Fluid-activated rotary drive device with a drive housing, in which is arranged at least one drive unit (24a, 24b) linearly displaceable by controlled fluid impact, which comprises a drive gearing on a longitudinal side, wherein a housing recess extending in a housing height direction and terminating in a housing upper side is formed in the drive housing, into which housing recess an output assembly is inserted from the housing upper side and with a lower side in front, which has an output body rotatable about a rotation axis oriented in the housing height direction and a roller bearing arrangement serving for the rotational bearing of the output body with respect to the drive housing, wherein the output body has an output sprocket in the interior of the drive housing in toothed engagement with the drive gearing of the at least one drive unit (24a, 24b) and has in the region of its upper side outside the drive housing at least one fastening interface serving for the force take-off, wherein the roller bearing arrangement consists of a roller bearing separate with respect to the drive housing and the output body, which roller bearing includes roller bearing components assembled to form an coherent structural unit in the form of an inner ring, an outer ring radially externally surrounding the inner ring, and rolling elements arranged between the inner ring and the outer ring, wherein the roller bearing is mounted from the lower side facing towards the drive housing coaxially on the output body and is supported with an upwardly directed upper front surface of its inner ring on a downwardly directed supporting surface of the output body and wherein the outer ring within the housing recess is supported with a lower front surface facing towards the drive housing on an upwardly directed supporting surface of the drive housing, wherein the inner ring of the roller bearing is axially braced with the supporting surface of the output body by first clamping means fixed to the output body and wherein the outer ring of the roller bearing is axially braced with the supporting surface of the drive housing by second clamping means fixed to the drive housing, wherein the first clamping means have a first clamping ring fixed to the output body, which is biased with the output body by means of fastening screws of the first clamping means screwed from underneath into the drive body and which abuts with its upper front surface against the lower front surface of the inner ring, wherein the inner ring is axially arranged between the downwardly directed supporting surface of the output body and the first clamping ring, and wherein the second clamping means comprise a second clamping ring fixed to the drive housing, which abuts with its lower front surface against the upper front surface of the outer ring, wherein the outer ring is axially arranged between the upwardly directed supporting surface of the drive housing and the second clamping ring, characterised in that the second clamping ring is fixed to the drive housing by means of fastening screws of the second clamping means screwed from above into the drive housing, that there is an axial spacing between the first clamping ring and the output body, so that there is an axial biasing of the inner ring with respect to the output body, and that there is a spacing between the second clamping ring and the output housing in the height direction of the drive housing, so that there exists an axial biasing of the outer ring with respect to the drive housing.