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1-4BearingSelection(2)Structureofproductsinuse/FunctionsrequiredofbearingsandAmongthebearingswhichareMinebeaMitsumi'smainproductsaremanyserieswithstandardizeddimensions.Selecttheoptimaldimensionsinordertofittheproducttobeusedintothespaceallowable.Aswell,selectbearingswithspecificationssuitedtothefunctionsrequiredandtheoperatingenvironment.Structureofproductsinuse/Functionsrequiredofbearings•StructureandfunctionofproductsinuseWorkoutbasedonthestructureandfunctionoftheproductinusethespaceusableforbearings,anddecideonthebearinginnerandouterdiametersandwidth.•LoadDecideonthebearingdimensionsbasedonthesizeoftheloadappliedanditspositionanddirection.Ifthesizeoftheloadappliedtothebearingistoolarge,theproductstructuremustbereconsidered(usingalargerbearing,reducingtheload,etc.).•Shaft/housingdimensionsandmaterialDecideontheinnerandouterdiameterandwidthofthebearing,andonitstolerance,basedontheshaftandhousingdimensionsandmaterial.Takeintoaccountchangesinthebearinginternalclearanceduetotemperaturechangecausedbydifferencesinthelinearexpansioncoefficientsoftheshaftandhousingmaterialandthebearingmaterial.•Rotationspeed,rotationprecision,rotatingringDecideonthebearingdimensionaltolerance,retainer,clearance,preload,lubricant,etc.basedontherotationspeed,rotationconditions(continuous/intermittent/returnrotation,innerringrotation/outerringrotation),androtationprecision.•TorqueTorque,whichincludesstartingtorqueandrotatingtorque,influencesthemotorcurrentvaluerequiredforbearingrotation.Inparticular,whenrequirementsincludelowpowerconsumption,etc.,thetypeandamountoflubricantrequireconsideration.•NoiseWhentherotationnoiseofthebearingmustbeminimized,thenoisepropertiesofthebearingandlubricantrequireconsideration.Aswell,attentionmustbepaidtoconditionsaroundthebearingsuchaspreload,unbalancedrotors,orresonanceduringbearinguse.28