A dispensing device for dispensing a granular material, comprising a dispensing channel (20) provided with an inlet opening (21) and an outlet opening (22). The dispensing channel (20) comprises an intermediate portion (23), which connects the inlet (21) and outlet (22) openings and is provided with a longitudinal axis (Y); the intermediate portion (23) has a length (L) and a height (H), measured on a vertical plane containing the longitudinal axis (Y), wherein the height (H) is measured perpendicular to the length (L). The intermediate portion (23) is configured to enable the deposit and accumulation of a predetermined quantity of granular material coming from the inlet opening (21); Motor means are provided which can be activated on command to cause the granular material to flow in advancement from the intermediate portion (23) towards the outlet opening (22).