How can the ultrasonic handpiece in a CNC machine dynamically adjust the frequency and amplitude of ultrasonic vibration to achieve optimal machining results?
Publish Time: 2026-02-28
In modern precision manufacturing, ultrasonic-assisted machining technology is becoming a powerful tool for tackling hard and brittle materials and difficult-to-machine alloys. The ultrasonic handpiece in a CNC machine, as the core terminal for energy transfer, directly determines the success or failure of the machining process. Faced with complex variables such as changes in material removal rate, tool wear, and temperature fluctuations during machining, the ultrasonic handpiece must have the ability to dynamically adjust its frequency and amplitude to always lock onto the optimal resonance state, achieving efficient and low-loss machining.1. Frequency Tracking: "Automatic Navigation" to Lock the Resonance PointThe core principle of ultrasonic machining is to use piezoelectric ceramic transducers to convert high-frequency electrical energy into mechanical vibration. However, the transducer system has an extremely narrow "resonance frequency bandwidth." Energy conversion efficiency is highest only when the driving frequency is perfectly matched with the system's natural frequency. During machining, as the tool's depth of penetration into the material increases, the cutting force changes, and the temperature rises, the mass, stiffness, and damping characteristics of the entire vibration system undergo slight changes, causing the natural frequency to "drift." If the driving frequency remains unchanged, the system will quickly detune, the amplitude will drop sharply, and it may even lead to transducer overheating and damage. The CNC ultrasound handpiece incorporates a high-precision phase-locked loop or automatic frequency tracking algorithm. The control system monitors the transducer's impedance phase angle or admittance circle trajectory in real time.2. Amplitude Control: A "Flexible Hand" Adapting to Material PropertiesIf frequency tracking ensures the "input efficiency" of energy, then dynamic amplitude adjustment determines the "output effect." Different materials and different processing stages have drastically different requirements for vibration amplitude. Excessive amplitude may cause chipping of hard and brittle materials or tool breakage, while insufficient amplitude cannot produce an effective impact breaking effect, resulting in low processing efficiency. The ultrasound handpiece achieves precise amplitude control through a closed-loop feedback system. The system uses a built-in laser displacement sensor or an estimation algorithm based on a current/voltage model to calculate the actual vibration amplitude of the tool tip in real time. The operator can preset the target amplitude value on the CNC interface. When the system detects that the actual amplitude decreases due to increased load, it automatically increases the drive power to compensate for the loss; conversely, it automatically reduces the power under no-load or light-load conditions to prevent excessive amplitude.3. Intelligent Collaboration: Adaptive Optimization of Process ParametersThe highest level of dynamic adjustment is not isolated frequency or amplitude control, but rather the intelligent collaboration and process adaptation of both. The new generation of intelligent ultrasonic handpieces can deeply interconnect with the CNC system, reading parameters such as spindle speed, feed rate, and depth of cut in real time. Based on the built-in process database and AI algorithms, the handpiece can predict the changing trends of the machining state.In summary, the CNC equipment ultrasonic handpiece successfully solves the pain points in the machining of superhard materials by locking the resonance peak through real-time frequency tracking, adapting to varying loads through closed-loop amplitude control, and achieving adaptive optimization of process parameters through intelligent collaboration.
