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, 1998
Filed:
Jun. 10, 1994
Joseph B Seale, Gorham, ME (US);
P.D. Coop, Inc., Bedford, NH (US);
Abstract
An electromechanical transducer drives a resonator plate, which develops oscillating pressure in a contacting liquid. A high-speed check valve rectifies the pressure oscillations, causing pumping. On the driver side of the valve, the high inertial flow impedance in a narrow passageway confines oscillating pressure while admitting non-oscillating fluid flow. On the valve side opposite the driver, a volumetric compliance element decouples the inertia of the fluid passageway to permit fast acceleration and deceleration of fluid pulsing through the valve. A high-speed passive check valve consists of a thin-section o-ring covering a circular slot, with circumferential tension setting the forward bias pressure. Pump frequencies above one kilohertz and microliter stroke volumes are practical. Electrical impedance measurements on the pump indicate fluid volume in the pump. A coupling of two pumps in series and an alternation of pumping and volume measurement operations in the coupled pumps leads to volumetric metering of fluid.