Flexible protective bellows dimensioned against external projections

The invention relates to a protective bellows (16, 100) transmission or direction, adapted to protect a mechanism (7), said bellows (16, 100) being flexible and extensible, and having a succession of folds to define a series of recesses (31) and a series of bumps (30) alternately, said bellows (16, 100) being closed so as to define a conduit. The main characteristic of a bellows (100) according to the invention is that it includes extensions (102, 103, 104) of deformable material originating at some bosses (30), said extensions (102, 103, 104 ) encircling the bellows (100) and being disposed so as to cover all the folds of the bellows (100), regardless of the deformation undergone by the bellows (100).