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. 25, 1991
Filed:
Jun. 27, 1990
Alan S Drucker, DeWitt, NY (US);
Carrier Corporation, Syracuse, NY (US);
Abstract
A refrigerant expansion device for use in a refrigeration system includes a body having a flow passage extending therethrough. A piston having a flow metering port therethrough is moveably mounted within the flow passage. A flow metering rod is supported within the housing and extends through the flow metering port. The flow metering rod and the flow metering port cooperate to define a flow metering passage between them. The flow metering rod is configured so that the cross sectional area of the metering passage varies relative to the axial position of the piston with respect to the rod. The piston is spring biased and the piston moves relative to the rod as a function of the pressure differential across the piston. The cross sectional area of the flow metering rod is configured to define a defrost metering zone which cooperates with the metering port to provide a defrost flow metering passage, at pressure differentials lower than the normal pressure differential for cooling operation of a system in which the device is to be installed. The defrost metering passage is substantially larger than the flow metering passage required for normal cooling operation of the refrigeration system.