Closure system of the interconnection of transport units connected to each other in a convoy

1. A closure system for connecting two contiguous transport units in a convoy for the transport of goods, said closure system comprising an accordion-shaped element configured to change a length of the accordion-shaped element along a longitudinal axis of said convoy, the accordion-shaped element vertically extending along a vertical axis and transversally extending along a transversal axis, said vertical axis and said transversal axis being perpendicular to said longitudinal axis, characterized in that the accordion-shaped element comprises a central portion and a pair of outer portions placed on opposite sides with respect to said axis, a thickness of said outer portions on a plane defined by said longitudinal and vertical axis decreasing from said central portion to said outer portions along said transversal axis.

2. The closure system according to claim 1 , wherein the thickness of said outer portions linearly decreases starting from the respective connection with said central portion until reaching a minimum value at the end of said outer portions.

3. The closure system according to claim 1 , wherein said central portion and said outer portions each comprise a corrugated profile.

4. The closure system according to claim 3 , wherein said corrugated profiles comprise curved axial end portions and flat intermediate portions.

5. The closure system according to claim 3 , wherein the corrugated profile of said central portion and the corrugated profile of said outer portions are continuous between one another.

6. The closure system according to claim 3 , wherein said corrugated profiles each define corrugations defining a pitch along said longitudinal axis.

7. The closure system according to claim 1 , wherein said central portion comprises a plurality of flanges, said flanges being carried by said corrugated profile.

8. The closure system according to claim 7 , wherein said flanges are carried by said corrugated profile so that they are all arranged on a same side of the latter.

9. The closure system according to claim 1 , wherein said accordion system is made in a single piece.

10. The system according to claim 1 , wherein said accordion system is moulded.

11. The system according to claim 1 , wherein said accordion system is made of rubber.

12. A convoy comprising a plurality of transport units connected with each other, said convoy comprising a closure system according to claim 1 , said closure system being interposed between two transport units contiguous to one another.