An electrical switch sensitive to an externally applied inertial and gravitational force, having an enclosure with a closed space; a conductive fluid filing a first portion of the space and a non-conductive medium filling a second portion of the space, the conductive fluid and the non-conductive...http://www.google.fr/patents/US5751074?utm_source=gb-gplus-shareBrevet US5751074 - Non-metallic liquid tilt switch and circuitry
