GB1589333A - Fluid-flow pollutant monitoring systems - Google Patents
Fluid-flow pollutant monitoring systems Download PDFInfo
- Publication number
- GB1589333A GB1589333A GB5024277A GB5024277A GB1589333A GB 1589333 A GB1589333 A GB 1589333A GB 5024277 A GB5024277 A GB 5024277A GB 5024277 A GB5024277 A GB 5024277A GB 1589333 A GB1589333 A GB 1589333A
- Authority
- GB
- United Kingdom
- Prior art keywords
- hollow body
- light detector
- light
- light source
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000012544 monitoring process Methods 0.000 title claims description 12
- 239000003344 environmental pollutant Substances 0.000 title claims description 11
- 231100000719 pollutant Toxicity 0.000 title claims description 11
- 239000000523 sample Substances 0.000 claims abstract description 21
- 239000011521 glass Substances 0.000 claims abstract description 5
- 239000012530 fluid Substances 0.000 claims description 15
- 239000004020 conductor Substances 0.000 claims description 6
- 229910001218 Gallium arsenide Inorganic materials 0.000 claims description 4
- 230000001419 dependent effect Effects 0.000 claims description 3
- 238000003780 insertion Methods 0.000 claims description 2
- 230000037431 insertion Effects 0.000 claims description 2
- 239000002245 particle Substances 0.000 abstract description 15
- 229920001875 Ebonite Polymers 0.000 description 3
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000012806 monitoring device Methods 0.000 description 2
- 229910052711 selenium Inorganic materials 0.000 description 2
- 239000011669 selenium Substances 0.000 description 2
- 238000000149 argon plasma sintering Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G21/00—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
- G03G21/10—Collecting or recycling waste developer
- G03G21/105—Arrangements for conveying toner waste
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
- G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
- G03G15/1605—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support
- G03G15/161—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer using at least one intermediate support with means for handling the intermediate support, e.g. heating, cleaning, coating with a transfer agent
Landscapes
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Sustainable Development (AREA)
- Environmental & Geological Engineering (AREA)
- Dispersion Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
In order to monitor a gas flow for particles present therein, e.g. toner particles, a probe (SO) is arranged in the gas flow. The probe (SO) consists of a transparent hollow body (GL), e.g. a small glass tube, of a light source (LQ), which is arranged in the hollow body (GL) and illuminates it on that side of the wall on which the gas flow impinges on the hollow body, and of a photodetector (FO) which is arranged in the hollow body and receives the light reflected on the wall side. The particles contained in the gas flow are deposited on the wall side, resulting in a change in intensity of the reflected light. The photodetector emits a corresponding signal which is analysed by a threshold-value circuit. <IMAGE>
Description
(54) IMPROVEMENTS IN OR RELATING TO FLUID-FLOW POLLUTANT
MONITORING SYSTEMS
(71) We, SIEMENS AKTIENGESELLSCHAFT, a German Company of Berlin and Munich, German Federal Republic, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
The invention relates to fluid flow pollutant monitoring systems.
There are many different applications in which it is necessary to establish whether a fluid flow, e.g. an air flow, contains any discrete particles. This can be the case when a gas flow is being filtered in order to eliminate particles from the flow of gas. In the path of the gas following the filter it is possible to arrange a monitoring device which serves to check whether the filter is still operating satisfactorily.
One typical application is in a nonmechanical printer operating in accordance with the electrostatic principle. In such a printer, a charge image of the characters which are to be printed is produced in known manner on an intermediate carrier, e.g. a selenium drum. The charge image is developed with the aid of toner and is transferred in a reproduction station to a paper web.
However, following the making of a reproduction, some residual toner remains on the intermediate carrier, and this needs to be removed from the intermediate carrier in a cleansing device. For this purpose it is possible, for example, to use a brush which strips the toner from the intermediate carrier. The efficiency of this cleansing brush can be improved by use of a suction system which sucks toner out of the brush container, the suction system consisting of a closed circuit in which the toner sucked out of the cleansing brush container is then removed from the gas flow, in this case a flow of air, employing a filter arranged in the pipeline provided for the gas flow.
It is necessary to ensure that this filter is operating satisfactorily, as if this is not so, there is no longer any safeguard that the intermediate carrier, thus the selenium drum, is being cleansed satisfactorily, and the defect which has occurred must be investigated. This makes it desirable to arrange in the flow path after the filter a device which checks whether the filtered gas flow contains particles. A cleansing device operating in accordance with the above described principle, but without such a monitoring device, is disclosed in the United States
Patent Specification No. 3,190,198, for example.
One object of the present invention is to provide an improved device for monitoring fluid flow to detect any pollutant particles present therein.
The invention consists in a fluid flow pollutant monitoring system comprising a pipeline through which a fluid is flowing, a probe arranged to project into said pipeline, and having a light-permeable hollow body containing a light source positioned to illuminate that wall portion of the hollow body on which the said flow is incident, and also containing a light detector positioned within the hollow body to receive a component of any light reflected and/or scattered from this wall and so produce a signal proportional to the reflected and/or scattered light strength.
Advantageously the probe is arranged in a section of the pipeline where the internal wall surface or surfaces are blackened, so that any light which passes through the wall of the hollow body into the pipe becomes absorbed on a blackened surface and cannot be reflected back to reach the probe detector.
Preferably the probe is arranged in the pipeline at right angles to the direction of fluid flow.
As supply and signal conductors are required for the light source and the light detector and this must be conducted from the pipeline exterior to the interior of the probe advantageously at least one end of the probe projects from the pipeline, with an open end so that the required connection lines can be conducted without difficulty to the light source and the light detector.
The light source and the light detector may be arranged in a block, e.g. of hard rubber, the exact position of the light detect tor and of the light source relative to one another can be clearly determined. and furthermore the light source and the light detector can be easily exchanged. as it is then only necessary to remove one block from the hollow body or insert a replacc ment assembly thercin.
Expediently the light source is positioned at an angle to the light detector, and in this case the light detector is preferably arranged to be aligned with the flow and facing the oncoming fluid.
The signal from the light detector may be fed to a threshold value circuit, which analyses the signal from the light detector and emits an output signal when the signal from the light detector exceeds a specific threshold value. As the strength of the signal from the light detector is dependent upon how many particles in the gas flow become deposited upon the wall of the hollow body to form a light scattering or reflec tive coating thereon. the strength of the signal from the light detector is a measure of the number of particles still contained in the fluid flow. The threshold value circuit emits an output signal when the reflector formed by particle deposition on the probe wall reflects an excessive degree of light from the light source to the light detector.
The light source may consist of a GaAs luminescent diode. for example. The light detector may consist of a photo-transistor.
The hollow body may be a glass tube whose surface is bloomed.
lf the device is arranged at the rear of the filter in a cleansing device of an intermediate carrier in a non-mechanical printer. it is thus possible to automatically check whether the intermediate carrier is still being satisfactorily cleansed by the cleansing device.
The invention will now be described with reference to the drawings, in which:
Figure 1 schematically illustrates one exemplary embodiment of a probe arranged in a portion of a pipeline for fluid flow; and
Figure 2 is a block schematic circuit diagram of a threshold value circuit suitable for the analysis of the signal from the light detector.
In Figure 1, only a portion of a pipeline
LA for the gas flow in a non-mechanical printer is shown. Here gas is to flow in the direction indicated by arrows in the pipeline
LA, which forms art of a suction system by which the gas how, e.g. air. is sucked through the pipeline LA in the indicated direction. The internal surface of the pipeline LA is blackened in the region of a probe SO, and the pipeline can have any required cross-section.
The probe SO for monitoring the gas flow in respect of pollutant particles present therein is arranged in the pipeline LA at right angles to the gas flow. The probe is constructed from a hollow body GL, a light source LO and a light detector FO.
The hollow body GL can consist, for example, of a glass tube, but can also be constructed from any light-permeable synthetic resin matcrial. The hollow body cL can be arranged in the pipeline LA in such manner that it partially projects from the pipeline LA, and its end within the pipeline LA is closed, whereas the external end is open, to permit conductors DL to reach the light source LQ and the light detector FO, as indicated schematically in the drawing.
The light source LO consists of a GaAs luminescent diode. and the light detector
FO consists of a photo transistor in this embodiment. Both the light source LQ and the light detector FO are arranged in a block
HB, consisting in this example of hard rub ber, and serving to establish the relative position of the light source LQ with respect to the light detector FO. The block HB can he removed from and replaced in the hollow body GL in simple fashion. Naturally, a block of other firm material can be used in place of hard rubber.
In the exemplary embodiment illustrated in Figure 1, the light detector FO is arranged to face the gas flow. The light source LO is arranged at an angle to the light detector FO, e.g. at 60".
The function of the device illustrated in
Figure 1, is as follows: the light source LQ transmits light at an angle to the inner wall IW of the hollow body GL. On the inner wall IW of the hollow body GL, a small portion of the light is reflected and/or scatters, and some is incident on the perpendicularly arranged light detector FO. Since it has been assumed that no pollutant particles have yet been deposited on the probe SO, the signal emitted by the light detector is small. and is referred to as a dark signal. The major part of the transmitted light penetrates the light-permeable hollow body GL and is absorbed on the blackened pipeline surface in the vicinity of the probe SO.
If the gas flow containing particles, e.g.
toner particles which emanate from a cleansing device in a non-mechanical printer, now enters the pipeline LA, some become deposited on the outer wall AW of the hollow body GL on the portion facing the flow. The deposition of the particles on the outer wall
AW of the hollow body GL produces a reflective and/or scattering effect to increase the level of radiation transmitted from the light source LQ to the light detector FO, and so produces a change in the signal emitted from the light detector FO. The signal which is now emitted can be referred to as a bright signal.
The signal from the light detector FO is fed to a threshold value circuit which is connected to the light detector FO via selected ones of the conductors DL. One exemplary embodiment of a threshold value circuit of this kind is illustrated in Figure 2. It contains an operational amplifier OP, whose input is connected to the light detector FO, in this case a photo-transistor FT. The collectoremitter path of the photo-transistor FT is arranged between an input 1 of the operational amplifier OP and an operating potential V2, e.g. O.V. The input 1 of the operational amplifier OP is further connected via a limiting resistor R2 and a setting resistor
R3 to a further operating potential V1, e.g.
5V. The threshold of the threshold value circuit can be set with the aid of the variable resistor R3. The signal emitted from the photo-transistor FT is thus fed to the input 1 of the operational amplifier OP, and when this signal exceeds the threshold value of the operational amplifier OP, an output signal, serving as a fault indication signal, appears at the output 4 of the operational amplifier
OP, across a load resistor R4.
Figure 2 also illustrates the circuit of the light source LQ, which is a luminescent diode connected between the operating potential V1 to the operating potential V2 via a further resistor Ri. The current flowing through the luminescent diode is established with the aid of the resistors R1.
Arrows arranged between the light source LQ and the photo-transistor FT indicate that light is passing from the light source LQ onto the photo-transistor FT.
WHAT WE CLAIM IS:- 1. A fluid flow pollutant monitoring system comprising a pipeline through which a fluid is flowing, a probe arranged to project into said pipeline, and having a lightpermeable hollow body containing a light source positioned to illuminate that wall portion of the hollow body on which the said flow is incident, and also containing a light detector positioned within the hollow body to receive a component of any light reflected and/or scattered from this wall and so produce a signal proportional to the reflected and/or scattered light strength.
2. A system as claimed in Claim 1, in which the inner walls of said pipeline are blackened in the vicinity of the probe, and the probe is arranged in the pipeline at right angles to the direction of flow.
3. A system as claimed in Claim 1 or
Claim 2, in which at least at one end the hollow body projects from the pipeline to allow conductor connections to be made to the light source and the light detector.
4. A system as claimed in any preceding
Claim, in which the light source is arranged at an angle to said wall side of the hollow body and the light detector is arranged at right angles to said wall.
5. A system as claimed in any preceding
Claim, in which the light source and the light detector are arranged in a common block for insertion into the hollow body.
6. A system as claimed in any preceding
Claim, in which the light detector is connected to a threshold value circuit which emits an output signal when the signal from the light detector exceeds the threshold value.
7. A system as claimed in any preceding
Claim, in which the light source consists of a
GaAs luminescent diode.
8. A system as claimed in any preceding
Claim, in which the light detector consists of a photo-transistor.
9. A system as claimed in any preceding
Claim, in which the hollow body is a glass tube.
10. A system as claimed in Claim 6, or any one of Claims 7 to 9 when dependent upon Claim 6, in which said threshold value circuit consists of an operational amplifier whose input is connected via a variable resistor chain to a first operating potential supply terminal and via the collector-emitter path of the photo-transistor to a second operating potential supply terminal.
11. A fluid flow pollutant monitoring system substantially as described with reference to Figures 1 and 2.
12. A non-mechanical printer having a monitoring system as claimed in any preceding Claim to detect toner residues in the air emanating from a filter arrangement arranged in a cleansing device for the intermediate carrier of the printer.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (12)
- **WARNING** start of CLMS field may overlap end of DESC **.bright signal.The signal from the light detector FO is fed to a threshold value circuit which is connected to the light detector FO via selected ones of the conductors DL. One exemplary embodiment of a threshold value circuit of this kind is illustrated in Figure 2. It contains an operational amplifier OP, whose input is connected to the light detector FO, in this case a photo-transistor FT. The collectoremitter path of the photo-transistor FT is arranged between an input 1 of the operational amplifier OP and an operating potential V2, e.g. O.V. The input 1 of the operational amplifier OP is further connected via a limiting resistor R2 and a setting resistor R3 to a further operating potential V1, e.g.5V. The threshold of the threshold value circuit can be set with the aid of the variable resistor R3. The signal emitted from the photo-transistor FT is thus fed to the input 1 of the operational amplifier OP, and when this signal exceeds the threshold value of the operational amplifier OP, an output signal, serving as a fault indication signal, appears at the output 4 of the operational amplifier OP, across a load resistor R4.Figure 2 also illustrates the circuit of the light source LQ, which is a luminescent diode connected between the operating potential V1 to the operating potential V2 via a further resistor Ri. The current flowing through the luminescent diode is established with the aid of the resistors R1.Arrows arranged between the light source LQ and the photo-transistor FT indicate that light is passing from the light source LQ onto the photo-transistor FT.WHAT WE CLAIM IS:- 1. A fluid flow pollutant monitoring system comprising a pipeline through which a fluid is flowing, a probe arranged to project into said pipeline, and having a lightpermeable hollow body containing a light source positioned to illuminate that wall portion of the hollow body on which the said flow is incident, and also containing a light detector positioned within the hollow body to receive a component of any light reflected and/or scattered from this wall and so produce a signal proportional to the reflected and/or scattered light strength.
- 2. A system as claimed in Claim 1, in which the inner walls of said pipeline are blackened in the vicinity of the probe, and the probe is arranged in the pipeline at right angles to the direction of flow.
- 3. A system as claimed in Claim 1 or Claim 2, in which at least at one end the hollow body projects from the pipeline to allow conductor connections to be made to the light source and the light detector.
- 4. A system as claimed in any preceding Claim, in which the light source is arranged at an angle to said wall side of the hollow body and the light detector is arranged at right angles to said wall.
- 5. A system as claimed in any preceding Claim, in which the light source and the light detector are arranged in a common block for insertion into the hollow body.
- 6. A system as claimed in any preceding Claim, in which the light detector is connected to a threshold value circuit which emits an output signal when the signal from the light detector exceeds the threshold value.
- 7. A system as claimed in any preceding Claim, in which the light source consists of a GaAs luminescent diode.
- 8. A system as claimed in any preceding Claim, in which the light detector consists of a photo-transistor.
- 9. A system as claimed in any preceding Claim, in which the hollow body is a glass tube.
- 10. A system as claimed in Claim 6, or any one of Claims 7 to 9 when dependent upon Claim 6, in which said threshold value circuit consists of an operational amplifier whose input is connected via a variable resistor chain to a first operating potential supply terminal and via the collector-emitter path of the photo-transistor to a second operating potential supply terminal.
- 11. A fluid flow pollutant monitoring system substantially as described with reference to Figures 1 and 2.
- 12. A non-mechanical printer having a monitoring system as claimed in any preceding Claim to detect toner residues in the air emanating from a filter arrangement arranged in a cleansing device for the intermediate carrier of the printer.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19762654726 DE2654726C2 (en) | 1976-12-02 | 1976-12-02 | Device for monitoring a gas flow for particles present in it |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1589333A true GB1589333A (en) | 1981-05-13 |
Family
ID=5994534
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB5024277A Expired GB1589333A (en) | 1976-12-02 | 1977-12-02 | Fluid-flow pollutant monitoring systems |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5370481A (en) |
| AT (1) | AT351935B (en) |
| BE (1) | BE861450A (en) |
| CH (1) | CH621193A5 (en) |
| DE (1) | DE2654726C2 (en) |
| GB (1) | GB1589333A (en) |
| IT (1) | IT1088755B (en) |
| NL (1) | NL7713310A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9383317B2 (en) | 2011-08-22 | 2016-07-05 | Endress+Hauser Conducta Gmbh+Co. Kg | Optical sensor, especially for determining substance concentrations in aqueous solutions by means of a fluorescence measurement |
| CN109374474A (en) * | 2018-12-05 | 2019-02-22 | 海宁市英德赛电子有限公司 | Electronic grade high-purity ammonia micro impurity element fast testing system |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3030499C2 (en) * | 1980-08-12 | 1982-05-27 | Siemens AG, 1000 Berlin und 8000 München | Arrangement for the detection of particles in a gas flow |
| DE3722693C1 (en) * | 1987-07-09 | 1988-05-05 | Sonnenschein Accumulatoren | Monitoring device for the quality of a working filter |
| DE10133970B4 (en) * | 2001-07-17 | 2009-01-02 | Iav Gmbh Ingenieurgesellschaft Auto Und Verkehr | Apparatus for determining the density and concentration of visible constituents in fluids |
| DE102010026068B4 (en) | 2010-07-05 | 2017-09-28 | Emz-Hanauer Gmbh & Co. Kgaa | Optical sensor, in particular for installation in a washing machine or a dishwasher of household equipment |
| US8648321B2 (en) | 2010-07-05 | 2014-02-11 | Emz-Hanauer Gmbh & Co. Kgaa | Optical sensor for use in a domestic washing machine or dishwasher |
| DE102019122096A1 (en) | 2019-08-16 | 2021-02-18 | Endress+Hauser Conducta Gmbh+Co. Kg | Optochemical sensor and method |
-
1976
- 1976-12-02 DE DE19762654726 patent/DE2654726C2/en not_active Expired
-
1977
- 1977-07-22 AT AT536877A patent/AT351935B/en not_active IP Right Cessation
- 1977-11-14 CH CH1384877A patent/CH621193A5/en not_active IP Right Cessation
- 1977-12-01 IT IT3024877A patent/IT1088755B/en active
- 1977-12-01 NL NL7713310A patent/NL7713310A/en not_active Application Discontinuation
- 1977-12-02 GB GB5024277A patent/GB1589333A/en not_active Expired
- 1977-12-02 BE BE183129A patent/BE861450A/en unknown
- 1977-12-02 JP JP14561577A patent/JPS5370481A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9383317B2 (en) | 2011-08-22 | 2016-07-05 | Endress+Hauser Conducta Gmbh+Co. Kg | Optical sensor, especially for determining substance concentrations in aqueous solutions by means of a fluorescence measurement |
| CN109374474A (en) * | 2018-12-05 | 2019-02-22 | 海宁市英德赛电子有限公司 | Electronic grade high-purity ammonia micro impurity element fast testing system |
Also Published As
| Publication number | Publication date |
|---|---|
| ATA536877A (en) | 1979-01-15 |
| AT351935B (en) | 1979-08-27 |
| DE2654726C2 (en) | 1978-11-23 |
| CH621193A5 (en) | 1981-01-15 |
| JPS5370481A (en) | 1978-06-22 |
| DE2654726B1 (en) | 1978-03-16 |
| IT1088755B (en) | 1985-06-10 |
| BE861450A (en) | 1978-06-02 |
| NL7713310A (en) | 1978-06-06 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PCNP | Patent ceased through non-payment of renewal fee |