VVT ndiyo chidimbu cheChirungu cheVariable Valve Timing. Iyo camshaft yekamshaft yeinjini yechinyakare yakagadziriswa, inowiriraniswa nechikamu cheinjini crankshaft, ndiko kuti, kuvhura nekuvhara kona (nguva) pakati pevharuvhu yekupinda uye vheji yekuburitsa haichinji.

Naizvozvo, zvakanakisa Zvakaoma kuwana yakanakisa kukurumidza-kumhanya kuita panguva imwe chete neiyo yakaderera-speed valve timing ye ", ndiko kuti, hazvibviri kuenzanisa zvinodiwa zvekumhanya-mhanya kugadzikana, kuderera-kumhanya torque kubuda. uye high-speed kubuda. Kuti ugadzirise zvinodikanwa zvakasiyana zveinjini yenguva yevharuvhu mukumhanya kwakanyanya uye yakaderera spidhi renji, inoshanduka yevhavha nguva (VVT) system inogamuchirwa. Iyo hydraulic actuator (VVT phaser) yakaiswa kumberi kwekamshaft, uye iyo hydraulic pressure inodzorwa nemagetsi. Nzira dzekushandura chikamu che camshaft maererano ne crankshaft kuti uenderere mberi kana kudzoreredza nguva yevhavha. Iyo VVT phaser uye camshaft musangano inoratidzwa mumufananidzo uri pazasi.

Parizvino, injini dzepeturu dzakawanda dzakashongedzerwa nemhando dzakasiyana dzeVVT masisitimu. Kunyanya kumainjini ane epamusoro emission standard, iwo akashongedzerwa neaviri VVT masisitimu (yekupinza uye exhaust camshafts akashongedzerwa neVVT phasers). Muchokwadi, iyo VVT system inosangana nezvinodiwa zveakasiyana mamiriro ekushanda uye inowana inoenderana tekinoroji zviratidzo nekushandura iyo valve overlap angle. Kazhinji, ine zvinotevera zvakanakira:

(1) Chikamu chekutora uye kubudisa camshafts inogona kugadziriswa, iyo inogona kuwedzerwa kuburikidza nemutemo. Ivhavha inopindirana angle inowedzera injini yemhepo.

(2) Deredza iyo yakasara yekupedza gasi coefficient uye uvandudze kunyatsochaja.

(3) Kuvandudza injini simba uye torque, uye zvinobudirira kuvandudza hupfumi hwemafuta.

(4) Zviripachena kunatsiridza iyo isingaite yekumhanyisa kugadzikana, nekudaro kuwana nyaradzo uye kuderedza kuburitswa.