A delivery assembly for a machine for the preparation of liquid products using cartridges includes: an injector device, capable of introducing into the cartridge water and/or steam under pressure, an infusion chamber facing the injector device and capable to receive the cartridge, an actuation system, designed to cause displacements of the infusion chamber between a spaced position and a close position with respect to the injector device, a loading arrangement that includes an inlet passage and retention means, switchable between a retention condition and a release condition of the cartridge by means of displacements of the infusion chamber with respect to the injector device. The delivery assembly further includes ejector means, functionally distinct from the retention means and capable of pushing the cartridge towards the outside of the infusion chamber in function of the displacement of the infusion chamber towards its spaced position from the injector device.