During the machining process, the oil film formed by the lubrication system serves as the core barrier ensuring stable equipment operation. Its thickness directly impacts machining accuracy, part quality, and equipment lifespan. An excessively thin oil film can lead to direct metal contact, causing wear and adhesion issues, while excessive thickness increases energy consumption and reduces transmission efficiency. Therefore, precise monitoring of oil film thickness and real-time regulation have become critical aspects of machine tool maintenance under the context of smart manufacturing. The innovative application of eddy current sensor technology provides reliable technical support for this requirement.
Eddy current sensors are widely used in machine tool oil film thickness monitoring due to their high sensitivity, excellent stability, and non-contact measurement advantages. The working principle is based on electromagnetic induction: when a high-frequency alternating current is applied to the sensor coil, an alternating magnetic field is generated. When the sensor approaches a moving metal component, the metal surface induces eddy currents. The magnetic field produced by these eddy currents interacts with the sensor coil's magnetic field, causing a change in coil impedance. The oil film thickness directly affects the equivalent distance between the sensor coil and the metal component, thereby altering the impedance parameters. A dedicated signal processing module converts the impedance changes into readable oil film thickness data. These sensors feature fast response times, enabling real-time capture of dynamic oil film changes under high-speed operating conditions. They are suitable for monitoring critical moving components such as spindles and guideways, and their compact structure facilitates easy integration into existing machine tool systems without affecting normal equipment operation.
The application of eddy current sensors in monitoring oil film thickness in machine tools not only enhances the reliability of equipment operation and reduces maintenance costs but also drives the development of precision and intelligent machining. In the future, as the miniaturization, integration, and intelligence of eddy current sensors continue to advance, they will deeply integrate with technologies such as big data and artificial intelligence, enabling predictive maintenance of oil film conditions and injecting stronger momentum into the refinement of smart manufacturing systems.