초록 ▼

A system for measuring level of material in a vessel that includes a transmission line probe adapted to be positioned for contact with material in the vessel. Electronics are coupled to the transmission line probe for launching microwave radiation along the probe and detecting radiation reflected by

A system for measuring level of material in a vessel that includes a transmission line probe adapted to be positioned for contact with material in the vessel. Electronics are coupled to the transmission line probe for launching microwave radiation along the probe and detecting radiation reflected by the electrical impedance discontinuity presented at the air/material interface in the vessel. Level of the air/material interface within the vessel is determined employing time domain reflectometry techniques, and is displayed as a continuous function over a predetermined range. The system range is calibrated by means of a target selectively manually positionable along the probe rod while the probe is disposed outside of the vessel. First and second signals are selectively stored in the system electronics with the target disposed at positions along the probe rod corresponding to the ends of the material level measurement range. The electronics are thereafter operable to display level of the air/material interface along the probe within the vessel over the predetermined range between the selected positions of the target along the probe rod. The end of the probe rod is at an angle of 90.degree. to the remainder of the probe to eliminate material level ambiguity at the probe end.

대표청구항 ▼

[ What is claimed is:] [1.] A system for measuring level of material in a vessel that comprises:a transmission line probe adapted to be positioned for contact with material in the vessel such that an impedance discontinuity is presented along said probe at the air/material interface in the vessel,me

[ What is claimed is:] [1.] A system for measuring level of material in a vessel that comprises:a transmission line probe adapted to be positioned for contact with material in the vessel such that an impedance discontinuity is presented along said probe at the air/material interface in the vessel,means for launching microwave radiation along said probe such that a portion of such radiation is reflected from said impedance discontinuity,means responsive to said reflected energy portion for determining level of said air/material interface with respect to said probe employing time-domain reflectometry,means responsive to said level-determining means for displaying level of said interface as a continuous function over a predetermined range, andmeans for calibrating said displaying means to said predetermined range with said probe disposed outside of the vessel comprising target means for selective positioning along said probe to reflect microwave radiation, and means coupled to said level-determining means for storing at least one signal indicative of one end limit of said range when said target means is at a first position along said probe, said level-determining means thereafter cooperating with said displaying means to indicate level of the air/material interface along said probe over said predetermined range with respect to said one end limit of said range.