A tuning fork is a "Y" shaped steel or aluminum alloy sounder. Various tuning forks can emit pure tones of different frequencies when vibrating due to their different masses, lengths and thicknesses of the fork arms.
The tuning fork was invented by Englishman John Shore in 1711. He was a court trumpeter, and composers Georg Friedrich Handel and Henry Purcell both wrote passages in their music specifically for his performance. He was also a lute player. The lute was very difficult to tune. Scholl invented the tuning fork to tune the lute.
1. The use of tuning forks in teaching
In teaching, tuning forks can be used to demonstrate vibration. Strike the tuning fork to collect the sound waveform. The test found that:
1. When the tuning fork is tapped lightly, the amplitude of the tuning fork is small, and the amplitude of the waveform is small. At this time, the sound emitted by the tuning fork is also small;
2. When the tuning fork is tapped hard, the amplitude of the tuning fork is small. The amplitude is large, the amplitude of the waveform is large, and the sound produced by the tuning fork is also loud.
3. Explanation: Loudness is related to the amplitude of the tuning fork vibration. The larger the amplitude, the louder the loudness; the smaller the amplitude, the smaller the loudness.
2. The use of tuning forks in medical examinations
The tuning fork examination is a simple and reliable common diagnostic method for identifying the nature of deafness - conductive deafness or sensorineural deafness. Check the method. Tuning forks are also used to test a patient's hearing. The most commonly used tuning fork is C-512. Lower frequency tuning forks (usually C-128) also serve as a test of peripheral nervous system sensitivity to vibration. Tuning forks are also used as therapeutic tools in some special therapies such as sonopuncture. John Beaulieu studied the therapeutic effects of tuning forks and recorded an album of music called "Calendula", in which all music was performed using tuning forks. Others, such as Arden Wicken and Jack Wicken, are also researchers on the efficacy of tuning forks.
3. The use of tuning forks in the piano tuning process
Using tuning forks to obtain the "standard tone" is one of the most important steps in the piano tuning process. Its importance lies in the pitch position of each key of a piano.
Tuning forks are primarily used for tuning musical instruments, although electronic tuners now exist and some musicians have absolute pitch. When the tuning fork needs to be tuned, adjustments can be made to the bifurcated parts at both ends: shorten the tip part to increase the frequency or trim the joint between the two forks to decrease the frequency; or adjust the weight of the two tines. Even after tuning, the frequency of the tuning fork will still be affected by the change in the elastic modulus of the material. In order for the tuning fork to emit accurate pitch, it should still be stored in a place with good temperature and humidity control. Large tuning forks are usually powered by electricity, like an electric bell, so they vibrate continuously.
IV. Industrial use
The tuning fork level meter is a switch that controls the level. When working, the tuning fork is constantly vibrating. When an object hits the tuning fork, the vibration will be destroyed. Resonance, there is a current output in the circuit, which outputs the excitation current, and then there is a feedback. When the vibration is destroyed, the circuit will recognize it, and then it can output a switching signal, which is a relay signal. The vibration frequency of the tuning fork is at a frequency of 300HZ plus or minus 50hz.
Extended information:
The tuning fork currently most commonly used by musicians has a frequency of 440Hz. This pitch has long been used as the tuning standard for orchestras because it is the pitch of the second string of the violin and an octave higher than the first string of the viola and cello. However, there are also tuning forks with various other pitches on the market, such as those that produce all the pitches of the reference group in the center of the piano.
The notes emitted by the tuning fork after being struck are very weak and can only be heard clearly when it is held to the ear. For this reason, the tuning fork is sometimes pressed against a solid surface such as a table after being struck. This allows the surface to act as a vibrating plate, greatly increasing the volume.
Famous tuning fork manufacturers such as Ragg and John Walker, both located in Sheffield, England.
Reference: Baidu Encyclopedia-Tuning Fork