The invention relates to a gear pump in particular for rubber mixes, comprising an enclosure in which rotates a set of gear wheels comprising a central gear wheel which cooperates with two other peripheral gear wheels, said pump comprising at least one feed chamber in which acts at least one feed means for delivering the material to said enclosure via at least one passage orifice, each of the gear wheels being driven directly by a driving torque and prestressing means between the teeth ensuring hermetic contact of the meshing zone of the central wheel with each of the two peripheral wheels.