Ultrasonic generators for cleaning
Introduction
An ultrasonic cleaner is a cleaning device that uses ultrasound (usually 15-400 kHz) and a suitable cleaning solution to clean delicate objects. Ultrasonics are not effective without the cleaning solution; These require an appropriate solution for each object and the dirt to be cleaned.
They are often used for cleaning in the manufacture of jewelry, lenses and other optical parts, coins, watches, surgical instruments, industrial parts such as automotive pipes, cleaning plastic injection molds, rubber injection, glass injection, electronic equipment and a great multitude of applications that have been discovered for this process. In everyday use, these devices can be found in use in most
from jewelry workshops, watch shops"), or in cell phone repair workshops (where it could be used for cleaning a phone that has
been exposed to sufficient moisture to prevent operation).
Design and principle of operation
In an ultrasonic cleaner, the object to be cleaned is placed in a stainless steel tank containing an ultrasonic-conducting liquid (an aqueous solution or organic solvent, depending on demand). In aqueous cleaners, the added chemical is a surfactant that breaks the surface tension of the base water. An ultrasonic generator (built-in transducers) built into the stainless steel tank, or immersed in the fluid, produces ultrasonic waves in the fluid by changing size in tune with an oscillating electrical signal at the ultrasonic frequency. This creates compression waves that "rupture" the liquid, leaving behind millions of microscopic "voids" or "partial vacuum bubbles" (cavitation). These bubbles collapse with great energy; at temperatures of 10,000 K and pressures of 50,000 pounds per square inch; but they are so small that they do nothing more than clean the surface and remove dirt and contaminants. The higher the frequency, the smaller the space between the cavitation nodes, allowing the cleaning of the most intricate details.
Transducers are generally made of piezoelectric material (for example, zirconate lead titanate) or barium titanate), and sometimes magnetostrictive (made of a material such as nickel or ferrite). Chemicals frequently used as cleaners in many industries are not necessary, or used in much lower concentrations, with ultrasonic agitation. Ultrasounds are used for industrial cleaning, in many medical and dental centers, and in process techniques. industrial.