Patent ID: 8083010

Claim:
Drilling device for drilling a hole into ground or rock or for reaming a predrilled hole, which drilling device comprises: several outer hammering bits placed in a circular shape about a central axis, each said outer hammering bit being equipped with a respective longitudinal hammer drill machine, whereby in use the outer hammering bits together drill an outer circumferential portion of a hole; a casing tube which is pulled out of and pushed into the drilled hole created during drilling with the outer hammering bits, said casing tube being essentially located about the central axis; a tubular, rotatable drill rod tube located centrally of the casing tube, wherein the longitudinal hammer drill machines are placed in a circular shape, and the longitudinal hammer drill machines are each attached to an outer surface of the drill rod tube via at least one joint/hinge attachment essentially in a drilling direction, and wherein a rotation of the drill rod tube a) in a first direction hingeingly rotates the hammer drill machines and associated outer hammering bits, via the joint/hinge attachments of the respective hammer drill machines, outwardly from the drill rod tube towards the casing tube to an outward position to drill the outer circumferential portion of the hole, and b) in an opposite, second direction hingeingly rotates the hammer drill machines and associated outer hammering bits, via the joint/hinge attachments of the respective hammer drill machines, inwardly towards the drill rod tube to an inward position so that the hammers and associated bits are able to be pulled away with the drill rod tube from inside of the casing tube, and further including a rotating flange which rotates with the drill rod tube, said rotating flange being arranged to turn all of the hammer drilling machines simultaneously as desired outwardly from or inwardly towards the drill rod tube.