Patent ID: 7726176
Filing Date: 2010-06-01
Classification: G01N

Abstract:
1. A paramagnetic gas analyzer with a housing, the paramagnetic gas analyzer comprising: an electromagnet that has spaced opposing magnetic poles forming an air gap with a magnetic field therebetween; a power source for supplying an electrical current to said electromagnet; a sample gas conduit and a reference gas conduit opening into said air gap, said sample gas conduit carrying a gas mixture to be analyzed, and said reference gas conduit carrying a reference gas having a known concentration of a gas; an exit conduit communicating with said air gap for removing the gas mixture and reference gases from said air gap with the magnetic field; two pressure detecting microphones positioned symmetrically to each other, one each connected, respectively, to said sample gas conduit and to said reference gas conduit for sensing gas pressures in the respective conduits, and giving respective electrical pressure signals; and electronics connected to said microphones, said electronics for receiving said electrical pressure signals to form an analyzer output signal, wherein each of said pressure detecting microphones comprise a microphonic membrane independent from the microphonic membrane of the other pressure detecting microphone, and that has a pressure surface open to one of said sample gas conduit and said reference gas conduit, wherein said pressure detecting microphones are fixed together in manner that causes similar movement of both microphones under a mechanical shock, wherein said microphonic membranes are movable as responses to pressure changes in said sample gas conduit and in said reference gas conduit respectively, and electrical outputs providing signals proportional to gas pressures in the sample gas and reference gas conduits, and wherein said microphonic membranes are parallel to each other so that said pressure surfaces oppose each other and are directed to the same direciton, or to the opposite directions in response to gas pressure in the gas conduits.