A sound wave standing wave demonstration device

Abstract

The utility model provides a kind of acoustic standing wave demonstration device, including main control board, air suction pump, vacuum cover and standing wave tube, the utility model is connected with full-frequency loudspeaker electric signal by main control board, realize the accurate adjustment of sound wave frequency / amplitude, the dynamic structural design of being combined with relatively slidable first acrylic pipe and second acrylic pipe, make foam particles form visual sheet-shaped standing wave at wave lobe under the action of sound pressure difference;Standing wave tube is placed in vacuum cover at the same time, and the stability of experimental environment is guaranteed by sealing connection, reduce the interference of sound wave propagation by external air flow and other factors, and the air content in vacuum cover is dynamically regulated by air suction pump, significantly improve the signal-to-noise ratio of experimental environment, finally achieve the core effect that standing wave phenomenon high-definition real-time demonstration and teaching interaction is strong, solve the problem of insufficient standing wave visualization in traditional acoustics teaching.

Description

Technical Field

[0001] This utility model relates to the field of teaching auxiliary equipment technology, and in particular to a sound wave standing wave demonstration device. Background Technology

[0002] A standing wave is a distribution pattern formed along a transmission line by two waves with the same frequency but opposite directions of propagation. One of the waves is usually a reflection of the other, forming antinodes and nodes. On the waveform, the positions of the nodes and antinodes remain unchanged, giving the impression of being stationary.

[0003] In teaching mechanical waves, the phenomenon of standing waves is an important knowledge point. However, traditional teaching methods often rely on theoretical explanations and simple experimental demonstrations, making it difficult for students to intuitively observe the formation and change process of standing waves.

[0004] In view of this, the inventor has designed a sound wave standing wave demonstration device, which leads to this invention. Utility Model Content

[0005] To solve the above problems, the technical solution of this utility model is as follows: A sound wave standing wave demonstration device includes a main control board, a vacuum pump, a vacuum chamber, and a standing wave tube. The main control board is located on the outer wall of the vacuum chamber. The end of the vacuum pump is located inside the vacuum chamber and is sealed to it. The standing wave tube is located inside the vacuum chamber and includes a full-range speaker, a first acrylic tube that can slide relative to each other along the axial direction, and a second acrylic tube connected sequentially from left to right. The first acrylic tube and the second acrylic tube are filled with foam particles. The end of the first acrylic tube is open, and the end of the second acrylic tube away from the first acrylic tube is closed. The main control board is equipped with a sound wave generator, which is electrically connected to the full-range speaker. The main control board is also electrically connected to the vacuum pump and the sound wave generator.

[0006] Preferably, the particle size of the foam particles is 0.5mm-1mm.

[0007] Preferably, the vacuum shroud, the first acrylic tube, and the second acrylic tube are made of transparent material.

[0008] Preferably, both the first acrylic tube and the second acrylic tube have graduations on their outer surfaces.

[0009] Preferably, the main control board is equipped with a sound wave generator, which is electrically connected to the main control board and the full-range speaker.

[0010] Preferably, it also includes a noise detector, which is located on the main control board and electrically connected to the main control board.

[0011] Preferably, the main control board is equipped with a display screen.

[0012] Preferably, the vacuum chamber is provided with a support platform, and the first acrylic tube and the second acrylic tube are located above the support platform.

[0013] Preferably, the main control board is connected to an external power source via a power adapter.

[0014] The technical solution provided by this utility model has the following beneficial effects: This invention achieves precise adjustment of sound wave frequency / amplitude by connecting the main control board to the full-range speaker via electrical signals. Combined with the dynamic structural design of the relatively sliding first and second acrylic tubes, foam particles form a visible sheet-like standing wave at the antinode under the action of sound pressure difference. At the same time, the standing wave tubes are placed in a vacuum chamber, and the sealed connection ensures the stability of the experimental environment, reducing the interference of external air flow and other factors on sound wave propagation. Furthermore, the air content in the vacuum chamber is dynamically controlled by a vacuum pump, which significantly improves the signal-to-noise ratio of the experimental environment. Ultimately, this invention achieves the core effects of high-definition real-time demonstration of standing wave phenomena and strong interactive teaching, solving the problem of insufficient visualization of standing waves in traditional acoustics teaching. Attached Figure Description

[0015] The accompanying drawings, which are provided to further illustrate the present invention and constitute a part of the present invention, illustrate exemplary embodiments of the present invention and are used to explain the present invention, but do not constitute an undue limitation of the present invention.

[0016] in: Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0017] Label Explanation: 1. Main control board; 11. Sound wave generator; 12. Noise detector; 13. Display screen; 2. Air pump; 3. Vacuum chamber; 31. Support platform; 4. Standing wave tube; 41. Full-range speaker; 42. First acrylic tube; 43. Second acrylic tube; 44. Foam particles; 5. Power adapter. Detailed Implementation

[0018] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0019] Please see Figure 1This invention relates to a sound wave standing wave demonstration device, which is the preferred embodiment of the present invention. The device includes a main control board 1, a vacuum pump 2, a vacuum chamber 3, and a standing wave tube 4. The main control board 1 is located on the outer wall of the vacuum chamber 3. The end of the vacuum pump 2 is located inside the vacuum chamber 3 and is sealed to it. The shorter end of the vacuum pump 2 is the suction port, and the longer end is the exhaust port. The suction port is located inside the vacuum chamber 3, and the exhaust port extends out of the vacuum chamber 3, with a sealing ring between it and the vacuum chamber 3 to ensure airtightness. The standing wave tube 4 is located inside the vacuum chamber 3. In traditional teaching methods, students often only understand the standing wave phenomenon through theoretical explanations and simple experiments, but the formation and change process of standing waves is relatively abstract. By setting a standing wave tube 4 inside the vacuum chamber 3 and filling the standing wave tube 4 with foam particles 44, when the full-range speaker 41 operates and generates sound waves, forming a standing wave inside the standing wave tube 4, the foam particles 44 will exhibit different states at the nodes and antinodes. This visual difference allows students to intuitively observe the positions of the antinodes (where the particle amplitude is larger) and nodes (where the particle is almost stationary) of the standing wave, as well as their changes during the formation of the standing wave. The standing wave tube 4 includes a full-range speaker 41, a first acrylic tube 42 and a second acrylic tube 43 that can slide relative to each other along the axial direction, connected sequentially from left to right. The first acrylic tube 42 and the second acrylic tube 43 are filled with foam particles 44. The flexibility of this structure allows teachers or experimenters to easily adjust the length of the standing wave tube 4. By changing the tube length, the formation conditions and characteristics of standing waves at different wavelengths can be studied. The main control board 1 is electrically connected to the air pump 2 and the full-range speaker 41. Since the entire standing wave tube 4 is placed inside the vacuum chamber 3 and the sealed connection ensures the stability of the experimental environment. In a vacuum environment, the propagation of sound waves is less affected by factors such as external airflow, making the formation of standing waves more stable. Moreover, each experiment can be conducted under the same initial conditions, allowing teachers or experimenters to precisely control the air pressure environment inside the vacuum chamber 3 during the experiment. By adjusting the operation of the vacuum pump 2, the air pressure inside the vacuum chamber 3 can be changed, thereby affecting parameters such as the propagation speed and wavelength of sound waves in the standing wave tube 4, and also reducing noise. At the same time, the main control board 1 can easily change the frequency of the sound waves by controlling the full-range speaker 41, thus simulating the formation of standing waves under different conditions, providing convenience for studying the characteristics of standing waves in different environments.

[0020] Please refer to Figure 1The foam particles 44 have a particle size of 0.5mm-1mm. These are lightweight foam particles, and in this embodiment, the diameter of the foam particles 44 is 1mm. The smaller particle size allows the smaller foam particles 44 to respond more sensitively to changes in sound pressure when acted upon by sound waves within the standing wave tube 4. At the antinodes, where sound pressure changes are more drastic, the smaller particles exhibit stronger vibrations more clearly, and the dynamic changes in aggregation and dispersion are more clearly visible. At the nodes, where sound pressure is relatively stable, the almost motionless state of the particles can be more accurately represented. This helps students visually observe the positions of antinodes and nodes, as well as the changes in the standing wave. Simultaneously, the smaller particle size allows the particles to fill each other, reducing gaps and thus better interacting with sound waves.

[0021] Please refer to Figure 1 The vacuum chamber 3, the first acrylic tube 42, and the second acrylic tube 43 are made of transparent material. The transparency makes the entire experimental process clear at a glance. Students can directly see the structure of the standing wave tube 4 inside the vacuum chamber 3, observe the movement of the foam particles 44 in the standing wave tube 4, and the positions of the antinodes and nodes. This allows them to observe the formation and change of the standing wave from all angles without having to indirectly infer the state of the standing wave through other complex measuring equipment. It also facilitates inspection and maintenance.

[0022] For details, please refer to Figure 1 Both the first acrylic tube 42 and the second acrylic tube 43 have graduations on their outer surfaces, allowing for easy reading of their lengths and the distance between adjacent antinodes of the standing wave. During experiments, when studying the formation of standing waves at different tube lengths, the change in tube length can be accurately determined simply by observing the graduations. This facilitates quantitative analysis. Furthermore, the graduations help experimenters precisely control the change in tube length when adjusting the length of the standing wave tube 4. For example, to change the tube length by 5 cm, the experimenter can quickly and accurately move the acrylic tube to the corresponding position using the graduations, thereby improving experimental accuracy, facilitating the investigation of standing wave formation conditions, and easily measuring sound velocity.

[0023] The specific steps for investigating the conditions for standing wave formation are as follows: 1. Fix the sound frequency, change the length of the acrylic tube multiple times to create a standing wave inside the tube, and record the corresponding data; 2. Change the sound frequency, fix the length of the acrylic tube, create a standing wave inside the tube, and record the corresponding data; The wavelength λ was calculated by measuring the distance d between adjacent antinodes multiple times, and the ratio n of the tube length L to a quarter wavelength was also calculated. It was observed that the ratio of the tube length to a quarter wavelength calculated under all experimental conditions was close to an odd integer, successfully verifying that the necessary condition for forming a stable standing wave in a standing wave tube fixed at both ends is that the tube length must be an odd integer multiple of a quarter wavelength of the sound wave, that is, satisfying the relationship: where n is a positive integer (1,3,5,).

[0024] The specific steps for measuring the speed of sound are as follows: 1. Fix the sound frequency, change the length of the acrylic tube multiple times to create a standing wave inside the tube, and record the corresponding data; 2. Change the sound frequency, fix the length of the acrylic tube, create a standing wave inside the tube, and record the corresponding data; A sound wave signal of a specified frequency is output by the main control board 1 and amplified by the full-range speaker 41 to generate an incident sound wave. During propagation, the incident sound wave is reflected, and the reflected wave superimposes on the incident wave. When an integer multiple of 1 / 4 of the sound wave wavelength equals the length of the standing wave tube 4, a standing wave is generated inside the tube. Under the influence of the sound wave, the foam particles 44 are pushed from the nodes (high sound pressure) region of the standing wave to the antinodes (low sound pressure) region, concentrating in the antinode region to form a distinct sheet-like distribution structure. This allows for visualization of the sound wave and measurement of the distance between adjacent antinodes. The wavelength of the sound wave is obtained. Calculate the speed of sound And to achieve the goal of exploring the formation and propagation of waves.

[0025] For details, please refer to Figure 1 The main control board 1 is equipped with a sound wave generator 11, which is electrically connected to the main control board 1 and the full-range speaker 41. The sound wave generator 11 can typically generate sound waves of a specific frequency, and the frequency can be precisely adjusted. Combined with the control functions of the main control board 1, precise control of the sound wave frequency can be achieved, thereby enabling the study of the formation conditions and characteristics of standing waves at different frequencies. During the experiment, the full-range speaker 41 and the sound wave generator 11 can be controlled as needed. For example, the sound wave generator 11 outputs an electrical signal, which is then amplified by the full-range speaker 41 to generate a basic sound wave standing wave. The main control board 1 then controls the sound wave generator 11 to emit a sound wave of a specific frequency, and the changes in the standing wave under the interaction of the two are observed. This ability to dynamically adjust the sound wave parameters is helpful for studying complex sound wave interaction phenomena.

[0026] For details, please refer to Figure 1The system also includes a noise detector 12, which is mounted on and electrically connected to the main control board 1. The noise detector 12 can monitor the noise level in the experimental environment in real time, including the sound waves generated by the full-range speaker 41 and the sound wave generator 11, as well as external environmental noise. This helps teachers and students understand changes in the acoustic environment during the experiment, ensuring that the experiment is conducted within a controllable noise range. When excessive environmental noise is detected, measures can be taken to reduce interference, such as adjusting the operating parameters of the experimental equipment or improving the experimental environment. This helps improve the accuracy and reliability of the experiment, avoiding interference from external noise on the standing wave experiment. Furthermore, if the sound wave intensity generated by the full-range speaker 41 or the sound wave generator 11 is too high during the experiment, it may damage the hearing of the experimenters. The noise detector 12 can monitor the sound wave intensity in real time. When the sound intensity exceeds a safe threshold, the main control board 1 can adjust or shut down the sound wave generator in a timely manner, effectively protecting students' hearing. The monitoring data from the noise detector 12 can be fed back to the main control board 1 and presented to teachers and students through the main control board 1's display or other output methods.

[0027] For details, please refer to Figure 1 The main control board 1 is equipped with a display screen 13, which uses an OLED display device to display key information such as the waveform, frequency, and amplitude of the standing wave in real time, providing students with an intuitive visual experience. Combined with the movement state of the foam particles 44 inside the standing wave tube 4, the display screen 13 can further assist in presenting relevant information about the standing wave phenomenon.

[0028] For details, please refer to Figure 1 The vacuum chamber 3 contains a support platform 31, above which the first acrylic tube 42 and the second acrylic tube 43 are positioned. The support platform 31 provides a stable foundation for the first acrylic tube 42 and the second acrylic tube 43. During the experiment, when the full-range speaker 41 emits sound waves, the foam particles 44 inside the standing wave tube 4 vibrate, and the tube may experience a certain reaction force and shake. The support platform 31 can effectively reduce this shaking, ensuring that the standing wave tube 4 remains stable during the experiment, thereby improving the reliability and accuracy of the experiment. The support platform 31 also ensures that the first acrylic tube 42 and the second acrylic tube 43 are evenly stressed, avoiding deformation or damage caused by uneven stress. This is crucial for ensuring the shape and performance of the standing wave tube 4, especially during multiple experiments or adjustments to the tube length, ensuring the integrity of the tube.

[0029] For details, please refer to Figure 1The main control board 1 is connected to an external power source via power adapter 5. Power adapter 5 converts the voltage and current of the external power source into a stable power supply suitable for the main control board 1 and other devices (such as the full-range speaker 41, sound wave generator 11, etc.). This ensures that the equipment can operate continuously and stably during the experiment, avoiding interruptions due to power fluctuations. Through power adapter 5, the input power supply can be filtered and regulated, reducing the impact of noise interference and voltage fluctuations in the external power supply on the experimental equipment. This helps improve the performance and measurement accuracy of the experimental equipment, making the experimental results more accurate and reliable.

[0030] In summary, this invention achieves precise adjustment of sound wave frequency / amplitude by electrically connecting the main control board 1 to the full-range speaker 41. Combined with the dynamic structural design of the relatively sliding first acrylic tube 42 and the second acrylic tube 43, the foam particles 44 form a visible sheet-like standing wave at the antinode under the action of sound pressure difference. At the same time, the standing wave tube 4 is placed inside the vacuum chamber 3, and the sealed connection ensures the stability of the experimental environment, reducing the interference of external air flow and other factors on sound wave propagation. Furthermore, the air pump 2 dynamically regulates the air content inside the vacuum chamber 3, significantly improving the signal-to-noise ratio of the experimental environment. Ultimately, this invention achieves the core effects of high-definition real-time demonstration of standing wave phenomena and strong interactive teaching, solving the problem of insufficient visualization of standing waves in traditional acoustics teaching.

[0031] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A sound wave standing wave demonstration apparatus, characterized by, The system includes a main control board (1), a vacuum pump (2), a vacuum chamber (3), and a standing wave tube (4). The main control board (1) is located on the outer wall of the vacuum chamber (3). The end of the vacuum pump (2) is located inside the vacuum chamber (3) and is sealed to it. The standing wave tube (4) is located inside the vacuum chamber (3). The standing wave tube (4) includes a full-range speaker (41), a first acrylic tube (42), and a second acrylic tube (43) that can slide relative to each other along the axial direction, connected sequentially from left to right. The first acrylic tube (42) and the second acrylic tube (43) are filled with foam particles (44). The first acrylic tube (42) is open at one end, and the second acrylic tube (43) is closed at the end away from the first acrylic tube (42). The main control board (1) is equipped with a sound wave generator (11). The sound wave generator (11) is electrically connected to the full-range speaker (41). The main control board (1) is electrically connected to the air pump (2) and the sound wave generator (11).

2. A sound wave standing wave demonstration apparatus according to claim 1, wherein, The particle size of the foam particles (44) is 0.5 mm to 1 mm.

3. The acoustic standing wave demonstration apparatus of claim 1, wherein, The vacuum cover (3), the first acrylic tube (42) and the second acrylic tube (43) are made of transparent material.

4. The acoustic standing wave demonstration apparatus of claim 1, wherein, The outer surfaces of the first acrylic tube (42) and the second acrylic tube (43) are both provided with scales.

5. The acoustic standing wave demonstration apparatus of claim 1, wherein, It also includes a noise detector (12), which is located on the main control board (1) and is electrically connected to the main control board (1).

6. The acoustic standing wave demonstration apparatus of claim 1, wherein, The main control board (1) is equipped with a display screen (13).

7. The acoustic standing wave demonstration apparatus of claim 1, wherein, The vacuum hood (3) is provided with a support platform (31) inside, and the first acrylic tube (42) and the second acrylic tube (43) are located above the support platform (31).

8. The acoustic standing wave demonstration apparatus of claim 1, wherein, The main control board (1) is connected to an external power source via a power adapter (5).

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