The technology of ultrasonic cleaner possesses a history of more than 30 years, it has already been applied in Japan 25 years ago, but there is a misunderstanding regarding this technology, making people suspect the effect of ultrasonic cleaners. The traditional ultrasonic cleaner theory held that the bubbles play a role of cleaning. After repeated experiments, it was discovered by Caiye Jiaying that the bubble is the mere gas explosion resulted by the strong coarse intensive wave of ultrasonic actually, which can impede or even eliminating the cleaning capability of ultrasonic cleaners, in fact, it is the vacuum cavitation that plays the role of cleaning. Such finding realized the revolutionary breakthrough in the field of ultrasonic cleaner.
In the year of 1987, the basic theory regarding ultrasonic cleaner was proposed by Caiye Jiaying, for distinguishing it from the traditional theory, he named the research finding as “Caiye theory”, on this basis, the ultrasonic cleaner technology was defined as the new ultrasonic cleaner technology. The ultrasonic cleaner device developed according to this theory possesses better cleaning effect than other products of the same kind, which can control the occurrence location, occurrence density, occurrence efficiency as well as the impact force of cavitation phenomena successfully. The welding burrs cannot be cleaned and removed well through 25 minutes of cleaning by other manufactures of the same industry, which can be eliminated in only six seconds by applying the cleaning device of Pleiades; For the dense welding part which cannot be removed by the device of other manufacturers in the same industry in two hours, it can be eliminated by Pleiades in two minutes, preventing the processed materials from damage.
Speaking of the birth of “Pleiades” as well as the research process for ultrasonic cleaners, Caiye Jiaying becomes very excited. In the year of 1970, Caiye Jiaying graduated from the major of electric engineering for National Fukushima Industrial Junior College in Japan, he worked in the Janome Sewing Machine Industrial Technology Research Institute. In the year of 1975, he entered an industrial cleaning company, at that moment, the ultrasonic cleaners were developed, but the toxic and harmful chemical solvent such as Trichloroethylene and Freon were utilized in large amounts as the cleaning medium, which has polluted the environment severely. At that time, the industry in Japan was developing rapidly, a large amount of industrial waste was discharged into rivers, many people got sick for drinking such water, especially some disabled people died early because of working in toxic and harmful environment. After witnessing all of this, Caiye Jiaying decided to bring benefit to mankind with environmental technology driven by his strong sense of social responsibility, he said: “the world nurtured me, I have the duty to make contributions to the world!” Therefore, he stepped on the road for making researches on environmental ultrasonic cleaners.
He discovered the secret of ultrasonic cleaners by chance. At that moment, due to insufficient capitals, he can only carry out simple experiments with insufficient experimental equipment. Because the closed trough for ultrasonic cleaners were made of stainless steel mostly, the condition of ultrasonic in medium cannot be observed from the side view, for saving money, Caiye Jiaying bought a transparent plastic fish tank to replace it, in this way, the change in cleaning trough can be observed easily. According to his findings, the many bubbles produced by the ultrasonic generator placed at the bottom of fish tank rise constantly, a big bubble can split into two small bubbles, at last, it will explode. The principle of traditional ultrasonic cleaner lies in producing bubbles through the diffusing ultrasonic in liquid medium, then realizing the effect for cleaning the subject surface by means of the force produced by bubble explosion. However, due to the existence of air in bubbles, the force produced by bubbles is limited, therefore, the cleaning effect is not desired. After repeated experiments, Caiye Jiaying has made constant improvements, at last, the new ultrasonic cleaner device was developed, making the bubbles become vacuum cavitation, which has corrected the misunderstanding of people towards ultrasonic cleaner technology for a long time. He has also tried to utilize water for replacing the previously frequently used toxic and harmful medium of Freon for ultrasonic cleaners, taking a step forward towards the environmental goal, in the year of 1993, such invention has obtained the “United States Environmental Protection Agency (EPA) Protection of the Ozone Layer Environmental Protection Award”. The digital meter he invented can measure the sound pressure and cavitation impact force of ultrasonic at any time, thus adjusting the cleaning device to the optimal status.
In the recent 10 years, the ultrasonic cleaning device was developing in two aspects. For one thing, the multi-cylinder type or transmission chain type or elevation (over-and-under) type ultrasonic cleaning production lines of various types came out in the market one after another; For another, the low-frequency ultrasonic cleaner was transforming into the high-frequency ultrasonic cleaner. In American, Japanese, European, as well as Asia-Pacific markets, the total amount of multi-cylinder type ultrasonic cleaning device was increasing obviously, which accounted for 50 percent of the total, whereas, the multi-station semi-automatic and full-automatic transmission chain type or elevation (over-and-under) type ultrasonic cleaning line device have reached more than 40 percent of the total amount.
The application of ultrasonic cleaning technology in China has achieved better effect. Firstly, the high cleaning degree was required for cleaning the mechanical components before and after electroplating or coating as well as the cleaning for disassembled components, such as oil pump nozzle couples, bearing, brake, fuel strainer and valves. Secondly, the cleaning for printed circuit boards, silicon wafers, wafers, component shells, seats, signal control relays for railway systems, components, connectors, picture tubes and electric vacuum devices. Thirdly, the cleaning for glasses, microscopes, telescopes, optical sights, other optical systems and sampling glasses. Fourthly, the cleaning for various bottles and cans utilized in medical equipment, food, pharmaceutical, biochemical and other tests. Fifthly, the cleaning for spinning jet, precision molds, precision rubber parts, jewelry crafts and so on.
At present, there are nearly 40 ultrasonic cleaning device manufacturing enterprises of various kinds in China, but they are mainly located in southeast coastal regions. According to the statistical information, the manufacturers of coastal regions accounted for 85 percent of national total number, it can be observed that there is leading and extensive application of ultrasonic cleaning technology in developed regions, which has enjoyed great popularity, in the meantime, this has proved that there is a promising prospect for the application and popularization of ultrasonic cleaning technology in mid-western regions. As far as the product quality is concerned, comparing the contemporary products with those of 1970s to 1980s, the technology has been improved significantly. In recent years, due to the technical transformation performed on the traditional cleaning technology of automobile brake production line and refrigerator compressor production line, the ultrasonic cleaning technology shall be applied. As for the ultrasonic cleaning of foreign automobile carrier frame and automobile coating spraying, it should be equipped with specialized cleanout fluid, accomplishing the one-time cleaning treatment of rust removal, oxidation film removal and phosphating, there are new applications and development for paint spraying after drying.
The American Advanced Sonic Proctssing Svstems Company has launched a series of devices for large amount cleaning coal or precious metal minerals, for example, to clean the soil and colloid substance on the surface of metal particle mineral, giving full play to the function of chemical agent;Cleaning baring powder coal, removing dust or eliminating sulfur, the processing ratio can reach tens of tons for each hour.
According to the application report of American Dvpont company in New Jersey pharmaceutical factory: ultrasonic cleaning can remove the dirt on the surface of chemical treatment bucket or reaction can, which is more energy saving compared with ordinary methods, with low cost and reduced environmental pollution, the cleaning process is very simple, only to fill the container with water, heating it to 65℃, and adding 2 percent of surfactant, conducting treatment for two to four hours, then it can be cleaned up.
Some European manufacturers once cleaned cans of 9.1 cubic meters, previously, they are heated to the boiling with pointmethyl alcohol and treated for four to eight hours, the requirement can be realized after five cleaning in total, and the requirement can be reached with only one treatment for ultrasonic cleaning, which can save the solvent, increase efficiency and reduce environmental pollution
With the increasingly extensive application range of ultrasonic cleaning device, the various kinds of new and improved ultrasonic cleaning devices are replacing the old ones.
The megahertz ultrasonic cleaning technology means to apply the ultrasonic with frequency from 700KHz to 2MHz to perform cleaning. The cleaning system is generally composed of piezoelectric transducer display, cleaning container and clean-out fluid, high-frequency electric power generator and control circuit, for some special cleaning objects, sometimes it is equipped with the filtering circulation system of hot-air drying, specialized cleaning rack (basket)and clean-out fluid.
As for the major characteristics of megahertz ultrasonic cleaning technology, firstly, preventing the surface damage of high finish object; Secondly, removing the particles with submicron size attached on the surface; Thirdly, soaking in fluid, the surface facing to transducer can be cleaned, so it is necessary to conduct double-surface cleaning.
