Research On The Fuel Economy And System Reliability Of Metal V-belt CVT

The Continuously Variable Transmis sion(CVT)is suppo sed to be theideal transmis sion,because it can decrease the driver's w-ork,improve thedriveability,offer the brilliant vehicle Performance and emis sion Now it ismore and more Popular with the Chine se customer and motor manufacturerHow-ever,in the engineering application,the transmis sion lo s s have to bedecreased and the reliab ility of CVT are nece s sary to be improved Thetransmis sion lo s s will affect the fuel economy and the system reliability,including the mechanical system reliability and electronic system,reliability,is a keY point to the transmis sion serVice life Therefore,the setwo factors are very important to the CVT engineering applicationWith the reliabilitY of CVT,the finite element method is apPlied onthe deformation and stre s s analys is Based on a 3-D model of secondaryPulleY of Continuously Variable Transmis sion,the finite element method isused to analyze the pulleY deformation with certain axial force and ratioAfler that,the mathematic model about maximum PulieY deformation valueand Po sition are develoPed with the re sult of finite element methodComparing with the experimental data,the finite element method isvalidated The resuIt show that the ratio is the mo st important factor toaffect the po sition of maximum deformation and the axial force and ratioaffect the value of deformation together The mathematic model andanalyzing method is useful in the PulleY de sign and CVT efficiencY re searchAfler the stre s s and deformation analys is,the te st rig about mechanicalreliability is develoP ed Based on the CVT data of input torque,input sPeedand ratio,c01lected in the Proving ground,the~-avelet multi re solution isused to filter out the high frequencY s ignals,which had little effect on thefatigue damage of CVT Then the CVT rat io and input speed were send tothe CVT cont rolier and motor controlier re spectively and then the obj ectdata is rePeated the te st rig The TIC(The il inequalitY coeffic ient)valueshow that the system is a effective te st Platform fo r the reliability Based onthe theorie s of adaptive AR spectrum and neural network,a fault diagno s ismethod for bearings in CVT is P re sented The method use s adaptivefiltering technique to filter the Vibration signals of bearings,sets up an AR model to extract the features 0f faUItY bearings．and utilizes neural networkto clas Sify the faults The te st re sults Show that the apP roach canefiectively identify the faUIt patterns of transmis Sion bearings About thereliability 0fCVT C0ntroller,the Failure Mode and Effect Arialysis(FEMA)and FauIt Tree Aanalysis(FTA)method are used to do the Potential failuremode and efiects analys is AcC0rding to the Porential failure mode．thediagnose code and tolerance control strategy are deVeloPed Theexperimental data show that the tolerance Control strategy is effective toProtect the transmission and the vehicle With the loss of CVT,a simulationmodel with MATLAB M-C0de is deVeloPed to evaluate the affection of Pumploss and beIt loss to the vehicle fue 1 consumption,based on the loss data ofPump and belt Comparing with the te st rig data．the Simulation re suIt isconfirmed to be accurate For improVing the the efficiencY of CVT．the slipcontrol strategy is applied on decreasing the Clamping force and increasethe friction coeffic ient The Simulation show that it is an efiectiVe methodto improVe the CVT'S efficiencY under the Pre sent teChnology and CVT lossAfter that．a test rig for the efficiency test is deVeloped hased on thePrinciple of hardware in the looP Simulation AcCOrding to the vehicleSliding data．a vehicle load model is USed in the te st rig and repeated bY theA/C motor And the driver model is simulated by the electronic throttleC0titr01With CVT fuel economy and reliabilitY．S0me innovation work can beseen in the reseach:(1)AcC0rding to the FEM re sults,a law-about pulleydeformation．in different axial force and ratio．is developed for reducing thealigement Setting and improving the mechartical system reliability(2)Aw-avelet is used in the ground test signals processing．for developing theCVT reliability test system.Meanw-hile,a fauIt diagnosis method,based 0nthe adaptive AR spectrum．with bearings in CVT．is presented in this paperThe test system is helpful in analyzing the CVT C0mponentsreliability(3)Based 0n the Principle 0f hardware in the loop Simulation,aninnoViation fuel eConomy te st System is develoPed for improVing the CVTdeVe loping effic iencY (4)the FEMA and FTA method are used to d0 thepotential failure mode and efiects analys is According to the potential failure mode,the diagnose code and tolerance control strategy are developed for guarantee the passanger safe...