Key Technology And Realization Of The Instrument For Signal Collection

Big-size bearings are important units of large-size hoist-transportation equipments. They have tight structure and they work equably. Also, little dynamic load is one of their advantages. So they are used in many circumstances. But people have only a little knowledge of them. Also, poor design and bad using of them are also acute problems. These problems affect the normal production of many firms.Vibration analysis is the main method of the big-size bearings trouble diagnosis. The signal of vibration can reflect run state and texture damages of the machinery. Because the high frequency of bearings and long cyclic time , the ordinary instrument for the signal collection can not save the large number of datum. Development of a type of portable .conveniently on-the-spot collection , high sampling frequency and large memory capacity instruments is very important.The main section of the large-size bearing trouble diagnosis instrument is a microprocessor. It can collect, save, analyse data preliminarily and transfer datum to computer on the work sport. It's memory capacity is 1.5M. It can collect the signal of two big-size bearings including six testing spot at the same time in 2560Hz sampling frequency . It can protect the data without electricity. In order to process the collecting signal further, the large-size bearing trouble diagnosis instrument can calculate effective value and peak value of every area.The following paper is about a type of instrument for the signal collection that can be used to monitor big-size bearing . The key technology about it is also introduced .During the analogue section, principal line is analogue signal Pspice simulation. In this section ,the main content is about the transducer and the low- pass filter. The simulation program of wave filter circuit and the stability of wave filter and analogue signal PSPICE analysis are integrated in chief. Theseare constituted as a circulatory feedback mode, so that it speeds the process of establishing electric circuit parameters.During the design of the microprocessor section, principal line is microprocessor interface. And some important problems of the system design was researched mainly. When hypothetical conditions of sampling time and data precision are sufficed, A/D574 was choosed . Not only the A/D574 has low cost and convenient interfaces ,but also because the A/D apply more converters and the information of it gathering is handy. The extension of the microprocessor memory , the keyboard and display adopt typical circuits. Because this system have to expend a lot of memory, I/O are used masterly in order to satisfy the design demand.From the practical effect , this production has low net cost, but it has good performance. The system of this instrument is flexile and it can be expanded. It can not only be used as big-size bearings trouble diagnosis instrument , but also it can be used as large data saving capacity and high frequency data collection instrument. Now, this large-size bearing trouble diagnosis instrument is used widely.