FR3139328A1 - Universal recovery system for incorrectly positioned items on an automatic sorter - Google Patents

Abstract

TITLE: Universal recovery system for incorrectly positioned items on an automatic sorter System (1) for universal recovery of items (6) incorrectly positioned on an automated sorter (100) and which cannot be ejected normally by a sorting unit an outlet from the sorter, the automated sorter comprising a conveyor (200) forming a circulation path composed of conveyors (20) connected to each other in an articulated manner to form a train which circulates in a loop, each conveyor comprising a sorting unit ( 2), said recovery system comprising: means (7) for detecting incorrectly positioned articles capable of differentiating an article which can be ejected normally by a sorting unit towards an outlet (40) of the sorter from a poorly positioned article which cannot be ejected normally by a sorting unit towards an outlet of the sorter, means (9) for ejecting the sorting unit by blowing articles that are incorrectly positioned and cannot be ejected normally, means of recovery ( 5) articles ejected by gravity blowing into a recovery structure, the system being furthermore capable of being installed either on a straight section or a curved section of the circulation path of an existing conveyor. Figure for abstract: Figure 6

Description

Universal recovery system for incorrectly positioned items on an automatic sorter Technical field of the invention

The invention relates to an automatic item retrieval system. It concerns more particularly a system for recovering poorly positioned items intended to be installed on automated sorters.

Technical problems addressed by the invention

An automated sorter is an industrial installation used to transport articles from one or more loading zones to unloading exits chosen according to the predefined final destination of the articles, with each exit corresponding to a destination.

For this, the sorter comprises a conveyor forming a traffic lane composed of conveyors connected to each other in an articulated manner to form a train which circulates in a loop, each conveyor comprising a sorting unit.

Items are automatically transported to the conveyor via injectors making up a loading zone. These injectors retrieve information from the free sorting units upstream, in order to reserve the location and load the item in question when the sorting unit passes in front of the injector.

The identification of free sorting units is carried out by a control zone located on the sorter before each loading zone.

The articles are studied upstream of the loading zone. They are defined as treatable by the sorter when their characteristics respect a rule including minimum and maximum accepted characteristics, for example according to the length, width, height and weight of the article. If they are defined as unprocessable, the items are transferred to a manual processing station.

Once loaded on a free sorting unit, the item is then transported by the transporter to the chosen exit before being unloaded (ejected) towards this exit by activation of the sorting unit. These exits can be pick-up areas or shipping areas.

The sorting unit mounted on the conveyor is for example a cross belt, called in English crossbelt. An item is placed on the cross belt at a loading station, which remains stationary as the conveyor moves to the destination exit. It is then set in motion by a motor, which causes the item to be ejected perpendicularly, or at a substantially acute angle, to the direction of travel of the conveyor.

Each sorting unit includes a fixed blade to ensure continuity of the plane formed by the upper part of the crossed strips, particularly in bends in the traffic lane. On a straight section of the travel lane, more of a sorting unit's blade is in a gap in the neighboring conveyor, below the top of its cross belt, with little of the blade's surface remaining visible. In bends, the blade becomes more visible on the side where the space between the sorting units is increased, that is to say, the side furthest from the center of rotation of the conveyors.

The blade can help carry an item that is poorly positioned on a sorting unit and which extends beyond the crossed belt by resting partly on the blade of the sorting unit on which it is placed or on that of the neighboring sorting unit . It can also carry an item positioned by mistake between two sorting units, or having slipped between two sorting units during the movement of the carrier.

Automated sorters are required to handle a wide range of items, for example with weights of up to 50 kg, and varied shapes or volumes with conveyor movement speeds of up to 3 m/s. The articles are for example wrapped or unwrapped objects, letters, packages, or empty plastic bins or containing one or more objects.

Certain articles meeting the conditions required to be loaded on the automated sorter are unstable, for example due to their floating shapes in correlation with the conveying speed. This sometimes causes the sorter to malfunction, for example when loading items into the sorting units or when moving them to the destination exit, particularly on bends, when the item moves to a position where it is incorrectly positioned, for example between two sorting units. This anomaly prevents the operation of one or two sorting units, depending on the position of the item, in their unloading function towards the exits. The item remains stuck on the conveyor and rotates in a loop on the traffic lane, which has the effect of obscuring one or two sorting units.

Sorting units inhibited by the presence of a blocked item reduce the number of free slots for the injection of items via loading zones, leading to a reduction in sorter productivity in processing items. A maintenance agent must intervene periodically to extract these blocked items, constituting a waste of time.

The object of the invention is to remedy all of these drawbacks.

• Un moyen de détection d’articles mal positionnés apte à différencier un article pouvant être éjecté normalement par une unité de tri vers une sortie du trieur d’un article mal positionné qui ne peut pas être éjecté normalement par une unité de tri vers une sortie du trieur,
• Un moyen d’éjection de l’unité de tri par soufflage des articles mal positionnés et ne pouvant pas être éjectés normalement,
• Un moyen de récupération des articles éjectés par soufflage par gravité dans une structure de récupération.

According to a first aspect of the invention, a universal recovery system is proposed for articles incorrectly positioned on an automated sorter and which cannot be ejected normally by a sorting unit towards an outlet of the sorter, the automated sorter comprising a conveyor forming a traffic lane composed of conveyors connected to each other in an articulated manner to form a train which circulates in a loop, each conveyor comprising a sorting unit, said recovery system comprising:

• A means for detecting poorly positioned articles capable of differentiating an article which can be ejected normally by a sorting unit towards an outlet of the sorter from a poorly positioned article which cannot be ejected normally by a sorting unit towards an outlet of the sorter sorter,
• A means for ejecting from the sorting unit by blowing items that are poorly positioned and cannot be ejected normally,
• A means of recovering ejected articles by gravity blowing into a recovery structure.

The system is also capable of being installed either on a straight section or a curved section of the circulation path of an existing conveyor.

Depending on its position, an item may be incorrectly positioned while still being able to be ejected normally by the sorting unit towards a sorter exit. It is thus advantageous to eject the article towards its destination exit from the sorter rather than towards the recovery structure according to the invention. The detection system according to the invention is thus capable of distinguishing poorly positioned articles which cannot be ejected normally by a sorting unit towards an exit of the sorter so as not to activate ejection by blowing towards the recovery structure only for items that cannot be ejected towards the sorter exits.

The device according to the invention is capable of recovering unstable articles moving on the sorter and the latter is advantageously kept in operation during the article recovery operation.

The article detection system includes several control functions avoiding disrupting the processing of articles correctly conveyed to the sorting units adjacent to the one on which a poorly positioned article to be ejected is placed, or to those between which this article is placed .

The use of blowing to eject the poorly positioned article has several advantages, in particular being simple to implement and being effective whatever the shape of the article.

Blowing is carried out by one or more blowing ramps placed on one side of the conveyor. The pressure exerted by the blow on the poorly positioned item causes it to slide on the blade and/or the cross belt of the sorting unit until it leaves the conveyor. It then falls by gravity into a recovery structure located on the other side of the conveyor.

Blowing is controlled and subject to approval by the detection means. Several variables are taken into account in order to correlate the blowing phase and the speed of the sorter, while avoiding the impact of the ejection function on other neighboring items.

The recovery structure is defined and grants the ejection function, allowing the article to be received into a container placed at the recovery structure, without generating multiple risks. This recovery structure can be adjusted in shape and dimensions on demand and according to the sorter's environment.

The recovery system can be installed either on a straight section or a curved section of the travel lane of a conveyor, it is suitable for any type of conveyor, whatever the shape of the travel lane at the location where it is advantageous to position it for optimal operation, making it universal.

The recovery system according to the invention comprises equipment arranged on either side of the conveyor which is fixed on dedicated supporting structures, distinct from the conveyor.

The recovery system can thus be installed on an existing sorter, without the need to modify it. It is thus possible to put it in place quickly, limiting the sorter downtime necessary for this operation.

The recovery system according to the invention comprises equipment fixed to the supporting structures by means of joints or pivot plates.

The use of articulation or pivot plates makes it possible to orient the equipment of the recovery system in relation to the conveyor at an appropriate angle for optimal operation of the system, whether it is installed on a straight section or a curved section of the conveyor .

The system for detecting poorly positioned articles includes, for example, a set of photoelectric cells.

On a straight section, these photoelectric cells are arranged substantially at 90 degrees relative to the direction of travel of the conveyor, while on a curved section, the cells are arranged at a different angle which is a function in particular of the radius of curvature of the section of conveyor.

• Un meilleur taux de disponibilité des unités de tri,
• D’éviter un impact du système de récupération sur les articles correctement acheminés et destinés aux diverses zones de déchargement.

The recovery system according to the invention is defined to be installed in a location located between exits and the control zone which precedes them, allowing:

• A better availability rate of sorting units,
• To avoid an impact of the recovery system on items correctly transported and intended for the various unloading areas.

The recovery system further comprises an autonomous unit for monitoring and controlling constituent elements of said system. This unit can thus ensure the operation of the recovery system without needing to be connected to the sorter control and control system. It can be added easily and quickly to all types of existing sorter, without it being necessary to modify it. The shutdown for the commissioning of the system will be of shorter duration than that which would be necessary if the recovery system had to be controlled by the control and command system of the sorter. It is therefore not necessary to make any modifications to the sorter's control and control system. As an alternative embodiment, the control and command unit of the recovery system can nevertheless be connected to the control and command system of the automated sorter.

• une étape de détection d’un article mal positionné qui ne peut pas être éjecté normalement par une unité de tri vers une sortie du trieur,
• une étape d’éjection par soufflage dudit article,
• une étape de récupération de l’article éjecté par soufflage dans une structure de récupération.

According to a second aspect of the invention, a method is proposed for universal recovery of articles incorrectly positioned on an automated sorter and which cannot be ejected normally by a sorting unit towards an exit of the sorter by means of a system of recovery as described previously, the process comprising:

• a step of detecting a poorly positioned item which cannot be ejected normally by a sorting unit towards an exit of the sorter,
• a step of ejecting said article by blowing,
• a step of recovering the article ejected by blowing into a recovery structure.

The recovery system monitoring and control system ensures control of the sorter's cadence in order to activate the recovery system only during normal sorter operating conditions, so as not to impact the starting or stopping of the sorter. Thus, according to the invention, the ejection by blowing of an article is only authorized if the speed of the conveyor is greater than a defined speed. This precaution also makes it possible to optimize the safety of goods and people, by avoiding ejecting articles from the recovery structure.

Brief description of the figures

Other characteristics and advantages of the invention will appear during reading of the detailed description which follows, for the understanding of which we will refer to the appended drawings in which:

. is a partial schematic view, in plan and top view, of an automated sorter comprising a recovery system arranged on a straight section of the sorter, according to an exemplary embodiment of the invention,

. is an enlarged view of the sorter portion of the at a curved section of the conveyor,

. is an enlarged view of the sorter section of the at the level of the recovery system, with a first example of positioning a package,

. is a view similar to the for a second example of package positioning,

. is a view similar to the for a third example of positioning a package, and

. is a view similar to the showing the trajectory of the package as it is ejected by the recovery system.

Detailed description of the invention according to an exemplary embodiment

We can see on the , a schematic and partial overview of an automated sorter 100, seen from above. It includes a conveyor 200 forming a traffic lane in the direction indicated by arrow 3.

The conveyor comprises a set of conveyors 20 connected to each other, five units being represented at a curved section 23 of the traffic lane.

Each conveyor comprises a sorting unit 2 with a crossed belt, which comprises a fixed blade 21 making it possible to ensure continuity of the plane formed by the upper part of the crossed belts.

The sorter comprises five loading units 30 and a plurality of outlets 40. Between the last outlet 41, in the direction of movement of the conveyor, and the first loading unit 31 is arranged a control zone 50.

Between the last exit 41 and the control zone 50 is placed a system 1 for recovering poorly positioned articles according to an exemplary embodiment of the invention. For this, the system is placed in a straight section of the traffic lane, just before a curved section.

There is an enlargement of the curved section 23 of the taxiway of the . We can see in this figure that the blades 21 of the sorting units 2 are barely visible on the straight sections, being then mainly covered by the crossed strip of the neighboring sorting unit, while they are much more visible on the parts curved.

We can see on the , the portion of the conveyor 200 of the automated sorter of the on which the system 1 for recovering incorrectly positioned articles is installed according to this exemplary embodiment of the invention.

Six sorting units 2 are represented on this portion of the conveyor. The sorting units are moved from right to left, according to arrow 3.

System 1 for recovering poorly positioned items includes equipment placed on either side of the conveyor.

In the direction of movement of the conveyor, it firstly comprises a system 4 for detecting the articles 6 present on the sorting units. This comprises three successive pairs of photoelectric cells, each pair comprising a transmitter E1, E2, E3, placed on one side of the conveyor and a receiver R1, R2, R3 placed on the other side of the conveyor. The central pair E2/R2 of cells makes it possible to detect the presence of articles positioned between two sorting units. The detection system further comprises means 7 for detecting the position of the sorting units and the rate of the sorter.

The presence and location of the articles is determined by the breakage of the light beam between a pair of cells by an article during its passage, this information being correlated to the position of the sorting units determined from the means 7 for detecting the position sorting units.

As shown in , the article detection system identifies an article 6 simultaneously obscuring the pairs of photoelectric cells E2/R2 and E3/R3. Taking into account the position of the sorting units determined from the means 7, the control and control unit 8 of the recovery system determines that the product is positioned on a first sorting unit 2a but that it slightly overflows onto a second adjacent sorting unit 2b. For this example, the recovery system does not carry out the function of ejecting the article considering that it can be ejected normally by the sorting unit 2a towards its destination exit during its second passage towards the unloading outlets 40. If the unloading of the package should fail, the item ejection function can be activated during its next passage through the recovery system if it has retained the same position on the sorting units or if its new position makes it desirable his ejection.

We can see on the , the conveyor portion of the with this time a first article 6a positioned between two adjacent sorting units 2a and 2b and a second article 6b positioned on the sorting unit 2b. For this example, the recovery system does not carry out the ejection function so as not to disrupt the unloading function of the article 6b by the sorting unit 2b. This will then be unloaded by the sorting unit during its second pass through the unloading zone. The article 6a positioned between the two sorting units 2a and 2b will be ejected by the recovery system during its next passage.

We can see on the , the conveyor portion of the with this time an article 6 positioned between two adjacent sorting units 2a and 2b. The presence of this article is indicated by the pair E2/R2 of photoelectric cells taking into account the position of the sorting units determined from the means 7. The two other pairs E1/R1 and E3/R3 of photoelectric cells indicate that there is no other article on sorting units 2a, 2B. In this situation, all conditions are met to eject the incorrectly positioned item without impacting the operation of the automated sorter and neighboring items located on other sorting units. The unit 8 for monitoring and controlling the elements of the device carries out the function of ejecting the article 6 by activating, when the time comes, the means for ejecting the article towards a receiving structure 5 by means of pneumatic blowing produced by two blowing ramps 9.

As shown in , The blowing of the blowing ramps is activated when the article 6 arrives in the vicinity of these and it is interrupted after the ejection of the article, taking into account the speed of movement of the conveyor.

The recovery system also includes a function for reporting its operating status. For example, it takes the form of a light terminal 13 which indicates different states of the system, depending on its color. Thus the terminal displays a fixed green light in normal operation, excluding ejection of an item, it displays a fixed orange light during the ejection phases of an item and it displays an intermittent red light in the event of a system failure.

Advantageously according to the invention, on either side of the conveyor, the equipment of the recovery system is fixed on structures 10,11,12 in dedicated aluminum profile, distinct from the conveyor, without mechanical connection with it. These structures include joints and pivot plates to adapt to the shape of the conveyor to the location where the recovery system must be installed and to orient the equipment that requires it. Thus, the system can easily be positioned at a straight section or a curved section of the conveyor.

According to another alternative embodiment of the invention, the equipment of the recovery system is fixed on dedicated aluminum profile structures 10,11,12 added to the conveyor, with a mechanical connection thereto. For example, they are installed on the sides of the fixed structure of the conveyor by means of pivoting fixing plates making it possible to adapt to the shape of the structure of the conveyor, depending on whether the system is positioned at the level of a straight section or a curved section of the conveyor.

For example, the photocell mounting brackets are adjustable to adapt to the straight or curved shape of the conveyor section where the recovery system is installed. In the straight zone, the cell bundles are parallel to each other and perpendicular to the movement of the conveyor. In a curved zone, the beams are not perpendicular to each other due to the curvature of the conveyor. Thus, the cell fixing supports are multi-directionally adjustable to allow easy positioning of the cells, whatever the shape of the conveyor.

The blower manifolds are fixed to the compressed air supply network using a wall-pass fitting fixed to a machined plate. They are also each equipped with a ball joint which, depending on the linear or curved zone of the conveyor, allows them to be oriented to target the impact zone of the item to be ejected.

Claims (6)

System (1) for universal recovery of articles (6) incorrectly positioned on an automated sorter (100) and which cannot be ejected normally by a sorting unit (2) towards an exit from the sorter, the automated sorter comprising a conveyor ( 200) forming a traffic lane composed of conveyors (20) connected to each other in an articulated manner to form a train which circulates in a loop, each conveyor comprising a sorting unit (2), said recovery system comprising:

• means (7) for detecting incorrectly positioned articles capable of differentiating an article which can be ejected normally by a sorting unit towards an outlet (40) of the sorter from a poorly positioned article which cannot be ejected normally by a unit sorting to a sorter exit,
• means for ejecting (9) from the blow sorting unit items that are poorly positioned and cannot be ejected normally,
• a means (5) for recovering articles ejected by gravity blowing into a recovery structure,

the system being furthermore capable of being installed either on a straight section or a curved section (23) of the circulation path of an existing conveyor. System according to the preceding claim, characterized in that it comprises equipment arranged on either side of the conveyor which is fixed on dedicated supporting structures (10,11,12) distinct from the conveyor. System according to the preceding claim, characterized in that equipment is fixed to the supporting structures by means of joints or pivot plates. System according to one of the preceding claims, characterized in that it comprises an autonomous control unit (8) and command of constituent elements of said system. Method for universal recovery of articles (6) incorrectly positioned on an automated sorter (100) and which cannot be ejected normally by a sorting unit towards an exit (40) of the sorter by means of a system according to one of the preceding claims, characterized in that it comprises:

• a step of detecting a poorly positioned article which cannot be ejected normally by a sorting unit towards an exit of the sorter,
• a step of ejecting said article by blowing,
• a step of recovering the article ejected by blowing into a recovery structure.

Method according to the preceding claim, characterized in that the ejection by blowing of an article is only authorized if the speed of the conveyor is greater than a defined speed.