The instrument is a patented product of our company. It is easy to carry and move, reliable in performance and easy to operate. It can comprehensively test the ultrasonic transducer system (transducer, horn, ultrasonic mold). I. Equipment Introduction The main parameters of piezoelectric ultrasonic transducer are series resonant frequency (mechanical resonant frequency) fs, parallel resonant frequency (anti-resonant frequency) fp, series resonant impedance (mechanical resonant impedance) Ro, parallel resonant impedance (reverse Resonant impedance) Rp, free capacitance Co, etc. There are two general test methods. One is the constant voltage source transmission line method, which has low equipment requirements and simple test principle, but
The piezoelectric impedance tester manufactured by our company is portable, portable and easy to operate. It can measure the ultrasonic transducer system (transducer, horn, ultrasonic mould) comprehensively.
I. Brief Introduction of Equipment
The main parameters of piezoelectric ultrasonic transducer are series resonance frequency (mechanical resonance frequency) fs, parallel resonance frequency (anti-resonance frequency) fp, series resonance impedance (mechanical resonance impedance) Ro, parallel resonance impedance (anti-resonance impedance) Rp, free capacitance Co, etc. There are two kinds of conventional testing methods. One is the constant voltage source transmission line method, which requires low equipment and simple testing principle, but the testing speed is slow and the accuracy is poor. It also relies on the larger signal source, oscilloscope, millivoltmeter and other general instruments to operate manually. The other is the impedance analyzer. This method can realize automatic testing with relatively high speed. Fast, but the equipment is huge, expensive, and some still need to rely on computers, which makes it inconvenient to carry. According to the above situation, our company has developed a portable ultrasonic transducer tester. The equipment adopts admittance circle analysis principle, interpolation algorithm to extract data, automatic testing, fast speed, high accuracy, small size, light weight, portable, practical, mainly used for conventional production guidance and equipment maintenance and debugging on site.
II. Working Principle
The core component of the instrument is the impedance measurement core produced by ADI company. The frequency generator with 12 bits and 1 MSPS AD converter is integrated in the instrument. This frequency generator can generate a specific frequency to excite the transducer under test. The response signal of the transducer under test is sampled by ADC, and discrete Fourier transform is performed by DSP on chip. After Fourier transform, the real part R and imaginary part I of the transducer under test are returned to the output frequency. The real part R and imaginary part I of the transducer under test are measured continuously in one frequency band. The impedance transformation admittance circle of the transducer under test can be drawn. The basic parameters of the transducer under test can be obtained by analyzing the admittance circle.
III. Equipment parameters
1. Power supply: AC160V~250V.
2. Power consumption: less than 5W
3. Volume: 80 mm high, 205 mm wide and 230 mm long
4. Weight: 800g
IV. Content, Range and Accuracy of Measurement Parameters
1. Fs: Series resonance frequency (mechanical resonance frequency), that is, the natural working frequency of the vibration system. The measuring range of this parameter is 1 Hz ~ 999999 hz, the measuring precision is 0.01 Hz and the display precision is 1 hz.
2. Fp: Parallel resonant frequency (anti-resonant frequency), i.e. the resonant frequency of parallel branch of piezoelectric oscillator. The measuring range of this parameter is 1 hz~999999 hz, the measuring precision is 0.01 hz, and the display precision is 1 hz.
3. Ro: Series resonance impedance (mechanical resonance impedance), mechanical resonance frequency, piezoelectric device impedance, showing pure resistance. The measuring range of this parameter is from 0.01 ohm to 9999.99 ohm, the measuring precision is 0.01 ohm and the display precision is 0.01 ohm.
4. Rp: Parallel resonant impedance (anti-resonant impedance), the impedance of piezoelectric devices at anti-resonant frequency. The measuring range of this parameter is from 0.01K ohm to 9999.99k ohm, the measuring precision is 0.01K ohm and the display precision is 0.01K ohm.
5. Co: Free capacitor. The measuring range of this parameter is 0.01nF~9999.99nF, the measuring precision is 0.01 nF and the display precision is 0.01 nF.
V. Equipment Application
This tester is mainly used for routine production guidance of ultrasonic equipment and on-site maintenance and debugging of equipment. It can also be used to evaluate the performance of piezoelectric devices, such as piezoelectric ceramic, piezoelectric transducer, resonator, buzzer, ultrasonic sensor, transducer, horn and die assembly. Examples of specific applications are as follows:
1. In the production of ultrasonic cleaner, the resonant frequency consistency of the oscillator is tested, the performance of the oscillator box or plate is controlled, the overall parameters of the oscillator box or plate are tested, and the matching power supply is selected.
2. In the production of ultrasonic welding machine, guide the design and production of horn or die to match the horn or die with transducer.
3. In the production of transducers, piezoelectric ceramics are selected.
4. In the field maintenance, judge the fault of the ultrasonic vibration system.
5. Provide scientific test data during the test or trial-manufacture of power ultrasound products.
6. Scientific research on piezoelectric devices.