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:
Mar. 27, 1979
Filed:
Nov. 22, 1976
Frederick L Maltby, Jenkintown, PA (US);
Jonathan Kramer, Warminster, PA (US);
Kenneth M Loewenstern, Warminster, PA (US);
Drexelbrook Controls, Inc., Horsham, PA (US);
Abstract
A two-wire transmitter includes an admittance sensing probe adapted to sense the conditions and corresponding admittance of materials. The probe is coupled into an admittance responsive network which generates an admittance signal representing the condition of materials. The output current from the transmitter is varied in response to the admittance signal. In one embodiment of the invention, the admittance responsive network comprises a variable frequency oscillator whose frequency varies with the admittance of the materials. In another embodiment, the admittance responsive network comprises a ramp generator with a frequency which varies with the admittance of the materials. In another embodiment, the admittance responsive network comprises a bridge whose balance changes in response to the admittance of the materials.