Canjin lokaci bawul. Me yake bayarwa kuma yana da riba

Tsarin rarraba iskar gas yana taka muhimmiyar rawa a cikin aikin kowane injin. Tsarin lokaci mai canzawa na bawul ya zama abin bugu a cikin 'yan shekarun nan. Me yake yi?

Tsarin lokaci na bawul (wanda aka fi sani da rarraba iskar gas) yana da alhakin samar da cakuda mai matsa lamba, watau man fetur-iska cakuda, zuwa silinda da kuma fitar da iskar gas a cikin wuraren da aka fitar.

Injunan zamani suna amfani da manyan nau'ikan lokaci na bawul: OHV (camshaft sama), OHC (camshaft sama da sama), da DOHC (camshaft sama da sama biyu).

Amma banda wannan, lokacin yana iya samun tsarin aiki na musamman. Ɗayan tsarin gama gari na wannan nau'in shine tsarin lokacin bawul mai canzawa.

ADDU'A

Mafi kyawun konewa

An ƙirƙira lokacin canzawar bawul don samun ingantattun sigogin konewa yayin inganta haɓakawa. Wasu za su ce an dade da sanin cewa turbocharging yana samar da wutar lantarki mai kyau.

Koyaya, supercharging shine mafita mai tsada mai tsada wanda ke barin tattalin arzikin mai a bango. A halin yanzu, masu zanen kaya sun so su rage yawan man fetur. Anyi hakan ne ta hanyar saita kusurwar buɗewa na ɗaya ko wata bawul ɗin dangane da saurin injin ɗin a halin yanzu, da kuma ƙarfin latsa bugun bugun bugun.

- A zamanin yau ana ƙara yin amfani da wannan maganin a cikin duk ƙirar zamani. Yana ba da mafi kyawun cika silinda tare da cakuda mai mai iska idan aka kwatanta da daidaitattun mafita, waɗanda aka tsara da kyau don matsakaicin gudu da nauyin injin, in ji Robert Puchala daga ƙungiyar Motoricus SA.

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Tsarin lokaci mai canzawa na farko ya bayyana a cikin 1981 akan Alfa Romeo Spider. Amma kawai gabatarwar wannan tsarin (bayan ingantawa) ta Honda a cikin 1989 (tsarin VTEC) ya nuna farkon aikin duniya na tsarin lokaci mai canzawa. Ba da da ewa ba irin wannan tsarin ya bayyana a BMW (Doppel-Vanos) da Toyota (VVT-i).

A bit of ka'idar

Da farko, bari mu fahimci wannan kalma mai ruɗani - canza lokacin bawul. Muna magana ne game da canza lokacin buɗewa da rufe bawuloli dangane da nauyin injin da saurin sa. Don haka, lokacin cikawa da sharewar silinda a ƙarƙashin kaya yana canzawa. Misali, a ƙananan saurin injin, bawul ɗin ci yana buɗewa daga baya kuma yana rufewa da wuri fiye da saurin injin.

Sakamakon haka shine madaidaicin jujjuyawar juzu'i, watau ƙarin juzu'i yana samuwa a ƙananan rpm, wanda ke ƙara ƙarfin injin yayin rage yawan man fetur. Hakanan zaka iya lura da mafi kyawun amsawa don danna fedar gas don raka'a sanye take da irin wannan tsarin.

A cikin tsarin lokacin bawul ɗin canji na Honda VTEC da aka yi amfani da shi a cikin 90s, saiti biyu na kyamarori na bawul suna kan shaft. Suna canzawa bayan wuce 4500 rpm. Wannan tsarin yana aiki sosai a cikin manyan gudu, amma mafi muni a ƙananan gudu. Tuƙi abin hawa mai ƙarfi da wannan tsarin yana buƙatar madaidaicin canji.

Amma mai amfani yana da mota mai injin kimanin 30-50 hp. ya fi ƙarfi fiye da raka'a tare da ƙarar aiki iri ɗaya ba tare da canza lokacin bawul ba. Alal misali, injin Honda 1.6 VTEC yana samar da 160 hp, kuma a cikin daidaitaccen lokaci - 125 hp. An aiwatar da irin wannan tsarin ta hanyar Mitsubishi (MIVEC) da Nissan (VVL).

Tsarin i-VTEC na ci gaba na Honda ya sami damar haɓaka aikin injin a ƙananan revs. Zane ya haɗu da cams akan shaft tare da tsarin hydraulic wanda ke ba ku damar canza kusurwar camshaft kyauta. Don haka, an daidaita matakan lokacin bawul ɗin bawul ɗin daidai da saurin injin.

Cancantar karantawa: Tsarin ƙyalli, mai canzawa - farashi da matsala 

Hanyoyin gasa sune VVT-i a cikin samfurin Toyota, Double-Vanos a cikin BMW, Super Fire a Alfa Romeo ko Zetec SE a cikin Ford. Lokutan buɗewa da rufewa na bawul ɗin ana sarrafa su ba ta hanyar saitin kyamarori ba, amma ta hanyar canjin lokaci na hydraulic wanda ke saita kusurwar shaft ɗin da kyamarorin suke. Sauƙaƙan tsarin suna da kafaffen kusurwoyi da yawa waɗanda ke canzawa tare da RPM. Ƙarin ci-gaba suna canza kusurwa a hankali.

Tabbas, ana kuma samun tsarin daidaita lokutan bawul akan wasu samfuran mota da yawa.

Abũbuwan amfãni da rashin amfani

Mun riga mun ambata fa'idodin injuna sanye take da tsarin lokacin bawul mai canzawa a sama. Wannan haɓakawa ne a cikin haɓakar naúrar wutar lantarki yayin inganta yawan mai. Amma kamar kusan kowace na'ura, tsarin lokaci mai canzawa shima yana da asara.

"Wadannan tsarin suna da rikitarwa, tare da sassa da yawa, kuma a cikin yanayin rashin nasara, gyara yana da wuyar gaske, wanda ke da alaƙa da farashi mai mahimmanci," in ji Adam Kowalski, makaniki daga Słupsk.

Ko da a cikin yanayin gyaran bel na al'ada na al'ada, farashin gyare-gyare na iya wuce dubun zł. Har ila yau, dole ne a la'akari da cewa ba za mu gyara tsarin lokaci na bawul ba a kowane taron bita. Wani lokaci ya rage kawai don ziyarci cibiyar sabis mai izini. Bugu da ƙari, tayin kayan gyara ba ta da yawa.

- Bangaran kuma shi ne kudin siyan motar da kanta, ko da a kasuwar sakandare. Koyaushe suna da tsada da dubun, wani lokacin kuma da yawa bisa ɗari, fiye da takwarorinsu ba tare da canza lokacin bawul ba, in ji makanikin.

Turbo a cikin mota - ƙarin iko, amma ƙarin matsala. Jagora 

Sabili da haka, a cikin ra'ayinsa, wani yana buƙatar mota kawai don birni, yana da wuya cewa zai yiwu a yi amfani da mota tare da injin tare da lokaci mai canzawa. Adam Kowalski ya ce "Nisan birni sun yi gajeru don jin daɗin kuzari da kuma amfani da mai."

Makanikai suna ba da shawara, don guje wa sakamako mara kyau da tsada mai yawa bayan bawul ɗin ya gaza, ya kamata a kiyaye ƙa'idodi na gaba ɗaya.

"Idan muka sayi motar da aka yi amfani da ita ba tare da tabbatar da tarihin sabis ɗinta ba, dole ne mu fara maye gurbin bel ɗin lokaci tare da masu tayar da hankali da famfo na ruwa, ba shakka, idan bel ne ke tuka ta," in ji Robert Puchala daga Motoricus SA. Rukuni.