Ultrasonic cutting knife, also known as ultrasonic cutting machine, is a kind of ultrasonic equipment specially used for cutting, and it is one of the important categories of ultrasonic applications. The principle of ultrasonic cutting is completely different from traditional cutting. Ultrasonic cutting is to use the energy of an ultrasonic transducer to heat and melt the material to be cut, so as to achieve the purpose of cutting the material. Therefore, ultrasonic cutting does not require a sharp edge, nor does it require a lot of pressure, and will not cause chipping or breakage of the material being cut. At the same time, because the cutting knife is doing ultrasonic vibration, the friction resistance is very small, and the material to be cut is not easy to stick to the blade. This is especially effective for cutting viscous and elastic materials, frozen materials, such as food, rubber, etc., or objects that are inconvenient to apply pressure.

The basic composition of an ultrasonic cutting knife is an ultrasonic transducer, an horn, a tool head (knife body), and a driving power supply. The ultrasonic drive power converts the mains electricity into high frequency and high voltage alternating current, which is output to the ultrasonic transducer. The ultrasonic transducer is actually equivalent to an energy conversion device, which can convert the input electrical energy into mechanical energy, that is, ultrasound. Its manifestation is that the transducer stretches back and forth in the longitudinal direction. The frequency of the telescopic movement is equal to the frequency of the high-frequency alternating current supplied by the driving power supply. The function of the horn is to fix the entire ultrasonic vibration system, and the other is to adjust the output amplitude of the transducer.

On the one hand, the tool head (cutter body) amplifies the amplitude and focuses the ultrasonic waves. On the other hand, it outputs ultrasonic waves, and uses the similar cutting edge of the cutting knife to concentrate the ultrasonic energy into the cutting part of the material to be cut. Under the action of huge ultrasonic energy, this part instantly softens and melts, and its strength is greatly reduced. At this time, as long as a small cutting force is applied, the purpose of cutting can be achieved.