Portable experiment demonstration teaching device for measuring inherent frequency of object

Abstract

The utility model discloses a portable experiment demonstration teaching device for measuring the inherent frequency of an object, and the device comprises a pedestal, a sound box which is disposed on the pedestal and is used for outputting a sound wave signal, and a sound collection frame. The beneficial effects are that a cooperative reflection structure of the sound collection rack and the sound gathering rack is additionally arranged so that directional reflection and energy focusing can be carried out on multi-frequency sound waves emitted by the sound box, sound wave energy is enabled to act on the surface of a measured object more densely, the amplitude response speed of the measured object in a resonance state is enabled to be increased by improving sound energy transmission efficiency, and the sound quality of the measured object is improved. And meanwhile, environmental noise interference is effectively inhibited, the signal-to-noise ratio of signals is improved, the time consumed for capturing the resonance peak value by the oscilloscope is shortened, and rapid locking of the inherent frequency is realized in cooperation with the real-time frequency regulation and control function of the smart phone APP, so that the experiment time is effectively shortened, the experiment precision is improved, and demonstration teaching is facilitated.

Description

Technical Field

[0001] This utility model relates to the technical field of experimental devices for measuring the natural frequency of objects, and in particular to a portable experimental demonstration and teaching device for measuring the natural frequency of objects. Background Technology

[0002] In physics experiment teaching, measuring the natural frequency of an object is a fundamental and important experimental topic. Currently, a common experimental method for measuring the natural frequency of an object is to use a speaker to emit sounds of different frequencies, which cause local air vibrations, thereby causing the object under test to vibrate, thus providing the driving force for the experiment. When the frequency of the driving force is close to or equal to the natural frequency of the object, the object will resonate. At this point, the natural frequency of the object can be detected based on the resonance state.

[0003] However, this speaker-based experimental method has significant shortcomings. Because sound emitted from a speaker is diffuse, it disperses in all directions during propagation, making it difficult to concentrate on the object being tested. This characteristic results in a large amount of sound energy being wasted in ineffective spatial propagation during the experiment, significantly reducing the effective sound energy acting on the object. Furthermore, the sound energy received by the object at different locations varies considerably, which is undoubtedly a serious obstacle for teaching work that requires precise measurements and stable experimental results.

[0004] Therefore, developing a portable experimental demonstration and teaching device that can effectively concentrate acoustic energy onto the object being measured to measure its natural frequency is of great practical significance. Utility Model Content

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0006] In view of the problems of the above-mentioned portable experimental demonstration and teaching device for measuring the natural frequency of an object, this utility model is proposed.

[0007] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a portable experimental demonstration and teaching device for measuring the natural frequency of an object, including a base;

[0008] The speaker, mounted on the base, is used to output sound wave signals;

[0009] A sound collector, shaped like a trumpet, is fitted around the sound-producing part of the speaker to perform the initial reflection of sound waves and suppress lateral diffusion.

[0010] The sound focusing frame is a semi-open sphere, which is coaxially arranged opposite to the sound collecting frame, and the inner diameter of the open end is larger than the inner diameter of the open end of the sound collecting frame. It is used to reflect sound waves a second time to form a sound energy focusing area.

[0011] The object to be tested is placed on the base and is located in the sound energy focusing area.

[0012] As a preferred embodiment of the portable experimental demonstration and teaching device for measuring the natural frequency of an object according to the present invention, the sound collection frame includes a reflector and a sound-absorbing cover, wherein the sound-absorbing cover is attached to the outer surface of the reflector.

[0013] As a preferred embodiment of the portable experimental demonstration and teaching device for measuring the natural frequency of an object according to the present invention, the sound-gathering frame includes a second reflector and a second sound-absorbing cover, wherein the second sound-absorbing cover is attached to the outer surface of the second reflector.

[0014] As a preferred embodiment of the portable experimental demonstration and teaching device for measuring the natural frequency of an object according to the present invention, the reflector is composed of a double-layer shell, and a soundproof cavity is provided between the double-layer shell.

[0015] As a preferred embodiment of the portable experimental demonstration and teaching device for measuring the natural frequency of an object according to this utility model, both the first reflector and the second reflector are made of aluminum alloy, and both the first sound-absorbing cover and the second sound-absorbing cover are made of sound-absorbing sponge.

[0016] As a preferred embodiment of the portable experimental demonstration and teaching device for measuring the natural frequency of an object according to the present invention, wherein: an oscilloscope is provided on the base, and the oscilloscope is electrically connected to a piezoelectric ceramic plate via a BNC double-wire alligator clip, the piezoelectric ceramic plate is attached to the surface of the object to be measured, and is used to convert the vibration signal into an electrical signal and transmit it to the waveform detection area of ​​the oscilloscope.

[0017] The beneficial effects of this invention are as follows: By adding a synergistic reflection structure of a sound collector and a sound focuser, the multi-frequency sound waves emitted by the speaker can be directionally reflected and focused, allowing the sound wave energy to act more densely on the surface of the object being tested. By improving the sound energy transmission efficiency, the amplitude response speed of the object under test in the resonant state is increased, while effectively suppressing environmental noise interference. The time required for the oscilloscope to capture the resonant peak is shortened, and with the real-time frequency control function of a smartphone APP, the natural frequency can be quickly locked, thereby effectively shortening the experimental time and improving experimental accuracy, which is beneficial for demonstration and teaching. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them:

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] Figure 2 This is a side view of the speaker, the sound frame, and the object to be tested in this utility model.

[0021] Figure 3 This is a side view of the present invention.

[0022] Figure 4 This is a schematic diagram of the structure of the object to be tested in this utility model.

[0023] Figure descriptions: 1. Base; 2. Speaker; 3. Speaker housing; 31. Reflector 1; 32. Sound absorber 1; 4. Sound focusing frame; 41. Reflector 2; 42. Sound absorber 2; 5. Object under test; 6. Oscilloscope; 7. Piezoelectric ceramic plate. Detailed Implementation

[0024] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0026] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.

[0027] Secondly, this utility model is described in detail with reference to the schematic diagrams. When describing the embodiments of this utility model, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. In addition, actual manufacturing should include the three-dimensional spatial dimensions of length, width, and depth.

[0028] Reference Figures 1-4 This invention provides a portable experimental demonstration and teaching device for measuring the natural frequency of an object, comprising a base 1, which is the basic support part of the entire device. It provides a stable mounting platform for other components, ensuring that the positions of each component are fixed during the experiment and avoiding the influence of factors such as shaking on the measurement results.

[0029] like Figures 2-3 As shown, the speaker 2, mounted on the base 1, outputs sound wave signals as an excitation source in the experiment, providing driving force for the vibration of the object. It connects to a mobile phone via Bluetooth or a USB data cable, and the sound wave frequency can be continuously changed through a mobile app (such as Sonic software). By adjusting the frequency, the waveform on the oscilloscope 6 is observed to find the approximate natural frequency range. Fine adjustments are then made based on this frequency range, readings are taken, and specific values ​​are determined.

[0030] The sound collector 3, in the shape of a trumpet, is fitted around the sound-producing part of the speaker 2 to perform the initial reflection of sound waves and suppress lateral diffusion;

[0031] The sound collector 4 is a semi-open sphere, which is coaxially arranged opposite to the sound collector 3, and the inner diameter of the open end is larger than the inner diameter of the open end of the sound collector 3. It is used to reflect the sound waves twice to form a sound energy focusing area.

[0032] The sound collector 3 includes a reflector 31 and a sound absorber 32, with the sound absorber 32 attached to the outer surface of the reflector 31.

[0033] The sound-collecting frame 4 includes a second reflector 41 and a second sound-absorbing cover 42. The second sound-absorbing cover 42 is attached to the outer surface of the second reflector 41. The second reflector 41 is composed of a double-layer shell, and there is a sound-insulating cavity between the double-layer shell to block external noise interference and ensure the acoustic purity of the experimental environment.

[0034] Both reflector 1 (31) and reflector 2 (41) are made of aluminum alloy. Utilizing the excellent reflective properties of aluminum alloy, the sound waves emitted by speaker 2 are initially reflected, concentrating the sound waves to propagate in a specific direction. Both sound-absorbing cover 1 (32) and sound-absorbing cover 2 (42) are made of sound-absorbing sponge, which can effectively absorb excess sound wave energy on the outer surface of reflector 1 (31) and reflector 2 (41), suppress the lateral diffusion of sound waves, and allow more sound wave energy to propagate in the predetermined direction. This enhances the directionality and concentration of sound wave propagation, improves the utilization efficiency of sound wave energy in the experiment, and enhances the sound energy focusing effect.

[0035] The object to be tested, 5, can be a beaker or a graduated cylinder, etc., placed on the base 1 and in the sound energy focusing area. This position setting allows the object to be tested, 5, to fully receive the focused sound wave energy, making it easier to induce resonance and improve the accuracy of natural frequency measurement and the sensitivity of the experiment.

[0036] An oscilloscope 6 is mounted on the base 1. The oscilloscope 6 is electrically connected to a piezoelectric ceramic plate 7 via BNC alligator clips. The piezoelectric ceramic plate 7 is attached to the surface of the object under test 5. When the object under test 5 vibrates under acoustic excitation, the piezoelectric ceramic plate 7 converts the vibration signal into an electrical signal, which is then transmitted to the waveform detection area of ​​the oscilloscope 6 via the BNC alligator clips. The oscilloscope 6 can visually display the waveform of the electrical signal. By observing the waveform changes, the experimenter can accurately record relevant data about the object's vibration, thereby determining the object's natural frequency.

[0037] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A portable experimental demonstration teaching device for measuring the natural frequency of an object, characterized in that, It includes: Base (1); Sound (2), set in the base (1), for outputting acoustic signal; Collecting frame (3), trumpet-shaped, set in the sound (2) sound part of the outer periphery, for the first reflection of sound waves and inhibit lateral diffusion; Sound collecting frame (4), for half-open sphere, which is coaxially arranged with the collecting frame (3) opposite, and the opening end inner diameter is greater than the opening end inner diameter of the collecting frame (3), for the second reflection of sound waves, forming a sound energy focusing area; The object to be measured (5) is placed on the base (1), and is in the sound energy focusing area.

2. The experimental demonstration teaching device for measuring the natural frequency of an object according to claim 1, characterized in that: The collecting frame (3) includes a reflection cover (31) and a sound absorbing cover (32), and the sound absorbing cover (32) is attached to the outer surface of the reflection cover (31).

3. The experimental demonstration teaching device for measuring the natural frequency of an object according to claim 2, characterized in that: The sound collecting frame (4) includes a reflection cover (41) and a sound absorbing cover (42), and the sound absorbing cover (42) is attached to the outer surface of the reflection cover (41).

4. The experimental demonstration teaching device for measuring the natural frequency of an object according to claim 3, characterized in that: The reflection cover (41) is composed of double-layer shell, and the double-layer shell has a sound insulation cavity.

5. The experimental demonstration teaching device for measuring the natural frequency of an object according to claim 4, characterized in that: The reflection cover (31) and the reflection cover (41) are made of aluminum alloy material, and the sound absorbing cover (32) and the sound absorbing cover (42) are made of sound absorbing sponge material.

6. The experimental demonstration teaching device for measuring the natural frequency of an object according to claim 1, characterized in that: The base (1) is provided with an oscilloscope (6), the oscilloscope (6) is electrically connected with a piezoelectric ceramic sheet (7) through a BNC double-wire alligator clip, the piezoelectric ceramic sheet (7) is pasted on the surface of the object to be measured (5), for converting vibration signal into electric signal and transmitting to the waveform detection area of the oscilloscope (6).

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