GB2072474A - Seed drill coulters - Google Patents

Abstract

A seed drill has at least one coulter support, to which, via coulter struts (4) sowing coulters (5) are arranged in at least two cross rows located one behind the other and in staggered arrangement and pivotal in a vertical plane. Springs (9) are arranged between a rail or bar (13) extending above the coulter struts (4) at right angles to the direction of travel (32) and holders (6) located on the coulter struts. A stop (24) restricts the downward movement of the struts when the drill is raised into a transport position. A latch (20) provides an upper stop for the coulters in operation and a lower stop (22) when the sowing coulters (5) are lifted. <IMAGE>

Description

SPECIFICATION Seed drill The present invention relates to a seed drill having at least one coulter retaining support on which, by means of coulter struts in at least two cross rows located one behind the other, sowing coulters are pivotally mounted in staggered formation, whereby springs are mounted above the coulter struts between a rail extending at right angles to the direction of travel and holders arranged on the coulter struts.

German Patent Specification 1,279,408 already discloses a similar seed drill wherein the springs are located above the coulter struts whereby a low-lever connection of the coulter struts to the coulter retaining support is possible. An adverse feature in this seed drill is that due to the holders to which the springs are secured projecting forwardly far beyond the joints, an inexpediently elongate method of construction of the apparatus is required.

This is of particular disadvantage in attachment implements, when used in combination with soil cultivating implements, because for lifting out the machine with the centre of gravity shifted far to the rear requires considerable lifting forces of the hydraulics of the tractor. Moreover, in this type of use of the seed drill access is difficult to the adjusting devices to vary the tension of the springs, mounted at the front.

Furthermore, a central spring pressure adjustment is disclosed by the DE-OS 2,310,805, which adjustment is located at the front of the seed drill. This arrangement has proved to be a problem both with direct attachment of the seed drill to the tractor and using the seed drill in combination with soil cultivating implements. In modern agricultural tractors there is no possibility of the driver operating the central spring pressure adjustment from the tractor, due to conditions created by the design of the tractor since the region behind the tractor can no longer be reached.

An object of the invention is to obtain an expedient mode of construction of a seed drill having a simple, readily accessible and accurately adjustable coulters for all operational conditions prevailing in practice.

According to the present invention there is provided a seed drill having at least one coulter holder support on which via coulter struts, seed coulters are mounted in at least two cross rows located one behind the other in staggered formation and pivotable in upright or upwardly extending planes, whereby springs are mounted above the coulter struts between a rail or bar extending at right angles to the direction of travel and holders located on the coulter struts, characterised by the feature that the springs are located horizontally and behind the pivotal axes of the coulter struts with respect to the normal direction of travel and that the connecting points of the springs are situated on the holders in the region above the pivotal axes of the coulter struts, and that the bar extending at right angles is mounted behind the pivotal axes of the coulter struts.

To obtain a short, compact overall construction of the seed drill and hence connected therewith a shifting of the centre of gravity forwardly, provision is made according to the invention for the holders to be located behind the pivotal axes of the coulter struts and to have a portion extending forwardly upwards.

Moreover; it is provided in accordance with the invention for the stops for limiting the pivotal range of the coulter struts downwardly from an upper out-of-operation position of the individual coulters. This makes is possible to avoid unnecessary wear at the sowing coulters not required for sowing the seeds, since the sowing coulters may simply be pivoted upwards.

If the stops are formed as catches pivotally connectable to the support and engageable in the holders, then a simple upward pivoting of the sowing coulter is obtained. A particularly favourable embodiment of the invention having automatic engagement of the catches in the out-of-operation position of the sowing coulter is obtained in that the catches abut against the holders up to the stop position.

In order in the raised transportation position of the seed drill for the sowing coulters to be retained lifted-off the ground, further stop for defining the pivotal range of the coulter struts downwardly are provided in accordance with the invention.

In a preferred embodiment, these further stops are comprised of further stop or check members connected to the support and located on the holders and stop elements abutable against the check members. A compact method of construction of the coulter struts is obtained by way of this means.

The invention further provides for the bar or rail to be located behind the sowing coulters.

By this means, the bar may on the one hand act as a foot plate, in order with a somewhat higher method of construction of the seed drill to permit easier filling of the storage container.

To enable the coulter pressure to be adapted to various kinds of soil and firmnesses, the springs according to the invention are located on the rail with variable tensional adjustment. This, for example, makes it possible to increase the coulter pressure for the sowing coulter travelling along the tractor track. Moreover, it is proposed in order to obtain a simple adjustment of the tension of all springs, for the rail to be adjustable in the operational direction of the springs. This is obtained in simple manner in that the rail is adjustable by at least one spindle. For using the seed drill in combination with soil cultivating implements the rail should preferably be hydraulically adjustable.

The arrangement in accordance with the invention of the springs and the compact overall structure of the seed drill is not only limited to fitting the seed drill with standard sowing coulters, but is also provided for the sowing coulter to be formed as a single disc coulter. The short overall structure of the seed drill is made possible in that the single disc coulters are connected by means of coulter struts of the same length to two coulter holding supports located one behing the other and extending at right angles to the direction of travel, whereby the spacing between the front side of the rear coulter holding supports and the joints of the front coulter struts is greater than the length of the complete coulter struts with sowing coulters.

To permit close sowing with the single disc coulters and simultaneous short overall structure of the seed drill with only two cross rows, the invention provides for the single disc coulters within each cross row to be set diagonally or inclinedly to the direction of travel, whereby the setting of the single disc coulters in the front row is opposed or opposite to that in the rear row. To permit the machine to be made lightweight in structure and hence permitting the later forces to be mutually cancelled, it is further provided that the front cross row has one more sowing coulter than in the rear cross row.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a section in side view of a seed drill; Figure 2 is an enlarged elevational view of a set with two stops for arrangement of a sowing coulter; and Figure 3 is a fragmentary plan view of a seed drill in accordance with the invention.

A seed drill is shown in a section in Fig. 1, which in known manner (not shown) is constructed as a trailer or attachment machine and also has an arrangement of a double row of coulters connected to a coulter holding support 1. In this instance struts 2 for the rear cross row are welded to the coulter holding support 1. Also located on the coulter holding support 1 and on the rear end of the struts 2 are the joints 3 for coulter struts 4 to which sowing coulters 5 are secured. Thus, the joints 3 are welded-on below the struts 2, so that the force components directed upwardly and produced by the engagement of the sowing coulters 5 in the ground are kept as small as possible. Furthermore, holders 6 are welded to the coulter struts 4. Bolts 7 project laterally at the upper ends of the holders 6 and the bolts are formed at one end as connecting points 8 for springs 9.These springs 9 are located horizontally and above the coulter struts 4. In order to permit use of springs 9 of equal length for the sowing coulters 5 located in two cross rows, suitable extension rods 10 or 11 are located between the springs 9 and the connecting points 8.

Above the sowing coulter 5 of the rear cross row and behind the pivotal axes 1 19 of the joints 3, a bar or rail 1 3 is pivotally mounted on two longitudinal struts 14, which struts project towards the rear and are welded to frame 1 5. The springs 9 are latched-in on a downwardly projecting portion 16 of the rail 1 3 so as to be individually adjustable in tension by means of an apertured rail 1 7. The rail 1 3 may be pivoted by means of a threaded spindle 18 and hence the tension of the springs 9 adjusted centrally and infinitely variably. The arrangement of the rail 1 3 behind the seed drill renders the apertured rails 1 7 and spindle 18 readily accessible.Thus, for example, with this seed drill in which checking the penetration depth T of the sowing coulters and hence the seed depositing depth is possible only from the rear, the operator may adapt the tension of the springs from this rear position in accordance with prevailing conditions.

Fig. 2 shows check members 1 9 welded to the struts 2. Catches 20 are pivotally mounted on check members 1 9 and the catches 20 are provided for the upper check position of the sowing coulters 5. In the operational position of the sowing coulters these catches 20 abut from above against the bolts 7 rigidly connected to the holders 6.

When the sowing coulters 5 are lifted, the bolts 7 slide along the catches 20 until the catches 20, shortly before reaching the out-ofoperation or inoperative position of the sowing coulters tilt forwardly and downwardly into the check position 21 shown by chain-dotted lines, in which they form the stops 22 for the coulter struts 4 and hence for the sowing coulters 5.

When the seed drill with the sowing coulters is raised into the transportation position the rear, raised portion 23 of the check members 1 9 presents in combination with the bolt 7 a further stop 24 for defining the downward pivotal range of the coulter struts 4.

Fig. 3 is a sectional view of a seed drill in accordance with the invention which is fitted with two coulter holder supports 25 and 26 located one behind the other and on which single disc coulters 27 are located by means of coulter struts 28 of equal length and by means of pivots or joints 29 and 30. Spacing A between front side 31 of the rear coulter holding support 26 and the joints 29 of the front coulter struts 28 is greater than length L of the complete coulter struts 28 with sowing coulters 27.

The single disc coulters 27 are set diagonally or inclinedly to the normal forward direc tion of travel indicated by arrow 32 and within each cross row are set in the same direction. This setting, however, is opposed in the single disc coulters 26 of the front cross row 33 to that of the single disc coulter located in the rear cross row 34.

As shown in the embodiment of Fig. 1, the rail 1 3 herein also is located behind the sowing coulters 27 and the springs 9 and the extension rods 10, 11, above the coulter struts 28.

Claims (1)

1. A seed drill having at least one coulter holder support on which, via coulter struts, seed coulters are mouted in at least two cross rows located one behind the other in staggered formation and pivotable in upright or upwardly extending planes, whereby springs are mounted above the coulter struts between a rail or bar extending at right angles to the direction of travel and holders located on the coulter struts, characterised by the feature that the springs are located horizontally and behind the pivotal axes of the coulter struts with respect to the normal direction of travel, that the connecting points of the springs are situated on the holders in the region above the pivotal axes of the coulter struts, and that the bar extending at right angles is mounted behind the pivotal axis of the coulter struts.

2. A seed drill as claimed in claim 1, in which the holders are arranged behind the pivotal axes of the coulter struts and have a portion extending forwardly and upwards.

3. A seed drill as claimed in claim 1 or 2, in which stops are provided to limit the pivotal range of the coulter struts downwardly from an upper, inoperative position of the individual coulters.

4. A seed drill as claimed in claim 3, in which the stops comprise catches pivotably connected to the support and engageable with the holders.

5. A seed drill as claimed in claim 4, in which the catches abut against the holders shortly before the inoperative position.

6. A seed drill as claimed in claims 1 or 2, in which further stops are provided to limit the pivotable range of the coulter struts downwardly for the raised transportation position of the seed drill.

7. A seed drill as claimed in claim 6, in which the further stops comprise stop or check members connected to the support and stop elements located on the holders and abutting against the check members.

8. A seed drill as claimed in claim 1, in which the bar is arranged behind the seed coulters.

9. A seed drill as claimed in claim 1 or 8, in which the springs are arranged on the bar to be adjustable in tension.

10. A seed drill as claimed in any of claims 1 to 9, in which the bar is adjustable in the operating direction of the springs.

11. A seed drill as claimed in claim 10, in which the bar is adjustable by means of at least one spindle.

12. A seed drill as claimed in claims 10 and 11, in which the bar is hydraulically adjustable.

13. A seed drill as claimed in any of the preceding claims, in which the sowing coulter is formed as a single disc coulter.

14. A seed drill as claimed in claim 13, in which the single disc coulters are connected by means of coulter struts of equal length to two coulter retaining supports located one behind the other and extending at right angles to direction of travel, whereby the spacing (A) between the front surface of the rear coulter retaining support and the joints of the front coulter retaining support is greater than the length (L) of the complete coulter struts with sowing coulters.

1 5. A seed drill as claimed in claims 1 3 or 14, in which, within each cross row each disc coulter is set in the same direction diagonally or inclinedly to the direction of travel, whereby the setting of the single disc coulter in the front row is opposed or opposite to that in the rear row.

16. A seed drill as claimed in claim 15, in which one more sowing coulter is provided in the rear cross row than in the front cross row.

1 7. A seed drill substantially as herein described and illustrated with reference to and as illustrated in the accompanying drawings.

CLAIMS (21 May 1981)

1. A seed drill as claimed in claim 15, in which one more sowing coulter is provided in the front cross row than in the rear cross row.