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:
Dec. 24, 2002
Filed:
Aug. 06, 2001
Richard R. Watson, Missouri City, TX (US);
Gilmore Valve Co., Ltd., Houston, TX (US);
Abstract
A hydraulic latching spool valve has at movable piston and valve cage defining two seats. In the valve cage, a moveable piston is operable to move the valve into open and closed positions. A spring positioned in a pilot close chamber urges the piston to close. A pulse of fluid pressure at a pilot open chamber causes the piston to open. A latching chamber is formed on the interior of the piston, the latching chamber being exposed to supply pressure when the piston is in the open position. Accordingly, in the open position, supply fluid in the latching chamber generates sufficient latching force to overcome opposing forces generated by the sprig. The supply pressure holds the piston in the open position until a pulse of fluid pressure is applied to the pilot close chamber, thereby causing the valve to close.