GB2480237A

GB2480237A - Seed drill

Info

Publication number: GB2480237A
Application number: GB1007698A
Authority: GB
Inventors: Samuel Moore
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-05-10
Filing date: 2010-05-10
Publication date: 2011-11-16
Also published as: GB201007698D0

Abstract

A seed drill comprises a frame12, at least one drag arm20pivotally mounted on the frame to extend rearwardly from the frame, a slit cutting disc24,26being mounted on each side of the drag arm for opening respective slits for receiving seeds, each disc having an acute angle of incidence relative to the direction of travel of the seed drill, wherein the discs are arranged substantially symmetrically on either side of the drag arm about the longitudinal axis of the drag arm. The angle of incidence may be around 3-4 or approximately 1.5°. The drag arm may be mounted on the frame via resilient suspension means22. The seed drill may have slit closing means30,32provided behind the discs which may have a serrated or profiled edge.

Description

Seed Drill This invention relates to the agricultural sowing of seeds by the technique of slit sowing in which seeds are implanted in slits or narrow slits cut in the ground, not necessarily cultivated or otherwise prepared except, in suitable cases, where vegetation is killed by the application of suitable chemicals. Such is often referred to as "no-till" seeding.

According to the present invention there is provided a seed drill comprising a frame, at least one drag arm pivotally mounted on the frame to extend rearwardly from the frame, a slit cutting disc being mounted on each side of the drag arm for opening respective slits for receiving seeds, each disc having an acute angle of incidence relative to the direction of travel of the seed drill, wherein the discs are arranged substantially symmetrically on either side of the drag arm about the longitudinal axis of the drag arm. Each disc may be inclined at an angle of incidence to the direction of travel of the seed drill at an angle of around 3 to 4°. Preferably each disc is inclined to the vertical, preferably by an angle of approximately 1.50.

The symmetrical arrangement of the discs on the or each drag arm cancels out any lateral forces applied to the drag arm by virtue of the angle of the discs.

Preferably said at least one drag arm is mounted on the frame via a resilient suspension arrangement.

Preferably the seed drill comprises a plurality of drag arms arranged in one or more transversely extending rows on the frame, each drag arm having a pair of rotatable discs symmetrically mounted on either side thereof.

Preferably said plurality of drag arms are arranged in a plurality of rows, the drag arms being arranged in staggered formation such that a slit cut by a respective slit cutting disc of a drag arm of one row is arranged between the slits cut by adjacent slit cutting discs of the drag arms of an adjacent row to reduce the spacing between rows.

A slit closing means may be provided behind the slit cutting discs of the at least one drag arm.

Said slit closing means may comprise a press roller or array of press wheels or discs, preferably having a serrated or profiled edge, mounted on a transverse shaft behind the drag arms. Such slit closing means may be mounted on trailing arms extending from the frame. Said trailing arms may be pivotally connected to the frame so that the height of the slit closing means may be adjusted with respect to the frame.

A coulter may be associated with each slit cutting disc for delivering seeds into the slit formed thereby. Alternatively a seed distributing means may be provided for broadcasting seeds into the slits formed by the slit cutting discs.

In one embodiment a slit closing means, preferably in the form of a press wheel, is mounted on the or each drag arm behind the respective slit cutting discs thereof for closing a slit formed by said respective slit closing disc. Said slit closing means may be mounted on a trailing arm extending from the or each drag arm. Said trailing arm may be pivotally mounted on said drag arm and may be provided with height adjustment means, whereby the height of the slit closing means may be adjusted with respect to said drag arm to adjust the cutting depth of the slit cutting discs thereof.

Said slit closing means may comprise a separate press wheel mounted on each side of said trailing arm. Said press wheels may be arranged at an acute angle to the direction of movement of the seed drill. Preferably said press wheels are arranged substantially symmetrically on either side of the trailing arm to balance any lateral force applied to the respective drag arm by each wheel due to the angle thereof. Each press wheel may have a serrated or profiled edge.

The frame of the seed drill may be adapted to be mounted on a three point linkage of a tractor.

An embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:-Figure 1 is a perspective view of a seed drill according to an embodiment of the present invention; Figure 2 is a plan view of the seed drill of Figure 1; Figure 3 is a detailed side view of a drag arm of the seed drill of Figure 1; Figure 4 is a plan view of the drag arm of Figure 3; and Figure 5 is a perspective view of the drag arm of Figure 3.

As shown in the drawings, as seed drill 10 according to an embodiment of the present invention comprises a frame 12 having mounting points 14,15,16 at a forward end thereof for mounting on a three point linkage of a tractor. Two rows A,B of independently mounted drag arms 20 are pivotally mounted on the frame by means of a resilient mounting 22 to extend rearwardly and downwardly from the frame 12.

A pair of slit cutting discs 24,26 are mounted on each drag arm 20, one disc 24,26 being provided on each side of the drag arm. Each disc 24,26 is mounted at an acute angle to the direction of movement of the seed drill and is inclined to the vertical such that each disc 24,26 cuts and opens a slit as the seed drill moves across the ground.

The slit cutting discs 24,26 on each drag arm 20 are arranged symmetrically on either side of the longitudinal axis of the drag arm 20 whereby the lateral forces applied to the drag arm 20 due to the angle of the discs 24,26 oppose and balance each other out to leave no resultant lateral force on the resilient mounting 22 of the drag arm 20.

A coulter 40, comprising a seed delivery tube, is associated with each slit cutting disc 24,26 for delivering seeds into a slit cut by the respective disc 24,26. Alternatively seeds may be broadcast into the slits cut by the discs 24,26 from a seed distribution apparatus.

A trailing arm 28 is pivotally mounted on a rear end of each drag arm 20. A pair of slit closing press rollers 30,32 are mounted on a rear end of the trailing arm 28. Each press roller 30,32 is arranged to close the slit formed by a respective slit cutting disc 24,26 mounted ahead of the respective press roller 30,32 on the drag arm 20. Each press roller 30,32 has an angled and serrated edge to improve the effectiveness of the press roller. Such closing rollers are of the type sold by Guttler, often referred to as a "Guttler wheel" or "Guttler ring".

The rear end of the trailing arm 28 is connected to the drag arm 20 via a height control mechanism 34 such that the height of the press rollers 30,32 with respect to the drag arm 20 to which they are connected can be adjusted to adjust the cutting depth of the slit cutting discs 24,26.

The press rollers 30,32 are angled at an acute angle of incidence relative to the direction of travel of the seed drill opposite to that of the corresponding leading slit cutting disc 24,26. As with the slit cutting discs 24,26, the press rollers 30,32 are arranged symmetrically on either side of the drag arm to balance out the lateral forces applied to the drag arm 20 by the press rollers 30,32.

A row of serrated press rollers 50 are mounted on a transverse axle mounted at a rear end of the frame 12 on trailing support arms 52,54. The support arms 52,64 are adjustably mounted on the frame 12 to enable the height of the press rollers 50 to be adjusted with respect to the frame 12. The press rollers 50 are arranged into two groups on either side of the frame, each group comprising an equal number of rollers, the orientation of the rollers of one group being opposite to that of the other group such that any lateral force applied to the frame by the angled and serrated edges of the rollers is cancelled out to leave no resultant force on the frame.

As can be seen from Figure 2, the slit cutting discs 24,26 of the rearmost row B of drag arms 20 are staggered with respect to the slit cutting discs 24,26 of the forward row A so that slits cut by the slit cutting discs 24,26 of the rearmost row B are interposed between the slits cut by the slit cutting discs 24,26 of the forward row A of drag arms 20. Whilst the embodiment shown in the drawings comprises two rows of drag arms 20, it is envisaged that three or more staggered rows of drag arms may be provided to provide narrower row spacing.

The invention is not limited to the embodiment(s) described herein but can be amended or modified without departing from the scope of the present invention.