AUDIO-ELECTRONIC LEVEL Russian patent published in 1997 - IPC

FIELD: construction instruments. SUBSTANCE: this instrument can be used in civil engineering, carpentry, and in household affairs for example for checking shelves for horizontal position or drilled hole for verticality. Audio-electronic level has body with at least one resting plane. Located inside body with possibility for fixed turning is sensitive element, also accommodated there is electronic unit with output audio signalling device. Sensitive element is in the form of vial with feeding and measuring electrodes immersed in electrically conducting liquid which is nonuniform as to density and electrical conductivity. Electronic unit is made in the form of generator with its outputs connected to feeding electrodes of vial, and nonlinear phase-sensitive detector with its input connected to measuring electrode of vial. Input of audio signalling device is connected to nonlinear phase-sensitive detector with its control input connected to generator synchronization output. EFFECT: high efficiency. 6 cl, 9 dwg