The Design Of Lifting Force Detection Device Of Electromagnetic Yoke Magnetic Particle

In order to prevent the phenomenon of measurement results are not allowed or missedoccurrence when testing is performed on the work piece, magnetic particle detector must becorrect calibration on a regular basis. Yoke lifting force index is an important indicator when theyoke magnetic particle detector has a calibration. Only determine the measurement range of thelifting force yoke, we can guarantee the quality of the magnetic particle testing the better. Thissubject takes a research on the yoke lift force detection device for the measurement of the yokelifting force.At first, the article analyzes the detection principles of magnetic inspection technologies anddevelopment status at domestic and international. Then we analyzed the yoke magnetic particledetector calibration procedure of our country. From the calibration procedure we can see that thetraditional method of weighing iron to measure the yoke lifting force is not reliable, and can’tmeasured specific values of the lifting force. After analysis and research the development of yokelifting force at domestic and international, we summed the relationship of the yoke lifting forceand the magnetic attraction. By calculation formula of the magnetic attraction, we can deduce thecalculation formula of the lifting force of the magnetic yoke. Based on the relationship of themagnetic attraction, yoke lifting force and the plus pull as the theoretical, we proposed toindirectly measure the magnetic attraction by measuring the plus pull, so we can reach the purposeof measure the yoke lifting force.Then we have a test on measurement program by using this two methods of dynamicsampling and static sampling. The dynamic sampling means sampling the tension sensor outputvoltage when the motor drag a steel sheet. The static sampling means the measurement processdiscretization by controlling the motor rotation, so that the sampling of tension sensor outputvoltage and the rotation of the motor have been separated. And we use the high-speed dataacquisition card to sampling data. After that, we draw a graph of the measured tension changesand take a comparison and analysis. At last, we choose a more stable static sampling method as themeasurement methods of lifting force. In the process of measuring the lifting force, we use the method of stoke discretization and time discretization to sampling in order to close to the truevalue of the lifting force. In second, we use the Exponential acceleration and deceleration controlmethod to prevent the stepper motor has the phenomenon of overshoot or out-of-step. Finally weuse median average filtering method to filter the data obtained, in order to prevent the noise andmechanical vibration. So, we can get a more accurate lifting force data. After have an analysis onthe data of the experimental results, we can see that we proposed the lifting force measurementsolution is feasible and more reliable than traditional method.By taken a research on Yoke lifting force measurement method, we have designed a set ofyoke lifting force detection device for yoke magnetic particle detector. The full-text introduces therealization method and the design of each module of the apparatus. At last, according to the actualmeasurement data, we analyze its performance; make a contribution to the calibration of themagnetic particle detector.