HYBRIDATION HYDRAULIQUE LEGERE ET ENTRAINEMENT D'UNE PRISE DE FORCE SUR MOTEUR INDUSTRIEL

The invention relates to a light hybrid drive device, comprising: an internal combustion engine MCI (10) that is coupled to a main receiver RP (14) and a fixed displacement pump/engine unit (20); a hydraulic circuit (30) that contains, in addition to the pump/engine unit (20), a hydraulic engine (36) for rotating a secondary take-off drive (37); a high-pressure accumulator (44); and a low-pressure tank (46). The device also comprises: a main three-stage hydraulic valve (50) that is located between a portion (34) of the hydraulic circuit (30), containing the pump/engine unit (20), and another portion (32) of the hydraulic circuit (30), containing the hydraulic engine (36); a hydraulic clutch distributor (56) arranged in parallel with the pump/engine unit (20); a hydraulic engine distributor (58); a hydraulic pressure regulator (64) comprising an inlet Er for controlling the level to which the regulator opens in order to control the flow of fluid in the hydraulic engine (36); a hydraulic accumulator valve (60); and a computer UC (70) that is configured so as to control the stages of the hydraulic valves (50, 56, 58, 60), the degree to which the pressure regulator (64) opens, and the engine speed of the internal combustion engine MCI (10) on the basis of various operational configurations of the device. The invention is of use in the hybridization of internal combustion or electrical engines by means of a hydraulic circuit comprising a related power take-off.