Method and apparatus for servicing automotive refrigeration systems

摘要

A method and apparatus for determining refrigerant density and mass flow rate, and for pressurizing a refrigerant recovery tank while the refrigeration system is being recharged. The mass of a flowing refrigerant is automatically continually determined by reliable static means in a controlled recharging process. Flow-dependent pressure, such as the pressure drop across the orifice, and temperature data are taken from the recharging system and are connected to a data processor which uses the pressure and temperature data to determine the refrigerant density and the mass of the flowing refrigerant that has been used. The pressure of a source of recharging refrigerant can be maintained by withdrawing and heating liquid refrigerant and returning the resulting superheated vapor directly to the source of recharging refrigerant, and recharging operations can proceed during such pressure maintenance.