Arm rest for motor vehicle seats

An arm rest for motor vehicle seats having a backrest with lateral sides, comprising an elongated body and a load bearing structure incorporated in the body and including swinging mounting means of the arm rest comprising a connecting element adapted to be fixed relative to a lateral side of the backrest, a tubular end portion of the load bearing structure oriented transverse to the body, and a shaft coaxially inserted within said tubular end portion and having one end projecting from the body and secured to said connecting element in order to allow rotation on said shaft of said tubular end portion between a raised position and a lowered position of the arm rest, and stop means for stopping rotation of the arm rest in said raised and lowered positions, wherein said tubular end portion has an elastically deformable conformation in a radial direction and is formed interiorly with a pair of opposed axial ribs and with a pair of longitudinal recesses placed on opposite sides of and adjacent to each of said ribs, and wherein the seat is provided externally with a pair of opposed rigid axial projections cooperating with said axial ribs so as to constitute said stop means;

• said axial projections of the shaft having an outer radial dimension which is substantially equal to the inner radial dimension of said longitudinal recesses of the tubular end portion of the load bearing structure and which is substantially greater than the inner radial dimension of said tubular end portion between the longitudinal recesses adjacent to each other.