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:
Jun. 23, 1987
Filed:
Oct. 01, 1984
Jurgen Lau, Weil am Rhein, DE;
Abstract
The sonic or ultrasonic distance measuring device used for example to measure the filling level in a container comprises an electroacoustic transducer which operates alternately as transmission transducer for the transmission of sonic or ultrasonic pulses and as reception transducer for the reception of the reflected echo pulses. Connected to the transducer is a signal processing circuit which includes an amplifier with controllable gain and a threshold value discriminator. A gain control circuit controls the gain of the amplifier during a predetermined period after the start of each transmission pulse in accordance with a stored function which is fixed in accordance with the dying-down behaviour of the transducer so that the electrical signals originating from the dying-down of the transducer after amplification are smaller than the threshold value of the threshold value discriminator but are as close as possible to said threshold value. As a result the evaluation of echo pulses which occur during the dying-down of the transducer is possible.