CA1320852C - Engine/transaxle combination - Google Patents

Abstract

ENGINE/TRANSAXLE COMBINATION
Abstract of the Disclosure A unitized engine transaxle combination preferably having a variable speed transmission such as a hydrostatic or continuous variable transmission for utilization in a work vehicle, the combination including a specific arrangement of components parts inside the transaxle housing and the connection of the engine thereto to provide the engine transaxle combination unit. In the preferred embodiment, a hydrostatic pump is connected to the engine and the hydrostatic motor is positioned inside the transaxle housing on the same side thereof in relation to the left or right side of the combination. In close proximity to the hydrostatic motor, a speed reduction unit is also housed inside the transaxle housing. The other end of the transaxle housing houses a differential unit. The hydrostatic pump is driven by a cam gear mechanism which is contained within the engine housing and interconnects with the engine crankshaft and the hydrostatic pump input shaft so that the hydrostatic pump is driven thereby. Preferably, the engine and the transaxle are interconnected and include at least a partially common housing. The engine is positioned as close to the ground and as close to the transaxle as possible in order to lower the vehicle's center of gravity while still providing sufficient clearance between the output end of the engine crankshaft and the ground. A single belt is utilized to drive a working implement operatively connected to the vehicle from the engine output shaft to an implement input shaft. This single belt passes through a space created in the transaxle by the arrangement of the component parts as described above. The space created is sufficient to allow the vehicle to operate the implement with a maximum vertical float which occasionally, but not for extended periods exceeds the recommended manufacturer's belt misalignment angle without interference between the belt and the bottom of the transaxle housing.

Description

i ~3208~2 ENGINE/Tl~ A~E ~O~IIJATION
B~ctro~ th~
The pr~3ent lnven~ion ~ela.t~: ko engine/trAn~:axle~
co~inat~on~: u ed as driv~n~ mean~3 ~or wo~cing v.eh~ol~g.
~I~.. 2 ~hows a cc~nvention~l working vehiale 1~ ~quipped ~or l~n mowin~. l~e c::~nven~onal wo~k ~ehic:le 10 int:ludes a ~teering whe~l 11, an op~xa~or`~ ~e~ 13 and a mower deo2c 16 or other worX~n~ i~nplemen~ whis~h i~ con~rention~lly opera1~i~ely aor~c~e~ to ~he v~hi~le ~hroug~ ~wo triE~ion ba~s 17r ~. A
lO dri~ unit 20 which in~luda~ an ~ng~n~ ~l is pos~t~oned betwe~ th~ t~o ~ront wheel~ ~2 an~/or ~wo rear w~eals 24. A~;
~hown, ~ con~rentiorlal trans~xl~ Z~ is po~t~on~d on tho mower de~k 1~ ~ide of the ~e~ wheel~ 24. Dri~ving pc)wer is p~o~ed from t~e engine ~l to the mower aeak l~ A Y-belt ystem ~8 1~ i ope~ca~i~ely posi~ioned batween th~ engine 2l and ~h~ m~wer d~c~k 16 for transmittin~ power from the en~inç~ 21 ~o th~ mower deck 16 or other implemen~.
In the c l portion 30 o~ t~he tr~n~;a~ele, a spe~d re~u~tion un~ ~ a~d a di~erential unit ~rlot ~hown~ ~re ~0 ope~ati~el~f po i~ioned in c~o~e prox~ity to e~c:b o'cher, a~
~hown in ~apane~e Patent un~xamirled pu~ ation Nc~. 5~-2306~.
In the coI~entional s~uq~ , a first V-~elt 3~ ro~i~ed ~or t~n~mi~tinçl p~wer be'cween a ~elt pull~ 33 o~ra~i~ely ~onneo~ed to ~he ou~pu~ end o~ en~ine arank~ha~ 34 and a ~5 seGond belt pull~y 3~ operati~e~y connecl:~d to an interm6~di~te sh~S 38 w3~ich is oonven~io~lly c~onn~cste~ to th~ tran:~:axl~
~$. A ~ ond V~ 40 i~; provid~ or 'cr~n~mit~ powe~
b~ween i~ ~hir~ bel~ pulley 41 o~erat~rely ~on~o~ed to the anten~ediake ~ha~ and ~ ~our~ pull~r 42 ~perati~ly 30 conn~ed ~o ~he 'npu~ ~ha:æ~ 43 o~ the llacnser ~ck lS or working i~npledn~nt.
With t;h~ con~ e~, thQ i~ t~ ~h~ft 38 having th~ ~:econd 36 z~nd ~hird ~1 pu~leyc is res~uir~d ~ecause the rela~ve ~hickn~3 o~ the central pvrt~ on 30 o~ the 3~ con~en~ional tr~ns~xle pre~ents~ ~:he mo71~r deck 16 or o~er a~taohed ~plement~ fro~ having ~u~1c~ient ope~iona~
rerti~al mo~rement ~r ~oak rela'ci~e ~o ~h~ ~ork v~icl~.

13208~2 Ther~vre, utilizing a sin~l~ V-belt b~ween the enyin~ outp~t sh~t 34 a~d the iT~ut ~ t 43 of ~he worl~ ~npl~ent ~o tran~t pow~x i8 no~ pr~ical ~e~au~a ~ aonven~l~nal in~exYned~a~e sha~t 38 wit~ pulleys pr~ride~s ~e ability for s the V~belt ~nnesting ~he ir~ diatæ sha~t and th~ imple~e~t to ~loat v~rtically in respon~ ~o s:onvex or c:oncaYe aondîtion~: in the vperatia~g ~ur~ac~ witho~t inter~er~nae ~etwe~n ~h~ belt and th~ ~c)nven~i~nal thic:Jc t~an~a~le ho~ ~n~ Specifi~ally~ as shown, wi~ nte~ediate ~ha~t o 3~, ~f ~he mower de~k 16 i~ ved ~rertirally, the ~;ec:on~ V-bel~ 40 will ~no~e ve~ically9 3~u~ 1:he i~irst ~-~elt 32 will not mo~e ~ertically. qh~refor~, w~t:h t2~ con~entional co~:tructic~n, the c~n~ral thic:k portion ~o c~ l:he ~r~nS!axle i~
preven~ed ~rom ~o~ta~tîng o~ interfering wî~h the ~ir~t Y-belt 15 32.
Ho~evex, in the a~ove ~e~c:ri~ on~exl~ion~l ~;trua~u~e th~ tan~e bet~7~en the ~ nt~ diate, sh2ft 3~ ar~A ~e implem~nt inpu~ shat 43 is ~ela~ively short an~l tbQ 8e~:0nd V-belt 40 will xeach ~s maxim~m acc:~pta~le ~elt n~i~al~ nt 20 angl~ 5~ ~o) for ex~ended ope;ration~: with ra~h~ar l~ted vartical mo~ement of the ~wer d~k 1~ when ~o~pared ~o the vertical moYe~Pant possi~le ~ utilizi21lg a long~r ~lt. Thu~, becau~ of the co2~ention~1 transaxl~ :3tx~achlr~, t~o b~lt~ an~
an în~ ediate s:haft and pull~ys~ ~rQ r~uire~l resultinçl in 25 i~ar~as~d cost and ~mplexit~ft no~ t~ me~ation ~he re~trict~d ver~i~al flo~ ur~ r ~h2 c~nv~sn~i.on~l ~o ~ sy~t~ is a~paren~ly subjecte~ to in¢rea~;ed k~A~lins~ ~e~ns:y thereby xe~ul~ing in re~u~ed ~ervi~e li~e~; ~Eor the V-~lt~.
In order to increase ~h~ ~ctual Yertic~ floa~ di~tan~e, 30 it ap~ear~ nece~:~;ary to in~:rea ~ the di~ nc~ om t~e en~ne ou~put sha~ pulley to ~he ~mpl~hent input ~h~t pull~y in order to in~::r~e the di~t;E~nc~ ab~tre and ~elow the r~o~nal ~ level i~pl~m~nt position whi~}l the iDIpl~ent ~n 1c~at. ~hi~ ~
~s due ~o the a~c~p~able b~lt mi~3~lig~n~ angl@ men~lon~d 35 ab~3 Sp~c:ifically, as the distanc~ on ~h~ engln~
output c~a~cs~aft pulley and the iml?lem~t inp~ pull~y decr~a~e~, the ~mall~r ~he di~t~Lnc~a a~ 2md below the no~al le~rel implQment posit~on ~ impl~en'c ~an ~loat ~hout exaeeding the 3~alt ~ aligs~ment an~lQO Bec~u~e w~

A

1321)8~2 co~ven~ional pulley ~nd belt ~yE;tem u~ ed to tran~mit pow~r from ~h~3 engine ou~put ~ranXsh~ o the i~pl~3m~n~ inpu~ ~ha~t havin~ tw~ pulleys ~nd an intex~dl~t~ sha~ he c:onventional ~y~ xe~tricted r~lative to 1:h~ ~lt`~ ali~ t ~ngl~
5 a~v~ ~n~ below khl3 i~plement le~el plane. In oth~3r wor~
the ~horte~ the di~noe OI any one b~lt, ~ le~ ha di~tance t:he implemen~ ~an dev~ate ~r~ both a~ nd b~alow the levQl ~mplemsn~ pos~tion wi~h~ut e~cc~ed~ng ~h~ ~lt misalignm~nt ~n~le.
~ith th~ conven~ional ~ cture, the int~ eagate sh~t ~ ~ req~ p~rtially ~e~ause the ~ngine ~ra~ ha~1: and th~
tr~n~axle cente~line have ~en ~i:epara~ed by ~;ucb a r~ ively ~r~a~ distanae. Th~refore, utilization of onf~ or tran mi~ting power ~r~m the engine ou~put ~haft to ~h~
i~plement inpu~ ~haft wa~ i~praoticalO S~eci~ic:ally, ~ven ~f tbere w~re ~u~f icient c~learance between ~ slngle ~lt ~nd lbwer portion o~ ~he t~ar~xle hou2~ing to enable ~he ~lt to pass ~hereunder and to allo~r ~o~e vertical ~loa~ ce the ~listance ~eparating the en~ine arank~h~ft and the tr~n~a3c~e hou~ing wa~ rela~iv~ly great, t:he vertic~l floa~ an~le pro~rided 2~t the engine crar~c~haft ~ul~ey wa~ le~; in ~he vertic:al ~l~eation th~n ~h~ b~l~ mi~align~ent an~le due 'CO
interfer~nae between ~he hel~ and the botto~a po~ion o tlle tran~axl~ .
An additional problem en~oun~8r~1 wi~h ~aoll~entional e~sgine transaxle ~rranS~nea~t~ ~urin~ the d~a~elopm~ant o~ ~e p~ en~ inv~ntlon involve~ how you a~ble ~he e~gin~ and transaxl~ lnto a ~ while ~naink~lning an aa~epl~ le vehic:le Genter o~ gra~ity ~imul~:an~ou~ly Wi1:h zm a~ceptable cleara~ce bet~een ~he }~otto~ ~ the engine o~a~put ~haft ana ~he ground~
With tlae ~ngine and the qon~n~ional ~ranq~xle conf i~ d a~ a unit, th~ vehi~le c~ent~r of gravity ~a~: too hi~h f~or u~e in fron~ m~un~ mower-type ~ehic:le~3 ~n~ th~ corl~entiona~
hydros~ tran~xla ~r~v~ a~r~nge~ent wh~reby l:he ihydropump was c:onv~nti~nally driven 1~ t~e ~ngi~e ~:ranksh~f~ provid~l inade~uate ground cl~ranoe for the ~ngino c~ran~cgh~
With ~on~en~ional engine trana~axle c:onfîgw:~ation~, havit hydro~ta~ic trans~i~ion~:, sep~rate lu~ri. ::a~ing ~yst~m~ have be~en u~d t~ ~:epara~ly l~rica~ce tbe Qn~ine, the~ d~f~xe~ial 132~2 and ~o provide hy~lrau~ia ~luid iec~ he hydro~tat~
t:ransmi~isl10 If the hydrosta~ luid y~'cedn and the eng~ne lubrica~ing flu~d ~stem zllong wi~ h~ tr~n~axle ~ stem c~uld rcorlnected, a æimpl6~r, ~o~e ~erviceable un~t w<~ula s re~ultO
P.a~ordingly, l~re is 8 neRd ~or an i~nprov~ ~ nfs ~ran~axl~ ~om}:~inAtic~n whioh elimin~e~ the i2~r~edla'c~a ~h~t and th~ two pul~ey~:; wh~ch pro~rides adeq~a~ alear~zlnce 80 that ~ single Y~elt ~an be ~onnected direatly b~w~n the en~ine 10 output ~haft and the ~o~r de~ or othe~ ~orking i~plemen~
input l3h~f~; whic~2~ po~lti~n~ the engln~ rela~vely c~108e to ~h~ ~ransaxl~ center l~ne ~hereby d~area~lng the d~st~n~e ~rom ~he en~ine ou~.pu~ shaft to th~ Ap~ment input ~:ha~t while simult~nQou~;ly maintaining an a~cepta~l~ v~lc:la centsr ~f 15 ~ra~ whi~h s~h~ ns ~e en~n~ c~utput . h~t ~o ~hal:
ad~ua~e ground cl~r~nce i8 ~ain~ln~ rhi::h utiliz~ the engin~ crar~k~dhaft ~o drive t~e hydropump ~rom a locatlon ineide l:he e~glne; which ~31imin~te~ i~tex:P~r2na~ ~etw~n t*~e single V-belt ~nd the tran~aaxl~ hous~nç~; ~hl~h pro~ide~ ~or ~0 increased~ver~ic~l impl~ t ~le)at; whiah pro~ide~: ~or re~ua~d c~ n hoth ma~exi~l a~d assembly labo~; ~dhich ~pli~ie~ ~he ao~neat~on be~w~en the engine ou~puk S:ha~t and th~ ~ower d~qk or ot:her wc~rking implemerll~ wh~ch pro~rlde~ for a~rmon flU~d ~etwe~n the engin~ and a~ lea~:t one ot:}~e~ of ~h~ hydro~:tatia ~ ~r~nsmiQ~iorl, the ~ erenti~l, and,~or, ~he a~:le, O~L51~
The preg~n~ invention i5 an ~pro~e~ engirl~ ~rans~xle c:o~in~l~ion whic:h, amon~ o~h~ar ~a~u~e~, pr~vi~a~ ~or d~r~tly ~onnec:tinS~ th~ en~ e arar~ha f t and the in~pul~ t to an 30 input ~ha~ o~ a ~ ~ de~c or o~h~r workâAg i~npl~ with a ~ing~e v- bel~ ~e~n~ while Sill allowing ada~te ver1:i~al belt m~ nt Wit210U~ in~e~erenc~ with ~e t~a~a~le and for arranging ~hç~ omponent~ o~ ~ hy~roy~atiG t~ iorl~ engin~
and txansaxle in c:ombinati~n ~o ~h~ ~n acaep~ak~ rehiol~
35 ~:ent6~r o~ ~ity ana an acce~tal:~le ~:lea~ane~ bet~een t~
~ngine output ~haf~ ~rad ~he çlround ~re ~i~nul~anaously pro~ridl~d .
In ~he l?re~err~ad e~bc~ent o~ th~ en~ine/trarl~xl2 ~nit, a ~;ingle V-l~el~ conn6~:ts ~he e2lgin~ ou~pu~ ~h~t and S:~e ~32~8~2 imple~en~ lnput ~.ha~t and p~:s~es und~r the t:ran~xl~ wiS:~out in~er~erin~ w~th ~he ~r;~n~:axle ~hrough ~he en~ire ran~e o~
i:mple~Dent ~e~ 41 float. ~rhig d~e~:t conn13a~io~ bet~reen the en~ine output h~f~ ~n~ the impl~en~ lnput; ~haÆ~ i$ mad~
S pos~i~le ~y th~ disr-losed Con~i~atis~n o~ ~e Qng~ n~ ~d ~ransa~fle ~ombin~ on and by th~3 ~rra~gemerlt ln the tran~axle housing o~E ¢erta~ n oomponent p~ of ~e hy~rogt~la t:r~nsmi~:iorl 2~nd the txansaxle lnoluding ~ y~oD~oto~, a ~pee~l xedu~tion ç~a~ unit ~nd a di~e~ential unlt:.
0 In the ~re~erred ~mbo~ ent, a po~lon o~ th~ t~nsaxl~
hou~in~ utilize~ a~ an ~ntegral portion o~ ~h~ ~n~ine to c:omprise ~ t2nitiæed engine tran~xleO How~sre~, ~t ~ish~uld ~
note~ that the advant~ proYided ~y ~he preeent inv~ntion do n~ require that th~ engine and th~ ~rara~;~xl~ h~Ye a c:o~mon hc~u6ing only tlla~ the ~rar~ous ~omponer~t part~s ~e po~it~ oned ~o that th~ aavanta~es of the c~mbination ar~ acqo~pli hea wit~hout rsg~:td to t~he p~rtiaular ma~n2r in whic:h th~ valriou~:
Qomponents a~R ~e~n~le~ et~
Fo~ ~3X~aple ~ ~n important f~a'cur~ op t:he pre~:Q
o l~vent~on in~lude~ t~e relativ~a phy~ zl po~ lonin5~ of the ~ngin~ tc~ the transaxlQ and ~h~2ther ~he~ are ~srely operati~rely conne~ed ~o~e~er by ~onnec::tion means su~:h as bolt~, rivets, welded eta. or whethe~ par~ of the engine i~
ass~led intc~ a portion ~ the transaxle hou~;ing it~;elf is 2 ~ immat~arial .
An add~tional i~x~ant a~ t of th~ pr~ent $nvent:ion inalu~e~ the low~ring of the vehi~le's ~nt~r o~E g~aY~ty ~y poE:~tioning ~he engine ~rank¢th~t a~ ¢lo}ile to t~l2 aenter ~ine t:3f ~h~ axl~ a~ po~;sibl~ and by lo~erlng the en~in~a xelati~e to ~he axle`~3 c~nter lin~ while main~ining ad~ te ~ aarans:e be~wsen ~n~ engin2 outpu~ sha~t and ~h~ d. ~ icAll~, ade~t~ ou~pu~ sh~ ground ~ nc:e ~2a m~in~in~d by ny ~he hydropulRp~, ~whic:h i~; at~at:he~ tc th~3 e:~:eri~r of t;h~ engine ~y a gear mechani~ loc~tRd in~i~e th~ gine, ~ay . 5 the engin~ aa~ ~haft~
~n e~ren furthe~ ~;pect of ~ pre~;enl~ in~e~ion inalude the ut~ at~on of c:o;~mo~ u~ ~twee~ thQ hydrc~at~c ~n~axle, the r~aduc:~ion gear and ths~ di~erential ~ear o~ 'che trans~xle.

.~

~3~8.~2 A ~:tlll ~urther aspect o t}~ pxssent irl~et~ion inc2ludes~
the utlliza~ion of aommon f luid ~ lubr~ t~ the ¢ngix~ and as hydr~ul.~c ~lui~l ~or the hydro~ta~c txan~m~ 3 axle andlc~r a~ lu~iaation ~or the di~eren~al.
S Aacordingly, s:~ject~: o~ ~e pr~ ent 4n~r~t~on inclu~es to p~ an i~prc~ed work v~hicl~ havlng an en~ln~ ~r~n~:axl~
~rrange3~ent whi~ u~lizes a ~i~gl~ ~-bslt ko tr~n~er E~ower fxom the ençline to a w~rk impl~nt; to pro~ e an int~a~rnal tr~nqaxl~ ~o~ponent part~: arran~emen~ which ~ac~ e the 1~ ~irect ~ kaqe of ~h~3 ~n~ine c~utput ~ha~ wi~h the imp~ent i~lpUt ~ha~t ~ria a ~3ingl~ ~r belt; to pro~ida a s~ po~en~ partæ
~xangem~nt which all~w~ a aorn~on ~ id for en~ine lubrica~ion, hy~auli~ luid fox the hydxo6tati~ ~r~ mi~ion, and/or ~ubric~a~ing fluid for lth~ ~p~a~d raduc:tion g~r, and ~h~
di~rer~n~i~l or ~h~ tran~axle ur~it; ~ p~o~i~le an englne ~rar~xle ac~ ination :3imult~neou~ly ha~ring~ a low ce~ o~
~ra~tity ana ad~quate clearanc~ between 'r:he ~rlgine output sh~ f t and ~h~ ground; and to provlde a p~eferred wniti~e~l en~ne trans~xle ~oml~ination h~ving a co~n~n part;ial h~ ng D~e~b~r for bc~h the ~n~ine and the tran~axl~.
Other ob~e~t~ and advant~ o~ the inv~nti4n ~ill be apparent fro~n the ~llowinq dee:crip~ion, the at:c:ompatly~ng dr ~wing~ and ~he ~ppe~nded cl~im~

FIG. i i~ ~ si~e view of a ~ron~ ~ount mo~
inac)rp~ating the conLbin~ion engine t:r;~n~xle of ~ pre~;en~
inventior~:
FIG. 2 is a gchematic per~:pective ~rie~ ~i~l~ partia~ ¢u~
away p~rtions illustr~tin~ a cc~n~ntional engine tran~xle combina~ion ms:?unted on a ~ug~y; -MG. 3 is a sc:~em~t~c: perspeclti~ ~iew w~th cut away po~tions~ u~3~ra~ g t~e utilizatiorl o~ ~he pr~s~n~ in-~ntion a wouls~ ~ moun~ed on ~he bu~gy of FIG ., ~ S
FIG . 4 i-~ a ~ide v~esr with por~io~ clut aw~ O~e kh~
engine o~ on~ ~mbodi~nent o~ ~he en~ne ~ransaxl~ c:ombirl~$~on o~ ~he p~e~ t inv~3n~10n FIG. S i ~ plan ~i~ the ~n~na wi~ por~ons of the ~xan~axle hou ing r~moved showing the in~ernal arr~n~e~ent~ of t~e ~a~ou~ o~ponl3n~;

1~208~2 :F`IG . ~ is a ~ew taken alon~ 6---6 C~X FIt: . 4; and FIG, 7 i~ ~h e~la~ged ~riew o~ rarls~xle co~$nat1on illu3txzs~1 in ~t;. S~

s As æhc~n in FIGS" 1 ~ 3, ~he lpxeferred ~ met~ the pr~n~ i3wen~o~a can 2~ utili~ed on ~ ~ron~ ;~ount :~c)~e~ a~
~llustrated in FIG. 1 or on a rear ~ovement ~ r ~
illu~trated in ~ 3. ~or pu~p~e~ o~ di~c:u~io~ ~er~ain, ~he ~e nu~ 6 will e ut~lized ~or the ~ r parts o~ ea¢h vex~ n illu~rated ~n ~IGS. 1 and 3. ~:a~ fi~e ~llu~tr~te~
a ~ower 50, ha~ing ~n operator`~: s~ ion ~2 indudin~ a~
oX~er~tor'~ ~eat S4 ana a ~teerins~ whef~:l 5~, A ;~lowllar de~ 58 i~ oper~ aly ~onn~ t~d ~o each Yeh~ le by ~ paiX~ of conneation ~erPber~ 60 ~or ~winging ~s~ement al~ou~; a ~r~n~Ver~e ax~ 62. The preferred embodi~ of the in~ntlon inalude~
an ~nç~in~tt:r~n~axle ao~ination 90 (FIt;. 4) WhiCh i~s ass~bled into a unit ha~in~ a~ lea~t a cc~on part~al hous;in~ mem~r, k)Ut ~hiC:h a~n utilize aonnec:ted se~ra~e hou~;ing m~3~rs ~or the e~gine ~nd the tr~nsaxle . ~e ~hc~wn, in FIGS ~ 1 and 3 -~0 the ~xle of t2ae mower 5a îs utili~4sd to po~re~ or drl~ the wheel~3 6~ r~ore, ~h~ ~n~int~ 70 and tran23zlxl~ 7~ are prefer2bly îocat~d undernea~h the oper~tor`t3 ot~ti~n 52.
In order for the Dlower de~ S8 to ~e driven ~y a ~lngle V-belt 74 connected with ~he e~ine crankshaf~ 76, c21~aranc~3 ~ean~: 80 ~ust }~ pro~id~d for allowillg the V-belt 74 ~o pas~
~ro~ ~he engin6~ crank~h~t 7~ and underneath the transa~cle hou~ g ~ ~o the input shaft ~ of the ~w~r de~c S8 (~e~
~. 3). This c:learanae ~o mu~t ~ ~uf~i~len~ ts3 all~w ~}~e mower dsc:k 58 to hav~ adequ~t~ vertical float ~ that tha transaxle ~ou~ing 82 ~oe~ not ~ontac:l~ or opor~tio~lly inlk~3r~ a W~th ~e ~ }~31t 74 d~ing t31e 1~ran~:fer o~ Eu3wer ~Erox~
~he ~ngina cra~shaft 7~ to ~he mower i~pu~ ha~t 86.
To acc:ompliæh thi~, a~ ~hown i~ ~G~ . 3 - 6 ~ ~e er~gin~l~r~n~axl~ c~in~t~on ~0 o~ the pr~sen~; in~ntio~
35 asse~lea to~ether with t}le engine ~r~ 76 ~ing verticE~l and positione~ clo~a to ~he axle ~:en~er li~le 92 ~o that the pull~y 94 (FIGS~ 3 aAd 4~ on the en~in~ cran~c~hz~ 76 i~ as ~210~:e to ~he tran~axl~ hous~ing 82 a~ bl0. ~I!hi8 ~rr~r~ge~n1; m~nimize& po~ible in~rf~ena~ we~n l~lle ~Qlt .,...~

13208~
~4 and the lower portion 96 o~ th~ tr~n~axle hou~in~ 82 a~ the ~ower ~ f loats over lme~v~2 terra~n ..
To provide ~ low ~ehi~le center o~ y ~h~ till ~aint~inlng ;~daquate c: learanc~ betw~n ~e pulley 94 and t:he 5 ground ~ ee FI~ ~), the engin~ 70 is~ co3~n~G1;ed t:o ~e transaxl~ ~ z~ los~ to the ~ound 98 ac pr~a~i~;2~1..
In or~ler ~o pxovide adegua~e clear;ar~ae or the ~ elt 74 undex tl~e tr;~n axle housing ~ ren~ial un~t 100 is po i~ion~d lnsi~e ar~d to one ~;id~a of ~ the ~r~nsaxle h~U~3~ ng 82 10 at a location pre~erably pxoxi~ate ~he riç~h~ ront whe~
t~ ~ow~r vehicle 50. In vehi~:le~ ~uipped w~h hya~oetatic trans~i~ion~ ~see l?I~A S) ~ the h~d~o~o~o~ 104 ~ 0 prefera1~ly operatively pc~ ione~ ~n~:~de th~ 'cran~axle Iho~in~
~2 ~o on~ le ~n~l ~t a location proxi~ate the~ le~ ~ron~
15 wheel of the v~his 1~3o A sp~e~ re~uc:Sion gear 10~ i~
op~rat~vely pos~ tioned in~ide She t~n~:axle hou~ing 82 proxi~a~e the hydro~otor 104. The ~p~c~ic loe~ons o~ ~he dif~er~nti~l ~00, the l~y~ro~otor 104 ~nd ~ s;pe~ edu~tion gear 10~ ~an ~e varied within 'che ~ra3~axle ho~ ng ~o aa~ordin~ to ~pecific resluiremen~s~ it ~ein~ under6to~d that oth~3~ arrange~nen~ o~ ~he variou~; sub-co~pc~nent part~ ~an be pl~e~ ~n ot~er pos~tio~s than ~c~e illuætratoa an~ ~till ~e within the ~cope of th~ prc~n~ in~verlt:~on.
In partiaular, on~ c:ritiaal a~peo~ o~ ~he pre~an~
25 inv~n~i~n 1~; ~he amoun~ o~ c:learanae ~equir~d ~y ~he ~ 74 wh~ch corm~cts the ~n~ e aran~c~;haft 76 ~i~ ~he l~pu~ m~ns c~n ~h~ mow~r de ;:k SZ ~ In FIGS ~ 1 ~nd 3 I the ~o~r d~ k 58 is ~hown ~pera~ing on a level ~ aae~ me Y~Blt 74 ~no~ d ~etwe~n th~ ~n~ine ~ran~sha~ 76 and ~he ~os7er dea~c lnpu~
~o shaft 86 (~ee FIG. 3) 1~ ~:hown ~n ~t~ nor~al leve~ oper~ting po~:ition~ However, wh~n the ~owe~ aeck 58 i~ cau~ed to ~o~e ei'cher alwv~ or ~low the le~l ~sitiGn ~hown, ~uc~ ~ ~h~n 6~nc:0un~ring r~u~ll or uneven t~rrain, '~ mo~r dl~c:X 58 and the belt 74 conne~a t~exe~o deflec~ her up~ardly or 3S downwardly from ~he lev~l po~tic~n of th~ ~n~ne pull~y ~4.
Sin~ o~ anu~a~turer~ r~ao~men~ onïy ~ 5 ~elt misalignmer~t angle ~rom th~ leva~l pc~ ion, i. e, a~ tho bel~
exit the pulley~ ~he ~xe~t~r ~he ~ tia~ tan~ w~n the pulley g4 aarri~d ~y ~h~ engi~e ~ar;~h~f~ 7~ and th~
.

.~

132~ 2 i~plem~nt input ~haft 86, the greilter th~ belt de~le~ion.
Thu~ he~e iG a re~ui~ment 'cAat th~re b62 ad~cauate a~ea~anae 80 ~a~ween th~ ~-b~lt 74 ~nd the lower por~ion 96 o~ ~h~
transaxl~ h~u~ing 82 to pr~v~nt th~ tr~n~axle h~ue:ln~ 82 ~rom 5 interer~ng wit2~ ~ b~lt operation.. This clear~na~ 80 i~:
o~ain~d by the arrang~en~ of t:~e varlou~; ~ub-compor;an~
within ~he tranl2axl~ hou~ing ~2 2~nd th~ tran~xle con~suration wh~h a~sco~ ate~ the V~ de~le¢~onD
Anot~er con~ ration ~in the locatiorl v~ th~ ~riou6 ~3ub-10 componen'c~ in the tr~n~a~cle hou~:ing 82 1~ tha ~Eluld f~s~w ~romthe ~n~in~ ~3~np llo ~e~ FIG;~. 5 ana S~ to t~e hydropu~np 112, ~he hy~lromo~or 104 ~nd baak ~o the hydropump 112. I.eakage~
from ~hi~ fluid flow system ~s. preerably utili~ t~a lubricate the ~peed redu~~tion gear 108 ahd/or the d~f~erential 15 100 ~ Ag~er lubri~:a~on o~E ~he spee~ ~e~uation ge~r uni~ ~Os and/csr ~he diffe~n~i~l unil: 100 " t~e flui~ ~æ r~urne~ to th~
en~ln~ ;eluid ~ump 110~
In ord~ to pro~ide ~7r ~ akx:~e~ the ~ollowi~g component parts combination wa~ d~t~in~3d ~ ~ing one o~ a 20 plurali~y o~ possible combin~ation~ whiLah ~ight ~e ~ati~faa~ory. P.~ ~hown in ~he prefer;red e~odiD~n~ FIG~ 1 and 3 - ~, the ~ref~red ~ngine tranæaxle Gombi3l~ion ~0 inc:lude~
a ~ubular l~ransaxl~ hou~:in~ ~2 op~ively conn~ac:t~ to the ~ngine 70. ~h~ an~xle hou~ q 8a pr~fera~ly inaluae~ at 2~ lea~ a po~l:ion ~3 which pa:~tiall~ enc:a~:els 1;h~ e~inq~ 70 ~see ~IG. 4)., A~ ~hc~wn in ~IG. 5, ~he hydx~omotor 104 ~g po~ ioned w~thill ~e t~ansaxle l~ousing 82 along wi~A the ~p~ed redllc~ion ~mit 108, the di~ferl3ntial unit 10~ ~nd th~la axl~ 10~ llts~
The hyarauli~ mot:or ~04 ~nolu~e~ a hollow ~xle ¢axri~er ~0 114 which i~; rota~a~ly suE~po~k~d ~ lts en~: by ~all ~ar~ngs 118 and needle beari~gg 12~. An ec:~:entria c~ix¢ular sl~av~ 12?
i8 *ox~ned at one en~ of the carri~ 114. P.L di~X~ ped c:ylinder l~lo~ 122 ie2 ~ ly ~ ge~ with ~;pline~ ~orlAe~ in t:he oute~ periphery o~ the carrier 1140 A plural~y o~
35 p~;ton~ 4 ~re equ~angularly proYid~ c:on~aal &~ a~
the c:yl~nt~er ~ A t~u~t plate lZ6 ~s ~r~vided ~Eor reaeiving thru~ fro~ the pi~;ton~: 124 which A:~e rota~ably ~:upported wi~in th~ ~xia~ hou~s~ng 82, e~o ~hat the th~u~
plate 12~ ~ay x~ate ~n a ~orward d~rec:tion or ~ rever~

~32~8~2 direation. Th~3 ~ylinder hlock 122 ~ u:3ed ~ a bxa~
~here:Eore, a l~axld l~r~ke 1~ pro~i~e~ a~roun~ ~h~ aylin~er blo~k 122 to ~ re a~ the bra~c~ m~ch~ni~
In or~er ~o supply power ~or operating th~ hydr~ulia motor 104, a variable hydraulic pump 11~ ~c operatively positione~ on t:h~ eng~ne 70 ~n~ riv~n ~y a 2am gh~t ~chani~ 130 (8ee ~IG~ 6~ which i oE~atiYely po2;~t~o~ed in3ide ~he engine and operatively cos~nec~Q~ ~ith t:he ~k h ft 76 craI ~ a ~ particular arrangement i importan~ to ~:he overall ~uoqes~: of the aom~inat~cn. Spec:i~iq~ b~ po~ioning t~e h~drop~mp 112 on the exterior of th~ eng~ne 70 ~nd by driving it by ~ cam sh~ ge~ ~y~ po~itlone~ inside ~h~ engin~, the engin2 c~uld ~ c~nne~t~d ~o the tr~n~axle 72 at 2~
po~ît~on relatively alo~r to the yroun~ t;h~n k~f~a. qihis relatively lower pos~tioning pro~ es ~or a veh~ale wit~ ~
lowe~ centex of g~rity, the2~eby i~proving st~bili~y ~nd al~o ~edu~ing the le~h o~ the c~raxilc~ha~t 7~ ~hiçh ext~ om ~he b~ engin~ 70~
~hrough reduain~ the ho~i~ontal di~nc~ en the engin~ crankshaft 76 and the tran~axl~ h~ 82, th~
vex~iaal dis~anae ~hrough whic~h t:;~e b~lt 74 swing~ ~neath the low~r pc~ on g~ of ~;he tr~nsaxl~3 ~ou~ 82 w;~s ~edu~:~dlr thereby ~ncr~a~ing the distance the ~xont mounte~ i~ple~enlt a~uld ~o~e abc~re ~ :tevel po~$t~on rel~ltiv2 ts~ en~ina pulley ~4 without h~vin~ ~he 1QW~ portion o~ r~n~axle ho~ing 82 inter~r~ wit;h or c:ont~at the ~elt 74,.
A~ æhown in the plan ~ ew of FIG O ~, th~ hydropu~p 11~ iB
pxefe~a~ly ope~tively qonnecte~ to the l~t lowex :~de por~ion of l:h6a ~ngin~ 70 o~ ~ne pre~re~ uniti~d ~ ine-~ran~axle combina~lon g5. A~ ~hown in FIG~ wo ~ d l~ne~ ~ ~0, 16~ ~r~ utiliz~l in ~luid c~om~u~C~2~ion bet~reen ~h~
hydropump 112 and the hydro~otor ~04, one li~e ~or flow in ~ach dire~:~ioh thea:eb~t~en, d~ n~ing upon ~he~her ~h~
vehic~le ~s operating ~n the re~er~e or th~ ~ rc31 ~rection.
Further ~e~ails: of t~e unitiz~ eng~ n~ onfi~ura~ion rela~ed ~o t;he ~re~ent invention ~an ~e ~ouna in U ~ S ., Paten'c 5,0~7,~33, ~igl~ed ~o the ~igne~ of the pr&~nt invention 13208~2 A~ o~m ~in F~ , a mechani~3m ~or ~r~ns~errln~ p~w~r dirQctly ~rom the engin~ aranlcsha~ 76 to the input 23ha~t ~13 o~ ~he hydropump 1~ trated. q~h~ hydropu14p 1~2 i~
d~x~tly connecte~ to the ~3ngine 70 ~ouyh t:he a~Q ~h~t 130 whiah ha~; ~ c~m gear 170 opera~ ly connected th~xeto. ~rhe ~am ~:haft ~30 is po itioned intermed~ate an~ para~lal to th~
engine ~r~ks~a~ 7~ and th~ hydrof?~t~tic pump inpu~ ~h~f~
113. The a~ gear ~70 ~n~lude~ ~w~ ~eparat~ portions 172, 174 each having t:~eth 176, 178. one o~ the cam gear po~tiong 172 ~0 inter~eB~es ~ith ma~h~ng t:ee~h 1~0 on the eng~ne c~a~c~haft 76 ~n~ o~her ca~ gear po~on 174 int~r~ae~e$ b-ith ~natin~
te~th ~82 on a gear 184 G~ d ~y t~e hyd~o~t~t~c pump input sha~t 113. Th~ shaf~ olE t21~ aam gear ~nech~ni~m 130 in~lude She cam 131 and ~he ca~ srea~c ~70, bot2~ of ~hiah ~r~ po~it~onea in~;id~ ~he engine~
rhe drivins~ or powering of 1:he hy~rost~tlc pu~p 112 by tbe ~ gea~ m~acshani~n 13~, in~3ide t:he ençlin~ 73, pro~ideæ ~or in~r~asin~ the fli~tance ~tween th~ enél of eng~ne ~rari~c.ha~t 7~ ~e hydro~ati~ pt~mp 112 and tho en~ine ar~nkoh~t 7~ are 2 o othex~i~3e ~onventionally c~ ru~tea .
Thîs partiaulax ~ructure for pow~ering th~ hy~rostat~ ~
pump ~2 whic:h provid~æ ~or ~c~e engine ~o ~ po~ Pne~ clo~:er r~lati~r~ t~ t~e ground al~o redu~ Y~ c~nt~r ~ravi~y and theroby lncrea~eæ the v~ le'~ ~tab~lity. .
T~* ~peed r~duction uni~ 108 i~ a pl~n~tary ql~aar red~action type ~ is well known in t~e axt. Pl~nekar5~ piniorls 13~ ar~ ~eshed with an~ ~ri~ n ~ an out~r p~arîphery o thQ
c:i~rcular ~;leeve p~cion 127 o~ the carrier 114 1:hrou~h ~11 ~aringç~ and ~ inner ~e~th o~ a r~n~ ge~ 4 are ~lx~d 3 0 to th~ axle ~c~u~ 2 and are Dle~hea wi lth the oute~ ~Qth 13 3 o~ the p~ane~y pinions 132. S~ e~ are ~or~ n t~ r p~ipllery o~ She bos~ por~io~ oi~ the pl~ne~ry pln~on~ 132.
A~ ~ho~n, it i~ pre~err~d th~t the planetary ~i~ions 13a ha~e one 1~8 ~ooth th~n ~he ring~ g~ar 134.
~he di~f~rent~ial uni~ 100 in~zlu~e~ a ~lsul~r s~ erentia ~ear box 136 whic~ is i~el~ rot~ bly ~uppor~:~d ~ e ~le hous~ ng B2 by b~ earin~s ~3~ 0 Op~rati~ly aonnec'c~d ~co th~ di~erential ge~r ~x 13~ n endl ~h~é 140 ~uppc-r~
me~r. In ~he preferrecl e3~0d~hent, thi~ ~r ~40 ~320~52 forxR~d af~ an in~e~ral portlo~ o~ tha gear box 1~6. A pair o~
æmall l:Nav~l gear~ 142 ~re rotat~bly pivote~l in tl~e inn~r peripher~l por~ion o~ the dl~erential geilr box 136" A pair oP ~a~ bevel g~r~3 144 en~e the pair o~ ll bevel ~ar~;
5 142 ~nd ~re rot~tably ~pported b~ ~e inner per~p~e:rie~ o~
th~ a~f~rential gear box 13~ and the en~ ~ha~t 8upport mem~er 140. 5pl~ne~3 146 ar~ ~ormed in ~n end portion of 1:hç~ ~nd s~f~ ~support ~ r 140~ ~me ~3plinQ~ 135 c~ planet~ry pinion 132 ar~ opexat~vely co~nec~e~ ~o ~h~ spl~ne 146 o~ t:he 0 s~ha~t ~r t~e. axial hollo~r ~pllne lS0 .
TAe ax~e ~nit al:3o inalu~e~ a l~ng a~la Dle~bex ~5~ and 8hort axle ~emb~3r 1S4. ~he l~ng axl~ ~ember 152 ~
op~rat~rely ~onnect~3d a~ one end to an inner periE~hery of one o~ ~he large ~evel ge~r~; 144 ~nd pro~f3a~ at ~he other end ~rom one side of th~ ax~ hou~:ing 8~ pas~ing throuslh t~
holls~w ap~rt~lre~ o~ the carriex 114 2md . he pline ~50~ The o~her ~nd of ~h~ lon~ z~x~a 1~2 is rota~a~ly uppor~d in the ~xle hou~ing 82 by ~he needle ~earings 120 and the ball ]bearin~3 15~, The short axle 154 is ¢onnç~c:t~d ~o one ~nd o~
~0 the inner periphe;rsr o~ ~he o~er l;~ge bevel g~ar 194 tl~r~ugh s~ n~ ; rota~a~ly ~;upport~d at the othl3r en~l on ~:he ot~r siCle o~ ~he axle hou~ g 82 1~ ball beari3lg~ 14~ and pro~al~
to ~he out~;~de. The drive ~he~ls 64 ~re fixcad to 1:~e projecting porl~ion~ o~ ~he lc~ng and ~ho~c~ axle~ 1~2 ~nd 154 2 5 re~pec~ti~ely .
In the preferred ~m~c!li~enl~ to provide: a~equaS~ belt c:lear~rlc~ ~0 und~r the transaxl~ hou ing ~2, ~ ai~ r 0~
the ~rane~a~le hou~inS~ 82 is re~u~d a~3 much a: po~:sil~le . The ~e:du~ed c~n~;ral port~ion doe~2 no~ int~rfe~e Wi~ he ~evolution 30 of the ~nd ps~r~ion on ~e planet ary pinio~ 132 o~ ~h~ ~pline ~ointE; 135 ~:inc~ th~y ar~ lwated to one end ~ the ~ransaxle hou~irg 82 . A~ th~ ti~e, a~ sho~rn in P~S . 3 and 4, the axle housing center line x--x ~; loca~ea ~o~e a horizontal llne ~ough the ~en~erline oi~ ;IX12 y--y. ~hu~, ~;hQ al~arance 35 or spa~e 80 1~: formed w~ h p~ovl~le~ adequate l:learanoQ ~or the V belt 74 which ~onrle¢~ the engin~a 70 with th~ ~o~king imple~en1: ~8 to oper~e and ~till pro~idæ ade~aua~e ~aple~nent ~ertical ~loat.

A

1~2~2 ;~ring th~ opex~on of the ~y~r~ulic motc)r 104, the wor~cing ~lui~ w}~ h l~ak; ~herefro~, ~lows ~rough the tran~axl~ houcing 82 ~n~o ~h~ Ghamber c:ontalnlng the di~erent~al ~nit 10~, and i~ returned ~ to th~ vari~bl~
S hydrau~ia pump 11~ through a return pipe lgo. In th~3 pref~rr~d embodi~ent" the f~id is; r~turned to ~he engin~ a~mp 110 through in~ern~ a~s ~not shown~.. The fl~w ~2~t~ o~ th2 leakage of th~ hy~aulic: motor 104 to ~h~ dif~eren1;ial unit ïOO i:~ inc:rea~ed ~lue to the fluid diameter of ~e p~ag~, lo i ~ e. the transa~le ~ou~:ing ~:ro~ ec:t~on~ ~rc~l~ t:hat point over to t~ di~ere~tial 100 be~ng re~luoed. ~rh~a working ~luid 1 cooled by c:ool~r2g fin~ ~no~ ~hown) formed aro~ ~h~ aen~r~l port~on ~x the ~luicl p~ 3e8 Shrough ~he deoreas3ed di~etlar pa~. ~ge.
In op~xa~i~n, wor~cing flu~d i~ uppl~ed to th~ hya~aulic~
motor 104 by the va~i~b~ hydraul~c: pu~p 1~2 which is~ dri~en the er~gin~ cr~ haft 7~. Ro1~ion o~ the c:ylind~r bloc~c 122 causes 1the cirau~ar sleeve ~27 o~ ~he c~arri~r :L~4 to ao~c:entric~ly rotate a~ ~e ~ame rs~ational ~:pe~ad~
Tl~er~fore, the plan~ary p~ni~n~: 132 ar~ meched ar~d revolve - with the rin~ gear 134 so ~ha~ th~ planet~y pinion~ 132 are rota~e~ a~ut ~heir o~m a~e~ in the rever~:e ~lireu~tlon to the r~volution pr~duced by ~e hydro~o~or 3lO4n ~rhe rot~tlonal motion Df~ 'ch~ planetary pin~ons 132 i8 t~ans~ te~i ~o ~
~plin~ 150 which in t~arn dr~ves the ai~ ~er~an~iAl gear box 13~, which in turn ari~res the ~;mal~ be~el gear~ 142 to d~e th~
large ~el gears ~4A and t~e sha~t 15~ whlch i8 æpl~rled to ~he ge~r~ 144 a ~e crank ~ha~t 76 c:au:s~s ~ r~n~i al ~ear box ~36 ~o rotate and ~ &aus~3 th~ lor~s~ and short axle~ 15~ an~l 154 ~o rotata th~ough th~ en~ag6~ 6~all and large k~e~ ears 14~, 14~, thu~, rotatin~ ~ot:h the drivi~g wheel~; 64. With the in~lusion o~ t~e ~lif~eren~al unl~ 100, when ~he ~rehiel~ is ad~ranced ~ htly, t~e dri~in~ wheel~ 64 are rotated th~ ame rc~tational p~eds, but when t~e ~rehi~le i~ a~an;:ed allong ~ c~rved path, ~e ~ri~ wh~3el os~
ou~Eide o~ e s~urve pat21 i~; ro~ d at a hiçlh~r ~;peed tha2 the other d:ri~ç~ whee~ on ~he in~3id~ o~ the aurve p~th.
on ~h~ o~her han<l, th~ cranlc~h~t ~ the eng$n~ ?0 1 opera~i~ely po~ ioned to drive the isA~ t ~nput ~ ft ~32~8~2 through the belt p~lley. ~rhe V-belt 74 ~nd the bel~ pull~y 86 are op~3ratively ~o~r~ected tc~ work~ng i~ple~en~ tb~ou~ the rance or ~pac:e BO ~xea~d b~r tha ~ele~;l~ pO3~ tioning 0:~
~he tran~xle c:ompone~ h~&, ~ven lf~ th~ ~Eron~ ~oun~e~
5 implaJaenl: i~; move~ ~;ic~lly ~n r~p~nE:e to 1~ Cl~;
txa~r3i;~ng une~n ground whic:h may hav~ d ~ h, ~h~
~pace and th~ tranE:axl~ ~hrou~ which the ~ pa~6~se: i~ o a u~ ien~ width And heigh~ 80 tha~ the ~ c wll~ nol~
~nt~rfere with ~he botto~ ~rfa~:~ o~ ~he t~ar~saxl~a h~Uglin-;Jr ~ith ~is~ ~onstruotion, there i: Jlo n~ or the conv~ntional int~rmedia~e shaPt ~nd lthe u~e o t:wo ~l~s~, one ~ro~ the ex~gin~ to th~ int;ermediate sha~t and the other f~
inter~ned~a~e shaf~ to th~ work~n~ i~pl~nt:~ ~e re~:ult is ~ignif~can~ly ~re~ter vertic~ loAt, dec~aeed ~ erl~l 15 manu~acture and ~Rm~ly ao~:t arld a lowex Yehi~le c~ent~ o~
gravity while mai~t~ining adegu~t~ g~ound cl~ar2~nae for the engine output ~2~aft 7 6 .
Wh~lq ~he ~ethod a21~ operat;ion herein aeScri~ed cotls~i~ute pre~err~d e~bod~nen~s o~ the in~en~on, ~t i~ to 20 unde~stood that th~ i~vention i~; no~ li~l~ed to th~ p~e~
method an~ operation, ~nd the change6 may b~ ~de t:l~erein with~t depar~ing ~rom the ~ $ ~h~ inYent::~orl ~bic~
~e$ir~ed ~n the appen~led clai~s~.

~4

Claims (18)

1. A work vehicle having wheels comprising:
an engine having an output shaft;
a transaxle for transmitting power from said engine to said wheels, said transaxle having an elongated housing interconnected with the engine, the housing including first and second spaced apart portions having a greater cross section than a third portion therebetween;
speed reduction means carried in the first portion of said housing;
differential means carried in the second portion of said housing;
belt means operatively connectable with said output shaft of the engine and an implement means adapted for vertical float relative to the vehicle and having drive means located on the side of the transaxle opposite to said engine, for transmitting power from said engine to said implement means, said belt means when connected, passing by the third portion of the housing whereby the transaxle housing does not operationally interfere with said belt means as the implement means vertically floats.

2. The work vehicle of claim 1 wherein said belt means comprises:
first pulley means operatively connected to said engine output shaft;
second pulley means operatively connected to said implement means; and a single elastomeric belt operatively positioned in each of said pulley means so that the rotation of said output shaft rotates said first pulley means thereby rotating said second pulley means for transferring power to said implement.

3. The work vehicle of claim 1 wherein a hydrostatic pump is operatively connected to said engine and a hydrostatic motor is operatively positioned in the first portion of said transaxle housing, said pump being attached to said engine.

4. The work vehicle of claim 3 further comprising:
a cam means operatively positioned inside said engine for transmitting power from said engine output shaft to said hydrostatic pump.

5. The work vehicle of claim 4 wherein said cam means further comprises:
a cam shaft having teeth means operatively formed thereon; and a cam gear, operatively connected to said cam shaft, said cam gear having an upper and a lower portion each having teeth means for interacting with said engine output shaft and said hydrostatic pump.

6. The work vehicle of claim 5 wherein said upper portion of said cam gear interacts with said engine shaft and said lower portion of said cam gear interacts with an input shaft of said hydrostatic pump so that power is transmitted from said engine output shaft to said hydrostatic pump input shaft.

7. A unitized transaxle for powering the wheels of a work vehicle having an engine with a substantially vertical output shaft and hydraulic pump means powered by the engine, when belt means is used to operatively connect the drive means of a belt driven implement adapted for vertical float with the output shaft of the engine, the improvement comprising;
a transaxle including an elongated housing operatively interconnected with said engine and located where it would be between the engine and drive means of said implement, said housing including first and second spaced apart portions having greater cross sections than a third portion therebetween;
speed reduction means carried in the first portion;
hydraulic motor means carried in the first portion and operatively connected to the said speed reduction means;
differential means carried in the second portion of said housing; and tubular drive means extending between said speed reduction means and the differential means and passing through said third portion of the housing.

8. The unitized transaxle of claim 7 wherein said housing further comprises:

a separate engine housing and a separate transaxle housing, said separate housings being operatively connected by bolt means to form a unitized combination.

9. A wheeled vehicle comprising:
an engine having an output shaft;
an elongated transaxle housing operatively positioned close to said engine, said housing including first and second spaced apart portions having a greater cross section than a third portion therebetween;
speed reduction means carried in the first portion;
differential means carried in the second portion;
power transmission means extendable from the output shaft, adjacent to the third portion of said transaxle housing to be operatively connectable to the drive means of an implement which can be attached to said vehicle with its drive means spaced from the transaxle housing and located at the side of the transaxle housing opposite to said engine.

10. The invention defined in claim 9 wherein the housing means carries a first wheel axle in its first portion, a second wheel axle in its second portion with tubular drive means extending from and operatively interconnecting the speed reduction means with the differential means to drive said axles.

11. The invention defined in claim 9 wherein the engine output shaft is substantially vertical and the power transmission means is a V-belt interconnecting the output shaft with the implement drive means, said belt passing beneath the transaxle housing.

12. A work vehicle having drive wheels comprising:
an engine having a crankshaft with gear teeth means operatively connected thereto;
a transaxle having a housing with first and second spaced apart end portions, said transaxle operatively interconnected with said engine to form a unit for transmitting power from said engine to said wheels;
a hydrostatic pump operatively attached to said engine, said pump having an input shaft with gear teeth means;
a hydrostatic motor operatively positioned in the first portion of said transaxle housing;

an implement capable of vertical float relative to the vehicle, said implement being operatively connected to said vehicle and being located on the side of said transaxle opposite of said engine;
belt means operatively interconnecting said engine and said implement for transmitting power from said engine to said implement;
clearance means operatively formed in said transaxle, for allowing said belt means to pass by said transaxle so that said transaxle housing does not operationally interfere with said belt means before said belt means reaches a maximum vertical float;
cam means operatively positioned inside said engine for transmitting power from said engine crankshaft to said hydrostatic pump;
said cam means including a cam shaft having teeth means operatively formed thereon, a cam gear operatively connected with said cam shaft, said cam gear having an upper and a lower portion each having teeth means for interacting with said crankshaft gear teeth means and said hydrostatic pump input shaft gear teeth means;
one portion of said cam gear interacting with the crankshaft and the other portion of said cam gear interacting with said hydrostatic pump input shaft so that power is transmitted from said engine crankshaft to said hydrostatic pump input shaft.

13. An engine transaxle combination for powering a work vehicle having an implement capable of vertical float relative to the vehicle attachable thereto, said combination comprising:
an engine having a crankshaft with gear teeth means operatively connected thereto;
a transaxle including an elongated housing means operatively interconnected with said engine to form at least a partially unitized assembly, said housing means having spaced apart ends;
a hydrostatic motor operatively positioned in said transaxle housing means relatively closer to one end thereof;

a speed reduction unit operatively positioned in said transaxle housing means relatively close to said hydrostatic motor;
a differential unit operatively positioned in said transaxle housing means relatively closer to the other end thereof so that a narrow section is formed in said housing means between the differential unit and said hydrostatic motor and said speed reduction unit;
a hydrostatic pump having an input shaft operatively connected to said engine, said shaft having gear teeth means;
means for providing fluid between said hydrostatic pump and said hydrostatic motor; and cam means operatively positioned inside said engine for transmitting power from said engine crankshaft to said hydrostatic pump, said cam means including a cam shaft having gear means operatively connected thereto, said gear means having an upper and a lower portion, said portions having teeth means for interaction with said crankshaft gear teeth means and said hydrostatic pump input shaft teeth means, one portion of said cam gear means interacting with said crankshaft and the other portion of said cam gear means interacting with said hydrostatic pump input shaft so that power is transmitted from said engine crankshaft to said hydrostatic pump input shaft.

14. The combination including a wheeled vehicle, adapted to support a work implement capable of vertical float relative to the vehicle, and having drive means;
an engine carried on the vehicle and having an output shaft;
an elongated transaxle housing carried by the vehicle and operatively positioned between the engine and the implement, said transaxle housing including first and second spaced apart portions having a greater cross section than a third portion therebetween;
axle means carried within the transaxle housing and operatively coupled to the vehicle wheels;
power transmission means coupled with and extending from the output shaft of the engine, between the first and second portions, adjacent to the third portion of the transaxle housing, and coupled to the drive means of the implement for drivingly powering the implement as it encounters vertical float relative to said vehicle.

15. The invention as defined in claim 14 wherein speed reduction means is carried in the first portion and differential means is carried in the second portion of said transaxle.

16. The invention defined in claim 15 wherein hydraulic motor means is further carried in the first portion and operatively connected to the speed reduction means.

17. The invention defined in claim 15 wherein tubular drive means extends between the speed reduction means and the differential means, said tubular drive means passing through the third portion of the housing.

18. The invention as defined in claims 15, 16 or 17 wherein the power transmission means includes a V-belt extending between the engine shaft and implement.