| 1.Foreword Inorder to raise production quality , reduce wasted product , prolong the service life of machine tool, it is important to for machine tool to carrie out online monitoring of rolling bear .rolling bear fault diagnosis is also a long-term explore. vibrate signal has many special features such as: get easily; regularity strong; handle convenience; which make it become one of the best method of rolling bear fault diagnosis. 2.Rolling bearing trouble diagnose current situation of studying there are many articles concentrate on analysis on characteristic of signal of the fault and abstraction, mainly belong to two aspects. Resolve of the signal and the abstraction of signal. Resolve of the signal As has been widely accepted that: each kind of trouble modes has its corresponding characteristic frequency; Recently, the researchers have found some signals do not include the adding sin wave weight of any limited intensity typically, through non-linearly transformation, it can produce limited intensity sin wave. In addition, interval and friction between the spare parts, physical property , interval and restoring force , crackle , other defect , heavy out of shape , heavy displacement etc.. make the dynamics characteristic of the mechanical system have non-linear nature . abstraction of signal non-linear nature of system , and strong noise interfered at the working site, make it have certain degree of difficulty. Or even impossible sometimes to make the abstraction of the characteristic signal Therefore the abstraction of the signal becomes the trouble and e key to diagnoses. modern signal treatment technology brings the hope for solving this difficult problem day by day. Divide shape , Chaos , high-order statis, wavelet transformation , neural network ,etc. method favor by people. 3.Mechanism analysis of the trouble Chapter three analysed structure , common trouble , the reason to produce the trouble and characteristic frequency of each kind of trouble of the rolling bearing in detail . Since every trouble corresponding only characteristic frequency, we can detect whether the trouble exist through measure some trouble corresponding frequency, Monitor a certain frequency , build time series analysis can realize the prediction of the trouble . This is the theoretical foundation for instrument design. on this basis, have established the corresponding relation among the trouble and characteristic frequency. 4. The instrument designs and the analysis of the algorithm It is the core of this text, set up on the foundation of studying of trouble mechanism. Have the following function: 1)Input and calculate various kinds of characteristic trouble frequency with corresponding trouble according to users 2)DAQ 3)Draw the characteristic signal, judge according to the characteristic signal whether some trouble exists. 4)Selecting the signal of controlling, the array model of build-up time , carry on failure predication. This instrument is made up of hardware , software The hardware is used in DAQ , the data collecting card adopted on instrument design phase is PCI-6024E DAQ card produced by NI Company. For solve high-speed DAQ real-time control and data store problem, circulation to buffer technology has been adopted. Parameter of DAQ can adjusted. The software is formed by following part: 1) calculate the characteristic frequency of the trouble2)signal frequency is collected, 3)the amplitude is constructed 4)time series analysis is made ,5)parameter estimate , 6) to shine upon from complicated vibration signal to trouble mode based on neural network (just utilize neural network characteristic of itself, realize hints from vibration primitive signal to trouble). 5.conclution This system uses modern signal treatment technology and virtual instrument...
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