Patent attributes
A fluid injection device (10) for injecting a dispensible fluid material (28), e.g., a liquid sealant, into refrigerant lines of an operating air conditioning or refrigeration system or the like, includes a tube (12) having at its outlet end a fluid outlet valve (18) is closed by a valved plug (24) to provide therebetween an airlock chamber (42) containing a dried inert gas which prevents reaction, e.g., polymerization, of any liquid sealant which has leaked past the fluid outlet valve (18) prior to use of the device. The device (10) is used by removing the valve plug (24) just prior to use and connecting the outlet valve (18) to a low pressure zone of the system and then connecting an inlet closure member (14) to a high pressure zone of the system while the system is in operation. A method of making the device includes displacing air from the device with the inert gas and then introducing the material 18 into the tube.
