Patent ID: 7707844
Filing Date: 2010-05-04
Classification: F25B

Abstract:
1. A thermostatic expansion valve for controlling fluid flow comprising: an inlet, an outlet, and a first valve element disposed within a first valve opening between the inlet and outlet; a movable diaphragm having a first side in communication with a pressurized fluid external to the thermostatic expansion valve and a second side in communication with the outlet, the diaphragm being movable relative to a neutral position in response to changes in pressure between the outlet fluid pressure and the external fluid pressure, wherein the movement of the diaphragm controls the first valve element to regulate the fluid flow rate through the valve; and a second valve element disposed within a second valve opening between the inlet and the outlet, wherein the second valve element is coupled with the diaphragm, such that the second valve element is configured to be moved by the diaphragm away from the second valve opening for permitting fluid flow from the inlet through the second valve opening and a bypass passageway to the outlet; wherein the diaphragm is configured to respond to a force against the first side of the diaphragm that is less than the force against the second side by moving the first valve element to a closed position against the first valve opening and moving the second valve element away from the second valve opening so as to restrict fluid flow through the first valve opening to the outlet and permit fluid flow through the second valve opening to the outlet.