Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
21~9113
~ 1 --
~E~ RSIB~E~ UGH"
This invention relates to an improved plough having
rotary discs or inversion wheels as the ~eans for turning
the soil and which is reversible.
With modern ploughing tachniques, there has been an
increasing demand for a means o~ ploughing in which surface
debris can be reliably ~uried during the ploughing
operation. With the present invention~ this is achieved by
having a se~uential ploughing operation in which a sliver
is initially li~ted ~rom the soil surface and turned before
the main ploughing action takes over and turns the sub
surface ~oil over to bury the already skimmed surface
layer.
- According tc the present inventiont there isiprovided
a plough comprising:
a frame;
tilling apparatus supported by said frame and
comprising a primary concave ploughing disc rotatable by
reaction with the ground to be tilled and inclined in ~he
direction of forw~rd movement o~ the plough to provide a
~ soil tilling and ploughing action and a sXimmer msunted
I adjacent the primary Ploughing disc and more gr~atly
l; inclined to the d7rection o~ ~orward movement than the
primary ploughing disc, in ~rder to displace a sliver of
soil together wi~h stubble and straw o~f the surface of the
: . ground, the primary ploughing disc being operati~e in use
: of the plough to roll the clean soil from the und~rside of
the ~liYer over to cover the sliv~r of soil, s~ubble and
straw initially displaced~
a point depending from the frame to penetrate the
ground in front of the forward edge of the pri~:~ry
ploughing disc, the skimmer al~o having a forward edge
~ substantially aligned~with ~he point;
: means for pivoting the primary ploughing di c
¦~ 35 rela~ive to the:frame ~etween positions in which it is
oppositely inclined to the direction of forward ~ovement of
.~'NL_':^..,_T
,
21~9113
- la - :
-~ the plough; and
means for pivoting the skimmer, through an angle
smaller than the angle of pivotal movement of the primary
ploughing disc between positions in which it is oppositely
inclined to the dire~tion of forward movement of the
plough.
While the skimmer may itself comprise a secondary,
smaller, ploughing disc, rota~abl~ abou~ its axis, within
the concavity of th~ main ploughing disc, it has been
found, e~pecially with heavier ploughi~g
!: ' ! . I . l I
AMENDr~S~EET
WO 94/1082~ . PCr/G;B93/0~
1 1 ~ .
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conditions, that the preferred skimmer is a fixed skimmer
having a leading edge aligned with and behind a fixed
point initially penetrating the ground and with the main
ploughing disc b~ing behind the fixed skimmer, also with
its leading edge s~stantially aligned ~ith the earth
penetrating point. The skimmer may readily be adjusted in
height to vary the depth of the initial sliver cut from
the ground and ~or use in a reversible plough will be in
the form of ~ lade ha~ring working edge 21t each end with
different ones of the working edges being aligned
initially to turn the ~;oil depending upon the direction of
ploughing, ~n adjustable stop may be provided to vary the
inclirlation of the skim~er blade, relative to the
diraction of movement of the plough.
With a reversible plough where ~ beam from which
: the various plouah bodies :depend is swingable about a
headstock pivot be~ween oppositel y inclined positions
depending upon wh~ther a l~ft-hand or a right-hand ~urrow
is re~uired, there is a requirement to maintain th~
¦ ~ 20 various plough bodi~; parallel, ~ne wi~ the other, during
beam reversal as it is swung fro~ one ploughing position
., to the other and there is a urther problem that the body
angle of th~ plough bodies ~ould be so-controllable ~hat
when the plough is in work, the angl e is such as to enable
the plough tc c:ounteract ~he f2rce~ due to t:ha opposite
ang~e of pull from the tractor to the ~lough~ .
The presen~ invention, in its later illustrated
form, is directed at providing a reversible plough ha!ving
a linkage capable of providing this control of plough body
3 0 dires::tion .
The illustrated form of the present inYentlon
c:omprises a re~rersible plough comprising a headstoc:k fox
atta;:hment at c~ne end to a ~tractor and provided with a
substantially vertical a~is main pivot at its other end, a
beam connec:ted by a riqid support to said main pivot
whereby the beam is spaced ~rom sa d axis and is pivotable
~; ' ' .
-Y`VO 94~10826 21 ~ 9 1 I 3 PCl/GB93/01764
-- 3 --
thereabout in a substantially horizontal plane so as to ~e
inclinable to either side of the direction of movement of
the plough, a plurality of plough bodies pivotally
supported by said be~m for pivoted movem~nt about
S substantially vertical axe~ whereby the plough bodies can
pivot upon pivotal move~ent o~ the beam t~ maintain their
kr~iling position su~stantially parallel with the
direction of movement of the plouqh during pivotal
move~ent of the bea~, a parallelogram linkage havi~g arms
10 ~ixed to ~:aid plough bodies and to a lin}c extending
parallel to the beam, and a ~;econdary pivot co~ecting
said link and the headstock, the secondary pivot being
spas~ed f rom the main piYot towards the 4ront of the
headstoclc and the length of the parallelogram linkage arms
. 15 being such that in all pivotal positions of the beam, the
line of the link bet~reen the points of connection to ~he
arms is located b~3tween the main pivot axis and the beam,
whereby as the beam is pivoted relati~re to ~h~ head~tock,
the plough bodies ar~ controlledl~r pivoted relative to the
2 0 b~am .
. Preferably, the secondary pivot is ~o-located or
locatable that the p~ough bodies ar~ inclined to the
c:entre line o~ the headstock in a position to counteract
the t~ndency o~ the beam to swing due to th resultant
~5 line of pull from the plough bodies being offset rom the
cerltre line of the h~adstockO ~hus, means may be provided
for controllably ~rarying the distance between the
secondaxy pivo~: and the line of ~he link connecting the
ends of the arms while the see:ondary pivot itsel f ~ay be
3 0 positionabl~ relatiY~ to the h~adstock O Such positioning
may be along a locu~ e~tending along the length or at an
~ngle to the length of the headstodc or, in another
embodiment, may. be along an arc centred on a fixed axis of
the headstoc:k.
3~ ~n a pr~ferrQd, si~;:ple, con~tnlcti~n, the link
s in the form of an isosceles triangle frame with the
~9 ~3
W0~4~10826 PCT/GB93/01
ends of its bas~ being pivotally connected to the arms and
its apex beinq connect~d to the headstock at said
secondary pivot.
Preferab~y, th~ plough has rotary inversion
wheels as the soil turning m ~ ers, with these members
comprising a ~lat ! or substantially ~lat, central disc,
provided with a frustoconic~l working flange at its
periphery, In the illustrated e~bodiment, thi~ flange is
provided by a number of ~e~th, indi~idually d~tachably
s~cured to the periphery of the central disc.
; . The i~vention will be further described, by way
of example, with re~erence to th~ accompanying drawings,
in which:-
Figur2 1 is a plan view of a reversible plough;
:1 15 Fi~ure 2 is a diagrammatic view illustrating the
, ~ construction for contro11ing the direction of operation of
~1l ploughing bodies:
: Fi~ure 3 is a diagram~further illustrating the
operation of the plough;
2Q Figure 4 is a view similar to Fi ~ re 3 but
. ~ illustrating a modified construction;
., Figure S is a plan Yi~W of th~ beam of the
plough of Figura l;
~! Fi~ure 6 is a plan view of the headstock of th~
; 25 plaugh;
: Figure 7 i an elevational view of the
eads ock;
Fiyure 8 is an end view nf the headstock;~ j
I ! Figure 9 is a part fragmentary view illustrating
:~ ~ 30 a plough body:provided with ~ rotary dis~ from ~he front
with the rotary d:isc arranged in a:non-ploughing conditi~n
at right-angles to the direction of extent of the plough
: ~ body;
igu~ 10 is a side elevational view of the
plough body of Figure 9;:
: Figure ll is~a sectional view illustrating ~he
WO 94~10826 PCIi/GB93/0l764
2l~9ll3
-- 5 --
mnunti~g f or the r~tary disc;
Figure 12 is a top view of the plough body with
the rotary diec re~oved;
Fi~re 13 is a diagrammatiz ~Iriew illustrating an
S alternativ~ form of link for U52 in the plough; and
Figure 14 is a diagrammatic view explaining the
theoretical basis ~or th2 control linkage used in the
plough .
Figure 15 i8 a diagrammatio plan ~iew showing
the relative positions o~ skilDmer and plough inversion
wheel for ploughing in one direction.
Figure 16 is a Yiew similar to Figure 15 but
showing the in~ersion wheel aTld skimmer arran~ed for
ploughing in the opposite direction.
Figure 17 is an end view of a skimmer blade.
Figure 1~ i~ a front view of the blade of Figure
17 O
Figure 19 is a front ~riew of an alternati~Je
embodiment of ~kimmer blade, and
Figure 20 is a top ~i@W of the blade of Figure
19 ~
Pc~erring to the drawings, Figure ~ ustrates
a plough whic:h comprises a headstoc:k 2 pro~rided w~ th
outw~rdly e2rtendin~ retaining brackets 4 which are
engageable with brac:k~ts 6 on a beam 8 for retair~ing the
beam in either of two limiting positions inclirled to the
centre line of th@ headstock. ~h~le, in this embodiment,
two working positions only are showrl ~ by aE~propriate
redesigning o~ the brackets 4 and 6 more than orle working
position may be pro~rided on eac:h side of the centre line,
the plough bodies ~ being correctly aligTI~d by the linkage
to be des ::ribed regardless of the degree of inclination of
th~ beam adopted..: The b am lt . elf compri es a rigid
supp~rt 9 comprising a bearing 11 for mounting to a
3 5 vertical axis ma~n pivot P at the rear end of the
headstock 2. Wheels 10 are provided fQr supporting the
WO 94/10826 ; ; 2 f 4 9113 PC~/GB93/01~
plough baam in its ploughing p~sition with these wheels
being mounted on struts rotatable about pivots 18 at the
end of the beam, these pivots also ~upporting outermost
plough bodies 12 which a~e rot:atable wit;h the wheel
5 supports about the pivot axis l8. Rotatiorl of the beam 8
about the pivot P is controlled by a hydraulic c:ylinder 2 0
. ha~ing a piston connected at 22 to an arm projecting to
th~ side of the rigid ~;uppo~ 9.
The c:ons~ructiQn of th~ individual plough bodies
10 12 will be described later, with refarence to Figures 9,
lO, ll and 12.
With the plough as illustrated in Figure 1, in
the position shown, upon forward movement of the plough,
the rotary plough discs or inversion wheels will turn soil
lS to the left to form the requi~ed furrowsO However, due to
the fact that the resultant fs:~rce required to pull the
.~ plough l~odies is displaced to one side of the centre line
i o~ the main pivot P, ther~ would b~ a tendency, where the
¦ plough bodies are parallel with ~he line o~ ~xten~ of the
~0 ploughing ~or them to pull sideways bn the tractor with
resultant ~raction difficulties., In ~rder to osrercome
this probl~m, th~ plough bodies as sh~wn in th~ e~odiment
of Figure 1 are inclined slightly to the longitudinal
~ centra line o~ the head~tock a~d the direction of:
: : 25~ ploughing so~as to apply a:sideways force which
: coun~eracts the eff~ct of their b~ing ~o one side of the
:~ ; centre line. ~hen the beam is r~tated so as to be
oppositely inclined to ~th~ direc~ion of pIou~hing, th~
plough ~odies are arranged ko b~ inclined them ~lves
30 ~appropriat~1y to provide the:oppo~ correcting force
:~ with the oppositely inclined b~amO
: ~ A~c~rdingly, with the illustrated plo~gh, ther
has been d~signed a l~inkage to maintain the plou~h bodies
: parallel~t~ one another during beam~rPversal and to have
35 the body arlgle variable~ when the plough is in work. The
variable angle; is ~o counterac~ the forces due to the
.
: - ~
yvo94/lo826 21~9113 PCI/GB93/01764
-- 7
of :Eset angle of pull from trac:tor to plough . In the
particular case of ~e plough l :hown, designed to run out
of t:h~ furrow, th~ bodies must be biased to pull away from
the centre line of the tractor to maintain fitability.
Figure 2 diagrammatically illustrate a linkage
arrangament for c:ontrolling the angle Q~ plough b4dies
resporlsive to p~ Yotal move~Rent of the beam., Thus,
refarring to this Figure, ~e b~am 8 casl be ~een a~
pivoting about ~he point P on th~ ~eadstock with EB and FC
being two arms c~ntrolling the angle of the plough bodies
with the lens~h of EB being equal to FC. The~;e arms are
shows~ in Figure 1 by ref rence numeral ~ 5 0
EB and FC are constrained to remain parallel one
with the other by the link ESC which is the a;ame length as
EF. In the form illustrated BDC is the base of a rigid
triangular link frame ABC with the trian~lar link being
an isosceles l;riangle so f o~ed that AD equals PG, where G
is the mid-point of EF, and D i5 the mid-point of BC with
AB eS~ual to A~C and BD equal tcs 13CQ With th~ e
constra~ ts, AP must equal BE and CF, and AP, BE and CF
will remain parallel when the beam rotate~ a}:~out pivot
point P.
~his system can be considered as r~presenting a
paix of parallelogram lin};ages APFC and APEB lir~ed by a
third parallelogra~a lin Icage BCFE and allows the
parallelogram linkage APFG to go ov~r-ce~tre when the beam
is ro~:ated anticloc:kwise while the linkage parallelogram
APEB mairltairls control.
This linkage can be considered mathematic:ally by
visualising a pha~tom link connected between the mid-point
of EF (which by def initiQn is G) and point D on the
triangular li~age. l)G is- the ame length a~ BE and CF
and always remains parallel with them. A~ so, instead of
using the triangular lirlk, the lîne A~ may be c:onsider~d
3 5 instead as being perpendicular tv the original connecting
link BC, and also the line EFq Thus although for
WO 94/10826 214 9113 PCI/GB93J017 ~
structural reasons we have shown the 1 ink as being
triangular, it can be of any con~enient f orm, provided
tllat it defines the locations of the pointg B, C and A.
With the above explanation, one obtains the
5 geometric diagram il~u~;trated in Figur~ 3. Where AP~;D
becomes a new parallel linkage, it i. clear t:hat because
of the rigid nature of the triangular link, the proj ection
of ~D onto the line EGF will always be p~rpendicular since
by c:orlstruc:tion th~ beam assembly PG is perperldicular to
10 the line EF.
While, in the abo~re explanation, the point ~ has
been considered as being a f ixed pi~rot point on the centre
line of the frame, position ~ could be ~risualised as being
able to slide along ~he line AP, i. e. that t~ere is no
15 fixed link between ~ arld P. The point A would ski}l,
however, remain in a fixed position relatiYe to P because
DG is a fixed length and AD and PG must relaain parallel to
each other, as defined as the visuali~ed li ~age was
described. Having adopted t~e possibility of haYing a
slide a~ A the~ the poss~bility exists to alter ~he
dimensions of the link AD, . ill ~aintaining AD parallel
to PG. Lengthening or shortenin~ ~he leng~h AD will
rotate DG so that it is not parallel to~AP.
This idea can be taken one stage ~urther in that
the point A need not necessarily slide along the lîne AP.
~hus, as shown in Figure 4~, the con~ept is introduced of
point A being allowed to slide along a loaus J~. The
positio~ of A and length AD do not neces~arily constrain
~G paral1el to ~PH a~d ~he variation from parallel will be
a function of the po~ition~of point ~ along the locus AK
: and the r~lative lengths of AD, DG and PG and tha angle HH
~ubtended by the be~m. The constraint that AD is parallel
to PG still exi~ts,
The plough illustrated in Fi~ure 1 utilises a
fixed triangular~linkage with the secondary piYot A being
received within ~ slipper pad h2ving a variable degree of
- ~WO 94/10826 21 ~ 91 1 3 P~/GB93/01764
angular movement. However, as will be discussed later,
either wi~ this arrangement or with a ~;lipper f ixed to
the centre 1 ine o~ the plc: ugh h adstock advarltages can be
appreciated by having what is ef f ectivel~ a triangular
5 link with a ~ariable geometry. Such a triangular linlc
could be made as showrl in Fisure 13 where the triangular
link is shown as comprising a base 26 connecting the
pi~ots B and C, two sides 27 and 28 welded to an outer 3:ox
section 30 and an inner bo~ section 32 ~li dable within the
10 outer box s~ction 34 along the centre line of the
triangular link. The position of the inner box ~ec:tion
along the length o~ the outer box sectioIl is ::ontrollable
by a threaded member 3 4 . The bax section 3 2 carries a
bearing 36 for engagement with the pivot A. It will be
15 appreciated that in Figllre 13 the beam is shown in its
mid-position, between its normal ploughing positions
extending transv~rsely of the direction of ploughing.
We will explain later, in connection with Figure
14, the mathe~atiaal bat:Jcground to the ~mbodimenks
20 illustrated.
R~vertiIlg to the parti~ular construction of the
plough shown in Figure 1, the headstock is illustrated in
Figures 6, 7 and 8. The headstock c:omprises a trian~lar
base f raIae having the pivot P at its r~arward end and
25 provided with lower c:onnecting members 40 at its forward
end. An upper pivot conn~cti on 44 is connected by a
central sloping member 46 and two ïateral sloping mem~ers
42 to the base frame. Forward of the pivot point P there
is provided a mounting for the apex of the triangular ~ ink
3 Q which comprises a platf orm 52 ha~ring an upstanding mem}~er
50 defining a re~rwardly openirlg rece ~ with diverging
sides. A hole 54 is pro~ided in this mounting plat:e 52 to
provide a f ixed vertical axis ~or receiving a 3:)olt 54 '
wh.ich pi~otally retains a pivot supporting member 56 which
35 carries the se ::ondary pi~ot P~O The pivot supporting
member 56 i~ ~hus pivotal between limiting positions in
WO 94/10826 ~,, 49~3 PCl/GB93/0l '!
-- 10 --
engagement with the diverging walls of the meInber 50, the
secondary pivot ~ being displaceable about a radius
centred on the axi~ o the hole 54.
W~th thi5 arrangement, as shown in Figure 1, ths
5 pivot point A is offset to one ~ide of` the cen~r~ of the
headstock 46 with the result that with the beam in its
inclined ploughing position shown in this Figure, the
plough bodies will be in~::lined to the centre line of the
headstock to th~ required ~xt~, to provide the corrected
10 bias. When the direction of th~ plough is rev~rsed so
that the beam is swung round to the other side of the
headstock, the pivotable member 55 will it~;elf rock to
engage the opposite side of the rece s provided }:~y the
member 50 with the pivot point A t~en being on the
15 opposite side of the centre line of the headstock with the
result that the appropriate alignment of the plough ~3odies
is achieved.
Figure~ 9 to 12 illu~:trate the constructio~ of
the plou~h bodi~ the~selves. As shot~m in these ~iç~res,
20 the rotary disc: is not shown in its operative po-~ition but
i~ shown arranged to extend with its plan~ perpendicular
to the line of extent of the plough body.
The plough body is illustrated detached from the
remainder of the plough and comprises an upper L~shaped
25 fram~ member 60 haviT~g a lower extension 62 weld~d ~ereto
with the exterlsion ~2 being connec:ted by bolts 63 to a
downward~y dep~nding leg 64 provided at its fr~nt edge
with a soil penetrating or cutting member ~6S Asl ~3hown,
the member 66 is bolted into position and is reversible so
30 that as ~he point 67 wear~;, it can simply be adjusted down
using a plurality of bolt hole~ proYided on the leg 64 to
permit adjusting of the positioT~ sf the soil pen~trati~g
alement 66 to take up for shortening of the member in use.
Once the limit of adjustment has been rPached, the meDIber
3 5 6 6 can s imply be removed and reversed to use the other
point 67.
-~094/10826 æ~ ~3I13 PCr/GB93tOI764
Extending rearwardly from the leg 64 is a
landslide 6B whic:h extends beneath a rotary ~oil inversion
wheel 90. R~arwardly of the ~oil in~rPrsion wh~el 90 a
post 70 is upstanding from the landslide and secured by
bolt 73 to a member 72 which has a~ upper flange providing
a suppor~ 74 for the lower end l~f a shaft 76.
The frame memb~r 60 i~ adapted to be secllred to
bodies piYotally mount~d on t:he p~vots E,F and 18 by
members 80 and 81 (Figure 1) extending rearwardly from the
~0 bodies mc~unted on the pivots. Carried by the rearwardly
extending portion of th~ frame 60 i5 a body B2 which
carxies at its rearward end a support 8~ for the upper end
of the sha~t 76. The shaft 76 rotatably mounts a sleeve
84 proYided with grease nipples 85. P~lso carried by the
15 frame mensber 8~ are a pair of adjustable stops 88 which
limit rotakion o~ the sleeve 84 by c:ooperatirlg with a stop
92 rc~tatable with the sleeve ~4. Secured ts:s the sleeve 84
i~ a plate 9~ which extends ~orwardly and has a laterally
projecting portion to which is secured a pivot 96 for
2 O attachment to the end o~ a piston coc~perable with a
hydraulîc cylindQr 97. At the low~r end of the slee~e,
there is provided a bearing 100 ~or mounting a rotatabl~
hub 98. Secured 1:o the forward end o~ th~ hub 98 is an
in~rersion whee} mountis~g plate 102 to which i~ secured by
25 bolts 103 the central planar plate ~04 of i~version wheel
90. The working por1;ion of the irlversion wheel ~0 can be
considered as being c:onstituted ~y an annular
frustocorllc:al flange ~;e ::ured to th~ periphery s:~ the
central disc portion }04 by bolts 105. In the embodiment
30 shown, the worl~ing flar~ge is constitu~ed by a plurality o~
separate teeth 10 6 bolted to the periph~ry of the central
disc portio~ although other forms of flang~ ~re possible,
for exa~nple a continuous flange which may have a smc)oth
edge, a toothed edge ~ an undulating edge or any other edge
3 5 f ormation as conside;red desirable; depending upon the
environment in which the plough is to be usPd.
WO 94/lû8t6 Z 1 ~ 9 1~3 PCrlGB93/0
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To the forward end of the pla~e 94 there is
provîded a do~nwardly extending sc:raper 108 which is
cooperable with the inversion wheel durin~ use of the
E~lough .
To the top of the body 82, there is provided a
pivot shaft 110 for receipt within a bore at the end of a
::olmecting bar 112. A.s can be seen in Figure 1, the
connecting bar 112 extends between the rod~ llO extending
upwardly from two neighbouring plough bodies in order to
ensure that the plough bodies remain parallel one with the
other .
Also shown in Figure lQ is a support 150 for use
in detacha:bly mounting a secondary ploughing disc
operative as disclosed in my earlier GB-A-2 254 232 or for
mounting a f ixed skimmer blade as later de~c:ribed ~,
5upport 150 depends from a plate 154 which is rotatable
about the shaft 86 independently of the sleeve 84. A pair
of stops 152, which may be adjustable, projact upward ~rom
the plate 94 E;O that ~?on operatio~s o~ the hydraulic
cylinder ~7 to reverse the angle of in~lination of the .
in~ersion wheel 90, the plate 94 will r6:tate until such
time as a stop 152 engages the plate 154 to displace the
plat~3 154 throu~h the remainder o~ 3 rotational movement
o~ the plate 94 with th~ result that the plate 154 is
swung through a smaller angle than the angle through which
the plate 94 is turned. Conversely, upon return movement
of the lplate 9~, stop 1~2 is only engageable with the
plate 154 for th~ latter part of the mo~emen- of the plate
94 withl the result that th~ required smaller degree of
pivoting movement of thQ p~.ate 154 i required.
A}ternatively, the plate 154 may be pivoted ~Eor swinging
movem~nt about an axis f ormed of the axis of the swinging
movement of the main ploughing disc a~ will be described
with reference to Fig~res 15 anà 16.
3 5 Although not ~;hown in Figure 10, the box 150
serves as a ~apport for a detachable secondary ploughing
Y,VO 94~ 1 0826 2 1 ~ 9 11 3 P~r/GB93~01 764
-- 13
disc which will be molmted in front of the main ploughing
disc or inver~;ion wheel 90 w~th its leading edge
substantially aligne~ with the leg 64. With the secondary
ploughing disc in position with its E;uppor~ mounted
5 depending from the box a;ection 150, the tilling apparatu~
can be seen to comprise the primary concave ploughillg disc
90 rotatable by reactioll with the grourld to be tilled and
in::lined to th~ direction of forward move~e~at to pro~ride a
soil tilling and ploughing action arld the secondary,
smaller, ploughin~ disc mounted within the concavity of
the primary ploughing disr~ and more greatly inclined to
the dire~tion of f orward movement in order to displace a
s}iver of soil, toge'cher with stubble and ~traw off the
surf ace of th~ ground, the primary ploughing disc: being
operati~e in use o~ the plough to roll the clean soil from
th~ underside of the sliYer over to cover the sliYer of
soil, stubble and str~w initially displaced, the secondary
ploughing disc: being rotatable about its axis. The
~orward edge~ o~E both the ~;econdary and the primary
ploughing discs ar~ substantially aligned with the point
66 and 1 eg 64 . The g:ec:ondary ploughing disc may be a soil
inversion wheel cons~r~ction with a flat central disc as
for the main ploughing disc althou~ in some circumstaIlces
a simple concave disc: may be utilised. A ~mall scraper
may be pro~icled Zl ~ociated with the secondary ploughin
disc to operate in a manner similar to that in which th~
sc~rap~r 108 operates with the main ~;oil in~ersion wheel
90. Alternat:ively, instead of t~Le ~;ec:ondlary ploughing
disc, a non-rotatable skimmer blad~3 may be used as later
described with reference to Figures 15 tc~ 20.
In use of the plough t it can be seen that in one
norma} working position for producing left-hand furrows,
the plo~lgh will be in the position as æhowrl in Figure 1
with the beam having been incl ined about the main pivot P
until the left-hand retainers 4 and 6 have engaged. In
that positiorl, the linkage comprising the main triangular
WO 94~10826 PC~/GB93/01- j
~49113
-- 14 -
link 26, 27, 28 s::ontrols the position of the two innermostplough bodies so that they are slightly out of parallel
with the direction o~ movement of the plough, in order to
provide a correcting bia~, assisting straight traction by
5 the tractor. The outarmost plough bodies are maintainPd
parallel with the two inner controlled plough bodies by
the cormecting bars 112.
When it is desired to reverse the direction of
the plough, t~e ::yl i nder 25 can be actuated to rotate the
10 beam 8 about khe main pivot P until the right-hand
retainers 4 and 6 are engaged. During this rotatlon, the
p- ough bodies will automatically be, them~elves, rotated
relative to the beam so as to reach th~ desired
orientation, slightly non-para3 lel, in the opposite sense,
15 with the direction of motion of the plouyh. P.t the same
timel the inversion wheels are, themselves, moved from the
worlcing position shn~m in Figure 1 i:o an oppositely
inclined working position relative to the plough body by
, operation of thQ cylind~rs 97.... The limitin~ rotating
positions of the inversion whee~ relative to the plough
body are controlled by t~e adjustable stops ~8.
As ~urther explanation j there will now be
described in connectio~ with Figure 14, the mathematical
~xplana~ion ~f the linkage used ~or cc)ntrolling the
angular position of the plough ~odies. This ~an be
expressed as having a problem to ~how the body steering
angle GG in terms e: f the ~;lider aslgle JJ, th2 beam angl .
HH and the link l~nqth AD. The lengths PG (beam o~fset~,
iPG (leYer arm) ~ JP ~slider pivot position~, can be
3 0 considered as the required data sinee, due to th~
collstraints imposed in the practical linkage, Al:) must
always be parallel to PG. In ~igure 14 ~ JA and G~? have
}~en produced to meet at R and GL lhas been drawn parallel
to JA to meet I~D produced at M8
The method that i5 applied is to use the
parallelogram AXGM ~o de~erminP the length of DM and by
-~O 94~10826 214 9113 PC~/GB93~01764
- 15 ~
applying thè sine rule to triangle DGM to f ind the angle
DG.
.
~ ~ .
WO 94/l08~6 214 9 1il 3 PCI/GB93/~
-- 16 --
First, f ind KP by applyin~ the sine rule to
triangle J~P.
KP JP
S inJJ 5 ~ / Z +~ D
Therefore KP = JP Sin ~J
C;: s (HH~JJ)
clearly D~ = KP + PG - AD 2
f rom 1 and 2
J~ S in JJ + p~; AD
C~s (HH JJ~
now, applying the sine nlle to triangle DMG
DM = DG
Sin (JJ-G~) si~ /2~ ~~~l~il~
hence Sin (JJ-GG) G ~ Cos (~ D)
DG
and GG a JJ ~ Sin 1 [ ~ Cos(~ D~ ] 4
, D~;
and el iminating DM f rom 3 and 4
GG - JJ ~ Sin~1 [ JPsin JJ ~ ( ~ cos~H~~JJ) ¦ 5
DG ~X;
E~ua i:ion 5 is the general expres~ion relating
angle GG . in terms of angles JJ and GG and length AD with
giverl len~ths JP, DG, PG and AD.
If ~z more particular case wh~re the slider
angle ig always~ zero, as is~ the embodim~nt of Fi~re 13,
and GG is controlled by ~aryin~ AD, then equation 5
reduces to
GG = -Sin 1 [ ( AD) Cos ~HH-JJ) ] 5a
D~
-~1~ 94/10826 . ; 1 ~9i 13 PCr~G;B93/0l764
-- 17 --
Figures 15 and 16 diagrammatically illustrate a
constructiorl using a non rotatable ~kimmer blade 204,
dependins~ from a pivotal arm 154 which, instead of being
swingable about the axis 2 00 abou~ which the arm 98
5 carrying the inversion wheel 90 is swingable, is swingable
relative to the plcugh body about a vertic:al axis 202
forward of the axis 200. The skimmer blade 204 will, in
use of the plough, be the sama side of l:he landslide 68 as
the main tilling inversion wheel or disc ~ ~0 with the
10 fc~rward c:utting edge ~ of the blade 204 beLng substantially
aligned behind the point 67 as is the forward edge of the
i~er~ion wheel 90.
q~he! mounting o~ the~ blade 204 is shown in
greater detail in Figures 17 and 18 where a tube 2 06
15 depends from the arm~l54. The s~ppor~: rod 208 is
telesc:opica}ly receivable in the tube 206 so as to permit
vertical adjustment of the height of the cki~mer blade 204
i relati~re to the plough body. The skim~er blade 20.
; ~ ::omprises a c:urved main portion with a bottom wear blade
20 2~0 detachably secured to: the bottom ~of ~e blade, for
~: ~ example by means of bolts, :not shown.~ Both ends of the
blade 204 have working edg~s which;will be alternati~ely
:1 aligned with ~he point 67 depending:upon ~he direction of
ploughing and whether left- or ri~ht-hand ploughing is:
: as being carried vut. An alternative shape of skimmer blade
212 is shown~in Figure 19 and 20. ~: ~
In each case, the skimmer will serve to turn a
.sliver of the!~:top~urface and deb~iq~from th$ gr~und ~eing
ploughed before the main full depth ploughing is achie~ed
: 30 using the inversion:wheel` which~uries~the materiaI turned
by~the~:fixed~skimmer blade~with ea:rth~turned up ~rom
below.
djustable stops can be:provi~ed to limit th~
swinging:movement of the~arm 154, pre~erably both tha
height o~ the:~skimmer blade~and of the in~ersion wheel 90
:is adjustable. ~he incl~ination of the skimmer, wheth2r a
,
WO 94J10826 214 9113 PCr/GB93/01-
-- 18 --
blade or a rotary discI preiferably also is adjustable
relative ~o the ground. The inc~ination to the horizontal
c:an ba adjusted by inc:lining the axis about which the arm
carrying the ikimmer is pi~,rc~table or by adju~ting the
5 inclination of the skiDer relative to the arm t 154 ~ by
which it is carried.
, ~
