Isikhathi se-valve esiguquguqukayo. Inikeza ini futhi inenzuzo
Uhlelo lokusabalalisa igesi ludlala indima ebalulekile ekusebenzeni kwanoma iyiphi injini. Isistimu yesikhathi se-valve eguquguqukayo isiye yaba yinto ehamba phambili eminyakeni yamuva. Lenzani?
Isistimu yesikhathi se-valve (evame ukwaziwa ngokuthi ukusatshalaliswa kwegesi) inesibopho sokuhlinzeka ngengxube ecindezelwe, okungukuthi ingxube kaphethiloli-yomoya, kusilinda kanye nokukhipha amagesi okukhipha umoya emigudwini yokukhipha umoya.
Izinjini zesimanje zisebenzisa izinhlobo ezintathu eziyinhloko zesikhathi se-valve: i-OHV (i-camshaft engaphezulu), i-OHC (i-camshaft engaphezulu), ne-DOHC (i-camshaft engaphezulu kabili).
Kodwa ngaphandle kwalokhu, isikhathi singase sibe nesistimu yokusebenza ekhethekile. Enye yezinhlelo ezivame kakhulu zalolu hlobo amasistimu wesikhathi se-valve aguquguqukayo.
ISIVUMELWANO
Ukushisa okuphezulu
Isikhathi se-valve esiguquguqukayo sasungulwa ukuze kutholwe amapharamitha angcono omlilo ngenkathi kuthuthukiswa amandla. Abanye bazothi sekuyisikhathi eside kwaziwa ukuthi i-turbocharging inikeza ukugeleza okuhle kwamandla.
Kodwa-ke, ukushaja okuphezulu kuyisixazululo esibiza kakhulu esishiya ukonga kukaphethiloli ngemuva. Khonamanjalo, abaklami bebefuna ukunciphisa ukusetshenziswa kukaphethiloli. Lokhu kwenziwa ngokusetha i-engeli yokuvula ye-valve eyodwa noma enye kuye ngesivinini senjini ngaleso sikhathi, kanye namandla okucindezela i-pedal ye-accelerator.
- Namuhla lesi sixazululo siyasetshenziswa kakhulu kuyo yonke imiklamo yesimanje. Ihlinzeka ngokugcwaliswa okungcono kwamasilinda ngengxube yamafutha omoya uma kuqhathaniswa nezisombululo ezijwayelekile, ezakhelwe kahle ukuthi zihambisane nesivinini nomthwalo wenjini, kusho uRobert Puchala weqembu leMotoricus SA.
Bheka futhi: Ingabe kufanele ubheje ngenjini kaphethiloli ene-turbocharged? I-TSI, T-Jet, EcoBoost
Isistimu yokuqala ye-valve yesikhathi esishintshayo yavela ngo-1981 ku-Alfa Romeo Spider. Kodwa kuphela ukwethulwa kwalolu hlelo (emva kokuthuthukiswa) ngabakwaHonda ngo-1989 (uhlelo lwe-VTEC) kwaphawula ukuqala komsebenzi womhlaba wesistimu yesikhathi se-valve eguquguqukayo. Ngokushesha kwavela izinhlelo ezifanayo kwaBMW (Doppel-Vanos) kanye neToyota (VVT-i).
A little ofory
Okokuqala, ake siqonde leli gama elididayo - ukushintsha isikhathi se-valve. Sikhuluma ngokushintsha izikhathi zokuvula nokuvala ama-valve kuye ngomthwalo wenjini nesivinini sayo. Ngakho-ke, isikhathi sokugcwalisa nokukhipha isilinda ngaphansi komthwalo siyashintsha. Isibonelo, ngesivinini esiphansi senjini, i-valve yokudonsa ivuleka kamuva futhi ivaleke ngaphambi kwesikhathi kunesivinini esiphezulu senjini.
Umphumela uba ijika le-torque eliyisicaba, okungukuthi i-torque eyengeziwe itholakala nge-rpm ephansi, okwandisa ukuguquguquka kwenjini ngenkathi kunciphisa ukusetshenziswa kukaphethiloli. Ungakwazi futhi ukubona impendulo engcono yokucindezela i-pedal yegesi kumayunithi ahlonyiswe ngesistimu enjalo.
Kuhlelo lwezikhathi ze-valve lwe-Honda VTEC olusetshenziswa ngeminyaka yama-90s, amasethi amabili wamakhamera ama-valve atholakala ku-shaft. Bashintsha ngemva kokudlula i-4500 rpm. Lesi simiso sisebenza kahle kakhulu ngesivinini esiphezulu, kodwa sibi nakakhulu ngesivinini esiphansi. Ukushayela imoto exhaswe yilesi simiso kudinga ukushintshwa okunembile.
Kodwa umsebenzisi unemoto enenjini engaba ngu-30-50 hp. enamandla kakhulu kunamayunithi anevolumu efanayo yokusebenza ngaphandle kokushintsha isikhathi se-valve. Ngokwesibonelo, Honda 1.6 VTEC injini ukhiqiza 160 hp, futhi inguqulo yesikhathi standard - 125 hp. Uhlelo olufanayo lwenziwe ngabakwaMitsubishi (MIVEC) kanye nabakwaNissan (VVL).
Isistimu ye-i-VTEC ethuthukisiwe yakwaHonda ikwazile ukuthuthukisa ukusebenza kwenjini kumarevs aphansi. Umklamo uhlanganisa amakhamera ku-shaft nesistimu ye-hydraulic evumela ukuthi uguqule ngokukhululekile i-angle ye-camshaft. Ngakho-ke, izigaba zesikhathi se-valve zashintshwa kahle ukuze zihambisane nesivinini senjini.
Ukufundwa okufanelekile: Uhlelo lwe-exhaust, isiguquli se-catalytic - izindleko nokuxazulula izinkinga
Izixazululo ezincintisanayo i-VVT-i kumamodeli akwaToyota, i-Double-Vanos kuBMW, iSuper Fire e-Alfa Romeo noma iZetec SE kwaFord. Izikhathi zokuvula nezokuvala zama-valve azilawulwa ngamasethi amakhamera, kodwa nge-hydraulic phase shifter ebeka i-angle ye-shaft lapho amakhamera atholakala khona. Amasistimu alula anama-engeli e-shaft angashintshi ashintsha nge-RPM. Ezithuthuke kakhulu zishintsha i-engeli kahle.
Vele, amasistimu wesikhathi se-valve aguquguqukayo ayatholakala nakweminye imikhiqizo eminingi yezimoto.
Izinzuzo nokungalungi
Sesike sazisho izinzuzo zezinjini ezifakwe i-variable valve timeing system ngenhla. Lokhu wukuthuthukiswa kokuguquguquka kweyunithi yamandla ngenkathi kuthuthukiswa ukusetshenziswa kukaphethiloli. Kodwa cishe njenganoma iyiphi indlela, isistimu yesikhathi se-valve eguquguqukayo nayo inobubi.
“Lezi zinhlelo ziyinkimbinkimbi, zinezingxenye eziningi, futhi uma kwenzeka zihluleka, ukuzilungisa kunzima, okuhambisana nezindleko ezinkulu,” kusho u-Adam Kowalski, umakhenikha waseSłupsk.
Ngisho nasendabeni yokulungisa ibhande lesikhathi esivamile, izindleko zokulungisa zingadlula izinkulungwane ezimbalwa ze-zł. Kufanele futhi kucatshangelwe ukuthi ngeke silungise isistimu yesikhathi se-valve eguquguqukayo kunoma iyiphi i-workshop. Ngezinye izikhathi kuhlala kuphela ukuvakashela isikhungo sesevisi esigunyaziwe. Ngaphezu kwalokho, ukunikezwa kwezingxenye ezisele akunzima kakhulu.
- Okubi nakho kuyizindleko zokuthenga imoto ngokwayo, ngisho nasemakethe yesibili. Ahlala ebiza kakhulu ngamashumi, futhi ngezinye izikhathi amashumi amaningana amaphesenti, kunozakwabo ngaphandle kokushintsha isikhathi se-valve, umakhenikha uyanezela.
I-Turbo emotweni - amandla amaningi, kodwa inkathazo eyengeziwe. Umhlahlandlela
Ngakho-ke, ngokombono wakhe, umuntu udinga imoto yedolobha kuphela, akunakwenzeka ukuthi kuzokwazi ukusizakala ngemoto enenjini ene-valve eguquguqukayo. U-Adam Kowalski uthi: “Amabanga edolobha mafushane kakhulu ukuba angajabulela ukuhamba kwezimoto nokusebenzisa uphethiloli ngendlela efanele.
I-Mechanics iluleka, ukuze ugweme imiphumela engathandeki kanye nezindleko ezinkulu ngemuva kokuhluleka kwe-valve, imithetho eminingana ejwayelekile kufanele igcinwe.
“Uma sithenga imoto eke yasetshenziswa singenaso isiqiniseko ngomlando wayo wokusebenza, kumele siqale sishintshe ibhande le-timing sifake ama-tension kanye nepompo yamanzi, vele, uma ishayelwa ibhande,” kusho uRobert Puchala wakwaMotoricus SA. Iqembu.
