WO2025168415A1

WO2025168415A1 - Horticultural product conveyance unit

Info

Publication number: WO2025168415A1
Application number: PCT/EP2025/052233
Authority: WO
Inventors: Luca Benedetti
Original assignee: Unitec SpA
Current assignee: Unitec SpA
Priority date: 2024-02-05
Filing date: 2025-01-29
Publication date: 2025-08-14
Anticipated expiration: 2026-08-05

Abstract

A conveyance unit for horticultural products (A), comprising at least: – an alternating succession of first supporting elements (2a) and second supporting elements (2b), cyclically movable along a predefined path (B): each pair composed of a first element (2a) and the following second element (2b) forms an accommodation and conveyance seat (3) for a respective horticultural product (A), – rotation means (4) configured to impart to each element (2a, 2b), during its advancement along the path (B), a rotation about a respective main axis (C), which is substantially transverse to the path (B). The first elements (2a) have a different shape with respect to the second elements (2b) and the rotation means (4) are configured at least to impart the rotation to the first elements (2a) transiting along a first useful part (D1) of the path (B) and at least to impart the rotation to the second elements (2b) transiting along a second useful part (D2) of the path (B). The useful parts (D1, D2) are partially superimposed at a common portion (D3), so that at least one of them extends along the path (B) beyond the common portion (D3), for the rotation of a further respective element (2a, 2b).

Description

HORTICULTURAL PRODUCT CONVEYANCE UNIT

The present invention relates to a horticultural product conveyance unit and to the method thereof.

As is known, in the field of the packaging and distribution of fruit and horticultural products in general the use of at least partially automated plants or lines, designed and sized to carry out a plurality of operations and treatments on a specific type of horticultural product, is now widespread.

These plants are equipped with units or means for moving the horticultural products of interest, which move them along a predefined path to subject them to various treatments by stations and devices placed along said path.

The methods and technologies by which said units provide the movement depend first and foremost on the shape of the specific horticultural product that is to be conveyed, but they must also be designed to comply with the many requirements dictated by the specific treatments to which the product itself is to be subjected.

In particular, it is known to use conveyance units comprising a succession of rollers or other axially symmetrical elements, moved along the advancement direction and arranged with their respective longitudinal axes at right angles to said advancement direction. Each pair of consecutive elements forms a respective seat for a product, which may rest on said elements, remaining arranged above the interspace between them.

While advancing along the path, causing the two elements that support it to rotate about their respective longitudinal axes, each product can be made to roll on itself, for example in order to expose to a video camera or other electronic vision instrument located overhead the entire surface of said product, so as to acquire information about it in an optimal manner. Moreover, rolling may be imposed in order to arrange the product according to a specific orientation required by the downstream stations.

For this purpose, therefore, it is known to use ribbons, belts or other devices placed below the path of the rollers or elements: when each of them reaches the part of the path affected by the device, the latter causes its rotation (by friction, by meshing, or otherwise), which continues until the element leaves the aforementioned part.

However, such constructive solutions are not without drawbacks.

The above-mentioned known solutions, which actuate the rotation of the axially symmetrical elements, are unable to assure the simultaneous activation and/or closure of the rotation steps of the two elements of each seat. The early activation of the rotation step of one element with respect to the other and, more importantly, the early closure of the rotation step of the first one with respect to the second, make it impossible to control the position of the product supported by them, also in view of the variety of sizes and shapes that the products have. Rotation of only one of the two rollers could, for example, result in product slippage, with unpredictable consequences on the orientation assumed.

Such a limitation is therefore unwelcome: for example because the lack of control may compromise the optimal acquisition of information (needed for example for product grading) and/or the proper execution of treatments imparted by the downstream stations.

The aim of the present invention is to solve the problems described above by providing a horticultural product conveyance unit that ensures simultaneity of the activation and/or closing of the rotation step of the two elements that, in each seat, support a product.

Within this aim, an object of the invention is to provide a conveyance method that ensures simultaneity of the activation and/or closure of the rotation step of the two elements that, in each seat, support a product.

Another object of the invention is to provide a conveyance method that achieves simultaneity of the entire rotation step of the two elements that, in each seat, support a product.

Another object of the invention is to provide a conveyance method that achieves optimal control of the position of the products during the entire step of their rolling and in particular at the end of the latter.

Another object of the invention is to provide a conveyance method that makes it possible to acquire information fully about each conveyed product.

Another object of the invention is to provide a unit and a method that ensure high reliability of operation.

Another object of the invention is to provide a unit and a method that adopt a technical and structural architecture that is alternative to those of units of the known type.

Not least object of the invention is to provide a unit and a method that are easily obtainable starting from commonly commercially available elements and materials.

Still another object of the invention is to provide a unit and a method that are low in cost and of assured application.

This aim and these and other objects that will become better apparent hereinafter are achieved by a unit according to claim 1 and by a method according to claim 10.

Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of the unit and method according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a perspective front view of the unit according to the invention;

Figure 2 is a view, similar to Figure 1, of the unit without the supporting elements, to better show the configuration of the rotation means;

Figure 3 is a top view of the unit without the elements as in Figure 2;

Figure 4 is an axonometric elevated rear view of the unit of Figure 1;

Figure 5 is an axonometric view from below of the unit of Figure 1;

Figure 6 is a schematic lateral elevation view of some parts of the unit of Figure 1;

Figures 7 and 8 are schematic front views of the supporting elements and of the rotation means;

Figures 9 to 13 are schematic top views of an operating sequence of operation of the unit;

Figure 14 is a block diagram of the method according to the invention.

With reference to the figures, a conveyance unit for horticultural products A is generally designated by the reference numeral 1.

Usually, the unit 1 is designed to convey a specific type of horticultural product A, but it is nevertheless within the protective scope claimed herein that the same unit 1 may convey (at the same time or as a result of a production batch change) different types of products A. Moreover, it should be pointed out that the unit 1 can find use in relation to any horticultural product A (fruits, vegetables, garden produce, etcetera).

The unit 1 can be used in any context and for any purpose (for example, therefore, for any activity for the processing and handling of horticultural products A), without thereby abandoning the protective scope claimed herein.

In the present description, the terms “upstream,” “downstream,” and “upstream of’ and “downstream of’ are used (in accordance with common usage) in reference to the advancement direction and orientation imposed on the products A by the unit 1 (and identified with an arrow in some of the accompanying figures).

The unit 1 comprises at least one alternating succession of first supporting elements 2a and second supporting elements 2b which are cyclically movable along a predefined path B. In other words, therefore, the elements 2a, 2b are arranged one after the other along the path B so that each first element 2a is interposed between two second elements 2b, and vice versa. The elements 2a, 2b are preferably but not necessarily axially symmetrical.

Each pair composed of a first element 2a and the next second element 2b (i.e., the one directly downstream) forms an accommodation and conveyance seat 3 for a respective horticultural product A. In per se known ways, in fact, in an initial section of the unit 1, one product A at a time is placed at the interspace between two consecutive elements 2a, 2b, resting on the latter, and in this arrangement is moved downstream by the elements 2a, 2b, as the accompanying Figure 1 clearly shows, for example.

During their cyclic movement along the path B (and in particular along a section thereof that is typically but not necessarily straight and substantially horizontal), the elements 2a, 2b can thus convey the products A (from upstream to downstream) for a variety of purposes.

The movement of the elements 2a, 2b along the path B, as well as the deposition of each product A in their respective seat 3, can be achieved in any way, according to the technology that the person skilled in the art might deem most appropriate among those known in the field.

In particular, in order to ensure the placement of each product A only between a first element 2a and the second element 2b located downstream (and not also between a first element 2a and the second element 2b located upstream), several solutions can be used: the movement of the elements 2a, 2b can be synchronized with the movement of a feeder (of any type) located upstream, or one can interpose a device between the latter and the elements 2a, 2b that conveniently controls the deposition of the products A in the designated seats 3, allowing or inhibiting it as necessary. Manual placement of the products in the seats 3 is also not excluded.

Moreover, the unit 1 comprises rotation means 4 which are configured to impart a rotation to each element 2a, 2b about a respective main rotation axis C, during its advancement (as it advances) along the path B (along part of it, while conveying the products A). The main axis C (which coincides with the axis of longitudinal symmetry if the elements 2a, 2b are axially symmetrical) is substantially transverse to the path B (and preferably substantially horizontal and perpendicular to the latter).

As a consequence, since the products A rest on the elements 2a, 2b, rotation of the latter causes the former to roll on themselves, and this, as known, can be of interest in a variety of applications, one of which will be described hereinafter.

It should be noted that the choice to use only the pair formed by each first element 2a with the second element 2b located downstream as a seat 3 (in which to place a product A), and not also the pair formed by each first element 2a with the second element 2b located upstream, first of all allows to keep the products A mutually spaced apart and ensures that the rotation of each element 2a, 2b has an effect on only one overlying product A.

According to the invention, the first elements 2a have a different shape with respect to the second elements 2b: in greater detail, all the first elements 2a typically (not necessarily) have the same (preferably axially symmetrical) shape, which is different from the (preferably axially symmetrical) shape adopted by all the second elements 2b. Moreover, and taking advantage precisely of the different shape, the means 4 are configured at least to impart the rotation to those first elements 2a that transit along a first useful part Di of the path B and at least to impart the rotation to those second elements 2b that transit along a second useful part D₂ of the path B. The useful parts D D₂ are clearly identified in Figures 9- 13. The useful parts D D₂ partially overlap at a portion D₃ which is common (to the parts D D₂), also identified in Figures 9-13, so that at least one of them extends along the path B beyond the common portion D₃ (in the upstream and/or downstream direction) for the rotation of an additional respective element 2a, 2b (in addition to those transiting on the common portion D₃).

It is specified that the elements 2a, 2b are typically secured to the respective support with the possibility of free rotation about the axis C (optionally with solutions to ensure minimal resistance against occasional rotation) and rotation occurs indeed by virtue of the means 4.

In particular, in the preferred embodiment, the first part Di extends upstream beyond the common portion D₃ to impart the rotation of an additional first element 2a and the second useful part D₂ extends downstream beyond the common portion D₃ to impart the rotation of an additional second element 2b.

The different shape of the elements 2 a, 2b and the partial overlap of the useful parts D D₂ achieve the intended aim, as will become apparent hereinafter by describing the sequence of Figures 9-13, which shows the preferred solution introduced above, in which both useful parts D D₂ extend beyond the common portion D₃ (one upstream and the other downstream), and in which only the two elements 2a, 2b of a seat 3 and the respective product A have been identified, indeed to better clarify the logic of operation.

During its advancement, each second element 2b initially reaches that portion of the first part Di that does not overlap the second and thus does not begin to rotate (Figure 9). As advancement continues, as Figure 10 shows, the second element 2b reaches the second part D₂ (at the portion D₃ which is common to the two portions D D₂) and begins to rotate, but in the meantime the first upstream element 2a (the one that cooperates with the one just mentioned in forming a seat 3) has in turn reached the first portion of the first part Di and in turn begins to rotate.

Therefore, it has been shown that by making the first part D i extend upstream beyond the common portion D₃ (and by iterating the sequence described above for all the elements 2a, 2b cyclically in transit), first of all simultaneity of the activation of the rotation step of the two elements 2a, 2b that support a product A in each seat 3 is achieved.

As they continue their travel along the common portion D₃, both elements 2a, 2b of the same seat 3 continue to rotate.

In Figure 11, it can be seen that the second element 2b at the center of said figure rotates because it is still on the second part D₂ (it is still traveling along the portion D₃ which is common to the parts D D₂), while the first element 2a directly upstream (belonging to the same seat 3) rotates because it is on the first portion of the first part Di (and has by now reached the common portion D₃).

The common portion D₃ is abandoned first by the second element 2b, which however continues to rotate due to the action of the portion of the second part D₂ that does not overlap the first part and indeed extends downstream beyond the common portion D₃ (Figure 12); meanwhile, the first element 2a is still transiting along the first part Di (it is still traveling along the portion D₃ which is in common to the parts D D₂) and thus in turn continues to rotate.

The second element 2b stops its rotation when it permanently leaves the second part D₂, but in the meantime the first element 2a located upstream has in turn reached and abandoned the downstream end of the first part Di (of the common portion D₃) and so it too stops its rotation (Figure 13).

Therefore, it has been shown that by making the second part D₂ extend downstream beyond the common portion D₃ (and iterating the sequence described above for all the elements 2a, 2b cyclically in transit), simultaneity of the closure of the rotation step of the two elements 2a, 2b that support a product A in each seat 3 is achieved.

More generally, with the preferred embodiment shown in the accompanying figures, simultaneity of the entire step of rotation of the two elements 2a, 2b supporting each product A in a seat 3 is obtained.

This result is also achieved by virtue of the already noted choice to arrange products A only in seats 3 formed by a first element 2 a and by the second element 2b located downstream; in fact, any products A placed in the adjacent region of space (between a first element 2a and the second element 2b located upstream) would not see simultaneity of the steps of rotation.

In any case, the protective scope claimed here also comprises solutions in which only one of the useful parts Di, D₂ extends beyond the common portion D₃, in the upstream or downstream direction, so as to achieve, respectively, only the simultaneity of the activation of the rotation step or only simultaneity of the closure of the latter, as a function of the specific requirements, but achieving in any case the intended aim.

The ways in which the means 4 are able to impart the rotation in different useful parts D D₂ (taking advantage of the different shape of the elements 2a, 2b) may be any without abandoning the protective scope claimed herein.

In an embodiment of considerable practical interest that however does not limit the invention, the means 4 comprise at least one first transmission element 5a and a second transmission element 5b, which are arranged substantially side by side along respective closed imaginary curves (which are variously shaped) and are configured to engage (even in a per se known manner) with corresponding elements 2a, 2b (with corresponding points of contact or useful portions thereof) as they transit along the first useful part Di and along the second useful part D₂, respectively. In practice, therefore, the imaginary curve along which each transmission element 5a, 5b extends is arranged in such a way as to have a part which faces and is proximate to the path B.

The transmission elements 5a, 5b may be ribbons or belts (as in the accompanying figures) which engage the elements 2a, 2b by friction; they might also be chains which engage by meshing the elements 2a, 2b (provided in this case with toothed portions for example). However, further practical choices for the transmission elements 5a, 5b are not excluded.

Typically, the transmission elements 5a, 5b are arranged below path B of the elements 2a, 2b.

It is specified that the means 4 might also operate in the preset manner by resorting to a single instrument (instead of the two elements 5a, 5b), for example by resorting to a single deformable ribbon, similar in width to the sum of the elements 5a, 5b and associated with a device which, by means of idler pulleys or the like, translates when necessary toward the path B (and the elements 2a, 2b in transit) only some portion of said ribbon, which correspond indeed to the portion Di, D₂ of interest.

More particularly, with reference to the preferred embodiment, shown in the accompanying figures by way of non-limiting example of the invention, each transmission element 5a, 5b comprises a respective useful segment 6a, 6b that faces (in a parallel arrangement) the corresponding useful portion D D₂ of the path B and is configured to engage indeed corresponding elements 2a, 2b. As Figure 2 clearly shows, for example, the segments 6a, 6b are at least partially offset with respect to the advancement direction of the elements 2a, 2b along the path B. It should be noted that in practice it is precisely the placement of the segments 6a, 6b that identifies the placement of the parts D D₂: the offset of the former allows indeed to obtain the partial overlap of the latter, shown in the previous pages.

The placement of the segments 6a, 6b and in general the spatial configuration of the transmission elements 5a, 5b (the imaginary curve along which they extend) can be obtained by means of idler pulleys, wheels and similar guiding components 7 around which said transmission elements 5a, 5b can be wound, as indeed in the accompanying figures.

In the accompanying figures, the placement of the segments 6a, 6b is such that when the respective elements 2a, 2b reach the respective parts D D₂ rotation is obtained automatically, indeed because during transit the portions of interest of the elements 2a, 2b slide over the useful segments 6a, 6b. In any case, the elements 5a, 5b or at least the useful segments 6a, 6b can be given the possibility to move away and toward the path B of the elements 2a, 2b, so as to give the unit 1 the possibility to activate or deactivate the rotation of said elements 2a, 2b (and the rolling of the conveyed products A).

In both cases, the different shape of the elements 2a, 2b, and in particular the different profile of the sides, is used to actuate rotation in different useful parts D D₂.

Usefully, the means 4 can comprise a system 8 for the movement (translation or sliding) of the transmission elements 5a, 5b along the respective imaginary curves (preferably, with an adjustable speed). By making the elements 5a, 5b translate on themselves, it is evidently possible to change the rotation rate of the elements 2a, 2b and therefore the stresses imparted to the products A, as a function of the specific requirements.

However, keeping the transmission elements 5a, 5b stationary while still allowing rotation to occur upon contact with the elements 2a, 2b during rotation, is not excluded.

In particular, the movement system 8 may comprise a motor 9 which is provided with an output shaft 10; the transmission elements 5a, 5b may be wound around respective main pulleys I la, 11b keyed indeed on said output shaft 10, so as to receive motion from the motor 9 in order to be able to move on themselves along their respective imaginary curves. The main pulleys I la, 11b, moreover, cooperate with the other guiding components 7 in defining the spatial configuration of the elements 5a, 5b (the imaginary curves already mentioned).

The choice introduced above allows to use a single motor 9 for the movement of both transmission elements 5a, 5b, with benefits in terms of space and cost containment and structural simplification. However, it is not excluded (in fact, separate drive units can be provided for the two elements 5a, 5b if necessary) resorting to differently shaped movement systems 8, whether provided with a single motor 9 (otherwise connected to the elements 5a, 5b) or not. The elements 2a, 2b can be shaped in any way: for example, they could be rollers with a diabolo-like (or hourglass-like) shape, in which the first elements 2a are distinguished from the second elements 2b by the location (along the axis C) of the minimum cross-section.

In the preferred embodiment, illustrated in the accompanying drawings by way of non-limiting example of the invention, each element 2 a, 2b comprises at least (or is constituted by) two primary disks 12A, 12B (typically but not necessarily circular) of different diameter (or with different contours), which rotate integrally with each other and are coaxially aligned along the respective main axis C (about which indeed they can rotate integrally).

Moreover, a first major primary disk 12A has a larger diameter than the other minor primary disk 12B; the major disks 12A and the minor disks 12B are arranged so as to be mutually offset in the two elements 2a, 2b of the same seat 3. In other words, each major disk 12A of a first element 2a faces (aligned along the path B) the minor disk 12B of the second element 2b that cooperates with the former to support a product A in a seat 3, and vice versa.

This mutual arrangement allows indeed to give a different shape to the first elements 2a with respect to the second elements 2b (understood as the sum of the primary disks 12A, 12B that compose them) and to actuate their rotation in different useful parts D D₂ (which overlap only partially).

Usefully, in fact, the transmission elements 5a, 5b can engage the elements 2a, 2b precisely at the respective major disks 12A and at their edge in particular. In fact, as can be seen in particular from Figures 7 and 8, even a small difference between the diameters of the primary disks 12 A, 12B (arranged so as to be mutually staggered in the elements 2a, 2b of the same seat 3) is in fact sufficient to impart that different shape that is necessary for the purposes of the invention, i.e., to allow the transmission elements 5a, 5b to actuate their rotation in respective parts Di, D₂ that overlap only partially. Each element 2a, 2b could, moreover, comprise additional auxiliary disks 12C (aligned with the others): in the accompanying figures, in fact, each element 2a, 2b comprises a total of four disks 12A, 12B, 12C: the two auxiliary disks 12C of each element 2a, 2b are external to the others and have a larger diameter than the latter, so as to perform a useful function of transverse containment of the products A.

In an application of considerable practical interest, the unit 1 may comprise a vision system 13 (shown for the sake of simplicity only in Figure 1) configured at least to acquire information about each product A as it transits at least on the common portion D₃ of the useful parts Di, D₂. More specifically, the vision system 13 is typically configured and oriented so as to view each product A during the rolling consequent to the entire step of rotation of the two elements 2a, 2b that support it.

In particular, the vision system 13 may comprise one or more optical devices 14, which may for example be electronic video cameras, preferably located within a tunnel, which is not shown in the accompanying figures and is of a known type.

In this context, therefore, the rolling of the products A allows the video cameras to observe the entire surface of the products A.

In addition to the unit 1, a method 100 for conveying products A, performed indeed by means of the unit 1 described so far, is also a subject matter of the protection claimed herein.

The method 100 provides at least, in a step a., for depositing each product A in a respective seat 3.

Then, in a step b., the method 100 provides for conveying each product A while it is arranged (in the manners already described) in the respective seat 3.

During the step b., the method 100 provides, in a step c., for imparting the rotation to the first elements 2a that transit along the first useful part Di of the path B. Moreover, and still during step b., the method 100 provides, in a step d., for imparting the rotation to the second elements 2b that transit along the second useful part D₂ of the path B.

The operation of the unit according to the invention has in practice already been described.

As they move downstream, the products A are arranged one by one in adequately spaced seats 3, each resting on a first element 2a and on the second element 2b located downstream.

In this context, it has been found that the choice to provide the unit 1 with elements 2a, 2b having different shapes and with means 4 that actuate the rotation of the first elements 2a and of the second elements 2b at their transit on useful parts D D₂ that overlap only partially, ensures the simultaneity at least of the activation or closure of the step of rotation of the two elements 2a, 2b that support each product A in a seat 3. Preferably, the simultaneity of the entire rotation step is ensured.

Simultaneity, in particular of the closing step, ensures control of the position of the products A at the end of their rolling, a control that is further reinforced in the preferred embodiment, which provides for simultaneity of the entire rotation step.

In the preferred embodiment, such rotation is in particular achieved by virtue of the useful segments 6a, 6b (arranged mutually side by side and offset below the path B) of the transmission elements 5a, 5b that engage the elements 2a, 2b (the major disks 12 A, for example).

In any case, the partial overlap of the useful portions D D₂ (in turn made possible by the different shape assumed by the elements 2a, 2b) causes the rotation step to starts and/or end simultaneously, thereby ensuring that the (rotational) stress to which each product A is subjected by both elements 2a, 2b that support it also starts and/or ends simultaneously, and this ensures control of the products A during the entire step of their rolling, and in particular at the end of the latter. In known embodiments, where it is impossible to ensure simultaneity, the rotation of only one of the rollers or in any case of the supporting elements adopted in fact generates an irregularity and especially an unpredictability in the rolling of the products A that is obviously unwelcome (and therefore the invention is not afflicted by such drawbacks).

In the (preferred but not exclusive) application that provides for the presence of the vision system 13, whose information acquisition function is optimized by ensuring the rolling of the products A, the simultaneity of the rotation step (or at least of its closure) allows, for example, to know its final position, assumed at the end of rolling. This allows further downstream commands to be given more safely and reliably.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of appended claims; all the details may furthermore be replaced with other technically equivalent ones.

In the embodiments shown, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other embodiments.

In practice, the materials used, as well as the dimensions, may be any according to the requirements and the state of the art.

The disclosures in Italian Patent Application No. 102024000002280 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A conveyance unit for horticultural products (A), comprising at least:

- an alternating succession of first supporting elements (2a) and second supporting elements (2b), cyclically movable along a predefined path (B), each pair composed of said first element (2a) and said following second element (2b), forming an accommodation and conveyance seat (3) for a respective horticultural product (A),

- rotation means (4) configured to impart to each of said elements (2a, 2b), during its advancement along said path (B), a rotation about a respective main axis (C), which is substantially transverse to said path (B), characterized in that said first elements (2a) have a different shape with respect to said second elements (2b) and said rotation means (4) are configured at least to impart the rotation to said first elements (2a) transiting along a first useful part (Di) of said path (B) and at least to impart the rotation to said second elements (2b) transiting along a second useful part (D₂) of said path (B), said useful parts (D D₂) being partially mutually superimposed at a common portion (D₃), at least one of said useful parts (D D₂) extending along said path (B) beyond said common portion (D₃), for the rotation of a further said respective element (2a, 2b).

2. The unit according to claim 1, characterized in that said first useful part (Di) extends upstream beyond said common portion (D₃) for the rotation of a further said first element (2a), said second useful part (D₂) extending downstream beyond said common portion (D₃) for the rotation of a further said second element (2b).

3. The unit according to claim 1 or 2, characterized in that said means (4) comprise at least one first transmission element (5a) and one second transmission element (5b), which are arranged substantially side by side along respective closed imaginary curves and are configured for engagement with corresponding said elements (2a, 2b) transiting along said first useful part (Di) and along said second useful part (D₂), respectively.

4. The unit according to claim 3, characterized in that each of said transmission elements (5a, 5b) comprises a respective useful segment (6a, 6b) which faces the corresponding said useful part (D D₂) of said path (B) and is configured for engagement with corresponding said elements (2a, 2b), said segments (6a, 6b) being at least partially offset with respect to the advancement direction of said elements (2a, 2b) along said path (B).

5. The unit according to claim 3 or 4, characterized in that said means (4) comprise a system (8) for moving said transmission elements (5a, 5b) along the respective said imaginary curves.

6. The unit according to claim 5, characterized in that said movement system (8) comprises a motor (9) provided with an output shaft (10), said transmission elements (5a, 5b) being wound around respective main pulleys (I la, 11b) keyed to said output shaft (10).

7. The unit according to one or more of the preceding claims, characterized in that each of said elements (2a, 2b) comprises at least two primary disks (12A, 12B) having different diameters, which rotate in a mutually integral manner and are coaxially aligned along the respective said main axis (C), a major primary disk (12A) of said primary disks having a larger diameter than a minor primary disk (12B) of said primary disks, said major primary disks (12A) and said minor primary disks (12B) being mutually offset in said two elements (2a, 2b) of said seat (3).

8. The unit according to claim 7, characterized in that said transmission elements (5a, 5b) engage said respective elements (2a, 2b) at said major disks (12A).

9. The unit according to one or more of the preceding claims, characterized in that it comprises a vision system (13) configured at least for acquiring information related to each product (A) upon its transit at least over said common portion (D₃) of said useful parts (D D₂).

10. A method for conveying horticultural products (A), executed by means of a unit (1) according to one or more of the preceding claims, which provides at least for the following steps of: a. depositing each product (A) in a respective seat (3), b. conveying each product (A) accommodated in the respective seat (3), c. during said step b., imparting rotation to the first elements (2a) transiting along the first useful part (Di) of the path (B) d. during said step b., imparting rotation to the second elements (2b) transiting along the second useful part (D₂) of the path (B).