having a truncated cone shape with the intention of varying the passage area entrance of the additive dispenser 60 thus increasing the velocity at which the wash water arrives in such a way that the greater diameter end 72 of the referred to connection nozzle 71 is located near the supply hose 61 and distant from the inner part of the additive dispenser and where through the other side of the lesser diameter end 73 consequently is located near the inner part of the additive dispenser 60 and distant from the supply hose 61 additionally together with the connection nozzle 71 immediately after the smaller diameter end 73 a segment is found neck shaped 76 which directs the wash water flow towards the next element of the flow homogenizing system 70 of the additive dispenser 60 a damping tank 74 has been included as part of the flow homogenizing system 70 with the objective of dissipating the kinetic energy which was gained by the wash water flow as a consequence of increased velocity which it acquires upon passing through the inner part of the connection nozzle 71 thus functioning in a hydraulic jump manner knowing that the hydraulic jump is a sharp rise of the water level in a channel or in a container space as a consequence of the delay which a water current suffers when it flows at a high velocity causing a dissipation of kinetic energy in the case of the flow homogenizing system 70 of the additive dispenser 60 the hydraulic jump.