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:
Aug. 27, 2002
Filed:
Nov. 17, 2000
David Brian Chamberlain, Manchester, NH (US);
MKS Instruments, Inc., Andover, MA (US);
Abstract
A valve assembly including a body defining a passageway having a longitudinal axis, a rotatable shaft extending into the passageway, generally perpendicular to the axis of the passageway, and a flapper secured to the shaft within the passageway and movable upon rotation of the shaft between an opened position and a closed position. The flapper includes a groove in an outer circumference, and a seal is received in the groove. The seal has an outer circumference greater than the outer circumference of the flapper so the entire outer circumference of the seal contacts a wall of the passageway when the flapper is moved to the closed position. The seal also has an inner circumference greater than an inner circumference of the groove of the flapper such that an enclosed space is defined between the seal and the groove. An aperture provides fluid communication between the enclosed space and the passageway.