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:
Jun. 20, 1978
Filed:
Aug. 26, 1976
Applicant:
Inventor:
Ernest W Schumacher, Desoto, TX (US);
Assignee:
Virginia Chemicals Inc., Portsmouth, VA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05D / ;
U.S. Cl.
CPC ...
236 / ; 62225 ; 13750518 ;
Abstract
A thermostatic expansion valve for large-capacity refrigeration systems has a pressure-balanced valve pin and no means of communicating inlet pressures to the underside of the diaphragm. The valve pin has a coaxial bore, a pair of end faces, a pair of cylindrical portions fitting slideably in a feed bore leading to an outlet chamber, a reduced stem portion of small diameter between the pair of cylindrical portions, and a pair of shoulders connecting the reduced stem portion to the pair of cylindrical portions. The shoulders are exposed to the same pressure so that the valve pin is balanced.