Strain-wave gearing

A strain-wave gearing, comprising:

• a first assembly,
• a flexible gearing element attached to the first assembly, the flexible gearing element being a flanged bushing and provided with an external toothing,
• a wave generator provided for deforming the flexible gearing element, and
• an output-side assembly which has an internal toothing meshing with the external toothing of the flexible gearing element,
• wherein the output-side assembly is mounted in the first assembly by a rolling bearing, wherein the rolling bearing is sealed on both sides by a first seal and a second acting between the first assembly and the output-side assembly, and wherein the first seal delimits a lubricant chamber on the side thereof facing away from the rolling bearing, which extends as far as the external toothing of the flexible gearing element and the internal toothing of the output-side assembly,
• wherein the first seal is arranged between an end face of the output-side assembly and a collar of the flexible gearing element, wherein the first seal is a contact seal which contacts the collar, wherein the first seal has a metal core which is inserted into a front-side groove of the output-side assembly.