Variable length steering shaft for steering mechanisms of motor vehicles

A variable length steering shaft for steering mechanisms of motor vehicles, comprising:

• an external profile tubular member having a non-circular cross-section;
• an internal profile member arranged coaxially with the external profile member and having an end portion thereof received in the external profile tubular member, the internal profile member being axially displaceable within the external tubular member and forming with the external profile tubular member a circumferential gap having a variable width;
• and
• a slide sleeve formed of a macromolecular material and arranged in the gap formed by the external and internal profile members for form lockingly connecting the external and internal profile members for transmitting a torque therebetween,
• wherein the internal profile member has an outer circumferential contour which at least sectionwise approximately corresponds to an inner circumferential contour of the external profile tubular member,
• wherein the outer circumferential contour of the internal profile member and the inner circumferential contour of the external profile tubular member are at least partially formed each of a plurality of following each other convex and concave sections with radii of the convex and concave sections being respectively located inside and outside of a respective profile member,
• wherein the slide sleeve has outer and inner circumferential surface portions engageable with respective walls of the external and internal profile members alternatively and only sectionwise, with respective surface portions alternatively engaging the convex sections of the internal profile member, and
• wherein regions of the slide sleeve engaging the concave section of the external profile member have each an elongate groove formed therein which provides for a surface contact of respective engaging regions of the slide sleeve with the concave section of the external profile member.