Expanding drill device for expanding a pilot bore created from a starting point to a target point in the ground along a specified drilling line by moving the expanding drill device along the specified drilling line in order to create a bore in the ground or in rock for introducing a pipeline or a supporting system into the expanded bore: having a housing; having a drill side and having a rear side opposite the drill side; having a drill head that has a cutting wheel, which is arranged on the drill side of the expanding drill device so as to be mounted and driven rotatably about a rotational axis and relative to the housing and on which at least one drill tool for loosening the ground or the rock is arranged; having a drill-side connection for producing a connection to a pipe section located in the pilot bore on the drill side; having a rear-side connection for the pipeline to be introduced on the rear side of the drill head; wherein the drill side centrally has at least one receiving chamber for the loosened ground or the loosened rock, said receiving chamber being connected via at least one removal opening to a material-conveying device of the expanding drill device for the loosened ground or the loosened rock, wherein the drill side has at least one drill chamber in which the cutting wheel is arranged, which is arranged around the receiving chamber, wherein the cutting wheel is annular and is arranged rotatably about the central receiving chamber, and wherein the receiving chamber is connected via at least one conveying opening to the drill chamber so that the loosened ground or the loosened rock can be conveyed through the conveying opening into the receiving chamber, characterized in that at least one crusher is provided in the drill chamber, that the crusher has crusher bars on the rotatable cutting wheel, which move together with the cutting wheel, and crusher bars on a side of the receiving chamber facing the drill chamber, which are fixedly arranged together with the receiving chamber, and that the crusher bars (47, 49) are arranged relative to one another such that a crusher gap exists between the crusher bars. having a housing; having a drill side and having a rear side opposite the drill side; having a drill head that has a cutting wheel, which is arranged on the drill side of the expanding drill device so as to be mounted and driven rotatably about a rotational axis and relative to the housing and on which at least one drill tool for loosening the ground or the rock is arranged; having a drill-side connection for producing a connection to a pipe section located in the pilot bore on the drill side; having a rear-side connection for the pipeline to be introduced on the rear side of the drill head; wherein the drill side centrally has at least one receiving chamber for the loosened ground or the loosened rock, said receiving chamber being connected via at least one removal opening to a material-conveying device of the expanding drill device for the loosened ground or the loosened rock, wherein the drill side has at least one drill chamber in which the cutting wheel is arranged, which is arranged around the receiving chamber, wherein the cutting wheel is annular and is arranged rotatably about the central receiving chamber, and wherein the receiving chamber is connected via at least one conveying opening to the drill chamber so that the loosened ground or the loosened rock can be conveyed through the conveying opening into the receiving chamber, characterized in that at least one crusher is provided in the drill chamber, that the crusher has crusher bars on the rotatable cutting wheel, which move together with the cutting wheel, and crusher bars on a side of the receiving chamber facing the drill chamber, which are fixedly arranged together with the receiving chamber, and that the crusher bars (47, 49) are arranged relative to one another such that a crusher gap exists between the crusher bars.