AU592083B2 - Improved draught frame - Google Patents

Description

AV Al 5 6 922r WORLD [INTELLECTUAL PROPERTY OROhiNAi PCT International Bureau INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 4 International Publication Number: WO 86/ 056:531 AOLB 59/042 Al (43) International Publication Date: 9 October 1986 (09.10,86) (21) International Application Number: PCT/AU86/00083 (22) International Filing Date: 27 March 1986 (27.03.8L.

(3Y) Priority Application Number: (32) Priority Date: (33) Priority Country: PG 9968 29 iMarch 1985 (29.03.85) (81) Designated States: AT (European patent), AU, BE (European patent), BR, CH (European patent), DE (European patent), FR (European patent), GB (European patent), HU, IT (European patent), LU (European patent), NL (European patent), RO, SD, SE (European patent), SU, US.

Published 11his do)'_Urnnt ContinUI lte With internationa, fq~hmtrrts made undcr Suc:tiofl 49 and is correct for A.O.Jpprinting.

2. NOA V 1986 (71) Applicant-Ifor all-des-ign a-ted Statres exycept U-S) -A-R---I1NDUSTRIE-S PTY. LTD. [AU/AUI-; 202 -Noruth--Strveet 4 Albu-r-y, N&-W 2640 (A-U- (72) Inventor; and Inventor/Applicant (for US only) :REMPE, Hendrik [AU/AU]; 5 C Lover Avenue, Wodonga, VIC 3690 (A (74) Agent: -C-OW4V--E,--T-HOMSO.N-&-CAR-T-RR+-7--Queens ___Road,1vMelbaurne,-VJG -300,4- (A-14-.

lOIN 3-41 lu wt t..r S6~E q1~ QRECT ED P-6k m f:Lsil~ i N &1-11 (54) Title: IMPROVED DRAUGHT FRAME 3b 3 3 51 j~ \J 193 (57) Abstract A draught frame for a towed vehicle, such as a cultivator has a draw bar (16) with a rearwardly extending' section (34) overlying the front part of the cultivator main frame Draug-ht loads are transferred between the main frame (14) and the depending section (34) by a pair of arms (38, 39) pivoted on transverse pivot axes (41, 42, 43). The relative angle between the arms (38, 39) and the spacing thereof result in the arms defining an instantaneous centre (47) through which the resultant of the draught forces act.

r WO 86/05653 PCT/A U86/00083 -1- IMPROVED DRAUGHT FRAME Background of the Invention This invention relates to an improved draught frame and relates particularly to an improved draught frame for tillage equipment, earth working equipment and the like adapted to be towed by a prime mover such as a tractor.

Tillage implements such as.cultivators and ploughs are generally constructed for towing by a prime mover and are connected to the prime mover by means of a draught frame which is integral with or rigidly connected to the working frame of the implement. The draught forces comprise the towing force applied through the connection of the implement with the prime mover and acts along a line substantially parallel with the ground and spaced above the ground by a distance corresponding to the hitching height. This force is counteracted by the substantially horizontal forces acting on the ground working tools.

The ground working tools may be tines, plough shares, scraper blades, rippers or the like, and the forces acting on those tools acts in a direction opposite to the draught force at some point on or below the surface of the ground.

The vertical displacement of these forces i.e. the draught force and the resistant force, constitutes an unbalancing couple, the resulting moment of which tends to rotate the implement about a transverse line causing variations in tool penetration depth and control.

With agricultural tillage implements such as cultivators, the resultant moment is counteracted to some I degree'by the weight of the implement as well as, in some cases, by the shape of the implement tools engaged in the ground.

However, as the resistant force varies in accordance with soil consistency, depth of penetration, tool condition, nature of terrain and numerous other factors, it is virtually impossible to maintain constant depth of penetration of the working tools. Further, constant depth control of both the forward and rear portions of the

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WO 86/05653 PCT/A L86/OC -2implemert is extremely difficult due to instantaneous variations in tI.e unbalancing cc.uple. These difficulties are particularly noticeable in seed bed preparation and seeding operations when the depth of seeding must be critically controlled.

Background Art Various forms of draught frame and draw bar constructions have been proposed in an endeavour to reduce the aforesaid -problems. However, while some constructions utilizing a pivoted draw bar with front and rear wheels to follow contours do result in an improved control of tool penetration, the unbalancing couple remains to cause errors in operating control.

European Patent Application 84302810.1 (Publication No. 0 123 561) discloses a flexible tine harrow for seed bed preparation, the harrow comprising a numiber of separate harrow sections each having an intermediate frame supported by front and rear drums. The intermediate frames are connected to a main frame through a front, fixed length link at the front of the intermediate frame and by a telescopic stay biased to extension and arranged above the harrow sections.

The direction of push and pull forces exerted through the link connection and the stay result in a horizontal resultant force at tne point of intersection on a level with the harrow tines which reduces or balances the ufibalancing couple.

However, the flexible tine harrow construction disclosed reguires three separate frame structures interconnected-to permit relative angular adjustment, the frame sections being individually supported on drums and rearwardly disposed wheels. The structure does not readily lend itself to relatively heavy ploughs and cultivatrr equipment.

it is therefore an object of the present invention to provide an improved draught frame structure which goes someway towards overcoming problems of the known draught 083 ii 0 0 0 0 Ii

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ii 11 WO 86/05653 PCT/A U86/00083 -3frames.

It is also an object of the invention to provide draw bar and draught frame structures which enable increased control of working tool ground penetration.

It is also desirable to provide agricultural implements having means to avoid at least some of the difficulties noted above.

It is also desirable to provide agricultural or other equipment with an improved draught frame arrangement to minimize variations in soil penetration of the working tools.

It is further desirable to provide draw bar and draught frame structures having an' interconnecting arrangement to effectively move the plane of interconnection away from the plane of actual connection.

It is further desirable to provide an improved draught frame whereby the resistance forces on the implement being moved are effectively transferred to vertical forces on the prime mover tow bar.

Summary of the Invention According to one aspect of the invention there is provided a connection between the working frame means of an agricultural implement and a. draught frame means, said connection comprising a pair of longitudinally spaced links pivotally interconnected to each of the working frame means and draught frame means, the pivotal interconnection being-arranged such that a line containing the axes of the pivotal connection of one link intersects a line containing the axes of the pivotal connection of the other link at a desired point spaced below the working frame means.

Preferably, the desired point is at or below the siirface of the ground near the level at which soil resistance is applied to working tools on the working frame means.

The linkage creates a virtual hinge point at the point of intersection of the lines connecting the axes

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i4 WO 86/05653 PCT/AU86/00083 4of the pivotal connections which causes the working frame to act as if it were flexibly connected to the draught frame means by a hinge located at the instantaneous intersection of the intersecting lines. Thus, the force couple normally produced by the draught and soil resistance is removed from the working part of the implement and transferred to another part where its effect does not adversely affect the operation of the implement. By suitable proportion, the desired point of intersection can be caused to lie in the plane of the soil resistance forces thereby eliminating any rotative moment from the working frame means.

It will be understood that, with this arrangement, by placing support wheels at the front and rear of the working frame means, the workirg frame is able to follow soil undulations without significant changes in depth of penetration between the front and rear of the working frame means. This is of vital importance in tillage and sowing operations.

According to another aspect of the invention there is provided a draught frame structure comprising a draw bar means having a front end to be connected to a prime mover, equipment frame means supported on wheels, and first and second load transfer parts to transfer draught and resistance forces between the draw bar means and the equipment frame means, said first and second load transfer parts-interacting to define an instantaneous centre through which the resultant of the draught and resistance forces act.

In a preferred form of structure, such as an agricultural implement, the first and second load transfer parts comprise a pair of longitudinally spaced arms one end of each of which is pivotally connected to the draw bar means and the other end of each of which is pivotally connected to the frame means, the pivotal connection axis extending transversely and being so located that lines passing through the respective connections for each arm

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WO 86/05653 PCT/A L 86/00083 intersect at or adjacent the horizontal planie along wiic.

the resistance forces act.

In another form, the first and second load transfer parts comprise a curved track member mounted on either the draw bar or frame means and interacting roller means mounted on the other, the curved track means having an instantaneous centre at or adjacent the plane along which the resistance forces act and the roller means transmitting draught forces in the direction of the instantaneous radius of said curved track corresponding to the roller means position.

The invention more part'cularly comprises an agricultural implement comprising a main frame carrying ground working tools, wheels supporting the main frame above the ground, a draw bar to connect the main frame to a prime mover, the draw bar having two legs diverging rearwardly from the front thereof and terminating in spaced, substantially parallel rear end portions overlying a front part of the main frame, a pair of front links connected by transverse pivots to the respective rear end portions and the main frame, the front links extending downwardly and rearwardly from the rear end portions of the draw bar legs, a rear link longitudinally spaced from each respective front link and connected by transverse pivots to the respective rear end portions and the main frame, the rear links extending downwardly and forwardly from the rear end portions.

In one embodiment, the front and rear links of each pair define lines which intersect at or near ground level at any instance during use. Thus, the effective draught force on the main frame acts at about the same level as the resistance forces thereby reducing or removing the couple tending to unbalance the implement.

By effectively lowering the line of action of the draught forces, the power required to move the implement is substantially reduced, the control of tool penetration is substantially increased and the accuracy of penetration WO 36/05653 PCT/-U86/00081 -6control is greatly enhanced. The invention is thoratf ot particular advantage for cultivators and seeders.

In order that the invention is more readi,'.

understood and able to be put into practical effect, embodiments thereof will now be described with referen.>, to the accompanying drawings.

Description of the Drawings Figure 1 is a part top plan view of a cultivator incorporating the structure of the invention, Figure 2 is an enlarged part plan view illustratinj features of the invention shown in Figure 1, Figure 3 is a part sectional side elevational view of the cultivator of Figure 1, Figures 4 to 6 are further side elevational views showing operational features of the invention, and Figure 7 is a side elevational view of another embodiment of the invention.

Description of the Preferred Embodiments Referring to Figures 1 to 3 of the drawings there is illustrattI a cultivator 12 which is adapted to be towed by a prime mover (not shown). The cultivator 12 comprises a main working frame 14 carrying cultivator tines 22. A side frame 15, also carrying cultivator tines 22, is pivotally mounted on each. side of the main frame 14 by pivot mounts 20. Only a portion of the side frames is illustrated in the drawings. Wheels are provided on the outer ends of the side frames 15 for support thereof.

The main frame 14 is supported above the ground by a pair of rear wheels 21 and two pairs of front wheels 23. The wheels of each front pair 2: are carried by a longitudinally extending beam 24 pivotally connected at approximately its midpoint to a transv~rsely extending torque box 26. The torque box 26, in turn, is carried by a pair of bell crank levers 27 which is pivoted to the main frame 14.

The rear wheels 21 are each carried by an arm 28 pivoted to the main frame 14 anid connected, at one end, '1WO 86/05653 PCT/A L 86/00091 to the respective bell crank lever 27 by a~ tonsio~.- 29. A hydraulic cylinder 31 is connected bet-6een the ma~l frame 14 and each bell crank lever 27 whureby the rolat--." height of the main frame 14 can be adjusted by altering relative positions of the bell crank lovers 27, tharm 28 and the associated rear and front whoolo 21 an~d 23.

Movement of the main. frame 14 isoeffectod by draught frame 16 connected to the prime mover. Thedru..

frame f:6 comprises two rearwardly extending, di~verging legs 32 attached by locating pins 33 to substantially parallel, depending sections 34 which are interconnected by a transverse tubular member 36.

The draught frame 16 is connected to the main frame 14 by two pairs of arms 38, 39 pivotall~y mounted to the depending sections 34 and the main frame 14. The front arm 38 of each pair is of an inverted Y configuration.

The upper part of each front arm 38 is connected to the respective depending section 34 by a transverse pivot pin 41 while the lower parts of the front arms 38 are pivotally mounted to the main frame 14 by spaced, coaxial transverse pivot pins 42 and 43.

The rearmost arm 39 of each pair is pivotally mounted to the respective depending sections 34 and the main frame 14 by additional pivot pins 44, 45 which extand substantially parallel to the pins 41, 42 and 43.

The mounting of the respective arms 38, 39 and the location of the respective mounting pins results in a line containing the axes of the pivotal connection of one arm 38 intersecting a line containing the axes of the pivotal connection of the other arm 39 at a point which is instantaneously located at 47 (see Figures 4 to 6) and which is preferably at or near the ground surface 49. This point 47 comprises a virtual hinge point about which the arms 38, 39 instantaneously pivot and which, therefore, the draught forces and the resistant forces act.

When a draught force is applied to the draught WVO 86/05653 PC/\8/08 rame 16 in "he forward m~oving d4 -acti.on, thQe arm arran~ Meant causes the main frame 14 to act a3 if it were fluxiLiA%' connected to the draughe frame 16 by a hinge located at the instantaneous virtual hinge point 47. By appropriat- ;dimensioning and angulation of the armo 38 and 39, the instantaneous virtual hinge point 47 may be caused to at a desired plane on or beneath the ground surface 41), preferably at the plane of the resultant soil rosiotant forces acting upon the tines 22. By locating the instant- ~janeous virtual hinge point 47 on this plane, the resultant rotative moment of the working frame is virtually eliminat(_J and the cultivator 12 acts as though it is being drawn by draught forces acting through the instantaneous virtualU hinge point 47.

Referring to Figures 4 to 6, by having front wheelo 23 and rear wheels 21, the main frame 14, and any attached side frames 15, are able to follow soil undulations without significant changes in depth of penetration between 0.tincs 22 at the front and rear of the main frame 14. This, therefore, enables very accurate control of the depth of penetration of the cultivator tines 22 which is vitally important in tillage and sowing operations, particularly with new varieties of grains which have been recently developed and which must be sown at precise depths to provide optimum development. As will be seen in Figure if 4, when the cultivator 12 is being drawn across level ground, the virtual hinge point 47 is at or near the depth of penetration of the tines 22. On rising ground, as shown in Figure 5, the relative movement between the draught frame 16 and the main frame 14 causes relative movement of the arms 38 and 39 which varies the location of the instantaneous virtual hinge point 47 whilst maintaining the substantially constant depth of penetration of the tines 22. Similarly, as shown in Figure 6, when the ground falls away in front of the cultivator 12, the instantaneous virtual hinge point 47 moves rearwardly due to relative movement of the draught frame 16 and the main frame 14 WO 86/05653 causing relative movement of the pal.rj o 1 A L-3 -1 :his relative movement enables the depth o. penetrton to be maintained substantially constant.

It will be seen from Figures 1 and 2 that the of arms 38 and 39 are supported in a cantilever fashicn from the depending sections 34. A pair of hydraulic cylinders 51 mounted to the rear end of the main frame 14 each have a forwardly extending piston rod 52 the front end of which is carried in a lost motion olot 53. Actuati:..

i of the hydraulic cylinders 51 pivots the main frame 14 to the position illustrated in dashed lines in Figure 3 whereby the working tools i.e. the cultivator tines 22, are lifted from the ground for transportation. The posit-.n of the pairs o! arms 38 and 39 relative to the depending sections 34 facilitates the relative movement of the main frame 14 to the position shown.

Referring to Figure 7 there is shown a modified form of cultivator in accordance with the present invention.

In this embodiment, a curved guide 55 is mounded on the main frame 14, the curvature of the guide preferably being arcuate with a radius The draught frame 16 carries at the rear end of the depending section 34 a pair of front rollers 56 which engage the front surface of the curved guide 55, and a rear roller 57 to engage a rear guide surface 58.

The instantaneous centre of the front rollers 56 and rear roller 57 on the curved guide 55 becomes the point through which the draught forces are effectively applied to the main frame 14. This point is located on or close to the centre of curvature of the curved guide 55 or, if the curved guide is not arcuate, at the instantaneous centre of that part contacted by the rear roller 57. By appropriate design of the guide 55 and location of the rollers 56, 57, the instantaneous centre through which the draught and resistance forces act can be located on or adjacent the load plane.

It will be appreciated that as the relative positions V'0 86/0563 PCI/ WOMIS I to variati.on inl topography, tho rollur; 56, 57 il~ tho curved guide 55 maintaining tho 4Anu~ ponta the deoi.rd location.

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Claims (14)

1. A draught frame structur frame and a draw bar therefor bar having means for connecti equipment frame being supportec I with a rear end of the draw ba from a forward part of the e and second load transfer means a and resistance forces betwee equipment frame, said first and interacting to define an instc equipment frame and through wh Sf' °.draught and resistance forces ac i^ n are as follows: *e comprising an equipment a front end of the draw on to a prime mover, the i on front and rear wheels c extending over and spaced .quipment frame, and first irranged to transfer draught n the draw bar and the second load transfer means antaneous centre below the iich the resultant of the :t. 9 a a ii.,.

2. A draught frame structure according to claim 1 wherein the equipment frame comprises an agricultural implement having a working frame carrying ground working tools.

3. A draught frame structure according to claim 2 wherein said ground working tools comprise cultivator or plough shares.

4. A draught frame structure according to any one of claims 1 to 3 wherein said first load transfer means comprises a pair of first connecting link members connected by substantially co-axial transverse pivots to the draw bar, the first link members extending downwardly to connect pivotally with the equipment frame, and said second load transfer means comprises a pair of second connecting link members connected by substantially co-axial transverse pivots to the rear end of the draw bar, the second link members extending downwardly and forwardly to connect pivotally with the equipment frame, the first and second link members being angled relative to each other such that lines passing through the respective pivotal connections of the respective pairs of link members intersect below the equipment frame. -1 A draught claims to 4 w legs defining an to the prime mo upwardly and r overlying the equ

6. A draught wherein the upw Sportions of th 1 7. A draught claim 6 wherein *I pivotally connect

8. A draught S" claims 1 to 3 wh parts comprise one of the draw roller means mour defining said i frame, and the in the direction Strack correspondi

9. An agricul frame carrying the equipment fra the equipment fr S* two legs divergi terminating in r portions overlyi a pair of front the respective frame, the front from the rear er of rear links ea a respective fror U to the respectiv -12- frame structure according to any one of herein said draw bar comprises a pair of A-frame, the apex of which is connected ier and the free ends of the legs having earwardly extending rear end portions ipment frame. frame structure according to claim ardly and rearwardly extending rear leg e A-frame are substantially parallel. frame structure according to claim 5 or the respective pairs of link members are ed to a front part of the equipment frame. frame structure according to any one of erein said first and second load transfer a curved track member mounted on either bar or the equipment frame and interacting ited on the other, the curved track member nstantaneous centre below the equipment roller means transmitting draught forces of the instantaneous radius of said curved ng to the roller means position. tural implement comprising an equipment ground working tools, wheels supporting .me above the ground, a draw bar to connect ame to a prime mover, the draw bar having ng rearwardly from the front thereof and spaced, substantially parallel rear end ng a front part of the equipment frame, links connected by transverse pivots to rear end portions and to the equipment links extending downwardly and rearwardly id portions of the draw bar legs, a pair ch of which is longitudinally spaced from it link and connected by transverse pivots e rear end portions and to the equipment frame, the rear 1 from the rear end I -2 -1 3- inks extending downwardly and forwardly ortions. 00 0 0 S 0 00 o 0* .000 0 0 o 00 0 0 0 An implement according to claim 9 wnerein iines connecting the pi-,',ts of each pair of front and rear links intersect at or adjacent ground level.

11. An implement according to claim 9 or claim 10 wherein said ground working tools comprise cultivator or plough shares.

12. An implement according to any one of claims 9 to 11 wherein said equipment frame is supported by front and rear wheels which are mounted on pivotal supports enabling the height of the equipment frame to be adjusted.

13. An implement according to any one of claims 9 to 12 wherein each said front link is of an inverted "Y" shape, and the pivotal connection to the equipment frame comprises spaced coaxial pivot pins for each part of the link.

14. PAn implement according to any one of claims 9 to 13 wherein all of said links are mounted by cantilevered pivot pins extending from the rear end portions of the draw bar and from the equipment frame, and hydraulic cylinder means attached to the equipment frame is connected by a lost motion connection to the draw bar, the equipment frame pivoting about the cantilevered pivot pins during actuation of the hydraulic cylinder means thereby lifting the equipment frame relative to the draw bar. An implement according to any one of claims 9 to 14 wherein said substantially parallel rear end portions are interconnected by a transverse tubular member disposed in front of the main frame, and the draw bar legs are connected to the rear end portions by a pair of locating pins. *0 OS 0 0 0 0 __I

16. An implement a wherein secondary of the main frame.

17. A cultivator co cultivator tines, he height of the frame rearwardly extending to the rear ends of substantially paral longitudinally spaced frame member, the a the respective fram relative longitudina S' arms being pivoted S, each pair instantane Swhich is on or adjacei *18. A cultivator ac of each arm is fixed.

19. A cultivator su with reference to the DATED this 9th day of ALFARM AUSTRALIA LTD. -14- ccording to any one of claims 9 to Sframes are hinged to either side mprising a wheeled main frame carrying ight adjustment means to adjust the a draw bar comprising a pair of diverging legs, a draw frame connected the legs and including two spaced lel frame members, a pair of arms extending downwardly from each rms of each pair being connected to e member by pivot means permitting 1 movement, the lower ends of the to the main frame, and the arms of ously defining an angle the apex of nt the ground surface. cording to claim 17 wherein the length bstantially as hereinbefore described accompanying drawings. October, 1989. c r: 'YS MVELRBALCI SOJ2TRALA