A volumetric gear machine interacting with a working fluid comprising: a first toothed wheel (3) with helical teeth comprising a first tooth (31) in turn comprising a first and a second flank (311, 312) opposite each other; a second toothed wheel (4) with helical teeth having two opposite flanks, the first and the second wheel (3, 4) being operatively coupled in a meshing area (2). At a portion of the meshing area (2), the first and the second flank (311, 312) being in simultaneous contact with the second wheel (4).