STEERING COLUMN COMPRISING A PLASTIC SLIDING SLEEVE

• US 20100307280A1
• Filed: 01/09/2009
• Published: 12/09/2010
• Est. Priority Date: 01/18/2008
• Status: Active Grant

• Current Assignee: ThyssenKrupp Presta AG (Thyssenkrupp AG)
• Original Assignee: ThyssenKrupp Presta AG (Thyssenkrupp AG)
• Inventors: Schnitzer, Rony
• Granted Patent: US 8,549,953 B2
• Time in Patent Office: Days
• US Class Current: 74/493
• CPC Class Codes: B62D 1/185 adjustable by axial displacement, e.g. telescopically B62D1/183, B62D1/187, B62D1/19 take precedence
• CPC Class Codes: Y10T 29/49908 Joining by deforming

Abstract

The invention relates to a steering column for a motor vehicle, comprising a bracket (1) which carries an upper jacket unit (3) and a lower jacket unit (5), wherein the jacket units (3, 5) surround a steering shaft (8) rotatably mounted therein, and wherein the jacket units (3, 5) comprise an inner jacket tube (10) and an outer jacket tube (11) which surrounds the inner jacket tube (10) at least in some sections, said jacket tubes being mounted such that they can be displaced one inside the other in their axial direction by means of a plastic sleeve (6) made of thermoplastic which is located therebetween. Freedom from play is achieved in that the plastic sleeve (6) is inserted into the outer jacket tube (11) with a press fit, and in that the outer jacket tube (11) has at least one opening (12), in the region of which the plastic sleeve (6) is pressed against the inner jacket tube (10) by deformation.

Claims

1. Steering column for a motor vehicle, comprising a bracket which carries an upper jacket unit and a lower jacket unit, wherein the jacket units surround a steering shaft rotatably mounted therein, and wherein the jacket units comprise an inner jacket tube with an outer surface and an outer jacket tube which surrounds the inner jacket tube at least in some sections, said jacket tubes being mounted such that they can be displaced one inside the other in their axial direction by means of a plastic sleeve made of thermoplastic which is located therebetween and which has an inner surface directed towards the inner jacket tube and an outer surface directed towards the outer jacket tube, wherein the plastic sleeve is inserted into the outer jacket tube with a press fit, and wherein the outer jacket tube has at least one opening, in the region of which the plastic sleeve has, on its inner surface, protrusions towards the inner jacket tube, at which the plastic sleeve is pressed against the outer surface of the inner jacket tube.

2. The steering column according to claim 1, wherein at least one cut-out is formed in the outer jacket tube, in the region of which cut-out the plastic sleeve has on its inner surface a further protrusion, the distance of which from a central axis of the jacket tubes is smaller than the distance of the outer surface of the inner jacket tube in the region of the protrusion.

3. The steering column according to claim 2, wherein the further protrusion is designed as a breakaway element, wherein, when a certain force acting on the jacket tubes in the direction of displacement of these jacket tubes is exceeded, the further protrusion is designed to break away and enable the displacement.

4. The steering column according to claim 1, wherein the jacket tubes and also the plastic sleeve have circular cross-sections.

5. The steering column according to claim 1, wherein the openings are provided in at least two axially spaced-apart positions relative to the axial direction of the jacket tubes.

6. The steering column according to claim 1, wherein the openings are configured as round bores or punched-out holes.

7. The steering column according to claim 1, wherein the openings are configured as slots which run at least partially in the circumferential direction of the outer jacket tube.

8. The steering column according to claim 1, wherein a spring element is provided which passes through at least one opening and is held under pretension against a surface area of the outer surface of the plastic tube in the direction of the inner jacket tube.

9. A method for producing a telescopic steering column for a motor vehicle, comprising a bracket which carries an upper jacket unit and a lower jacket unit, wherein the jacket units surround a steering shaft rotatably mounted therein, and wherein the jacket units comprise an inner jacket tube with an outer surface and an outer jacket tube which surrounds the inner jacket tube at least in some sections, said jacket tubes being mounted such that they can be displaced one inside the other in their axial direction by means of a plastic sleeve made of thermoplastic which is located therebetween, the method comprising inserting the plastic sleeve into the outer jacket tube with a press fit, introducing the inner jacket tube into the plastic sleeve with a sliding fit, and, in the region of at least one opening of the outer jacket tube, pressing the plastic sleeve against the inner jacket tube by plastic deformation.

10. The method according to claim 9, further comprising, in the region of at least one opening of the outer jacket tube, forming a protrusion in the plastic sleeve by plastic deformation, the distance of which protrusion from a central axis of the jacket tubes is smaller than the distance of the outer surface of the inner jacket tube in this region.

11. The method according to claim 9, wherein the plastic deformation takes place under the effect of heat.

12. The method according to claim 9, wherein the plastic deformation takes place under the effect of ultrasound and radial pressure.

13. The method according to claim 9, wherein the deformation takes place at least at two locations which are spaced apart from one another in the axial direction of the plastic sleeve.

14. The method according to claim 9, wherein the inner jacket tube has a smooth outer surface which, even after the bearing of the plastic sleeve due to the local deformation, allows a displaceability and/or rotatability of the inner jacket tube in the plastic sleeve.