SE539919C2 - A cooling system for a combustion engine and a further object - Google Patents

Abstract

The present invention relates a cooling system configured to cool a combustion engine (2) and at least one further object (18) in a vehicle (1). The cooling system comprises a main radiator (8), a main radiator bypass line (9) directing coolant past the main radiator (8), a first valve device (6) receiving coolant from the combustion engine (2) and directing it to the main radiator (8) and the main radiator bypass line (9), an auxiliary circuit (14) directing coolant to the further object (13), and a second valve device (20) receiving coolant from the main radiator (11) and/or the main radiator bypass line (9) and directing it to the auxiliary circuit (14) and/or the combustion engine (2). The auxiliary circuit (14) comprises an auxiliary radiator (15) in which the coolant is cooled to a lower temperature than in the main radiator (8), and an auxiliary heat exchanger (23) located downstream of the auxiliary radiator (15) in the auxiliary' circuit (14). The coolant is heated in the auxiliary heat exchanger (23) by coolant in an engine outlet line (5) before it is directed to the combustion engine (2).

Description

ti) “H5 2D A eeoiing sftfstent ter' a eernhnstien engine and a further object iíšAíÄfïKíšRíïši/ENI) ÛF 'THE ÉNNfEElNTFEON ANiD PRiÛiš_ ARÄE' 'the present inveintioii reiates te a eeeiing systern ter a eetnhiistitän engine anti a tiirthei' object according te the preainhie ef etairn i.

A eeeiing systern in a iieattffy *Jehieie is inany tinies ttsed te eooi a eeniiiustien engineztritt at ieztst ene tiirtiter ehjtëttt iienitttitiitig at lower etterzttirig tentpeittttitre than theeetnhttstien engine. 'the tiirthei' eiijeet tnay he the vverkiitg inethuni of a 'tätt-t R sjystetneeoiect in a, troiitieiiser, eharge air tftteted in a tfharge air ttteeier, petver eteetrenies ef aityhrid tvehieie etc. in this case, it is iieeessary te create at ieast twe differeitt etteiaittteinperatuie ieveis in the eeeting systern. Sutfh a tfeeiing systern can he eqttippedt tvitha niztins rattiztter ariti 'an auxiiiatty' rztdiatttr eeoiing the ttttohttit to a iewer' tentpetttttitrethan the inain ractiater. "the eeeiaiit ef the higher tenititeratnre is direeted te thettttnihastittn etigirie and the eeoiatnt ett* the tower ternperzttitre is ttireeted te the furthereiqieet. During eeitain eperating eentiitions stieh tfer exarnpie, ttfhen tiie eeoiiiigtieinandt efthe further ehjettt er the eeinhustien engine varies rapitiiy; it is tiitiiettit tedirect eeeiaitt at rectiiirect temperature and tientf rate te the eeitihtastioit engine as weiias te the further object in order te rnaiiitain their efficient Operating teinperatttres. inthis case, it is, for exaniivie, a risk that eoeiant etia tee iew' teirtperatttre is fiireeted te the eeniiinstieii engine.

Vit/TO 293 2/983454 shows a eeeiing system for a eornbnstion engine. The eeohiigsystetn ttoittprises a rathater in Vwhiett a, eireuiatisrig tttteizttit is eeoieti, Thte eeeiatntleaving the iadiattär is ctireetect te a housing inetadiitg two heat exehangers in vvhieii theeeeiant eeeis engine eii and transmission oii. Titus, the tfeeiant is pie-iieatett in the heat exehangers iiefere it enters the eenihnstieii engine. ti) “H5 2D SUhílt/ÉARY OF THE lNVENTIÛN The tihject otithie preseiit iiiveiitiori is to tiiftivitte a cooliiig systern ihr a ttoinhustitiiiengiiie and a further object to he cooleti to a iovver teniperattire than the eonihustionengine? att Which the coolaiit direetedt to the coinhttstion engine has a snflieient high ternperattiire during suitstaritiaily att operating contiitioris.

The above nientioneft ohject achieved hy the cotslirig systeni according to theeharacterized part of claini i. "the cooling systern creates usualiy' two coolant flott'parts iiavirtg tiitftiäifeiit teniïierzttttres, The ttoolarit tltitv part at the hi gher teirtperattuitfe isdireeted to the conihtistion engine and the coolant flow part at the lower temperature isdirected to the inrtiier ohjtettt betore it is inixtäti with the coolant tion: part at the iiigiiertemperature and directed to the cornhiistiori engine, Since the titrther ohject is to heeooied to a lova/er temperature titan the coinhttstioii engine, there is a risk that tiiecooiant flott' part leaving the titrther ohject has a si gniticantly itmfer ternperatiire thanthe tfotilant fiow part directetl to the eonihtistion engiiie. in sutfh a case, there is a, riskthat the rnixttire titsaiti ttttotztrtt tiovv tiarts Will iiave a, teniptfratitre ttootirtg theeonihtistion engine to a tower temperature than its efficient operating teinperatttre. lnorder to tëiirniiiate tiiis risk, an anxitiarjy heat :ëxttiiztriger is tottzttetl tiowrist *earth tittheiítrtliei' ohject in the auxiiiarït' eircuit. The eooiant is heated in the anxiiiarjtf heatexchanger hy cooiant leaving the coinhitstioii engine. As a, tfoiisettiieneef, the eooianttim/v part ttfhicii has cooled the thither' object Witt suhstantialiy' always have ateinperattire liigh enough to :not ttool the inixsture direeted to the tsoinhustioii engine to aternperattire cotilirig the cornhustioii engine to a lott/er temperature than its etticient operating temperature.

According to an enihotiiinent of the invention, the auxiiiarïv' eircuit coinprises anauxiiiairfy rztdiattir tiytiass Eine tiirectinig ttootztiit past the :tnxiliztryf radiator sind a bypass*valve coittigtiied to coittroi the cooiaitt illovv through the anxitiary' radiator bypass iine.in this tfase, it is possible to direct the tfoolant past the aitxiiiarjy' radiator during operating conditions When the cooiaiit has 'been eooied to a sufficieiit iovtf teinperattire ti) “H5 2D in the niain radiater te eeei the further ehjeet te an effieieiit eperating teniifferatttire.T his iiieatsuie, reduees the :risk that the tfeeiant ef a tee Eeva temperature is direeteti te the tiirthei' ehieet and te the eeinhiistieii engine, Aeeerding te an enihettiinent ef the intfentien, the engine eutiet iine eernprises aretarder eeeier. h/íaiiy' heawfšf iøfziiieies is equipped vaith a hydretijfiiainie :retardert T hetverhirig ntediuin in the retarder tusuaiiy' eeeied in a retaider eeeier hy the eeeianteiretiiating in the eeeiiiig system eeeiing ttiie eernhttstien eiigine, The auxiiiary iieatexehangei' may he arranged in an *upstreairt efthe ietarder eeeier iii the engine etttietiine. in this case, tiie eeeiaiit in the engine eutiet line is eeeied in tiie attxiiiary heattäxeitartger betere it etiters the retaifder eeettfii, As a. tteiisettitentittf, the tfeetirig itapaeity' ef the tverking niediuin in the retarder eeeier tviii iiierease. .fteeerdirtg te an enihediitierit efthe iiweiitirtn, the auxiiiatïy heat exehanger and theretarder eeeier are designed as a eehesive unit, The existeiiee etisueh unit »vitt suhstantiaiiyt net eeeupy mere space in the ivehieie than a siiigie retarder erteier, Atteerdirtg te an enihedtirtiertt 'etthe irttferttiteri, the tteeiirig systertt ttertittifises a ettntrttiunit eentigured te receive iiiferniatien aiaeut a number ef Operating parameters and tetteritiret the first tfaitfe tieviee, the setteiid 'vaive ttetfiite arid the bypass valve in tfitätv et"inferniatien aheut said eperating paraineter. The eentrei unit niay estiniate the eeeiingtieinatndt efthe tseiiihustitiii engine and the further ehjtïet hy ineans efthe Operatingparanieter and estirnate a suitahie eeeiant teinperature and eeeiant tiew rate te theeeinhtistittn engine as Well te the tiirther ehjeet at tvhitth they iiiaintain an eftieient eperating ternperatuire Atteertiirtg te an enihedtirtiertt 'ef the iiiveiitieri, ene ef saiti rtpeifatirig ttarztrtiettäifs isrelated te the teniperature ef the eeinhustieri engine. Én this ease, the centret unit niayretteivtë iriteritizttirtii írein at ternrptäifatuite serisrti' stäiising the 'tetnperatttrtë ef the eeetaiitleaving the eenittustien engine. .fftitei'natrtfeiy, a tentpeiatuie senser inay sense thetemperature efa suitable part of tiie eeinhttstien eiigiiie. One eperatiiig parameter niay he reiated te the temperature ef the further eiajeet. in this case, the eentrei unit niay ti) “H5 2D receivfe information front a temperature sensor sensing the teniiierature of the coolantleaving tthe tiirther tihiect. Alteitiiativeljø, a temperature sensor rnay sense thetemperature ofa snitahle part of the faither tihject. En oirdei' to control the ternperatiireof the coolant, it is stiitzthle to have a. terniptäiatnite serisor senlsing the teintierattitre of theeoolant entering the further object and a tenitierature sensor sensing tlie temperature ofthe coolant leaving tlie. lhrther tihiect. T he control unit iiiay oieouise ieceivfe. iiifoiniatitin tioni further iiperatiiig paranieters. .ftceordiiig to an enihotliiiieiit ofthe iiiveiition, the tirst *vfalve device is a three \Wayvalve. The three vvfajv valve niay coinprises one inlet opening and two otitlet openings.The three vva/ valve reiteiifes, vist the inlet tipeniiigt, a. coclant flow front a. line cl theCooling systern and directs a first part of it, via a first outlet opening, to the radiatorline and a second part of it, *vitt the secorid oiitlet tipeniiig, to the iadiattir bypass line.ln this case, the tirst ”vfalve device is flesignefl a single ivalve. Preferahlyz, the lirstvalve devitïc is adjiistahle in a stepless rnannei". ln tthis case., it is possible to varv thecoolant tlovv rate to the radiatoi' line and the iadiator bypass liiie With a high accnracy.iålternativfeljv, the liitst valve device is designed as two tvvo vvay valves vviliereiii a tiztsttvvo. vvauf valve i aifraiigtäil in the ratliatci” inlet. line and a. stäeoiiil tvvo v 'ay valve is arranged in the radiator bypass line. ifäceordiiig to an ernhodinient of the iiiveiitioii, the second valve device is a three vvav'valve. The three v/ay valve receivies a tfoolant llovv' lioni the radiator bypass line anddirects a pait of it to the antxiliaijv circnit and a reinaiiiiiig part ot* it to the engine inletline. lt niay also direct tsocilant front the inain radiator to tthe engine? inlet line, in thiscase, the second valve device is designed as a single valve. llieferahly, the secondvalve device is atljtistahle in a stepless nianner. in this case, it is possible to atljust thecoclant llovv rate to the atixiliaity eirittiit antl the eiigiiie inlet. line vvitli a liigli aceniacfy.Alternativelyg the second tfalve devfice is designed tWo tWo Way valves ivhereiii atiifst tvvo vvfety valve i airangiëil in a. iriaiii ratdiaftiii' tintlet line and a secoritl tivo vvay valve is arianged in the engine inlet line. ti) “H5 2D According to an enihotliinent of the invention, the first *valve device and/or the secondvfalvre device are designed to conduct small tiotilant llovv' rates ifvith a higher acenraeythan larger eoolant tlow rates. During operating eonditioiis vvhen the eriolaiit has arelatively' lovv temperature, the lirst valve tleviee ilirettts a srnall. ttoolarit tlovv' rate to thernain radiator. This small eoolaiit tlovv rate niay he iiiixed vvith a small vvarm eoolantllovtf rate. from the radiator bypass line by tlif: second valve device helore the niixture isdireeted to the tiirther olijeet. in order to ohtain a required ooolant temperature of theinixtiire *tvith a high aeeuracy., it is suitable? to use a tirst valve device and a secondvalve device With the aliove inentioiied design. 'Üïlie tiirst valve devices niay eoinprise avalve meniher movahly arranged vvit hin a nioveiiient range having an extent hetvveeii atirst erid position. in *vvhieli it tlireets no coolant tltivif to the rnain. itfadiator and a. settoriilend position in vvhich it direets the entire coolant lloW to the niain radiator. Thernoveritent r-arige tor the valve nierriher at i/vliich. it ilireets srnall itoolarit tliivifs to tlieradiator line is greater than the inovenieiit range tor the valve ineinher at vtfhieh itdireets larger coolant tlovvs to the radiator. Tlie second valve devitïe niay have a corresponding rlesign as the tirst valve device.

Atteortiirig to an enihiiiiinierit of the iriveritiori, that the liypass valve i a. two vvay' valvearrangetl in tlie auxiliary radiator 'iaypass liiie. 'Üllie flow* resistance through the auxiliarjvfrailizttor hypatss lirie is itonsitlerahly' lovver thian the .tltivv resistance throiigli theauxiliargv' radiator. 'Ül“litis, tvhen the two vvay* *valve is otieii, the main part of the eoolaiitvvill hf: direeted through the atixiliary iadiator bypass line and. a sinaller part of thecoolant through the auxiiiary' radiator. The liypass valve niay a stripdlrivif valve (eg.solenoitl valve) or a throttle valve hy ivhitili it is possible to regulate. the coolant tlovvrate through the auxiliary radiator liypass line. fälternatively, the hypass valve iriay he athree *vvay *valve arranged at a ltirariched portion hetvveen a line direeting eoolant to the ztiixiliztrjyf railiatoi* anti the aaxiliaitfy' radiator liyiiass line.

Acitortting to an. eirihotlirrient of the iriventiriri, the tiirtlier 'object is a tvorkirig rrietlinrrieooled in a condensei' in a Vvïi-llš-systeiri. ln order to aehietfe a high therinal etificiericy'in a “tltflíR-sjvsitein., the vvorlting rnediuin in the condenser is to he eooled to a eondensation temperature as low as possible and sulíistaiitialljv' vvithout suhcooiing. ti) “H5 2D Consequentijtf, in order to acliieve a high therinai ef iiciency* in a 'iVHR-systeni, theiiorkiiig inediuni is to he cooled ivith a suitahle cooling ettetft. Houffzver, the suitahlecooiing ettect ofthe working niediuin in the coiideiisei' cvaries tiuring differentriiieratiiig conditions such tvitii the iiezit effect supplied tfrorn, for exainiiile, theexhaust gases to the evaporator. Since the supplied heat from exhaust gases can *varyrapidlja, it is difficult to tfontiniiousljif provide a cooiirig etiect of the vvorkiiig incdinniin the condensei' resulting in a liigli thernial efficiency' ofa Vtïi-iR-syistein. [accordingto tiie iiiveiitioiíi, cthe first valve tietficefi tiie second valve device: and the bypass Valveare controlled in a niannei' such that Workiiig inefiiiirn is condensed in the coiideiiser ata desired condensatioii teniiierature. Alternatitfelyg the further object charge airttooied in a ttharge air itooier oi' another' rihjettt dernaniiirig cooiing to a, lower temperature than the coinhustioii engiiie. .ffiociördirig to an enihotiiiiierit ofthe iiiveiition, the auxiiiary radiator is arranged in aposition in the xfehittie in iviiieh it is tfooled hy an air stream of a lov/ei" teinptfieiturethan the temperature ofthe air streain tiiroiigh the niain radiator. The niain iadiator usually arranged hehind a charge air tsooler or another ifooler att a iiront portion tifatieiiicle. Thus, the air stifeziins tiirriiighi the niairi iadizttor iisuztiiyf has a liigiierteniperattire than the surrounding air teinperatiire. "fire auxiliary* may he providedheiovv, above or at one sifie tittlrie inaiii radiator tviiere it is cooieri 'ray an air stream of stirrouiidiiig air tenitierature. .ffiociördirig to an enihotiiiiierit ofthe iiiveiitirin, the air streain tiiroiigli the auxiiiarjy' rad iator is geiíierateti hy a separate ratliator fan. Such an anxiiiary' radiator tan inay Leirideperideritiy controlled in reiation to a inain radiator fan torciiig air through the inainradiator. The auxiliarjyf radiator fan inay he driven 'hy an eiectric niotor. in this case, itis possihie to control the tfooiirig etteot 'ofthe ttooiarit in the ziiixisiiztry railiatrii” in rirtlei'to cool the further oliject to an efficient operating temperature. in order to reduce theeonsiiniptiiin rifehfctriit eriergy, the :iuxiiiriryf radiator is arifaiigfifri in a positiori iiftiievehicle vviieie it receives a cooling air streani hy the rani air and the auxiliarjy' iadiator fan. ii) “H5 2D BRIEF DESCRllYFltÜNi GF DRiåWlNífíS in the tbiltötmirig a preteirreti enihtadinierit ofthe iriveritioii is tleserilied, as an exanipie,With reteieiice to the ztttaciieii tlrattvinsgs, in vviiieii: Pig. l shovvs a cooling systern according to an einhcitiiinent of the inventitin aiitlPig. 2 shows a tront view otthe rnain radiator and the aiixiiiary' radiator.Diíšflfiltilçiíšli) Diiššífišfli EYPEÛN íši* A iiišišiiïiilšiåiši) tšhftíštflši}itvítlšll~l'fi“ GF 'Ti-iiilNltfENïïtšN Pig. l shows a seheinaticalljtf disclo sed vehicle l powered hy a coinhustioii engine Tile tfeiiicie l niay be a hfeatfy' *tfeliiele and the ttoniliustitin engirie 2 iiiay be a, dieselengine. The vehicle l cornprises a Cooling stfsteiii eoniiiiisiiig an eiigine iniet line 3providedt wi/itth a ptinip 4 cireulattiiig a tsooiant in the cooliiig systeni. The coolant isinitialiy cireiilated tiiroiigh the eoniliustion erigiiie 2. 'lite eoolant leaving thecoinbnstioii engine 21 is receive-ti in an engine tintiet liiie 5. A lirst 'tfalve device in theforin ofa first tiiree »tf-any valve 6 is arrangetl at an end of the engine tnitiet line S, Thefirst three ttfay valve 6 has one iniet opening and two ontlet openings. The coeiingsysteni ttoiiipristäs a niairi ratliattii* liite 7 tlireeting coolatnt through a iiiztin ifadizttor 8,The niain ratiiator line 7 coinprises a niain racliator inlet line Ya, and a rnain racliatortititlet liiie 7h. The tttioling sjystein ttoniprises a inaiii radiator bypass line 9 tlirectiiigetioiaiit past the niain rarliator The tirst three Way valve (i is controlled hy a controlunit lÛ. The lirst three Way valve 5 is attiustahie in a, stepless iiianner, Thusg it istirissilile for the tirst three ttvay ”tfaive ti to receive etiolaiit trorn the engine ontlet iine 5vitt the iniet opening and tiistrilitite a first part of it to the racliator line 7 tfia a tirsttiutlet otietiinsg aint a. settontl ieiiiztiniiig part of it. to the rztfiiattii' hytiatss line 9 *Jia asecond outlet opening. A charge air cooler ll is arrangeti in a position tipstreani of theniairi iatiizttor 8, A radiator tant lZ znicl the ram ztii' pitfovititf ai cooiing air streani through the eliarge air eooiei' lZI anti the niain radiator 8 diiriiig operation otithe tvehieie l. ti) “H5 2D The eooiing systern eontignred to eoo1 at ieast one further ohjeet 13 than theeonihnstion eiigine 2i Tiie tiirther rihjeet 13 is airraiigect in an aiixitiary* tsireiiit 14 of theeooiing systern. 'the thrtiiei' object 13 is in this case exeinpiitieci as a stvorking niertininin a “thfiiR systerri i/tfiiieh is ttooieri in a eonoeiiser 13, ,A1tei'riatiive1y, the tiirttier tihjeetrnay he charge air eoo1ei' in a eharge air eooier, power eieetronies for a hyhriti vehie1eor anrither objeet to he tfooied to a lov/ei" teniprzrrature than the eonihtistion tärigine. Theauxiiiairy eireuit 14 eonipiises an auxiiiarys iadiator 15 airanged iipstrearii of theeoiitiensei" 13 in view of tiie tiovu direction through the aiixiiiary* tsireiiit 14. Tiie rain airanti at Eeast one ansxiiiary ratiiator tån 15 provides a eooiing air stream through theatixiiiary ractiator 15. An auxihary* ractiator tijyïnass 1ine 17 tiireeting eooiaint past theauxiiiairy ratdiatrir 15, A bypass valve 18 itontrtiis the ttoohtrit tiotv throtighi the bypass 1ine 17. The bypaiss Vaive 18 eontroiiect by the eontroi unit 111.

A second vahve device in the torrn of a second three iifay sva1ve 2G ieeeives eooiantironi the ratiiator bypass 1ine 9. The second ti "ee »way Valve 2G is eontroihztt by theeontroi unit 11). The second three »ri/say *uaive 211 adjnstahie in a stepiess rnaiiiiei: 'Thesetsoiiti three Way 21) xfah/e has an in1et ciprziiing retteixfing tfooiant ironi the iiiainratdiaittii' tiyiiztss 1ine 92, an o utiet ripenirig direeting tttioiztrit to the erigiirie irii et iiiitf få ainta third opening *which inay he an in1et opening or an outiet opening. The third openingniay i/vorft: as sin iiiiet opening ainti receives ttoo1arit iifoni the iriaiii rariiator 8 ziriii di “eetit to the engine in1et 1ine 3. Aiternatitfeiy, the third opening 'aforks an otitiet openingand cineets eooiant froin sthe niain ratiiatrii* bypass 1ine 9 to the atixiiiary eireuit 14-. Atirst teinperatuire sensor 21 senses the temperature ofthe oooiant in the engine outiet1ine ii, Thus, the tirst ternperatuire sensor 21 seiises a teniperatiire related to thetemperature of the eonihustion engine 2. A second ternperatiire sensor 2221 senses thetemperature of the eooiant in the anxiiiarjyf eireuit 14 in an upstreain position of theeonríeriser 13, A tiiirri teniperattiire sensor 2213 seristfs the terriperaituitfe of the eootaiit inthe anxiiiarfy eireuit 14 in a dovtfnstreani position of the eontienser 13. The thirdteiriperattirtä stfnsor 2213 senfses a. terniptëiatniftf reiattëit to the teiriperzttiire rita* the wvorkinigiiiediiiin in the etandenser 13. 'The auxiiiairy Circuit eonipirises an auXiÉiary heatexehanger 23 arranged donfiistreain ofthe :tendenser 13, The eooiant in the auxihary' eireuit is heatect in the auxiiiary' heat exehanger 23 hy eooiant in the engine ontiet Eine ti) “H5 2D 5. A retartier ceeier 24 is arraiiged in the engine eutiet iine 5 in a dewnstreani pesitieneftiie atixiiiary heat exehanger 23, in this ernhectirnent, tiie arnxiiiary heat exeiianger 23aint the retarder ceeiei' 24 are tive separate uiiits, Aiteiriiativeiyg the auxiiiaryc heat exchtaneger 23 ztriti tiie retartier etiettfi* 24 rnayf he tiesignteti as a ttehesisftf iinit, Duriiig eperatieii, tiie centret unit ti) ireceives snhstantiaiiy' eentiniieusiy interinaitiriiitieni said ternperature seiistars 21,, IZZa, 22h aiieut the aetiiai eeeiant ternperatures ettheeeinhustieii engiiie 2. and the wverrhing rnediuin in the tseiitteiiser 13, The centret unit 1Gmay aise receive irtferniatien aheut töperatirtg parameters ef the Vtfiiiš system, 'Thecentret unit it) inay, ter exaniriie, receive iiiferniatien aheut the aetuai eendensatienteiriperattiire in the tteiirieiiser 13, Thie centret unit it) estiiriattfs a iiesiireti eentíerisatieritemperature ef the iiferhiiig inetiiuiii in the centieiiser 13. Wiieii ethaiiei is used asVwerhintg riietiiiirn, a ceiideiisartieri teinperzttiire titiabeiit íštWtfI is tiesirabitf duririg rnesteperatirig centiitieiis. 'The centret unit ti) estintates a require-Il tiectw' rate artti a requiredteinperatiire ef the ceeiant tievu te hr: direeted te the eenctensrfi* 13 in rirdter te previde the tiesired centieiisatitin teinperatitre in the eentleiiser 13.

Diiring ripeitfatient, the centret unit iii ireceives suhstztntiaißf tteritiriiitiusiy' irifernizttierifrein the first temperature senser 21 aheut the eeeiant temperature in the engine eutietline S, in ttase the eeeiaiit ternperzttiire in tiie engine e utiet Eine 5 iririieattes that tiieceinhustien engine has a ieWei' teniperattire than an efficient eperating temperature,the tfenihustiriii engine 2 dees net need te he ttrieiect. Tiie centret unit it) aidjiists thetiirst three »ifay vaive 6 sitch that it tiirects a iarge part ef the ceeiant iiew te the ratiiaterbypass iine S3* and a remaining sinaii part ef the ceeiant tievu te the ratiiater hne 7. Theseeentl vatve device 2G tiireets the eeeiant tieni the iitaiii radiater iiypass tine 9 te theceinhustien engine 2 Without eeeting. The sinaiier part ef the eeeiaiit tiieW is usuaiiyeeeieri in the rneain ratiiattii' 8 te ternperzttiire iew erieugh te ceet the tverkirig niectiiiiriin the cendenser i3 te a stiitahie cendensatien temperature. in this ease, it is netnecessary* te use tiie asuxitiary iratiiztter 15. Titus, tiie centret unit ti? sets the iaytiassvatve itä in aii eriert pesitien sueh that the ersetaitt is directed iiieitt the main rathater' 3te tiie cendenser ifš Via tiie arnxiiiary' rattiater bypass iine. 17. in tiie ceeiaiit has heen ceeieti te a tee ieW temperature in the niain ratiiater S, the seeeiict three tvay ti) “H5 2D 1G valve 20 is eentreileti stieh that it clireets a suitable quantity efuneeelecl eeelecl freinthe rnaizn radiatei" bypass line 9 te ithe auxiliary tïireitit 14 vvlifzie it is iiiixetl wvitheeeiant fieni the iii-air: racliater 8. *vlvïith a suitahte niixture tifsaid eeelants et" differenttenipeiitttittes it is ipessilile te direct etietaiit etfa suitzthle ttëiiiïierzttitre te the eetitlerise l 3, via the auxiliary ratiiater litjfpass line 17, at ivhieh the iverking niecliurn is eeeied inthe eenclenser lš te the desired eentiensatien teniiaerature.. The trtielant leaviiig theeeiideiiser 13 enters the aiixiliarjy' lieat exehangers 223 Where it is heatetl ivitli eeelant inthe eingine eutlet line 5. Thus, the tfetilant tiireetfztl frein tlie atixiliary* tfireti it te tlieengine inlet line 3 and the eernhustieii engine IZ *vi/ill during suhstaiitiatitf all riperatiiigeenditieiis liavfe a stiffieient high temperature ter rising the tenitierature ef the tttiniliustitiii erigirte 2 tapitily te its efiieieiit 'eperatirig ternperzttiire, ih case the etielant terniptäiatuiie in the eriginfe e utlet line 5 iiittieztttës tiiat the tttiniliustitinengine IZ has a temperature vtfitliiri an eftieient tiperatiiig ternperatitre range, theeenihtistien engine 2 ineed te he tfeeled in ertler te inatiiitain this teniperatitre, Theeeiitrei unit lt) afljiusts the tiist three vvay valve (i such that it tiireets a suitable part efthe tfeelant llew te the ratiiatei" hygiass line 9 and a remaining part ef the eeelant tlevvte the rattlittter line 7, The seeehti valve tleifittfif 2G tiireets a suitable inixtiire tilieeelratntfrem the niain ratiiater bypass line 9 and eeelant ferin the inain racliater 8 te thetttiniliustitin engirie 2, On ene hainlt, the eeeiaiit thiw in the nittin iatiiztter 8 is eeeietl tea teinperature leW eneugli te eeei the vvferltiiig rnetiiuni in the eenclenser l3 te astiitahle eenclensatien teinperattire. ln this it is net necessary te use the auxiliarjaradiater lfš. 'l'ltus, the centret unit lt) sets the bypass ”xfalve lä in ah epen tnisitien suelithat the eeelaiit is tiireeteti freni the inain radiatei" 8 te the tsentleiisei" 13 via theauxiliairy radiater liypass Eine l7. Ûn the ether hanft, the eeelant tlew in the niainracliater 8 is net eeeleti te a tenitierature levv' eneugh te eeei the iverking niecliuin inthe etnittfifiistëi' l3 te a suitable tteiicleiisatitiii tenipfifiitttitre. ln this case, it rieeessztrjy] teuse the atixiliary' racliater 15. Thus, the centret unit lt) sets the bypass valve lS in attleseti pesitieri such that the eeelaiit is tiieettëti tiïiih the tnaiii rzttliattii' 8 te theeeiideiiser 13 *via the auxiliary radiater li, in case the eeelaiit leaving the eendenser l3Ihas a, relatively' lew temperature, it is lieatett in the auxiliary lieat exehanger 23 hefcirf: it enters the eenihustieii engine 2. The existenee ef the auxiliary heat exehanger 23 ti) “H5 2D 11 guarantees that the eeo1ant entering the eeinhustieii engine has a tenitierature liighene u gh te inaintain the teinperatttre ef the eemhtistien tängiiie 2 tvitiiiii an efficient eperating temperature range. 1n case the eeo1aiit tenigterature in the engine out1et 1ine 5 indieates that the eeinhustieiiengine. 2 iias a higher temperature than an efficient Operating teiiíiperattire range, theeernhtustieii engine 2 need te he eee1et1 in att epitirnai nianner. The centret unit 11)adjusts the tirst three *way *valve 6 sueh that it dizreeta the entire tfnelant tlew te theradiater line 7 and the inain radiator 8, 'Üi1ie seeend vatve fteviee 211 direeta a suitahiepart ef eneiaiit frem the niain radiator to the eernhttstien engine 2. A reinaiiiiiig parttitithe ttnnhtrit tievv is direeted to the anxihairy' eirtttiit 14. in ttase the tfeelztrit tiew in theinain radiater 8 has heen eoeied te a temperature ievtf eneugh te eee1 the iverkinginettitini in the ttrinthënser 13 te a, suitzthitf etirtftertsatitirt ternperatuire, the ttentre1 uiiit lt)sets the bypass vatve ltš in an orten pesitieii auch that the etiniarit is direeted horn themain rattiatei* 8 te the eendenser 13 via the aiixiliary' radiator hypatss liite 17. 1n trasethe eeniarit thiw in the main radiater 8 ia inet eeetetl te a temperature inte eiieugh teeeei the ttferkiiig inediuni in the tfuiitteiiser 13 te a suitable eendensatien temperature.,the erintrrit tinit 10 sets tiie bypass 'tfztlve 18 in a ttlnstëri tiesitieii auch that the erietatnt isdireeted frem the niain radiatnr 8 te the eendenser 13 via the atixiiiary radiater 15.tfïeriseqneiithf, the eeeting syiaterni is abte to rh-aintairi an effieierit tiperatirtg teiniperattirtëef a eenihustieii engine 2 »vett as a desired eendensatien ternperature ef the tiforhing inedium in tlie eendenser 13 tiuriiig stihstantiaihf a11 eperating eeiíitlitiens.

Pig. 2 s1íiriwvs at iient Vietv etithe main radiater S and the aiixihary rattiatei* 15. In thiscase, the auxihary radiater 15 ia airaiiged heievif' the rnaiii radiater '1“tw'ti auxiliaryradiater fans ltš provides a eeeting air streani through the auxihary radiater 15. 'Üïheztiixiiiztrjyf rarhatei” tans 16 nitty he driven iiidtätttfiiritfiitty e ti the niain iadiztter tatt 12.Alternatitfeljø, the atixiiiarftf radiator 15 niay the arranged atíteve or en a side ef the niainratiiztter 11, Pretierabty, the auxihztry rattiatrii* 15 is arrztrigett in a iteaititini siteh thatireeeives a etiehrig air stream hy the rain air aiid the auxitiary fan rattiater tana 16 at thesurrounding teiiiperattire, in this ease, it is possible te tfeei the eee1aiit te eensiderabh/ lett/er teinperature than in the main radiator 12 The ínweníiøn is :not rfzsfiçríctcö: to the described ernbodirncni, but 1112:31 be *aaried ficeiy' vvitíïii: :ha scøgre sf the ciainïs.

Claims (15)

Claims

1. A cooling system configured to cool a combustion engine (2) and at least one furtherobject (13) in a vehicle (1), Wherein the cooling system comprises a radiator line (7)directing coolant through a main radiator (8), a main radiator bypass line (9) directingcoolant past the main radiator (8), a first valve device (6) receiving coolant from anengine outlet line (5) and directing it to the main radiator line (7) and the main radiatorbypass line (9), an auxiliary circuit (14) directing coolant to the further object (13), anengine inlet line (3) directing coolant to the combustion engine (2), a main radiatoroutlet line (7b) directing at least a part of the coolant leaving the main radiator (8) tothe auxiliary circuit (14), and a second valve device (20) receiving coolant from themain radiator (12) and/or the main radiator bypass line (9) and directing it to theauxiliary circuit (14) and/or the engine inlet line (3), characterized in that the auxiliarycircuit (14) comprises an auxiliary radiator (15) in Which the coolant during mostoperating conditions is cooled to a lower temperature than in the main radiator (8), andan auxiliary heat exchanger (23) located doWnstream of the auxiliary radiator (15) inthe auxiliary circuit (14), Wherein the coolant is heated in the auxiliary heat exchanger(23) by coolant in the engine outlet line (5) before the heated coolant is directed to the engine inlet line (3).

2. A cooling system according to claim 1, characterized in that the auxiliary circuit(14) comprises an auxiliary radiator bypass line (17) directing coolant past theauxiliary radiator (15) and a bypass valve (18) configured to control the coolant flow through the auxiliary radiator bypass line (17).

3. A cooling system according to claim 1 or 2, characterized in that engine outlet line (5) comprises a retarder cooler (24).

4. A cooling system according to claim 3, characterized in that the auxiliary heatexchanger (23) is arranged in an upstream position of the retarder cooler (24) in the engine outlet line (5).

5. A Cooling system according to claim 3, characterized in that the auxiliary heat exchanger (23) and the retarder cooler (24) are designed as a cohesive unit.

6. A cooling system according to any one of the preceding claims, characterized in thatit comprises a control unit (10) configured to receive inforrnation about at least oneoperating parameter (21, 22a, 22b) and to control the first valve device (6), the secondvalve device (20) and the bypass valve (17) in view of inforrnation about said operating parameter (21, 22a, 22b).

7. A cooling system according to claim 6, characterized in that one operating parameter is related to the temperature of the combustion engine (2).

8. A cooling system according to claim 6, characterized in that one operating parameter is related to the temperature of the further object.

9. A cooling system according to any one of the preceding claims, characterized in that the first valve device is a three Way valve (6).

10. A cooling system according to any one of the preceding claims, characterized in that the second valve device is a three Way valve (24).

11. 1 1. A cooling system according to any one of the preceding claims, characterized inthat the first valve device (6) and/or the second valve device (20) are designed to conduct small coolant floW rates With a higher accuracy than larger coolant floW rates.

12. A cooling system according to any one of the preceding claims 2 to 11,characterized in that the bypass valve (18) is a tWo Way valve arranged in the auxiliary radiator bypass line (17).

13. A cooling system according to any one of the preceding claims, characterized inthat the further object is a Working medium cooled in a condenser (13) in a WHR- system.

14. A Cooling system according to any one of the preceding c1aims, characterized inthat the auxiliary radiator (15) is arranged in a position in the Vehic1e (1) in Which it is coo1ed by an air stream of a 1oWer temperature than the temperature of the air stream through the main radiator (8).

15. A coo1ing system according to any one of the preceding claims, characterized inthat the air stream through the auxiliary radiator (15) is generated by a separate radiator fan (16).