Quick-fit connection assembly

A connection assembly, comprising:

• a connecting element suitable for allowing a fluid sealed passage through a wall, said connecting element comprising a main body which has tubular shape and extends according to a longitudinal direction of main development,
• said main body having a first terminal end portion and a second terminal end portion mutually opposite along said longitudinal direction, and further comprising a lateral external surface covered and at least partially threaded, wherein said external surface comprises a first region wherein the thread is absent;
• a washer comprising:
• a second main body having an annular shape, comprising a through hole developing according to said longitudinal direction, wherein said hole is defined by an internal side surface of said second main body configured to engage with said external surface of said connecting element, and
• interference components configured to assume:
• a rest position, wherein they are at a maximum distance from said second main body and
• an operating position, wherein they interfere at least partially with said hole,
• wherein said interference components comprise an interference element connected or connectable to said second main body and having a main development direction orthogonal to said longitudinal direction,
• wherein said interference element:
• has a central region connected or connectable at a first end portion thereof to said second main body and comprises a nosepiece element at a second end portion thereof,
• wherein said central region has a facilitated folding portion in such a way as it can be folded to carry said nosepiece from said rest position,
• wherein said nosepiece is at a maximum distance from said second main body, to said operating position, wherein said nosepiece interferes at least partially with said hole,
• wherein said nosepiece is configured to engage with said first region of said connecting element,
• the configuration of said washer being such that said interference components are configured to engage with said first external region of said connecting element and said internal side surface is configured to engage with said external surface of said connecting element when said connecting element is inserted inside said through hole, and
• the configuration of said connecting element being such that said first region is configured in such a way as to realize a coupling seal with said nosepiece,
• wherein said first region has an at least partially flat extension in extending along said longitudinal direction.