Abstract: A pot-shaped, cold-formed steel brake piston as a pot which is open on one side includes a base and a wall including inner and outer walls, a radially inwardly configured groove is open in a radially outward direction and forms, radially at the inside, a groove bead projection. The open side of the pot ends as a bearing for a friction pad backplate. Interfaces integrated at the inside on the end side serve a) for the fixing between friction pad and steel brake piston and b) as support bearing for spring mounting the friction pad. An aspect is a further improved steel brake piston of the new generation. The minimum inner diameter dimin is axially set back in the direction of the base by a multiple of the length of a wall thickness s, and the minimum piston inner diameter dimin is formed by the groove bead projection.

Abstract: A pot-shaped, cold-formed steel brake piston as a pot which is open on one side includes a base and a wall including inner and outer walls, a radially inwardly configured groove is open in a radially outward direction and forms, radially at the inside, a groove bead projection. The open side of the pot ends as a bearing for a friction pad backplate. Interfaces integrated at the inside on the end side serve a) for the fixing between friction pad and steel brake piston and b) as support bearing for spring mounting the friction pad. An aspect is a further improved steel brake piston of the new generation. The minimum inner diameter dimin is axially set back in the direction of the base by a multiple of the length of a wall thickness s, and the minimum piston inner diameter dimin is formed by the groove bead projection.