The energetic balance of the friction clutches used in automotive

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1 Recen Reseches in Auoic Conol The enegeic blnce of he ficion cluches use in uooive BOROZAN ION SILVIU, MANIU INOCENTIU, ARGESANU VERONICA, KULCSAR RAUL MIKLOS Mechonics Depen Poliehnic Univesiy fo Tiiso, Mihi Viezu Blv., RO-300, Tiiso ROMANIA Absc: - The enegeic nsfe hough he ficion cluch is ccopnie by issipive pocesses. The cuses h pouce hese pocesses e he ficion fo he ple pckge. The issipive esicions h e inepenen of he epeue gien o he iecion of he he flux pesen in he cluch s ss e ipose by he xiu epeues ie by he ficion eils, by he eleciclly insuling eils n he lubicn (if i kes plce in we envionen). Key-os: - cluch, ficion, enegy, lo, issipive, heing Inoucion A cluch is evice which nsfes enegy fo one oing shf o nohe in oe o pefo soe useful wok. In he siples es, cluch cn be hough of s sing evice becuse h is wh hppens when cluch is engge. Bu, oe iponly, while engge i is nsfeing enegy. The cluch kes enegy fo powe souce such s n engine n nsfes i o whee i is equie. A cluch consiss on wo hlves: iving hlf n iven hlf. The iving hlf is che o he powe souce n oes wih i. The iven hlf is che o he shf equiing he enegy n is se wih ech enggeen. In iion, he cluch us hve soe ens of engging n isengging he wo hlves. Ficion couples ely upon ficionl foce occuing beween wo sufces o evelop he equie oque. The oque is clle ynic oque when slippge occus beween he sufces n sic oque when no slippge occus. Usully he wo sufces e of issiil eils. The cobinion of he wo eils use is efee o s ficion couple n hei concing sufces s inefces [7]. hen he ficion couples opees wihin flui, i is efee o s we opeion. Dy opeion oes no epen upon he pesence of flui. Also wihin he we cluch oil iives, especilly he exee pessue/ni-we iive hs beneficil effecs on he ficionl chceisics n he we of he ficion eil [3]. The oque nsie is ele o he cuing foce, he coefficien of ficion, n he geoey of he cluch o bke. This is poble in sics which will hve o be suie sepely fo ech geoeic configuion. Howeve, epeue ise is ele o enegy loss n cn be suie wihou eg o he ype of bke o cluch, becuse he geoey of inees is h of he he-issiping sufces [4]. The cenifugl cluch is use osly fo uoic opeion. If no sping is use, he oque nsie is popoionl o he sque of spee. This is picully useful fo elecic-oo ives whee, uing sing, he iven chine coes up o spee wihou shock. Spings cn lso be use ISBN:

2 Recen Reseches in Auoic Conol o peven enggeen unil cein oo spee hs been eche, bu soe shock y occu. Mgneic cluches e picully useful fo uoic n eoe-conol syses. Such cluches e lso useful in ives subjec o coplex lo cycles. Hyulic n pneuic cluches e lso useful in ives hving coplex loing cycles n in uoic chiney, o in obos. Hee he flui flow cn be conolle eoely using solenoi vlves. These cluches e lso vilble s isk, cone, n uliple-ple cluches [4]. The hel pocess cuse by he elive slip of he ficion sufces (in iec conc o by he use of he lubicn) is he os inense n eningful pocess. I s iponce in he enegeic blnce of engging n isengging cn be shown hough siple ifice pplie o he oion equions. Enegy consieions hen he oing ebes of chine e cuse o sop by ens of bke, he kineic enegy of oion us be bsobe by he bke. This enegy ppes in he bke in he fo of he he. In he se wy, when he ebes of chine which e iniilly es e bough up o spee, slipping us occu in he cluch unil he iven ebes hve he se spee s he ive. Kineic enegy is bsobe uing slippge of eihe cluch o bke, n his enegy ppes s he. e hve seen he oque cpciy of cluch o bke epens upon he coefficien of ficion of he eil n upon sfe nol pessue. Howeve, he chce of he lo y be such h, if his oque vlue is peie, he cluch o bke y be esoye by is own genee he. The cpciy of cluch is heefoe liie by wo fcos, he chceisics of he eil n he biliy of he cluch o issipe he. In his secion we shll consie he oun of he genee by cluching o bking opeion. If he he is genee fse hn i is issipe, we hve epeue-ise poble. In he following wing you cn ge cle picue of wh hppens uing siple cluching o bking opeion, which is heicl oel of wo-inei syse connece by cluch. As shown, ineis n hve iniil ngul velociies of n, especively. Duing he cluch opeion boh ngul velociies chnge n evenully becoe equl. e ssue h he wo shfs e igi n h he cluch oque is consn. Fig.. Dynic epesenion of cluch. iing he equion of oion fo inei gives: () hee is he ngul cceleion of n T is he cluch oque. A siil equion fo is: () e cn eeine he insnneous ngul velociies n of n fe ny peio of ie hs elpse by ineging equions () n (). The esuls e: (3) (4) The iffeence in he velociies, soeies clle elive velociy, is: (5) The cluching opeion is coplee he insn in which he wo ngul velociies n becoe equl. Le he ie equie fo he enie opeion be. Then 0 when n so equion (5) gives he ie: (6) This equion shows h he ie equie fo he enggeen opeion is iecly popoionl o he velociy iffeence n invesely popoionl o he oque. e hve ssue he cluch oque o be consn. Theefoe, using equion (5), we fin he e of ISBN:

3 Recen Reseches in Auoic Conol enegy-issipion uing he cluching opeion o be: (7) This equion shows h he enegy-issipion e is gee s, when 0. The ol enegy issipe uing he cluching opeion is obine by ineging equion (7) fo 0 o. The esul is foun o be: (8) Noe h he enegy issipe is popoionl o he velociy iffeence sque n is inepenen of he cluch oque. Noe h in equion (8) is he enegy los o issipe. 3 Poble foulion The oion equions cn be wien in he iffeenil fo: ( M M ) ω ( M + M M ( ω ω ) C ) ω + (9) O in he inegl fo : u + + (0) hee: ω, M, J, (of cceleion) ;,ynic ficion cluch J ω hen engging wih lo, he os coon cse foun, hee e wo phses: ) ; Mc( ) M ω ( ) ω ω0 hen he enie enegy ken ove by he cluch is nsfoe ino he heic enegy n islocion enegy (usge enegy): M C () b) ; MC > M ω ( ) < ω ω > 0 h coespon o he cceleion of he secony shf, when fo he ol enegy ken ove by he shf wih he sepion of he effecs, you cn isinguish he coponens fo : -Defeing he exeio esisnces (M₂) u M ω (3) -The cceleion of he euce sses he secony shf ω M ω J (4) -Dissipive pocesses cuse by ficion M + M 0 (5) ı - he ol enegy ; u he useful enegy; he enegy neee o ccelee he euce sses he secony shf ; issipe enegy hough ficion. The evluion of he issipion pecenge when engging on boh ses loe n unloe is ccoplishe by he iensionless loss coefficien: α ; α 0 () u This elion poves h he less fvoble siuion une he enegeic blnce spec belong o he no lo sus (wih soe siplifie hypohesis [,, 5 n 6] fo ω₁,₂ () n M C () α o 0.5, becuse Fig.. Enegy blnce ISBN:

( ) MC M C x exp τ o (7) Becuse of he piculiies in he pocess of engge n isengge, you will lwys hve : >( ) If funcioning fo long peio of ie in he isengge sus, hee cn ppe n ipon ple pckge heing, ue o

4 Recen Reseches in Auoic Conol Fo he whole loe engge pocess, he issipive enegy hs vlue (fig..): + ) MC + M ( + + M ω α M 0 x ( τ, S) exp 0 β K η τ ω (6) Deling in siil wy, i cn be eeine he expession fo he issipe enegy isengge sus. ( ) MC M C x exp τ o (7) Becuse of he piculiies in he pocess of engge n isengge, you will lwys hve : >( ) If funcioning fo long peio of ie in he isengge sus, hee cn ppe n ipon ple pckge heing, ue o he eining oque. The issipe enegy fo his e cn be expesse in quniy wih he expession: ( ) 0 M ( ω ) ω ( ) 0 0 M ω (8) fo engge o isengge ses, in polonge peio of ie, he oun of he evelope cn be highe hn he one pouce in cceleion n bking. Thus, his funcioning egie us be ccoe specil enion, becuse ignoing i coul le o jo eficiencies. Fo he quniy eeinion of he issipive pocesses you us know: he engging kineics ( ω ),so ω () ), he ibologicl n,( elecogneic behvio of he cluch M C (),M C () n M ( ω ). Becuse he possibiliies fo hel chging epen o he cooling coniions, when veifying he he clculus you us consie he wok egie of he cluch. Thus in h coupling coniions he ol issipe enegy single use us be cope o he ie enegy fo issiping hough his inequliy: ) ( (9) In he esy n oee coupling coniions, he xiu issipe enegy in one hou will be cope wih he ie vlue : h Z ( h ) (0) ( ) oh ( h ) () hee: Z e of civions pe hou. The e of civions pe hou cn be seen in Fig. 3 whee i is shown is epenence on he ix lo wok of ficion (in loe n unloe ses) n he cluch iension. The viion of he esueens h eeine he enegeic blnce in possible n funcionl egies e shown in figue. The hche sufces show he issipe enegy when ω > 0. Fo he nlysis of he ls hee equions (6),(7) n (8), i cn be seen h he heing of he cluch is inense he longe slip egie. In he cse of wong iensioning, he ficion sufces cn ge won peuely n even be esoye hough oveheing. If he fequency of he swiching beween egies is oe ofen, he coniions becoe he. 4 Poble Soluion Alhough he issipive phenoenon cuse by he eining oque is less inense hn he one Mix lo wok of ficion [J] Re of civions pe hou Cluch iension Fig. 3. Re of civions pe hou. ISBN:

5 Recen Reseches in Auoic Conol lge nube of cluches n bkes in hei buil, o h hve he cooling coniions ifficul, us no be neglece. Fig. 4. The effec of cluching opeions on epeue. Figue 4 shows he effec of cluching opeions on epeue. is he bien epeue. Noe h he epeue ise y be iffeen fo ech opeion. A ie cluching o bking opeion cuses he epeue o ise o A. Though he ise occus in finie ie inevl, i is ssue o occu insnneously. The epeue hen ops long he ecy line ABC unless ineupe by nohe cluching opeion. If secon opeion occus ie, he epeue will ise long he she line o n hen begin n exponenil op s befoe. 5 Conclusion Depening upon pplicion, i y be esible o hve lge o sll iffeenil beween he sic n he ynic oques. Fo insnce, when enggeen is e es(no slippge beween inefces), s woul occu fo cluch-coupling o holing bke, he sic oque shoul be oe oinn. If he cluch o bke is equie o slip coninuously, s in ensioning pplicion, vey lile iffeenil is esible o voi sick-slip coniion. The expeienl pog hs vil iponce becuse of he big influence of he cooling wy of he cluch n he envionenl flui use fo his pupose. The esuls evel soe phenoenologicl piculiies, offeing hus useful fo he pcicl pplicions. Even slle quniies pouce in echnicl nsissions h hve 6 Acknowlegen This wok ws pilly suppoe by he segic gn POSDRU/88/.5/S/50783, Pojec ID50783 (009), co-finnce by he Euopen Socil Fun Invesing in People, wihin he Secol Opeionl Poge Hun Resouces Developen This wok ws pilly suppoe by he segic gn POSDRU 07/.5/S/7765, insie POSDRU Roni co-finnce by he Euopen Socil Fun Invesing in People. This wok ws pilly suppoe by he segic gn POSDRU//.5/G/3798, insie POSDRU Roni , co-finnce by he Euopen Socil Fun Invesing in People. Refeences: [] Bekov Yu. P., Nuov E. D., Peov V. V. n Shny S. V., Dignosic eho n evice fo ficion couples, Cheicl n peoleu engineeing, Vol. 9, No., 993, pp [] Nunney, M. J., Ligh n hevy vehicle echnology, Elsevie L., 4 h eiion, 007. [3] Sco., Suniwn P., Effec of oil iives on he pefonce of we ficion cluch eil, 0h Inenionl Confeence on e of Meils, Volues 8-83, P, Mch 995, Pges [4] Shigley, J., Mischke, C., R. Buyns Mechnicl Engineeing Design, 7 h eiion, McGw-Hill Science/Engineeing/Mh; 7 eiion,july 5, 003, ISBN: [5] Vnoe P., Depez P., Plce A., Gillo D., Ficion suy of cbon-silicon cbie couples, Poceeings of he Insiuion of Mechnicl Enginees, Jounl of Engineeing Tibology, Vol.4, No.5, 000, pp [6] ils E. V., Cohen H., The oion of wo xi-syeic igi boies wih ficion coupling, Zeischif fü Angewne Mheik un Physik (ZAMP), Vol.53, No., 00, pp [7] Clog no. 800, Eon Copoion, Aiflex Cluches n Bkes, 997, Cleveln, Ohio ISBN:

ANALYSIS OF KINEMATICS AND KINETOSTATICS OF FOUR-BAR LINKAGE MECHANISM BASED ON GIVEN PROGRAM

ANALYSIS OF KINEMATICS AND KINETOSTATICS OF FOUR-BAR LINKAGE MECHANISM BASED ON GIVEN PROGRAM SINTII POINGS IV INTNTIONL ONGSS "MINS. TNOLОGIS. MTILS." 7 - SUMM SSSION NLSIS O KINMTIS N KINTOSTTIS O OU- LINKG MNISM S ON GIVN POGM W ISSN - PINT ISSN - Pof.soc.. Shl Pof.soc.. Likj. * Pof.ss.. ji.