DE1598138A1 - Device for measuring the concentration of flowing gaseous suspensions, especially soot-containing exhaust gases from internal combustion engines - Google Patents

Description

R. no. 8718
Su / Ke 9/23/1966

Attachment to
Patent and
Use atnustQrhilf sanroe ldung

ROBERT BOSCH OMBH, Stuttgart W, Breitscheidstrasse

Device for measuring the concentration of flowing gaseous suspensions, in particular soot-containing exhaust gases from internal combustion engines

The invention relates to a device for »measuring the concentration of flowing gaseous suspensions, in particular dimensionally stable exhaust gases from internal combustion engines, in which the exhaust gas * is penetrated by a light beam perpendicular to its flow direction in a measuring tube and the light scattered by the suspension in one direction Light »receiver (FotoielX ·) fotoelectrleel * is measured (βIehe German patent specification 969 449).

009843 / 0A90 - 2 «

BATH ORIGINAL

Robert Bosch GmbH R. No. 87I8

Stuttgart September 23, 1966 3

For each scattered light measurement, the one measured by the light receiver must be used Scattered light size with a guide value, e.g. the light source itself, be matched. The amount of scattered light decreases linearly with increasing concentration of the suspension. But since every stray light a light absorption is superimposed "the old increasing concentration of the suspension is not linear" but increases logarithmically, the value measured by the light receiver must be corrected, if a linear reading ratio is desired. In order to compare the luminous intensity of the direct light source with that of the To make scattered light comparable, is in a known turbidity measuring device (see German patent specification 1 147 * K) 4) in the the comparison measurement by means of a switchover cover over various Plane glass panels direct light beam to the light receiver a gray wedge and a dark screen each arranged to be adjustable? This device is, in addition to the fact that the absorption error in This version is difficult to correct, time-consuming, expensive and relatively impractical because of sensitivity.

The invention is based on the object of a handy, simple To create a measuring device, in particular for the emission test of vehicles, in which the fetal absorption is automatically corrected.

According to the invention, this object is achieved in that the light receiver is carried by a tube which delimits its field of view the T-shaped into a muff that is rotatable around the nozzle Passes over and its axis against the axis of the light beam in tiner pivotable plane lying perpendicular to the axis of the suspension stream is, whereby three radial openings (diaphragms) present in the measuring tube can be opened through the sleeve for the passage of light, by dental in a manner known per se, two in the axis of the light beam, and the axis of the third opening at right angles forms the axis of the light beam. ■ · "'

In this case, the comparison light beam is also passed through the suspension, which then, in comparison with the light from the beam, trsM

009843/0400 ßAD original

Robert Bosch GaH R. No. 8718

Stuttgart September 23, 1960 8u / Ke

for each new concentration of the suspension to be measured in comparison the absorption remains without influence.

According to a further embodiment of the invention, the radial Openings (diaphragms) kept so small that the concentration in a core section of the duspensionstrocss is enjoyed.

An exemplary embodiment of the invention is shown in the drawing and will be described as follows. It show t

Flg. 1 shows a longitudinal section through a measuring device in the adjustment position,

Fig. 2 shows a cross-section getiKS the line U-II in Fig. 1 »where the measuring device is in the locked position and

Fig. 3 shows a section as in Fig. 2, in which the device in measuring position 1st.

Via a nozzle 1, which is arranged coaxially in a measuring tube 2, the suspension 3 to be tested for concentration flows into the Measuring tube. Via holes Λ the suspension flow breaks 3 Fresh * air into the measuring tube 2, which the Suspeneiotisstrom for cooling and Cleaning »especially in the measuring area» envelops like a envelope. *

A light beam generated by a lamp 5 and a condenser 6

7 traverses a slotted glass pane 8, the measuring tube 2 and the Suspension flow 3. In the measuring tube 2 are for this continuous jet Radial bores 9a, 9b and 9c are provided. Condenser 6, glass pane

8 and measuring tube 2 are firmly connected to one another via a carrier 10.

Iw measuring range is rotatable around the measuring tube 2 a sleeve 11 angeord, net, which merges into a tube 12 in a T-shape. In the sleeve 11 are outside of the mouth of the tube in the sleeve radial bores 13a and 13b

009843/0490. 4th

BATH ORIGINAL

Robert Bosch GmbH R. No. 8718 Stuttgart September 23, 1966 Sa / Ka

provided that when the sleeve 11 is turned, the radial bores 9a, 9b and 9c of the measuring tube 2b 'open or close. On that of the socket 11 opposite side, the tube 12 carries a light receiver 14. In tube 12 between light receiver 14 and measuring tube 2 is a protective glass pane 15 arranged. The light receiver 14 and the glass pane 15 are thus pivoted with the tube around the measuring tube.

In the adjustment position of the tube shown in FIG. 1, a straight passage for the light beam 7 is made possible by the radial bores 13a> 9 »and 9b as well as the tube 12. The variable measured by the light receiver 14, which already contains the partial absorption of the light beam by the suspension, thus serves as a benchmark for the measurement of this particular suspension. The correction of these dependent of the Konzentration.der suspension "absorption differences is carried out by changing the light intensity of the lamp 5» The light intensity of the lamp is thereby changed so long "to SiOH the pointer of a Meßwertanzeigegeräte not shown on the reference value ⁿ L of the scale ⁿ of the display device adjusts »

In the position of the tube 12 shown in Fig. 2, the path is of the light beam 7 blocked by the wall of the Haffe 11. In this Position is the light receiver 14 darkened so that the pointer of the measurement display device points to the zero point of the scale or can be adjusted to this.

In Flg. 3 let the tube 12 finally zellft in the measuring position. D # r Light beam 7 can be opened up through the radial bore 13b Hessrohr 2 penetrate where the light passes through the particles of the suspension is scattered. The radial openings 9a, 9c arranged at right angles to one another in the Hessrohr Id mask for the light receiver 14 part of the scattered light from the core of the Sue pens ions «troea 3 an ·· * Since in this measurement the light absorption is corrected by the adjustment in the tube division shown in FIG. 1 and dl Intensity of the scattered light of the number of particles in the suspension

009843/0490 ^AL

Robert Bosch GafcH R. No. 8718

Stuttgart September 23, 1966

is directly proportional, the concentration level of the suspension is linear and directly readable on the Keßwert display device.

Since, for example, dirty panes cause light absorption in the beam path cause is an additional advantage of this design, daö the same glass panes 8 and 15 are penetrated by the light in the individual tube positions. Absorption errors caused by contamination of the panes are eliminated.

BATH ORIGINAL

009843/0490

Claims (1)

Robert Bosch OnbH B. No. 8718 Stuttgart £ 23.9.1966 Expectations 1. Device for measuring the concentration of flowing gaseous suspensions, especially soot- containing exhaust gases from internal combustion engines, in which the exhaust gases are penetrated by a light beam perpendicular to their direction of flow in an emission tube and the light is scattered by the suspension in one direction. is measured photoelectrically, characterized in that the light receiver (14) is carried by a tube (12) limiting its field of view, the T-shaped In «ine among other things the measuring tube (2) rotatably arranged tube (11) and its axis against the The axis of the light beam (7) can be pivoted in a plane lying perpendicular to the axis of the sub-surface (3), with three radial openings (diaphragms) (9a, 9b) being provided through the sleeve (11) for the passage of light. 9c) are controllable, of which Ia two (9a, 9b) are in a known manner in the axis of the light beam (7), and the axis of the third. Opening (9o) elm η right angle alt the Aohae of the light beam · (7) forms. 2. Device according to Aaspruoh 1, characterized in that the radUUn Offtumfatt (Bit * · **) (9 · »9o)» o is kept small * fi> da · dl · concentration la as · »Keroauseefcaitt de« Suspem Um? » stroae geasf 00S343 / 3490 Robart BoBch GiöbH R. -No. 8 part 8 Stuttgart ^ 23 9.1966 Su / Ke . Device according to Claim 1 or 2, characterized in that it is marked, that the » the glass (15) protecting the light receiver (14) ralt dem ^ ubuB (12) -swiveled. 4. Device according to one of the preceding claims, characterized characterized in that the Suspenalonsstron (3) Iber a coaxial 3ua measuring tube (2) arranged nozzle (1) enters this and by entrainment of an optically empty medium, in particular fresh air, ie measuring tube (2) in a manner known per se. Suspension flow (3) Ia! TeO area cooling the meter (?) and cleansing * »Shell created. BATH ORIGINAL 009843/04 90 Blank page