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:
Jul. 30, 1996
Filed:
Jan. 31, 1994
Stanley A Mercado, Fremont, CA (US);
Mark M McPhee, Austin, TX (US);
Avtar S Nat, Fremont, CA (US);
Su I Yum, Los Altos, CA (US);
Scott A Bura, San Jose, CA (US);
ALZA Corporation, Palo Alto, CA (US);
Abstract
The present invention provides a gas generating engine for driving a beneficial agent dispensing device. The engine comprising (a) a solid composition comprising an acidic compound or a basic compound, or a combination thereof, and (b) a means for maintaining substantially constant the surface area of the solid composition exposed to a reservoir fluid comprising water, or water and an acidic compound, or water and a basic compound, wherein in operation, the solid composition is exposed to the reservoir fluid which dissolves the solid composition and causes it to generate a gas, the gas being a driving fluid to dispense a beneficial agent. The present invention further provides a fluid driven dispensing device for delivering an agent into an environment of use, the device be driven by the gas generating engine.