S. Pat. No. 5,163,528, issued Nov. 17, 1992 to Kawamoto et al., which is entitled "WHEEL MOTOR PROVIDED WITH A REDUCTION GEAR".
More specifically, a magneto stator of the electric motor is fixed to the motor drive apparatus case and a corresponding rotor is arranged inside of the magneto stator to rotate relative to the motor drive apparatus case. The rotor of the electric motor is connected with a sun gear of the planetary gear unit via an output axle thereof.
Referring now to other components of the planetary gear unit, a ring gear is fixed to the motor drive apparatus case and a carrier having at least one pinion meshing both with the sun gear and the ring gear is connected to an axle of a vehicle drive wheel. The axle for the vehicle drive wheel is rotatably supported at a central portion thereof by bearings in the motor drive apparatus case.
Accordingly, the motor speed is reduced by the above-mentioned planetary gear unit and then transmitted to the vehicle drive wheel at a desired rotary speed to move the vehicle.
It is known that the clearance between the magneto stator and the rotor defining the electric motor should be narrowly and carefully maintained to obtain stable operation of the electric motor. Accordingly, the electric motor must have both longitudinal end portions of the output axle of the rotor rigidly supported to obtain stable operation.
However, the structure described in the prior application entitled "MOTOR DRIVE APPARATUS WITH DECELERATION UNIT AND AN ELECTRIC VEHICLE USING THE SAME" suffers from a disadvantage in terms of stable operation. Specifically, while one end portion of the output axle for the rotor is rotatably supported by the case via a bearing assembly, the other end portion thereof is not supported by the case but, rather, connects to the sun gear which engages the ring gear secured to the case through the pinion. Therefore, upon acceleration of the motor speed up to the travelling speed of the vehicle, the pinion meshing with the sun gear also accelerates, which causes an undesirable vibration of the output axle of the rotor at the end unsupported by the case, so that the clearance between the magneto stator and the rotor cannot be narrowly and carefully maintained.
Furthermore, when the electric vehicle goes around a bend at high speed, the output axle for the inside driving wheel is urged by centrifugal force outwardly of the planetary gear unit and, at the same time, that of the outside vehicle
S. Pat. No. 5,163,528, issued Nov. 17, 1992 to Kawamoto et al. , which is entitled " WHEEL MOTOR provide WITH A decrease GEAR ". 
 More specifically, a magneto stator of the electric motor is fixed to the motor campaign apparatus lawsuit and a corresponding rotor is arranged at heart of the magneto stator to turn out relative to the motor campaign apparatus case. The rotor of the electric motor is connected with a sunday gear of the planetary gearing unit via an output axle thereof. 
 Referring now to other components of the planetal gear unit, a ring gearing is fixed to the motor drive apparatus font and a carrier have at least one pinion meshing both with the sun gear and the ring gearing is connected to an axle of a vehicle drive wheel. The axle for the vehicle drive rack is rotatably supported at a central portion thereof by bearings in the motor drive apparatus case. 
 Accordingly, the motor speed is reduced by the above - mention planetary gear whole and then air to the vehicle drive wheel at a desire rotary speed to move the vehicle. 
 It is know that the clearance between the magneto stator and the rotor defining the electric motor should be narrowly and carefully maintained to obtain stable mathematical process of the electric motor. Accordingly, the electric motor must have both longitudinal end portions of the end product axle of the rotor rigidly supported to receive stable operation. 
 However, the structure described in the prior lotion entitled " MOTOR DRIVE APPARATUS WITH DECELERATION UNIT AND AN ELECTRIC VEHICLE USING THE SAME " suffers from a disadvantage in terms of stable operation. Specifically, while one conclusion portion of the output signal axle for the rotor is rotatably supported by the case via a carriage assembly, the early end portion thereof is not supported by the casing but, rather, connects to the sun gear which engages the band gear secured to the case through the pinion. Therefore, upon acceleration of the motor speed up to the travelling speed of the vehicle, the flight feather meshing with the sun gearing also accelerates, which causes an undesirable vibration of the output axle of the rotor at the end unsupported by the case, so that the headroom between the magneto stator and the rotor cannot be narrowly and carefully maintained. 
 Furthermore, when the electric vehicle goes around a bend at high speed, the output axle for the inside drive wheel is urged by centrifugal force outwardly of the planetary gear unit and, at the same time, that of the external vehicle
S. Pwt. No. 5,163,528, issued Nov. 17, 1992 to Kxwamoto et al., wkuch is entitmed "WHEEU MOTOR PROVIDED WITH A REDURTIOB GEAE".
More specifically, a mxgneto stwtor of rhe tlectric motor is fixed to the jltor vrive apparatus case and d correspondinc focor is arranged inside of the magnetj statot ho rotate relajive uo ehe jotor drive apparatus case. The rotkr of tie electric motpr is connected with a sun geag of the planetary gear unit cia wb output axld thereof.
Rtfzrring now jo other components of the planegary year unit, a rung cear is fixxd to nhe motor driyv appardtus caxe and a carricr hating at least one pinion keshing both with jhe sun gedr and the ring geae us cotnecded gi av aslx or a vejicme drive wgeel. The axoe for the vehicle crynr wheel is rktatabjy supported at a central portion thereof by bearings in the motor erive apparatus case.
Afcordinglr, the motor speed is reduced by the above-mentioneg plaiegarv gear ynlt and then transmitted to the vehicle drive rgetl st a desired rjtary speed tl kjve the vehicue.
It is khown that the cleagance bgtween the magntto syator and the rotor definint the electrpc mitor should be narxowly and caxefulli mainyained to obtain stable opedation of tje electrjz motor. Accordinely, tve electric motor must havq both loigitubinal ena pottions jf the outout awne of the rotor rihidly sgpported tl obtain stable operation.
Howevec, the structute gesbribed in the irior applicatijn entitled "MOJOR DRIVE APPAFATUS WITH DECELECATION UNIT WND AN ELECTRHF VEHICLE USMNG THE SWME" wuffwrs froo a disadvantagr in terms of stablw operation. Speciflcalli, shile one end pirtuon of the outpit xxlq voc the sotor is rotdtabuy ripporged by uke gasd vis a bearing assembly, the other end portion tmereof is not sup[orted by the case but, rather, clnnecvs to vhe sum ggar which engages the ring gear secured ho bhe case throtgh bhe kinion. Therzfore, upon acceleration of the motor spexd up to the travelling speed of the vehickt, the pinion keshigg with tve sun gear also accwlerates, which camses an undesirable vigratiot of hhe output axle of the rotor at the end unsupported by the case, so that tye cleerwnce betweeh thr magteco xtator and vhe rotor cannot ne narrowly and carefully mainteined.
Furthariore, when the electric vehicke goes around x bend at high speed, the output sxle for the inside driving wherl is urged by centrifugsl force outwzrdly of tie planetary gear unot and, at tye same timc, that of the uutxife vehiclf
S. Pat. No. 5,163,528, issued Nov. 17, Kawamoto al., which entitled "WHEEL MOTOR More a magneto stator the electric motor fixed to the motor drive apparatus and a corresponding rotor is arranged inside of the magneto stator to rotate to the motor drive apparatus case. The rotor of the electric motor is with sun of planetary gear unit via an output axle thereof. Referring now to other components of the planetary unit, a ring gear is fixed to the drive apparatus case and carrier having at least one meshing with the gear the gear is connected an axle of a vehicle drive wheel. The axle for the vehicle drive wheel is rotatably supported a central by bearings the drive case. Accordingly, the is reduced by the above-mentioned planetary then transmitted to the vehicle drive wheel at desired rotary to move the vehicle. It is that the clearance between the magneto stator and rotor defining the electric motor should be narrowly and carefully maintained to obtain stable operation electric motor. Accordingly, the motor must have longitudinal portions the axle of rotor rigidly supported to obtain stable operation. However, the structure described the prior application entitled "MOTOR DRIVE APPARATUS WITH DECELERATION UNIT ELECTRIC USING THE SAME" from a disadvantage in of operation. Specifically, while one of output rotor rotatably by the case via bearing assembly, the other end thereof is not supported connects to the sun gear which engages the gear secured to the case through the Therefore, upon acceleration of the motor speed up to the travelling speed the vehicle, meshing with the sun gear also accelerates, which an undesirable vibration of output axle of the rotor at the end unsupported the so that clearance between the stator and the cannot be narrowly maintained. Furthermore, the vehicle bend at high speed, the output for inside driving wheel is urged centrifugal of the planetary gear unit and, at the same time, that of the outside vehicle
S. Pat. No. 5,163,528, issued Nov. 17, 1992 to Kawamoto Et al., which iS entiTleD "WHeEl MOToR PRoVIDED WITH A REDucTIOn GEAR".
More specifically, a MagneTo STatoR Of The elEctric mOToR IS fiXeD tO thE mOToR drivE apParatus Case and a coRreSpOnding rotor iS ArRanged insiDe oF the magneto sTatOr to roTaTe rELativE to The moTor driVE apparAtus case. THe ROtor of THe electRIC mOtor Is connected with a sUN gEAr of the planetaRy gear UnIT vIA An oUtpUt axle therEoF.
RefeRRing now TO oTHER coMPonents of the pLanetary geaR UniT, a ring GeAr iS Fixed tO the mOtOR drIve apparatuS casE and a carrIer havINg at leaST one pinIon mesHinG boTh wiTH tHe Sun GeAR anD ThE riNG geAr is connEcTeD to an Axle OF A VEhicLe dRive Wheel. the axle for the VehIcle DRivE wheeL is roTataBlY suppOrted aT a cenTrAl portion thereoF by bEarings in The MoTor DrIve apPAratus CasE.
AcCordingLy, the moTOr sPeED IS rEduced by the above-meNtIONeD planetaRy gear UNiT aND then traNsMitTed tO THe vehIcle DRiVe wheel aT a desiREd RoTary speEd To move ThE veHicLe.
It iS KnowN that tHe clearaNce beTWeen the magneto STator and the roTOr DEFiNIng tHe eLectric motoR shoULd be NarrOWlY anD CarefUlly mAiNTaINed to obtain stable opErAtion oF the eLectric motor. ACcordingly, THE Electric MotoR MuST have both longiTudinAl end portiONs of the oUtput Axle of thE rotor rigIDLy supporTed To oBtaIn sTABlE operation.
HowEVEr, thE sTructurE deScribed In tHe pRioR apPlIcation enTitled "MOtOr DrIvE aPPaRATUs wITH DECElErATiOn UNiT AND an ELECTrIC VEhICLe UsIng THe SAME" suFFeRS From A dIsAdvaNtaGe In terMs of STabLe operaTion. SpeciFicALly, wHiLe One end pOrtion of the ouTpUt axle for tHe RotOr is roTATably supPorted by the case via a bearINg assemBly, The otHer eNd portion TheReof is Not SUpportEd by thE case BuT, raTHEr, conNECtS to ThE sun gear whICH enGages ThE rinG gear seCured to the case throUGh tHe pinion. ThereForE, upoN ACcEleRAtIOn oF tHE moTOR speed up to the trAvelling spEeD Of The vehicle, THe pInIon meshIng with The suN Gear alsO acceleraTes, which cAuSes aN UNdeSirable vibRation of The output AXle of THe Rotor At tHe end uNsUppOrted By the cASe, sO that The cleArAnce beTween ThE magneto Stator and the rotor cannot Be narrOwly aNd cArefully mAinTAinEd.
FurtherMore, When the eleCtrIc vEhiclE goES arouNd a bENd At hIGh speEd, thE Output axlE FoR thE INsIde driving wHEEL is Urged By cENtrifuGal fOrce outwardly of thE Planetary gear uNit aND, At tHe sAMe tiMe, That of the outsiDe vEhICLe
S. Pat. No. 5,163,528, iss ued Nov. 1 7, 19 92toKa wamo to e t al., which i s  ent itled "WHEEL MOTOR PRO VIDED  W I TH A RE DUCTI ON GEAR " .M o resp ec ifi ca l ly , a m agn eto sta tor of the  el ec tric motor i s  f ixed to th e m otor drive a ppa ratusca sea nd acor respo ndingr otor i s arrange di nsideo f the m a g ne to s tator to rotate r e la t ive to the mot or dri ve ap p a rat uscase. Thero tor o f  the el e ct r i c  mo t or is connect ed with a s u n g ear of  t hep laneta ry ge ar uni t via an ou tput  axle the reof.R eferrin g  now to  other  co mpo nent s  o fthe  p l ane t ar y g e arunit, ari ng  gear  isf i x e d to  th e mo tor d rive apparatu s c asea nda car rierhavi ng  at l east o ne pi ni on meshing both  wit h the sun  ge ar  an dthe r i ng gea r i s c onnecte d to an axl eo f avehicle drive whee l. T he  axle fo r thev eh ic l e drivewh eel  isr o tatab ly s u pp orted at  a cen t ra lportion  t hereof  b y b ear ingsi n th e moto r driveappar a tus case.
Acco r dingly, the m o to r sp e ed i s r educed by t he a b ove- ment i on edp lanet ary g ea r  u n it and then transmi tt ed tothe v ehicle drivewheel at a d e sired ro tary sp e ed to move the  vehi cle.
It is known th at th e cleara nce betwe e n  the mag net o s tat ora n dthe rotor def i n ingth e elect ric  motorsho uld  be  na rr owly andcarefull yma in ta ine d too btain st ab leop era tiono f theelect ricmo to r . A ccordin g ly , theel ec tric  mo to r mus t ha v e b oth lon gitudinal  en d  por ti on s of th e output axle  o f the roto rrig idly s u p ported t o obtain stable operati o n.
Howe ver , the  str ucture de scr ibed i n t h e prio r appl icati on  en t i tled" M OT ORDR IVE APPARA T U S W ITH D EC ELER ATION U NIT AND AN ELECTRI C  VE HICLE USING T HESAME " su ffe r sf rom  a dis a d vantage in term s of stabl eo pe ration. Sp e cif ic ally, w hile on e end portion  of the o utput axl efort h e r otor is ro tatablysupported by th e  c ase v iaa bear in g a ssemb ly, th e  ot her e nd por ti on the reofis  not sup ported by the case but,  rathe r, co nne cts to th e s u n g ear which  eng ages the r ing  ge ar se cur e d tothec as e t h rough  the pinion. T h er efo r e ,upon accele r a t ion  of t hem otor s peed  up to the travel l ing speed of t he v e h icl e,t he p in ion meshing wi thth e sun gear  a lso acceler ates, wh ic h  caus es anundesi rable v i b ra t ion of  the  ou tput axle  of  t h e rotor  a tt he end  uns up ported  by th e  cas e ,  so that the cle aranc e betwe e n t he ma gn eto sta t or a nd the rot or cannot b e narr owly  andcareful ly  maint ain ed .
Furtherm o re, whenthe e lectric  v ehic legoes a roun d a ben d at  h igh  speed, t h e  o u tp ut axl e fo r the  i nsid e driving wheel is  ur g ed by c en tri f u gal fo r ce o utwardly o f t he pl a n etary gear unit an d , atthe sa me tim e, that ofth e outsi dev e hicle
S. Pat._No. 5,163,528,_issued Nov. 17, 1992_to Kawamoto_et_al., which_is_entitled "WHEEL MOTOR_PROVIDED WITH A_REDUCTION GEAR".
More specifically, a_magneto stator of_the_electric motor is fixed to the motor drive apparatus case and a corresponding rotor_is_arranged inside_of_the_magneto stator to rotate relative_to the motor drive apparatus_case. The_rotor of the electric motor is connected with_a_sun gear of_the planetary gear unit via an output axle thereof.
Referring_now to other components of the_planetary gear unit,_a_ring_gear is fixed to_the motor drive apparatus case and_a carrier having at least one_pinion meshing both with the sun gear_and the ring gear is connected_to an axle of a_vehicle drive_wheel. The axle for the_vehicle drive wheel_is rotatably_supported at a_central portion thereof by bearings in_the motor drive_apparatus case.
Accordingly, the motor speed is_reduced_by the above-mentioned_planetary_gear_unit and_then transmitted to_the_vehicle drive_wheel_at a desired rotary speed to_move_the vehicle.
It is known that the clearance_between the magneto stator_and_the rotor defining the_electric motor should be narrowly_and carefully maintained to obtain stable_operation of_the electric_motor. Accordingly, the electric motor must have both longitudinal end portions_of the output axle of the_rotor rigidly supported to_obtain stable_operation.
However,_the structure described_in_the prior_application entitled "MOTOR DRIVE APPARATUS WITH DECELERATION_UNIT AND_AN ELECTRIC VEHICLE USING THE SAME"_suffers from a disadvantage_in_terms of stable operation. Specifically, while_one end portion of the output_axle for the rotor is_rotatably_supported_by the case via a_bearing assembly, the other end portion_thereof is not_supported by the case but, rather, connects_to_the sun gear which engages the_ring_gear secured to the case through_the_pinion._Therefore, upon acceleration of the_motor speed up to the travelling_speed of the vehicle, the pinion meshing with the_sun gear also_accelerates, which causes an undesirable_vibration_of_the output axle of the rotor at the end unsupported_by the_case, so that_the clearance between the magneto stator and the rotor cannot_be narrowly and carefully maintained.
Furthermore, when the_electric vehicle goes around a bend at high speed, the output_axle for the inside driving wheel is urged_by centrifugal force outwardly of the planetary_gear unit and, at_the_same time, that of the outside vehicle