公开(公告)号：US4687934A

公开(公告)日：1987-08-18

申请号：US818342

申请日：1986-01-10

Applicant: Robert E. Passaro ,  Raymond E. Rogers ,  Craig J. Griffith

Inventor： Robert E. Passaro ,  Raymond E. Rogers ,  Craig J. Griffith

IPC: G01J1/44 ,  G01N21/27 ,  G01N21/31 ,  G01N21/35 ,  G01J1/00 ,  G01D18/00

CPC classification number: G01N21/274 ,  G01N2021/3159 ,  G01N2021/3166 ,  G01N21/3504 ,  G01N2201/126 ,  G01N2201/1273 ,  G01N2201/12769

Abstract: Automatic zeroing apparatus zeroes an infrared gas analyzer automatically upon the occurrence of preselected conditions to indicate zero in the absence of absorption of infrared radiation by a gas mixture being analyzed. The gas analyzer has a sample cell for containing a gas mixture to be analyzed. Infrared radiation directed through the sample cell is detected at a preselected wavelength to produce a detection signal. A signal processor outputs a signal systematically related to the difference between the detection signal and a reference signal. For zeroing the sample cell is filled with gas substantially nonabsorbent of infrared radiation at the respective characteristic wavelength. A comparator produces an error signal when the output signal differs from zero. A gain control automatically controls the signal level of the detection signal to reduce the output signal substantially to zero with the nonabsorbent gas filling the sample cell. The preselected conditions may include the passage of a predetermined time and a temperature drift beyond a predetermined limit.

Abstract translation: 自动归零装置在发生预选条件时自动归零红外气体分析仪，以便在被正在分析的气体混合物不吸收红外辐射时指示为零。 气体分析仪具有用于容纳要分析的气体混合物的样品池。 以预选的波长检测引导通过样品池的红外辐射，以产生检测信号。 信号处理器输出与检测信号和参考信号之间的差异系统地相关的信号。 为了归零，样品池中填充有相应特征波长的基本上不吸收红外辐射的气体。 当输出信号与零不同时，比较器产生一个误差信号。 增益控制器自动控制检测信号的信号电平，使填充样品池的非吸收气体将输出信号基本上降至零。 预选条件可以包括经过预定时间和温度漂移超出预定极限。