Patent 7661902 was granted and assigned to ZF Friedrichshafen on February, 2010 by the United States Patent and Trademark Office.
A ball and socket joint has high stability of the bearing shell and hence of the joint and reduces the transmitted structure-borne noise from the viewpoint of increased comfort with a bearing shell design with at least two layers. The inner layer is formed of a metal and the outer layer of a plastic such as polyoxymethylene.