SYSTEM OR MACHINE FOR SORTING ITEMS WITH AN AIR CONTROL DEVICE

Abstract

A system (1) for sorting items (2), comprising, advantageously mounted in a housing (1'), a sorter (3) with planar geometry and an air control system (4) that controls the air circulation in the system (1), wherein the sorter (3) comprises at least the following: - a conveyor (5) with a continuous belt (5') on which the items (2) to be sorted are arranged in a simple position, - a detection device (6) configured to inspect the items (2) circulating on the conveyor (5) and, after analysis, to classify them into at least two categories, - an air jet ejection device (7) located at the outlet end (5") of the conveyor (5) and configured to selectively eject upwards the items (2) that are detected as belonging to at least one of the classification categories and fall from this outlet end (5"), - at least one partition (8),which is arranged at a distance from the discharge end (5") of the conveyor (5) and is configured to separate at least one stream (FOCL) of free-falling items (2) and one stream (FOE) of ejected items (2), wherein the air control system (4) comprises at least the following: - an enclosure structure (9) extending above the conveyor (5) over a longitudinal portion of the latter and forming a guide tunnel (9') with it, into which a laminar airflow (FAL) is introduced, circulating at substantially the same speed as the items (2) to be sorted; - an outlet box (10), which may optionally be part of or mounted in the housing (1') and which interacts with the partition or partitions (8) to form a chamber (11) for receiving the non-ejected items (2) and at least one chamber (11') for receiving the ejected items (2), wherein these chambers (11,11') respective outlets (12) for removing the categorized items (2) that have fallen in, wherein the system (1) is characterized in that the outlet box (10) is subjected to an air extraction system in order to discharge the excess air in the system (1) to the outside, essentially without disturbing the flows of the items (2) to be sorted or already sorted, and that it comprises two independent air circulation devices (13, 14), for example with turbines, one (13) of which ensures the introduction of outside air to generate the laminar airflow (FAL) and the other (14) of which ensures the extraction and discharge of the excess air to the outside of the system (1) at the outlet box (10),and that the device (14) for air extraction and discharge is regulated or controlled at least depending on the surface area and quantity of the sorted items (2) as well as on the air passage possibilities at the fume hoods (12) for discharge.