surrounds the shaft 9 and has at its end one or two rectangular cutouts 15 located symmetrically relative to one another for the purpose of providing a housing with one or two longitudinal extensions called the second extensions 16 of the dog clutch 14 the dog clutch 14 has an annular shape surrounding the support shaft 9 and has a shoulder or collar 17 extending radially and from which two extensions extend longitudinally on both sides of the collar 17 said longitudinal extensions each have the shape of a cylindrical angular sector of which the amplitude corresponds to that of the cutouts made for the first extension 18 in a radial face of the ball joint 10 and for the second extension 16 in the second bushing 12 during the mounting of the assembly the penetration of the first and second longitudinal extensions 18 and 16 of the dog clutch respectively in the cutouts 13 and 15 of the ball joint 10 and of the second bushing 12 permit the fixing in rotation about the shaft 9 of the ball joint 10 with the dog clutch 14 and with the bushing 12 by preventing any possibility of rotation to the second bushing 12 via a simple wrench.