Level detecting

Liquid level detection apparatus and other apparatus comprising in common an elongated flexible substrate transducer which can extend into a liquid containing vessel or be applied to other pressure or force measurement tasks and provide an accurate indication of liquid level or other pressure or force related parameter through a voltage drop measurement made through an elongated, e.g., sinuous or other regular pattern (or of irregular patterning to localize areas of highest sensitivity) conductor pattern contained in the transducer which is shorted out in the portion thereof subjected to a predetermined pressure, the elongated conductor being on facing portions of a folded sheet substrate material which has an inherent spring characteristic (resilience) and/or geometrical-arrangement-loading such that the portion thereof subjected to such pressure has butting face portions and the portion thereof not subjected to such pressure is separated due to the spring characteristic of the folded sheet material. For instance, as applied to liquid level measurement, the folded substrate is in elongated ribbon form and the portion below liquid level is subjected to liquid pressure sufficient to move the two facing portions in butting engagement causing elongated conductor patterns thereon to short out at liquid level.