Ekitondekamaanyi (Engine)

Okusinziira ku Charles Muwanga , "ekitondekamaanyi" (Engine)kiva mu bigambo by'oluganda bibiri:

(a)Okutondeka(to produce, to create)

(b)Amaanyi(Power)

Mu luganda olwa sayansi, ekikolwa eky’okutondeka kifundiwazo ky’ekigambululo “okutonda ebikoleka”. Ekikolwa eky’okutonda kya Katonda yekka era ye yekka asobola okutonda ebintu nga obwengula oba obulamu. 

Omuntu ky’akola kwe kukozesa eby’obugagga eby’ensibo Katonda bye yatonda okukola ebikozesebwa nga ennyanguyirizi n’ebyamaguzi eby’enjawulo, ekiyitibwa okutonda ebikoleka oba “okutondeka” (to produce, to manufacture).

“Okutondeka” n’olwekyo kivvuunulwa, “manufacturing, production, oba creation of goods, etc”. Omutondesi ye “manufacturer” oba producer so ng’ate omutonzi ye Katonda. Mu nnyanguyirizi enzibuwavu nga ey’ekidduka, “ekitondekamaanyi” (engine) ky’ekitundu ekikola amasoboza (energy) agavaamu amaanyi (power) agasobozesa ekidduka okutambula.

Singa oli akugamba mu Lungereza nti ‘the engine of our economy is agriculture”, kino oba okivvuunula otya mu Luganda? Osobola okukivvuunula nti “ekitondekamaanyi ky’ebyenfuna yaffe by’ebyamalimiro”.

Ekitondekamaanyi (engine) oba ekitondekamaanyi eky'amasannyalaze (motor), eba nnyanguyirizi (machine) ekozesebwa okukyusa amasoboza (energy) okugafuula “omugendo’ (movement). Amasoboza gayinza okubeera mu mbeera yonna. Amasoboza agasinga okukozesebwa mu bitondekamaanyi galimu amasannyalaze, ag’ekika eky'enkyusabuziba  nga petulooli oba ddizero, oba okwokya (heat). Kemiko bw’eba ekozeseddwa okutondeka amasoboza, eyitibwa mafuta (fuel).

Enjawulo wakati w’ekitondekamaanyi (engine) n’ekitondekamaanyi eky'amasannyalaze (motor) eri mu kuba nti ekitondekamaanyi kitondeka “amasoboza ag’ekitambuzo” (mechanical energy) okuva mu bwoki (heat) so nga ate “ekitondekamaanyi eky'amasannyalaze” (motor) kitondekawo amasoboza ag’ekitambuzo okuva mu bika by’amasoboza ebirala ng’amasannyalaze. 

Ebitondekamaanyi byennyini biba bitondekamaanyi eby’omukka gw’amazi (steam) n’kitondekamaanyi eky’entabamuliro ey’omunda (internal combustion engine) kyokka ensoboza (motor) zennyini zirimu ensoboza ey’amasannyalaze (electric motor) n’ensoboza etambuzibwa amazzi (hydraulic motor).

Ku mulembe guno ekitondekamazzi kinnyonnyola ennyanguyirizi nga ebitondekamaanyi eby’omukka gw’amazi (steam engine), n’ebitondekamaanyi eby’entabamuliro eyo munda (internal combustion engines), ebyokya oba ka tugambe nti bikozesa amafuta okuikola emirimu egy’ekitambuzo (mechanical work) nga giteeka empalirizo ey’omugendo omugolokofu (torque) eyitibwa “ekisukuma” (thrust). 

Eky’okulabirako ky’ebitondekamaanyi ebikola "empalirizo ey’omugendo" (torque) mulimu ebitondekamaanyi ebya bulijjo ebya gasoliini ne ne dizero n’ebibongolo eby’empujjo (turboshafts). Eky’okulabirako ky’ebitondekamaanyi ebitondeka ekisukuma (thrust) mulimu ebiwujjo eby’empujjo (turbofans) n’ebizungirizi (rockets).

Ekitondekamaanyi(engine) y'ennyanguyirizi(machine) ekozesa amasoboza ag’amafuta okutambuza   ebitundu byayo. Kino  kigeraageranye n'ekitondekamaanyi eky'amasannyalaze(morta) . Mota  ekozesa maanyikasoboza  agatali ga mafuta ,  naddala ag’amasannyalaze okutambuza  ebitundu byayo. 

 Motoka ziba n'ebitondekamaanyi ebyakira ku mafuta  oba ku masannyalaze. Ekitondekamaanyi kye kikola amasoboza ag’etaagisa okusobozesa motoka okuva mu kifo n’etambula . Ebitondekamaanyi  ebitonoko bitera okuba n’amaanyi matonoko olw’okuba nga bifulumya amasoboza(energy) matonoko .Ekitondekamaanyi kikola amasimbula(torque) , amaanyi agajja emmotoka mu kifo w’ebadde eyimiridde ate n’ekola amaanyi g’endogoyi(horse power) , amaanyi agakozesebwa emotoka ng’eri mu mugendo. 

Ekigendererwa ky'ekitondekamaanyi ky’emotoka kwe kukola amasoboza(energy) agasobola okutambuza emotoka.Engeri esingayo obwangu okutambuza emotoka ng’okozesa amafuta nga gasoliini(gasoline) kwe kwokya amafuta gano gennyini agali munda mw'ekitondekamaanyi . N’olwekyo ekitondekamaanyi ky’emotoka ,  “ekitondekamaanyi  ekitabira munda ”( internal combustion engine ) kubanga  entabamuliro( combustion) agenda mu maaso munda mwa kitondekamaanyi .Osaana okimanye nti:

•	Waliwo ebitondekamaanyi ebitabiramunda eby'enjawulo: waliwo ebya dizero n’ebya ggaasi (gas turbine engines).Bino era biyitibwa bitondekamaanyi ebya nattabikiramunda
  
•	Waliwo ebitondekamaanyi ebitabirabweru (external combustion engine) .Ekyokulabirako eby'ebitondekamaanyi eby’omukka gw’amazzi(steam engines)  mu ggaali z’omukka ezasooka n’amaato ag’omukka gw’amazzi(steam boats). Wano amafuta(amanda oba enku, woiro, n’ebika ebirala) gokyebwa wabweeru w'ekitondekamaanyi okukola omukka ogw'enfuumo(steam) olwo enfuumo n’ereetawo omugendo munda mu kitondekamaanyi.

•	Ekitondekamaanyi ekya nattabikiramunda kikola bulungi okusinga ekya nattabikira bweeru era ekozesa amafuta matono nnyo buli mairo ate era eba ntono nny o. Emmotoka okusobola okukola erina okuba n’ensengekera(systems) zino:

Ebitondekamaanyi eby’Enkunu (Piston engines).

Muno amafuta gokyebwa wansi mu ntobo y’ekisituliro (tray) era omukka gw’amazzi gukolebwa mu kibugumizo (boiler) ebiteeka empalirizo ku kibongolo (crankshaft) ne kireetera namuziga nayo okwetoloola ekiviirako emotoka okutambula.

Ebitondekamaanyi ebyasooka byakozesanga obwoki (heat) obwavanga wabweru w’ekitondekamaanyi ne byokyesa ggaasi ku kanyigirizi aka waggulu (high pressure) Bino byalinga bitondekamaanyi bya mikka gwa mazzi (steam) era ebitondekamaanyi ne biyiotibwa bitondekamaanyi bya mukka (Steam engines). 

Omukka gw’amazzi ogwokya gwawerezebwanga mu luseke okuyingira ekitondkamaanyi okusobola okuteeka empalirizo ku nkunu (pistons) okuleetawo okuva. Ebitondekamaanyi bino byakozesebwanga mu makolero amakadde, amaato n’emmeeri. Manya nti omukka gw’amazi agookya ye steam ate enfuuma eva mu kufumuuka kw’omukka guno ye vapour).

Ebitundu by’ekitondekamaanyi ebisookerwako.

Entabiro y’ekitondekamaanyi y’enkinu (cylinder)s, enkunu (piston) mwe zebongera okuva wansi okudda waggulu munda mw’enkinu. 

Walwo ebitondekamaanyi bya njawulo. Waliwo ekitondeka maanyi eky’enkinu emu one cylinder engine nga mu nyanguyiriza ezisaawa omuddo. Emotoka ezisinga zirina enkiinu ezisukka mu emu, ezimu enkulunnya, mukaaga, n’endala enkinu munaana.

Mu kitondekamaanyi eky’enkimu ennyingi (multi-cylinder engine) enkulu zisengekeddwa mu emuku ngeri esatu; lunyiriri (in a line) mu nkula eya – V, n’okugalamivu (horizontal).Bino by’ebitundu by’ekitondeka maanyi.
	

(i)	Ekikubansasi oba Ekikoleezo ky’ensasi (spark plug)

“Ekikuba nsasi oba ekikoleezo ky’ensansi kye kivaamu ensasi (spark) ekoleeza omugattiko gw’empewo n’amafuta okusobozesa entabamuliro (combustion) okubaawo. Ensasi (spark) erina okubaawo mu kasera kennyini akatuufu ekintu  okutabuka obulungi.

(ii)	Obwebunizo (valves)

Obweburizo obubuyimiriza n’okufulumya bweggala mu kaseera aketaagisa okuyingiriza empewo n’amafuta n’okufulumya omukka ogwa kazambi. Manya nti obwebarizo bwombi bweggala mu kinyigurrizo ky’empewo n’amafuta mu kikalwa eky’entabamuliro/ nattabulamuliro okusobola okulaba nga ekisenge ky’entabamuliiro kyonna kiggude.

(iii)	Enkunu  (Piston)

Wali olabye ekinu ekiganda bwe kifaanana? Kiba nga mukebe omwetoloovu nga entobo ebbiri ezigendagana nnetoloovu. Enkula ey’ekinu n’olwekyo mu bufunze kifuuka enkinu, kino nga kilaga enkula ey’ekinu ng’ogitunuulidde okuva munda oba enkunu, enkula ey’ekinu ng’ojitunuulidde okuva ku ngulu kwayo.

Enkunu kintu ekyakula ng’ensamu ekozesebwa mu kukomaga naye nga yo ya kyuma. Enkunu yebonga ng’edda wansi ne waggulu munda mw’enkinu (inside the cylinder). Ekyebongolo nkalubo ya kyuma ey’enkumu (cylindrical method) eyeboonya ny’edda wansi ne waggula munda mw’enkinu (cylinder).

(iv)	Obukugiro  by’enkunu  (piston rings)

Akakugiro k’enkunu (piston rings) kakola okusiba wakati w’ebisenge by’enkinu n’enkunu). Obukugiro (rings) bulina ebigendererwa bibiri.

a)	Okukugira oba okuziiyiza ekintabuli ky’amafuta n’empewo mu kisenge ky’entabamuliro (combustion chamber) obutawaguza kutonnya mu kiterekero kya woyiro (ekiteroyiro=sump) ng’ekikkatiro n’entabamuliro bigenda mumaaso.

b)	Okukuumira woyiro mu kiteroyiro (sump) obutatonnya mu kisenge ky’entabamuliro (combustion chamber) kuba woyiro awo aba ajja kwokyebwa afe ttayo.
Emookoka ezisinga ezokya woyiro ziba n’ ebitodekamaanyi (egine) ebikaddiye era ng’obukugiro tebukyaziyiza bulungi woyiro butatonnya.

(v)	Akakono (connecting rod)

“Akakono” (connecting rod) kakwataganya enkunu (piston) ku kyebongolo (crankshaft), ekyebonga ne kikola omugendo ku namuziga eya mutebentusa (flywheel). Akakono ketoloolera ku nkomerero zombi okusobozesa epeto lyako okukyuka buli nkunu lw’etambula ate ekyebongolo ne kyetoloola.

(vi)	Ebyebongozo engeri gye bikolamu (How cam shafts work)

Omanyi nti waliwo obwebunizo (valves), obuyingiza ekintabuli ky’empewo n’amafuta n’okufulumya kazambi w’amafuta agoogokeddwa okuva mu kitondekamaanyi.
Ekyebongozo kyeyambisa obukukunavu obuyitibwa “engozo” (cams) obwesindika ku bwebunizo okubuggula nga ekyebongozo bwe kyebonga (rotate up and down), seppulingi ku bwebunizo ze zizza obwebindu (engozo) mu mbeera yabwo ey’okubunira.

(vii)	Ekyebongolo (crankshaft)

Ekyebongolo kiva mu kikolwa kya kwebonga kwa nkunu ng’eva wansi n’edda waggulu mu nkinu era ekyebongolo kino kikyusa omugendo gw’enkinu ogwa wansi ne waggulu ne gufuuka omugendo ogwetoloola. 

(viii)	Ekiteroyiro (Sump).

Bwe njogera ku kiteroyiro (sump) mba ntegeeza ekitereka oyiro. Ekiteroyiro kyebulungudde ekyebolongodlo era mu ntobo yakyo mukungaaniramu woyiro ow’ekigero. 
Obuzimbe n’enkola y’ekitondekamaanyi (Structure and principle of engine).

Waliwo ebitondekamaanyi bya ngeri nyingi omuli:

a)	Ekitondekamaanyi eky’omukka gw’amazi.

b)	Ekitondekamaanyi eky’empewo eyokya.

c)	Ekitodenkamaanyi ekyasisa ensasi (spark ignition engine).

d)	Empujjo ez’omukka ogwokya (steam turbine).

e)	Ekitondekamaanyi ekikokeezebwa ekinyigirizo (compression ignition engine).

f)	Empujjo eya ggasi (gas turbine).

g)	 Ekitodenkamaanyi eky’ekizungirizi (rocket engine

h)	Ekitondekamaanyi eky’omukka (steam engine).