The invention concerns the delivery and removal of plant-holders by a mobile belt conveyor system, which plant-holders are placed on a cultivation floor or removed from the cultivation floor. Such activities are performed for example in a greenhouse but may also take place outside.

Belt conveyor systems for transporting plant-holders over a cultivation floor are known. In a known belt conveyor system, a permanent conveyor belt device is arranged along a cultivation floor. One significant disadvantage of a permanent installation, as in the known system, is that this permanently takes up a part of the floor surface of the cultivation floor, whereby this floor surface can never be used for placing plant-holders thereon. Thus the floor surface of the cultivation floor may be used less efficiently. Another disadvantage of a permanent installation is that normally the system is only used a limited number of times per year, whereby bearings and other moving parts of such a fixedly erected belt conveyor have a reduced function after a relatively long period of stoppage. For these reasons, permanently installed belt conveyors in this sector are usually switched on every few days or every week without transporting plant- holders, in order to prevent the reduced function of the moving components as a result of stoppage. This leads to unnecessary actions and work for personnel, and energy consumption. A further disadvantage of such a permanently installed system is that excessive wear occurs on parts of the conveyor as a result of its exposure to water and fertilisers, which are required for optimum growth of the plants on the cultivation floor. A further disadvantage of such a permanently installed system is that it throws a shadow over the plants standing next to it. This then leads to unevenness in growth due to a difference in light exposure.

A known belt conveyor for a greenhouse is described in NL7908174. This belt conveyor comprises pivotably coupled frame parts and a single endless conveyor belt. The one belt is arranged along the top sides and undersides of all frame parts. The frame parts are attached to a tube of a greenhouse which runs high above the ground. In order to make this system active, all frame parts must be unfolded into their horizontal state and the belt must then be tensioned.

The object of the invention is to enable an effective delivery and removal of plant-holders by a mobile belt conveyor system for transporting plant-holders, such as for example in a greenhouse. This object is achieved according to the invention by a method according to claim 1 for the delivery of plant-holders to a cultivation floor or for the removal of plant-holders from a cultivation floor, wherein a belt conveyor system is used.

A possible advantage of the use of the belt conveyor system according to the invention is that no - or only a limited - permanent transport infrastructure need be present on the cultivation floor for delivery of plant-holders to be placed on a cultivation floor, and for removal of plant- holders placed on a cultivation floor. Because of the absence of a permanent transport infrastructure, for example, the entire surface of the cultivation floor may be used for the cultivation of plants placed in plant-holders. This leads to a higher yield and improved efficiency per surface unit of the cultivation floor. Also, the layout of the cultivation floor is flexible with the use of a belt conveyor system according to the invention.

Another possible advantage of the use of a belt conveyor system according to the invention is that the reach of the belt conveyor system can be chosen selectively according to the current situation. Because the elongate frame parts can be unfolded in a selected number, the length can be selectively set. It is possible, for example, to unfold half the number of frame parts for the delivery or removal of plant-holders.

A method for delivering plant-holders to a cultivation floor, using a mobile belt transport system as described herein, comprises the steps of:

- arranging the mobile belt transport system with the belt conveyor in the folded state next to the cultivation floor,

- bringing the belt conveyor into an at least partially unfolded state, wherein at least enough frame parts are unfolded to be able to transport the plant-holders to a desired location on the cultivation floor,

- setting the drive system in operation for driving the plurality of endless belts such that the movement direction of the endless belts is away from the frame base,

- placing plant-holders on the belt conveyor, whereby these are transported to the cultivation floor.

During use, the movable frame of the belt conveyor system is moved, for example, over a path of a plant cultivation location such as a greenhouse, and on this path comes to stop next to a field of the cultivation floor. The field of the cultivation floor often runs, with respect to the longitudinal direction of the path, in a transverse direction thereto such as perpendicular thereto.

Usually, the cultivation floor is completely filled with plant-holders during the plant growing process. In some cases, before the elongate frame parts are unfolded, a track must be cleared by moving the plant-holders or by manually removing a first row of plant-holders from the cultivation floor so as to create space on the cultivation floor for the belt conveyor to be unfolded.

In possible embodiments, the range of the elongate frame parts, measured in a length direction of the field, in unfolded state, is precisely as large as the length of the field, but it is also possible that the range of the belt conveyor is greater or smaller than the length of the longest field, and that in some cases not all elongate frame parts are unfolded.

During use of the system according to the invention for removing plant-holders and plants, the plant-holders are then taken from the field of the cultivation floor and placed on the belt conveyor so that the plant-holders from the cultivation floor can be transported away from the cultivation floor.

During use of the system according to the invention, when placing plant-holders on a cultivation floor, the method for use of the belt conveyor system is largely the same as for the removal of plant-holders, with the difference that the endless belts are driven in an opposite direction with respect to use during removal of the plant-holders. In other words, if the endless belts run in the inbound direction during harvesting, the endless belts run in the outbound direction when placing plant-holders. When placing plant-holders on a cultivation floor, the plant-holders are placed from a position next to the field, close to the mobile unit, onto the endless belts so that the plant-holders can be transported from a position next to the cultivation floor, onto the cultivation floor.

A method for removing plant-holders from a cultivation floor, using a mobile belt transport system as described herein, comprises the steps of:

- arranging the mobile belt conveyor system with the belt conveyor in the folded state next to the cultivation floor,

- bringing the belt conveyor into an at least partially unfolded state, wherein at least enough frame parts are unfolded to be able to transfer the plant-holders, placed on the cultivation floor, from their location on the cultivation floor onto the endless belts,

- setting the drive system in operation for driving the plurality of endless belts such that a movement direction of the endless belts is towards the frame base,

- placing plant-holders on the endless belts, whereby these are removed from the cultivation floor.

In a suitable embodiment, a possible advantage of the use of the belt conveyor system according to the invention is that little time is lost in necessary maintenance or replacement of parts. In a suitable embodiment, a frame part which must be maintained or replaced can easily be removed from the belt conveyor system, where necessary replaced, after which the belt conveyor system is ready for use again for delivering or removing plant-holders while the removed frame part is being maintained. This increases the efficiency of the system. For example, several, for example all, of the pivotable transport sections are identical in construction and can be coupled together in any order.

The plant-holders may be separate pots, for example made of plastic, wherein a single plant is growing in each pot, but the invention is also for example, in a suitable embodiment, applicable to the use of trays, for example trays of the type wherein each tray has several cavities which are filled with cultivation substrate, for example potting compost, as is usual for example in the cultivation of strawberries, or trays in which several separate pots are received.

During cultivation, the plant-holders stand on the cultivation floor. For example, the plant- holders stand on a water-permeable top cover of a porous floor construction, for example in an installation with an ebb/flood system.

A possible advantage of the invention is that, because the endless belts are tensioned on guides of the associated frame part, the belt conveyor system can be actuated as soon as the selected number of sections has been brought into the actively unfolded state. As a result, the system can also be used when the belt conveyor is not completely unfolded. The system therefore has a flexible range.

It is possible to use the belt conveyor in the at least partially unfolded state for removing plant- holders from a field of a cultivation floor, or for placing plant-holders on a field of a cultivation floor. The belt conveyor can then be brought into its folded state. If then plant-holders must be removed from or delivered to another field, the belt conveyor system is moved to the other field and again brought into the at least partially unfolded state in order then to remove plant-holders from this other field or place plant-holders on this other field. Then the belt conveyor can be returned to a folded state and moved to a further field, etc. Initially, a grower can thus manage with one or a few of these belt conveyor systems for enabling transport for a large number of fields. Also, a field need not be physically separated from another field; in the context of this invention, a field may also be a part of a larger cultivation floor without delimitation of the actual field. The belt conveyor need not be unfolded completely or to the same extent each time. Depending on the size of the field and the desired distance over which the plant-holders must be transported, the belt conveyor can be unfolded to a greater or lesser extent.

The use of a belt enables plant-holders to be transported relatively quickly. Preferably, the plant-holders in the form of separate pots stand behind one another on a relatively narrow belt during transport via the belt, so the belt width can remain small, for example between 4 and 15 centimetres. In situations where trays are used for cultivation, or where pots are first placed in trays and then the trays transported via the belt, the belt may be adapted to the size of the trays, for example 30 to 50 centimetres wide.

A frame part according to the invention is, for example, between 1.50 and 4 metres long, preferably between 2.50 and 3.50 metres long.

Depending on whether the system is used for transporting plant-holders or trays, the frame parts may, for example, be 20 to 30 centimetres wide, or 55 to 65 centimetres wide.

It is conceivable that a further conveyor belt is used in combination with a belt conveyor system according to the invention, which further conveyor belt, close to the movable frame base, adjoins the belt of the belt conveyor system according to the invention, and which further conveyor belt is, for example, used to transport the harvested plant-holders from a location next to the field of the cultivation floor to a central location; for example, this may take place in a manner already known in the sector, or by means of a second belt conveyor according to the invention which runs along a field of the cultivation floor, for example transversely or perpendicularly to the belt of the belt conveyor system which is arranged in the field of the cultivation floor. The transfer of plant-holders between the belt and another conveyor may take place automatically if desired. During harvesting, the other conveyor, for example the other belt, may transport the plant-holders to a (temporary) processing area. The plant-holders may be automatically moved from the belt of the system according to the invention to another belt or conveyor which transports the plant-holders to such a (temporary) processing area.

The belt conveyor systems may be used for example to remove plant-holders, i.e. to transport plant-holders from a field of a cultivation floor to a location next to the cultivation floor. During removal, the plant-holders are placed on the inbound active part of the belt. The belt conveyor system may also be used to place plant-holders on the field of the cultivation floor. In this case, the plant-holders are placed on the outbound active part of the belt, whereby they are moved from a location next to or outside the field into the field of the cultivation floor.

A possible advantage of the use of the belt conveyor system according to the invention is that the system as a whole is movable from a storage position to the cultivation floor. In the storage position, the belt conveyor system is preferably protected from harmful environmental factors such as moisture, salts from rainwater, water etc., and in the storage position preferably little wear occurs to the belt conveyor system. When the cultivated plants are ready to be harvested or moved to another field (for example in another greenhouse), the belt conveyor system may be brought out of storage and put into use, and after use the belt conveyor system can be returned to a storage state and stored at the storage location. The belt conveyor system also offers the possibility of being placed in different, separate harvest fields. This is in contrast to a fixed permanent installation.

The invention may be used both in a greenhouse and outside. When used outside, open to weather and wind, it is an advantage of the system that, in a suitable embodiment, the transport takes place closely above the cultivation floor, whereby the plant-holders standing on the belt are effectively protected from wind by other plant-holders still standing on the cultivation floor. Elongate frame parts may for this reason, in unfavourable wind conditions, be deliberately moved into the lee of other plant-holders on the cultivation floor, in order to prevent the wind from blowing over the plant-holders standing on the belt.

As stated, the belt conveyor system comprises a movable frame base. Movable in the context of the present application means that the movable frame base can be moved easily. For this, the movable frame base may,, for example comprise wheels so that the frame base can travel for example through a greenhouse and over the paths of the greenhouse. These wheels are, preferably, provided with a locking device so that the frame base is stable when the belt conveyor system is brought into use. Alternatively, a movable frame base need not have wheels or similar, and may for example be movable by a forklift truck or pallet truck.

The belt conveyor system according to the invention comprises several elongate frame parts which each comprise a tensioned endless belt. Two adjacent frame parts in unfolded state make it possible for a plant-holder to be transferred from an endless belt of the one frame part to the endless belt of the other frame part via the endless belts. As soon as a plant-holder reaches a first guide roller of the frame part, this plant-holder is automatically transferred to the endless belt of the adjacent frame part. In this way, the endless belts of unfolded frame parts effectively serve as a longer endless belt.

The plurality of elongate frame parts are each coupled together so as to be pivotable in series about a horizontal pivot axis. A first of the frame parts is pivotably coupled to the movable frame base, and the following frame parts are each pivotably coupled to a preceding frame part. This effectively gives a chain structure of elongate frame parts. The elongate frame parts may thereby be unfolded from the folded state, and folded up again from the unfolded state. This makes the system flexible in use.

In folded state, the folded frame parts stand upright and their top sides and undersides face one another directly. Thus in fully folded state, the system has a relatively small footprint. The folded frame parts are supported by the movable frame base such that the plurality of frame parts can be moved with the movable frame base. In the unfolded state, the underside of the unfolded frame parts faces the cultivation floor.

For example, the unfolded frame parts lie with their underside directly on the cultivation floor, or wheels and/or feet are provided which protrude below the frame parts and rest on the cultivation floor.

In another solution, first an elongate strip of plates is laid on the cultivation floor, where applicable with a channel profile with a lower base part and upright side edges on which the frame parts come to rest, and then the frame parts are unfolded and laid on the strip of plates. The plates may, for example, be plate planking which is used for transport trolleys in horticulture.

The at least one motor of the drive system according to the invention is, for example, an electric motor or an internal combustion engine. One advantage of an electric motor is that it does not require fuel and continues to work as long as power is supplied. Also, an electric motor is usually quieter than an internal combustion engine. An advantage of an internal combustion engine is that a system with an internal combustion engine need not be connected to a power supply. The system may therefore be more mobile.

In some embodiments, the motor of the drive system is located in the frame base and the drive system comprises transmission means for transmitting drive power between the motor and the plurality of endless belts.

The transmission means comprise for example a belt which extends from the first to the second end of the frame part and drives at least one of the guide rollers of the frame part.

For example, a motor located on the frame base drives a first wheel, for example a toothed wheel, which is present at the first end of the first frame part. The first wheel then in turn drives the belt, which extends in the longitudinal direction to the second end of the frame part. For example, a second wheel is provided there, for example a toothed wheel, which drives a second guide roller of the belt of the frame part. The belt is then driven by the motor, whereby the guide roller and hence the endless belt is driven. A further transmission means, for example with a short further belt and/or intermeshing toothed wheels, transmits drive power to the adjacent frame part which may be provided with a similar belt transmission for driving its belt.

For example, the transmission means comprises several belts. In this example, one or more belts are tensioned between the first and the second guide rollers of a frame part, and one or more belts are tensioned between guide rollers of adjacent frame parts. In this example, the motor drives a guide roller, whereupon this drives the following guide rollers by means of the belts.

For example, the transmission means comprises one belt which is tensioned between several, for example all frame parts. In this example, the motor drives the single belt which then drives the running belts of the plurality of frame parts.

The transmission means may also consist of mechanical transmission means, for example comprising toothed wheels and/or chains. A guide roller of one frame part may thus be coupled to a guide roller of an adjacent frame part. Other possible embodiments of the guide means are possible.

In one embodiment, the transmission means connects a single motor to all endless belts, whereby a single motor can drive all belts. Thus said motor can be arranged in the frame base. This has the advantage that less maintenance is required and the motor is easy to access.

In an alternative embodiment, the motor of the drive system is located in a frame part, for example the first frame part, and the drive system comprises transmission means for transmitting drive power between the motor and the plurality of endless belts.

The transmission means of this embodiment may be the same transmission means as those from the embodiment in which the motor is located in the frame base. The transmission means are configured to transmit the drive power between the plurality of endless belts, and to keep the connection between the frame parts pivotable. In this embodiment, the transmission means for example comprises one or more belts, chains or toothed wheels.

One advantage of this embodiment is that no complex connection is required between the base frame and the first frame part. Thus the base frame can be detached from the frame parts relatively easily, for example for maintenance or replacement of the base frame. A further advantage of this embodiment is that it is also possible to move the frame parts with the base frame to a cultivation floor where the frame parts are unfolded. The unfolded frame parts may then be detached from the base frame, after which the base frame may be used again for transporting other frame parts.

In an alternative embodiment of the invention, the drive system comprises several motors and each frame part is equipped with a motor of the drive system for driving an endless belt belonging to the respective frame part. The motors for example drive one of the guide rollers in a frame part. These then rotate and drive the endless belt. In this embodiment, the motors are arranged for example in a guide roller. This gives a compact system and no extra space need be created in the frame part for accommodating the motor. In another embodiment, the motor may be arranged next to the guide roller.

In another embodiment, the motors drive the endless belts in another fashion, for example by means of a third guide roller arranged between the first and second guide rollers, or by means of another type of transmission system, for example via a toothed wheel which acts on the endless belt.

It is possible that a grower uses the system according to the invention for arranging a temporary belt conveyor system in a greenhouse. In this case, it is possible that a plurality of endless belts are used, and that for example two belts are placed in a T-shape. In this case, it is advantageous that the endless belts of the horizontal bar of the T -shape run in two directions, so that for example plant-holders which are placed on the running belts are transported from both directions towards the foot of the T. In the present embodiment of the invention, this can easily be achieved. For each frame part, the direction of the running belts can easily be determined by the corresponding motor which drives the one side or the other. The invention in this embodiment is therefore advantageous and versatile.

In some embodiments, the first frame part is removably coupled to the frame base. Thus the chain of frame parts can easily be detached from the frame base and for example laid on the cultivation floor. This has the advantage that a temporary belt conveyor is arranged on the cultivation floor without the movable frame needing to be present, for example if the motor(s) are integrated in one or more of the frame parts.

In some embodiments, the endless belts of frame parts in folded state are not driven at that moment. For example, this is ensured by selectively actuating motors, in embodiments in which each frame part is equipped with a motor, or by selective transmission of drive power by the transmission means, in embodiments with transmission means.

In some embodiments in which the motors are located in the plurality of frame parts, the system may be configured such that the motors can only be actuated when the corresponding frame parts are in the active state. These embodiments are possible because the plurality of frame parts each tension an individual endless belt. In this way, it is possible to actuate some of the endless belts and keep some switched off.

For example, the transmission means may be connected to a guide roller to be driven such that no power is transmitted if the corresponding frame part is in a substantially vertical state, and force is transmitted when the corresponding frame part is in the active state.

In some embodiments, adjacent frame parts are pivotably coupled by means of coupling pieces which are arranged between the adjacent frame parts. Preferably, the coupling pieces comprise wheels for supporting the plurality of frame parts and enabling them to travel over the cultivation floor during unfolding and folding.

The coupling pieces comprise for example double hinges which are arranged between adjacent frame parts. The coupling pieces are preferably elongate coupling pieces. The coupling pieces may make it easier to hold the frame parts in foldable state. When two adjacent frame parts are in folded state, oriented substantially vertically, the coupling piece may be oriented substantially horizontally and extend between the ends of the horizontal frame parts. In this way, a small gap may be left between the frame parts in vertical state, whereby if the endless belts are actuated, there is no chance that the endless belts will rub together and hence cause unnecessary friction.

In some embodiments, the coupling pieces comprise wheels for supporting the plurality of frame parts and enabling them to move between the folded and unfolded state. The wheels preferably protrude in the direction of the cultivation floor. This embodiment is advantageous because in this embodiment, the frame parts can easily be moved over the cultivation floor. This makes folding and unfolding the system easier. Instead of wheels, it is for example also possible that the coupling pieces are equipped with sliders for sliding the frame parts over the cultivation floor.

In some embodiments, the system is equipped with coupling pieces, and transmission means are arranged in the coupling pieces for transmitting drive power to all belts. In one embodiment of the invention, the transmission means comprise belts which are arranged in coupling pieces between guide rollers of adjacent frame parts.

In some embodiments of the invention, the plurality of frame parts comprise handles. The handles are placed, for example, on a side edge of the plurality of frame parts. The handles offer a user, for example a grower, a way of handling the plurality of frame parts manually. For example, using a handle, a frame part can be brought from a folded state to an unfolded state. The handles may also be attached removably to the plurality of frame parts. For example, the handles comprise a click-fastening system whereby the handles can be coupled to a frame part. In this way, a grower can successively couple a handle to a frame part, handle the frame part, detach a handle and then couple the handle to a following frame part.

In some embodiments, the plurality of frame parts comprise one or more ridges which protrude upward from the frame part relative to the active part of the endless belt. The ridges may for example be formed by raised side edges of the frame parts, so that the top side of a frame part in cross-section substantially forms a channel through which the active part runs. For example, the frame part has an H-shaped cross-section. Preferably, the one or more ridges extend over the complete length between the first end and the second end, but it is also possible that the ridges do not extend over the complete length of the frame part.

Preferably, the ridges form an edge which ensures that a plant-holder situated on the active part of the belt cannot fall off the belt during transport. The ridges ensure that the plant-holder remains on the belt. In suitable embodiments, it is a further possible advantage that, in folded state, the endless belts of adjacent frames do not touch one another. This is advantageous for example when all endless belts are driven by the drive system and only some of the belt conveyor sections are in the active state while the remainder are still folded up.

In some embodiments, the frame parts each comprise a belt guide which is erected below the active part of the endless belt. The belt guides consist for example of a stationary plate. This ensures that the plant-holders are supported in stable fashion and the endless belt cannot rub on itself, which could lead to extra wear. The latter is possible for example if a heavy plant- holder is placed on the endless belt. The belt guides may also consist of extra guide rollers over which the active part of the endless belt is guided.

In some embodiments, the endless belts are tensioned by the first and second guide rollers, for example by one of the two being adjustable in the longitudinal direction. In this embodiment, no extra tensioning means are required for tensioning the endless belts. This has the advantage that the frame parts are simpler than if they must be equipped with extra tensioning means.

In some embodiments, the frame parts of the belt conveyor sections have protruding wheels on the underside for enabling the frame parts to move over the cultivation floor between the unfolded state and the folded state. An advantage of these embodiments is that the frame parts can easily be moved over a cultivation floor. For example, when folding up the frame parts, these must be moved over the cultivation floor in the direction of the frame base. If the frame parts were to scrape over the cultivation floor, the cultivation floor could be damaged. Fitting wheels to the underside of the frame part prevents this problem. A further advantage is that it takes less force to move the frame parts over the cultivation floor, and hence - as preferred - manual folding and unfolding of the belt conveyor becomes possible.

In some embodiments, the plurality of frame parts comprise feet, for example extendable feet, for supporting the frame parts in unfolded state, which feet may or may not have wheels. The feet are attached for example to a side edge of the frame parts. One advantage of this embodiment is that the frame parts and hence the endless belts may be placed at a specific height, for example an ergonomic height, above the floor surface. In this way, it is more advantageous for a grower to place plant-holders on the endless belts or collect them from the endless belts because the grower need not bend down as far.

Preferably, all frame parts of the pivotable belt conveyor sections have the same length.

For example, the length of each of the frame parts of the pivotable belt conveyor sections is between 1.50 and 4 metres, preferably between 2.50 and 3.50 metres, preferably 3 metres.

In some embodiments, the mobile belt conveyor system comprises more than 10, for example more than 20, for example between 24 and 36 elongate frame parts. The belt conveyor system according to the invention may comprise a number of frame parts depending on the usable reach which is necessary when cultivating plants. For example, for a cultivation floor with a length of 90 metres, and using frame parts each with a length of 3 metres, 30 frame parts are necessary to be able to extend the belt conveyor system over the full length of the cultivation floor.

In some embodiments, the mobile belt conveyor system comprises suspension means for suspending the mobile belt transport system, for example suspension means which are configured to suspend the base frame and belt conveyor of the mobile belt transport system on an overhead structure instead of placing the system on the ground. For example, it is provided to suspend the system on an overhead structure such as a horizontal guide rail, for example formed by a tube. This may be present for example in a greenhouse, for example a tube for heating or ventilation of the greenhouse. The suspension means comprise for example bars on which the frame parts, and in some cases the base frame in unfolded position, can be suspended. The suspension means may for example also comprise belts or chains. The suspension means may also be attached to fixing means specifically provided for this on a roof of the greenhouse or, if the system is used outside, on a frame erected for this over the cultivation floor. These embodiments make it possible not to place the system on the cultivation floor, but suspend it above the cultivation floor. In this way, the footprint of the system on the cultivation floor is practically nil, and the cultivation floor can at all times be fully used for placing plant-holders. Furthermore, with a suitable embodiment, the grower need not bend down as far to place a plant-holder on or collect it from an endless belt.

The system may for example be used by bringing the system with belt conveyor in folded state to the cultivation floor. Then the complete system is suspended by attaching the suspension means to the base frame. For this, the system must be lifted from the floor. Then the elongate frame parts can be unfolded and suspended with the corresponding suspension means. When folding and storing the system, the process may be performed in reverse order. The invention furthermore concerns a mobile belt conveyor system as described herein which is or may be placed on the cultivation floor.

The invention furthermore concerns a cultivation floor in combination with a mobile belt transport system as described herein, wherein for example the cultivation floor is provided with a water-permeable and horizontal top layer, wherein the top layer comprises a top cover, which top cover is configured for plant-holders to be placed thereon, wherein the cultivation floor preferably comprises one or more layers of granular material below the top cover.

The belt conveyor system according to the invention is ideally suited for use in combination with a cultivation floor which is provided with a water-permeable construction, for example with a water-permeable top cover on which the plant-holders stand. This type of cultivation floor may be configured with a so-called ebb/flood watering system for watering plants which are arranged in plant-holders and placed on the cultivation floor.

The invention furthermore concerns a belt conveyor system as described herein, for example as described in the claims.

The invention furthermore concerns a method for harvesting/removing plant-holders from a cultivation floor, and a method for placing plant-holders on a cultivation floor.

The invention furthermore concerns an embodiment of the method according to the invention for delivering or removing plant-holders, wherein the plurality of frame parts in unfolded state are placed on the cultivation floor.

The invention will be presented in more detail in the following description, given with reference to the drawings in which:

Figure 1 is a side view of a belt conveyor system according to the invention, wherein the belt conveyor system is placed on a pallet truck;

Figure 2 shows an elongate frame part according to the invention;

Figure 3 shows a detail of an end of the elongate frame part from figure 2;

Figure 4 shows a plurality of frame parts coupled by means of coupling pieces;

Figure 5 shows a detail of a coupling piece from figure 4; and

Figure 6 is a top view of the system according to the invention in an at least partially unfolded state.

Figure 1 shows a side view of a belt conveyor system 1 according to the invention for delivering plant-holders to be placed on a cultivation floor and for removing plant-holders placed on a cultivation floor.

In this example, the belt conveyor system 1 is placed on a pallet truck, for example so that it can be moved to a cultivation floor. In other embodiments of the invention, the frame base 2 may be equipped with wheels so that a pallet truck is not necessary for moving the belt conveyor system 1 , for example from or to a cultivation floor. When the belt conveyor system 1 has arrived at the cultivation floor, it may be removed from the pallet truck. It is also possible that the belt conveyor system 1 remains on the pallet truck during use.

The belt conveyor system 1 comprises a movable frame base 2 and a belt conveyor with pivotable sections which each have an elongate frame part 3.

The figure shows for illustration only four elongate frame parts 3 which are all in a folded and substantially vertical state. In this state, the elongate frame parts 3 face one another with their top sides 7 and undersides 8. Thus the belt conveyor system 1 in fully folded state has a relatively small footprint.

When the belt conveyor system 1 is at a location for delivering or removing plant-holders, the frame part 3 may be brought from this folded position to an unfolded position by folding the frame parts 3 down one by one and bringing them out of the frame base. For example, the frame parts 3 are equipped with wheels to simplify unfolding and moving of the frame parts 3.

In other embodiments, the belt conveyor system 1 according to the invention comprises more than four frame parts 3. For example, the system may comprise more than 10 frame parts 3, for example more than 20 frame parts 3, for example 30 frame parts 3. The size of the frame base 2, in particular the length, may be adapted such that a desired number of frame parts 3 can be placed on the frame base 2.

The folded frame parts 3 are supported by the movable frame base 2 so that the plurality of frame parts 3 are movable with the movable frame base 2.

The frame base 2 comprises a support floor 2a on which the frame parts 3 stand upright in their unfolded state. At a height above the support floor, side supports 2b are arranged so that on a front side of the frame base, an open channel is formed in which the frame parts stand upright and are supported at the side. The first frame part is pivotably coupled by its first end to the frame base 2. An end support 2c serves as a stop for the vertical position of the frame part and also the further frame parts.

The belt conveyor system 1 furthermore comprises a drive system 11 comprising at least one motor 12 for driving the plurality of endless belts 4 which are tensioned in the plurality of frame parts 3.

The motor 12 in the figure is arranged on the frame base 2.

The motor 12, preferably an electric motor, drives the endless belt 4 of the first frame part 3 by choice in one of two possible directions. Transmission means 13 then transmit the drive power to adjacent frame parts 3.

The elongate frame parts 3 of the belt conveyor system 1 shown in figure 1 are coupled together by means of coupling pieces 14. The coupling pieces 14 are configured such that the frame parts 3 are pivotably coupled.

The frame parts 3 are equipped with handles 15 for handling the frame parts 3. In this embodiment, the handles 15 are arranged on the side edges of the frame parts 3.

The invention provides that, for delivering plant-holders to different cultivation floors and/or for removing plant-holders from different cultivation floors, the belt conveyor system 1 is moved each time to a following cultivation floor to be processed. Thus a grower need only have one or a few systems 1 to cover his transport needs.

If the system 1 is not being used, it is provided that the system 1 is stored, preferably in a shielded area, preferably in the folded position shown in figure 1. Thus when not in use, the system 1 is not exposed to harmful influences such as for example rain, ebb/flood, moisture etc. This applies in particular to the plurality of frame parts 3 and endless belts 4 of the system 1 which may be relatively vulnerable, for example in order to prevent corrosion, algae growth etc.

For example, the frame base 2 is provided with a control panel for controlling a drive of the endless belts 4, in some cases wirelessly. The frame base 2 may be equipped with a battery for the drive system 11. In other embodiments, the drive system 11 may be supplied with energy by a connection to an electricity network. In other embodiments, the system 1 may be driven by an internal combustion engine 12.

Figure 2 shows an elongate frame part 3 of the system according to the invention. This elongate frame part 3 is shown in isolation from the rest of the belt transport system 1, for example the frame part 3 is removed from the belt transport system 1.

The elongate frame part 3 is provided with a tensioned endless belt 4 on which plant-holders can be placed. The endless belt 4 makes it possible for the plant-holders to be transported relatively quickly. Preferably, the plant-holders in the form of separate pots stand behind one another on a relatively narrow belt during transport via the belt 4, so the belt width can remain small, for example between 4 and 15 centimetres. In situations where cultivation takes place with trays, or when pots are first placed in trays and then the trays transported by the belt 4, the belt may be adapted to the size of the trays, wherein the belts 4 are for example 30 to 50 centimetres wide.

A frame part 3 according to the invention is for example between two and four metres long, preferably between three and four metres long. Depending on whether the system 1 is used for transporting plant-holders or trays, the frame parts 3 may for example be between 20 and 30 centimetres wide or between 55 and 65 centimetres wide.

The elongate frame part 3 has a first end 5 and a second end 6. The endless belt 4 is supported by a first guide roller 9 and a second guide roller 10, which are arranged respectively at the first end 5 and second end 6.

In some embodiments, the guide rollers 9, 10 tension the endless belt 4, whereby the endless belt 4 is under sufficient tension to be able to carry the plant-holders on the active part of the belt.

The elongate frame part 3 furthermore has a top side 7 and an underside 8. The plant-holders are normally placed on the endless belt 4 on the top side 7 of the frame part 3.

In the folded state of the frame part 3, the top side 7 and underside 8 are arranged adjacent to and face towards a top side and underside of the adjacent frame parts 3. In the unfolded state of the frame part 3, the underside 8 of the frame part 3 faces towards the cultivation floor.

The frame part 3 in figure 2 comprises a handle 15 for handling the frame part 3. In some embodiments, it is possible that the frame part 3 furthermore comprises wheels 16 for moving the frame part 3.

If a plant-holder is moved via the endless belt 4 of the frame part 3 between the first end 5 and second end 6, at some moment this plant-holder will reach the second end 5. As soon as the plant-holder reaches the second end 5, the plant-holder is taken by the endless belt 4 of the adjacent frame part 3 in that the plant-holder moves off the endless belt 4 of the first frame part 3 and onto the endless belt 4 of the second frame part 3. Thus the endless belts 4 of unfolded frame parts 3 effectively serve as a longer endless belt 4. The elongate frame part 3 of figure 2 is coupled in series with a plurality of elongate frame parts 3 of the belt conveyor system 1. The frame parts 3 are thus connected such that they are each pivotable about a horizontal axis.

A first of the frame parts 3 is pivotably coupled to the movable frame base 2, and the following frame parts 3 are each pivotably coupled to a preceding frame part 3. In this way, an effective chain structure of elongate frame parts 3 is produced. A selective number of elongate frame parts 3 may be unfolded from the folded state and folded up again from the unfolded state. This makes the system flexible in use because the active length of the belt conveyor can quickly and easily be adjusted.

A coupling mechanism, such as for example hinges, for coupling the frame parts 3 is not shown in figure 2.

Figure 3 shows a detail of the elongate frame part 3 from figure 2. In particular, figure 3 shows a detail of the first end 5 of the elongate frame part 3 of figure 2, wherein the endless belt 4 is not shown. The first guide roller 9 normally supports the endless belt 4. In this embodiment, the first guide roller 9 is equipped with one or more toothed wheels 17, on which transmission means 13, e.g. a toothed belt, can be arranged for transmitting the drive power from the drive system 11 to an adjacent frame part 3. It is also possible that the toothed wheels 17 are used to transmit drive power to the guide roller 9 of an adjacent frame part 3 by transmission means 13, for example a belt. In the embodiment of figure 3, the first guide roller 9 is connected to the second guide roller 10 of the frame part 3 by an internal transmission means, for example a belt, which is arranged in the frame part 3. This increases the transmission of the drive power and makes it possible to transmit drive power without the need for the endless belt 4 to be set in motion. This would be the case if the endless belt 4 were to transmit the drive power between the first guide roller 9 and second guide roller 10.

Figure 3 shows a belt guide 18 in the form of a plate which guides the active part of the endless belt.

The belt guide 18 is arranged between the outbound part and the inbound part of the endless belt 4. This ensures that the endless belt 4 cannot rub on itself, which would lead to extra wear; this is possible, for example, if heavy plant-holders are placed on the endless belt 4.

Figure 4 shows a plurality of frame parts 3 coupled by means of coupling pieces 14, and figure 5 shows a detail of a coupling piece from figure 4. The frame parts 3 are shown in folded state. The coupling pieces 14 are arranged at the ends 5, 6 of the frame parts 3. As can be seen in the figures, the transmission means 13, which are arranged between the guide rollers 9, 10 of adjacent frame parts 3, comprise toothed belts. In figure 5, a part of the endless belt 4 has been omitted in order to show that a toothed belt is arranged on the guide roller 9, 10 and runs inside the elongate frame part 3 to the other guide roller 9, 10 in order to transmit drive power.

The elongate frame parts are provided with wheels 16. The wheels 16 protrude downward in folded state, as shown in figure 4. In this way, the elongate frame parts 3 can also easily be moved in the folded position. Thus the elongate frame parts 3 can more easily be bought from a folded position to an unfolded position.

As figures 4 and 5 show, the coupling pieces 14 are arranged on the elongate frame parts 3 at the guide rollers 9, 10, so that the elongate frame parts 3 pivot around the rotational axis of the guide rollers 9, 10. In this way, the endless belts 4 can run towards the end of elongate frame parts 3.

Figure 6 shows a top view of the system 1 according to the invention in at least partially unfolded state. This embodiment of the invention shows a number of frame parts 3 in unfolded state and a number of frame parts 3 in folded state.

In this state, the belt conveyor system 1 according to the invention can transport plant-holders over the unfolded frame parts 3. It is also possible to unfold and fold up more frame parts 3.

The frame base 2 is erected on a floor, for example on a path next to a cultivation floor.

In one embodiment, the drive system 11 comprises for example several motors 12 which are arranged in the frame parts 3 in order to drive each frame part 3 separately.

The invention furthermore concerns a method for harvesting/removing plant-holders from a cultivation floor, and a method for placing plant-holders on a cultivation floor.

A method for delivering plant-holders to a cultivation floor, using the mobile belt transport system, comprises the steps of:

- arranging the mobile belt conveyor system 1 with the belt conveyor in the folded state next to the cultivation floor,

- bringing the belt conveyor system 1 into an at least partially unfolded state, wherein enough frame parts 3 are unfolded to be able to transport the plant-holders to a desired location on the cultivation floor,

- setting the drive system 11 in operation for driving the plurality of endless belts 4, such that a movement direction of the endless belts 4 is away from the frame base 2,

- placing plant-holders on the endless belts 4, whereby these are transported to a remote part of the cultivation floor.

During use, the movable frame base 2 of the belt conveyor system 1 travels for example over a path of a greenhouse, and on this path comes to stop next to a field of the cultivation floor. The field of the cultivation floor often runs, relative to the longitudinal direction of the path, in a transverse direction thereto, such as perpendicular thereto.

Usually, during the plant growing process, the cultivation floor is completely full of plant- holders. In some cases, before the elongate frame parts 3 are unfolded, a track must then be cleared by moving the plant-holders, or by manually removing a first track of plant-holders from the cultivation floor so as to create space on the cultivation floor for the elongate frame parts 3.

During use of the system according to the invention, in the removal of plant-holders from a cultivation floor, the method for use of the belt conveyor system 1 may be almost the same as for the delivery of plant-holders, with the difference that the belts 4 run in an opposite direction relative to their use during delivery of plant-holders. In other words, when the endless belt 4 has an inbound direction during harvesting, the endless belt 4 has an outbound direction during placing of plant-holders. When placing plant-holders on a cultivation floor, the plant-holders are moved from a position next to the field onto the endless belts 4, so that the plant-holders can be transported from a position next to the cultivation floor onto the cultivation floor.