Study On The Measurement Method Of Dynamic Stress And Strain For High-speed Rotating Machinery

In recent years, the CNC technology has been developedt rapiddly.High-speedmachining centers and milling machining center is assembled from manyparts.Among them, high-speed turning motor spindle and high-speed turning tooldeveloped rapidly.Domestic and international mainstream high-end CNC lathe spindlespeed can reach6000~8000rpm, while the turning electric spindle highest speed upto20000rpm.However, the power chuck is still a weak point.The main limiting factor for thespeed of the power chuck is that the centrifugal force causes the chuck strength failureand clamping force insufficient at high speed. The rapid destruction tests of the powerchuck showed that the maximum speed of the chuck strength failure is much higherthan the clamping force insufficient Therefore, the clamping force is the mostimportant reason, which restricts the power chuck speed increase and cause insecurity.Therefore, there is an urgent need for a monitoring system to be able to long-linemonitoring chuck clamping force changes with the speed.The system can ensure thatpeople have a real-time understanding of chuck clamping force performance in thedifferent speed.First, the article determine the shape of the sensor; using ANSYS software,Create the clamping force sensor`s model to analyze the characteristics of the strain,look for the sensitive points of the sensor`s strain, Determine the placement method ofstrain gage and its bridge; Completed its size optimization design, to improve thesensitivity of the sensor; Get the reasonable ratio between the inner diameter and outerdiameter; Then analog high-speed rotation to understand the influence of centrifugalforce on the sensor itself.Secondly, the article studied wireless transmitter circuit for the sensor. Takinginto account the measurement device is installed in a high-speed rotation of the chuck,the signal collected by the sensor must be passed out by wireless. Therefore, we needto study the reliability of the power supply mode, which is suitable for high-speedrotation state. The same time, the article studied how to achieve a good signaltransmitter in the case of efficient and low consumption.The study speedmeasurement circuit.After that, the study of the digital signal wireless receiver, MCU and PC serialcommunication. And use C++to write system software, to achieve a system of datacollection, temperature compensation, scale conversion and recording, real-timedisplay the curve of clamping force increases with the chuck speed changes.Finally, did the composition commissioning for sensor, hardware circuitry andsoftware, calibration, and experimental verification. Real complete the tasks of powerchuck online monitoring, And compared the theoretical analysis and experimentalresults.Evaluation of research results.