Isikhungo esiphezulu esifile kanye nendawo ephansi efile: incazelo nokusebenza

Kumakhenikha, iphoyinti elingathathi hlangothi lihambisana nendawo yepiston ephindaphindayo kusilinda sayo. Kunezindawo ezimbili eziyizimpumputhe: i-top dead center, noma i-TDC, ne-down dead center, noma i-PMB. Phezulu endaweni efile, i-piston iphakeme ngokushaywa kwayo, kuyilapho ingaphansi kwesilinda endaweni ephansi efile. Lokhu kuhambisana nemijikelezo ehlukene yokuvutha.

🚗 Yini i-top dead center?

Ukusebenza kwenjini evuthayo yangaphakathi, njengaleyo yemoto, kusekelwe amavolovolo... Ngayinye yalezi pistons iyashelela isilinda futhi isetshenziselwa ukucindezela uphethiloli negesi ukudala ukuqhuma, amandla akho ashayela injini.

Izimoto zesimanje zifakwe injini ye-4-stroke esebenza ngemijikelezo emine ehlukene:

1. Theukungena izingxube zomoya / uphethiloli;
2. La (phoqa) le ngxube ngokuphakamisa ipiston;
3. Theukuqhuma lapho i-piston isendaweni ephakeme kakhulu;
4. Thei-échappement lapho i-piston iphakama.

Ukudala lezi zigaba ezine, ama-piston asebenza nezinye izingxenye, kuhlanganise i-crankshaft obafundisayo, kodwa futhi ama-valve okuyizingxenye ezivala umnyango wamasilinda. THE 'camshaft ivumela ukuvulwa nokuvalwa kwala ma-valve, okuvumela ukungena esigabeni sokuqala nokuphuma esigabeni sesine.

Sikhuluma ngakho enye ipiston lapho ipiston ishelela kusilinda njengephampu, njengasezinjinini ezivuthayo zangaphakathi. Kodwa-ke, endabeni yenjini ye-piston ephindaphindayo, kunamaphuzu amabili abizwa ngokuthi indawo engathathi hlangothi: isikhungo esiphezulu esifile ngakolunye uhlangothi, isikhungo esiphansi esiphansi ngakolunye.

Lezi zindawo ezifile azihlangene nokudluliselwa. Kwenzeka lokhu nje igama elithi "ukungathathi hlangothi" lathathwa ngesifaniso ukuze lisho indawo engathathi hlangothi: ngakho-ke, lesi sikhundla sisetshenziselwa ukubhekisela kulesi sikhundla se-lever yegiya, kodwa le nkulumo ibuye isetshenziswe kwezezimali.

Isikhungo esiphezulu semoto yakho, esivame ukubizwa ngokuthi i-TDC, yilapho i-piston isendaweni ephakeme kakhulu yokushaywa kwayo kusilinda. Ngakho-ke, futhi yisikhathi lapho umthamo wegumbi lomlilo uphansi kakhulu futhi ukucindezela kuphezulu kakhulu, ngaphambi nje kokushiswa kwengxube yamafutha omoya.

Kufanele wazi ukuthi inzwa ibizile Inzwa ye-PMH, unomthwalo wemfanelo wokubona lapho ipiston iphezulu endaweni efile emotweni yakho. Usebenzisa amazinyo isonto... Inzwa ye-TDC ibe idlulisela lolu lwazi ku iyunithi yokulawula injiniewusebenzisela ukuthuthukisa umjovo kaphethiloli futhi uzuze amandla omlilo ogcina injini yakho isebenza.

🔍 Yini i-bottom dead center?

Le isikhungo esiphezulu sokufa (TDC) ibhekisela esikhathini lapho ipiston yenjini evuthayo yangaphakathi isendaweni ephakeme kakhulu kusilinda lapho ukucindezela kusezingeni eliphezulu. Futhi ngokuphambene, I-Mort Bas Point (PMB) ihambisana nesikhathi lapho ipiston isendaweni ephansi kakhulu yokushaywa kwayo.

Ngalesi sikhathi, umthamo wekamelo lomlilo likhulu kakhulu: lokhu kungukuphela kokuthatha, okuwukuncela emoyeni kanye nophethiloli, inhlanganisela ezokwenza ukuqhuma nokuvutha kwenjini. Ukuminyanisa kuncane ngokwemvelo njengoba kumayelana nokudala ingxube, hhayi ukuyicindezela ukuze iqhume.

📍 Ungasithola kanjani isikhungo esiphezulu sokufa?

Isikhungo esiphezulu esifile sikhombisa indawo ephakeme kakhulu yepiston kusilinda sayo. Kodwa futhi inokunye okuwusizo: ukwazi isikhundla sesikhungo esiphezulu esifile sivumela ambambe ukusatshalaliswa, okudingekayo ekungeneleleni okuthile kwemishini enjinini.

Imoto yakho ivamise ukuba nayo izimpawu zendawo kulesi silungiselelo, kodwa ngezinye izikhathi udinga ukuthola isikhungo esiphezulu esifile ukuze uzimake wena. Kulokhu, qala injini ngesandla amajika ambalwa. Kufanele unqume indawo lapho ipiston ingaphezulu kwesilinda ngaphambi nje kokuba iqale ukwehla: lesi yisikhungo esiphezulu sokufa.

Manje uyazi ukuthi i-top dead center (TDC) kanye ne-bottom dead center (PMB) zimeni. Njengoba usuvele uqonda, lezi yizikhundla ezimbi kakhulu ze-piston ku-cylinder yayo. Kufanele futhi uqaphele ukuthi awasoze ama-piston amabili azoba sesigabeni esisodwa ngesikhathi sokusha.