SHAFT BEARING IN A ROCK AND GROUND-DRILLING MACHINE

摘要

A rock or ground-drilling machine includes a gear housing (14) in which there is journalled a shaft (31) which surrounds a drill string (23) in the manner of a sleeve and which is affixed to the drill string by means of a chuck (7) connected to the shaft (31). The chuck is operated by means of pressure fluid delivered to the chuck (27) through the medium of a commutator (36) acting between the gear housing (14) and the shaft (31). The shaft (31) is journalled in the gear housing (14) by means of one single rolling bearing (39). The commutator (36) lies resiliently against the gear housing (14) and is flexible in response to sideways movement of the shaft (31).