TRZ Ultrasonic Horn Analyzer
The TRZ Horn Analyzer has a wide range of applications, ranging from the quality control of transducers for medical and dental applications up to sonotrodes for cutting and welding of polymeric materials.
The TRZ is also used in received equipment inspection by companies that have a large number of ultrasonic welding or cut machines, to prevent the production line stoppages due to non-compliant spare parts.
Testing and Quality Control of Transducers
The quality control of ultrasonic transducers is performed by the characterization of their frequency and their impedance of operation. To be approved, these parameters must be within acceptable ranges. For example, a transducer (otherwise called a converter) of 20 kHz for ultrasonic welding, should have a frequency of 20,500 Hz with a tolerance of ± 50 Hz, i.e, to show a frequency between 20,450 and 20,550 Hz, and an impedance of at least 30 kΩ.
Deviations indicate problems in the parts manufacturing and / or assemblage and must be meticulously evaluated to avoid future problems of low performance and technical assistance. A transducer with characteristics outside these ranges can operate, but with low performance, overheating, and reduced work life - besides the risk of damage to the generator and associated items such as sonotrodes and boosters.
When a transducer has non-compliance, it can be recovered by identifying and correcting the problem. Typical causes are dimensional deviations (frequency change) and assembly failures(impedance change).
The acceptance intervals are determined from the characterization of the average values and deviations of a pilot batch of reference transducers. When necessary, the ATCP can offer a customized consultation to assist the determination of acceptance intervals.
The ATCP offers a printer to register the test results in a self-adhesive label attachable to the item tested, and software that applies the acceptance criteria and automatically generates a PDF report of the result as optional items.
The transducers used in dental scalers and ultrasonic scalpels are other examples of transducers for which the quality control is very important.
Tuning of Sonotrodes
The sonotrodes and/or tools for ultrasonic welding and cutting are items that require a perfect tuning for the proper functioning and long work life. This is also the case of medical equipment such as scalpels and ultrasonic scissors. Tuning means adjusting the frequency of resonance.
In the case of the sonotrodes, the tuning is accomplished by adjusting its dimensions to achieve the desired frequency employing machine tools (lathe, milling, and grinding) and the TRZ Horn Analyzer. Besides the frequency, the TRZ measures another fundamental parameter for the operation, which is the electrical impedance.
Even if the sonotrode is produced with high precision and reproducibility by a CNC machine, the frequency fine tuning is always a necessity. The elastic properties of an alloy differ from batch to batch or even in a single piece, especially for those subjected to tempering process. When you remove material from a sonotrode, the shortening of its length causes a rise in frequency, however it isn't possible to add material for its frequency decreases. Therefore, the the process of manufacturing a sonotrode consists of projecting the piece and machining it with a length slightly greater than the final length, and performs the wear at the piece together with the characterization by the TRZ Horn Analyzer until frequency rises and reaches the desired value.
When necessary, the ATCP provides customized consulting of TRZ Horn Analyzer application to facilitate the establishment of the tuning process of the sonotrodes in the customer´s facilities.
The prolonged use of transducers, boasters, and mostly acoustic sonotrodes is ultimately accompanied by wear and tear, that can compromise the performance of ultrasonic equipment and lead to damage. With the vibration, the reduction of the grip of the ceramics and the commitment of the joint surfaces becomes a possibility.
The TRZ Horn Analyzer allows periodic testing of acoustic sets in order to correct deviations before they have irreversible consequences.
The TRZ facilitates the reconditioning of ultrasonic transducers that have suffered from broken ceramics and the verification of grinding or lathe processes so as to correct the surface of sonotrodes.
The applications of the power ultrasound are vast and are continually expanding.
For the development and improvement of ultrasonic products, the availability of equipment such as the TRZ Horn Analyzer is essential.
The TRZ Horn Analyzer equipped with optional software enables the frequency chracterization and impedance of operation and visualization of the curve of the transducer (module of impedance versus frequency). From the visualization of this curve it is possible to identify and remove spurious resonances, for example.
For developments and / or specific improvements, the ATCP offers the services of characterization and consulting.
Technically, the TRZ is an impedance analyzer that can be used in electrical engineering teaching labs to demonstrate the concepts related to reactive systems, resonant circuits and power factor, since it also characterizes passive components in a manner similar to an LCR bridge.