WO2022023996A1

WO2022023996A1 - Machine for cleaning shores

Info

Publication number: WO2022023996A1
Application number: PCT/IB2021/056858
Authority: WO
Inventors: Ezio Esposito
Original assignee: Ecocentro Sardegna S.R.L.
Priority date: 2020-07-29
Filing date: 2021-07-28
Publication date: 2022-02-03

Abstract

The machine (10) comprises: a self-propelled wagon (12) with a frame structure (14) provided with wheels (18, 20) and with a driver's cabin (16) carried by the frame structure (14); a pick-up unit (22) arranged at the front end of the machine (10) and comprising a raking device (32) for picking up wastes from the shore; a collecting unit (24) mounted on the frame structure (14) and configured to collect the wastes picked up by the pick- up unit (22); and a conveying unit (26) interposed between the pick-up unit (22) and the collecting unit (24) and comprising conveying means (80) for conveying towards the collecting unit (24) the wastes picked up by the pick-up unit (22). The raking device (32) comprises a rotary drum (60) provided with a plurality of needles (62) protruding from an outer cylindrical surface of the drum (60). The conveying unit (26) further comprises an arm (28), which is hinged at the rear end thereof to the frame structure (14) for rotation about a transverse axis of rotation (xi) and carries said conveying means (80), and actuating means (74) operatively interposed between the frame structure (14) and the arm (28) for driving the latter into rotation about its axis of rotation (xi). The pick-up unit (22) is connected to the front end of the arm (28), in front of the driver's cabin (16), in such a manner that the pick-up unit (22) is movable between a lowered working position and a raised rest position as a result of the rotation of the arm (28) under control of said actuating means (74).

Description

MACHINE FOR CLEANING SHORES

Technical field of the invention

The present invention relates to a machine for cleaning shores, i.e. a machine able to pick up wastes from the shore and treat such wastes.

State of the art

The wastes resulting from the cleaning of the shores are typically formed mainly by an organic fraction (algae and aquatic plants, in particular Posidonia) and by a mineral fraction (sand and shells).

The phenomenon of the wastes (in particular of the Posidonia) on the shores is becoming more and more critical, in particular in Italy, where about 3.270 km of the about 7.500 km of natural coasts are shallow, sandy and graveled coasts. This phenomenon is destined to get worse due to the increase in the sea temperature and, more generally, due to the ongoing climate changes, which are leading to an uncontrolled growth of the marine flora.

The problem is spread over the whole territory of Italy and concerns in particular the following two aspects:

- the destination of the wastes (in particular of the Posidonia) deriving from the cleaning of the shores, and

- the preservation of the shores and the protection against coastal erosion.

The wastes resulting from the cleaning of the shores contain huge amounts of sand and the ways currently used to remove such wastes do not allow to separate in situ the sand from the wastes. The consequence is that each year tons of precious sand are lost during the operations of handling of the beached wastes (namely, when the wastes are removed from the shore to be disposed of or collected in banks and/or buried in areas behind the shore) or return back in the sea together with the beached wastes during coastal storms, when in autumn the wastes previously picked up and accumulated are moved back to the water edge.

The problem of the management of the beached wastes has been so far dealt with in a superficial manner and, most of all, in a non-decisive manner.

Typically the wastes are removed from the shore, usually just before the tourist season, by means of earth-moving machines such as wheeled excavator-loaders, bulldozers, etc. The wastes removed from the shore are then accumulated in regions behind the shore or in provisional storage areas, with the formation of build-ups or, in some cases, with partial burying, and finally brought back to the original shore at the end of the tourist season, hoping that the wastes will return back into the sea by virtue of the autumn and winter coastal storms.

Such a way of management of the beached wastes is clearly affected by a number of problems, in particular:

- the loss of huge amounts of sand and the resulting phenomenon of coastal erosion;

- the damages to the water edge due to the repeated use of non-suitable means, both to remove the wastes from the shore before the tourist season and to reposition the wastes on the shore in autumn; and

- the provisional accumulation of the wastes in non-suitable areas, typically build-ups and/or burials in regions behind the shores.

Summary of the invention

It is an object of the present invention to provide a machine for cleaning shores which allows to overcome at least one of the aforementioned problems of the prior art.

This and other objects are achieved by virtue of a machine for cleaning shores having the features specified in independent claim 1.

Preferred embodiments of the machine according to the present invention form the subject-matter of the dependent claims.

In short, the invention is based on the idea of providing a machine comprising:

- a self-propelled wagon with a frame structure provided with wheels and with a driver's cabin carried by the frame structure;

- a pick-up unit arranged at the front end of the machine and comprising pick-up means for picking up wastes from the shore;

- a collecting unit mounted on the frame structure and configured to collect the wastes picked up by the pick-up unit; and

- a conveying unit interposed between the pick-up unit and the collecting unit and comprising conveying means for conveying towards the collecting unit the wastes picked up by the pick-up unit; wherein said pick-up means comprise a raking device having a rotary drum provided with a plurality of needles protruding from an outer cylindrical surface of the drum; wherein the conveying unit further comprises an arm, which is hinged at a rear end thereof to the frame structure for rotation about a transverse axis of rotation and carries said conveying means, and actuating means, in particular one or more linear actuation devices, such as for example pneumatic or hydraulic cylinders, operatively interposed between the frame structure and the arm to drive the latter into rotation about said transverse axis of rotation; and wherein the pick-up unit is connected to the front end of the arm, in front of the driver's cabin, in such a manner that the pick-up unit is movable between a lowered working position and a raised rest position as a result of the rotation of the arm under control of said actuating means.

By virtue of a such a configuration, the machine is able not only to pick-up wastes from the shore, but also to collect them in the collecting unit on board of the machine. Moreover, the use, as means for picking up wastes from the shore, of a raking device configured in this manner facilitates the separation of the sand from the wastes during the pick-up operation and the fall of the sand thus separated directly on the shore.

Preferably, the raking device further comprises a cylindrical casing which extends in a transverse direction and inside which the rotary drum is received. The cylindrical casing has a plurality of annular slits through which the needles of the drum protrude, in such a manner as to allow the needles, as a result of the rotary movement of the drum, to sink in the sand of the shore and pick up the wastes from the shore.

The needles of the rotary drum are advantageously formed by metal wire, in particular steel wire, having for example a circular or rectangular cross-section, so as to be somewhat flexible in a plane perpendicular to the axis of rotation of the drum and be thus able to adapt themselves to possible obstacles present in the sand.

Preferably, the pick-up unit further comprises belt transport means interposed between the pick-up means and the conveying unit to transport the wastes picked up by the pick up means towards the conveying unit. Said belt transport means advantageously comprise a perforated belt having a plurality of through holes through which the sand possibly picked up by the pick-up means together with the wastes can fall back on the shore. Vibrating means may be associated to the perforated belt for exerting a vibrating or shaking action onto the belt to facilitate separation of the sand from the wastes during transport on the belt from the pick-up means to the conveying unit.

According to an embodiment, the pick-up unit comprises a support frame on which the pick-up means and, if present, the belt transport means are mounted. The support frame is preferably connected to the front end of the conveying unit by means of a connection mechanism configured as an articulated parallelogram mechanism.

The support frame preferably comprises a first frame part, directly connected to the arm by means of the connection mechanism, and a second frame part which carries the pick up means and, if present, the belt transport means and is hinged to the first frame part about a respective transverse axis of rotation. The first frame part is provided with idle wheels which during operation of the machine can roll on the surface of the shore. In this case actuating means are provided between the first frame part and the second frame part and comprise for example a pair of linear actuation devices, such as a pair of pneumatic or hydraulic cylinders, to adjust the angular position of the second frame part relative to the first frame part about the aforementioned transverse axis of rotation, and thus adjust the height of the pick-up means from the ground.

The pick-up unit is conveniently detachably connected to the arm of the conveying unit, so that it can be detached from the machine in case of need.

Preferably, the conveying unit further comprises, at the front end of the arm, a rotary drum, which is rotatably mounted about a transverse axis of rotation, and a casing, which surrounds at least partially the rotary drum and with which the rotary drum cooperates to transfer to the conveying means the wastes coming from the pick-up unit. The casing advantageously comprises a rear portion, which is arranged below the rotary drum and has a substantially flat configuration, and a front portion, which extends at least partially in front of the rotary drum and has an arc-shaped configuration so as to act as a feeding hopper in which the material coming from the pick-up unit is discharged to be then transferred through the rotary drum to the conveying means. The front portion of the casing may be advantageously detached from the rear portion, in particular when the pick-up unit is not used, in which case the lower portion of the casing will act as a conveyor blade for picking up the wastes from the shore and transfer them, in cooperation with the rotary drum, towards the conveying means.

The rotary drum of the conveying unit may have different configurations and is detachably mounted on the arm to allow, if necessary, to replace the drum with another drum having the desired configuration. For example, the drum may be configured to operate as a pick-up drum, in case the machine operates without pick-up unit, and hence to pick up directly the wastes from the shore without the use of the pick-up means of the pick-up unit. In this case, a spiral-shaped profile will be provided on the outer surface of the drum for conveying the wastes, as a result of the rotation of the drum, towards the central part of the same drum. On the other hand, in case the machine operates with the pick-up unit mounted at the front end of the arm, on the conveying unit there will be preferably mounted a rotary drum having on the outer surface thereof cutting elements, such as for example knives, preferably arranged along a spiral-shaped path, for exerting a breaking-up and shredding action on the wastes, before the latter are conveyed towards the collecting unit. The rotary drum may alternatively be provided with crushing elements connected to the drum by means of a joint, in which case the drum is particularly suitable for crushing large-sized wastes.

Further features and advantages of the present invention will be evident from the following detailed description, given purely by way of non-limiting example.

Brief description of the drawings

In the following detailed description of the invention reference will be made to the Figures of the attached drawings, wherein:

- Figure 1 is a side view of a machine for cleaning shores according to an embodiment of the present invention, with the pick-up unit in its working position;

- Figure 2 is a view similar to that of Figure 1 , wherein the pick-up unit of the machine is in its rest position, raised from the ground;

- Figure 3 is a side view which shows in detail the pick-up unit of the machine of Figure

1 ;

- Figure 4 is a side view of the pick-up unit and of the conveying unit of the machine of Figure 1 ;

- Figure 5 is a front view of the needle raking device of the pick-up unit of Figure 4;

- Figure 6 is a side view which schematically shows the arrangement of the needles of the rotary drum of the needle raking device of Figure 5;

- Figure 7 is a side view of the rotary drum of the conveying unit of Figure 3;

- Figures 8 and 9 are side views which show the front portion of the conveying unit of Figure 4, in two respective operating configurations of the machine; and

- Figures 10 and 11 are side views which show the machine of Figure 1 in an operating configuration without pick-up unit, in the working position and in the rest position, respectively.

Detailed description

With reference first to Figures 1 and 2, a machine for cleaning shores (hereinafter simply referred to as "machine") according to an embodiment of the present invention is generally indicated 10.

The machine 10 comprises a self-propelled wagon 12 with a frame structure 14 and with a driver's cabin 16 carried by the frame structure 14, in particular in the front part of the latter. The frame structure 14 is provided with wheels, in particular a pair of front wheels 18 and a pair of rear wheels 20. Preferably, both the front wheels 18 and the rear wheels 20 are configured as driving and steering wheels. Moreover, both the front wheels 18 and the rear wheels 20 have a large diameter and an increased width, so as to provide a wide contact surface and, therefore, minimize the contact pressure on the sand, thereby ensuring the required payload and traction but at the same time avoiding the formation of furrows and depressions in the shore. Moreover, in order to preserve as much as possible the integrity of the shore, both the front wheels 18 and the rear wheels 20 are provided with tyres having a special tread design for minimizing tracks and furrows in the sand. At the same time, the load distribution of the machine (for example the arrangement of the engine in the front part of the machine) is designed so as to be as balanced as possible on the two axles, thereby further minimizing the impact of the machine on the shore.

As will be better explained further on, during operation the machine enters the shore to be cleaned and typically operates by moving longitudinally back and forth on the shore until it covers the entire surface of the shore, thereby minimizing the number of steering manoeuvres, which are typically the kind of manoeuvres which most damages the shore. The machine is able to remove both the wastes resting on the surface of the shore, by means of a raking action, and the wastes collected in build-ups (for example aquatic plants beached due to costal storms, wastes/debris accumulated by human beings, etc.) or laid down on the foreshore or, again, partially floating in the first part of the sea.

The machine 10 further comprises a pick-up unit 22 for picking up wastes from the shore, a collecting unit 24 for collecting the wastes picked up by the pick-up unit 22, and a conveying unit 26 interposed between the pick-up unit 22 and the collecting unit 24 for conveying towards the collecting unit 24 the wastes picked up by the pick-up unit 22. The collecting unit 24 is mounted on the frame structure 14, on the rear of the driver's cabin 16. The conveying unit 26 comprises an arm 28, hinged at its rear end to the frame structure 14 so as to be rotatable about a transverse axis of rotation xi (i.e. a horizontal axis of rotation oriented perpendicular to the direction of travel, or fore-and-aft direction, of the machine). The pick-up unit 22 is connected to the front end of the conveying unit 26, in front of the driver's cabin 16, so as to be movable between a lowered working position (Figure 1) and a raised rest position (Figure 2) as a result of the rotation of the arm 28 about the axis of rotation xi .

With reference in particular to Figure 3, the pick-up unit 22 comprises a support frame 30 on which there are mounted a needle raking device 32 (hereinafter simply referred to as "raking device 32") for picking-up the wastes from the shore and a transport device 34 arranged downstream of the raking device 32 (i.e. on the rear of the raking device 32) for transporting towards the conveying unit 26 the wastes picked up by the raking device 32. In an alternative embodiment of the machine (not shown), the pick-up unit 22 does not have any transport device, in which case the wastes picked up by the raking device 32 are transferred by gravity directly to the conveying unit 26.

The support frame 30 is connected to the front end of the conveying unit 26 by means of a connection mechanism 36, which is advantageously configured as an articulated parallelogram mechanism comprising, for each side of the support frame, a pair of connecting arms 38 and 40, that is to say, an upper connecting arm and a lower connecting arm, respectively, which are oriented parallel to each other and are each hinged at its front end, by means of respective joints 42 and 44, to the support frame 30 and at its rear end, by means of respective joints 46 and 48, to a part (schematically shown in dashed line in Figure 3) of the conveying unit 26. By virtue of such a connection mechanism, during operation the orientation of the pick-up unit 22 with respect to the direction of travel of the machine 10 remains unchanged even in case of vertical movements of the pick-up unit 22 due to possible depressions and elevations of the shore, and therefore the amount of sinking of the needles of the raking device 32 in the sand of the shore remains constant. The joints 42, 44, 46 and 48 of the connecting arms 38 and 40 are advantageously made as ball joints, so as to allow the support frame 30 to tilt transversely with respect to the machine 10, i.e. in a plane perpendicular to the fore-and-aft direction of the machine.

The support frame 30 comprises a first frame part 50, or rear part, arranged on the same side as the conveying unit 26, to which the front ends of the connecting arms 38 and 40 of the connection mechanism 36 are hinged. The first frame part 50 is mounted on a pair of idle wheels 52 (only one of which can be seen in the side view of Figure 3) which during operation of the machine roll on the surface of the shore as a result of the forward movement of the self-propelled wagon 12. The support frame 30 further comprises a second frame part 54, or front part, which carries the raking device 32 and the transport device 34. The second frame part 54 is hinged by means of a cylindrical pin 56 to the first frame part 50 so as to be rotatable relative to the latter about a transverse axis of rotation X2. More specifically, the second frame part 54 comprises a lower structure 54a, which extends substantially horizontally, and an upper structure 54b, which extends in a direction substantially perpendicular, or slightly inclined to the perpendicular, to the lower structure 54a starting from a rear region of the latter. The raking device 32 is mounted at the front end of the lower structure 54a of the second frame part 54. The cylindrical pin 56 connects the lower end of the first frame part 50 with the rear end of the lower structure 54a of the second frame part 54.

Between the first frame part 50 and the second frame part 54, in particular between the first frame part 50 and the upper structure 54b of the second frame part 54, above the pin 56, a linear actuation device 58, such as for example a pneumatic or hydraulic cylinder, is provided, which device allows to adjust the angular position of the second frame part 54 relative to the first frame part 50 about the axis of rotation X₂, thereby changing the height of the raking device 32 from the ground, and hence the amount of sinking of the needles of the raking device 32 in the sand of the shore. The linear actuation device 58 is controllable by the operator by means of a suitable control member (not shown) placed inside the driver's cabin 16.

According to another embodiment (not shown), a pair of idle wheels (one for each side) may be mounted at the front end of the lower structure 54a of the second frame part 54, the position of these wheels relative to this frame part being adjustable vertically by means of crank-type manual actuation systems, so as to provide a further possibility for adjusting the height of the front end of the pick-up unit from the ground, that is to say, for adjusting the depth at which the needles of the raking device sink in the sand, in particular in case of an irregular shore profile.

As already stated, the raking device 32 has the function of picking up wastes, such as algae, aquatic plants (in particular the Posidonia), anthropic wastes and/or debris of other nature from the shore, and, simultaneously with the pick-up operation, of carrying out by means of a raking and forwarding action a first separation of these wastes from the sand, causing the sand to fall on the shore.

With reference also to Figures 5 and 6, the raking device 32 basically comprises a rotary drum 60 (hereinafter simply referred to as "drum 60") provided with a plurality of needles 62, a cylindrical casing 64 (hereinafter simply referred to as "casing 64") which extends in a transverse direction and inside which the drum 60 is rotatably mounted about a transverse axis of rotation X₃, and motor means (not shown, but of per-se-known type) for driving the drum 60 into rotation about the axis of rotation X₃. These motor means are for example formed by a hydraulic motor supplied by the main hydraulic circuit of the machine and controllable from the driver's cabin 16. The drum 60 is made as a cylindrical, preferably hollow, body whose radius is indicated r-r. The needles 62 of the drum 60 are arranged in several longitudinal rows, which are angularly equally spaced apart from each other. In the embodiment proposed herein, as shown in Figures 3 and 6, the needles 62 are arranged in six rows, but of course the number of needle rows might be different. The needles 62 of each row are longitudinally spaced from each other by a given pitch p, which is preferably constant throughout the longitudinal extension of the drum 60. The needles 62 are mounted with their proximal ends in respective seats 66 provided on the outer cylindrical surface of the drum 60 and extend in the radial direction, or somewhat inclined to the radial direction, protruding outwardly of the casing 64 through annular slits 68 provided in the same casing, so as to sink in the sand of the shore and be thus able to pick up possible wastes from the shore. The needles 62 are advantageously formed by metal wire, in particular steel wire, having for example a circular or rectangular cross-section, so as to be somewhat flexible in a plane perpendicular to the axis of rotation X₃ of the drum 60 and be thus able to adapt themselves to possible obstacles present in the sand, such as for example rocks of such a mass that they cannot be lifted by the raking device 32.

The casing 64 comprises a front casing portion 64a whose cross-section has an outline in the shape of a substantially circular arc extending for a certain angle, for example approximately equal to 180°, with its centre on the axis of rotation X₃ of the drum 60 and with a radius rc larger than the radius Gt of the drum 60, but smaller than the sum of the radius Gt of the drum 60 and of the length L of the needles 62, in such a manner that the needles 62 which are at the front casing portion 64a protrude from the latter by a certain length s. The casing 64 further comprises a substantially flat, upper casing portion 64b, which is joined to the front casing portion 64a at an upper end of the latter and extends rearwards with a slight downward inclination, as well as a rear casing portion 64c, which is placed at a distance from the axis of rotation X₃ of the drum 60 larger than the sum Gt + L, in such a manner that the needles 62 which are at the rear casing portion 64c do not protrude from the latter, but remain contained within the same.

During operation, therefore, as a result of the rotation of the drum 60 about the axis of rotation X₃ (rotation which takes place in counter-clockwise direction, as shown by arrow, with respect to a person looking at Figure 6), the needles 62 begin to protrude from the casing 64 at the bottom of the rear casing portion 64c, so as to sink in the sand of the shore, then continue to protrude from the casing 64 by the aforementioned length s along the whole front casing portion 64a, so as to carry with them the wastes picked up from the shore and finally return gradually into the casing 64 at the upper casing portion 64b, thereby releasing on that casing portion the wastes carried with them until then. As a result of the forward movement of the raking device 32 along with the machine 10, as well as of the rotation of the drum 60 with a certain angular speed (which the operator in the driver's cabin can advantageously adjust by suitably controlling the aforementioned motor means) about the axis of rotation X₃, a shore area with a width substantially equal to the width of the drum 60 is raked and therefore possible wastes present on the shore (such as for example algae, aquatic plants, anthropic wastes, etc.) are picked up, which wastes are lifted by the needles 62 and urged rearwards to the subsequent sections of the machine. The sand, just due to this raking action, mostly remains on the shore or, if picked up along with the wastes, is separated from the latter and falls back on the shore. In fact, while the wastes are picked up by the needles 62, the sand falls back on the shore either directly or through the slits 68 provided in the casing 64. Most of the sand is thus already separated from the wastes in the initial phase of picking up of the latter.

In Figure 6, the height of the axis of rotation x₃ of the drum from the ground is indicated H and the amount of sinking of the needles 62 in the sand of the shore depends on this height. As previously mentioned, the height H may be varied by the operator by suitably controlling the linear actuation device 58 interposed between the first frame part 50 and the second frame part 54 of the support frame 30.

With reference now again to Figure 3, the transport device 34 comprises first of all a transport belt 70 (hereinafter simply referred to as "belt 70") wound about a series of deflection rollers 72, one of which operates as driving roller. The transport belt 70 may be advantageously provided with projections which help the transport of the material, preventing it from slipping back downwards. The deflection rollers 72 are supported by the second frame part 54 of the support frame 30 and are arranged in such a manner that the active branch (indicated 70a) of the belt 70, i.e. the branch through which the wastes are transported towards the conveying unit 26, is inclined upwards by a certain angle a. The belt 70 may be made as a perforated belt, i.e. as a belt having a plurality of through holes (not shown) through which the sand that is possibly picked up by the raking device 32 along with the wastes can fall back on the shore. Vibrating means (not shown, but of per-se-known type) may be associated to the belt 70 for exerting a vibrating or shaking action onto the belt to facilitate separation of the sand from the wastes during the transport towards the conveying unit 26.

The conveying unit 26 comprises, in addition to the aforementioned arm 28, an actuation device 74, in particular a linear actuation device, such as for example a pneumatic or hydraulic cylinder, interposed between the arm 28 and the frame structure 14 to adjust the angular position of the arm 28 relative to the frame structure 14 about the axis of rotation xi. The actuation device 74 is also controllable by the operator through a suitable control member (not shown) placed inside the driver's cabin 16.

The conveying unit 26 further comprises a rotary drum 76 (hereinafter simply referred to as "drum 76") and a cylindrical casing 78 (hereinafter simply referred to as "casing 78") mounted at the distal end (front end) of the arm 28 and a transport belt 80 (hereinafter simply referred to as "belt 80") which extends along the tilting arm 28 between the drum 76 and the proximal end (rear end) of the arm 28.

With reference in particular to Figures 7 to 9, the drum 76 is rotatably mounted on the arm 28 for rotation about a transverse axis of rotation x*. Motor means (not shown, but of per-se-known type) are associated to the drum 76 for driving the drum into rotation about the axis of rotation X₄. These motor means are controllable by the operator by means of a suitable control member (not shown) placed in the driver's cabin 16, preferably with the possibility to adjust the rotational speed of the drum or to change the direction of rotation of the drum, for example to disengage the drum in case of obstructions, formation of blocks of material or clogs.

The casing 78 surrounds at least partially the drum 76 and comprises a rear portion 78a, which is arranged underneath the drum 76 and preferably has a substantially flat configuration, and a front portion 78b, which extends at least partially in front of the drum 76 and has an arc-shaped configuration so as to act as a feeding hopper in which the material coming from the pick-up unit 22 is discharged. The front portion 78b of the casing 78 may advantageously be detached from the rear portion 78a, when - as explained further on - the machine 10 operates without pick-up unit 22.

The drum 76 is provided with a plurality of protruding elements 82, which protrude radially from the outer cylindrical surface of the drum and may have various configurations depending on the function the drum is intended to perform,.

In the configuration of the machine 10 shown in Figures 1 , 2 and 4, in which the machine is provided with the pick-up unit 22 for picking up wastes from the shore, the drum 76 has the function of homogenising the size of the picked-up material to be collected in the collecting unit 24, so as to make it more suitable for the subsequent treatment of the same (for example a washing treatment at a stationary washing apparatus), as well as - preferably - also the function of conveying the material falling in the casing 78 from the transport device 34 of the pick-up unit 22 towards the centre of the same drum, thereby ensuring that the material is correctly fed to the belt 80. In this case, the protruding elements 82 of the drum 76 are configured as cutting elements, such as for example knives, to exert a breaking-up and shredding action on the picked-up material, which is particularly useful in case the picked-up material contains fractions extending in length (for example branches, aquatic plants with elongated leaves, etc.). Preferably, the protruding elements 82 are arranged along a spiral-shaped path on the cylindrical surface of the drum 76, so as to perform also the aforementioned function of conveying the material towards the centre of the drum.

In case the material to be picked up from the shore includes large-sized fractions which cannot be shredded by means of knife-type cutting elements, but require a grinding action, then the protruding elements of the drum will be made as jointed elements, so that the drum can operate as a sort of hammer mill.

As shown in Figures 9 to 11 , in case the pick-up unit 22 is not mounted on the machine 10, the drum 76 will be configured as a pick-up drum for picking up the wastes directly from the shore. In this case, on the outer surface of the drum 76 a spiral-shaped profile will be provided for conveying the wastes towards the centre of the same drum. During operation, the arm 28 of the conveying unit 26 is lowered from a rest position (Figure 11), in which the drum 76 is raised from the ground, to a working position (Figure 10), in which the drum 76 rests on the wastes to be picked up, sinking partially therein. The rotation of the drum 76, as well as the forward movement of the rear portion 78a of the casing 78 (acting in this case as a conveyor blade) along with the machine 10, cause the wastes to be picked up and, at the same time, to be conveyed towards the centre of the drum 76, thereby making the transfer of the wastes to the belt 80 easier. Moreover, the forced passage in the space provided between the drum 76 and the rear portion 78a of the casing 78 produces a homogenization of the size of the material, which - as already stated - makes the subsequent treatment of the same material easier.

The drum 76 is detachably mounted on the arm 28, so as to allow each time the use of a specific drum depending on the type of pick-up operation the machine is required to carry out.

As far as the belt 80 is concerned, it has the function of transporting the material from the drum 76 to the collecting unit 24. The belt 80 may be made as a perforated belt, so as to allow the sand possibly transported together with the material picked up from the shore to be separated and fall on the shore. The belt 80 is wound about deflection rollers 84 (one of which is motor-driven and is controllable at a variable speed so as to allow the operator in the driver's cabin to adjust the linear speed of the belt 80, for example depending on the type and the amount of material picked up from the shore or depending on the desired trajectory of "launch" of the material into the collecting unit 24), which are rotatably supported on the arm 28 and are arranged in such a manner that the active branch (indicated 80a) of the belt 80 extends substantially parallel to the arm 28.

Finally, the collecting unit 24 is formed by a casing having a maximum volume in the order for example of 20-25 m³, so as to provide the machine 10 with a proper working autonomy. Once the collecting unit 24 is completely full of wastes, the wastes are transferred to a suitable means of transport to be transported to an authorized recycling/disposal centre, and the machine 10 can return back to work to remove wastes from the shore.

As it is evident from the above description, a machine for cleaning shores according to the present invention allows to achieve at least the following advantages over the prior art.

By virtue of the particular configuration of the pick-up unit, the machine is able to carry out a preliminary separation of the wastes from the sand, thereby minimizing the amount of sand removed from the shore.

Moreover, the machine is able to pick up wastes from the shore even when the wastes are present in very high build-ups or layers.

The machine allows to avoid, or at least reduce, the damages caused by the machines currently used for shore cleaning operations.

The machine ensures a proper working autonomy, which allows to minimize the required movements of the machine.

The present invention has been described herein with reference to a preferred embodiment thereof. It is intended that other embodiments may be envisaged, which share with the one described herein the same inventive core, as defined by the scope of the enclosed claims.

Legend of the reference numerals

10) machine

12) self-propelled wagon

14) frame structure of the self-propelled wagon

16) driver's cabin

18) front wheels of the self-propelled wagon

20) rear wheels of the self-propelled wagon

22) pick-up unit

24) collecting unit

26) conveying unit

28) arm of the conveying unit

30) support frame of the pick-up unit

32) needle raking device

34) transport device

36) connection mechanism between pick-up unit and conveying unit

38) upper connecting arm

40) lower connecting arm

42) front joint of the upper connecting arm

44) front joint of the lower connecting arm

46) rear joint of the upper connecting arm

48) rear joint of the lower connecting arm

50) first part of the support frame

52) idle wheels of the pick-up unit

54) second part of the support frame

56) cylindrical pin

58) linear actuation device

60) rotary drum

62) needles

64) cylindrical casing of the raking device 64a) front portion of the cylindrical casing 64b) upper portion of the cylindrical casing 64c) rear portion of the cylindrical casing 66) seats for the needles 68) annular slits 70) transport belt of the pick-up unit

70a) active branch of the transport belt 72) deflection rollers of the transport belt 74) actuation device 76) rotary drum of the conveying unit 78) cylindrical casing of the conveying unit

80) transport belt of the conveying unit 82) protruding elements 84) deflection rollers

Claims

1. Machine (10) for cleaning shores, comprising:

- a self-propelled wagon (12) with a frame structure (14) provided with wheels (18, 20) and with a driver's cabin (16) carried by the frame structure (14);

- a pick-up unit (22) arranged at the front end of the machine (10) and comprising pick up means (32) for picking up wastes from the shore;

- a collecting unit (24) mounted on the frame structure (14) and configured to collect the wastes picked up by the pick-up unit (22); and

- a conveying unit (26) interposed between the pick-up unit (22) and the collecting unit (24) and comprising conveying means (80) for conveying towards the collecting unit (24) the wastes picked up by the pick-up unit (22); wherein said pick-up means (32) comprise a raking device (32) having a first rotary drum (60) provided with a plurality of needles (62) protruding from an outer cylindrical surface of said first drum (60); wherein the conveying unit (26) further comprises an arm (28), which is hinged at a rear end thereof to the frame structure (14) for rotation about a first transverse axis of rotation (xi) and carries said conveying means (80), and first actuating means (74) operatively interposed between the frame structure (14) and the arm (28) to drive the latter into rotation about said first axis of rotation (xi); and wherein the pick-up unit (22) is connected to the front end of the arm (28), in front of the driver's cabin (16), in such a manner that the pick-up unit (22) is movable between a lowered working position and a raised rest position as a result of the rotation of the arm (28) under control of said first actuating means (74).

2. Machine according to claim 1 , wherein the raking device (32) further comprises a first casing (64) which extends in a transverse direction and inside which said first drum (60) is received, said first casing (64) having a plurality of slits (68) through which the needles (62) of said first drum (60) protrude, in such a manner as to allow the needles (62), as a result of the rotary movement of said first drum (60), to sink in the sand of the shore and pick up the wastes from the shore.

3. Machine according to claim 1 or claim 2, wherein the needles (62) of said first drum (60) are formed by metal wire, in particular steel wire.

4. Machine according to any one of the preceding claims, wherein the pick-up unit (22) further comprises belt transport means (34) interposed between said pick-up means (32) and the conveying unit (26) for transporting towards the conveying unit (26) the wastes picked up by said pick-up means (32).

5. Machine according to claim 4, wherein said belt transport means (34) comprise a belt (70), in particular a perforated belt.

6. Machine according to claim 5, wherein said belt transport means (34) further comprise vibrating means associated to said belt (70) to exert on the latter a vibrating or shaking action to facilitate separation of the sand from the wastes during transport of the wastes on said belt (70) from said pick-up means (32) to the conveying unit (26).

7. Machine according to any one of the preceding claims, wherein the pick-up unit (22) comprises a support frame (30), on which said pick-up means (34) are mounted, and a connection mechanism (36), through which the support frame (30) is connected to the front end of the conveying unit (26).

8. Machine according to claim 7, wherein said connection mechanism (36) is configured as an articulated parallelogram mechanism.

9. Machine according to claim 7 or claim 8, wherein the support frame (30) comprises a first frame part (50), which is arranged on the same side as the conveying unit (26) and is provided with idle wheels (52) which during operation of the machine are allowed to roll on the surface of the shore, a second frame part (54), which carries said pick-up means (32) and is hinged to the first frame part (50) about a second transverse axis of rotation (X2), and second actuating means (58), comprising in particular a linear actuation device, for adjusting the angular position of the second frame part (54) relative to the first frame part (50) about said second axis of rotation (X2).

10. Machine according to any one of the preceding claims, wherein the conveying unit (26) further comprises, at the front end of the arm (28), a second rotary drum (76), rotatably mounted about a third transverse axis of rotation (X4), and a second casing (78), which surrounds at least partially said second drum (76) and with which said second drum (76) cooperates to transfer to said conveying means (80) the wastes coming from the pick-up unit (22).

11. Machine according to claim 10, wherein said second casing (78) comprises a front casing portion (78b), extends at least partially in front of said second drum (76) and has an arc-shaped configuration so as to act as feeding hopper in which the material coming from the pick-up unit (22) is discharged.

12. Machine according to claim 10 or claim 11 , wherein said second drum (76) is provided on the outer surface thereof with a plurality of cutting or conveying elements (82), arranged in particular along a spiral-shaped path so as to convey the material towards the centre of said second drum (76).

13. Machine according to any one of the preceding claims, wherein said conveying means (80) comprise a belt, in particular a perforated belt.

14. Machine according to any one of the preceding claims, wherein the pick-up unit (22) is detachably connected to the arm (28), to allow operation of the machine with the collecting unit (24) and the conveying unit (26) only, i.e. without the pick-up unit (22).