EP4637319A1

EP4637319A1 - Agricultural machine for vegetables harvesting with optimized filter

Info

Publication number: EP4637319A1
Application number: EP22854519.0A
Authority: EP
Inventors: Francesco ROSELLI; Alberico Durso
Original assignee: Dari Ecomeccanica Srl
Current assignee: Dari Ecomeccanica Srl
Priority date: 2022-12-21
Filing date: 2022-12-21
Publication date: 2025-10-29
Also published as: WO2024134253A1

Abstract

Motorized vehicle for agricultural use, comprising four wheels, at least two of which being steering wheels, and a driving seat, and also comprising a device for cutting and harvesting leaf vegetables or the like, provided with a harvesting tank (7), comprising a cutting device (2) and a sucking system for the cut leaves, said sucking system comprising : a horizontal sieve means (9), configured to divide the volume of said tank in a first upper portion (71) to said sieve means (9) and a second lower portion (72) to said sieve means, said sieve means extending along the whole horizontal section of said tank (7); a centrifugal fan (11) arranged in said lower portion (72) of said tank (7) and configured to suck air from said deposit tank (7) and to expel it outside through a discharge duct (12); an air sucking duct (6) provided with a sucking mouth arranged at said cutting device (2), said tank (7) being hermetically closable, so that the sucked air by said fan (11) has to be necessarily sucked by said sucking mouth, to cross said upper portion (71) of said tank, to cross said sieve means (9) and so to be expelled through said discharge duct (12).

Description

AGRICULTURAL MACHINE FOR VEGETABLES HARVESTING WITH

OPTIMI ZED FILTER

TECHNICAL FIELD

The present invention relates to a machine for automatically harvesting leaf vegetables , such as for example rocket , lettuce , corn salad and the like .

State of the art

At the state of the art , machines for cutting and harvesting leaf vegetables are known .

These machines , in their embodiments known at the state of the art , comprise a cutting device installed in the front portion of a motori zed frame . At the rear of the cutting device a transportation device is provided, which conveys the cut vegetables towards the rear portion of the machine , where a box is provided for receiving the harvested vegetables .

These machines often use pneumatic transportation systems of the cut leaves , in which a centri fugal fan sucks air by means o f an aeraulic path which comprises a sucking mouth arranged at the cutting device , a transportation duct and a cylinder sieve . The cylinder sieve is arranged at the sucking mouth of the centri fugal fan and avoids that the harvested leaves are sucked by the fan, and so , are discharged outside . An embodiment known at the state of the art is shown in figure 1 . Other examples of such devices are described in documents CA2175540 , EP3560319 , US2954123 , GB2452240 ,

US2013167934 . In KR20090046025 i s described a cart for vegetables harvesting which sucks air through a tank arranged between the sucking mouth and the fan .

The tank is separated inside by a vertical partition wall , and inside the same tank a bag for gathering the cut leaves is arranged . This and other similar embodiments known at the state of the art are limited to be used for little harvesting volumes , since they need the provision of a gathering bag for the cut leaves (which, for practical reasons has to be of little dimensions , in order to allow its substitution when full ) , without which the system performance is sensibly reduced .

Moreover, when the bag is full , it obstructs the holes provided on the partition wall , thus limiting the sucking capacity of the device . As an alternative , in order to avoid this problem, the dimensions of the bag have to be sensibly less than the inner volume of the tank, thus limiting the useful volume for gathering the leaves . Technical problem

Regardless of the structural differences between the devices described in said documents, none of them has a harvesting device which exploits the whole surface of the top of the deposit box of the material as sucking surface.

Generally, in fact, all the devices known at the state of the art are provided with a sucking system of axial type, with the centrifugal fan arranged with its own axis in parallel to the advancement direction of the machine and a sieve, usually a bag sieve, arranged longitudinally to the vehicle as well .

Anyway, the limit of all the devices known at the state of the art consists in the fact that this kind of configuration is cumbersome, since a great part of the tank containing volume loses efficacy. Furthermore, another possible problem is the one linked to suck material greater than desired. In fact, in case of leaf vegetables harvesting, it is possible that leaves with greater dimensions, for effect of the depression created by the centrifugal fan, create a sort of grass layer which obstructs the sieve, thus making it difficult, if not impossible, to continue with the harvesting operations unless the machine is provided with a suitable sieve cleaning system .

Finally, it is to be noted that an architecture as the one used in the known art imposes a tortuous path on the sucked air inside the machine and this implies , from a thermodynamic point of view, loading losses which negatively influence the machine consumptions in the long run . Aim of the invention

Therefore , aim of the present invention is to provide a sucking device for leaf vegetables harvesters , which overcomes the limits linked to the embodiments known at the state of the art , and in particular which is not cumbersome inside the machine , so to allow a greater quantity of material to be harvested with equal dimensions of the machine , which is not subj ect to obstruction problems during harvesting operations and which does not require too complex operations for carrying out sieve cleaning .

Yet , the present invention provides a device configured so that the ducts forming the crop sucking system have such a configuration that a too tortuous path, which causes excessive loading losses , is not imposed on the sucked air . Therefore, the present invention provides a vegetables harvester, in which a sucking device with all the just described advantages is installed .

Brief description of the invention

The present invention realizes the prefixed aims since it is a device for cutting and harvesting leaf vegetables or the like, which can be installed on agricultural machines provided with a harvesting tank (7) , comprising a cutting device (2) and a sucking system for the cut leaves, said sucking system comprising: a horizontal sieve means (9) , configured to divide the volume of said tank in a first upper portion (71) to said sieve means and a second lower portion (72) to said sieve means, said sieve means extending along the whole horizontal section of said tank (7) ; a centrifugal fan (11) arranged in said lower portion (72) of said tank (7) and configured to suck air from said deposit tank (7) and to expel it outside through a discharge duct (12) ; an air sucking duct (6) provided with a sucking mouth arranged at said cutting device (2) , said tank (7) being hermetically closable, so that the sucked air by said fan (11) has to be necessarily sucked by said sucking mouth, to cross said upper portion (71) of said tank, to cross said sieve means ( 9 ) and so to be expelled through said discharge duct ( 12 ) . Description of the figures

Figure 1 shows an overall view of an agricultural machine comprising a device of the type known at the state of the art ; figure 2 shows a view of an agricultural machine according to the present invention; figure 3 shows a schematical section view of the sucking device . Figure 4 shows an axonometric view of the tank with some structural details .

Description of the invention

In the following, obj ect of the present invention is described the machine , stating firstly that it is a motori zed vehicle for agricultural use , comprising four wheels , at least two of which being steering wheels , and a driving seat , and also comprising a device for harvesting leaf vegetables or the like , in addition to a cutting device and a sucking system of the cut leaves provided with a centri fugal fan arranged with vertical axis , so orthogonal to the advancement direction of the vehicle , and with the sucking mouth of the fan configured to suck through the whole upper surface of the harvesting tank . It is to be specified that this measure allows to lower sensibly the center of gravity of the harvesting tank, since the fan wheel of the fan is arranged on a horizontal plane in the lower portion of the tank.

Even when the tank is full, the material filling the upper portion, by being made up of leaves, is sensibly lighter than the centrifugal fan.

Moreover, the just described arrangement of the fan allows the path of the sucked air to be optimized and so the loading losses to be reduced, to the advantage of the sucking efficiency of the leaves which, as known, depends on the air speed at the cutting area. Reducing the loading losses, with equal fan performance, increases the air flowrate and so its speed.

As it is shown in figure 1, the device comprises a frontal cutting area made up of a vegetable cutting blade (2) and its relative actuation system (4) .

The vegetables cutting blade is preferably arranged in the frontal portion of the agricultural machine, so that the axis of the blade is substantially horizontal, with the blade positioned grazing on the soil, at a distance from the soil equal to the desired cutting height, and preferably between 0.5 and 20 cm. Depending on the case, the sharpened side can be sawed or smooth.

At the cutting device a sucking mouth is provided, to which a material transportation duct (6) is connected, which has the function to convey the material cut by the blade (2) and sucked by the sucking mouth to the deposit tank (7) , which has preferably substantially the shape of a parallelepiped.

In parallel to the base of this latter one, at least a sieve means (9) is positioned, with extension equal to the whole section of the deposit tank ( 7 ) .

The sieve means is arranged along a horizontal section of the tank (7) and so divides it in an upper portion (71) and a lower portion (72) .

The sieve means, in a first embodiment, is made up of a metal net, whose meshes are suitably dimensioned not to let the leaves cut by the blade and sucked by the sucking mouth pass through. It is to be specified that it is not needed that the first sieve means has particularly pushing sieve properties, but it is sufficient that it is able to hold the cut vegetables leaves. Possibly, the device can comprise another sieve means, of the type known at the state of the art, arranged in the lower portion (72) of the tank (71) and configured to protect the fan (11) from powder and sediments of lower dimensions than the sieve capacity of the first sieve means (9) .

The sieve means (9) , other than what happens in the known machines, is not of basket type, but allows to exploit the whole surface of the top of the deposit tank (7) as sucking surface for the centrifugal fan. This allows a remarkable increase in loading capacity; in fact, in the machines which use basket type sieves, the provision of the sieve and other sucking elements allows to exploit only approximately half the tank volume. The arrangement of the sieve (9) , as it is described in the present invention, allows instead to exploit the whole volume of said tank, thus increasing remarkably the loading capacity of the machine.

It is to be specified that, as it is clear from the drawings, the sucking tube (6) is connected in the upper portion (71) of said tank (7) . In this way, when the fan (11) puts the tank (7) under depression, the air can be introduced only through the sucking mouth arranged at the cutting device, since the tank is hermetically closed, and since the sucking mouth is the only available. In order to make the harvesting operations easier, the deposit tank (7) is provided with a discharge door (8) , preferably fastened to the upper portion of the tank (7) , and with a tilting system (10) . The device comprises also in its lower portion a centrifugal fan (11) , directly connected with the deposit tank (7) , and provided with an air discharge system (12) .

The device comprises also a control console (5) , arranged at the driving seat, from which it is possible to control each single step of the harvesting .

After describing the elements of the device, it is now possible to describe its functioning.

Once the machine is arranged in the correct position for harvesting, the operator, by means of the control console (5) , actuates the cutting means arranged frontally and the centrifugal fan (11) .

The air flow generated by the fan (11) makes the harvested material go up along the transportation duct (6) , up to reach the inside of the tank (7) . The air will then continue its path by passing through the sieve (9) , arranged on the bottom of the tank (7) , and by going out finally from the discharge system (12) . Once the material cutting and harvesting operations are ended inside the machine , the operator, by always operating the control console ( 5 ) , can actuate the tilting system ( 10 ) , which will rotate the deposit tank ( 7 ) and will allow the material discharge .

With the j ust described device , it is obtained a system able to allow a greater quantity of material to be harvested in comparison with the ones provided at the state of the art , thanks to a di f ferent management of the inner volumes of the tank; moreover, the j ust described device is not subj ect to obstruction problems during harvesting operations which are typical of the devices known at the state of the art , and allows to simpli fy the cleaning operations remarkably since all the harvested material falls by gravity on the bottom of the deposit tank ( 7 ) , and is more easily removable .

Moreover, the sucking surface increase with equal volume , and the particular configuration of the sucking system, lead to an advantage in terms of reduction of sucking load losses , so with equal flowrate and pressure it is possible to use for the sucking fans with lower power, while maintaining the same ef ficiency of the machines provided at the state of the art, but reducing consumptions in the long run.

Yet, the use of the control console allows the maximum freedom and easiness of adjustment of the various parameters involved in the harvesting process .

With reference to figure 4, according to a preferred embodiment the device comprises also a motor (14) provided with eccentric masses (15) with respect to the rotation axis of said motor, fastened to said sieve means and configured to make said sieve means vibrate and shake, in order to avoid that damp leaves remain adhered thus obstructing it.

Moreover, preferably, said centrifugal fan (11) is actuated by the motor of the agricultural machine - both endothermic or electric - according to what described in the following.

The motor of the agricultural machine moves a main transmission shaft (17) , which is fastened both to a centrifugal clutch (18) and to the shaft of a three-phase asynchronous electric motor (19) .

The centrifugal clutch (18) controls in turn, when the rotation speed exceeds a minimum value, a toothed pulley configured to transmit - by means of a driving belt (20) - the motion to a secondary transmission shaft (21) which controls the rotation of the fan wheel of said centrifugal fan (11) .

In this way, until the rotation speed of the main transmission shaft (17) is lower than the minimum regime of rotation required by the centrifugal clutch to rotate the toothed belt (20) , power to the fan will not be transmitted and so this latter will be available at 100% only for the three-phase asynchronous electric motor, which in these conditions will behave as generator of electric energy which will be accumulated by suitable batteries .

While the number of revolutions increases, the gradual engagement of the centrifugal clutch occurs and so of the sucking fan of the system. In this way, the load due to the fan rotation, which the endothermal motor will sustain, will be ramped and a linear acceleration will be obtained, ideal for the rotations from the still condition of objects with high inertia, as the sucking fan.

In these conditions, it is provided a mechanic power both on the main shaft (17) , and so for the electric motor (19) , and ton he secondary shaft (21) or for the sucking fan, so dividing efficiently the total mechanic power of the endothermal motor. I f , instead, the asynchronous electric motor ( 19 ) behaves as motor instead of as generator, the described device provides the secondary shaft ( 21 ) with the sum of the mechanic powers coming from the motor and electric motor ( 19 ) .

The so described system is ideal for operating sucking plants which need continuous connections and disconnections , and it is above all able to level the energies required during the working cycle of the harvester machine .

In fact , when the motor of the harvester machine works in low regime , typically when it is still , the fan is still and the energy of the endothermal motor is accumulated in batteries , which instead will provide energy during the active step of the working cycle of the machine . The so described device allows to lower the average power required to the motor of the endothermal machine with equal performance of the sucking plant .

The present invention has been described according to a preferred embodiment , but equivalent variants are possible without departing from the protection scope of the invention .

Claims

1. Motorized vehicle for agricultural use, comprising four wheels, at least two of which being steering wheels, and a driving seat, and also comprising a device for cutting and harvesting leaf vegetables or the like, said vehicle being provided with a harvesting tank (7) , comprising a cutting device (2) and a sucking system for the cut leaves, said sucking system comprising: a horizontal sieve means (9) , configured to divide the volume of said tank in a first upper portion (71) to said sieve means (9) and a second lower portion (72) to said sieve means, said sieve means extending along the whole horizontal section of said tank ( 7 ) ; a centrifugal fan (11) arranged in said lower portion (72) of said tank (7) and configured to suck air from said deposit tank (7) and to expel it outside through a discharge duct (12) ;

- an air sucking duct (6) , connected to said upper portion (71) of said tank (7) and provided with a sucking mouth arranged at said cutting device (2) , said tank (7) being hermetically closable, so that the sucked air by said fan (11) has to be necessarily sucked by said sucking mouth, to cross said upper portion (71) of said tank, to cross said sieve means (9) and so to be expelled through said discharge duct (12) .

2. Vehicle for agricultural use according to claim

1, characterized in that the axis of said centrifugal fan (11) is orthogonal to the advancement direction of the vehicle.

3. Vehicle for agricultural use according to claim

2, characterized in that the sucking mouth of said fan is configured to such through the whole upper surface of the harvesting tank.

4. Vehicle for agricultural use according to one of the preceding claims, comprising also a cutting area provided with a vegetables cutting blade (2) and its relative actuation system (4) .

5. Vehicle for agricultural use according to one of the preceding claims, comprising also another sieve means arranged in the lower portion (72) of said tank (7) and configured to protect said fan (11) from powder.

6. Vehicle for agricultural use according to one of the preceding claims, characterized in that said vegetables cutting blade (2) is arranged with substantially horizontal blade axis, with position of the blade grazing on the soil, at a distance from the soil between 0.5 and 20 cm.

7. Vehicle for agricultural use according to one of the preceding claims, characterized in that the sieve means is made up of a metal net, whose meshes are suitably dimensioned not to let the sucked leaves pass through.

8. Vehicle for agricultural use according to one of the preceding claims, characterized in that said deposit tank (7) is provided with a discharge door (8) , fastened to the upper portion of the tank (7) , and with a tilting system (10) of said tank.

9. Vehicle for agricultural use according to one of the preceding claims, comprising also a motor (14) provided with eccentric masses (15) with respect to the rotation axis of said motor (14) , fastened to said sieve means and configured to make said sieve means vibrate and shake.

10. Vehicle for agricultural use according to one of the preceding claims, characterized in that said centrifugal fan (11) is actuated by the traction motor of said vehicle, which is configured to move a main transmission shaft (17) , in turn fastened to a centrifugal clutch (18) moving a toothed pulley configured to transmit, by means of a driving belt

(20) , the motion to a secondary transmission shaft

(21) which controls the rotation of the fan wheel of said centrifugal fan (11) when the rotation speed of said main shaft (17) exceeds a predetermined value.

11. Vehicle for agricultural use according to claim 10, comprising also a three-phase asynchronous electric motor (19) , integral to said main transmission shaft (17) and a battery pack, said electric motor being configured to charge said battery pack when the rotation speed of said main shaft (17) is lower than said predetermined value, and to provide with a torque said main shaft, when said rotation speed is higher than said predetermined value.