Telescopic shaft

摘要

A telescopic shaft for use in a motor vehicle steering column. The telescopic shaft comprises at least two tubular members of circular cross section which fit one into the interior of the other. The tubular members have longitudinally grooved regions which define a set of longitudinal ribs and are meshed with one another. Such meshing prevents relative rotational movement between the tubular members and allows relative axial movement therebetween. At least one of the tubular members includes at least one projection directed toward the other tubular member(s) and engaging an end of at least one longitudinal rib. Sliding of the tubular members with respect to one another can only occur when deformation of the longitudinal rib(s) engaged by the projection(s) also occurs. The telescopic shaft therefore provides a braking action whenever it is forcefully collapsed.