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      As we all know, an ultrasonic cleaning machine consists of two parts: one is an ultrasonic generator, and the other is an ultrasonic cleaning tank with a transducer as the core.

      Ultrasonic generator is simply a high-power source that matches the frequency of the transducer.

      In general, the technical status of ultrasonic generators and ultrasonic cleaning cylinders with transducers as the core is far from keeping up with the development of the times and the needs of many fields of my country's economy. The production status of ultrasonic cleaning machines is characterized by outdated and backward technology, unsatisfactory cleaning efficiency and high failure rate. This has become a bottleneck restricting its further expansion of the scope of application. At present, the market is not guided by improving technology, improving design, simplifying process structure, reducing costs, and improving its cost-effectiveness, but often competes with each other at low prices, which has brought a negative impact to the development of the entire industry and ultrasonic cleaning business. , should cause our attention.

      As far as we know, in East China, the standard of ultrasonic generator is nothing more than the following:

      1. The first generation of products are electronic tube type. With the advancement of technology, they are already eliminated products (but there are still manufacturers in production).

      2. Imitation of the ultrasonic generator of Branson Corporation in the United States, the single board power is 300W, the frequency is fixed at 25KHz (self-excited half-bridge output circuit), and it is equipped with a large power transformer, which is the market share. A simple model with the highest rate. However, it is difficult to adjust the circuit at the optimum frequency resonance point of the ultrasonic transducer, and the output power cannot achieve the desired effect, and the quality is self-evident. However, considering that the circuit of the generator is relatively simple, the stability is acceptable, the whole machine is well debugged, and the failure rate is still very low, and there are many enterprises producing this type of small and medium-sized ultrasonic cleaning machine. How to improve and improve the circuit? We provide the following design scheme for reference: remove the power transformer, reduce the magnetic leakage of the output matching transformer, and achieve the purpose of reducing and reducing the weight and volume of the whole machine, reducing the cost and improving the efficiency. To remove the power transformer, we must first consider solving two problems, one is the insulation problem between the power input and the high-frequency power output; The safe operation of the machine (the power supply voltage of the original machine is about between DC150V-180V). The circuit introduced in Figure 1 can solve the problem that the supply voltage meets the design requirements of the original machine. Note: Pay attention to safety during debugging to prevent electric shock.

      The output transformer of the original machine uses a single magnetic core, which has a large magnetic leakage. Once it is close to the iron shell, an eddy current will form and generate high heat. It is recommended to use an IE magnetic core. The single group is changed to primary and secondary double windings, so that the isolation and insulation problems between the power input and the high-frequency power output can be solved. Due to many uncertain factors, it is difficult for us to give a definite data for the relevant technical parameters of the output transformer, such as the number of turns, the turns ratio of the primary and secondary, and the inductance.

      3. MC model and its improved model: This is also an old product, and the circuit design is cumbersome. Due to historical reasons, it is a product that is not designed in place. Gate circuits are used a lot, SCR voltage regulation, complicated process, high failure rate, has been neglected by users, the former well-known state-owned factory that produced this model, we think that only reluctantly get rid of the old and backward models, develop or Only by choosing new models can we revive the former glory and stand on the market today.

      The improved model simplifies the circuit and adds "frequency hopping" synchronization technology. The so-called "frequency hopping" is actually a multivibrator added to the main oscillation frequency of PWM , and its frequency matches the main frequency, and the output pulse of the oscillator then modulates the main vibration pole. Although the constant power output is achieved, due to the limitation of the current capacity of the power element MOSFET, the full power output is not achieved, the output power is not satisfactory, the cleaning efficiency is not significantly improved, and the application industry is not wide, especially each jump There is always a periodic sound in the cleaning tank, there is no slow start function, and there is a "power adjustment" knob. Once the operation is wrong, it will fail, and it cannot be linked with other equipment.