Klaas Spaargaren: Capacitive level gauge. Shell Oil Company, November 19, 1985: US04553434 (26 worldwide citation)

An improved sectionalized capacitive level gauge is provided. A screen member having appropriate openings therein is positioned between a set of sectionalized first members and a second member of a capacitive level gauge.

Klaas Spaargaren, Adrianus C W Leyen: U-shaped capacitor level gauge. Shell Oil Company, September 16, 1986: US04611489 (13 worldwide citation)

A device for determining the position of an interface between different fluids in a tank or container is provided. This device has a plurality of cells, placed one below another and mounted on a structure which is placed in the tank or container, each cell consisting of three electrically conductive ...