CA1281053C - Tractor - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
The wheel suspension of a tractor includes a transverse axle (12) disposed centrally of the frame of the tractor. Each end of the axle (12) carries two arms (13, 13, 14, 14) one for each wheel (15) at the respective side of the tractor.
The arms are independently pivotal about the axis of the axle (12). Each arm (13, 14) is provided with a hydraulic cylinder (16) for selectively raising or lowering the associated wheel. The invention provides a simple mechanism for maintaining the cab of the tractor and at generally horizontal position in a rough terrain, when riding along a steep slope or the like.

Description

~E~ c~ t~ _Y~ w ~YJal~ D~ 7 0~ 605 1 6 ~3 1 ~X~()53 ~ -TRACTOR

The present invention relates to a tra~tor with wheel-moun~ed frame and, ~onne~ted there~o, a driver's c~b.
Many kinds of cros~-country vehicles are already known, with wheel-driv~ or caterpillar-drive. On ~he whole, they ~unction well but ~re ~airly complicated.
It is the ob]e~t o~ the present invention ~o provide a wheel-mounted tractor which is far less sophistica~ed, bu~ nevertheless has cxcellent maneuvP~hility and i~
capable, alsc when movin~ over rDug~ groun~, Df m~
~ainin~ ~he driv~r's cab in a more or le~s horizontal po~ition~ This o~ject i~ a~hieved in that the tra~tor h~ ransverse, ~pprcximA~çly ~entrally posi~ioned pivot axle whi~h at each end is provided with radi~l ~rms pivotally .support~d independently of ea~h other and carrying a wheel at the arm end facing away frcm th~ pivo~ axl~., And in th~ ~ hydr~ulic cylinder is pi-votally connected to e~ch arm and the frame At a point a~ove the arm for controlling the pivot position of the a~m r~lati~e to th~ pivok axle, The inventi~n wiIl ~e described in detail below~
re~erence bein0 h~d to ~he accompanylng drawing~ which illu~trate an emhodiment and in which Pig, 1 i.~ a lateral view ~ ~ t~a~tor a~cording ~o the invention, and Fig. 2 is a rear view of the tr~tor.
The tractor shown in ~he drawings has, in ~on~en~ional manner, A ~rame 10 and a driverls cab 11 ~onnected thereto.
The f rame ~nd th~ ~river's cab can hav~ any suitable fvrm ~nd ~ust not ne~ssArily be designed ~s shown in th~ drawings~ ~ontrary ~o other tractor~, ~he ~ractor according to the invention has only one piv~t axl~ 12 which i~ hollow and ~pproximately ~entrally positioned ~nd in some suitable m~nn~r (not shown) is connected xEFO~ T~iLE~_Q~lER 4~5; :~- 4-86: 4:55~ 4~ 516-3 ~il356;3~;69:# Z
E)45 ~E!5 1 1~; 02 to the fram~ 10. Th~ pivo~ ~xle 12 projects On either side of the ~rame 10, as shown in Fig. ~, ~nd o~ th~
projec~in~ axle portions, on ~ither side of ~he tractor, ~wo arms 1~ are pivotally ~upported at one end. ~he arms 13 are hollow a~d axi~lly nondisplacea~le on the axle 1~ in tha~ the ~rm end portion is disposed in a rece~
in the axle which at its extreme ~nd ha~ a ~etacha~le flange 21. ~he pivotal arm,s 13 have, at the end f~cing ~w~y from the axle 12, a journal box 14 extending in parallel wi.~h the axle l2~ In the box 14 a journal i~
mounted, carryin~ a trac~toL- wheel 15. Inside ~he hollow axle 12, at each end th~sreof, a hydrau1ic motor is m~unted ~or driving th~ tractor wheel s 15, each motor being con-ne~ted tc two chain wheels which a~e positioned oppo~ite the Arms 13 on either side of the tractor . P ~ous~d each chain wheel a chain is pl~ced which ex~ends thr~u~h the assoc~at~d hollow arm 13 And at the ~uter end of the arm is placed around a further chain wheel which i6 i~ixed-ly connected ~o the wheel journal mounted in ~che box 14.
In this manner, one hy~rE~ulic motor drives ~he wheel pair on one si~e of the tractor, while ~he other hydrauli~
motor drives the wheel pair on the other side o~ the tractor, ~nd since the moto~s are driv~n independently of each other, the tra~tor can be ~teered in ~hi~ manner~
In order to control the pivot position of the arms 13 pivotally moun~ed on the pivot axle i~, a hydraulic cylinde~ 16 is provided for ea~h arm 13. The hydraulic cylinders 16 ~rr~nged on either side of ~he trac~or are pivotally mounted, at 1~, in a ~earin~ ~racket 17 ri~idly connec~ed to the ~raçtor frame 10 in a po~ition dir~ctly above the axle 12. At 20, the piston rods of ~he hydraulic ~ylinders are pivotally connected to a bearin~ braeket 18 posi~ioned on the upper side of each arm 13. When ex~ending or retracting a hydraulic cylinde~
16, its asso~i~ted ~rm 13 mounted on ~he pivot axle 12 is pivot~d, such ~hat ~he wheel 1~ of the arm ~an be -' . , 3<EF?~ TE! ECOFIER 4~5; 3- 4-86: 4:56~ 040 6el516~ 613563g~69:# 3 0d,1~ 5 1 6 0~3 0~i3 raised or lowered, ~s shown by the dash and dot li~es at 15' and lS'' in Fig. l~ The hydraulic cylinders 16 are operahle independently of each other, either manu~lly or by means o~ a mi~rocomputer sy.stem.
~ uring cros~-country driving of the tractor accoxd-ing to t~ inven~ion, e~ch wheel may~ ~ men~loned ~bove, be ~isplaced bet.ween the posi~ion~ designated 15' and 15'' independently of khe other ~heels, and thi~ me~ns that the -tra~tor ~an be driven over extr~mely rough and uneven grou~d, while m~intaining the horizontal position of the driver's c~h 11. For this purpose, ~he driver~
c~ pre~er~ly is equipped with a microcomputer sens~n~
the longltud~nal and tran&verse ~ilting tendency o~ ~he dirve~ 1 8 cab and activatin~ one or more hy~raulic cylin-ders to elimi~ate kilting. Sln~e the traGtor h~s but one pivot axle, cons~ruction co~ts arç reduced and, fur-thermore, ~he maneu~e~bility is improved owing to the increased ~round clearance.

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Claims (3)

1. A tractor comprising:
a wheel mounted frame;
a diriver's cab connected to said frame;
a transverse, approximately centrally positioned pivot axle secured to said frame;
radial arms pivotally supported at each end of said axle, independently of each other, each arm having a free end;
a wheel rotatably carried at the free end of each arm;
a hydraulic cylinder pivotally connected to each arm and to the frame at a point above the respective arm for controlling the pivotal position of the respective arm relative to the pivot axle; and a bearing bracket secured to opposite sides of the frame directly above the pivot axle for pivotally mounting the hydraulic cylinders on both sides of the tractor directly above the pivot axle.

2. A tractor as claimed in claim 1, further including means for maintaining the driver's cab in an approximately horizontal position by individually controlling the pivotal position of the arms through the hydraulic cylinders.

3. A tractor as claimed in claim 1, wherein each said hydraulic cylinder is pivotally connected to each respective arm at a posiston between opposite ends thereof.