ֻ33ज ֻ2௹吉林大学学报(工学版) ୍4ᄅJournalofJilinUniversity(EngineeringandTechnologyEdition) ໓ᅣщݼ:1671-5497(2003)02-0038-03CNCӚԵົྩྟඣ֥ࡎ陈殿生1,2,肖英奎2,贾亚洲1(1 吉林大学机械科学与工程学院,吉林长春 130025;2 长春工业大学机电工程学院,吉林长春 130012)ᅋ ေ:通过对现场采集的226条数控车床维修时间数据的分析,建立了其维修时间的分布模型,CNC车床维修时间服从对数正态分布,从而得出了其维修性特征函数(维修度函数M(t)a概率密度函数m(t)a维修率函数 (t))b在此基础上对CNC车床的维修性水平进行了评价bܱՍ:CNC车床;维修性;对数正态分布ᇏٳোݼ:TG659 1 ໓ངѓ്:AEvaluationofmaintainabilitylevelofCNClathesCHEND1,2ian sheng,XIAO21Ying kui,JIAYA zhou(,JilinUniversity,Changchun130025,China;,ChangchunUniversityofTechnology,Changchun130012,China)Abstract:Afteranalyzing226datasofrepairingtimecollectedinfield,,includingmaintainabilitydegreeM(t),probabilitydensitym(t)andmaintainabilityrate (t), ,:CNClathes;maintainability;lognormaldistributionCNCӚԵ൞ऎႵۚ॓ݣਈ֥ࠏ၂ุ߄Ӂbෛሢඔ॥ۿି֥҂؎ิ,ۚ༢ರگᄖ,၂֊ԛགྷܣᅰ,ࣼ߶ᄯӮऍնാbऌ࠹[1],ႮႿCNCӚԵؿളܣᅰط֤҂֞ࠣൈົྩᄯӮ֥ളӁ๔ࠏാૄ୍ၛ తຣჭ ࠹bၹՎCNCӚԵົྩྟ࣮ࣼӮູ၂۱ታրࢳथ֥ज़ีbູਔധೆ࣮CNCӚԵ֥ົྩ,ྟቔᆀฐษਔົྩൈࡗ֥ٳ҃ܿੰࠣఃཌྷႋ֥ඔ࿐ଆ,֤ԛົྩྟหᆘਈ,ࡎԛCNCӚԵ֥ົྩྟඣb1 ྩگൈࡗٳ҃ଆ֥ࡌഡгᆀགྷӆ۵ሶҐࠢਔଖCNCӚԵᇅᄯӌളӁ֥14ඔ॥ӚԵჿ2୍ᇏ֥܋226่ܣᅰົྩൈࡗඔऌ,ѩؓఃࣉྛਔೱ࿊ބᆜbᄝ൫ဒඔऌٳ҃োໃᆩൈ,൮༵ࡌഡӁ֥ٳ҃োbඔٳ҃൞Ⴈটᆜ൫ဒඔऌѩᅳԛఃܿੰྟ֥၂ᇕӈႨٚمb๙ݖྙ֥ྙሑॖၛԚ҄؎ھඔऌ(ဢЧ)൬۠ರ௹:2002 12 18bࠎࣁཛଢ:ݓࡅ ࣴ ᇗׄ॓۾ܱሧᇹཛଢ(97 776 03 01/02)bቔᆀࡥࢺ:ӧള(1969-),ଳ,ࠝਟړჅದ,ڬ࢝൱,Ѱൖ࣮ളb
第2期陈殿生等:CNC车床维修性水平的评价 39 ֥ሹุ࣍රඋႿޅᇕٳ҃b۴ऌҐ֥ࠢܣᅰົྩඔऌ߂ԛ֥ܣᅰྩگൈࡗඔٳ҃ೂ1෮ൕbՖᇏॖၛुԛ,ྩگൈࡗ֥ٳ҃൞၂۱ொٳ,҃ط൞ֆڂ֥bਸ਼ຓྸ؟໓ངބࣜဒ္іૼ[2~3]:ն؟ඔ౦ঃ༯,ົྩൈࡗӯؓඔᆞٳ҃,ၹՎॖࡌഡھඔ॥ӚԵྩگൈࡗඔऌٳູ҃ؓඔᆞٳ҃b2 ଆ֥ҕඔܙ࠹1 ඔ॥ӚԵܣᅰྩگൈࡗඔٳ҃ҐႨࠞնරಖمܙ࠹ྩگൈࡗٳ҃ҕඔbഡႵ၂ FrequencynumbersofrepairtimeofCNClathesটሱؓඔᆞٳ҃ሹุ֥ဢЧ{t1,t2, ,tn},ఃᇏt1,t2, ,tnູඔ॥ӚԵྩگൈࡗ֥nՑ৫ܴҳᆴ,ᄵఃරಖݦඔູ:nn2(lnti- )L[t; , ]= f(ti)= 1exp-i=12 2(1)i=1ti2 ؓඔරಖݦඔູ:nnn(lnti- 2)lnL[t; , ]=- lnti-ln(2 2)- i=12i=12 2(2)რlnL(t; , )ቋն֥ ࠣ 2,ٳљlnLؓ ࠣ 2֥ொ֝ඔ,ѩఃູਬ֤:n lnL-2(lnt = i- )(-1)/(2 2)=0i=1n(3) lnLn2 2(lnti- )/(2 4)=02 2+ 2=-2 i=1ࢳᆭѩ߄ࡥ,֤:n ^1=n lntii=1(4)n ^2=1n 2(lnti- ^)i=1ࡼဢЧܴҳᆴսೆഈൔ,֤ࠧ:^ = ^2= ଆ֥ކႪ؇ဒކႪ؇ဒ൞؇ਈܴҳᆴ֥ٳ҃აކંٳ҃ᆭࡗژކ֥ӱ؇,Ч໓ҐႨॏغۢઌڏ ථغઌڏ(K S)ဒمࣉྛࡌഡဒbK Sဒم൞ࡼn۱൫ဒඔऌοႮཬ֞ն֥Ցஆਙ,۴ऌࡌഡ֥ٳ҃,࠹ෘૄ۱ඔऌؓႋ֥ંٳ҃ݦඔF0(xi),ࡼఃაࣜဒٳ҃ݦඔFn(xi)ࣉྛбࢠ,ఃᇏҵᆴ֥ቋնधؓᆴູࠧဒ࠹ਈDn֥ܴҳᆴbࡼဒ࠹ਈDn֥ܴҳᆴაਢࢸᆴDn, ࣉྛбࢠ,ડቀ༯ਙ่ࡱ,ᄵࢤ൳ჰࡌഡ,ڎᄵऋधჰࡌഡbDn=sup|Fn(x)-F0(x)|=max{di} Dn, (5)- <x<+ ൔᇏF0(x)ູჰࡌഡؓඔᆞٳ҃ݦඔ;Fn(x)ູဢЧඔູn֥ࣜဒٳ҃ݦඔ;Dn, ູਢࢸᆴ,ॖႮਢࢸᆴDn, іҰ֤b֒n>50, =ൈ,ਢࢸᆴDn, =
40 吉林大学学报(工学版)第33卷۴ऌഈඍٚم,ࣜݖؓ൫ဒඔऌ֥ԩ,֤֞ࡌഡဒ࠹ਈDn=<D226,=,ژކဒ่֥ࡱ,ၹՎᆃඔ॥ӚԵົྩൈࡗڛՖؓඔᆞٳ֥҃ࡌഡФᆣൌb4 CNCӚԵົྩྟඣ֥ࡎ[4]ࡼܙ࠹ԛ֥ҕඔսೆؓඔᆞٳ֥҃หᆘਈݦඔіղൔ,ࠧॖ֤֞ᆃඔ॥ӚԵົྩൈࡗඔऌ֥ٳ҃ඔ࿐ଆbົྩൈࡗٳ҃ૡ؇ݦඔູ:2m1(t)=2 exp-(lnt+) ົྩ؇ݦඔ:ູM(t)= tm(lnt+)(t)dt=0 t1exp-2dt02 ົྩੱݦඔ:ູ1(lnt+)exp-22 m(t)2 (t)=1-M=(t2t)1t+)1- 02 exp-(ln ࠎႿົྩྟหᆘݦඔіղൔ֤ԛົྩྟหᆘਈ,ࣼॖၛࡎඔ॥ӚԵ֥ົྩྟඣbົྩྟᆷѓᇶေႵनົྩൈࡗMTTR(MeanTimetoRepair)aቋնົྩൈࡗބົྩൈࡗᇏᆴ(1)नົྩൈࡗMTTRनົྩൈࡗMTTR൞ᆷஆԢ၂Ցܣᅰ෮ླົྩൈࡗ֥नᆴ,MTTR֥ંٳ༅ᆴ൞ົྩൈࡗ֥नᆴࠇඔ࿐௹ຬ,ࠧ: MTTR= t m2(t)dt=exp[ ^+ ^2/2]=exp[+ (2)ቋնົྩൈࡗቋնົྩൈࡗ൞ᄝ۳ק֥Ϥٳ໊ࠇົྩ؇౦ঃ༯֥ົྩൈࡗbЧ໓౼ົྩ؇M(t)=,ᄵႵ:=exp[ + ]=exp[+ ]= (3)ົྩൈࡗᇏᆴିܔປӮົྩ۽ቔ֥50%෮ླ֥ൈࡗ,ॖၛ:֤= e=ҕॉ໓ང:[1] ඔ॥ልСࠣ༢ᇉਈ॥ᇅ щ߶ ඔ॥ልСࠣ༢ᇉਈ॥ᇅ[M].Кࣘ:ࠏྀ۽ြԛϱഠ,1997:30-35.[2]ӑ,ࣁ ࠏྀॖौྟ۽ӱ[M].Кࣘ:းࣁ۽ြԛϱഠ,1992:305.[3]ᅣݓ,ӧ๓,౩Ջ ༢ॖौྟაົྩྟ֥ٳ༅აഡ࠹[M].Кࣘ:Кࣘݴॢݴ฿ն࿐ԛϱഠ,1990:270.[4]କᇁᇑ ົྩྟഡ࠹[M].ഈݚ:ഈݚ॓࿐ඌ໓ངԛϱഠ,1990:232.
