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Title:
AN AUTOMATIC MACHINE FOR NON-CONTACT SORTING
Document Type and Number:
WIPO Patent Application WO/2014/076719
Kind Code:
A2
Abstract:
The present invention relates to an automatic machine for non-contact sorting of the type comprising a load-bearing structure (2), built using profiles made of a metallic material, envisaged to house therein a pair of stations, namely a piece supply unit (3) and a piece control unit (4). The machine is recommended for checking for the presence of defects in rubber articles. It features notable viewing precision, working on both sides of the piece simultaneously, and high resolution working in an extremely fast and considerably improved manner.

Inventors:
SALVA DANIEL OSCAR (IT)
Application Number:
PCT/IT2013/000307
Publication Date:
May 22, 2014
Filing Date:
November 07, 2013
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
DOSS VISUAL SOLUTION S R L (IT)
International Classes:
B07C5/02
Foreign References:
US20110209968A12011-09-01
EP1518611A22005-03-30
EP1577024A12005-09-21
DE4129142A11992-03-05
Attorney, Agent or Firm:
MALGARINI, Lucia (8/H, Goito, IT)
Download PDF:
Claims:
CLAIMS

1 ) An automatic machine for non-contact sorting characterised by the fact that the said machine comprises a load-bearing structure (2), built using profiles made of a metallic material, envisaged to house therein a pair of stations, namely a piece supply unit (3) and a piece control unit (4), wherein the piece supply unit (3) comprises:

a storage area (30), connected to an elevator belt (3 1 ) which is envisaged to pick up the pieces to be sorted from the storage area (30) and move them in bulk, using a conveyor belt (32) which features a brush (33) envisaged to flatten out the pieces and convey them to a first rotating partition (34) which aligns the pieces and sends any surplus pieces to the storage area;

a second partition (37), located on the conveyor belt (32) and envisaged to guide the pieces towards a second conveyor belt (36), which conveys them towards a sandwich belt (38) that catches, retains, accelerates, and accompanies the pieces, separates them one by one, and then lets them fall towards the control unit (4), which is comprised of: an optical inspection unit constituted of a pair of in-line video cameras (40a and 40b), located one in front of the other, in a mutually opposing position along the same axis of alignment, the said video cameras visually ' capturing' each piece and reading the condition of the surface thereof, thereby allowing a high-resolution view of both sides of each piece at the same time;

a pair of lighting units, respectively (41 a and 41 b), supplied with each camera, wherein the said lighting units are located in front of the respective camera and are envisaged to light up one another, the said two lighting units (41 a and 41b) having mutually different emission colours so as to allow each lighting unit to operate with its respective video camera and not to interfere with or disturb the other;

a planarity/thickness device located before the optical unit, comprising a laser sensing blade which is able to read the thickness and/or planar deformation of the piece and send the data read to the management and control means;

a conveyor (45) with a Y-shaped configuration envisaged to receive the individual pieces after the passage thereof in front of the video camera and to direct them towards either a first guide (46), which leads to a recipient for the compliant pieces, or to a second guide (47), which leads to a recipient for the rejected pieces, the said conveyor featuring a blade that moves, either closing a guide and opening the passageway to the other guide or vice versa, depending on whether the piece is compliant or rejected, and the blade's movement is controlled by the management and control means, which send the order to accept or reject the piece based on the result of processing of the video camera viewing/detection data;

a first photocell, located between the lighting units, which signals the arrival and passage of the piece in order to allow the video camera to perform the scan and then send the detected image to the management and control means, the said image being then processed and the result of the examination drawn up, and a second photocell, located below the first, which receives information from the management and control means and governs acceptance or rejection of the piece by moving the conveyor blade (45);

a viewing system which allows an operator to view the images captured by the video cameras on a screen, the said screen being a touch screen so that the operator can easily enter all the necessary data and all the instructions required by the machine to perform all the actions for sorting the pieces;

the said machine comprising:

management and control means for coordinating and managing all the activities of the two stations;

Internet access for remote support and a USB port in order to add programs or updates;

a peripheral piece control system to view the outer part of the piece, i.e. the piece joint section.

2) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said elevator belt (31) is driven by an electric motor (31 a), the said conveyor belt (32) is driven by an electric motor (32a), and the said second conveyor belt (36) and the said sandwich belt (38) are driven by an electric motor (39), the said brush (33) is driven by an electric motor (33a) and the two partitions (34 and 37) are each driven by a motor, respectively (34a and 37a).

3) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said machine comprises a stream of deionised air that facilitates the passage of the pieces from the elevator belt (31 ) towards the conveyor belt (32), as well as the distribution thereof on the said belt when the pieces reach the end of the route along the elevator belt (3 1 ).

4) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said storage area (30) has a 50-litre capacity but there is a possibility of connecting it to an external supply unit to increase the capacity to approximately 210 litres, the said external supply unit, when operational, being managed from the storage area (30), where the flow of pieces from the external supply unit is activated and/or stopped according to requirements.

5) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said sandwich belt (38) features pulleys which allow the creation of the route desired for the belt, wherein a first pulley is fixed, while a second can flex slightly to allow dispersion of the belt speed and the distance between the belts to be altered to allow the passage of thicker pieces.

6) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that each video camera has a fixed setting, since it has good depth of field and it self-adjusts by adjusting the focus when the pieces are either very thin or very thick.

7) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that each lighting unit presents a quadrangular external structure built with a metallic material, preferably aluminium, inside which there is a hollow seat containing thousands of LEDs, arranged around multiple circumferences and covering the entire surface of the hollow seat, which is protected by an opalescent screen endowed with a horizontally positioned rectangular slot which meets the operational need of the video camera, each lighting unit having a strip of LEDs to serve as rear lighting and as backlight for the video camera opposite.

8) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said machine comprises an emitter, managed by the management and control means, which sends out an on/off command at intervals, providing a strobe function.

9) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the recipient of the compliant pieces is well separated from the recipient of the rejected pieces, so as to prevent the falling rejected pieces bouncing into the recipient of the compliant pieces.

10) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said machine envisages the presence of an external "lung" which allows the pieces to be sent to another recipient, with a greater capacity, or to a device for packaging, or towards other processing areas, the said "lung" being a suction device or a conveyor belt which transfers the pieces.

1 1 ) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said load-bearing structure (2) is envisaged with chamfered corners, protective panels, and rubber seals to prevent possible injury, the said structure being sealed by protective Plexiglas panels that protect the supply unit (3) and control unit (4), since there are moving pieces, such as the brush, the partitions and the various belts, and the said protective sealing panels being antireflective to limit entry of external light, which could affect the internal visual conditions and proper video camera operation, the said load-bearing structure also envisaging the presence of a signal light comprising a pair of lights (one red, the other green) in traffic light fashion, the first of which signals machine stoppage with problems, while the second shows that the machine is operating properly, and the presence of assistance photocells which stop the machine when any of the protective panels of the structure are opened.

12) An automatic machine for non-contact sorting according to claim 1 , characterised by the fact that the said machine is powered by an electric current and the load-bearing structure (2) features a housing for all components of the electrical system assigned to power the motors and the management and control means, and in both the units (3 and 4) and inside the load-bearing structure (2), there are no free wires, since the bundles of electric wires are enclosed in special housings.

Description:
"A UTOMATIC MACHINE FOR NON-CONTACT SORTING" The present invention relates to an automatic machine for non-contact sorting which is particularly recommended for checking for the presence of defects in rubber articles.

As it is well known, until not long ago, the monitoring of rubber products such as, for example, rings or seals, but also those with a complex form, was carried out by hand, with the obj ects simply handled by workers who, over time and with experience, developed a highly trained eye, capable of detecting imperfections on the surface of the piece to be assessed.

The need to obtain ever-better results in terms of precision and to alleviate the notable strain placed on the workers, who - in the long run - lose visual capacity, resulting in less precise and slower workers, has led to the creation of automatic vision systems featuring equipment which, by means of a video camera, performs the action previously performed by the human eye.

The equipment currently available on the market is of the contact type, i.e. the piece rests on a surface or is retained by a robotic element, which means the checking for defects requires a certain amount of time and productivity is rather low. Furthermore, when the pieces are made of static materials, productivity drops still further because the handling thereof is even slower. Additionally, when it is necessary to view the other side of the piece, it is necessary to turn it over, a condition which results in a still further reduction in productivity. As mentioned earlier, existing machines permit viewing of the piece on one side only, which means the possibility of having pieces which do not comply with requirements is extremely high, nearing 50%. In particular, existing machines have shown difficulty in managing the pieces as they have to view different-sized pieces, which means, for example, that when they are very small, with an external diameter of 10 mm, and are very light, the machine has shown difficulty in conveying the pieces without them jumping and dispersing.

Another problem encountered with the machines available on the market is due to the fact that they are fairly large in size, which means they are bulky and difficult to handle and manage. In fact, the aforesaid machines feature a structure which contains massive, very heavy components, which means the said structure is subject to greater wear and more frequent breakages when the machine is opened.

Furthermore, because of the shape thereof, the structure of existing machines does not meet accident-prevention regulation requirements, as the structure is so heavy and features sharp edges which are hazardous for workers who interact with the machine.

Furthermore, every time it is necessary to access the inside of the machine for replacement or maintenance purposes, it is necessary to dismantle the machine, disassembling diverse parts which must then be refitted, resulting in longer maintenance times, time wasted during production as a result of downtime, and running costs which impact on the overheads. A further but not final problem encountered with existing machines is that they are not usable by handicapped persons since such persons are unable to access the controls or the other, however simple, functions of the machine.

The aim of the present invention is essentially to solve the problems of the known technique by overcoming the difficulties described above by means of an automatic machine for non-contact sorting which can offer notable piece viewing precision, with high resolution, working on both sides thereof simultaneously.

A second aim of the present invention is to provide an automatic machine for non-contact sorting capable of permitting the viewing of the pieces without contact in an extremely fast manner and with improved productivity.

Another object of the present invention is to have an automatic machine for non-contact sorting which is structurally simple and is extremely functional, easy to maintain, and compact in size.

A further aim of the present invention is to have an automatic machine for non-contact sorting which is capable of sorting from a few to very many pieces and which can also be used by disabled workers.

A further but not final aim of the present invention is to have an automatic machine for non-contact sorting which can contain production, running, and maintenance costs, in addition to allowing energy saving in consumption terms. A still further but not final aim of the present invention is to produce an automatic machine for non-contact sorting which is easy to manufacture and works well.

These aims and others besides, which will better emerge over the course of the present description, are essentially achieved by means of an automatic machine for non-contact sorting, as outlined in the claims below.

Further characteristics and advantages will better emerge in the detailed description of an automatic machine for non-contact sorting according to the present invention, provided in the form of a non-limiting example, with reference to the accompanying drawings, in which:

- Figure 1 shows, schematically and from a perspective view, an automatic machine for non-contact sorting according to the present invention;

- Figure 2 shows, schematically, a frontal view of the machine in Figure 1 ;

- Figure 3 shows, schematically, a top view of the machine in Figure 1 ;

- Figure 4 shows, schematically, a side view of the machine in question;

- Figure 5 shows, schematically, a further side view of the machine according to the present invention;

- Figure 6 shows, schematically, a detail of the machine in Figure 2;

- Figure 7 shows, schematically and from a front perspective view, the containment structure of the machine in question; - Figure 8 shows, schematically and from a rear perspective view, the containment structure of the machine in Figure 1 .

With reference to the aforesaid figures, and in particular Figure 1 , n. l denotes an automatic machine for non-contact sorting as a whole, according to the present invention.

The machine 1 is essentially composed of a load-bearing structure 2 built using profiles made of a metallic material, preferably aluminium, envisaged to house therein a pair of stations, namely a piece supply unit 3 and a piece control unit 4.

The piece supply unit 3 comprises a storage area 30 which is connected to an elevator belt 31 which is envisaged to pick up the pieces to be sorted at the storage area 30 and move them, in bulk, on a conveyor belt 32, which features a brush 33 provided to flatten the pieces, conveying them to a first rotating partition 34. The first partition 34 aligns the pieces and sends any surplus pieces to the storage area. The pieces transit on the conveyor belt 32, which carries them towards a second partition 37, which is envisaged to convey them towards a second conveyor belt 36, which transports them to a sandwich belt 38, which captures, accelerates, and accompanies the pieces, separating them one by one before they are released near the control unit 4.

More in detail and as shown in Figure 1 , the elevator belt 31 is driven by an electric motor 31 a, the conveyor belt 32 is driven by an electric motor 32a and the second conveyor belt and the sandwich belt 38 are driven by a electric motor 39. Similarly, the brush 33 is driven by an electric motor 33a, while the two partitions 34 and 37 are driven, respectively, by a motor 34a and a motor 37a.

In addition to the explanations so far, when the piece reaches the end of its route on the elevator belt 31 , it is helped in the passage to the conveyor belt 32 by a jet of deionised air, which facilitates the passage of the pieces from one belt to another and the distribution thereof on the belt 32, an extremely useful aid, especially when there are pieces with a high friction level.

According to the present embodiment, the storage area has a capacity of 50 litres, but there is a possibility of connecting it to an external supply unit to increase the capacity to up to approximately 2 10 litres.

In greater detail, the operations of the external supply unit are managed by the storage area 30, which activates and/or stops the flow of pieces from the external supply unit, based on requirements.

In particular, the pieces that fall off due to the action performed by the brush 33 are retrieved and collected in the storage area 30, ready to be placed back on the elevator belt 3 1 .

In addition to the explanations so far, the sandwich belt 38 features pulleys which permit the creation of the route desired for the belt, wherein a first pulley is fixed, while a second can flex slightly to allow dispersion of the belt speed and the distance between the belts to be altered to allow the passage of thicker pieces. In detail, the sandwich belt 38 has the task of retaining the pieces and conveying them to the point at which they free fall, vertically, into the control unit 4, as explained below. In accordance with the present invention and as shown in Figure 2, the machine 1 comprises a piece control unit 4 composed of an optical inspection unit consisting of a pair of video cameras 40a and 40b, of a linear type. In greater detail, the linear video camera is an image acquisition device whose sensor is formed of a single line of photosensitive elements (pixels). Therefore, acquisition is carried out line by line. Each scan line can be considered a kind of one-dimensional mapping of the brightness of the individual points of the observation line. Linear scanning generates a line whose Y axis shows the brightness of each point in levels of grey (0 to 250 levels). A sudden change in the grey level of a single point corresponds to a point in the outline of an object or, in any case, to the presence of a variation in colour or appearance. Detecting this variation, therefore, permits a high-precision measurement to be obtained, which is also permitted by the high resolution of the linear sensor. This way, it is possible to detect imperfections on any surface and therefore establish the condition of the individual pieces to be sorted.

Additionally, the video cameras 40a and 40b are housed one front of the other, as shown in Figure 2, and are positioned in a mutually opposite fashion, and have the same axis of alignment.

During the piece falling stage, once the sandwich belt 38 has released the piece and dropped it, the piece is "captured" visually by the two video cameras 40a and 40b, which scan the condition of the surface thereof. Each video camera has a fixed setting, since it has good depth of field and, furthermore, it self-adjusts by adjusting the focus when the pieces are either very thin or very thick.

In particular, each video camera is equipped with a lighting unit, respectively 41 a and 41 b, which is positioned in front of the respective video camera and the lighting units are responsible for lighting up one another. According to the present invention, the two lighting units 41 a and 41 b have mutually different emission colours. This permits each lighting unit to operate with its own video camera without interfering with or disturbing the other. The presence of the two video cameras permits the viewing of both sides of each piece simultaneously.

In greater detail, each lighting unit features a quadrangular external structure built with a metallic material, preferably aluminium, inside which there is a hollow seat containing thousands of LEDs, arranged around multiple circumferences and covering the entire surface of the hollow seat, which is protected by an opalescent screen endowed with a horizontally positioned rectangular slot which meets the operational need of the video camera.

Additionally, each lighting unit has a strip of LEDs to serve as rear lighting and as backlight for the video camera opposite.

The lighting units are managed by management and control means, and there is an emitter, which is also managed by management and control means which send out the on/off command at intervals, with a strobe function. This intermittent light emission system means it is possible not to have the lighting unit always on, with a reduction in power consumption and consequent energy saving, and to have lower LED wear, which means less maintenance work required for replacement of the said LEDs. Furthermore, this makes it possible to have better video camera vision and operations.

Additionally, the control unit 4 is endowed with a planarity/thickness device located before the video cameras, comprising a laser sensing blade which is able to read the thickness and/or planar deformation of the piece and send the data read to the management and control means. In accordance with the present embodiment, the control unit 4 comprises a conveyor unit 45 with a Y-shaped configuration envisaged to receive the individual pieces after the passage thereof in front of the video camera and to direct them towards either a first guide 46, which leads to a recipient for the compliant pieces, or to a second guide 47, which leads to a recipient for the rejected pieces. The conveyor features a blade which moves, either closing a guide and opening the passageway to the other guide or vice versa, depending on whether the piece is compliant or rejected. The blade's movement is managed by the management and control means, which send the order to accept or reject the piece based on the result of processing of the video camera viewing/detection data. In fact, after accurate control and verification processing, the management and control means send out piece compliancy or rejection signals.

The control unit 4 comprises, likewise, a first photocell, located between the lighting units, which signals the arrival and passage of the piece in order to permit the video camera to perform the scan and then send the detected image to the management and control means, the said image being then processed and the result of the examination drawn up, and a second photocell, located below the first, which receives information from the management and control means and governs acceptance or rej ection of the piece by moving the conveyor blade 45.

In particular, the recipient of the compliant pieces is well separated from the recipient of the rejected pieces, so as to prevent the falling rejected pieces bouncing into the recipient for the compliant pieces.

If the external supply unit is featured, the recipient for the compliant pieces must be proportional so as to be able to contain a greater quantity of pieces. The recipient for the rejected pieces, meanwhile, is normal in size because the rejects generally amount to approximately 5% of the pieces viewed, which means the said recipient has to house a limited number of pieces with respect to the number of compliant pieces.

In accordance with the present invention, the machine includes a machine stop function which activates when a high percentage of rejects is encountered. In fact, after a preset number of pieces are rejected consecutively, the machine stops (for example, ten consecutive pieces) to permit the worker to check why there is such a high number of rejected pieces. Furthermore, there is another machine stop function activated when the pieces reach a preset volume inside one of the two recipients, to allow replacement of the recipient or the emptying thereof. In addition to the explanations so far, the control unit 4 includes a vision system which permits an operator to view on a screen that which the video cameras have detected. In greater detail, the screen is of the touchscreen variety so that the operator can easily enter all the necessary data and all the instructions required by the machine to perform all the actions constituting the sorting of the pieces. Furthermore, the operator can find diverse menus on the screen for setting the defects to be identified. In particular, it is possible to save everything as an article code and each batch which is sorted and viewed is saved by the management and control means. In particular, it is possible to generate statistical documents, which means even the size of the piece is checked. There is a visual and dimensional control process, with the preparation of statistical reports on checks carried out. Additionally, when checking for defects, there is also a defect size and type control process.

Furthermore, the machine has Internet access for remote support and there is a USB port present in order to add programs or updates.

In accordance with the present invention, the machine may have an external "lung", which makes it possible to send the pieces to another container with a greater capacity or to equipment for packaging or on for other processing. The "lung" may be an aspirator or a conveyor belt which transfers the pieces.

The machine may envisage a peripheral piece control system for viewing the outer part of the piece, i.e. the piece joint section.

In accordance with the present embodiment, the load-bearing structure 2 is provided with chamfered corners and wherever this is not possible, there are guards designed to prevent possible accidents. Furthermore, as shown in Figure 7 and in Figure 8, the load-bearing structure 2 is sealed by protective Plexiglas panels which protect the supply unit 3 and control unit 4, since there are moving pieces, such as the brush, the partitions and the various belts.

The said protective sealing panels are antireflective to limit entry of external light, which could affect the internal visual conditions and proper video camera operation.

Additionally, the edges of the upper covers of the load-bearing structure 2 also feature rubber strips so that when there are panels open, especially the upper ones, even if an operator should simply hit his head, the blow would be dampened and decidedly lessened.

The machine is endowed with assistance photocells, with the result that when any of the protective panels of the structure are opened, the machine stops.

According to the present embodiment, the load-bearing structure envisages the presence of a signal light comprising a pair of lights (one red, the other green) in traffic light fashion, which signal, respectively, machine stoppage (with problems reported) and proper machine operation.

The machine is powered by electric current, and within the load-bearing structure 2 there is a housing for all the electrical system components assigned to power the motors and the management and control means. In particular, both in units 3 and 4 and inside the load-bearing structure 2, there are no loose wires since the groups of electric wires are enclosed within appropriate housings. In the present embodiment, the computer and the monitor screen are housed at a height which is also accessible to a handicapped operator, who can manage the machine's operations and is also able to go so far as to load pieces in the storage area, even though Italian Law n. 626 envisages that such persons should not lift weights; furthermore, a disabled worker can also easily access the recipients for the rejected pieces and the compliant pieces in order to carry out checks.

With the machine in question, it is possible to view and control the two sides of a piece, process the results, keep the compliant pieces (conveying them into a suitable recipient) and discard the non-compliant pieces (setting them aside in another recipient.

After the predominantly structural description above, the operation of the invention in question will now be outlined.

When an operator has to sort a batch of pieces, they simply have to put the said pieces in the storage area, then, using the screen, enter the necessary data and set the parameters to be met in relation to the defects to be detected and the tolerances to maintain, and then activate the machine.

At this point, the management and control means actuate the motors that move the belts, the brush, and the partitions, which means the pieces are gradually taken up by the elevator belt, which carries them into position with the conveyor belt on which they are carried loose and positioned in a reciprocally overlapping fashion, aided by the air jet which facilitates their passage from one belt to another and then the conveyor belt moves them towards the brush, which flattens them and divides them, making the surplus pieces fall into the storage area from where they will be taken up once again by the elevator belt to be carried back to the conveyor belt.

The pieces that remain on the conveyor belt end up encountering the first partition which has the task of aligning the individual pieces, which are transported up to the second partition, which guides them toward the first belt which, in turn, brings them up to the sandwich belt, which captures each piece between the two belts and carries it up to the point at which the belt releases the said piece, causing it to fall vertically. At the moment in which the piece detaches from the sandwich belt, the first photocell intercepts the piece and signals the passage to each video camera, which means the corresponding lighting unit switches on, emitting light and permitting the scanning of the two sides of the piece. After scanning, the management and control means process the data collected and send a piece compliance or rejection signal to the second photocell, which manages the acceptance or rejection of the piece by moving the conveyor blade.

Having reached this point, if the piece is found to comply with the parameters entered, it will fall into the recipient for compliant pieces, otherwise it will end up, through the second guide, in the reject recipient.

Once the whole batch of pieces is finished, the operator will simply have to eliminate the rejected pieces and send the compliant pieces to a packaging machine or on for other processing. The operator may obtain a report stating the number of rejects, classified by individual criteria, and the number of compliant pieces and other information, and also reports containing information, statistics, tables of the results measured and the types of defects, etc. In the event that a fault occurs during machine operation the signal light comes on with the red light, which signals the anomaly and a corresponding message appears on the screen Thus the present invention achieves the aims set.

The automatic machine for non-contact sorting according to the present invention offers notable piece viewing precision, with high resolution, working on both sides thereof simultaneously.

Furthermore, the machine makes it possible to scan the pieces without any contact in a extremely fast manner and with improved productivity, unlike as happens with the machines according to the commonly known technique.

Advantageously, the machine features a notable ease of setting, is structurally simple, extremely functional and extremely flexible, since it makes it possible to work, without problems, on small to considerable quantities of pieces.

In particular, the machine is compact, of contained dimensions, and makes it possible to have an interesting level of energy savings, which turns into more contained production costs; it offers easy access and maintenance, a situation which makes it possible to perform component replacements in very little time, in the simplest of manners, and without the need to disassemble major parts of the machine, as occurred with those according to the commonly known technique. In addition to the explanations so far, the machine in question permits optimal use, for example, in the pharmaceutical industry as it is easily cleanable and features no areas of accumulation of dust, since there are no sudden movements of the air, unlike as occurs with existing machines.

In fact, it is extremely simple to keep the machine clean, as all parts thereof are completely openable and accessible.

With the machine according to the present invention, it is possible to contain production costs (as the said machine is simpler and more compact), running costs (as it allows energy saving), and maintenance costs (since the components do not need to be disassembled and reassembled, resulting in both time and labour savings with repercussions on the overheads).

Additionally, the machine can be easily and readily usable even by personnel with a handicap, since both the management and control means and the monitor are extremely convenient and within reach and are at a height which renders them accessible, including therein by a person in wheelchair.

Advantageously, the machine in question is structurally simple, extremely functional, safe and precise, and able to carry out the sorting of pieces in a quick and highly precise manner.

Advantageously, the handling of the components remains constant over time, without deformation and with extremely limited wear. Furthermore, maintenance proves much easier and faster and can be performed with simple operations as the components subject to maintenance prove to be all easily accessible.

A further but not final advantage of the present invention is that it proves remarkably easy to use and to manufacture and works well.

Naturally, further modifications or variants may be applied to the present invention while remaining within the scope of the invention that characterises it.