Positioning method for a drilling head

Abstract

Positioning method of a bit or a drill head (22) of a drilling device which drills an underground hole in which method devices which measure the situation of the drill head and/or receiving devices of signals which have been sent from elsewhere and are related to the mentioned measuring and equipment (3, 4) in order to convert the measurement data into a signal form which can be sent onto the ground surface, a possible battery (10) to be a power source and devices in order to send the signal from the drilling head (22), are located to the drilling head, most advantageously into a protected unit (6). The positioning data of the drill head (22) is clarified with the help of a signal sent from the ground surface so that the overground position from which sent signal is at its strongest when it is being received in the drill head (22) is searched and the position of the drill head is determined from this position to be located directly underneath and the depth position of the drill head (22) is determined as weakening of the signal which has been sent from the ground surface to the drill head (22) wherein the experimentally defined weakening of the signal per a ground metre is used in order to determine the depth position and the data detected at the drill head (22) are sent to the ground surface either by radio along a drill rod pipe (9) or from the drill head (22) through the ground onto the ground surface the shortest way possible.

Dependencies are inferred from the claim text.