Study On A New Method To The Torsional Vibration Testing Of The Elevator Traction Machine

The torsion and vibraton of elevator traction machine calls for short the torsional vibration of it. It has directly effect on the stationarity of the elevator in operation and the comfortable feeling of the passengers so much as the operational life span of the elevator. And it is an important qualificaton of the traction machine's performance. So every traction machine can be sold after the torsional vibration testing. At present, the torsional vibration of the traction machine is tested by the acceleration sensor which is installed on the traction wheel. When the acceleration sensor rotates with the traction wheel, the information is obtained. The sensor-lead which has 3-4m commonly has been wound round the traction wheel, and when it is over, the testing is over. As a result, the method can't be used to test continuously for long time and has not a good stability.To make up the deficiencies in the present method, the space-time transformation gear-grating testing method, a new method which can serially test the traction-wheel's dynamic characteristics, to the torsional vibration testing of the traction machine has been advanced in this paper. The specific operations are as follows: the traction-wheel has directly made into the gear-grating, and the two hall-sensors placed with the angle of 180°have tested the torsional vibration by non-contact, and the sensors have sent one signal when one tooth of the gear-grating has been rotated with the traction-wheel. The clock pulse, the time scaleplate, has been applied to implement the instantaneous calibration and real-time subdivision to the gear-grating which is the space scaleplate ( the invention patent,"A new method to the subdivision direction of the pulse signal by microprocessor"). So the instantaneous palstance of the traction-wheel has been tested and the continuous test for long time has been realized. And it has a high precision and a good stability.This thesis illuminates the fundamentals to the new method of the torsional vibration testing of the traction machine and advances a set of distributed testing analysis system, and this testing system is separated into up-machine and down-machine. The down-machine is the single chip integrate circuit. In this part, the signal from sensors has been preprocessed to get the better signal source. And two external interrupts (INT0 and INT1) and internal counter/timer (T0) in the chip microprocessor of AT89C51 are used to program the software, which can implement the judgement of signal sample points and the count of signal number. The high frequency inserted pulse is used to time the signal. And then all data which should be tested is collected. However, the up-machine is the PC software. In this part, two threads'implement system have been adopted to get the collected data and process the data and display the test results. This software, designed the friendly interaction-interface between people and computer, has taken the Visual C++ which is the popular and high-level langeage for the programming flatform. So it is very simple for users. The USB interface has been adopted to implement the intercommunication between the up-machine and the down-machine, and at the same time, the data has been transmited by the format of the data-packet.In experiment process, the PCB board of the down-machine had been made in the test system. Two roads designed simulation-signal, P1 and P2, have been used in the test system which implements the simulated experiment of the new method of the torsional vibration testing. The experiment results and analyses have been gived. At last, as for the traction machine which can load 1 ton, we have designed a set of sample piece to experiment and performed the load-on experiment. And the correctness and feasibility of the space-time transformation gear-grating testing method has been proved.