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:
Oct. 12, 1993
Filed:
Mar. 31, 1992
Thomas Grass, St. Louis County, MO (US);
Robert W Haul, St. Louis County, MO (US);
Emerson Electric Co., St. Louis, MO (US);
Abstract
A reversible flow thermal expansion valve for use in a heat system is disclosed wherein the thermal expansion valve includes a valve body having a flowpath therethrough with an inlet and outlet, an expansion port within the flowpath, and an expansion valve to open and close the expansion port. An internal by-pass flow path by-passes the expansion port for reverse flow through the expansion valve. A check valve in the by-pass flow path prevents refrigerant from by-passing the expansion port during regular, forward flow through the expansion valve. The check valve has a spring to bias the check valve normally closed, and a bypass port communicating between a check valve guide path chamber and a check valve outlet in order to relieve pressure in the guide path chamber and increase the flow rate through the check valve.