Abstract: For electric motor collectors with lamella inner cross members, which serve for anchoring the individual lamellas, protrude inwards running at least predominantly parallel to the collector axis and are provided with undercut surfaces, which are to be grasped from behind by reinforcing rings. Reinforcing rings are proposed which, aside from a metallic clamping ring, comprise a supporting ring, which is fitted positively into the metallic clamping ring and forms a double body with the clamping ring and is formed from a material, which is resistant to compression and insulating even at high operating temperatures. With this, reinforcing rings are produced from two partial rings, which are easily manufactured and easy to press together, or by the supporting ring which is brought into the clamping ring by injection molding. The reinforcing rings form a unit which can withstand extremely high thermal and mechanical stresses and imparts the collector with very high stability under load and fatigue endurance.