Sorting machine

1. A sorting machine comprising:

a plurality of carriages ( 2 ), each carriage ( 2 ) comprising a loading-unloading device ( 3 ) which can be selectively activated for loading-unloading an object (O) from the carriage ( 2 ) and an electronic unit ( 4 ) configured to receive and analyse a loading-unloading signal and actuate the loading-unloading device ( 3 ) as a function of an operating mode, selected from a plurality of operating modes and uniquely associated with the loading-unloading signal;

a plurality of loading stations ( 9 ) and a plurality of unloading stations ( 10 ) positioned along a sorting direction (X) comprising respective actuating units ( 11 ) configured to generate the loading-unloading signal;

characterised in that each carriage ( 2 ) comprises a permanent magnet ( 4 c ) which generates a stationary magnetic field and each actuating unit ( 11 ) comprises a Hall effect transducer ( 12 ) configured to detect the presence of the stationary magnetic field generated by the permanent magnet ( 4 c ), wherein the permanent magnet ( 4 c ) remains stationary with respect to the carriage ( 2 ) when the loading-unloading device ( 3 ) is activated for loading or unloading an object (O) to or from the carriage ( 2 ).

2. The machine according to claim 1 , wherein the permanent magnet ( 4 c ) is positioned in a front portion of the carriage ( 2 ) relative to a feed direction of the carriage ( 2 ) along the sorting direction (X).

3. The sorting machine according to claim 2 , wherein each actuating unit ( 11 ) of each loading station ( 9 ) or unloading station ( 10 ) comprises a respective inductor ( 11 a ) designed to generate a magnetic field with a variable frequency which is detected by the electronic unit ( 4 ) on a respective carriage ( 2 ).

4. The sorting machine according to claim 1 , wherein each actuating unit ( 11 ) is configured for transmitting the loading-unloading signal when the Hall effect transducer ( 12 ) detects the magnetic field generated by the permanent magnet ( 4 c ) of the carriage ( 2 ) to which the load-unloading signal is directed.

5. The sorting machine according to claim 1 , wherein each actuating unit ( 11 ) is configured for transmitting the loading-unloading signal when the Hall effect transducer ( 12 ) detects the maximum intensity of the magnetic field generated by the permanent magnet ( 4 c ) of the carriage ( 2 ) to which the loading-unloading signal is directed, that is, when the distance between the Hall effect transducer ( 12 ) and the permanent magnet ( 4 c ) is at its minimum.

6. The sorting machine according to claim 1 , wherein each actuating unit ( 11 ) is configured for transmitting the loading-unloading signal after a waiting time of between 0 seconds and 1 second from when the Hall effect transducer ( 12 ) detects the magnetic field generated by the permanent magnet ( 4 c ) of the carriage ( 2 ) to which the loading-unloading signal is directed.

7. The sorting machine according to claim 1 , wherein each Hall effect transducer ( 12 ) has a nominal radius of between 30 mm and 40 mm.

8. The sorting machine according to claim 1 , wherein a single carriage ( 2 ) of the plurality of carriages ( 2 ), defined as the first carriage ( 2 a ), comprises a main permanent magnet ( 4 d ) which generates a stationary magnetic field of intensity different to the intensity of the magnetic field generated by the permanent magnet ( 4 c ) of each other carriage ( 2 ).

9. The sorting machine according to claim 8 , wherein the main permanent magnet ( 4 d ) is made with at least one feature which is different from each other permanent magnet ( 4 c ), the at least one feature being selected among: shape of the main permanent magnet ( 4 d ), size of the main permanent magnet ( 4 d ), material from which the main permanent magnet ( 4 d ) is made.

10. The sorting machine according to claim 1 , wherein the loading-unloading signal is a digital signal.

11. The sorting machine according to claim 10 , wherein the digital signal comprises a string of at least one bit.