5.5 Study on Optimization of Parameters of Measuring Path …
409
15–50 and 100–2000 Hz with the amplitude that provide maximal amplitude of the
diffusive surface of the vibrator 5 not more than 5 μm.
On each of the set frequencies of the calibrated vibrator, the registration and
processing of the measuring signal were conducted with the laser specklometer and
a computer and the f 0 value was determined. The calculation of the error of the
measured frequency value f 0 from the frequency of the calibrated vibrator f k showed
that the relative error of measurement of vibration frequency in the range of 15–50
Hz did not exceed 4% and in the range of 100–2000 Hz was not more than 1.5%.
5.5.2 Study of Longitudinal Component Amplitude
of Vibration of a Microinstrument of the Ultrasonic
Welding System
The developed prototype of the laser specklometer gives the possibility to measure
the longitudinal component of vibration of diffusive components that is of great
importance for many tasks of vibrometry. Measurement of oscillation amplitude of
details and units of aircraft engines, for example, of turbine buckets, with the laser
interferometry method during their fatigue tests gives the possibility to study the
vibration characteristics of the test specimens rather effectively: to determine the
values of resonance frequencies, the beginning of product distortion according to
changes of the longitudinal vibration amplitude.
Ultrasonic welding is one of the most widespread technological operations
during assembling of products of electronic technology (integral schemes, hybrid
microassemblies, etc.). Provision with high quality of connections during velocity
welding on semiautomatic and automatic installations requires high accuracy of
maintenance of parameters of the welding process. Load effort, welding time and
oscillation amplitude of the microinstrument are the main parameters of the ultrasonic
welding. But the greatest complication is the calibration and control of microinstrument oscillation amplitude during welding, and characteristics of the USWS
(ultrasonic welding system) influence greatly its level.
Piezoceramic and magnetic pickups and capacitive microphones, which are
applied for measurements of oscillation amplitude of the ultrasonic converters, are
contactless and sensitive to background impacts in working conditions that does not
provide sufficient accuracy and spatial distribution during measurements, and that is
why they are not effective enough for calibration and control of the USWS.
Application of laser interferometers gives the possibility to avoid the abovementioned disadvantages, but using them for control of USWS oscillation amplitude
requires additional treatment of the surface of the instrument to make it a specular
reflective one.
The presented laser Doppler vibrometer gives the possibility to make measurements of the USWS oscillation amplitude without preliminary treatment of the instrument. But the presence of angular or transverse vibration components can lead to
409
15–50 and 100–2000 Hz with the amplitude that provide maximal amplitude of the
diffusive surface of the vibrator 5 not more than 5 μm.
On each of the set frequencies of the calibrated vibrator, the registration and
processing of the measuring signal were conducted with the laser specklometer and
a computer and the f 0 value was determined. The calculation of the error of the
measured frequency value f 0 from the frequency of the calibrated vibrator f k showed
that the relative error of measurement of vibration frequency in the range of 15–50
Hz did not exceed 4% and in the range of 100–2000 Hz was not more than 1.5%.
5.5.2 Study of Longitudinal Component Amplitude
of Vibration of a Microinstrument of the Ultrasonic
Welding System
The developed prototype of the laser specklometer gives the possibility to measure
the longitudinal component of vibration of diffusive components that is of great
importance for many tasks of vibrometry. Measurement of oscillation amplitude of
details and units of aircraft engines, for example, of turbine buckets, with the laser
interferometry method during their fatigue tests gives the possibility to study the
vibration characteristics of the test specimens rather effectively: to determine the
values of resonance frequencies, the beginning of product distortion according to
changes of the longitudinal vibration amplitude.
Ultrasonic welding is one of the most widespread technological operations
during assembling of products of electronic technology (integral schemes, hybrid
microassemblies, etc.). Provision with high quality of connections during velocity
welding on semiautomatic and automatic installations requires high accuracy of
maintenance of parameters of the welding process. Load effort, welding time and
oscillation amplitude of the microinstrument are the main parameters of the ultrasonic
welding. But the greatest complication is the calibration and control of microinstrument oscillation amplitude during welding, and characteristics of the USWS
(ultrasonic welding system) influence greatly its level.
Piezoceramic and magnetic pickups and capacitive microphones, which are
applied for measurements of oscillation amplitude of the ultrasonic converters, are
contactless and sensitive to background impacts in working conditions that does not
provide sufficient accuracy and spatial distribution during measurements, and that is
why they are not effective enough for calibration and control of the USWS.
Application of laser interferometers gives the possibility to avoid the abovementioned disadvantages, but using them for control of USWS oscillation amplitude
requires additional treatment of the surface of the instrument to make it a specular
reflective one.
The presented laser Doppler vibrometer gives the possibility to make measurements of the USWS oscillation amplitude without preliminary treatment of the instrument. But the presence of angular or transverse vibration components can lead to