The presence of the vent port377solves the problems of pump activation and pump cavitation. More specifically, when the massage water pump or the filter water pump activates, if the impeller is not entirely submerged in water and partially exposed to air, the impeller of the massage water pump...
and provide rotation for themselves. Thus, the shape and angle of blades2is then irrelevant, except with regard to flow rate efficiency. Indeed, in the exemplary embodiment shown in FIG. 6, blades2are thin to prevent inefficiencies in the flow of water and to reduce potential cavitation ...