A coffee machine includes an infusion zone, a storage container for ground coffee arranged above the infusion zone, and a device for transferring the coffee grounds from the storage container to the infusion zone via an aperture. The transfer device includes a member for opening and closing the aperture, which can move between an open position and a closed position. The aperture opening and closing member includes an open portion that has an inclined wall configured, when in the open position, to be positioned beneath the aperture and to direct the coffee grounds that pass through said aperture towards the infusion zone, and configured to be offset from the aperture when in the closed position. The transfer device also includes a cleaning member for the inclined wall when moving from the open position into the closed position and vice versa.