公开(公告)号：US5060505A

公开(公告)日：1991-10-29

申请号：US406041

申请日：1989-09-12

Applicant: Edward L. Tury ,  Keith Kaste ,  Ross E. Johnson ,  David O. Danielson

Inventor： Edward L. Tury ,  Keith Kaste ,  Ross E. Johnson ,  David O. Danielson

IPC: G01N21/27 ,  G01N21/31 ,  G01N21/35

CPC classification number: G01N21/3504 ,  G01N21/274 ,  G01N2021/3129 ,  G01N2021/3174 ,  G01N2201/1285

Abstract: A non-dispersive infrared gas analyzer especially adapted for measuring the concentrations of HC, CO and CO.sub.2 in a vehicle exhaust includes a sample chamber for holding a sample gas, a radiation emitter for directing a beam through the chamber and a detector for indicating the amount of radiation absorbed. A plurality of filters, each of which transmit radiation at an absorption band of a gas component to be detected, are alternatingly positioned in the radiation path to produce a time-multiplexed signal having concentration information for all gases. A calibration assembly is provided which includes a plurality of calibration cells selectively positionable in the radiation path in order to provide an internal calibration standard for two-point calibration of each gas channel. The cells contain one or more of the gas components to be measured at concentrations and pressures predetermined to compensate for the difference in optical path length between the calibration cells and the sample chamber. A technique is provided for characterizing the calibration cells in situ after a conventional calibration, using bottled calibration gas, is performed.

公开(公告)号：US5024526A

公开(公告)日：1991-06-18

申请号：US333392

申请日：1989-04-05

Applicant: Heribert von Redwitz

Inventor： Heribert von Redwitz

IPC: G01J5/42 ,  G01N21/51 ,  G01N21/53

CPC classification number: G01N21/53 ,  G01J5/42 ,  G01N2021/516 ,  G01N2021/6469 ,  G01N21/538 ,  G01N2201/1285

Abstract: A measuring instrument for simultaneous in situ determination of the spectral scatting and absorption coefficient, which can also be called an extinction meter, has a modulated light source and an optical system encompassing the hemisphere; the optical system has a multiply folded ray path with a focal point in the volume to be measured, and through this system the measurement signal is projected to detectors. The scattering measurement signals, which are maximally enlarged in this way, are then separated from those for the absorption. The extinction meter also has not only an integrating nephelometer for monitoring purposes but also a transmission meter for low transmission factors. Because of the small three-dimensional size and the streamlined shape of the measuring portion of the extinction meter, the extinction meter can be carried in aircraft and surface vehicles. Because of the disposition of the optical system, the error in the measurement values is negligible, in comparison with other instruments with which only the scattering coefficient can be determined. Moreover, the calibration value during a measurement phase can be determined both automatically and manually. Contamination of the instrument with gas to be measured is reduced, by the stabilization of a turbulence ring by means of baffles. Moreover, interference with the flowing aerosol on the part of the instrument is largely eliminated via a hoop-like hood functioning like a wing-tip slot.

Abstract translation: 用于同时原位测定光谱散射和吸收系数的测量仪器（也称为消光计）具有调制光源和包围半球的光学系统; 该光学系统具有在要测量的体积中具有焦点的多重折叠的光线路径，并且通过该系统将测量信号投影到检测器。 然后以这种方式最大化地扩散的散射测量信号与用于吸收的散射测量信号分开。 灭火表不仅具有用于监测目的的积分浊度计，而且还具有低传输系数的传输仪表。 由于消光表的测量部分具有小的三维尺寸和流线型的形状，所以消光计可以被携带在飞机和地面车辆中。 由于光学系统的配置，与其中只能确定散射系数的其他仪器相比，测量值的误差可以忽略不计。 此外，可以自动和手动地确定测量阶段期间的校准值。 通过挡板稳定湍流环，仪器与待测气体的污染减少。 此外，通过像翼尖槽一样的环形罩大大消除了对仪器部分流动的气溶胶的干扰。