The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 17, 1984
Filed:
Jun. 12, 1981
Klaus Albrecht, Liederbach, DE;
Martin Haub, Steinbach, DE;
VDO Adolf Schindling AG, Frankfurt am Main, DE;
Abstract
A device for the electric monitoring of the level of a liquid contained in a container, comprising at least one temperaturedependent resistance sensor immersed in the liquid the level of which is to be monitored, a constant current source being connectable to the resistance sensor under the control of a program control device controlling a device for detecting and storing the initial voltage drop on the resistance sensor at an initial time and the measurement voltage at a specified time after connection of the constant current source, and a device for evaluating the voltages by subtracting the measurement voltage from the initial voltage and under the circumstances inverting the difference to form a display voltage which corresponds to the level of the liquid. Several of these resistance sensors are arranged at different levels within the container, the sensors being connectable one after the other, controlled by the program control device, to the constant current source and to the device for evaluating the voltage drop on them. A fixed-value storage provides a supply of fixed-value voltages one of which respectively is selectably dependent on the respective resistance sensor active at the time, and an adder is appliable in order to form the display voltage, with the evaluated voltage which is analog to the depth of immersion of the active resistance sensor and with the fixed-value voltage which corresponds to the height of that resistance sensor.