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:
May. 30, 2000
Filed:
May. 19, 1998
Peter Vari, Richboro, PA (US);
Other;
Abstract
In an automatic on-off sprinkler, water enters an inlet and passes through a hollow interior region to the outlet. A reciprocating member in the hollow region normally blocks the outlet when water entering a narrow passageway fills a central chamber above the reciprocating member. A large gap between the hollow region ID and the reciprocating member OD permits friction-free movement of the reciprocating member. A flexible, water-tight diaphragm seals the central region, preventing liquid entering the narrow passageway from communicating with a lower region from passing to the outlet. A sensor detects an emergency condition, unsealing a control opening larger than the narrow passageway, allowing liquid to rapidly escape through the unsealed control, dropping the pressure in the central region, whereby a pressure imbalance lifts the reciprocating member closing the outlet. When the control opening is resealed, liquid pressure in the central region sealed by the water-tight membrane increases. The internal pressure urges the reciprocating member to the closed position when the central region is filled, which condition is maintained during normal temperature conditions. The flexible water-tight diaphragm eliminates the need for O-ring seals which create undesirable frictional forces. The reciprocating member may be spherical or cylindrical and may be formed of a suitable metal or other material. A light closing spring may be provided to normally urge the spool to the closed position. The control valve may be used to control two or more conventional sprinkler heads.