Apparatus for producing a calibration sample for analytical instrumentation

Claim 1

Apparatus for producing a calibration gas mixture of known composition from a plurality of component gases separately introduced therein and blended together for use with analytical instrumentation, including: a pressure vessel forming a gas mixing chamber of mass large relative to the mass of the gaseous contents introduced therein to provide a sufficient heat sink to hold the gas temperature substantially stable during the blending of the gases; a stirring element movably disposed in said gas mixing chamber for homogenizing the mixture of gases introduced into, and retained within, said chamber while the gases are homogenized; exhaust valve means operatively communicated with said chamber for controlling flow from said gas mixing chamber; vacuum means communicating with said exhaust valve means of said gas mixing chamber for substantially exhausting said gas mixing chamber when desired; pressure transducer means for measuring the absolute pressure of the gases in said mixing chamber and producing a usable output signal in response to the absolute pressure present in said mixing chamber; pressure indicator means operatively connected with said pressure transducer means for displaying the absolute pressure measured by said pressure transducer means; and a plurality of inlet valves, each of which is in fluid communication with said mixing chamber and with a supply of a component gas of the gas mixture for controlling the introduction of the desired component gases into said mixing chamber.