#$%^&*AU2013224742B220150507.pdf#####SURGICAL STAPLING APPARATUS WITH POWERED ARTICULATION ABSTRACT An articulation mechanism (1) for a surgical instrument (10) is provided. The articulation mechanism (1) comprising: a transmission shaft (7); a speed reducing mechanism disposed in mechanical cooperation with the transmission shaft (7); a clutch (9) operatively coupled to the speed reducing mechanism; a frame; and a yoke shaft (10a) operatively connected to the clutch (9) and the frame, wherein the yoke shaft (10a) advances the frame linearly upon rotation of the transmission shaft (7).