Abstract: A positive-displacement reciprocating compressor, comprising a plunger slidingly coupled inside a cylinder, in which a compression chamber is located, and operatively connected to a motor which put it in motion inside the cylinder. The motor has a rotation shaft coupled with an eccentric cam mechanically connected to the plunger and able to impose longitudinal displacements to the plunger according to an orthogonal direction with respect to the rotation axis of the shaft.