Different from traditional processing technology, the basic principle of ultrasonic cutting technology is to use an electronic ultrasonic generator to generate ultrasonic waves of a certain range of frequencies, and then the original amplitude and energy are small through an ultrasonic-mechanical converter placed in the ultrasonic cutting head. The ultrasonic vibration is converted into mechanical vibration of the same frequency, and then amplified by resonance to obtain a large enough amplitude and energy (power) to meet the requirements of cutting the workpiece, and the energy is transmitted to the tool at the top of the ultrasonic cutting head for prepreg. Cutting process with belt. According to the actual requirements of the tape laying process and the ultrasonic cutting of prepreg, combined with the research results of ultrasonic application at home and abroad, the ultrasonic cutting system designed and developed by ourselves mainly includes three parts: ultrasonic cutting generator, ultrasonic cutting vibration system and ultrasonic cutting mechanism. The ultrasonic amplitude is provided and controlled by the ultrasonic generator and the ultrasonic cutter; the mechanical platform mainly controls the lateral movement of the ultrasonic cutter, the rotation about itself, and the cutting pressure provided by the pneumatic control system.
Ultrasonic cutting generator
The ultrasonic cutting generator is an ultrasonic power source, and its function is to convert 220V or 380V AC into an ultrasonic frequency electrical oscillation signal. In general, the ultrasonic device works well when used alone, mainly because the overall impedance is fixed during design and the power is easy to match. In actual use, the device is installed on the whole device, and is affected by many factors such as load, interference and temperature, which often causes drift of system parameters such as resonant frequency and equivalent impedance, so that the frequency of the ultrasonic generator and the transducer are The frequency mismatch causes a large loss of output power and a decrease in the amplitude of the transducer, which does not guarantee the quality and efficiency of the cutting. The ultrasonic generator in the system has an automatic frequency tracking function, and the frequency is automatically tracked through software and hardware, so that the impedance and the frequency can be matched at any time according to the field change, so that the ultrasonic vibration system is in a working state and conversion efficiency.
Ultrasonic cutting vibration system
The ultrasonic cutting vibration system is mainly composed of an ultrasonic transducer, an ultrasonic horn, and a cutting blade. Among them, the function of the ultrasonic transducer is to convert the electrical signal into an acoustic signal; the horn is an important component of the ultrasonic processing equipment. It has two main functions: (1) the energy gathering action is to amplify the mechanical vibration displacement or velocity amplitude, or concentrate the energy on a smaller radiation surface to collect energy; (2) effectively transfer the sound energy to the load as a mechanical The impedance transformer performs impedance matching between the transducer and the acoustic load to allow ultrasonic energy to be transmitted from the transducer to the load more efficiently. The system uses a combination of ultrasonic horn and cutting blade. In order to obtain a large amplitude magnification (Am), a stepped horn is used; in order to improve or reduce the stress concentration at the sudden change of the section, a circle is used at the sudden change of the section. Arc transition mode.
Ultrasonic cutting mechanism
The ultrasonic cutting mechanism includes a driving system, a pneumatic control option and a mechanical platform, and mainly performs several functions such as application of cutting pressure, precise positioning of cutting depth, control of cutting speed, and fixing of cutting workpiece.