EP2105217A1 - Method and installation for quality control through visiometric inspection - Google Patents

Abstract

The installation has a visiometric post (2) having processing units that process associated image to automatically deduce product localization information. Transfer units transfer products scrolling in a primary conveyor (A) to a secondary conveyor (C). Visiometric examination realization units (3) individually validate gripping of the products by pneumatic gripping devices. Control units control distribution of the products in an outlet of the conveyor (C) according to product counting information deducted from products gripping validation information. An independent claim is also included for a method for sorting scrolling products e.g. industrial bakery products.

Description

The present invention relates to the quality control of discrete products brought on a conveyor causing them to scroll from one to the other of successive positions in an industrial installation. It finds application preferentially, although not exclusively, in any situation where it is sought to sort the products according to predefined quality criteria, especially with a view to their packaging in separate batches of predefined size for delivery, out of a production line. In the following, therefore, the concept of control will encompass not only everything that falls within the scope of a quality control as referring to individual characteristics of each product, but also all that relates to a collective control of counting to collect and / or group batch products containing them in predefined quantities.

As an example, in the field of industrial bakery, it is known that products driven in a conveyor are routinely subjected to visiometric examinations, and that, depending on the results of these examinations, they are assigned quality attributes after which it is then decided their distribution out of the conveyor. Thus, in particular, the products conveyed by the conveyor are distributed according to predefined quality criteria such as their shape, their dimensions, their color, and / or that these products are distributed according to their batch batch counting.

If only for an economic purpose, it is desirable to reduce the time required for these control operations. In addition, the speed of online control is of particular importance when the products to be processed are in chilled or frozen form, which is frequently the case in the food industry. Similar requirements occur whenever the exposure of the products during the visiometric examination is likely to affect the conditions of good conservation imposed on them.

By the method and the installation which it proposes, the present invention allows a simple and fast sorting of the products under conditions allowing a more complete examination of the products, by the fact that they are examined twice, once. from above, once per the underside during a transfer between two conveyors on which they are conveyed deposited on conveyor belts or similar systems.

Examination from above is in itself conventional for so-called short products (rolls and pastries) which are conveyed deposited on a conveyor belt and directly sorted at the outlet of the conveyor. But techniques of this type are very difficult to sort of so-called long products, such as bread sticks. In particular, they should be perfectly arranged one behind the other and all perpendicular to the direction of movement through the visiometry station so that it can operate validly an output device whose door is temporarily closes each time it has missed the desired number of products for a lot of packaging. This is, in practice, almost never the case. By using an individually controlled multi-gripper seizure device, in particular of pneumatic type, according to preferred features of the invention, it becomes possible to effectively treat long products, even poorly arranged on a primary conveyor. It is known to make suitable gripping devices from suction grippers. The input of the products is then controlled by selectively activating only those suction cups which are useful for gripping a product as a function of its location on the conveyor belt in the area covered by all the suction cups of the gripping device. Standard level quality control examinations may be performed at the primary conveyor so as to control the pneumatic gripping of each particular product provided that it is judged to be compliant in quality.

When sorting is so designed, however, there is a secondary problem with batch counting and batch sorting. This problem stems mainly from deficiencies which are specific to the operation of the individually controlled multiple gripper systems, in particular, firstly, in terms of accuracy in the determination of the grippers to be activated in seizure, in correspondence with the products to be seized, and of on the other hand, in terms of malfunctions of the individual grippers. The resulting errors in counting the number of products retained can be particularly serious when it comes to long products, even though these errors could be tolerable in the case of short products.

The invention particularly relates to an installation applying in a nonlimiting manner to the sorting of products in industrial bakery, installation comprising several conveyors conveying the products and which has the particularity of the presence of a pneumatic gripping device for transporting said products. a primary conveyor to a secondary conveyor. It extends to a method of sorting discrete products moving on a primary conveyor and transferred to a secondary conveyor from which they are then distributed to the output stations of the installation.

According to one of its features, the installation according to the invention comprises a first visiometric examination station products scrolling on the primary conveyor. The upper face of the products is here examined, and a product location information on the conveyor is deduced. This location information may, for example, take the form of coordinates of the products in the plane defined by the primary conveyor, on a predefined area thereof, chosen according to the capacity of the means used for pneumatic gripping and transport. .

The invention in fact provides that this location information is then used to control pneumatic means for capturing at least some of the products present on this predetermined area of the primary conveyor, input means which are part of a device for transferring data. seized products which deposits them on a secondary conveyor.

In addition to the location information, the examination of the upper face of the products in the first visiometric examination station can be used to derive shape, size, and / or surface state characteristics of each of them. these products, and thus automatically assign each of these, based on a comparison of these characteristics with a set of predefined criteria, a first quality attribute.

In this case, the input of the products on the primary conveyor is then controlled on the combined basis of the location information and quality attributes assigned to the products during the first visiometric examination as just indicated.

According to another characteristic of the installation according to the invention, the means for gripping and transferring the products from the primary conveyor to the secondary conveyor comprise a plurality of pneumatic gripping devices individually controlled in gripping and release of said products, and advantageously arranged to constitute a mesh in two dimensions covering an area chosen according to the shapes and maximum dimensions of the products to be controlled and sorted as well as according to the control and sorting rates concerned. This area is advantageously, in practice, that which is used for determining the area of the primary conveyor on which are acquired, in the first visiometric station, the images of the upper face of the products from which are deduced the location information of said products. For the sake of clarity, the term "gripping matrix" will be used hereinafter to denote all the grippers thus disposed.

More specifically, each individual pneumatic gripper comprises a suction cup connected to a vacuum circuit, as well as blowing means in this suction cup. Each gripper is thus able to grab a product by suction by the suction pad that it includes and to release this product by blowing into the same suction cup.

The blowing is preferably obtained by injecting, in the suction cup of the gripper concerned, a flow of gas from a pressurized gas supply circuit which is connected to the suction cup by appropriate means. It should be noted, however, that if, in a preferred embodiment of the invention, this pressurized gas supply circuit is connected to a compressor, it is sufficient that the pressure supplied is equal to the ambient atmospheric pressure to allow the release of a product previously grasped by aspiration.

The switching of each gripper from its release state to its gripping state of a product is achieved by closing a normally open injection valve placed on the pressurized gas feed circuit of the gripper, which closure has as a result the connection of the suction cup with the single vacuum circuit. The injection valve being normally open, it follows that the gripper is, by default, in its state of release of a product.

According to a preferred embodiment of the invention, several grippers of the type which has just been briefly described are grouped into modules and a gripping matrix consists of at least one, preferably several similar modules. According to a preferred embodiment of the invention, each module of a matrix is formed of a set of suction grippers of the type summarily described above, of a common vacuum chamber to which the grippers are connected, and a common feed chamber with pressurized gas. Advantageously, the vacuum chambers of each of the modules of the matrix are each connected to a common pumping pipe, which is itself connected to a general pumping device of appropriate dimensions to enable a shallow vacuum to be reached in the said vacuum chambers. . Common vacuum chamber and common pumping line thus constitute the vacuum circuit of each gripper module.

According to another of the features of the invention, a second visiometric examination is performed on the underside of the products held suspended grippers during movement of said products between the primary conveyor and the secondary conveyor.

For this purpose, a camera, preferably a linear camera, is placed between the primary conveyor and the secondary conveyor, on the fraction of the path of the products being transferred where they are suspended above the vacuum. The camera in question is programmed to capture images from the underside of the products and to deduce an individual validation information from the input, confirming whether each product has actually been grasped by the grip matrix and transported with it until it is deposited on the secondary conveyor.

The invention provides that this validation information is then used by counting means to automatically control the distribution of the released products on the secondary conveyor.

In a complementary manner, information of size, shape, color or texture, relating to the underside of the products (detecting the presence of stains or information indicating the cooking quality for example) can be deduced from these images. , then compared to a set of predefined parameters to automatically assign to each product.

In this case, this attribute of quality can then be used to release and / or to distribute the output products of the secondary conveyor for their batch grouping of predefined size, for example for their packaging and shipping.

The invention presents in this case an additional advantage in that it allows the realization of a complementary quality control in masked time during the displacement of the gripping matrix towards the secondary conveyor, thus contributing to optimize the cycle time of manufacture of products.

• la figure 1 est une vue schématique de dessus des différents éléments d'une installation de contrôle et de tri selon l'invention,
• les figures 2A à 2D sont des vues schématiques de dessus de l'installation selon l'invention, illustrant le procédé selon l'invention dans un de ses modes de réalisation dans lequel deux matrices de préhension sont associées à un convoyeur primaire et à un ensemble constitué de deux convoyeurs secondaires et de plusieurs bacs de rejet,
• la figure 3 est une vue schématique de dessus illustrant la saisie sélective de produits par les préhenseurs d'une matrice,
• et la figure 4 est une vue schématique en coupe d'un module de préhenseurs de l'installation selon un mode de réalisation préférentiel, mais non exclusif, de l'invention.

These and other advantages will emerge more clearly on reading the following description of a preferred embodiment, but not limiting of the invention, with reference to the following figures in which:

• the figure 1 is a schematic view from above of the different elements of a control and sorting installation according to the invention,
• the Figures 2A to 2D are schematic views from above of the installation according to the invention, illustrating the method according to the invention in one of its embodiments in which two gripping matrices are associated with a primary conveyor and a set of two secondary conveyors and several bins of rejection,
• the figure 3 is a schematic view from above illustrating the selective seizure of products by the grippers of a matrix,
• and the figure 4 is a schematic sectional view of a gripper module of the installation according to a preferred embodiment, but not exclusive, of the invention.

For clarity in the description that follows, define an orthonormal reference (XYZ) with reference to the position of the installation on the ground. In this frame, the X and Y axes define a horizontal plane, and the Z axis represents the vertical direction. Similarly, for clarity, the identical elements are designated by the same references in the various figures.

With reference to the figure 1 , the installation according to the invention comprises a primary conveyor A on which are scrolled the products to be controlled and sorted collectively designated by the reference B. The installation according to the invention also comprises at least one secondary conveyor C and a pneumatic gripping device 1 consisting of a set of grippers P (see figure 4 ) individually controlled to seize products on the primary conveyor A, transfer them to the secondary conveyor C, as well as to release the seized products. The installation according to the invention therefore also obviously includes electronic means programmed to control and manage the various elements that constitute it.

According to the particular, nonlimiting embodiment of the invention represented by the figure 1 in which the products to be sorted have the shape of bread sticks B, these are preferably oriented in a direction substantially parallel to the Y axis of the orthonormal coordinate system (XYZ) and arranged in a direction substantially parallel to the X axis of the same landmark. It should be noted that the products can be arranged in a predefined order, or be arranged randomly on the conveyor A without damaging the invention.

The primary conveyor A runs parallel to the axis X, in the direction represented by the arrow F on the figure 1 . The conveyor belt A, on which the products are arranged, scrolls in a horizontal plane parallel to the plane (XY) of the orthonormal coordinate system (XYZ).

The conveyor C extends here parallel to the conveyor A and it drives the products in a direction parallel to the scrolling direction F of said primary conveyor A.

However, it should be noted that the invention makes it possible to give the secondary conveyor any orientation with respect to the primary conveyor, only the distance between these two conveyors with respect to the movement capabilities of the gripping device. pneumatic being to be taken into account in the respective arrangement of these two conveyors. Thanks to this feature of the invention, only the optimization of the size of the production line and the rationalization of it govern the configuration of the installation and the implementation of its conveyors. The invention has an additional advantage here, in that it allows a maximum flexibility of the arrangement of the conveyors of the installation which is its object.

According to an advantageous embodiment of the invention, the various conveyors are of the type comprising carpets whose meshes can be interpenetrated between them longitudinally, also known under the designation of "modular belt conveyors". The introduction of an appropriate motorization then makes it possible to create, on the same conveyor, areas of compressed meshes and stretched mesh areas. This makes it possible to obtain, on the same conveyor, a modulation of the instantaneous flow of products traveling in different longitudinal regions thereof. Thus, the primary conveyor can serve as a ramp for routing products in successive waves to the gripping device 1, and the secondary conveyor or the same type as the primary conveyor, receive said products in waves and can be motorized in such a way that they transform these successive waves into a continuous stream of products at the exit of the conveyor.

Each gripper P of the pneumatic gripping device 1 comprises a suction cup 10 and means for connecting this suction cup to a vacuum circuit (see FIG. figure 4 ). Each of the grippers P is thus able respectively to grip a product by suction by means of its suction cup 10, and to release a product that is blown into said suction cup 10. This blowing is carried out by injection, into the suction cup 10, of a gas under pressure from a suitable supply circuit.

Furthermore, the grippers P are, according to a preferred embodiment of the invention, grouped into modules M together forming the pneumatic gripper device 1, also referred to herein as a gripping matrix. In this gripping matrix, the suction cups of the different grippers form a two-dimensional mesh of a predetermined area surface.

According to the embodiment more particularly illustrated by the figure 4 , the suction cups 10 of each of the grippers P of a module M are all connected to a common vacuum chamber 11, itself connected by appropriate means to a general pumping device 12 schematically shown on FIG. figure 4 . The connection between the vacuum chamber 11 and the general pumping device 12 comprises at least one pipe 13 and a shut-off valve (not shown in the figures) controlled by electronic control and management means of the installation according to the invention. 'invention.

According to this same embodiment, each of the grippers P of a module M is connected to a common pressurized gas supply chamber 14 which is itself connected to a general circuit for supplying pressurized gas 15 schematically shown on FIG. figure 4 . Preferably, but not exclusively, the general supply circuit 15 comprises a compressor 16, not shown in FIG. figure 4 . The connection between the feed chamber 14 and the general supply circuit 15 advantageously comprises at least one pipe 17 and a stop valve controlled by electronic control and management of the installation according to the invention. The connection between each of the grippers P and the common pressurized gas supply chamber 14 comprises a pipe and a normally open injection valve 18 controlled by electronic means such as those mentioned above.

Switching the release state of the gripper P, wherein gas is injected into the suction cup 10, in the gripping state of said gripper P, wherein said suction cup 10 is only in connection with the vacuum chamber 11, is by the closing of the injection valve 18. The latter being normally open, each of the grippers P is, in the absence of any specific command, in its state of release of a product.

According to one of its features, the invention provides that the products driven in motion by the primary conveyor A pass through a first visiometric examination station 2 equipped with one or more cameras (not shown in the figures) capturing images of their upper face. The invention also provides that these images are electronically processed to deduce in particular product location information on the primary conveyor A, for example in the form of coordinates of these products in a predefined area region of the primary conveyor A. Advantageously, an enumeration attribute can be understood in this location information.

According to a preferred embodiment of the invention, the camera (s) of the visiometry station 2 are of the type known under the name of "laser triangulation camera" and the images that it captures from the upper face of the products crossing the station visiometry 2 are also electronically processed to further deduce information relating to specific individual characteristics of the products such as, by way of non-limiting examples, the shape, size, or color thereof. In other words, the images acquired in the first visiometric examination station are processed to automatically deduce a first quality attribute assigned to each product.

According to another characteristic of the invention, the location information is then used, possibly in combination with the first quality attribute which has just been mentioned, to control the gripping matrix 1 to grab a certain amount of information. number of products present on the primary conveyor. The number of products to be seized is also determined according to the number of grippers as well as the shapes and dimensions of the products considered, shapes and dimensions deduced from the location information.

More specifically, it should be noted that, in the case of the preferred application of the invention to industrial bakery products, the shapes and sizes of the products to be grasped are not necessarily identical to the shapes and dimensions of the gripping surfaces of the suction cups. grippers. Such an identity is not sought after, because of the variety of shapes and sizes of such products, whether rolls, baguettes, or pastries such as croissants or pain au chocolat, by example. It therefore appears that, if the seizure of a unitary object of small size and generally cylindrical general shape such as, for example, that of a pastry proves to be relatively easy, the seizure of an elongated object such as, for example, that of a baguette, may be more delicate.

• des informations de localisation des produits sur une aire prédéterminée du convoyeur primaire, informations de localisation déduites des images saisies dans le premier poste d'examen visiométrique 2,
• et de la connaissance de la localisation des ventouses des différents préhenseurs dans la matrice de préhension 1.

The invention then provides, to promote the capture and transport of products, for example of elongate shape, only grippers whose gripping surface of the suction cup has a sufficient intersection with the upper surface of the product to be seized are switched in their state input. In other words, the invention proposes to selectively operate the switching of the injection valves 18 of these grippers from their "open" state (release state, which is the default state) to their "closed" state. (input state), on the combined basis:

• product location information on a predetermined area of the primary conveyor, location information derived from the images captured in the first visiometric examination station 2,
• and knowledge of the location of the suction cups of the different grippers in the gripping matrix 1.

More specifically, an indication relating to the intersection of the gripping surfaces of the suction cups of the different grippers with the upper surface of the products is deduced from this combined information and used to selectively control individually gripping a number of grippers of the gripping matrix 1 for example, since the intersection surface of the grasping surface of the suction cup of a gripper with the upper surface of the product to be grasped situated opposite said suction cup represents more than half of the grip surface of said suction cup .

In the case of elongated products such as bread sticks, this characteristic of the invention leads to the use of several grippers for gripping a product. As a result, the effort to be made by a single gripper to remove the product from the primary conveyor is reduced. This presents a double advantage. Indeed, on the one hand, the force being uniformly distributed over all the grippers used for the seizure of the product, the risk of breakage of it is reduced. On the other hand, the suction force needed to lift the product from the primary conveyor, evenly distributed over all grippers activated for this seizure, is also lower by gripper.

However, the part of the gripping surface of the suction cup which is not facing a portion of the upper surface of the product to be seized is then a source of leakage and pressure build-up in the vacuum chamber of said suction cup .

The embodiment of the invention illustrated in particular by the figure 4 uses an original solution to remedy this problem, the solution whose principle is based on a specificity of the grippers constituting the gripping matrix in this particular embodiment.

According to this embodiment, the pressurized gas supply circuit of each of the grippers P forms, in the vacuum chamber 11 of each of the gripper modules, a Venturi tube whose suction occurs in said vacuum chamber. . When the injection valve 18 is open, that is to say when the gripper is in its released state in which gas under pressure is injected into the suction cup 10 that it comprises, the presence of said valve 18, associated with the configuration of the pressurized gas supply circuit in the vacuum chamber 11, then leads, by Venturi effect also known per se, to the maintenance of the vacuum in said vacuum chamber. The injection valve 18 is, as mentioned above, a normally open valve, each gripper is, by default, in its product release state, and therefore contributes, with the exception of moments of seizure of a product, the maintenance of said depression. This makes it possible, in particular, to reduce the capacity of the general pumping device 12 and thus to reduce the cost of the installation according to the invention.

It then results from the maintenance, by the Venturi effect, thanks to the non-switched grippers in their gripping state, of the vacuum in the common vacuum chamber 11 of the gripper module, that the leak resulting from an imperfect coincidence of the surface superior product with the suction cup of a gripper of a module will not be sufficient to lead to imperfect seizure or untimely release of the product.

This last point therefore authorizes the establishment, in the vacuum chamber 11 of the module in question, of a low vacuum with respect to the atmospheric pressure, which depression will therefore be all the more easily maintained by the Venturi effect. This also makes it possible to reduce the capacity of the pumping unit used for the preliminary establishment of this depression or the readjustment thereof.

It should also be noted that the grouping of grippers into modules to form the gripper matrix offers here an additional advantage in terms of rationalization and economy of operation of the installation according to the invention.

In fact, the gripper modules are preferably defined according to the shapes and dimensions of the products to be gripped. Thus, by way of nonlimiting example, in the case where the installation is intended, besides the sorting of small products that can be individually grasped by a gripper, sorting products such as bread sticks, the modules of grippers will preferably be defined in such a way that the sum of the gripping surfaces of the grippers of the grippers which constitute them is representative of the area occupied by one of said breadsticks on the primary conveyor, both in its dimensions and in its shape.

It follows that, in certain cases, during the selective entry of the products on the primary conveyor, all the suction cups of some of the modules may not be suitable for the entry of any product according to the criteria defined above relating to at the intersection surface between sucker and upper surface of said products.

The invention then provides for maintaining such a module in a standby state in which the connection between the vacuum chamber 11 of this module and the general pumping device 12 is closed, and in which the connection between the common supply chamber in pressurized gas from this module and the general device for supplying pressurized gas is also closed. This results in an operating economy of the system, the operation of the pumping device and the pressurized gas supply device can then be optimized for the only modules of which some grippers are used for the input of the products to be sorted.

The figure 3 schematically shows in the form of circles the gripping surfaces of the suction cups 10 of a matrix of grippers 1, while it indicates in solid lines the outlines of different products, here products having the elongated shape of bread sticks. On the figure 3 are also shown, in broken lines, the contours of two gripper modules M, respectively designated under the M1 and M2 marks.

According to the example illustrated by this figure, only the grippers such as the entire gripping surface of their suction cup 10 is opposite the upper surface of a product to be gripped are switched in their input state: the suction cups of these grippers are represented by blackened circles on the figure 3 . According to other nonlimiting embodiments, only the grippers such as the intersection of the gripping surface of their suction cup with the upper surface of a product to be gripped represents more than half of said grip surface of said gripping surface. Suction cup 10 can be switched in their input state.

It is also apparent from the observation of figure 3 that if the module designated by the mark M1, a part of the grippers will be activated at the input of the product designated by the reference B1 in the figure, is active during the input operation, the module designated by the reference M2, none of which grippers will be activated for the entry of one of the products designated by the marks B2 or B3 in the figure, will be maintained in the standby state that has been described above.

Once grasped by the gripping die 1, the products are transferred by it to the secondary conveyor C.

According to another of the characteristics of the installation according to the invention, a camera 3, preferably a linear camera, is placed between the primary conveyor A and the secondary conveyor C, on the path of the products grasped by the gripping matrix 1 during their transfer to the secondary conveyor, to capture images of the underside of the products hanging from the grippers of the gripper matrix and transported by the latter to the secondary conveyor C.

The invention provides that the images captured by the camera 3 are processed by appropriate electronic means to deduce a validation information of the individual input of each product by the gripping matrix 1. Concomitantly, information such as shape or color of the underside of the products can also be derived from these images, information on the basis of which, by comparison with a set of previously defined quality criteria, a second attribute of quality can then be automatically assigned to the products examined.

The invention provides that this input validation information, possibly combined with the second quality attribute, is then used to control the distribution of products transported by the gripping matrix. For example, the products transported by this matrix may, depending on the second quality attribute assigned to them, be released above a rejection zone R located in the vicinity of the secondary conveyor, or be released over the Conveyor C on which they can then, based on the input validation information, be counted and then grouped in batches by predefined quantities, for example for packaging before shipment.

The invention thus makes it possible at the same time to limit the counting errors that can result, in particular in the case of elongated products such as baguettes of bread, of an imperfect seizure of these products by the gripping matrix, as well as to realize , together with the control for the counting of these products, a complete quality control of these products, and this partly in masked time.

It allows an increase in production rates, especially as it allows, by the modularity of the elements it implements, the realization of the operations it offers at a high rate.

This aspect is more particularly illustrated by the Figures 2A to 2D which present the various steps of carrying out these operations by means of an installation comprising a primary conveyor A, two secondary conveyors designated by the marks C 'and C ", parallel to the primary conveyor A and symmetrically arranged with respect to the latter, as well as two grip dies, designated by the marks 1 'and 1 "The conveyors C' and C" run in directions parallel to the direction of travel F of the primary conveyor A.

With reference to these figures, the products B to be checked are driven in scrolling on the primary conveyor A, through the first visiometry station 2 in which images of their upper faces are captured, images of which location information is deduced, as well as that, if necessary, a first attribute of quality.

In a first step, these different pieces of information are used to control the gripping, by the gripping matrix 1 ', of a predefined quantity of products B present on the primary conveyor A (see Figure 2A ). During the entire phase of gripping the products, the gripper matrix 1 'advantageously moves parallel to the direction of travel of the primary conveyor, and at the same speed as the latter to accompany the seizure of products and facilitate.

The gripping matrix 1 'to the grippers from which the gripped products B are suspended is then moved in direction towards one of the secondary conveyors (here the conveyor C'), and at the same time, the gripping matrix 1 "is brought above the primary conveyor A to enter a new predetermined quantity of products selectively selected according to the first quality attribute that has been assigned to them ( Figure 2B ). The displacements of the gripping dies 1 'and 1 "are respectively represented by the arrows 100 and 200 on the Figure 2B .

During the transfer of the products transported by the gripping matrix 1 'to the secondary conveyor C', images of the lower face of these products are captured by a camera 3 ', preferably a linear camera, arranged between the primary conveyor A and said secondary conveyor C ', images from which is individually deduced, for each product, validation information of the input by the gripping matrix 1, and possibly a second attribute of quality.

The release and distribution of the products transported by the gripping matrix 1 'is then controlled according to the input validation information as well as, if appropriate, the second quality attribute assigned to them, while the gripping matrix 1 "is controlled moving towards the secondary conveyor C" and the lower face of the the products it carries is examined, during this movement, by a camera 3 ", preferably a linear camera, placed between said secondary conveyor C" and the primary conveyor A ( Figure 2C ). By way of nonlimiting example, the products assigned an attribute of given quality can be released by the gripping matrix 1 'on the secondary conveyor C' to be conveyed to a packaging unit, the products being assigned attributes of different quality being released over a rejection zone R 'located in the vicinity of the secondary conveyor C'. In the delivery of the products released on the secondary conveyor C "to, for example, a packaging unit, the input validation information is then taken into account for the counting of the products for their grouping in batches so to avoid any counting errors resulting, for example, from the premature fallout of a product on the primary conveyor due to a poor gripping by the grippers concerned, the displacements of the gripping matrices 1 'and 1 "respectively to, by for example, the rejection zone R 'and towards the secondary conveyor C "are represented by the arrows 300 and 400 on the Figure 2C .

Once the release of the products grasped by the gripping matrix 1 'has been completed, the latter is moved in order to be placed again above the primary conveyor A and to make a new entry of a predefined quantity of products, while the gripping matrix 1 "realizes the release of the products that it transports according to the second attribute of quality which has been assigned to them in the visiometric station comprising the camera 3" ( 2D figure ). The displacements of the gripping dies 1 'and 1 "are here respectively represented by the arrows 500 and 600 on the 2D figure .

The use of conveyors of the "modular belt conveyor" type finds here an additional advantage, in that it makes it possible to modulate the flow of products arriving in the first visiometric station 2 so as, on the one hand, to adjust it to the movement speeds and gripping rates of 1 'and 1 "gripping dies to avoid clutter primary conveyor A, and, secondly, to allow accumulation, on the primary conveyor A, a sufficient number of products to be grasped by the gripping dies.

It should be noted that a recovery zone and / or rejection R is here placed in the vicinity of the primary conveyor A, downstream thereof with respect to its direction of travel, in order, in particular, to collect products whose grasping by one or the other of the gripping dies 1 'and 1 "was imperfect.

It is clear from the embodiment illustrated by the Figures 2A to 2D that the installation according to the invention makes it possible to carry out a high-speed sorting of the products conveyed by the primary conveyor A, sorting during which control operations are performed in masked time when the products are moved towards one or the other. other secondary conveyors, thus allowing optimization of the speed of the production line. The invention also allows maximum flexibility in the configuration of the conveyors, which allows an optimization of its insertion into the production line. By the implementation of original gripping matrices, it also makes it possible to simplify the management of the gripping and the release of the products, as well as a simplification of the control of the displacements of said gripping matrices. The installation according to the invention is finally of a simple design and low energy consumption, and its insertion into the production line does not induce high additional cost.

The invention can not, however, be limited to the embodiments and means described above, and it extends in particular to all equivalent means and any technically operating combination of such means. In particular, the number of gripping dies and primary and / or secondary conveyors is not limited to those described in the embodiments presented above. In particular, the number of secondary conveyors with respect to the number of primary conveyors will advantageously be determined according to the time required for the mechanical control of the selective entry of the products on the primary conveyor and the transport of said products to said secondary conveyors. These mechanical operations are indeed those which condition, ultimately, the speed of execution of the method according to the invention.

The shape of the suction cups of the grippers, as well as the configuration of the grippers within a module are also likely to vary according to the application and the type of product considered. It should also be noted that the number and type of cameras of the various observation and examination zones given in the foregoing are in no way limiting.

Claims (9)

Apparatus for visiometric control of scrolled products on conveying means on which they are placed, characterized in that it comprises: a first visiometric station (2) comprising means for performing a first visiometric examination of products running on a primary conveyor (A) and associated image processing means to automatically deduce a location information of the present products; on a determined area of said primary conveyor, transfer means which comprise multiple pneumatic gripping devices (P) with automatic individual control, as a function of said location information, in selective input of the products thus located, and which transfer said products from said primary conveyor (A) to a conveyor secondary (C), means (3) for performing a second visiometric examination, relating to the underside of the products during their passage through a transfer zone between said primary conveyor and said secondary conveyor, to individually validate the seizure of the products by said devices pneumatic grip, means for automatically controlling the distribution of products at the output of the secondary conveyor (C) as a function of counting information of said products deduced from said validation information of the input of these products. Installation according to claim 1, characterized in that said first visiometric examination station (2) comprises image acquisition means and associated image processing means programmed to automatically deduce from said images a first attribute quality combined with said location information for controlling the selective entry of products on said primary conveyor (A). Installation according to either of claims 1 or 2, characterized in that said second visiometric examination station comprises image acquisition means and associated image processing means programmed to automatically deduce said images a second quality attribute combined with said validation information of the input of said products to control the distribution of said products on the secondary conveyor (C). Installation according to any one of claims 1 to 3, characterized in that the pneumatic gripping device comprises at least one gripping matrix (1) formed of at least one module (M) grippers (P) each of which comprises a suction cup (10), means for connecting said suction cup to a common vacuum chamber (11) connected to a general vacuum circuit (12), means for connecting said suction cup to a pressurized gas supply circuit ( 13), and a normally open injection valve (18) disposed on said pressurized gas supply circuit, injection valve (18) whose closure controls the switching of the corresponding gripper (P) in its input state. by suction by said suction cup (10), the pressurized gas supply circuit of each of said grippers (P) forming, in said common vacuum chamber (11), a Venturi tube whose suction takes place in said chamber common vacuum. Installation according to any one of claims 1 to 4, characterized in that it comprises selectively switching control means in their gripping state grippers (P), the gripping surface of the suction cup (10) has, with the upper surface of a product to be grasped, an intersection whose surface represents at least half of the gripping surface of said suction cup (10). A method of sorting scrolling products, in particular industrial bakery products, in which: - Locating, by a first visiometric examination, the goods moving on a primary conveyor (A) to achieve the selective seizure a predefined number of them by a set of pneumatic grippers (P) and their transport to a secondary conveyor (C), during the transport to said secondary conveyor, a visiometric examination of the underside of the seized products is performed in order to deduce, for each of them, validation information of its gripping by pneumatic grippers (P), - From this validation information is deduced a product counting information used for the distribution of the latter on said secondary conveyor (C). Method according to claim 6, characterized in that the selective entry of the products on the primary conveyor (A) is performed according to the combination of said location information and a first quality attribute assigned to each of the products in its face. superior and deduces images captured during said first visiometric examination. Method according to either of Claims 6 or 7, characterized in that the distribution of the products on the secondary conveyor (C) is performed as a function of the combination of the validation information of their input and of a second quality attribute assigned to each of said products and deduces images captured during said second visiometric examination. Process according to any one of Claims 6 to 8, characterized in that the said pneumatic grippers (P) are individually controlled to carry out the gripping of the said products as soon as the intersection of the surface of a suction cup (10) they comprise to achieve the suction of a product with the upper surface of the part of the product to be grasped in front of which said gripper is placed is greater than or equal to half of the gripping surface of said suction cup (10).

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