WO2007049963A1

WO2007049963A1 - Assembly and method for plant gripping

Info

Publication number: WO2007049963A1
Application number: PCT/NL2006/050266
Authority: WO
Inventors: Johannes Hendrik Lekkerkerk
Original assignee: Jhl Group
Priority date: 2005-10-26
Filing date: 2006-10-26
Publication date: 2007-05-03
Also published as: NL1030277C2

Abstract

Method and assembly (11) for plant gripping. By means of an device (1) comprising two gripping jaws (4,5) hinged to each other and oblong of design, plants (10) are taken from a tray (15) or the like and put into another tray (14) or the like. The plants (10) are approached and gripped sideways, i.e. essentially perpendicularly to the direction of the main stems of the plants (10). The gripping jaws (4,5) turn on a common pivot (3) and by a pin acting from above they are forced outwards, against the operation of a spring (12) force. This particularly simple construction is insusceptible to contamination and moisture.

Description

Assembly and method for plant gripping

The present invention relates to an assembly comprising a series of devices placed side by side for simultaneously gripping a series of plants, as well as a container for the series of plants, said devices being arranged on a common support displaceable relative to said container and each device comprising two gripping jaws with gripping ends displaceable relative to each other.

Such devices are generally known in the art. The problem is always present that, on the one hand, the plant shall be gripped firmly enough, but, on the other hand, any damage to the plant should be prevented as much as feasible. Especially in connection with young plants, such as plants directly originating from tissue culture, this is an essential problem. In prior art, a plant is gripped from above, i.e. just before the plant gripping action takes place, the gripping jaws make a vertical movement parallel to the main stem of the plant and the jaws are subsequently moved towards each other. Although such gripping devices are satisfactory, they are particularly complex in construction and their further mechanization is complicated and susceptible to failures. An example thereof is found in US 5911631.

The object of the present invention is to propose an improved assembly for plant gripping.

This object is achieved in an assembly described above in that said jaws are elongated jaws with a longitudinal axis and that said support is movable substantially along this longitudinal axis towards said container for gripping said plants, said longitudinal axis being essentially horizontal.

The common support is preferably implemented as a carrier. The movement of the assembly is sideways in relation to the plants, so that an improvement in accessibility is guaranteed. More in particular the assembly described above is used in combination with a special device.

The gripping jaws according to the present invention are particularly arranged to approach and grip the plant sideways, i.e. perpendicularly to the extension of the main stem. Preferably gripping occurs immediately above the root of the plant. In this location the foliage is generally of little volume. According to the present invention the gripping ends of the jaws are moved outwards by a pin-shaped part which is moved between the gripping jaws. According to an advantageous embodiment of the invention the return movement is by means of a spring so that an exactly defined gripping force for the plants can be applied. So, on the one hand any damage can be prevented, whereas on the other hand it is always guaranteed that the plant is engaged firmly enough to effectuate the relevant movement.

Such spring means can be adapted to the relevant plant in a simple way.

Since the gripping jaws according to the present invention are of very simple design, their susceptibility to damage by moisture and contamination is extraordinarily low. In addition, replacement is inexpensive.

According to a further advantageous embodiment of the invention the gripping jaws turn on a common pivot This permits further limitations of costs and an increase in reliability in operation.

The pin by which the gripping jaws are forced away from each other may be pointed at the free end so as to bring about a wider opening between the gripping jaws during further movement. Without this or in addition, however, it is also possible to provide the gripping jaws, near the mounting end, with an outward curvature, creating a funnel- like shape, so that when the pin enters this "funnel" the jaws are gradually opened. In addition, the curvature may be specially designed so that the opening movement does not develop linearly with the pin displacement. So, the opening of gripping ends can be precisely controlled. It stand to reason that the same applies to the closing movement, which may be controlled in such a way that any damage to the plants is avoided.

The pin can be operated in any known manner whatsoever, also by electrical means. However, a pneumatic cylinder-plunger combination is preferably used.

Two of such assemblies may be arranged in opposition to each other, so that a tray may be emptied from two sides and the plants may be transferred to an other tray or, for instance, pot. During this transfer movement, the distance between the plants may be increased. This may be effected e.g. by the construction of the support as a pair of scissors of varying length.

The invention also relates to an assembly with the device described above. Through the invention it is possible to displace not only tissue cultures but also other plants with or without roots. The roots, if present, may be in a substrate, such as a plant plug. The gripping jaws can be made suitable for gripping such plant plugs.

Hereinafter, the invention will be further explained with reference to an embodiment depicted in the drawing, wherein:

Fig. 1 shows details of the device according to the invention; and

Fig. 2 shows a perspective view of several devices combined to form an assembly according to the invention.

Fig. 1 represents an embodiment of the device according to the invention generally indicated by 1. It comprises a carrier 2, which, in a manner not shown here, is connected with a travelling device.

Near the end shown, the carrier 2 is provided with a hinge 3. Gripping jaws 4 and 5 respectively are freely rotatably mounted on hinge 3. Each jaw has a gripping end 6 and an mounting end 7. The gripping ends 6 are of oblong construction and their longit- udinal axis is indicated by 20. Jaws 4 and 5 are movable apart according to arrow 9. Each of the mounting ends is provided with a portion 13 bent outwards near its top side.

A pointed or tapered pin is referred to by 8. It is movable up and down in the direction of arrow 21. During a downward movement it will cause the jaws 4 and 5 to be forced apart. There is provided a spring 12 which opposes the separating force.

10 refers to a plant possessing a root portion 23 and a foliage portion 24.

Fig. 2 shows the assembly 11 obtained through combination of the device described with reference to Fig. 1. There is provided a beam 16 on which several devices 1 are mounted through carriers 2. A corresponding number of pins 8 project from another beam 26 and can be moved up and down by a pneumatic cylinder-plunger assembly 17. The frame (not shown) of this assembly can be moved both in horizontal direction 18 and in vertical direction 19.

14 is a first tray for plants and 15 refers to a second tray. In this example it is intended to transfer plants from e.g. tray 15 to tray 14.

For this purpose, the approach movement of the gripping ends 6 to the plants 10 according to the present invention is performed in the final portion of the path of travel such that the plants are approached from aside. As appears from Fig. 1, the plant is gripped on the part immediately above its root 23. In this place, seizure of the plant stalk is possible in the easiest way. The gripping force is determined by the closing force of the gripping ends 6 of the jaws 4 and 5, as determined by the spring force of spring 12. During the approach to the plants the jaws, especially the gripping ends 6, of course, will be moved apart by the downward movement of the pins, forcing the jaws to open.

Upon seizure of the plants by removing the pins 8, any desired movement, i.e. also a vertical movement in the direction of arrow 19, can be performed.

After the plants have been placed in the desired position in tray 14, the device is removed in relation to the plants by putting the pins 8 in between the gripping jaws 6, essentially moving in a horizontal direction, i.e. sideways.

According to the present invention it is possible to arrange two assemblys as shown in Fig. 2 opposite to each other, so that a tray 15 can be emptied row by row from two sides.

The present invention enables a row of plants to be gripped precisely and in an extraordinarily speedy manner, and to displace the plants without damaging them. Leaves, if present, do not lead to trouble.

The device described above may be used for plants of any size, whether or not having roots underneath, and whether or not these roots are provided with a substrate surrounding them, such as plant plugs.

Having read the above description, variants will immediately come to the mind of a person skilled in the art. They will be obvious and fall within the scope of the accompanying claims, explicitly seeking rights for variants falling within the scope of subclaims independent of the main claim.

Claims

1. Assembly (11) comprising a series of devices (1) placed side by side for simultaneously gripping a series of plants, as well as a container (14, 15) for said series of plants, said devices being arranged on a common support (16) displaceable relative to said container, each device comprising, two gripping jaws (4, 5) with gripping ends displaceable relative to each other, characterized in that said jaws are elongated jaws having a longitudinal axis (20) and that said support (16) is movable substantially along said longitudinal axis towards said container (18) for gripping said plants, said longitudinal axis being essentially horizontal.

2. Assembly according to claim 1 wherein the two gripping jaws (4, 5) rotationally movable in relation to each other and wherein said device comprises a operating mechanism (8) for moving said jaws, said gripping ends (6) being elongated and near the mounting end being hinged on a carrier (2), said operating mechanism comprising a pin-shaped part (8) which, near the mounting end, can be moved between said gripping jaws in order to move these gripping jaws in relation to each other.

3. Assembly according to one of the preceding claims, comprising spring means (12) to drive these gripping ends (6) towards each other.

4. Assembly according to one of the preceding claims wherein the gripping jaws comprise a common hinge (3).

5. Assembly according to one of the preceding claims wherein a gripping jaw (4) near the mounting end (7) is provided with a curvature (13) extending in the direction away from the opposite gripping jaw.

6. Assembly according to one of the preceding claims wherein the operating mechanism comprises a pneumatic cylinder-plunger device (17).

7. Method of gripping a series of plants comprising an approach operation to a series of plants by an device for gripping series of plants and, in the direction of approach, gripping them, characterized in that this approach comprises a sideways approach operation (18) in a direction essentially perpendicular to the extension roots-foliage of said plants.

8. Method according to claim 7, comprising the gripping of two series of plants arranged in adjoining places, said series being approached from opposite sides by said device for gripping plants.

9. Method according to claim 7 or 8, comprising the gripping operation of a series of plants, said plants having a first mutual distance, and placing said plants in a series at a second mutual distance, said second mutual distance being greater than the first mutual distance.

10. Method according to one of the claims 7-9 wherein said plants subsequently to being gripped are placed, said placement being effected at a higher level.

11. Method according to one of the claims 7-10, wherein said plants comprise plant plugs and the gripping of said plants takes place near said plant plugs.