GB2199223A

GB2199223A - Coulters

Info

Publication number: GB2199223A
Application number: GB08729125A
Authority: GB
Inventors: Svend Thejsen
Original assignee: THRIGE AGRO AS
Current assignee: THRIGE AGRO AS
Priority date: 1986-12-15
Filing date: 1987-12-14
Publication date: 1988-07-06
Anticipated expiration: 2007-12-14
Also published as: GB2199223B; DK602186A; DK602186D0; SE8704784D0; FR2608005B3; FR2608005A1; DE3740746A1; SE8704784L; GB8729125D0

Description

n " 219922-J 1 - COULTERS This invention relates to coulte-rs,

particularly but not exclusively for use on a seed drill, comprising an arm which can oscillate about an axis, and is designed to tip when it encounters large obstacles.

Such a coulter is known from Canadian Patent No. 196230.

Coulters are subjected to very strong forces when they encounter obstacles in the ground such as stones. Also they are subjected to wear and it is therefore usual to reinforce the seed conduit against wear by providing a coulter made of a hard material which may, for example, be welded on the conduit.

Published European patent application No. 0 154 260 discloses an additional coulter body which forms a prologation extending downwardly from the normal coulter il, 2 and which is easy to mount if the seed has to be deposited deeper than normal such as in the case of bean seed. The lowest point of the coulter body is considerably deeper than the lower edge of the normal coulter and the width of the coulter body in the direction of travel of the coulter is the same as the width of the front part of the normal coulter.

Despite the foregoing no hitherto known coulter has been satisfactory especially in use in soil containing a large number of obstacles such as stones.

Consequently it is an object of the present invention to provide a coulter which can be utilised in soil without difficulties or problems arising such as those aforesaid, and particularly in soil containing many obstacles such as stones.

With this object in view the present invention provides a coulter for use on a seed drill comprising an arm which can oscillate about an axis, and is designed to tip when it encounters obstacles, characterised in that the coulter also comprises a bracket which is resiliently mounted at one end of the arm.

The coulter of this invention is able to avoid obstacles in the path of its travelling direction as it 4 1, can easily tip across this direction so that the coulter is not difficult to use in earth containing many obstacles such as stones.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which:- Fig. 1 is a side elevation of a first preferred embodiment of the coulter of the invention mounted on a support arm; and Fig. 2 is a part-sectional side elevation of a second preferred embodiment of the coulter of the invention mounted on a support arm.

Referring firstly to Fig. 1, the first preferred embodiment of the coulter 1 is provided with a bracket 2 which is mounted on one end of an arm 10 and is shaped so that it can move or tip laterally when the coulter 1 encounters or engages an obstacle (not s.hown), such as a stone, which it cannot pass by tipping up.

The bracket 2 is mounted resiliently and elastically on the arm 10 by means of a bolt 16 which retains a spring 14 between a -self-locking nut 12 and washer 13 at one end and a washer 15 at the other end of the bolt 16.

On the arm 10 is welded a member 3 for receiving the head of the bolt 16.

On the other end of the arm 10 is a member 11 which is an opening 5 for forming oscillation axis 4 of the arm 10 of the coulter 1.

On the arm 10, between the bracket 2 and the member 11, is a hook 6 for securing or mounting a spring (not shown).

The coulter 1 has on its lower end a piece 7 of hardened steel behind which seed (not shown) is deposited as it comes down from upper part 8 of the coulter 1, which is hollow, and out of the coulter 1 through an opening 9. The piece 7 is secured to the coulter 1 by welding or rivetting.

Referring now to Fig. 2, the second preferred embodiment of the coulter is substantially identical to the embodiment of Fig. 1 and thus like parts have been designated by like reference numerals. However it will be seen from Fig. 2 that the piece 7 on the coulter 1 has been replaced by a body 17, said body 17 being of a plastics material having high mechanical strength and elasticity. if the plastics body 17 is of polyurethane elastomer of suitable hardness its durability can be increased rl C by up to 100%.

Whereas the piece 7 is secured to the coulter 1 of Fig. 1 by means of welding or rivetting, the body 17 can be pressed onto the coulter 1 so that it can be more easily replaced.

Freedom of structure is very important if a better shape is to be obtained resulting in a better flow of earth and plant roots and the like between the coulters so that the embodiment of Fig. 2 is more advantageous than the embodiment of Fig. 1 and it is even cheaper.

The advantages of both embodiments of the coulter of the invention will become apparent from the following description of their use.

In use of the coulter 1, its lower part is pressed against the earth of the spring connected to the hook 6, the arrangement being such that the whole structure with the coulter 1 may oscillate about the axis 4. As long as the moment produced by obstacles is less than the moment from the spring the lowei part of the coulter 1 with the piece 7, or the body 17, will remain at the sa me depth. If a large obstacle is encountered the coulter may either tip over the obstacle and/or move or tip laterally around the obstacle. The body 17 has the further 1 advantage-of being resilient.

By providing the coulter 1 with a bracket 2, or an equivalent member, and by placing the bracket 2 at one end of the arm 10 there is obtained a better effect than would be the case if resiliency was provided by the member 11 on the other end of the arm 10 since in that case the coulter would have an objectional effect on itself or on the seed drill.

The meaning of the term bracket is to be interpreted broadly as covering other forms of support such as a bow shaped member of round iron or a member which is U-shaped in cross-section.

The body 17 may have a hardness of 90 shore and may easily be provided with stops or holding details, and it is easy to remove and replace because despite its hardness it can be cut with a knife. Important also is that its front and sides are smooth and remain free of plant residue.

7 -

Claims

1. A coulter for use on a seed drill comprising an arm which can oscillate about an axis, and is designed to tip when it encounters obstacles, characterised in that the Coulter also comprises a bracket which is resiliently mounted at one end of the arm.

2. A coulter as claimed in claim 1 wherein the bracket is resiliently fa stened in an opening in the arm by means of a spring loaded bolt. -

3. A coulter as claimed in claim 1 or 2 wherein the coulter has a resilient lower part.

4. A coulter as claimed in claim 3 wherein the lower part is a plastics body having high mechanical strength and elasticity.

5. A coulter as claimed in claim 4 wheren the plastics body is of polyurethane elastbmer.

6. -A coulter as claimed in any precedipg claim wherein the bracket is of such a shape that it can be tipped or moved from side to side.

7. A coulter as claimed in claim 6 wherein the brakcet is bow shaped.

8. A coulter as claimed in claim 6 wherein the bra6ket has a U-shaped cross-section.

9. A coulter as claimed in any one of claims 3 to 8 wherein the lower part of the coulter is pressed onto the coulter.

10. A coulter as claimed in any one of claims 3 to 9 wherein the lower part is designed to improve the flow of earth and plant residues between the coulter.

11. A coulter for use on a seed drill by means of an arm which can oscillate about an axis, and is designed to tip when meeting large obstacles, characterised in that the coulter is provided with a bracket which is resiliently mounted at the end of the arm.

12. A coulter mounted on one end of an arm so that it can oscillate about an axis formed by the other end of the arm enabling the coulter to tip when it encounters obstacles in the ground so as to overcome these obstacles, characterised in that the coulter is provided with a bracket by means of which it is resiliently mounted on said one end of the arm.

13. A coulter substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Published 1988 at 'Irlie Patent Office. State House, 8571 High Holborn, London WC1R 4TP. FUrther copies naky be obtained from The Patent O:Mce, Sales Branch. St Mary Cray, Orpington, Kent BR5 3RD Printed by Multiplex - techniques 1W. St Mary Cray, Kent Cor- 1187.