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. 05, 1991
Filed:
Dec. 28, 1989
Robert J LeFevre, Bethlehem, PA (US);
Other;
Abstract
A portable drug delivery device for delivering a drug in liquid or fluid form at a constant and self-regulated rate to a patient comprises a syringe having spring loaded piston reciprocal in a cylinder having a reverse taper to pressurize the drug to be dispensed. The reverse taper on the cylinder results in decreasing friction on the piston as the piston moves in the cylinder during a dispensing cycle, and is designed to compensate for the decreasing force exerted on the piston by the expanding spring. A length of tubing connected to the syringe conveys the drug to a needle or other device for administering the drug to a patient, and a restrictor in the length of tubing impedes flow of the drug to achieve a desired flow rate. The restrictor may be sized to achieve any desired flow rate, and in a preferred form of the invention comprises a laser-burned hole in a fitting attached to the outlet end of the length of tubing.