Hydraulic device including an improved assembly of a hydraulic machine and a clutch

The apparatus has a hydraulic machine (30) comprising a machine shaft (40) having a proximal end (41) and a distal end (42). A clutch (20) comprises a clutch shaft (50) having a proximal end (51) and a distal end (52). An engaging unit comprises two sets of friction disks. The disks are arranged around the machine shaft. The distal end of the clutch shaft is bell-shaped so as to surround the proximal end of the machine shaft, where the bell shape defines an inner space in which the proximal end of the machine shaft and the friction disks linked to the clutch shaft are located.