An expansion anchor of the generic type is known, for example, from U.S. Pat. Publ. No. 2010/0135743 A1. It is used to anchor objects to a hole drilled in a solid substrate, for example, in concrete. The prior-art expansion anchor has an elongated stud that is provided with an expansion cone in the area of its front end. The expansion cone widens towards its front end, that is to say, counter to the pull-out direction. An expansion sleeve is arranged on the stud in a way that is offset to the expansion cone in the pull-out direction. This expansion sleeve is supported on the stud so as to be movable on the expansion cone towards the front end of the stud. The expansion sleeve has elevations which protrude radially on the outside and with which the expansion sleeve can dig into the inner wall of the hole drilled in the substrate. With its first end facing forward, the expansion anchor is hammered into the drilled hole counter to the pull-out direction, and subsequently the stud is pulled somewhat out of the drilled hole in the pull-out direction. After the expansion anchor has been hammered in, the expansion sleeve digs into the inner wall of the drilled hole and is thus held back in the drilled hole when the stud is pulled out. In this manner, the expansion cone of the stud is pulled into the expansion sleeve, whereby the expansion sleeve is expanded due to the increasing diameter of the expansion cone. In this process, the expansion anchor is wedged with the expansion sleeve in the substrate so that tensile loads can be transmitted into the substrate. This basic principle can preferably be realized with the invention as well.
According to the above-mentioned U.S. Pat. Appln. No. 2010/0135743 A1, an expansion element made of a material having a Vickers hardness of between about 218 HV and 290 HV and a sleeve made of a material having a Vickers hardness of between about 218 HV and about 290 HV are provided.
USPTO Backgrounds
USPTO Backgrounds