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:
Nov. 20, 2001
Filed:
Sep. 01, 2000
Donald E. Wortman, Rockville, MD (US);
John D. Bruno, Bowie, MD (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
A valve-less fluid control circuit for controlling rhythmic action devices, such as circulatory assist devices. The fluid control circuit has a plurality of pressure sensitive fluid oscillators for circulating a fluid. Each fluid oscillator includes a capacitance chamber unit for peristaltic pumping of fluid after being filled via an input conduit and a resistance conduit. A first control conduit provides an outlet of fluid from the capacitance unit during peristaltic pumping, and when the pressure of the fluid in the first control conduit reaches a certain level relative to the pressure of fluid in the input conduit, the fluid is directed through an interactive region and exits the first fluid oscillator through an exhaust conduit. A coupling unit couples the output of the first fluid oscillator to the input conduit of the successive fluid oscillator, so that the expansion and contraction of the capacitance chambers occurs successively without the need for valves and/or complicated control circuitry, such as solenoids and cams. A return conduit at the last fluid oscillator returns the fluid to a second control conduit of the first fluid oscillator to refill the first capacitance chamber.