JPS6027953Y2 - Neumatic light detector - Google Patents

Description

[Detailed Description of the Invention] The present invention is a pneumatic light beam detector particularly for a two-beam infrared gas analyzer, in which a modulator cuts a light beam into two optical paths with opposite phases, and The detector has two consecutive upper and lower detection chambers filled with a light-absorbing gas and provided with a light-transmissive window in the l block, and with respect to these detection chambers, there is a rain detection chamber located in the center between the rain detection chambers. Connected is another chamber having an internal diaphragm capacitor, the diaphragm capacitor being of the type that divides the diaphragm capacitor chamber into two chamber sections and converts the pressure difference between the chamber sections into an electrical signal.

It is an object of the present invention to improve a light beam detector of the above type with respect to its measurement properties, in particular the occurrence of signal disturbances due to the mechanical vibrations and shocks that act, which lead to vibrations of the gas mass and the capacitor diaphragm, and the zero point. The aim was to improve stability.

This problem is solved according to the invention by the rain detection chambers 7, 9 and the subsequent detection chambers 8, which are initially loaded by the light beam in each beam path.
10 each corresponds to chamber section 13 or 1 of the diaphragm condenser chamber.
Is it connected to one of 6 and all rooms or room divisions? , 8, 9. 10. 13. 16 and gas conduits 14, 15
, 17, 18 are the centroids of the gas mass in the chamber section 13 of the detection chambers 7, 9 and the diaphragm condenser chamber 11 connected thereto, which are first loaded by the beam, and the detection chamber 8, which is loaded last by the beam. 10 and the centers of gravity of the chamber sections 16 of the diaphragm condenser chamber 11 connected thereto are designed and arranged so that they overlap.

The invention will now be described with reference to the illustrated embodiment.

1 shows a light beam detector according to the invention for a two-beam infrared gas analyzer.

The light beams of the two infrared emitters 1 and 2 guided in parallel optical paths are interrupted in antiphase by a rotatable beam interrupter 3.

One optical path is provided with a measuring cell 4 through which the sample gas passes, and the other optical path is provided with a reference cell 5 filled with reference gas or evacuated.

The light detector indicated at 6 has detection chambers 7 and 8 which are successive one above the other for the radiation rays emitted from the measuring cell 4 and one after the other detection chambers 9 and 8 which are successive one above the other for the rays emanated from the reference cell 5. 10 from the metal block.

All chambers, cells and radiators are equipped with light-transparent windows that hermetically seal.

In the center between the detectors there is another chamber 11 in the metal box divided by a capacitor diaphragm 12.

The upper section 13 of the diaphragm condenser chamber has gas conduits 14 and 1
5 to the detection chambers 7 and 9, and the lower section 16 of the diaphragm condenser chamber to the detection chambers 8 and 10 via gas lines 17 and 18.

A fixed electrode plate 19 is arranged opposite the capacitor diaphragm 12 .

The pressure fluctuations caused by light absorption in the gas-filled detector are converted into electrical signals by the diaphragm capacitor after the leads 20 and 21 are energized.

This signal is connected to chamber sections 13 and 16 of diaphragm condenser chamber 11.
proportional to the pressure difference between

Detectors 8 and 9 are of conical design in a known manner for radiation physics reasons.

All chambers or chamber sections and gas conduits have a center of gravity of the gas mass in the chamber section 13 of the detection chambers 7, 9 and the diaphragm condenser chamber 11 connected thereto, which are first loaded by the beam of light, and which are loaded last by the beam of light. The center of gravity of the detection chambers 8, 10 and the chamber section 16 of the diaphragm condenser chamber 11 connected thereto overlaps with each other.

Advantageously, the overall center of gravity lies in a plane of symmetry of the detector which is equally spaced from the detector and which halves the diaphragm capacitor chamber.

This results in a distant relative of the advantageous measuring effects mentioned at the outset.

[Brief explanation of drawings]

The drawing is a schematic illustration of a light beam detector according to the present invention for a two-beam infrared gas analyzer. 7, 8.9. 10...Detection chamber, 13.16...Room division, 11...Diaphragm condenser chamber, 14, 15, 17
．． 18...Gas conduit.

Claims (1)

[Scope of utility model registration request] A pneumatic light detector, in which a modulator cuts the light beam into two optical paths in antiphase, and the detector for each optical path is filled in one block with a light-absorbing gas and has a light-transparent window. It has two detection chambers extending above and below the rain detection chambers, and connected to these detection chambers is another chamber located in the center between the rain detection chambers and having a diaphragm capacitor inside. In those types in which the capacitor divides the diaphragm capacitor chamber into two chamber sections and converts the pressure difference between the chamber sections into an electrical signal, the rain detection chambers 7, 9 and 9, which are first loaded by the light beam in each optical path, Subsequent detection chamber 8,1
0 is the chamber section 13 or 16 of the diaphragm condenser chamber.
Is it connected to one of the rooms and all rooms or room divisions?
, 8, 9, 10. 13, 16 and gas conduits 14, 15.
17° 18 is the detection chamber 7 which is first loaded by the light beam.
．． 9 and the center of gravity of the gas mass in the chamber section 13 of the diaphragm condenser chamber 11 connected thereto, and the center of gravity of the detection chambers 8, 10 and the chamber section 16 of the diaphragm condenser chamber 11 connected thereto, which are finally loaded by the light beam. A pneumatic light beam detector designed and arranged so that the two overlap with each other.