear Bearing Slider; 603, Lead Screw; 6 04. Cover plate; 605. Angle bracket two; 606. First bearing; 607. Handle bolt four; 608. Nut seat; 609. Locking nut three; 610. Coupling; 611. Second bearing; 612. Upper plate; 613. Gear motor; 614. Optical shaft one; 615. Upper upright plate; 616. Hard rubber clamping layer; 617. Sand baffle; 618. Lower upright plate; 619. Three-sided connector; 7. Sand curtain; 701 702. Motor bracket 2; 703. Drive motor 2; 704. Drive pulley; 705. Round belt; 706. Driven pulley; 707. Curtain rod 1; 708. Curtain rod 2; 709. Bevel gear; 710. Copper sleeve; 711. Fixing ring; 712. Curtain rod bracket; 713. Transparent curtain 1; 714. Transparent curtain 2; 715. Thin-walled curtain; 716. Corner curtain; 807. Sand receiving plate; 808. Optical shaft 2; 809. Sand receiving connector. Detailed Implementation

[0025] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0026] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0027] Figures 1 to 12 This is a preferred embodiment of the present invention.

[0028] like Figure 1 and Figure 2As shown, this embodiment provides a thin plate vibration Kroni graphic demonstration system, including a frame 1, an electric vibrator 2, a thin plate 4, a gripper mechanism 6, a sand spreader 5, a sand baffle 7, a sand receiving plate 8, a storage box 3, and a support system. The frame 1 serves as the overall support foundation and is located at the bottom of the system; the electric vibrator 2 is mounted on the vibrator support seat 102 at the bottom of the frame 1, and its output end is connected to the thin plate 4; the thin plate 4 is horizontally arranged in the middle of the system and is clamped and fixed by the gripper mechanism 6; the sand spreader 5 is located above the thin plate 4 and is connected to the lifting device 502, which can realize movement and height adjustment; the sand baffle 7 is arranged around the thin plate 4, the sand receiving plate 8 is located below the thin plate 4, and the storage box 3 is connected to the discharge port of the sand receiving plate 8. The positions of each component are clearly defined and the layout is reasonable. It can complete the clamping, spreading, vibration imaging and sand recovery in sequence according to the demonstration process. Before the system starts working, the sand spreader 5 is slid away along the guide frame 106 connected to the frame 1 through the lifting device 502 to provide operating space for the placement of the thin plate 4 and avoid installation interference. The thin plate 4 is preferably a square plate with a thickness of 1mm and a side length of 300mm. The output shaft of the electric vibrator 2 is preferably 60mm. The thin plate 4 is fitted onto the cross boss 202 through the cross groove at its bottom and is driven and cooperated with the output shaft of the electric vibrator 2. It is rotated 45° around the output shaft and the upper and lower clamping nuts are tightened to ensure that the position of the thin plate 4 is fixed, so that the vertical distance between the thin plate 4 and the bottom of the handle bolt 3 515 is between 160 and 200mm, ensuring that the excitation force can be stably and evenly transmitted to the thin plate 4. The frame 1 is constructed using aluminum alloy profiles, forming a cubic frame structure. It consists of four main columns, multiple crossbeams, and diagonal braces, fastened together with corner fittings and bolts to create a high-rigidity, lightweight support skeleton. Adjustable leveling feet 101 are located at the four corners of the frame 1's bottom, allowing for leveling of the entire machine via threaded adjustment, ensuring system stability under varying ground conditions. A vibrator support seat 102 is mounted on the bottom crossbeam of the frame 1. This support seat is made of thick steel plate and employs a topology-guided structural design, optimizing its stiffness and natural frequency through multi-objective optimization. The optimized vibrator support seat 102 features two crossbeams with a preferred width of 60mm, a thickness of 30mm, and a spacing of 60mm. While ensuring structural strength, the weight is reduced and dynamic performance is improved. The support base is fastened to the frame profile with bolts, and positioning holes and mounting grooves are machined on it to fix the electric vibrator 2, ensuring that the output axis of the vibrator is strictly aligned with the center of the thin plate 4. A horizontal slide rail 105 is provided in the middle of the frame. It adopts a high-precision linear guide rail to provide guidance and support for the gripper mechanism 6 and the lifting device 502, ensuring their movement accuracy and stability. The electric vibrator 2 is an electromagnetic or piezoelectric vibrator. Its housing is fixed to the vibrator support base 102 with bolts. The output axis passes through the center hole of the thin plate 4 upward to ensure lossless transmission of the excitation force. The upper surface of the thin plate 4 is the demonstration working surface, which is required to be flat and free of scratches to ensure uniform distribution of sand particles.

[0029] like Figure 3 and Figure 4 As shown, after the thin plate 4 is installed in place, it is clamped and fixed by the gripper mechanism 6. The gripper mechanism 6 consists of two symmetrically arranged clamping units with a modular design. The upper plate 615 and lower plate 618 of the gripper mechanism 6 can be interchanged as needed, facilitating quick replacement of the clamping components according to the material and thickness of the thin plate 4. Each unit slides along the frame slide rail 105 via a linear bearing slider 602, allowing adjustment of the clamping position along the slide rail direction. It is locked using the handle bolts 607 on each linear bearing slider 602 to accommodate thin plates 4 of different sizes, ensuring the fixation of the gripper mechanism 6 and enabling the performance of the Cranny pattern experiment under external force. 602 is provided with a cover plate 604, on which a second angle bracket 605 is provided, and on the second angle bracket 605 a fixed seat 601 is provided. The fixed seat 601 is fixedly connected to two optical shafts 614. The fixed seat 601 at the lower end of the gripper mechanism 6 is bolted to the lower upright plate 618. The power of the gripper mechanism 6 is provided by a geared motor 613. The geared motor 613 is preferably a JGY3712V type, with a speed of 30 rpm, which can provide a positive pressure of about 2000N. It is bolted to the upper plate 612. Its output shaft is connected to the coupling 610 through the second bearing 611. The coupling 610 is threaded to the top of the lead screw 603. The locking nut 609 is bolted to the nut seat 608, which is connected to the upper plate 615 via a three-sided connector 619. The bottom of the lead screw 603 is clearance-fitted with the first bearing 606. When the lead screw 603 rotates, the nut seat 608 moves up and down along the axis of the lead screw 603, driving the upper plate 615 to move up and down, thereby realizing the gripping and releasing of the gripper mechanism 6. To meet the structural stiffness and dynamic response requirements of the system under extreme high-frequency vibration conditions of around 1000Hz, the length is preferably 260mm, the width is 6mm, and a waist-shaped hole with a total length of 60mm is provided at the end. An adjustable hard rubber clamping layer 616 is connected inside the hole. The clamping layer 616 is preferably a high-hardness rubber with a Shore hardness of 90HA, a side length of 20mm, and a thickness of 10mm. The surface is processed with fine textures to increase the friction with the thin plate 4 and prevent scratches on the surface of the thin plate 4. Sand baffles 617 are provided on both sides of the lower upright plate 618 to effectively prevent sand particles from entering the inside of the gripper and prevent the movement of the lead screw 603, the first bearing 606, etc. from jamming. The unit group of the gripper mechanism 6 can operate independently and achieve bilateral clamping of the thin plate 4 through the control system, reducing the flatness error of the thin plate 4 after clamping. After the gripper mechanism 6 completes the clamping of the thin plate 4, the thin plate 4 is in a horizontal, stable, and vibratory state, providing reliable support conditions for the formation of the Clani pattern.

[0030] like Figure 5 , Figure 6 and Figure 7As shown, after the thin plate 4 is clamped, the sand spreader 5, together with the lifting device 502, is moved back to the position directly above the thin plate 4 along the guide frame 106, and the height between the sand spreader 5 and the thin plate 4 is adjusted by the lifting device 502. The lifting stroke of the lifting device 502 is preferably 100mm, and a stop block 505, an angle bracket 1 503, a slider nut 3 516, and a handle bolt 3 515 are set to limit the lifting and movement of the sand spreader 5, so that the lifting action is smooth and without swaying. The lifting device 502 slides on the guide frame 106 of the machine frame with the lubricant through the slider nut 1 506 and the slider nut 2 514, so that the movement is smooth and the wear is small. After reaching the target position, it is reliably locked by the handle bolt 1 504 and the handle bolt 2 513. After adjustment, the sand particles can be evenly and stably sprinkled onto the surface of the thin plate 4; the outer shell 501 of the sand spreader 5 is equipped with a motor bracket 507, and the drive motor 508 is fixed on the bracket, with its output shaft connected to the cam 509; the sand spreading tank 511 has a side mounting hole, and a guide key 512 passes through the hole, with the end of the guide key 512 aligned with the external cam 509; the sand spreading cover 510 has semi-circular and square through holes on both sides; the guide key 512 has a through hole with a diameter slightly smaller than the side length of the square through hole, coinciding with the axis of the square through hole along the transmission direction; the sand spreading... The bottom of the sand tank 511 preferably has six symmetrical outlet holes with a diameter of 2mm on the side facing the semi-circular hole, which can be used for coarse and rapid sand distribution; the other side of the sand tank 511 has a plum blossom-shaped discharge hole coaxial with the square through hole; when the drive motor 508 rotates, the cam 509 drives the guide key 512 to periodically extend and retract, so that the fine sand particles on the sand distribution cover 510 are evenly distributed onto the surface of the thin plate 4 below through the plum blossom-shaped discharge hole. The amount of sand distributed can be precisely controlled by adjusting the motor speed and the sand distribution time to ensure uniform particle density and avoid uneven distribution of sand by manual distribution, which may cause blurry graphics. like Figure 12 As shown, after the sand grains are distributed, the electric vibrator 2 operates under the control of the external signal generation and processing system, converting electrical energy into mechanical vibration and generating an excitation signal with stable frequency and uniform amplitude. The vibration energy is transmitted to the thin plate 4 through the output end of the electric vibrator 2, causing the thin plate 4 to vibrate stably according to its inherent vibration mode. In this way, the sand grains scattered on the surface of the thin plate 4 gather and arrange towards the vibration node area under the action of vibration, and finally form a clear, regular and intuitively observable Krahni pattern on the thin plate 4, realizing the visualization demonstration of the vibration mode.

[0031] like Figure 10 and Figure 11As shown, during vibration imaging, the sand-blocking curtain 7 is arranged in a closed manner around the thin plate 4. The motor bracket 701 is fixed to the frame 1, and the drive motor 702 drives the active pulley 703 to rotate, which in turn drives the driven pulley 705 and the curtain rod 706 to rotate through the circular belt 704. The curtain rod 706 and the curtain rod 707 are driven by the meshing of the bevel gear 708 to achieve stable deployment of the transparent curtain 712 and the transparent curtain 713. The curtain rod bracket 711, the copper sleeve 709, and the fixing ring 710 provide support and positioning for the curtain rod, ensuring smooth movement. Corner curtains 715 are installed under the thin wall 714 at the four corners to form a closed enclosure, effectively preventing sand particles from splashing to the four corners during vibration and ensuring a clean demonstration environment. The sand-blocking curtain 7 is a transparent flexible curtain that surrounds the thin plate 4, consisting of transparent curtain 712, transparent curtain 713, corner curtains 715, and a curtain rod drive system. The material is PVC transparent strip curtain, with each strip preferably 15mm wide and 180mm long. Preferably, the upper edge of the curtain extends 170mm above the panel surface, ensuring clear visibility for easy observation of the Clani graphic while effectively blocking sand splashes. The drive system consists of a second drive motor 702, a driving pulley 703, a driven pulley 705, a circular belt 704, a first curtain rod 706, a second curtain rod 707, and a bevel gear 708. The second drive motor 702 is fixed to the second motor bracket 701 and drives the first curtain rod 706 to rotate via belt drive. The power is then transmitted to the adjacent second curtain rod 707 via the bevel gears 708 at the four corners, achieving synchronous rotation of the four curtain rods and thus smoothly unfolding or retracting the curtain. The two ends of the curtain rod are supported by curtain rod brackets 711, which contain copper sleeves 709 and fixing rings 710 to reduce friction and ensure smooth rotation of the curtain rod. The corner curtains 715 at the four corners are triangular flexible sheets that complete the sand-blocking range of the four-sided curtain body, forming a completely enclosed enclosure that confines sand particles to the demonstration area above the thin plate 4.

[0032] like Figure 9As shown, the splashed and scattered sand particles fall into the sand receiving plate 8 located below the thin plate 4 under the guidance of the sand-blocking curtain 7. The sand receiving plate 8 is funnel-shaped and preferably set at a vertical distance of 30mm from the thin plate 4, with a side length of 440mm to prevent sand particles from splashing outwards. Its inclination angle is preferably 30° to prevent sand particles from splashing outwards and from accumulating on the plate surface without sliding down. The sand receiving plate 8 is made of multiple acrylic plates spliced ​​together. The upper opening size is larger than that of the thin plate 4, and the lower opening corresponds to the storage box 3. The four corners of the sand receiving plate 8 are fastened to the frame 1 by sand receiving connectors 802. The inner sidewall of the plate is fixed by two optical axes 801, which can also resist the deformation of the large area acrylic plate due to installation and stress, improve the structural rigidity, and prevent deformation after long-term use. The splashed and scattered sand particles gather along the inclined surface of the sand receiving plate 8 to the bottom discharge port and slide into the storage box 3 through the discharge port. The storage box 3 has a drawer-type structure and can be pulled out from the side of the frame 1 for easy cleaning and replenishment of sand, realizing automatic collection and recycling of sand, improving material utilization, and ensuring a continuous and efficient demonstration process.

[0033] like Figure 8 As shown, the frame 1 and the support system ensure overall stability, and the topology-optimized exciter support 102 improves the dynamic performance of the system; the thin plate 4 is fixed to the exciter output shaft through the cross boss 202, locking nut 1 201 and locking nut 203, realizing accurate vibration transmission and 360° free fixation of the thin plate plane, thereby increasing the constraint range of the gripper mechanism 6, which is beneficial for subsequent research; the modular gripper mechanism 6 and the slider component located on the frame 1 realize the rapid clamping and precise positioning of the thin plate 4; and according to the formula; ; The vibration frequency =1000Hz; Thin plate quality =0.3kg; vibration amplitude =0.1mm; static friction coefficient =0.7, the calculation yields ≥1691.93N, in this embodiment the clamping force limit is approximately 2000N, exceeding the calculated data, ensuring the clamping and fixing of the thin plate during the experiment; the upper and lower vertical plates of the clamping jaws are provided with a hard rubber clamping layer 616, according to the formula: ; Thin plate quality =0.3kg; vibration frequency =1000Hz; vibration amplitude =0.1mm; static friction coefficient =0.7; Total number of rubber indenters =2; Radial stiffness of a single rubber indenter =50000, the calculated minimum compression amount is =16.92mm, in this example, both clamping layers 616 on the gripper are selected with a compression amount of 16.92mm. The rubber pressure head ensures that positive pressure is effectively applied to the thin plate to fix it in place; the lifting device 502 with limit, orientation, damping and locking functions ensures a stable and reliable granulation process, according to the formula: ; The width of the effective coverage area of ​​the thin plate 4 =300mm; Diffusion angle of freely falling sand grains =35°, calculated as follows =214mm, which conforms to the lifting height range given in this embodiment, ensuring that the sand particles cover the plate surface as much as possible without being too concentrated or spilling out of the plate; the electric vibrator 2 provides stable excitation; the sand curtain 7 and the sand receiving plate 8 complete the anti-splashing and sand particle recovery. The system operates smoothly, is easy to operate, vibrates stably, and produces clear and intuitive images. It can efficiently and reliably demonstrate the formation process of the Cranny pattern of thin plate vibration, and has good demonstration effect and experimental application value.

[0034] This invention is not limited to the specific embodiments described above. Any modifications made by those skilled in the art based on the above concept without creative effort are within the protection scope of this invention.

Claims

1. A thin sheet vibration claniogram demonstration system, characterized by: The system includes a frame (1), an electric vibrator (2), a storage box (3), a thin plate (4), a sand spreader (5), a gripper mechanism (6), a sand curtain (7), a sand receiving plate (8), and a support system. The electric vibrator (2) is mounted on the frame (1) via a vibrator support base (102). The vibrator support base (102) is designed with topology optimization. Based on the working frequency of the vibrator and the load-bearing requirements of the beam, the stiffness and natural frequency of the support base structure are matched and optimized. After optimization, the width of the two crossbeams of the vibrator support base (102) is 50 mm. The thickness is 25 to 30 mm, and the spacing is 50 to 60 mm. The output end of the output shaft of the electric vibrator (2) is provided with an external thread and is fitted with locking nut one (201) and locking nut two (203). A cross boss (202) is provided above the locking nut one (201) and is threaded to the output shaft. The lower end face and the upper end face of the cross boss (202) are both friction surfaces, and a threaded hole is drilled in the center. The thin plate (4) is a square plate with a thickness of 1 to 2 mm and a side length of 250 to 300 mm, and a threaded hole is provided in the center. It has a threaded through hole, which is driven and cooperates with the output shaft of the electric vibrator (2); the center of the thin plate (4) is also provided with a cross groove that matches the cross boss (202), and the surface of the cross groove is a friction surface; the thin plate (4) is detachably mounted on the cross boss (202) through the cross groove, and the cross boss (202) is pressed and fixed above the thin plate (4) by the locking nut (203) on the output shaft, so as to realize the rotatable, detachable and fixed conditions of the thin plate (4), thereby increasing the area of ​​constraint influence; the The gripper mechanism (6) is slidably connected to the slide rail (105) of the frame (1) via the linear bearing slider (602), increasing the constraint points, expanding the constraint range and clamping the thin plate (4); the sand spreader (5) is located above the thin plate (4); the sand curtain (7) is arranged around the thin plate (4); the sand receiving plate (8) is a funnel-shaped structure with a side length of 330mm to 450mm and an inclination angle of 25° to 30°, and is located below the thin plate (4); the discharge port of the sand receiving plate (8) is connected to the storage box (3).

2. A thin sheet vibration claniograph demonstration system according to claim 1, characterized in that: The support system includes a vibrator support base (102) and a gripper mechanism (6), and the electric vibrator (2) is bolted and fixedly installed on the vibrator support base (102).

3. A thin sheet vibration claniograph demonstration system according to claim 2, wherein: The gripper mechanism (6) is driven by a geared motor (613). The rotor of the geared motor (613) is equipped with a thrust bearing (611) and connected to a coupling (610). The coupling (610) is rotatably connected to a lead screw (603). The upper and lower linear bearing sliders (602) are equipped with a cover plate (604) and a handle bolt (607). Angle bracket two (605) is provided on the cover plate (604), and a fixed seat (601) is provided on the angle bracket two (605). (605) is bolted to the optical axis (614), the lower plate (618), and the fixing seat (601). The optical axis (614) is provided with a three-sided connector (619), which is bolted to the upper plate (615). The lower plate (618) has sand baffles (617) bolted to both sides. The lower plate (618) and the upper plate (615) are right-angled trapezoids. Bolt holes are reserved on both sides of the upper and lower plates, and rigid locking is achieved by bolts and nuts. To meet the structural stiffness and dynamic response requirements of the system under extreme high-frequency vibration conditions around 1000Hz, the upright plate is made of high-rigidity metal sheet with a length of 250 to 260 mm and a width of 6 to 8 mm. It also has a waist-shaped hole at the end with a total length of 40 to 60 mm, through which a rigid rubber clamping layer (616) is tunably connected. The rigid rubber clamping layer (616) is made of high-hardness rubber. A first bearing (606) is provided on the lower cover plate (604). The screw (603) is fitted with a clearance fit and is mounted on the rod body; the screw (603) is provided with a nut seat (608), which is bolted to the locking nut (609) and the three-sided connector (619), and threaded to the screw (603); the upper end of the screw (603) is provided with the coupling (610), and an upper plate (612) is provided between the coupling (610) and the geared motor (613), and the geared motor (613) is bolted to the upper plate (612).

4. The thin-plate vibration claniograph demonstration system according to claim 3, characterized by: The frame (1) is an aluminum profile frame structure. The crossbeam and diagonal beam on the same side as the gripper mechanism (6) are arranged in a symmetrical structure. They are all fixed by welding or corner brackets, and the contact surface angle is 45°. The bottom of the frame (1) is provided with an end face connecting plate (104) and fixedly connected to the vibrator support seat (102). The bottom four corners of the frame (1) are provided with foot cup connecting plates (103), and the leveling feet (101) are bolted to the foot cup connecting plates (103). The back of the frame (1) is provided with a slide rail (105), and the top is provided with a guide frame (106).

5. The thin-plate vibration Cranny graphic demonstration system according to claim 4, characterized in that: The outer shell (501) of the sand spreader (5) is bolted to the lifting device (502), and the lifting device (502) is slidably connected to the frame (1); a motor bracket (507) and a drive motor (508) are provided on the outer shell (501), and the output shaft of the drive motor (508) is connected to the cam (509) for transmission; a sand spreading cover (510) and a sand spreading tank (511) are provided inside the outer shell (501); the sand spreading tank (511) has a side mounting hole, and a guide key (512) is inserted in the hole, with the end of the guide key (512) connected to the cam. The external cam (509) is kept in a positive alignment; the sand-spreading cover (510) has semi-circular and square through holes on both sides; the guide key (512) has a through hole with a diameter slightly smaller than the side length of the square through hole, which coincides with the axis of the square through hole along the extension and retraction direction of the guide key (512); the bottom of the sand-spreading tank (511) has 6 to 12 outlet holes symmetrically arranged on the side opposite to the semi-circular hole, with the diameter of the holes set to 8 to 10 times the average particle size of the sand, about 2 to 3 mm; the other side of the sand-spreading tank (511) has a plum blossom-shaped discharge hole coaxial with the square through hole.

6. The thin-plate vibration Clanney graphic demonstration system according to claim 5, characterized in that: The height of the bottom of the lifting device (502) from the thin plate must meet the following formula: ； in The vertical drop height from the discharge hole to the thin plate (4) is expressed in L. The width of the effective coverage area of ​​the thin plate (4) is expressed in L. The diffusion half-angle of the sand grains falling freely is dimensionless; the top of it is provided with a corner code one (503), and is provided with a slider nut one (506) and a slider nut two (514) which are slidably connected to the guide frame (106). Above the slider nut one (506) and the slider nut two (514) are respectively provided with a handle bolt one (504) and a handle bolt two (513); a stop block (505) is provided below the corner code one (503), and a slider nut three (516) is provided below the stop block (505). A handle bolt three (515) is provided on the slider nut; with the corner code one (503) and the stop block (505) as the upper and lower limits, the lift of the sand spreader (5) is 100mm.

7. The thin-plate vibration Cranny graphic demonstration system according to claim 6, characterized in that: The sand-blocking curtain (7) is equipped with a driving device. The motor bracket two (701) is bolted to the frame (1). The driving motor two (702) is connected to the driving pulley (703) and is driven by the driven pulley (705) through the round belt (704). The driven pulley (705) is fixedly connected to the curtain rod one (706). The curtain rod one (706) and the curtain rod two (707) are meshed with each other through the bevel gear (708). The bevel gear (708), the copper sleeve (709), and the fixing ring (710) are arranged sequentially at the ends of the curtain rod one (706) and the curtain rod two (707). The copper sleeve (709) is provided with a curtain rod bracket (711). (711) is fixedly connected to the fixing ring (710); the curtain rod bracket (711) is bolted to the frame (1); a transparent curtain (712) is provided under the second curtain rod (707); a transparent curtain (713) is provided under the first curtain rod (706); the first transparent curtain (712) and the second transparent curtain (713) are both divided into multiple strips of curtain, each strip of curtain has a width between 15 and 20 mm and a length between 160 and 180 mm; the upper edge of the curtain is 150 to 170 mm above the board surface; the sand-blocking curtain (7) has thin walls (714) at the four corners that are bolted to the frame (1); a corner curtain (715) is provided under the thin walls (714).

8. The thin-plate vibration Cranny graphic demonstration system according to claim 7, characterized in that: The vertical distance between the sand receiving plate (8) and the thin plate (4) is 15 to 30 mm, and the side length is 340 to 440 mm. Sand receiving connectors (802) are provided at the four corners. The sand receiving connectors (802) are fixedly connected to the frame (1). The wall of the sand receiving plate (8) is provided with perforations, and the optical axis (801) passes through the perforations. The sand receiving plate (8) and the sand-blocking curtain (7) together constitute a sand grain recycling structure.

9. A thin-plate vibration Cranny graphic demonstration system according to claim 8, characterized in that: When the gripper mechanism (6) does not apply a clamping constraint to the thin plate (4), the minimum clamping force of the gripper mechanism (6) must satisfy the following formula: ； in This represents the minimum total clamping force of the grippers, with dimensions: M·L·T -2 ; This indicates the mass of the clamped thin plate, with dimensions in meters (m). Represents the vibration frequency, dimensionless: T -1 ; Represents the amplitude of vibration, dimensionless: L; This represents the static friction coefficient between the rubber and the sheet metal, and is dimensionless.

10. A thin-plate vibration Cranny graphic demonstration system according to claim 9, characterized in that: The gripper mechanism (6) clamps the thin plate (4) through a hard rubber clamping layer (616), and the minimum compression of the rubber indenter should satisfy the following formula: ； in This represents the minimum compression of a single rubber indenter, with dimensions in L. This indicates the mass of the clamped thin plate, with dimensions in meters (m). Represents the vibration frequency, dimensionless: T -1 ; Represents the amplitude of vibration, dimensionless: L; This represents the static friction coefficient between rubber and a thin sheet, and is dimensionless. This indicates the total number of rubber indenters; it is dimensionless. This represents the radial stiffness of a single rubber indenter, with dimensions in M·T. -2 .

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