"Tyne Assembly and Tyne"

THIS INVENTION relates to a tyne assembly, and tyne for use with agricultural implements and which have particular utility in cultivating soil for agricultural purposes.

In recent times, there has been a growing awareness in the community and particularly amongst scientists and agriculturalists alike of the importance of soil conservation in the light of the potentially catastrophic effects of soil erosion caused by current cultivating and harvesting techniques employed in the farming industry. It has been mooted that the principal reason for soil erosion is the repeated disturbance of the top soil arising from the use of current cultivating techniques, causing the loss of nutrients and essential organic elements from the soil following exposure of the subsoil to the open environment and repeated harvesting of crops upon the same area of land.

Indeed, with the increased availability of chemical additives and fertilisers for the soil and the pressures of increased productivity as a result of the competitive market place and relatively harsh economical factors affecting today's farmer-,— increased emphasis is being provided on maximising the yield from the soil with little or no regard being had to the necessity of soil conservation. Accordingly, it is believed that soil erosion and the long term effects of the same on the environment is the number one problem facing agricultural producers of the world due to the potential of this problem transforming an entire fertile continent to an arid wasteland.

Accordingly, it is an object of the present invention to provide for improved cultivating of the soil which minimises disturbance of the top soil so as to mitigate soil erosion problems resulting therefrom.

It is a preferred object of the invention to provide a tyne assembly incorporating a stump jump facility which fulfils the aims of the preceding object.

It is another preferred object of the invention to provide a tyne which can be used in conjunction with the tyne assembly referred to in the preceding objects of the invention.

In accordance with one aspect of the— resent invention, there is provided a stump jump tyne assembly for an agricultural implement comprising a tyne support for mounting to an agricultural implement above the ground, a tyne to be pendently mounted to said tyne support for engaging the ground, and biasing means to bias said tyne towards a ground engaging position; wherein said tyne is adapted to move rearwardly and upwardly relative to said tyne support upon encountering an opposing substantially unrelenting force greater than the biasing force of said biasing means, whilst maintaining its angular disposition relative to the ground for substantially the duration of its engagement with the ground.

Preferably, said tyne support is provided with a track extending longitudinally from an anterior position to a rearward position of said tyne support and said tyne is provided with a carriage for moving along said track, whereby when said tyne support is mounted to said implement, the longitudinal extent of said track is

obliquely disposed relative to the ground and said anterior position is at a depressed location relative to said rearward position, said carriage being disposed towards said anterior position when said tyne is at said ground engaging position and said carriage being disposed towards said rearward position when said tyne is not at said ground engaging position.

Preferably, said tyne is capable of changing its angular disposition relative to the ground when said carriage is disposed at said rearward position to facilitate clearing any obstacle causing said opposing unrelenting force.

Preferably, said carriage is provided with roller means to facilitate moving along said track, said roller means engaging either side of said track.

Preferably, the upper side of said track is provided with a recess at said rearward position to receive the rear of said roller means when said carriage is disposed at said rearward position, thereby enabling said tyne to change its angular disposition relative to the ground.

Preferably, said tyne includes a ground engaging portion which is detachably connected to said carriage.

Alternatively said carriage may be integrally formed with said ground engaging portion.

In accordance with another aspect of the present invention, there is provided a tyne for an agricultural implement comprising a shank having a ground engaging portion towards one end thereof and a point mounted to said one end for cultivating the subsoil of the ground, said shank being elongated in the intended direction of

travel of said implement and having an acuate anterior edge to facilitate penetration through the ground in said direction whilst mitigating disturbance of the topsoil of said ground.

Preferably, said point has a truncated nose terminating in approximate alignment with the anterior edge of said shank, and laterally extending wings either side of said shank.

Preferably, said nose extends rectilineally in opposed lateral directions of said shank.

Preferably, said point is detachably mounted to said one end of said shank and has an expansive portion, which is substantially coplanar, and marginal edges around the periphery thereof, which are depressed.

Preferably, said one end of the shank is provided with a transversely extending mounting wing disposed towards the rear end of said shank and a forwardly extending mounting hook disposed towards the anterior end of said shank, whereby said mounting wing is substantially coextensive with the corresponding transverse extent of said expansive portion of said point to provide lateral stability to said point, and said mounting hook is adapted to co-operate with a correspondingly disposed aperture provided in said point to positively engage and connect said point to said one end when the rear end of said point is passed over said mounting wing sufficiently for the rear marginal edge thereof to clear the rear end of said mounting wing.

In accordance with a further aspect of the present invention, there is provided a point for a tyne of the kind described in the preceding aspect of the invention.

In accordance with another aspect of the present invention, there is provided a shank for a tyne of the kind defined in the penultimate aspect of the invention.

The invention will be better understood in the light of the following description of several specific embodiments thereof. The description is made with reference to the accompanying drawings wherein:-

Figure 1 is a side elevation of the stump jump tyne assembly with the tyne thereof disposed in a ground engaging position in accordance with the first embodiment;

Figure 2 is a similar view to ^" Figure 1 but showing the tyne disposed in a maximally rearward position to clear the ground where the angular disposition of the tyne has been changed;

Figure 3 is a sectional front elevation of the tyne assembly having the tyne in a ground engaging -position and showing a tyne having a carriage integrally formed therewith;

Figure 1' is a section front elevation similar to figure 3 of the drawings of the tyne assembly in accordance with the second embodiment;

Figure 1' ' shows a front perspective view of the shank of the tyne in accordance with the third embodiment;

Figure 2 ' ' shows the ground engaging portion of the shank shown at Figure 1 ' ' fitted with a point of the kind described in the third embodiment;

Figure 3' ' is a plan view of Figure 2' ' ; and

Figure 4' ' is a side elevation of the lower path of Figure 2' ' .

The first embodiment is directed towards a stump jump tyne assembly 11 shown at Figures 1, 2 and 3 of the drawings, generally comprising a tyne support 13 a tyne 15 and biasing means 17.

The tyne support 13 comprises a housing formed of a pair of C-shaped box channel members 19a and 19b, upper and lower pairs of wear strips 21 and 23 respectively and a pair of end plates 25.

The box channel members 19 each have one of the wear strips of both of the upper and lower pairs welded along the outer face 27 of the interconnecting web portion thereof so that the wear strips extend longitudinally along the web portion at the upper and lower edges thereof. Thus one channel member 19a is provided with an upper and a lower wear strip 21a and 23a, respectively and the other channel member 19b is provided with an upper and a lower wear strip 21b and 23b, respectively.

The wear strips 21 and 23 of each channel member 19 are sufficiently spaced apart to define respective sides of a track 29 of the tyne support 13 within the housing.

The channel members 19 and their corresponding upper and lower wear strips 21 and 23 are spaced apart in

symmetrical arrangement about a central longitudinal plane 30 and are fixed in this relationship by the provision of the end plates 25. Moreover, the end plates 25 are connected to integral end flanges 31 at the respective ends of the channel members 19a and 19b by nut and bolt assemblies 33. Thus the corresponding anterior end of the channel members and wear strips is covered by one end plate 25a and the corresponding rearward end of the channel members is covered by the other end plate 25b. In this manner, the channel members 19, upper and lower wear strips 21 and 23 respectively and the end plates 25 combine to form the housing and define the track 29. Consequently, the track 29 extends longitudinally centrally of the housing from an anterior position covered by the end plate 25a to a rearward position covered by the end plate 25b.

The tyne 15 generally comprises a carriage 34 and a ground engaging portion 35. The carriage 34 may either be integrally formed with the upper end of the shank 36 of the tyne as shown at Figure 3 of the drawings, or alternatively be formed discretely from the ground engaging portion 35 as shown at Figures 1 and 2 of the drawings to enable attachment and replacement of the ground engaging portion 35 as a result of wear or damage to the same.

The carriage 34 is provided with roller means in the form of a pair of bearing arrangements 37 disposed on each side of the carriage, each bearing arrangement comprising a bearing 38 having an outer track engaging surface and a journal 39 integrally formed with the carriage 34. The bearing arrangements 37 on each side of the carriage are transversely spaced apart in parallel arrangement so that the central axis of each is substantially orthogonal to

the longitudinal plane 30 of the tyne- support. Furthermore, each pair of bearing arrangements 37 extends outwardly from the carriage in opposed axial alignment so that an anterior bearing arrangement 37a of one pair is oppositely aligned with the corresponding anterior bearing arrangement 37a of the other pair, as shown in the drawings, and similarly the posterior bearing arrangement 37b of the one pair is oppositely aligned with the corresponding posterior bearing arrangement 37b of the other pair.

The bearings 38 are of essentially the same diameter which is less than the space between the upper and lower wear strips 21 and 23, respectively, of the tyne support to enable the roller means of the carriage to be accommodated within the track 29 of the tyne support in the manner shown in the drawings. The spaced apart parallel and co- planar alignment of each bearing arrangement, substantially orthogonal to the longitudinal plane 30 of the tyne support, enables the tyne to be pendently mounted within the tyne support and extend substantially orthogonally therefrom with respect to the longitudinal axis of the track 29.

The transverse extent of the carriage 34 is less than the spacing between adjacent upper wear strips 21a and 21b, and lower wear strips 23a and 23b respectively. Additionally, the transverse extent of each corresponding bearing arrangement 37 together with the transverse extent of the carriage, is less than the corresponding transverse extent of the track to enable accommodation of the bearing arrangements and carriage within the confines of the track and consequently enable axial movement of the carriage along the track by the bearings 38 running between corresponding upper and lower wear strips.

As a result of the bearings 38,. having the same diameter, the tyne can maintain its angular disposition relative to the carriage for the duration of movement of the bearings 38 along the wear strips of the track.

A recess 41 is provided proximate the rearward position of the track adjacent to each upper wear strip 21. The recess is of sufficient size to accommodate the entire diameter of each pair of rear bearings 38b so that when the rear bearings 38b move to a position opposite the opening of the recess 41, the angular disposition of the tyne can be altered in response to a continuing upward, force whereby the pair of rear bearings 38b may be fully accommodated within the recess 41 allowing the tyne to pivot rearwardly about the anterior bearings 38a so as to clear an obstacle or the like causing the angular movement of the tyne.

In the case of the discretely formed carriage 33, the lower end of the carriage is provided with a socket in which to receive the shank of the ground engaging portion 35 of the tyne. A pair of apertures extend transversely through opposite sides of the socket to enable corresponding apertures provided in the shank of the ground engaging portion of the tyne to be aligned therewith and so be fixed into position by the provision of fasteners such as nuts and bolts 43.

The upper end of the rear of the carriage, in order to enable pivoting about the anterior bearings 38a when the pair of rear bearings 38b is disposed at the rearward location of the track, is tapered to define an acute included angle between the upper end 45 and the anterior face of the carriage.

The biasing means 17 comprises a tension spring disposed between the carriage 33 and the tyne support 13. As shown at Figures 1 and 2 of the drawings, one end of the spring is fixedly mounted to the carriage towards the rearward end thereof and the other end is fixedly mounted to a depending projection 49 from the front plate 25a of the housing. The spring biases the carriage, and hence the tyne, towards an anterior position relative to the track 29 whilst permitting movement of the carriage, and hence the tyne, along the track in response to an opposing force. Consequently, a biasing force is applied to oppose the opposing force and keep the ground engaging portion 35 of the tyne in contact with .the ground. However, in the event of the tyne encountering a substantially unrelenting opposing force, greater than the biasing force of the spring, the carriage will travel along the track until the pair of rear bearings 38b enter the recess 41 allowing the tyne to pivot, thereby altering its angular disposition in order to clear the obstacle providing the unrelenting opposing force.

In operation, the tyne support is mounted to a cross bar 51 of an agricultural implement by means of a U-bolt fastener 53. The cross member 51, as shown at Figures 1 and 2 of the drawings, is of rectangular hollow section and is disposed upon the agricultural implement with the sides thereof offset to the horizontal so that the carriage 13 can be fastened to the lower side 55 of the cross member at an oblique angle to the horizontal. In this manner the tyne 15 can be disposed at an acute included angle to the ground for cultivating purposes. The U-bolt fastener 53 conse»quently is disposed to circumscribe the remaining sides of the cross member and project through corresponding apertures provided in the

outwardly extending upper flanges of the channel members 19, in the manner shown at Figure 3 of the drawings, to receive bolts 57 which can be tightened to clamp the upper side of the housing to the cross member 51.

The principal advantage provided by the present embodiment is that the angular disposition of the tyne relative to the ground can be maintained constant for the duration that the tyne is in engagement with the ground. Thus, upon encountering an obstacle, the tyne can still retract instead of changing its angular disposition with respect to the ground by pivoting about a fixed point, as is the case in conventional stump jump tyne designs, the angular disposition of the tyne relative to the ground is maintained constant until such time as the point of the tyne disengages the ground. Obviously, the length of the track 29, depth of the recess 41, angular disposition of the track relative to the horizontal and elevation of the cross member 51 relative to the ground, all need to be specially determined for the particular cultivating operation employed to enable the disengagement of the point from the ground to coincide with the rear bearings 38b entering the recess 41. By maintaining the constant angular disposition of the tyne relative to the ground for the duration of its engagement with the ground inordinate disturbance of the top soil which arises from changing the angular disposition of the tyne relative to the ground during its engagement therewith, as is the case in conventional stump jump tyne designs, is mitigated.

The second embodiment is substantially the same as the previous embodiment except that the arrangement of the wear strips 21 of the track and the outer track engaging surface of the bearing arrangements is improved to provide greater stability of the tyne against lateral forces.

Moreover, as shown at figure 1' of the drawings, the roller engaging surfaces 71 of the upper wear strips 21a and 21b and of the lower wear strips 23a and 23b are obliquely angled transversely of the tyne support 13 opposite to one another to form upper and lower grooves having their apices 73 centrally disposed of the track 29 to be coincident with the space within which the upper of the shank 36 is disposed and hence in substantial vertical alignment with the central longitudinal plane of the tyne 15. Similarly, the outer tracking gauging surfaces 75 of the bearing arrangements 37 are frusto-conical to be substantially complimentary to the roller engaging surfaces 71 of the wear strips of the track. Consequently, the upper and lower sides of the track cooperate to maintain the position of the carriage centrally within the track and thus oppose lateral movement of the tyne and carriage to one lateral side or the other of the track.

The third embodiment is directed towards a tyne for an agricultural implement and is shown at Figures 1' ' , 2 ' ' , 3'' and 4'' of the drawings and which is particularly suited for use in conjunction with the tyne assembly described in the preceding embodiments. The tyne 101 essentially comprises a shank 103 having a ground engaging portion 103a and a point 105 mounted to the distal end of the ground engaging portion 103a.

The shank 103 is elongated in the intended direction of travel of the implement and has an acuate interior edge which extends rectilinearly along the full longitudinal extent of the ground engaging portion 103a of the shank. The transverse extent of the shank is relatively narrow compared to the longitudinal extent of the sides of the

shank, in the direction of intended travel, so that the acuate edge can penetrate through the ground when the tyne is drawn through the same by the agricultural implement, with minimal disturbance of the top soil of the ground. The distal end of the ground engaging portion of the shank is provided with a transversely extending mounting wing 109 and a forwardly extending mounting hook 111. The mounting wing 109 is welded towards the rear end of the distal end of the shank and has a lateral extent related to the corresponding lateral extent of the point 105, which shall be described in more detail later. The mounting hook 111 is disposed towards the anterior end of the distal end of the shank.

The point 105 is of generally triangular shape having a truncated nose 113 and laterally extending wings 115 which project outwardly either side of the ground engaging portion of the shank 103a. The point 105 has an expansive portion 117 which is co-planar and marginal edges 119 disposed around the periphery of the point and which are depressed. Accordingly, lateral marginal edges 119a are provided along each of the wings 115 of the point, and a rear marginal edge 119b is provided along the rear of the point.

An aperture 121 is provided along the central axis of the point within the region of the expansive portion 117 and is of prescribed size and location to receive the mounting hook 111 of the shank 103 soA:hat the hook may positively engage the anterior edge of the aperture by sliding the point rearwardly. Furthermore, the longitudinal extent of the mounting hook in the direction of intended travel of the tyne is commensurate to the distance of the expansive portion 117 between the anterior edge 121a of the aperture and the truncated nose 113, so that the

positioning of the aperture is such that upon achieving positive engagement between the point and the mounting hook, the truncated nose attains a position which is approximately aligned with the acuate edge 107 of the shank.

The longitudinal extent of the expansive portion 117 of the point in the intended direction of travel is commensurate with the longitudinal extent of the shank in the intended direction of travel thereof. Consequently, upon positive engagement of the point with the bottom of the shank, the rear of the expansive portion 117 attains an approximate alignment with the rear of the shank. The rear of the point 105 is also provided with a recess 123 so that when the point is slid rearwardly to positively engage the mounting hook 111, the rear of the point can pass over the mounting wing 109 and effectively lock into place when the rear marginal edges 119c clear the rear edge of the mounting wings 109.

It should be noted that the distal end of the ground engaging portion 103a of the shank is shaped so that the point is presented with an acute angle of attack relative to the horizontal with the acuate edge 107 terminating at a marginally depressed position relative to the rear edge of the shank while simultaneously allowing the shank to depend rearwardly from the agricultural implement. Consequently, the longitudinal extent of the acuate edge 107 is disposed at an oblique angle to the vertical.

The lateral extent of the mounting wings 109 is commensurate to the lateral extent of the expansive portion 117 of the point so that the mounting wings may provide lateral stability to the point when attached to the distal end of the ground engaging portion of the

shank. Furthermore, the marginal edges 119 of the point are depressed sufficiently to deflect soil away from the mounting wings 109 and mounting hook 111 along the underside of the point during travel of the tyne through the ground so that the soil does not directly impinge upon the same. In this manner the abrasive effect of the soil upon the mounting wings and hook is mitigated.

By adopting a tyne of the design described in this embodiment, minimal disturbance of the top soil is achieved whilst perfecting optimum tilling of the sub soil, thereby providing effective cultivation of the soil with improved conservation of the soil than is attainable with other types of known tyne design.

It should be appreciated that the scope of the present invention is not limited to the particular embodiments herein described.