Device for uncoupling loaded shafts, for a power transmission unit

The invention relates to a device for uncoupling the drive shaft (2) of a piece of equipment from an input shaft (3). The device includes a claw (5) provided with first teeth (8) and first splines (6) in order to (i) move longitudinally along a first of the shafts (2) by co-operating with second splines (7) borne by the second of the shafts (3) and (ii) engage or disengage the first teeth (8) in relation to the second teeth (9) positioned on the second shaft (3). The device also includes a longitudinal movement means comprising a stationary part (10) acting on a longitudinally mobile piece (11) in order to move the claw (5) between a coupling position and an uncoupling position. The invention is characterised in that the longitudinal movement means drives the claw (5) by means of co-operation between a rotationally fixed piece (13) and a piece (14) which is linked to the claw and rotated therewith, a longitudinal clearance (15) being maintained during operation between the piece that is rotationally fixed and