Apparatus for working on metal containers

1. An apparatus ( 10 ) for working on metal containers especially suited for high speed machines intended for performing a sequence of operations on the metal containers, said apparatus comprising a chain including a plurality of successively linked elements ( 12 ) cooperating in simultaneously transporting and processing the metal containers wherein each element ( 12 ) includes an annular central element ( 12 ′) suitable for receiving an interface element ( 16 ) that receives a metal container ( 18 ), said central element ( 12 ′) having oppositely disposed a male shaped link expansion ( 14 ) and a female shaped link ( 14 ′), said shaped link expansions having a toroidal type coupling and having a through hole orthogonal to the chain path, said male shaped link expansion ( 14 ) being annular and including at least one anti-friction element ( 17 ) coaxial to said through hole of said male shaped link expansion ( 14 ).

2. The apparatus according to claim 1 , wherein the toroidal coupling between the contiguous elements ( 12 ) comprises a pin ( 22 ) inserted coaxially to the through holes of the opposite shaped link expansions ( 14 , 14 ′) of the element ( 12 ).

3. The apparatus according to claim 2 , which comprises contact means with driving wheels ( 13 ) and with idle wheels ( 15 ) of the high speed machine arranged at the ends of the pin ( 22 ) and at the top front and bottom front of each linked element ( 12 ).

4. The apparatus according to claim 3 , wherein the contact means are arranged beside the flanks of the central element ( 12 ′)and the pin has a length of at least the thickness of the two contact means in addition to the thickness of the central element and is locked at both ends.

5. The apparatus according to claim 4 , wherein the contact means with the driving wheels ( 13 ) and with the idle wheels ( 15 ) of the high speed machine comprise:

at least one anti-friction element ( 24 ) arranged coaxially to the pin ( 22 ); and/or

a damping element ( 26 ) arranged coaxially to the anti-friction element ( 24 ).

6. The apparatus according to claim 5 , wherein the anti-friction element ( 24 ) comprises at least one roller bearing.

7. The apparatus according to claim 5 , wherein the damping element ( 26 ) is arranged externally to the anti-friction element ( 24 ).

8. The apparatus according to claim 5 , wherein the damping element ( 26 ) is arranged internally to the anti-friction element ( 24 ).

9. The apparatus according to claim 5 , wherein the damping element ( 26 ) is arranged on the driving wheels ( 13 ) and/or on the idle wheels ( 15 ).

10. The apparatus according to claim 5 , wherein at least one angular reference element ( 20 ) is present on the surface of the central element ( 12 ′) of the element ( 12 ).

11. The apparatus according to claim 10 , wherein the idle wheels ( 15 ) include tighteners suitable for keeping the chain always tightened and for compensating the irregularity thereof.