1. Field of the Invention
The invention, in general relates to a dishwasher and, more particularly, to a dishwasher provided with a device for substantially preventing the formation of foam and air bubbles in a dampened flow measuring zone of a turbidity sensor disposed in the water circulation path.
2. The Prior Art
In program controlled dishwashers which utilize turbidity sensors for optimizing the washing cycle the problem may arise that dirt particles suspended in the wash fluid as well as foam and air bubbles caused by food residue may move through the measuring path of the sensor and, as a function of the contaminants and admixed air, generate noisy analog measurement signals of uncontrollable voltage levels at the output of a photo receiver. While the noisy signals characterize the degree of contamination of the wash fluid at any given time, they are distorted by the accompanying portion of bubbles and/or foam. As a result, digital signal processing corresponding to the actual degree of wash fluid contamination for controlling the washing operation is complicated. To prevent this problem, it has been proposed to move the wash fluid within the measuring zone at a dampened flow.