WO2000056136A1

WO2000056136A1 - Apparatus for weeding between planted row crops

Info

Publication number: WO2000056136A1
Application number: PCT/NL2000/000176
Authority: WO
Inventors: Gerrit Jan Dijk
Original assignee: Gerrit Jan Dijk
Priority date: 1999-03-22
Filing date: 2000-03-17
Publication date: 2000-09-28
Also published as: CA2333246A1; NL1012997C2

Abstract

Automatic weeder for weeding between planted row crops (12a, 12b, 12c, 12d). The automatic weeder comprises blades (5a, 5b, 5c, 5d, 8a, 8b, 8c, 8d), mounted onto movable connecting rods (4, 7) and guiding means (16a, 16b, 16c, 16d), mounted onto the blades, which guiding means (16a, 16b, 16c, 16d) operationally lean against the rows to be weeded. In a state of rest the blades (5a, 5b, 5c, 5d, 8a, 8b, 8c, 8d) are moved away from the row crops and in an active state the blades (5a, 5b, 5c, 5d, 8a, 8b, 8c, 8d) are moved towards the row crops, the guiding means (16a, 16b, 16c, 16d) thereby preventing the blades (5a, 5b, 5c, 5d, 8a, 8b, 8c, 8d) from damaging the crop.

Description

Apparatus for weeding between planted row crops

The invention relates to an arrangement for weeding between planted or seeded row crops, comprising a frame to which weed cutting blades are mounted, which blades can be pulled under ground level along a number of plant rows .

Arrangements of this kind are known. Usually a number of blades, connected to a frame, are simultaneously pulled between plant rows with the aid of a tractor. The problem is that the mutual distance between the plant rows or groups of plant rows may vary and that the navigational skills of the driver of the tractor are limited, which makes it necessary to adjust the weed cutting blades such that they always maintain a certain distance to the plant rows in order to prevent a loss of plants. The concomitant disadvantage is that relatively wide strips of soil are left unweeded adjacent to the plant rows, on which strips weeds may flourish. Especially with a slowly growing crop the weed may overgrow the crop and dry out the soil. This limits tne effectiveness of weeding as a method for eradicating weeds and it makes eradicating weeds by using herbicides more attractive, which is less desirable from an environmental point of view.

The inventive arrangement obviates this drawback and is characterized m that the arrangement comprises at least four blades, that a first half of the number of blades is mounted onto a first connecting rod, that a second half of the number of blades is mounted onto a second connecting rod, that each of both connecting rods is mounted with at least two parallel running arms to tne frame, and that each connecting rod is connected to guiding means, operationally guided alongside of the row crops. The inventive arrangement is especially well suited for weeding between rows of a crop standing on a relatively strong stem, like maize or young trees, because the crop must be capable of offering at least some resistance to the guiding means. The guiding means thus move along the rows and prevent the blaoes from damaging the crop in the rows.

An arrangement for weeding provided with guiding means is knov-n from US-A- 2,633,790, but with this arrangement the guiding means are exclusively used for lifting up the crop, such that the weed cutting blade moving alongside of the guiding means will not damage the crop.

A favourable embodiment of the invention is characterized in that operationally the first half of the number of blades is mounted such that a first side of a number of rows is weeded and that the second half of the number of blades is mounted such that the second side of a number of rows is weeded. For a crop, standing on a relatively strong stem it is sufficient to connect one guiding means to each connecting rod, under the assumption tnat the distance between the successive rows is the same. This is for example the case wnen for example four rows have been planted or seeded simultaneously by a machine. It is advantageous then to construct an arrangement with exactly four pairs of blades and to weed the rows m a pattern that corresponds to tne pattern followed by tne planting machine or seeding machine. For a crop standing on a less strong stem or for a yoang crop, it is advantageous to equip each blade with guiding means, as a result of wnich the forces exerted to tne stems will be more evenly distributed via the mutual connecting rod.

A favourable embodiment of the arrangement, which enables adjustments to be made to the weeding process, for example for the type of crop, is characterized in that steering means are provided, for steering the connecting rods at least substantially perpendicular to a direction of the rows. An additional advantage is that the blades can be moved apart before one starts weeding a new row and that the blades can be steered towards the rows while driving, with the guiding means preventing the crop from being damaged by the blades. A favourable embodiment in which the position of the blades is determined even when there is no explicit steering, is characterized in that the steering means comprise means for moving the blades away from the crop rows in a state of rest. These means may for example comprise spring means, but it is also possible to construct a suspension of the connecting rods such that when the arrangement is lifted-up, which always happens on a begin or an end of a row, the blades will move away from the crop because of their own weight.

Another favourable embodiment is characterized in that the steering means comprise at least means for operationally moving the olaoes towards tne crop rov.s, by moving the connecting roαs with respect to each other. De steering means may be operated via a control lever by the driver, but it is also possible to operate the steering means by lowering tne arrangement or by exerting a pulling force onto the arrangement.

Another favourable embodiment of the arrangement is characterized in that the at least one guiding means is hinged. According to the invention the guiding means move along the rows and over an uneven ground level, thereby guiding the oiades an tne vertical direction as well. In this emDooimeπt, the guiding means preferably comprise an at least substantially rod-shaped or sKi-shaped ob ect. A favourable embodiment according to another aspect of the invention, with which wide strips can oe weeded even if the ground is very uneven, is characterized in that the blades are each individually, via a blade stem and a blade holder, hinged to two arms mounted in parallel, and that the arms are hinged to a connecting rod. In this manner, a blade can move in a vertical direction while the attitude of the blade remains unchanged. A very favourable embodiment is characterized m that each blade is provided with guiding means, mounted to its blade stem or blade holder, for operationally at least substantially leaning against the row crops, such that each blade is steered in a vertical direction and that the strain exerted to the stems of the row crop is minimized.

A favourable embodiment according to another aspect of the invention, which uses the exact steering obtained with the guiding means mounted in th-, s manner, is characterized m that a finger weeder is mounted to an end of eacn guiding means, such that the soil between individual plants m a row can be treated as well.

The invention will now be further explained witn reference to the following figures, m which:

Fig. 1 schematically represents in too view a possible emoodiment of tne arrangemert -in a state of rest; Fig. 2 schematically represents m top view the same emoodiment m ai operational position; Fig. 3 schematically repiesents m side view a possible suspension of a biaαe and guiding means; Fig. 4 schematically represents in side view an alternative suspension of a olaoe and guiding means ; Fig. 5 schematically represents in side view a blade, guiding means and a finger weeder.

Fig. 1 schematically represents in top view a possible embodiment of the arrangement in a state of rest, comprising a frame 1, provided with wheels 2a, 2b, 2c, to which two arms 3a, 3b are mounted, to which arms a first connecting rod 4 is mounted, to which four blades 5a, 5b, 5c, 5d are mounted via blade holders and blade stems. Also to frame 1 two arms 6a, 6b are mounted, to which arms a second connecting rod 7 is mounted, to which four blades 8a, 8b, 8c, 8d are mounted via blade holders and blade stems. Frame 1 is coupled to a lifting gear 9, which is part of a tractor 10. Operationally the wheels 11a, lib of tractor 10 are positioned precisely between the crop rows 12a, 12b, 12c, 12d of for example young maize plants. Before the four rows are weeded, tractor 10 is brought into position, with the arrangement lifted up with the aid of lifting gear 9. During this operation the blades are centrally positioned between the rows, for example because two springs 13a, 13b pull the connecting rods 4,7 to this neutral position or because the suspension of the arms is made such that gravitational forces move them to this position. Once tractor 10 is positioned, then the blades are lowered with the aid of lifting gear 9. At the same time, the blades are moved towards the rows 12a, 12b, 12c, 12d by mutually displacing the connecting rods 4,7. In the figure this is schematically shown by a 3owden cable 14 to which a tensile force can be applied, which causes connecting rod 4 to move to the left and connecting rod 7 to move tc the right. Bowden cable 14 can be operated manually by a driver of tractor 10, but it may also be coupled to lifting gear 9, such that a tensile force is applied tc it when the blades are lowered. In order to prevent the plants in the rows 12a, 12b, 12c, 12d from being damaged, a stop 15 is provided, for limiting the movement of connecting rod 7. Stop 15 is mounted such that a distance of for example 10 cm. is maintained oetween the blades . In order to centre the crop rows between the blades, rod-shaped or ski-shaped guiding means 16a, 16b, 16c, 16d are provided, mounted to the blade stems or to the rods 4,7, which slide over the ground and alongside of the rows 12b, 12c. Preferably, a front side of the guiding means is directed slightly upwards ana slightly away from the adjacent row, such that the guiding means is not caught in the crop or in the soil .

The embodiment shown here is provided with only four guiding means, which is sufficient if the crop stands on a sufficiently strong stem. For more fragile plants, it may be advantageous guide the guiding means on both sides of the rows 12a, 12D, 12c, 12d; such the forces exerted to the rows are equally shared by all four rows.

Fig. 2 schematically represents in top view the same embodiment in an operational position, daring wnicr the blaoeε 5a, 5b, 5c, 5d move closely along tne right sides of the rows 12a, 12o, 12c, 12d and tne Dlades 8a, 3d, 8c, 8d move closely along the left side. The distance oetween the blades is at least substantially determined by the location of stop 15, whicn rests now against connecting rod ^"J The location of the blades around the rows is steered by the guiding means 16a, 16b, 16c, 16d, which slide now closely alongside of the crop rows. Incidentally tney h_t one or a few plants and in doing so they adjust ootn connecting rods 4,7 and steer all blades. It is important than that distances between the rows are equal, actually, this is always the case when the rows are seeded or planted automatically in one operation. Fig. 3 schematically represents in side view a possible suspension of a blade 8 and guiding means 16. According to the invention, it is advantageous to enable every blade to move in a vertical direction, such that with an uneven ground level a constant weeding depth can be obtained. For that purpose, blade 8 is connected via a blade stem 18 to a blade holder 19, which is in turn hinged to two parallel running arms 20a, 20b, which are hinged to a connecting piece 21, which is mounted to for example arm 4. It is assumed that arms 4,7 at least substantially do not move in a vertical direction and that their height is at least substantially determined by lifting gear 9 or possibly by supporting wheels 2a, 2b, 2c, mounted underneath frame 1. An unevenness in the soil will then be noticed by guiding means 16, which will lift up blade holder 19 via a hinge 22 and a rod 23, which causes blade 8 to rise too. Because of the application of two parallel running arms 20a, 20b, the orientation of blade 8 will remain the same while moving. Guiding means 16 is provided with a curl 24 on its front side, in order to prevent the front side tc be stuck in the ground. Curl 24 moreover bends away from row 12, in order to prevent the front side to be caught Pehind a plant.

Fig. 4 schematically represents in sioe view an alternative suspension of a blade 8 and guiding means 16, which also comprises a wheel 25, mounted tc rod 23, on a side turned away from the adjacent crop row 12 anc next to guiding means 16. Wheel 25 does good service if the kind of soil is such that guiding means 16 is ir.clinec to disappear in the ground. At that instance wheel 25 touches the ground and prevents guiding means 16 from sinking away any further. The engagement of wheel 25 may ce further improved by introducing a spring-loaded element or a hinge between the suspension of wheel 25 and the r.mge 22. Fig. 5 schematically represents in side view a blade 8, guiding means 16 and a finger weeder 26. Finger weeder 26 comprises a rotatable mounted metal disc 27, to which a number of projections 28 are mounted, made of rubber. Metal disc 27 is mounted such that it cannot touch plant row 12, but the rubber projections 28 can. Moreover, they touch the ground between the plants 12 and effectively remove weeds. Finger weeders known in the art are m general moved with a rather low speed alongside of a crop. For that reason, they are made such that a peripheral velocity of the projections is higher than the velocity of the finger weeder. The finger weeder shown here is moved with a high speed alongside of the crop, together with the weeding arrangement. It is advantageous then to select the peripheral velocity of the projections 28 to be lower than the velocity of the finger weeder. This can easily be obtained by introducing a certain amount of friction into the bearing of metal disc 27.

Claims

1. Arrangement for weeding between planted or seeded row crops, comprising a frame to which weed cutting blades are mounted, which blades can be pulled under ground level along a number of plant rows, characterized in that the arrangement comprises at least four blades, that a first half of the number of blades is mounted onto a first connecting rod, that a second half of tne number of blades is mounted onto a second connecting rod, that each of both arms is mounted with at least two parallel running arms to the frame, and that each connecting rod is connected to guiding means, operationally guided alongside of the row crops .

2. Arrangement according to claim 1, cnaracterized in that operationally the first half of the nu oer of blades is mounted such that a first side of a number of rows is weeded and that the second half of the nimber of blades is mounted such that the second side of a number of rows is weeoed .

3. Arrangement according to claim 2, cnaracterized in that steering means are provided, for steerng the connecting rods at least substantially perpendicular to a direction of the rows.

4. Arrangement according to claim 3, cna: actenzeα in that the steering means comprise means --.or moving tne blades away from the crop rows m a state of rest.

5. Arrangement according to claim 3, ciaracterizeα in that the steering means comprise at least means for operationally moving the blades towards the crop rows.

6. Arrangement according to claim 1, characterized in that the at least one guiding means is hinged.

7. Arrangement according to claim 6, characterized in that a guiding means comprise an at least substantially rod-shaped or ski-shaped object.

8. Arrangement according to claim 1, characterized in that the blades are each individually, via a blade stem and a blade holder, hinged to two arms mounted in parallel, and that the arms are hinged to a connecting red.

9. Arrangement according to claim 8, characterized in that each blade is provided with guiding means, mounted to its blade stem or blade holder, for operationally at least substantially leaning against the row crops.

10. Arrangement according to claim 9, characterized in that a finger weeder is mounted to an end cf each guiding means .