The Design of Force Measuring Tool Holder System Based on Wireless Transmission

Cutting force can be used in monitoring machine processes and for guiding production. Therefore, the measurement of cutting forces has significant meaning in research. In this paper, an innovative force measuring tool holder system was presented, which integrated strain sensors and wireless transmission devices as well as created real-time measure axial force and torque in milling and drilling processes. In order to improve the sensitivity of the detection system, an annular groove was cut on the standard commercial tool holder. The Sensors of axial force and torque were arranged in the middle of the annular groove to perceive the minimal deformation in a corresponding direction. The structure of the tool holder was designed by optimization in which the required stiffness is used as the constraint and the detection accuracy is the highest as a target. All of the sensors and other electronic components, such as the data acquisition and the transmitter module and the power module, were integrated with the tool holder as a whole system. The equipment could be clamped on the spindle hole of the milling or drilling machine. A static and dynamic calibration test platform was built, and the static calibration test platform determined the testing performance with a wide range. Cutting tests were performed on a floor type boring-milling machine. The results were consistent and had a high waveform degree of coincidence on the axial force and torque trend compared with the Kistler dynamometer. The results also accurately reflected the axial force and torque changes in dynamic milling and drilling.