Patent ID: 6173618
Filing Date: 2001-01-16
Classification: E21F

Abstract:
Apparatus for detecting the level of bulk particulate material in a shaft, the shaft having an interior surface, comprising:a flexible metal strap having a first surface and a second surface;a plurality of strain gages spaced apart from one another on the first surface of the metal strip, wherein deflection of the metal strip by bulk material in the region of a strain gage produces a change in resistance of the strain gage;a plurality of anchors for anchoring the metal strap to the interior surface of the shaft such that the metal strap is displaced a predetermined distance from the interior surface of the shaft, wherein the anchors are located intermediate the strain gages;a bridge circuit, having three fixed arms and a fourth arm, for detecting change in resistance of a strain gage;a control circuit for selectively coupling the strain gages into the fourth arm of the bridge circuit; anda display for displaying the location of a strain gage having a change of resistance.