The present invention relates to the technical field of plants for storing/sorting objects.

In particular, the present invention relates to a method for managing automated guided vehicles (or “AGV”), used in handling goods inside warehouses of forwarding companies, or e-commerce, airports, etc .... Currently, when they are used in the sector of sorting goods to be dispatched, automated guided vehicles are affected by drawbacks that make the automated guided vehicles less efficient than necessary in the sector. In fact, the AGVs are powered by electric batteries that are able to ensure only a limited number of continuous and autonomous hours of work.

Once this battery is near to being flat, the vehicle has to go to an appropriate charging station and remain inactive and unusable for all the time required to recharge or the flat battery to be replaced. Further, the batteries used to power the vehicles are subject to wear and have a limited working life that makes it necessary to replace the batteries, requiring a dedicated procedure to be followed and time to be invested by an operator who deals operationally with replacement thereof.

In this context, the technical task at the basis of the present invention is to propose a method for managing automated guided vehicles which overcomes the aforementioned drawbacks of the prior art.

This technical task is obtained by the method and by the plant in accordance with the attached claims.

Further characteristics and advantages of the present invention will more fully emerge from the indicative and thus non-limiting description of a preferred but not exclusive embodiment of a method for managing automated guided vehicles, as illustrated in the accompanying drawings, in which:

-figure 1 is a plan view of a plant according to the present invention; - figure 2 shows in greater detail a portion of the plant of figure 1.

In the appended figures, the numerical reference 1 indicates in general a sorting plant, identified hereinafter in the present description simply as the plant 1.

The plant 1 comprises at least one automated guided vehicle “V” that is moveable along a sorting path “P” extending inside the plant 1.

In detail, the vehicle “V” comprises a loading-unloading device, a motor means, a battery and a control unit.

The loading-unloading device is selectively actuatable to load an object onto-unload an object from the vehicle “V”.

In accordance with one preferred embodiment, the loading-unloading device is made in the form of a conveyor belt oriented in such a manner as to define in a loading-unloading direction perpendicular to a frontal direction of advancement of the vehicle “V” (of “side-belt” type).

The vehicle is provided with a motor means that can be made by a skeleton used to support the structure of the vehicle “V”, at least three wheels, at least one of which is motor-driven and thus adapted to generate the movement of the vehicle “V”.

The motor is of electric type and is supplied by at least one battery, for example formed by a plurality of cells.

Clearly, the battery accumulates a charge that is used to permit the vehicle “V” both to move along the sorting path “P” and to actuate the loading unloading device to receive and deliver the articles to be shifted.

The control unit is configured to monitor battery status, for example by means of transducers (current, voltage, temperature meters) and can communicate externally all the information obtained (battery voltage, temperature, loading-unloading currents in real time, loading level).

This monitoring enables for example situations of voltage unbalance, overtemperature or overcurrent to be avoided that may damage the battery irreversibly and important information to be obtained on battery integrity. The plant further comprises a plurality of loading stations 2 or unloading stations 3 arranged along the sorting path “P”.

In particular, the plant comprises at least one loading station 2 and at least one unloading station 3.

The term loading station 2 means a point of collection of objects to be sorted that arrive from processes or further plants arranged upstream of the plant 1.

The term unloading station 3 means a point of collection of sorted objects to be transferred to processes or further plants arranged downstream of the plant 1.

Preferably, the sorting path “P” is defined by a closed loop that extends between the loading stations 2 and the unloading stations 4, such that the vehicle “V” can pick up objects from the former and transfer the objects to the latter, and then return to the starting point.

The plant further comprises at least one loading station 4 arranged along the sorting path “P”.

The charging station 4 is configured to charge partially a battery of the at least one vehicle when this vehicle transits at the station.

In other words, the charging station 4 is arranged in a point of the sorting path “P” so that the vehicle “V” transits during its travel between the various loading stations 2 and unloading stations 3 and, whenever the vehicle “V” transits there, the charging station 4 supplies electric power that is such as to charge the battery thereof partially, or up to a fraction of a maximum charge level of the battery.

To be precise, the charging station 4 is configured to charge the battery of the vehicle “V” up to a charging level comprised between 50% and 60%, preferably equal to 55% of the maximum charging level of the battery.

In accordance with a further aspect of the present invention, the charging station 4 is configured to monitor a charge level of the battery of the vehicle and to charge the battery if the monitored charge level is below a value comprised between 40% and 50%, preferably equal to 45%, of the maximum charge level of the battery.

In particular, the charging station 4 is configured to communicate with the control unit of the at least one vehicle “V”, so as to receive therefrom in real time all the information on the battery charge level.

In this manner, the charging station 4 can monitor and regulate the necessary electric parameters (charge at constant voltage or constant current) to charge the battery within the charge levels defined above. Advantageously, these charging stations 4 enable the time to be reduced that is necessary to charge and the working life of the battery to be prolonged, because the battery does not have to suffer continuously large fluctuations in the overall charging level thereof.

Preferably, the plant 1 comprises a plurality of charging stations 4 arranged along the sorting path “P”, so as to ensure the possibility of loading the battery of the vehicle “V” whenever it is necessary, regardless of where the vehicle “V” is located.

In particular, the charging stations 4 can be arranged immediately of one or more loading stations 2 and/or of one or more unloading stations 3.

In fact, the vehicle “V” when moving along the sorting path “P will inevitably have to move from the loading stations 2 or unloading station 3 and accordingly by placing the charging stations 4 immediately upstream thereof it is possible to ensure that the vehicle “V” will traverse the charging stations 4 cyclically.

This solution is particularly advantageous in plants in which the number of loading stations 2 and unloading stations 3 requires a complex sorting path “P” to be devised and which has one or more branches in which the vehicle “V” could follow different branches to reach the loading stations 2 and unloading stations 3.

Structurally, the charging station 4 comprises at least one conductive surface that is adapted to deliver electric power and the vehicle “V” comprises at least one connector configured to slidingly engage the conductive surface, connecting the conductive surface electrically to the battery.

In other words, the electric connector acts as a link between the battery and a source of electric power supplied by the conductive surface of the charging station 4.

In this manner, it is possible to charge the battery of the vehicle “V” whilst the latter moves along the sorting path “P” at the charging station 4. Preferably, the electric connector is movable between an operating configuration, wherein it engages the conductive surface, coming into contact therewith, and a non-operating configuration in which the electric connector does not engage any further element or surface of the plant 1.

In other words, when placed in a non-operating condition, the electric connector is not only not engaged with the conductive surface but does not engage simultaneously any other surface or element present inside the plant 1 and in particular no surface or element arranged along the sorting path “P”.

By way of example, the transition between the operating configuration and the non-operating condition can be obtained by drive means of magnetic type that in the presence of the conductive surface generate a force of attraction that pushes the connector against the conductive surface. Preferably, the conductive surface is made of metal material, even more preferably, the conductive surface is made of galvanized steel.

In accordance with a preferred embodiment shown in the attached figures, the charging station 4 comprises two conductive surfaces, preferably two conductive strips 4a, adapted to deliver electric power and the vehicle “V” comprises two connectors configured to slidingly engage respective conductive strips 4a.

In this manner, it is easier to ensure the connection of the battery with different potentials.

In particular, a first electric connector will engage a conductive strip 4a placed at a first potential (for example a nil potential), whereas a second electric connector will engage a second conductive strip placed at a second potential.

In order to ensure the correct electrical connection between the battery and the conductive surface when the vehicle “V” transits at the charging station 4, it is possible to use a greater number of electrical connectors, the arrangement of which can be varied as a function of the structural features of the sorting path “P” or of the conductive surface, especially with respect to the geometry thereof, in order to ensure at each moment the correct supply to the battery.

The plant can also comprise a plurality of markers 5 arranged along the sorting path “P”, in particular at the charging station 4, which are suitable for supplying to the vehicle “V” a spatial indication representing the positioning thereof along the sorting path “P”.

Preferably, the markers 5 are made by a one-dimensional or two- dimensional barcode applied to a floor of the premises in which the plant 1 is located.

Advantageously, the plant 1 disclosed here overcomes the drawbacks of the prior art by providing a structure that enables the automated guided vehicles "V" to be operated for long periods of time, also extending the useful life of the batteries thereof.

Another object of the present invention is a method for managing automated guided vehicles "V" in a sorting plant 1 , preferably a plant 1 having one or more of the features disclosed above.

The method is applied by moving at least one automated guided vehicle “V” along a sorting path “P” extending inside the sorting plant 1.

Whilst the vehicle “V” is located along the sorting path “P”, preferably whilst the vehicle “V” is moving along the sorting path “P”, the battery of the vehicle “V” is recharged.

In particular, the battery is so charged as to be partially charged, or as already indicated, in such a manner as to be recharged until a level is reached that is equal to a fraction of a maximum possible charge level; in detail, this charge level is comprised between 50% and 60%, preferably equal to 55%, of the maximum charge level thereof.

In accordance with a further aspect of the present invention, the charging step is performed by recharging the battery whenever the charge level of said battery is below a value comprised between 40% and 50%, preferably equal to 45%, of the maximum charge level thereof.

In particular, the charging step is performed so as to maintain the battery charge level in a range comprised between 45% and 55% of the maximum charge level thereof along the entire sorting path “P”.

In this manner, it is possible to use the battery far from maximum loading and maximum unloading conditions (100% - 0%), performing frequent loading/unloading cycles but at low depth, which enable the charging level of the battery to be maintained at around 50% of the maximum value thereof, maximizing the working life thereof.

Preferably, the charging step is performed when the vehicle “V” transits in a portion of the sorting path upstream of at least one loading station 2 or unloading station 3 of the plant 1 , preferably when the vehicle “V” transits upstream of each loading station 2 or unloading station 3.

Operationally, the vehicle “V” moves along the sorting path “P” in accordance with the following work cycle:

- the vehicle “V” at a loading station 2 receives an object to be sorted;

- the vehicle “V” conveys the object as far as an unloading station 3 following the sorting path “P”;

- the vehicle “V” at an unloading station 3 gives to the unloading station 3 the object that it is conveying;

- the vehicle “V” goes again to a loading station 2 (not necessarily the same as the preceding point if several loading stations 2 are present) to receive a further object to be sorted.

Accordingly, the vehicle “V” moves along the sorting path “P” between a loading station 2 and an unloading station 3, then is charged upstream of a loading station 2 or unloading station 3, ensures that the battery is charged at least once every work cycle when the vehicle “V” is transiting between the two.

The charging step can be further performed when the vehicle “V” is at a loading or unloading station of the sorting plant.

In other words, the charging step can be performed whilst the vehicle “V” is receiving an object to be sorted from the loading station 2 and/or when it is giving the object to the unloading station 3.

It is pointed out that the charging step can be performed according to any combination of the situations outlined above, i.e. the charging step can be performed when the vehicle “V” is located at the loading station 2 and/or when the vehicle “V” is moving towards the unloading station 3 and/or when the vehicle “V” is located at the unloading station 3 and/or when the vehicle “V” is moving towards the loading station 2.

Advantageously, the present invention reaches the set objects, overcoming the drawbacks decried in the prior art, providing a method for managing automated guided vehicles "V" inside a sorting plant 1 that optimizes the working life of the batteries of the vehicles “V” and the charging processes thereof, improving in this manner the overall efficiency of the plant 1.