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:
Sep. 13, 1994
Filed:
Apr. 01, 1992
Denis Y Yerlikaya, Des Peres, MO (US);
Randall J Krohn, Ballwin, MO (US);
Clarence L Walker, Webster Groves, MO (US);
Michael J Wilhelm, Rolla, MO (US);
Curtis D Kinghorn, Ferguson, MO (US);
Sherwood Medical Company, St. Louis, MO (US);
Abstract
A drop detector circuit and method are provided for a drop detector of the type including a drop chamber and an electro-optical sensor. A detector detects drops passing through the drop detector in an optical sensing path between the detector and at least one light source. In response to the detection of a drop passing through the optical path, the detector produces an output signal. A capacitor is connected between the detector and an amplifier to block the DC component of the output signal. After amplification, the signal is passed through a low pass filter to further block signals caused by undesirable factors. The cutoff frequency of the low pass filter is controlled by a microprocessor that controls the pump that pumps liquid from the drop chamber. The detector and light source or sources are arranged to detect drops falling in the drop chamber at virtually any angle and in virtually any ambient light condition.