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:
Feb. 22, 1977
Filed:
Oct. 31, 1975
Kenneth C Tregillus, Yellow Springs, OH (US);
Vernay Laboratories, Inc., Yellow Springs, OH (US);
Abstract
An emitter for use in drip irrigation systems which is both self-purging and pressure responsive to provide substantially constant flow rates with varying inlet pressures. The emitter includes a flow path which consists of a series of interconnected openings in each of which is positioned a valve including a valve lip which extends across the opening in which it is located and is directed in an upstream direction so that as the pressure drop across any one valve increases, the effective area of the flow path at that valve will decrease to maintain a substantially constant flow rate. When the pressure drop at a particular valve increases above a predetermined amount, as when a particle of dirt or other foreign substance clogs the valve, the valve lip travels over center and allows the clogging particle to pass, thereby purging that particular valve and permitting it to return to its normal operating position. The emitter is preferably formed with a resilient central body portion and relatively rigid outer cover plates. In one embodiment the flow path openings and interconnecting passages are formed in the central body portion. In a second embodiment the openings and interconnecting passages are formed in the cover plates and the central body portion comprises a sheet of resilient material having tongues struck therefrom which project into the flow path defined by the contoured cover plates when the emitter components are assembled.