GB2104761A

GB2104761A - Improvements in or relating to agricultural machinery

Info

Publication number: GB2104761A
Application number: GB08210829A
Authority: GB
Inventors: Andrew Dalton
Original assignee: Bamlett Ltd A C
Current assignee: Bamlett Ltd A C
Priority date: 1981-09-01
Filing date: 1982-04-14
Publication date: 1983-03-16
Also published as: GB8300447D0; AU8787582A; AU547970B2; GB2118414A; GB2104761B; FR2523805A1; NZ201738A; FR2517508A1

Abstract

A drill has a pivotally mounted coulter bar (3) which carries a coulter in the form of a narrow blade (6) to cut a slit in the ground. An elongate member (10) is pivotally connected to the coulter bar (3) and a member (16) is axially slidable on the elongate member. A hydraulic arrangement (23) is provided which, by means of levers and a rota table shaft drives the member 16 downwardly thus causing two springs (14, 15) located between the slidable member and the coulter bar around the elongate member (10) to be compressed thus driving the coulter (6) into the ground. One spring (14) is relatively long and of low strength, and the other spring (15) is relatively short but of higher strength. When the drill is operated the coulter forms a swirl of tilth behind it as it is drawn through the ground. Seeds dropped into this swirl of tilth come to rest entirely surrounded by tilth and are thus under optimum conditions for successful germination. <IMAGE>

Description

SPECIFICATION Improvements in or relating to agricultural machinery The present invention relates to agricultural machinery and more particularly relates to a drill.

Drills have been utilised for many years in connection with the sowing of seeds, and a conventional drill is adapted to be drawn by a tractor or similar arrangement. The drill includes a plurality of coulter bars which each carry a coulter which is adapted, when the coulter bar is in the operative position, to form a recesses in the ground. The drill also includes pipes through which seeds can be introduced to the recess in the ground.

It has been proposed to utilise a relatively blunt member as the coulter to form a recess in the ground but a drill provided with such a coulter can only be operated satisfactorily on recently ploughed and tilled ground. If the ground is hard the drill will not operate satisfactorily.

It has also been proposed to provide a drill having one or two discs to act as a coulter, the discs cutting a recess in the ground. Such a drill can, of course, be utilised on recently ploughed and tilled ground, and can also be utilised on unploughed land. However it is found that a substantial amount of power is required when utilising such a drill on unploughed land.

The present invention seeks to provide an improved drill, and the preferred embodiments of the invention are intended for use in planting grain crops in unploughed and untilled land.

Certain drills have been proposed before which utilise a narrow blade to cut a slit in the ground, but such blades have tended merely to form an open slit. Seeds have been deposited directly in the open slit, thus falling to the bottom of the slit.

In some cases the slit has subsequently been closed up. One disadvantage of such an arrangement is that the seed is located in an area of soil that is relatively compacted and thus any roots that the seed produces have to force their way through the compacted soil. Another embodiment of the present invention seeks to provide a drill which overcomes this particular disadvantage.

According to one aspect of this invention there is provided a drill comprising a pivotally mounted coulter bar carrying a coulter in the form of a narrow blade to cut a slit in the ground, and means for moving the coulter bar from a lowered operational position to an elevated non-operational position, said means including an elongate member connected to the coulter bar, a member which is axially slidable on the elongate member, and means for driving said slidable member, there being two resilient means mounted adjacent the elongate member which engage an abutment adjacent the coulter bar and which can engage said slidable member, the first resilient means being a relatively long means of low strength, and the other resilient means being a relatively short means of higher strength.

Preferably the coulter comprises a narrow blade which has a tungsten carbide cutting edge, so that the cutting edge will not rapidly be blunted during use of the drill. However the coulter is preferably releasably attached to the coulter bar so that if the cutting edge does become blunted, the coulter can readily be replaced by a fresh sharp coulter.

Preferably the first spring biases the slidable member against an adjustable stop provided at the end of the elongate member remote from the coulter bar when the coulter bar is in the elevated non-operational position. Preferably the adjustable stop comprises a screw threaded member provided on a screw threaded terminal portion of the elongate member.

Advantageously the slidable member is driven by a lever protruding from a rotatable shaft, there being means to rotate the shaft to cause a resultant movement of the coulter bar.

The drill in accordance with the invention may preferably include at least one pipe mounted on the coulter bar, the arrangement being such that, in operation of the drill, seeds can be passed through the pipe into the slit cut in the ground by the coulter. In a preferred embodiment a second pipe is also mounted on the coulter bar, and the arrangement is such that, in operation of the drill, seeds or fertilizer can be passed through the second pipe into the slit cutting the ground by the coulter.

A preferred drill in accordance with the invention comprises a plurality of said coulter bars and coulters.

Preferably one or both of said resilient means comprises springs. Alternatively one or both of said resilient means comprise resilient non-planar washers, such as beliville washers.

In another embodiment at least one of the resilient means comprises a gas strut.

According to another aspect of this invention there is provided a method of drilling comprising the steps of cutting a slit in the ground with a blade to form a swirl or tilth behind the blade, and introducing seeds into said tilth so that the seeds come to rest with tilth below them and tilth above them.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described by way of example with reference to the accompanying drawing which is a side elevational view of one coulter bar and the associated coulter, seed and fertilizer tubes, and driving member, of a drill in accordance with the invention.

Referring to the accompanying drawing it is to be understood that a preferred drill in accordance with the invention will include a plurality of coulter bars, the coulter bars being located side-by-side so that the coulter bars are parallel, the axes of the coulter bars extending in the direction of movement of the drill. Only one coulter bar is shown in the accompanying drawings, but it is to be understood that all the coulter bars will have a corresponding configuration.

Referring now to the drawing part of the frame 1 of a drill, which can for example be connected to a three point linkage so that the drill can readily be connected to a tractor or the like, pivotally supports, by means of a pivot 2, a coulter bar 3. At the end of the coulter bar remote from the pivotal linkage 2 there is a downwardly directed assembly 4 to which is releasably connected, by means of a nut and bolt 5, a coulter 6 which is in the form of a narrow sharp blade. The cutting edge 7 of the blade is formed of tungsten carbide. The downwardly directed assembly 4 also carries two pipes 8, 9 which can be connected, by appropriate tubes or conduits, to supply bins containing seed and/or fertilizer.

An apparatus is provided for moving the coulter bar 3 from the illustrated position, to a lowered operational position. This includes an elongate member 10, which in the example illustrated comprises a cylindrical rod. At its lower end the cylindrical rod 10 is connected pivotally to the coulter bar 3 by appropriate flanges 11 and a pivot pin 12. Adjacent the flanges 11 is an enlarged cylindrical member 13, which provides an upper abutment surface for two springs as will now be described.

Surrounding the elongate member 10 are two springs 1 4, 1 5 the lower ends which rest on the upper abutment surface formed by the cylindrical member 1 3. The first spring, 14 is a relatively long spring, that is to say it is longer than the spring 1 5, but also the spring 14 is a relatively weak spring, whereas the spring 1 5 is a relatively strong spring, that is to say the force required to compress the spring 14 by a predetermined amount is less than the force required to compress the spring 1 5 by the same predetermined amount.When the coulter bar 3 is in the elevated non-operational position shown in the accompanying drawing the spring 14 biasses a cylindrical member 16 that is slidably mounted on the elongate member 10 upwardly against a stop which is constituted by a nut 1 7 provided on a threaded end portion 1 8 of the elongate member 10. The slidable member is pivotally connected, by means of a pivot 19, to a lever 20 which is firmly mounted on a rotatable shaft 21. A further lever 22 is provided on the shaft 21, and this further lever is connected to a hydraulic cylinder driving arrangement 23.

When it is desired to move the coulter bar 3 from the elevated non-operational position as illustrated, to the lowered operational position the hydraulic cylinder 23 operates, the piston rod of that cylinder moving in the direction of the arrow 24. This causes the shaft 21 to rotate in the direction of the arrow 25, which causes the slidable member 1 6 to be driven downwardly in the direction of the arrow 26. The coulter bar thus pivots downwardly in the direction of the arrow 27, and the coulter 6 becomes inserted in the ground. There is, of course, certain resistance to continuing movement when the coulter 6 enters the ground, thus when the coulter 6 begins to enter the ground the spring 14 becomes compressed, and then the slidable member 1 6 contacts the upper part of the spring 15.As has been mentioned, this spring 1 5 is a relatively strong spring and thus sufficient force can be transmitted from the slidable member 1 6 to the coulter bar 3 through the spring 1 5 to drive the coulter 6 into the ground, even if the ground has not been ploughed.

The provision of the springs ensures that, if the coulter hits a stone, or other large object in the ground, the coulter can, if necessary, rise against the downwardly directed force transmitted to the coulter bar by the springs. Equally if there is a sudden dip or hollow in the ground the coulter will be driven downwardly by the spring 15, and if necessary also via the spring 14, so that the coulter continues to cut a slit in the ground even under such circumstances.

When a drill in accordance with the invention is utilised it is envisaged that the drill may be utilised to plant grain crops on ground that has not been recently cultivated, although a drill in accordance with the invention may also be based to plant other types of crops. Indeed it is envisaged that when utilising a drill in accordance with the present invention it will be possible to drill a field directly after a combined harvester has completed reaping a previous crop. It is envisaged that in utilising the drill seeds will be introduced through the pipe 8 and fertilizer will be introduced through the pipe 9 into the slit cut in the ground by the coulter 6.However it is possible that seeds of different types may be introduced through the pipes 8 and 9, and it is also possible, of course, for fertilizer to be introduced through the pipe 8 and seeds to be introduced through the pipe 9.

When a drill as described above is being utilised, as the coulter 6 cuts a slit in the ground, the soil will tend to swirl into the space left behind the coulter as the coulter is drawn along, thus effectively filling the slit cut in the ground with a fine tilth. The pipe or pipes through the seed of seeds are introduced to the slit are so located that the seeds are deposited in the swirl of tilth located behind the coulter 6. Thus the seeds come to rest with tilth below them and with tilth above them.

This is, of course, an ideal situation for germinating seeds, since the seeds are entirely surrounded by soil and can thus germinate readily.

The routes and chutes generated by the seed will readily be able to penetrate the fine tilth, and thus successful germination of the seed will not be hindered in any way. Thus the seed will be planted in optimum conditions, even though the field in which the seeds are planted has not been ploughed since a previous crop has been reaped.

Whilst the invention has been specifically described with reference to one embodiment in which springs are utilised as resilient means to urge the coulter downwardly into the ground it is to be appreciated that other resilient means could be utilised. For example one or both of the springs could be replaced by a series of resilient nonplanar washers, such as the washers that are sometimes known as bellville washers. The washers wouid be arranged in a stack, the alternate washers being alternately oriented. One advantage of utilising such a series of washers is that a linear spring tension could be produced.

Alternatively one or both of the springs could be replaced by appropriate gas struts, or even with one or more resilient members such as a rubber cone corresponding to a rubber cone sometimes utilised in connection with the rear suspension of a motor vehicle. Thus it is to be appreciated that whilst reference has primarily been made to springs in the foregoing description, the invention is not restricted to the provision of such springs.

It is to be understood that a drill in accordance with the invention will include a plurality of coulter bars as described, which are located parallel to one another extending across the width of the drill, and a single rotatable shaft 21 will be connected, by respective elongate members 10, to the individual coulter bars.

Claims

1. A drill comprising a pivotally mounted coulter bar carrying a coulter in the form of a narrow blade to cut a slit in the ground, and means for moving the coulter bar from a lowered operational position to an elevated nonoperational position, said means including an elongate member connected to the coulter bar, a member which is axially slidable on the elongate member, and means for driving said slidable member, there being two resilient means mounted adjacent the elongate member which engage an abutment adjacent the coulter bar and which can engage said slidable member, the first resilient means being a relatively long means of low strength and the other resilient means being a relatively short means of higher strength.

2. A drill according to claim 1 wherein the coulter is a narrow blade having a tungsten carbide cutting edge.

3. A drill according to claim 1 or claim 2 wherein the coulter is releasably attached to the coulter bar.

4. A drill according to any one of the preceding claims wherein the first resilient means biases the slidable member against an adjustable stop provided at the end of the elongate member remote from the coulter bar when the coulter bar is in the elevated non-operational position.

5. A drill according to claim 4 wherein the adjustable stop comprises a screw threaded member provided on a screw threaded terminal portion of the elongate member.

6. A drill according to any one of the preceding claims wherein the slidable member is driven by a lever protruding from a rotatable shaft, there being means to rotate the shaft to cause a resultant movement of the coulter bar.

7. A drill according to any one of the preceding claims including at least one pipe mounted on the coulter bar, the arrangement being such that, in operation of the drill, seeds can be passed through the pipe into the slit cut in the ground by the coulter.

8. A drill according to claim 7 including a second pipe mounted on the coulter bar, the arrangement being such that, in operation of the drill, seed or fertilizer can be passed through the second pipe into the slit cut in the ground by the coulter.

9. A drill according to any one of the preceding claims comprising a plurality of said coulter bars and coulters.

10. A drill according to any one of the preceding claims wherein one or both of said resilient means comprise springs.

11. A drill according to any one of the preceding claims wherein one or both of said resilient means comprise resilient non-planar washers.

12. A drill according to any one of the preceding claims wherein at least one of the resilient means comprises a gas strut.

13. A drill comprising a narrow blade to cut a slit in the ground andtp form a swirl of tilth behind the blade in the slit and including means to introduce seeds into said tilth so that the seeds come to rest with tilth below them and tilth above them.

14. A drill according to any one of claims 1 to 1 2 wherein said blade is adapted to cut a slit in the ground and to form a swirl of tilth behind the blade in the slit and including means to introduce seeds into said tilth so that the seeds come to rest with tilth below them and tilth above them.

1 5. A method of drilling comprising the steps of cutting a slit in the ground with a blade to form a swirl of tilth behind the blade, and introducing seeds into said tilth so that the seeds come to rest with tilth below them and tilth above them.

1 6. A drill substantially as herein described with reference to and as shown in the accompanying drawings.

17. A method of drilling as herein described with reference to the accompanying drawings.

1 8. Any novel feature or combination of features disclosed herein.