Ezinjinini ezivuthayo, kokubili ukonga uphethiloli kanye nokwelashwa kwegesi yokukhipha amandla ngeke kwenzeke ngaphandle kokuba khona kwe-lambda probe. Ngenxa yalezi zinzwa, ukungcola kwenjini kuncipha kakhulu futhi kuyathandeka ukukusebenzisa.
I-lambda probe, eyaziwa nangokuthi inzwa ye-oxygen, inomsebenzi wokulinganisa umehluko phakathi kokuqukethwe komoyampilo kwamagesi akhipha umoya kanye nokuqukethwe komoyampilo endaweni ezungezile.
Le nzwa ikweleta igama layo ngohlamvu λ (lambda) kusukela kuzinhlamvu zamagama zesiGreki, ezisetshenziselwa ukumela ukulingana phakathi kwenani langempela likaphethiloli womoya kanye nesilinganiso esithathwa njengesihle (noma se-stoichiometric) sengxube. Lapho inani lingaphansi kokukodwa ( λ ) kusho ukuthi inani lomoya lingaphansi kokuhle, ngakho-ke ingxube inothile. Lapho kwenzeka okuphambene ( λ > 1 ), ngokuba nomoya oweqile, ingxube kuthiwa ayilungile.
Isilinganiso esikahle noma se-stoichiometric, kusetshenziswa injini kaphethiloli njengesibonelo, kufanele sibe izingxenye zomoya eziyi-14.7 engxenyeni eyodwa kaphethiloli. Nokho, lesi silinganiso asishintshi ngaso sonke isikhathi. Kukhona okuguquguqukayo okuthinta lobu buhlobo, kusukela ezimweni zemvelo - izinga lokushisa, ingcindezi noma umswakama - ukuya ekusebenzeni kwemoto ngokwayo - i-rpm, izinga lokushisa lenjini, ukuhlukahluka kwamandla adingekayo.
I-lambda probe, ngokwazisa ukuphathwa kwe-elekthronikhi kwenjini ngomehluko wokuqukethwe komoya-mpilo kumagesi aphumayo nangaphandle, ivumela ukuthi ilungise inani likaphethiloli elijovwe egunjini elivuthayo.
Inhloso ukuzuza ukuvumelana phakathi kwamandla, ukonga kukaphethiloli kanye nesisi esikhishwayo, okuletha ingxube eduze ngangokunokwenzeka ebudlelwaneni be-stoichiometric. Ngamafuphi, ukwenza injini isebenze ngokuphumelelayo ngangokunokwenzeka.
Isebenza kanjani?
I-lambda probe isebenza ngempumelelo kakhulu emazingeni okushisa aphezulu - okungenani angu-300 °C - okunqume ukuthi indawo yayo ekahle iseduze nenjini, eduze nje kwama-nifold exhaust. Namuhla, ama-lambda probes angatholakala eduze kwe-converter ye-catalytic, njengoba anokumelana okuvumela ukuba ashise ngaphandle kokushisa kwegesi yokukhipha.
Njengamanje, izinjini zingaba nama-probe amabili noma ngaphezulu. Njengesibonelo, kunamamodeli asebenzisa ama-lambda probes atholakala ngaphambi nangemva kwe-catalyst, ukuze alinganise ukusebenza kahle kwalesi sici.
I-lambda probe yenziwe nge-zirconium dioxide, i-ceramic material okuthi uma ifinyelela ku-300 ºC ibe i-conductor yama-ion oksijini. Ngale ndlela, i-probe iyakwazi ukukhomba ngokushintshashintsha kwamandla kagesi (okukalwa nge-mV noma ama-millivolts) inani le-oxygen elikhona kumagesi akhipha umoya.
I-voltage efika cishe ku-500 mV ikhombisa ingxube ethambile, ngaphezu kwalokho ikhombisa imiksi ecebile. Yile signali kagesi ethunyelwa eyunithi yokulawula injini, futhi eyenza ukulungiswa okudingekayo enanini likaphethiloli elifakwe enjinini.
Kukhona olunye uhlobo lwe-lambda probe, oluthatha indawo ye-zirconium dioxide nge-semiconductor esekelwe ku-titanium oxide. Lokhu akudingi ireferensi yokuqukethwe komoya-mpilo okuvela ngaphandle, njengoba kungashintsha ukumelana kwawo nogesi kuye ngokugxila komoyampilo. Uma kuqhathaniswa nezinzwa ze-zirconium dioxide, izinzwa ezisekelwe ku-titanium oxide zinesikhathi esifushane sokuphendula, kodwa ngakolunye uhlangothi, zizwela kakhulu futhi zinezindleko eziphezulu.
Kwakuyi-Bosch eyasungula uphenyo lwe-lambda ngasekupheleni kwawo-1960 ngaphansi kokuqondisa kukaDkt. Günter Bauman. Lobu buchwepheshe baqala ukusetshenziswa emotweni yokukhiqiza ngo-1976, kuVolvo 240 no-260.
Amaphutha namaphutha amaningi.
Kulezi zinsuku, i-lambda probe ayinalo igama elihle kakhulu, nakuba isidingo sayo singenakuphikiswa. Ukushintshwa kwayo, ngokuvamile okungadingekile, kuvela kumakhodi ephutha akhiqizwa ukuphathwa kwe-electronic injini.
Lezi zinzwa zimelana kakhulu kunalokho ezivela kuzo, ukuze kuthi, noma kuvela amakhodi amaphutha ahlobene ngqo nazo, zingavela kwenye inkinga ekuphathweni kwenjini, zikhombisa ukusebenza kwenzwa. Njengesexwayiso kanye nokuxwayisa ngokungasebenzi kahle kwezimoto okungenzeka, abaphathi benjini kagesi bakhipha iphutha lenzwa.
Esimeni sokushintshisana, kuhlale kuwumqondo omuhle ukukhetha izingxenye zangempela noma ezaziwayo zekhwalithi. Ukubaluleka kwale ngxenye kubalulekile ekusebenzeni kahle nempilo yenjini.