| 摘要 |
The invention relates to a drilling device provided with a boring rod (1), comprising a centred conveying channel (2) and an additional air supply channel and which supports a top hammer drilling head (5). A borehead annular chamber arranged between the boring rod (1) and the borehole wall is sealed, by means of a borehole seal, in relation to the atmosphere. The borehole seal is a circular annular shaped sealing disk (12) which is rotationally mounted on and axially secured to the boring rod (1), said sealing disk comprising several sealing lips (13), which are arranged on top of each other on the periphery thereof, and a central bearing sleeve (16) which is arranged on the inner periphery thereof. The central bearing sleeve is supported on an upper support ring (17) which is connected to the boring rod (1). The sealing disk (12) comprises several rigid annular disks (18), which are stacked on top of each other, and a rubber-elastic annular disk (19), which is arranged therebetween. The peripheral edge of the annular disk (19) protrudes above the rigid annular disks (18), thus forming the sealing lip (13) which is sealed in relation to a lining pipe (15) which is guided to the borehole wall (14) when the bore is lowered. |
