US Patent 9869334 Expansion anchor with grooves in the expansion cone

An expansion anchor with a bolt and at least one expansion element is disclosed. An oblique surface is arranged in the region of the first end of the bolt and forces the expansion element radially outward on the bolt if the bolt is displaced in a pull-out direction relative to the expansion element. The bolt has, in the region of its rear end facing away from the first end, a load-absorber which is suitable for introducing tensile forces which are directed in the pull-out direction into the bolt. At least one groove which is closed with respect to the first end is made in the oblique surface, which groove reduces the contact surface between the expansion element and the oblique surface.