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:
Sep. 17, 1996
Filed:
Aug. 30, 1994
Walter W Powell, Sugar Land, TX (US);
Milton N Anderson, Jr, Houston, TX (US);
Louis R Castaneda, Houston, TX (US);
Aciel Martin, Houston, TX (US);
Groth Corporation, Houston, TX (US);
Abstract
A safety relief valve (10) having a main valve member (22) in a normally closed seated position has a diaphragm actuator (24) with a dome chamber (34) adjacent the outer side of the diaphragm (26). A pilot valve (28) is in fluid communication with the dome chamber (34) through a dome line (35) for controlling the opening and closing of the main valve member (22). An underdome chamber (40) on the inner side of the diaphragm (26) has an underdome line 44 extending to an underdome control valve (42) for controlling fluid communication to underdome chamber (40) from the inlet (18). An inlet line (48) extends from the inlet (18) to the underdome control valve (42). When the set pressure of the pilot valve (28) is reached, inlet fluid pressure on the inner side of the diaphragm (26) increases while dome pressure in the dome chamber (34) decreases. Simultaneously, an increase in fluid inlet pressure at inlet (18) actuates underdome control valve (42) to provide direct fluid communication between inlet (18) and underdome chamber (40) to boost the opening of main valve member (22). One embodiment of the invention shown in FIGS. 6 and 7 utilizes a non-pilot operated relief valve member (10C) in which a weight (29C) urges the main valve member (22C) into closed position. An underdome control valve (42C) includes a weight (65C) urging the underdome control valve member (67C) into a seated position.