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. 06, 2001
Filed:
Mar. 16, 1999
Alfred A. Frankenberg, Blount County, TN (US);
Robertshaw Controls Company, Richmond, VA (US);
Abstract
A bellows valve assembly installed in a fluid pathway includes a valve body, a bellows housing positioned adjacent the valve body, and a valve actuator. The valve body is equipped with an inlet, an outlet, a valve bore positioned between the inlet and the outlet, and a valve seat disposed between the inlet and the outlet. A valve closure element having a sealing surface is positioned in the valve bore and is engageable with the valve seat to restrict fluid flow through the valve bore. The valve closure element also has a valve stem that extends from the valve bore through the bellows housing. The valve stem has a lower portion characterized by a first average diameter and an upper portion characterized by a second average diameter that is at least 25% smaller than the first average diameter. The actuator is engageable with the upper portion of the valve stem to move the sealing surface relative to the valve seat. Further, a pressure-balanced bellows assembly is positioned in the bellows housing and has at least one section secured to the valve stem such that the bellows assembly surrounds a portion of said valve stem. The bellows assembly divides the bellows housing into a first chamber defined inside of the bellows assembly and a second chamber defined outside of the bellows assembly. A first passageway is provided to extend between the first chamber and a location in the fluid pathway downstream of the valve seat so as to communicate the fluid pressure downstream of the valve seat to the first chamber. Further, a second fluid passageway is provided to extend between the second chamber and a location in the fluid pathway upstream of the valve seat so as to communicate the fluid pressure upstream of the valve seat to the second chamber.