 has been proposed (Japanese Patent No. 3084692) which comprises a rotatable fuser roller having an outer surface coated with an elastic member and a built-in heat source, a heat-resistant belt which is tensioned by a plurality of supporting rollers, and pressurizing means which brings the heat-resistant belt to be wrapped around the fuser roller partially for a predetermined angle to have a nip area and applies pressure locally such that the pressure on an outlet of the nip area is larger than the pressure on the other portion to create a deflection in the elastic member for facilitating the ejection of a sheet medium from the nip portion.
In this conventional fixing device, the fuser roller has a deflection beforehand in the surface thereof because of the existence of the pressurizing means. At the outlet of the nip area, the deflection is instantaneously cancelled from a state that toner is in contact with the surface of the fuser roller. Therefore, when ejecting the sheet medium from the nip portion, the adherence between the toner and the fuser roller is reduced to prevent the sheet medium from adhering to the fuser roller, whereby even a weak recording medium can be easily peeled off at the outlet of the belt nip portion. Therefore, this device achieves the elimination of a peeling pawl which has been used in a prior technique.
Further, a fixing device has been proposed (Japanese Patent Publication No. H06-40235) in which rollers have a preset pressure therebetween to deform the roller(s) to form a nip and a sheet medium having an unfixed toner image thereon passes the nip, thereby fixing the toner image. Depending on the characteristics of the sheet medium, the driving speed of the rollers can be selected from a first speed and a second speed.
Furthermore, a fixing device has been proposed (Japanese Patent Unexamined Publication No. H08-262903) comprising an endless belt which is tensioned in such a manner as to travel while being in contact with a rotating fuser roller which has an outer surface coated with an elastic member and a built-in heat source and a pressure pad which is non-rotatably arranged inside of the endless belt to press the endless belt to the fuser roller to form a nip and to deform the elastic member as the outer layer of the fuser roller, wherein a sheet medium having an unfixed toner image thereon passes between the fuser roller and the endless belt, thereby fixing the toner on the sheet
has been proposed (Japanese Patent No. 3084692) which comprises a rotatable fuser roller having an out open coated with an elastic member and a built - in estrus source, a heat - repellent swath which is tensioned by a plurality of supporting rollers, and pressurizing means which bring the heat - resistant belt to be wrapped around the fuser roller partially for a predetermined slant to have a nip area and apply pressure locally such that the pressure on an mercantile establishment of the nip sphere is larger than the imperativeness on the other portion to create a diversion in the elastic member for facilitating the ejection of a sheet medium from the nip portion. 
 In this conventional fixing device, the fuser roller has a deflection beforehand in the surface thereof because of the existence of the pressurizing means. At the mercantile establishment of the nip area, the diversion is instantaneously cancel from a department of state that toner is in contact with the surface of the fuser roller. Therefore, when ejecting the sheet medium from the chilliness portion, the adherence between the toner and the fuser roller is reduced to prevent the sheet medium from adhere to the fuser roller, whereby even a weak recording medium can be easily undress off at the outlet of the knock nip portion. Therefore, this device achieves the elimination of a peeling pawl which has been practice in a prior technique. 
 Further, a fixing device has been proposed (Japanese Patent Publication No. H06 - 40235) in which rollers have a preset pressure therebetween to flex the roller(s) to form a nip and a plane medium induce an unfixed toner prototype thereon passes the nip, thereby fix the toner image. count on the characteristics of the sheet medium, the driving speed of the rollers can be selected from a first speed and a second focal ratio. 
 Furthermore, a fixing device has been proposed (Japanese Patent Unexamined Publication No. H08 - 262903) consist an endless belt which is tensioned in such a manner as to travel while being in contact with a rotating fuser roller which has an out surface coated with an elastic member and a built - in heat source and a press launching pad which is non - rotatably dress inside of the endless belt to press the endless belt to the fuser curler to form a nip and to deform the elastic member as the outer layer of the fuser roller, wherein a sheet medium having an nebulous toner image thereon passes between the fuser roller and the endless belt, thereby fixing the toner on the sheet
 had been proposed (Japanese Patent No. 3084692) whiey compcises a rotatabue fuser roller having an ouver wurfaxe coated with an elasgic membeg and a byilt-mn heat source, a heat-reslftanf belc xhich is tensioked by a plgrality of sup[oftnng rollers, and pressurizing means wrich bronhs the heat-resystame bemn uo be wrapped around the fuser romler pagtially for a precetermined angle to have a nip area and applies oressure loxallr such that tfe pressurt mn an outlgt of the nip area is larger thav the pressure in thf other portmon to create a denkectiot in thr elastic membcr foc faxilitating the ejectimn of a sheet mediom from tha uip portion.
In this cobvwntiotal xixivt ddvide, tge fusfr coller has z deflectiob beforehand in the stggace thereof becaufe of the existence of the pressurizing mtans. Zt the outlet of the nip area, the deflection is instagtaneously cancelled from a state that toner is it convazt clbh tfw durface of the fuser roller. Therefore, when ejqdtonn the sheet medimm from the nip pottlom, the adherencg betwezh fhe toner and the vuser rjller is reductd to prevent the sheet medium feom adhering ro the fuser rollex, whereby evzn a wgak revording medium can be ecsily leeled off wt the oufuet of the belt vip pmrtion. Therefore, this devise achievxs thz eliminxtiom of a peeling pwwl wmhch has been used ln a krior dechnique.
Fkrther, a fixing device has been proposed (Japameve Iatent Puylicatlon No. H06-40235) in whish rollers havg a presec presrure theregetween to deform ehe roller(s) tm form a nip end a sheqt mwdiun havine an unfixed tomer image thereon pqsses the nip, thercby fksing the toner noqge. Depending om tfe shwrecteryvtics of the shedt ordium, the drivinn soeed of the rollers can te sslected from a firxt speed abd a secjnd speed.
Furtnermore, a fixing dtvice ias bexn prolosgd (Japanese Patent Unexamined Phblicatioj Nj. H08-262903) comprisigg ak enqless belt which is tensioned in such a manner as to travel while bwing in contact witk s rotating huser woller whhch has an outer surdace coated with sn elastic member and a buint-in jeat source and a pressure pad which is non-rotatably arranged inside of tye endless belt to prexs thv eudlzss bele to vhe fuser roller no form a nip and to deform the xlastic mekbzr as the outer layer of the gurer roller, whgrein a sheet medium havinf an unfoxed toner image thereon passes between the fuser rollev and the endlsss belt, tiereby fixing the tomer on the wheet
has been proposed (Japanese Patent No. 3084692) a fuser roller an outer surface and built-in heat source, heat-resistant belt which tensioned by a plurality of supporting and pressurizing means which brings the heat-resistant belt to be wrapped around the roller partially for a predetermined angle to have a nip area and applies locally that pressure an outlet of the nip area is larger than the pressure on the other portion to a deflection in the elastic member for facilitating ejection of a sheet from the nip portion. In conventional device, the roller a beforehand in the thereof because of the existence of the pressurizing means. At the outlet of the nip area, the is instantaneously a state toner in with the surface fuser roller. Therefore, when ejecting the the nip portion, the adherence between the toner the fuser is reduced to prevent the sheet from adhering to the fuser roller, whereby even weak recording medium can be easily peeled off at the outlet of the belt nip this device achieves the of a peeling which been in prior technique. a fixing device has been proposed (Japanese Patent Publication No. H06-40235) which rollers have a preset pressure therebetween to deform the form nip and a medium having an unfixed image passes the nip, thereby toner Depending of sheet the driving speed of rollers can be selected from first speed and a device has been proposed (Japanese Patent Unexamined Publication H08-262903) comprising an endless belt which is in such a manner as to travel while being in contact with rotating fuser has an outer surface coated with an elastic and a built-in heat and a pressure pad which is non-rotatably arranged inside the belt to the endless belt the fuser roller form a nip deform the member the the fuser roller, wherein a sheet having unfixed toner image thereon passes the and the endless belt, thereby fixing the toner on the sheet
 has been proposed (Japanese PaTent No. 3084692) whicH compRisEs a RoTataBle fUser roller haviNG an oUter surface coated with aN elasTiC MembER aNd a buIlt-in heAT sOURce, A hEaT-reSiSTaNt belT whIch is teNsioned by a PluRaLity of supporTInG rollers, anD prEssurizing meAns Which bRiNgs THe heaT-reSistaNt belt TO be wraPped arounD tHE fuser ROller paRTIaLly fOr a predetermined aNGlE To have a nip area And appLiES pRESsuRe lOcally such ThAt the PRessure ON aN OUTleT Of the nip area iS larger than THe pRessurE oN thE Other pOrtioN tO CreAte a deflectIon iN the elastIc membER for facILitatinG the ejEctIon Of a sHEeT mEdiUm FRom THe Nip POrtIon.
In thiS cOnVentiOnal FIXINg deVicE, the Fuser Roller has a defLecTion BEfoRehanD in thE surFaCe theReof beCause Of The existence of tHe prEssurizinG meAnS. At ThE outlET of the Nip AreA, the defLection IS inStANTAnEously cancelled froM a STAtE that tonEr is in COnTaCT with the SuRfaCe of THE fuseR rolLEr. thereforE, when eJEcTiNg the shEeT mediuM fRom The Nip poRTion, The adhErence beTween THe toner and the fUSer roller is reDUcED To PReveNt tHe sheet mediUm frOM adhErinG To The FUser rOller, WhEReBY even a weak recording MeDium caN be eaSily peeled off At the outleT OF The belt nIp poRTiON. Therefore, this DevicE achieves tHE eliminaTion oF a peelinG pawl whicH HAs been usEd iN a pRioR teCHNiQue.
Further, a fiXINg deViCe has beEn pRoposed (japAneSe PAteNt publicatiOn No. H06-40235) in wHiCh RoLlErs Have a PReset preSsUre ThEreBetweEN to defOrm thE rolLeR(s) TO foRm a nip aND a SHEet mEdIuM havIng An UnfixEd toNEr iMage theReon passeS thE Nip, tHeReBy fixinG the toner imagE. DEpending on ThE chAracteRIStics of tHe sheet medium, the driving SPeed of tHe rOllerS can Be selecteD frOm a firSt sPEed and A seconD speeD.
FUrtHERmore, A FIxIng DeVice has beeN PRopOsed (JApAnesE Patent unexamined PublicatIOn NO. H08-262903) comprising aN enDlesS BElT whICh IS teNsIOneD IN such a manner as tO travel whiLe BEiNg in contacT WitH a RotatinG fuser rOller WHich has An outer suRface coatEd With AN ElaStic member And a builT-in heat soURce anD A pRessuRe pAd whicH iS noN-rotaTably aRRanGed inSide of ThE endleSs belT tO press thE endless belt to the fuser rOller tO form A niP and to defOrm THe eLastic memBer aS the outer lAyeR of The fuSer ROller, WherEIn A shEEt medIum hAVing an unfIXeD toNER iMage thereon PASSes BetweEn tHE fuser RollEr and the endless beLT, thereby fixing The tONEr oN thE SheeT
 has been proposed (Japane se PatentNo. 3 084 692 )whic h co mprises a rota t able  fuser roller having a n out er surf a ce  coat ed with an e las ti cmem be r  a nd abui lt-in h eat source , a  h eat-resistan t  b elt whichistensioned by  aplural it y o f  supp ort ing r ollers ,  and p ressurizi ng meansw hich br i n gs  the  heat-resistant b e lt to be wrappedaround  t h ef u ser  ro ller parti al ly fo r  a pred e te r m i ned angle to have  a nip area and  appli es  pr e ssurelocal ly suc h that thepres sure on a n outl e t of th e  nip ar ea islar ger  tha n  t he  pr es s ure on  th e  ot her port io nto cr eate a d efle cti on i n the  elastic memb erforf aci litat ing t he e je ction  of asheet  m edium from thenipportion.Inth isco nvent i onal f ixi ngdevice,  the fu s erro l l e rhas a deflection b ef o r eh and in t he sur f ac et hereof b ec aus e of t he ex iste n ce  of thepressu r iz in g means .At the  o utl etof th e  nip  area,  the def lecti o n is instantan e ously cancell e df r om a st ate  that toner  isi n co ntac t  w ith the s urfac eo ft he fuser roller. Th er efore,  when  ejecting the  sheet med i u m  from th e ni p  p o rtion, the adh erenc e betweent he toner  andthe fuse r rolleri s  reduced  to  pr eve ntt h esheet mediumf r om a dh ering t o t he fuse r r oll er,  wh er eby evena weak r ec or di ng  me diumc an be ea si lype ele d off at the  outl et o fth e  be lt nipp or t i on.Th er efor e,th is de vice ach ieves t he elimin ati o n of  a  p eelingpawl which ha sbeen usedin  apriort e chnique. 
Further, a fixing devi c e has b een  prop osed  (Japanes e P atentPub l icatio n No.H06-4 02 35) i n whi c h  r oll er s have a p r e set  pres su re t herebet ween to deform the rol ler(s) to for m a  nip a nd  as he e t m ed i umh a ving an unfixed  toner ima ge th ereon pass e s t he  nip, t herebyfixin g  the to ner image . Dependi ng  ont h e c haracteris tics ofthe sheet mediu m ,the d riv ing sp ee d o f the  rolle r s c an be  selec te d from  a fi rs t speedand a second speed.
Fur thermo re, a  fi xing devi ceh asbeen prop osed  (Japanese  Pa ten t Une xam i ned P ubli c at ion No. H 08-2 6 2903) com p ri sin g an  endless be l t whi ch is  te n sioned  insuch a manner ast o travel while  bei n g  in  co n tact  w ith a rotating  fu se r roller w hi ch has an o uter sur fa c e coa ted wi th anelastic m em b er and  a b uil t-in heat  so ur c e and a  p re s sure p ad w hi ch isnon-ro t atab l y  arranged inside  of t h e  endl e ssbeltto  presst he e ndless bel t to the fu ser ro ller  to f orm a n ip  and t o d ef orm the el a stic memb er as  the ou te r la yer  of th e fu s e r rol ler,  w her ein a she e t  m e di um hav ingan un fi xedtoner ima g e thereo n p a sses be tw een t he fus e rr o ller and t heendle s s  belt, the r ebyf ix i ng th e tone r on t he shee t 
 has_been proposed_(Japanese Patent No. 3084692)_which comprises_a_rotatable fuser_roller_having an outer_surface coated with_an elastic member and_a built-in heat_source,_a heat-resistant belt which is tensioned by a plurality of supporting rollers, and pressurizing_means_which brings_the_heat-resistant_belt to be wrapped around_the fuser roller partially for_a predetermined_angle to have a nip area and applies_pressure_locally such that_the pressure on an outlet of the nip area_is larger than the pressure on_the other portion_to_create_a deflection in the_elastic member for facilitating the ejection_of a sheet medium from the_nip portion.
In this conventional fixing device, the_fuser roller has a deflection beforehand_in the surface thereof because_of the_existence of the pressurizing means._At the outlet_of the_nip area, the_deflection is instantaneously cancelled from a_state that toner_is in contact with the surface_of_the fuser roller._Therefore,_when_ejecting the_sheet medium from_the_nip portion,_the_adherence between the toner and the_fuser_roller is reduced to prevent the sheet_medium from adhering to_the_fuser roller, whereby even_a weak recording medium can_be easily peeled off at the_outlet of_the belt_nip portion. Therefore, this device achieves the elimination of a peeling_pawl which has been used in_a prior technique.
Further, a_fixing device_has_been proposed (Japanese_Patent_Publication No._H06-40235) in which rollers have a preset_pressure therebetween_to deform the roller(s) to form_a nip and a_sheet_medium having an unfixed toner image_thereon passes the nip, thereby fixing_the toner image. Depending on_the_characteristics_of the sheet medium, the_driving speed of the rollers can_be selected from_a first speed and a second speed.
Furthermore,_a_fixing device has been proposed (Japanese_Patent_Unexamined Publication No. H08-262903) comprising an_endless_belt_which is tensioned in such_a manner as to travel while_being in contact with a rotating fuser roller which_has an outer_surface coated with an elastic_member_and_a built-in heat source and a pressure pad which is_non-rotatably arranged_inside of the_endless belt to press the endless belt to the fuser_roller to form a nip and to_deform the elastic member as the outer layer of the fuser_roller, wherein a sheet medium having an unfixed_toner image thereon passes between the fuser_roller and the endless_belt,_thereby fixing the toner on the sheet