Abstract: A hammer drill is provided including at least one cylinder, in which at least one piston is mounted such that it can be moved axially between an upper and a lower end position, wherein the cylinder has at least one lower fluid supply, which can be cyclically supplied with a drive fluid, wherein the cylinder is closed with an upper cover and a lower cover, wherein, in the lower end position, the piston is in contact with an inner side of the lower cover and a ring gap is formed between the entire casing surface of the piston and the inner wall of the cylinder. A method for deep drilling using a hammer drill of this type is also provided.

Abstract: A hammer drill is provided including at least one cylinder, in which at least one piston is mounted such that it can be moved axially between an upper and a lower end position, wherein the cylinder has at least one lower fluid supply, which can be cyclically supplied with a drive fluid, wherein the cylinder is closed with an upper cover and a lower cover, wherein, in the lower end position, the piston is in contact with an inner side of the lower cover and a ring gap is formed between the entire casing surface of the piston and the inner wall of the cylinder. A method for deep drilling using a hammer drill of this type is also provided.

Abstract: The invention relates to a drilling device for hard rock using a fluid, having at least one drill head with a pre-chamber and a mixing chamber where at least one front-facing nozzle and at least one rear-facing nozzle are provided. The fluid is mixed with abrasives in the mixing chamber, and the fluid together with the abrasives exits from the front-facing nozzle or an opening. The fluid flow is separated in the region of the pre-chamber, abrasive-free fluid exits the rear-facing nozzles, abrasives and the abrasive-free fluid are mixed in the mixing chamber, and the fluid mixed with the abrasives exits from the front-pacing nozzle or an opening.