GB2043419A

GB2043419A - An agricultural drill

Info

Publication number: GB2043419A
Application number: GB8005269A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-02-17
Filing date: 1980-02-15
Publication date: 1980-10-08
Also published as: GB2043419B

Abstract

An agricultural drill for seeds and fertilizer, which maintains an even ground-engaging pressure on all the groove-forming discs (8) and tines (9), has a frame (1) which pivotally supports two transverse, spaced-apart rows of arms (7) carrying respective discs (8) and tines (9). The arms (7) of each row are resiliently connected to a respective transverse beam (10), the beams being pivotally interconnected by a yoke (12) which is pivoted to the frame (1), such that an upward movement of the leading row of arms (7), on passing over a large undulation, causes the yoke (12) to pivot and keep the other row or arms in engagement with the ground. The resilient connections of the arms (7) comprise springs (11) which yield when the drill passes over small undulations. <IMAGE>

Description

SPECIFICATION An agricultural drill The present invention relates to agricultural drills.

In particular, the invention concerns an agricultural drill of the type comprising a frame which is adapted to be towed, in use, by an agricultural vehicle and has at least one supporting wheel or roller, a plurality of groundengaging, groove-forming members, and a container having means for introducing seeds and/or fertilizer into grooves formed in the ground by the groove-forming members as the drill advances over the ground.

Known agricultural drills generally have at least two parallel rows of groove-forming members which are carried on the frame so as to be transverse the direction of advance of the latter. The groove-forming members are spaced apart in each row, and the members of adjacent rows are staggered laterally relative to each other, so that each groove-forming member forms a separate groove in the direction of advance.

In use, the drill is towed by an agricultural vehicle, usually a tractor, so that the grooveforming members, such as discs or tines, cut a plurality of parallel grooves in the ground into which seeds and/or fertilizer are introduced. In order to function efficiently all the groove-forming members must penetrate the ground and the depth of penetration of the members must be kept within strict limits.

The penetration, or working depth, of the groove-forming members will vary according to the requirements of the crop being planted; typical working depths are of the order of 3 to 6 centimetres, with an acceptable tolerance of 1.5 centimetres. A constant working depth is ensured by maintaining an even pressure on all the the groove-forming members.

When an agricultural drill is used on even ground there is little difficulty in ensuring an even pressure but when the drill is used on an undulating ground surface, Such as rough moorland pasture or arable headlands, many of the groove-forming members will be out of the ground at any one time. For example, when the tractor climbs an incline, the forward groove-forming members will be lifted out of the ground as the height above the ground of the leading end of the frame increases, and as the leading end of the frame breasts the top of the incline the rear members will be lifted.

In known agricultural drills attempts have been made to overcome this difficulty by pivoting one end of each groove forming member to the frame and resiliently connecting the members, adjacent their other ends, to a transverse beam, which is located above and between each row of grqove-forming members, by means of an inclined helical coil spring with a coaxial supporting rod. This arrangement provides an independent shock absorber for each groove-forming member thereby enabling the member follow the undu lation of the ground surface.

In this arrangement the transverse beam is common to two rows of groove forming mem bers. This is not satisfactory for all conditions of use, however, since the inclination of the spring reduces the permitted vertical movement of the groove-forming members relative to the frame to less than that necessary when the drill is used on very uneven ground, particularly moorland pasture. Moreover, this arrangement is not suitable when the grooveforming members comprise tines, since the close spacing of the rows, necessary to keep the inclination of the springs within acceptable limits, renders the tines susceptible to clogging by material lifted by the leading tines. In this case, the drill tends to act as a rake. Furthermore, due to the independent springing of each groove-forming member, it is difficult to maintain an even pressure on all the members.

The object of the present invention is to provide an agricultural drill of the aforesaid type which can compensate for the large undulations of the ground surface associated with rough pastures or arable headlands while maintaining an even pressure on all the groove-forming members, thus allowing the drill to "hug" the ground contours, and in which there is sufficient spacing between the rows of groove-forming members to permit the use of tines, rather than discs as in the known agricultural drills used previous, so that the drill is suitable for planting- grass seed in rough moorland pastures and the like, as well as conventional or direct drilling.

According to the present invention there is provided an agricultural drill of the aforesaid type, in which each groove-forming member is carried by a respective arm pivoted at one end to the frame to form two parallel rows of spaced apart said members, each row being transverse the direction of advance of the drill, each arm having a resilient connection to a transverse beam element situated above said row, the beam elements of the two rows being interconnected by means of at least one yoke supported by the frame for angular movement relative thereto.

In one embodiment, the beams are pivotally interconnected at each of their ends by respective yoke which may be pivoted to an adjacent side of the frame about a transverse axis intermediate the beams, or which may be supported on the frame by elastomeric bushes for "floating" movement relative to the frame.

In preferred embodiments, however, the beams are pivotally interconnected by a single yoke intermediate their ends, the yoke being pivotally supported on the frame intermediate the beams. Preferably, the beams are pivotally connected to the yoke for movement about longitudinal axes, and the yoke is pivoted to the frame for movement relative thereto about a transverse axis.

The resilient connection between each arm and the respective beam may comprise a helical coil spring, or a shock absorber, which is attached to the free end of the arm and is pivoted to the beam about a transverse axis.

Preferably, the arm is articulated intermediate its ends to form two portions, each portion having a respective coil spring which is pivoted to a respective end of a rocker member pivoted to the beam about a transverse axis.

The rocker member may comprise a single element extending transversely beneath the beam, but preferably comprises a plurality of rocker bars each located above a respective arm.

The groove-forming member carried by each arm may comprise a disc, tine, share, or the like, but in the preferred embodiment comprises a disc and a tine, the latter being carried adjacent the free end of the arm.

The invention will now be more particularly described, by way of example, with reference to the accompanying, purely diagrammatic drawings, in which: Figure 1 is a side view of an agricultural drill according to one embodiment of the present invention; Figure 2 is a side view, on an enlarged scale, of a part of the drill of Fig. 1; Figure 3 is a perspective view of the part shown in Fig. 2; Figure 4 is a side view, similar to Fig. 2, of a part of an agricultural drill according to a second embodiment of the invention, and Figure 5 is a plan view of the part shown in Fig. 4.

The same reference numerals are used throughout the drawing to indicate the same corresponding component parts.

Referring now to the drawings, there is shown an agricultural drill which comprises a frame 1 having a draw-bar 2 pivotally attached to its leading end, and a pair of supporting wheels 3 (one of which is shown) each carried by a respective arm 4 which is pivoted to a side portion of the frame 1. The draw-bar 2 is adapted for connection with a towing linkage if an agricultural vehicle, usually a tractor (not shown). The angular position of the frame 1 relative to the draw-bar 2, and of the wheel arm 4 relative to the frame can be adjusted by selectively operable hydraulic actuators 5, 6 respectively, which are connected with the hydraulic circuit of the tractor when the drill is in u.

A plurality of arms 7 (two of which are shown in the drawings) are each pivotally mounted at one end to transverse members 1 A of the frame 1. Each arm 7 carries a ground-engaging, groove- forming member comprising a disc 8 and an arcuately curved tine 9. The discs 8 are rotatably mounted on the arms 7 intermediate the ends thereof and the tines 9 are carried at the free ends of the arms 7. The pitch of the arm 7, that is, the angle of the arm relative to the frame 1, can be varied to alter the relative working depths of the disc 8 and tine 9 on the arm. When the drill is in use the tines 9 curve towards the direction of advance of the drill, indicated by arrow A.

As shown in Fig. 3, the arms 7 are mounted transverse the direction of advance of the drill so as to form two parallel rows spaced apart in the direction of advance A.

The arms 7 are spaced apart in each row, and the arms of adjacent rows are staggered relative to each other so that each ground-engaging member forms a separate groove in the ground in the direction of advance A of the drill.

Each arm 7 of each respective row is resiliently connected, adjacent its free (trailing) end, to a transverse beam 10 which is situated above the row. The resilient connections are formed by respective helical coil springs 11, each of which is pivoted to the respective beam 10 and has a coaxial supporting rod which is slidable in a hole formed in the beam 10. The beams 10 above the two rows are pivotally interconnected at each of their ends by a respective yoke 1 2 which is, in turn, pivoted to the frame 1 intermediate the rows to allow angular movement relative to the frame about a transverse axis, that is, an axis perpendicular to the direction of advance A of the drill. The yoke pivot 13, as shown in Fig.

2, is adjustable vertically, in this case by a screw adjuster, with respect to the frame 1 to permit a greater or lesser amount of angular movement of the arm 7 and to increase or decrease the pitch of the arm 7.

In the embodiment shown in Figs. 4 and 5, the transverse beams 10 are connected, by respective pivot joints 1 5A intermediate their ends, to a single yoke 1 2 for angular move ment about longitudinal axes. In turn, the yoke 1 2 is connected, by a pivot joint 1 SB intermediate the beams 10, to a longitudi nally-extending frame member 14 for angular movement relative thereto about a transverse axis, thereby allowing the beams 10 to make angular movements relative to the frame 1 about both longitudinal and transverse axes.

In this example, there are two yokes 12 (each with respective beams 10) disposed symmetri cally on each side of the longitudinal axis X-X of the frame 1, enabling the drill to be used on steeply undulating ground. The position of the yoke pivot joint 1 SB can be adjusted vertically relative to the frame member 14 in a similar manner to the pivot 1 3 described above. In an alternative example, the yoke 1 2 may have a universal pivotal connection to the frame member 14, instead of the joint 1 SB.

As shown in Fig. 4, each arm 7 is articu lated intermediate its ends to form two portions 7A, 7B. The first portion 7A of the arm 7 is pivoted to a transverse member 1 A of the frame and rotatably supports a disc 8, while the second portion 7B carries a tine 9 adjacent its free end. Each arm portion 7A, 7B is resiliently connected to the respective overhead transverse beam 10 by a respective helical coil sping 11 which is attached at one end adjacent the trailing end of the respective arm portion, and pivoted at its other end to a respective end of a rocker bar 1 6 situated above each arm 7 and pivoted to the beam 10 about a transverse axis.

In this embodiment the articulation of each arm 7, and the resilient connection of each arm portion 7A, 7B to the rocker bar 1 6 ensures that, in use of the drill, the tine 9 will stay in the ground until it encounters a ground undulation rather than being lifted with the disc 8, when the latter encounters the undulation as in the embodiment previously described. This allows seeds to be planted right up to an undulation when operating on rough ground.

As shown in Fig. 1, the frame 1 also carries seed and fertilizer hoppers 1 7 of known type which have a plurality of tubes 18, each connected from a metering outlet 1 9 on the respective hopper 1 7 to the rear of a respective hopper 1 7 to the rear of a respective tine 9, for introducing seeds and fertilizer into the groove formed by the tines 9 as the drill advances over the ground.

A reservoir 20 for water, or liquid chemicals, such as fertilizer, pesticide or herbicide, is mounted on the frame 1, and has a pump control tap 20A which is operable from the tractor. Liquid discharge outlets 21 from the reservoir 20 are arranged so as to discharge onto the ground in front of the advancing discs 8 and tines 9. Outlets from the reservoir 20 could alternatively, or in addition, be mounted at the rear of the frame 1.

When the agricultural drill is in use the discs 8 cut slots in the ground into which the tines 9 penetrate to form grooves. The tines 9 have readily replaceable shoes 9A to enable the dimensions of the grooves to be varied as desired. An even ground-engaging pressure is maintained by the springs 11. When the drill advances over a small undulation, the springs 11 act as shock absorbers for each arm 7, enabling individual discs 8 and tines 9 to "hug" the ground. When the drill advances over large undulations which are transverse the direction of advance A, the leading row of discs 8 and tines 9 will compress the respective springs 11 sufficiently to cause the yokes 1 2 to pivot about the transverse axis, thereby keeping the trailing row in engagement with the ground while maintaining an even pressure on all the discs 8 and tines 9.

In the embodiment shown in Figs. 4 and 5, the transverse beams 10 can also pivot about a longitudinal axis, enabling the drill to cope with large undulations which are parallel to the direction of advance A. In a similar way to that described above, the pressure exerted by the discs 8 and tines 9 on one side of the pivot joint 1 5A of the beam 10 will compress their respective springs 11 sufficiently to cause pivoting of the beam 10, thereby keeping the discs 8 and tines 9 on the other side of the joint engagement with the ground, whilst exerting an even pressure on all the discs and tines.This arrangement renders the drill more versatile, and is particularly useful when drilling around a rough field boundary, since the beams 10 and yoke 1 2 on one side of the longitudinal axis X-X can pivot to allow drilling over the undulations, while the beams 10 and yoke 1 2 on the other side of the axis remain parallel to the more even surface of the field itself.

At the end of a drilling operation the discs 8 and tines 9 are lifted out of the ground by lowering and supporting wheels 3 under the action of the hydraulic actuators 6. During use, the actuators 6 can be used to increase the pressure or working depths of the discs 8 and tines 9 by lowering or raising the frame 1 relative to the wheels 3.

An agricultural drill constructed in the manner described above can be used on very uneven ground, since the angular movement of the beams 10 and yokes 1 2 relative to the frame 1 will prevent the discs 8 and tines 9 from being lifted out of the ground, even when the frame 1 is steeply inclined relative to the ground, such as when climbing an incline or when drilling in a rough field boundary.

Claims

1. An agricultural drill comprising a frame which is adapted to be towed, in use, by an agricultural vehicle and has at least one supporting wheel or roller, a plurality of groundengaging, groove-forming members, and a container having means for introducing seeds and/or fertilizer into grooves formed in the ground by the groove-forming members as the seed drill advances over the ground, in which each groove-forming member is carried by a respective arm pivoted at one end to the frame to form two parallel rows of spaced apart said members, each row being transverse the direction of advance of the drill, each arm having a resilient connection to a transverse beam element situated above said row, the beam elements of the two rows being interconnected by means of at least one yoke supported by the frame for angular movement relative thereto.

2. An agricultural drill as claimed in Claim 1, in which the beams are pivotally interconnected at each of their ends by a respective yoke which is pivoted to an adjacent side of the frame about a transverse axis intermediate the beams.

3. An agricultural drill as claimed in Claim 1, in which the beams are interconnected by a yoke intermediate their ends, the yoke being pivotally supported on the frame intermediate the beams.

4. An agricultural drill as claimed in Claim 3, in which the transverse beams are pivotally connected to the yoke for movement about longitudinal axes, and the yoke is pivoted to the frame for movement relative thereto about a transverse axis.

5. An agricultural drill as claimed in Claim 2, Claim 3 or Claim 4, in which the position of the yoke pivot axis is adjustable vertically with respect to the frame.

6. An agricultural drill as claimed in Claim 1 in which each arm is articulated intermediate its ends to form two portions, each having respective resilient connection means pivoted to a respective end of a rocker member which is pivoted to the beam about a transverse axis.

7. An agricultural drill as claimed in Claim 6, in which the resilient connection means comprise a helical coil spring.

8. An agricultural drill as claimed in Claim 6, in which the rocker member comprises a plurality of rocker bars each located above a respective arm.

9. An agricultural drill as claimed in Claim 1, in which each groove-forming member comprises a disc and a tine.

10. An agricultural drill as claimed in Claim 6 and Claim 9, in which the disc is carried on the portion of the arm which, in use, is forward of the articulation axis of the arm, and the tine is carried on the portion of the arm to the rear of the articulation axis.

11. An agricultural drill as claimed in Claim 9 or Claim 10, in which the pitch of each arm is adjustable to vary the depth of penetration of the tine and disc relative to each other.

12. An agricultural drill as claimed in Claim 1, in which a draw-bar is pivotally attached to the frame about a horizontal axis for attachment to the towing vehicle, and in which jacking means interconnect said drawbar and said frame, the jacking means being selectively operable to pivot said frame relative to said draw-bar.

1 3. An agricultural drill as claimed in Claim 1, in which a supporting wheel is attached to each side of said frame by a respective arm which is pivoted at one end to the frame about a horizontal axis, the arms being adjustable about said axis by respective selectively operable jacking means.

14. An agricultural drill as claimed in Claim 1, in which said container comprises a hopper and said introducing means comprise a plurality of tubes each connected at one end to a metering outlet of said hopper and at the other end to the rear of a respective tine.

1 5. An agricultural drill as claimed in any of the preceding claims, in which the frame supports a liquid reservoir connected to a plurality of liquid discharge outlets arranged in a row transverse the direction of advance of the drill.

16. An agricultural drill as herein described with reference to, and as shown in, the accompanying drawings.