DE10309518A1 - Assembly for trapping and classifying airborne particulate impurities, comprises a camera linked via a microcomputer to screen the presentation of germs, spores, bacteria and parasites - Google Patents

Abstract

An assembly that traps and classifies airborne particles comprises an ambient air supply to a trap substrate with a camera, where the substrate (2) is either a flat panel electrode, or is located at an electrode, located in proximity to but not in contact with a second electrode (1) unit, and the two electrodes (1, 2) are coupled to a high voltage current (4). The camera (6) is directed at the substrate (4) and the resulting image is presented on a screen (8) together with a count and classification of the trapped particle impurities. The second electrode is a spiral wire or a tubular emission electrode with or without tips (3). The second unit (1) consists of two or more electrodes, one of which bears a positive charge and the other a negative charge. The first electrode bears a reference potential. In conjunction with the camera the data processing system classifies the type, size, origin and number of trapped particles e.g. whether these be of biological non-biological origin.

Description

The invention relates to devices for the collection and determination of airborne particles with each at least one carrier for airborne Particles, an image recording device for particles on the carrier and a device for sucking in air.

The collection of airborne particles and their evaluation is known to be carried out by, among others the separation of the particles on a nutrient medium that is in a Shell is located. The basis is a suction effect that develops towards the nutrient medium. About the If the germs react as particles with the nutrient medium, the germs can be detected. A disadvantage is that only the live number can be determined is.

Filters for collecting the particles are used in further devices. Such a solution, among others, by DE 198 26 835 A1 (Arrangement and method for the automatic determination of airborne microorganisms, biotic and / or abiotic particles) known. The particles are separated on a filter membrane. This filter membrane has openings for the passage of air, which also represent bumps. The particles are not deposited on a smooth surface, so that the particles can only be separated using image evaluation methods with increased effort.

Another known device rests on a slide in the airflow that is adhesive is coated, whereby living and dead germs can be detected. The Disadvantage is the adhesive Layer that must be hidden during image evaluation. It have to constant layer thicknesses can be guaranteed in order to get from it to avoid resulting incorrect image evaluation. Furthermore are such slides through the adhesive layer via mechanisms only difficult to handle.

The specified in claim 1 The invention has for its object an easy to use Device for collecting airborne particles on one carrier and for the determination of airborne particles on the carrier create that airborne particles in short intervals are determinable.

This object is achieved with the in the claim 1 listed Features resolved.

The facilities for collection and Determination of airborne particles with at least one each carrier for airborne Particles, an image recording device for particles on the carrier and a device for drawing in air are particularly noteworthy characterized by the fact that airborne particles are quasi continuous or in discrete time intervals without large time intervals between collection and determination can be determined. Airborne particles to be determined are especially fungi, bacteria, Spores of fungi and bacteria, mycotoxins from mold, Parasites and cell components. Preferably a health hazard airborne particles and / or airborne particles as impurities are with the facilities according to the invention determined in the supply air.

In that the carrier either a flat Is or is located on a surface electrode and at a distance from the wearer at least one electrode is arranged between the carrier and the electrode when connecting to a high voltage source electric field. At the same time, ions are emitted from the electrode, that charge the airborne particles. Be over the electric field these charged airborne particles are transported to and on the carrier collected. This allows the carrier to be parallel for air flow, at a distance parallel to the air flow or at an angle from the Airflow away to be ordered. There are therefore no special adhesive layers on the carrier necessary. The carrier can be arranged so that the particles remain on the carrier. This also has the advantage that the carrier is not as a baffle for Particle is formed. Such a baffle plate must be angular arranged in the air flow to collect particles on it. At the same time as is known, these particles are kept on the surface through adhesive Layers can be done.

The determination of existing on the carrier Particle takes place with the image recording device, which with a Particles on the carrier identifying, counting, according to at least one characteristic, both determining and classifying image evaluation device is connected. A carrier as area Separation electrode or in connection with a surface electrode can advantageously be designed so that for image evaluation disturbing Structures are avoided. Such disturbing structures are particularly the adhesive Layers on the carrier, fluctuations in the layer thickness influence the image evaluation, or geometric unevenness of the surface, for example one To ensure air passage (Filter). The surface of the carrier more airborne Particles can thus be designed in such a way that due to surface unevenness or layers of incorrect determinations avoided as far as possible can be. At the same time, the surface in color and / or shape of the image recording device used and / or image evaluation device can be adapted so that safe and clear determinations of airborne particles are possible and incorrect determinations are largely avoidable.

Advantageous embodiments of the Invention are specified in claims 2 to 17.

Wire or tubular spray electro those with or without tips according to the further development of claim 2 are easily placed in the air flow. Spray electrodes are electrodes on which discharges occur in the air flow. Ions are emitted, which accumulate on particles in the air flow and thus ensure that these particles are charged.

Another advantage of this type of discharge electrodes is that they are easily adapted to the flow pattern can. Tips on the surface increase the field strength at these points, so lower tensions compared to none Pointed spray electrodes lead to discharges and thus the formation of ions.

At least two electrodes with a positive and a negative voltage potential are, after the further development of claim 3 form a positive and a negative corona in the airflow. The electrodes are advantageous arranged in such a way that the positive Corona is located in front of the negative corona. Through the positive corona connections are removed from the air flow, which otherwise are Corona suppression and thus a reduction in the current density of the negative corona can effect.

An arrangement of several carriers on one plate-shaped or star-shaped Carrier element, the is coupled with a rotary drive, according to the training of claim 4 leads advantageously to a device according to the invention, with the quasi-continuously and thus in discrete time intervals Particles of the air can be determined. It is located in each case at least one carrier in the stations collection of particles and image recording of the particles on the carrier. The carrier is removed after the image is captured. Continuing this arrangement with The development of claim 5, the particles the porters Removed the carrier after taking the picture in a station cleaning. This provides the user with a closed cycle. In Connection with the development of claim 6 form the Image recording device, the image evaluation device, the high voltage source and the rotary drive a control loop. Are controlled variables the number of particles and / or the presence of at least one by at least one characteristic of certain particle for the duration the connection between either the deposition electrode or the surface electrode and the high voltage source and for the rotary drive. The number of particles can be chosen such that, for example overlapping Particles during of deposition on the carrier can be largely avoided.

The user thus has a compact device according to the invention available through the automatically airborne particles in the air flow of a supply air line are determinable.

An arrangement of the wire-shaped or tubular spray electrode in the air duct after the further development of claim 7 can slightly over Spacer between the wall of the air duct and the spray electrode realize. The columnar spacers, for example are advantageously insulators. This is also a protection against accidental contact guaranteed so that further protective measures across from contact are not necessary.

The deposition electrode or the surface electrode are advantageously connected to earth as a reference potential.

An ultrasound transducer coupled to the carrier after the further development of claim 8 advantageously serves on the one hand cleaning the carrier on the particles on it and on the other hand the distribution the particle on the carrier before taking the picture.

The source of electromagnetic radiation after the development of claim 9 serves an improved Image of those on the carrier Particle. First, the area of the carrier while Illuminated for image acquisition or, on the other hand, particles can be on the support Emission of electromagnetic radiation. In the latter This can be done by adding at least one marker liquid the fluorescence or phosphorescence even after switching off the source cause particles with such properties over the Image acquisition can be determined.

A cheap image acquisition device is an electronic after the further development of claim 10 Image acquisition system with digital memory and interface for an electronic one Data processing device. This makes digital image data to disposal provided that is processed according to a wide variety of criteria can be.

Located between the particle and the lens of the image recording device after the training of claim 11 an immersion liquid, so the resolution limit improved. This is particularly due to the small object sizes of particles of particular importance, so that even smaller particles over the Image recording device can be recorded.

An advantageous image evaluation device consists of a further development of claim 12 Device for image segmentation, a device for separation overlapping particles, of a particle counting Facility, a facility for determining features and a Particle classifying facility.

Cheap Parameters for are a classification in the further development of the claim 13 listed.

Favorable facilities for the identification of the particles are after the training of the godfather Claim 14 either a device that works according to the threshold value method and evaluates the gray value distribution in a histogram of converted particles, or a device for image segmentation in the image evaluation device that works according to the watershed transformation.

The threshold method for image analysis is realizable with little effort and in real time. In the Consideration of the individual objects are both either expected value or mean as well as variance, but also the description of a Probability distribution with binomial or normal distribution used. about a histogram separates the individual objects so that their Contour and structure can be recorded and evaluated.

In the watershed transformation object contours are determined, with both lines and edges be extracted. A major advantage is that closed contours are generated. This follows from the definition since each catchment basin is separated from all neighboring ones by a Watershed must be separated.

At least one baffle in the airflow in front of the carrier after the further development of claim 15 leads to a turbulence of Air flow in the direction of flow behind the baffle. A cheap one Placement can advantageously result in a lower flow rate over the carrier the air is present, so that there are no particles on it be torn away.

He can air duct after training of claim 16 at least in front of the carrier either straight be or at least a curve have. In the latter case, you can Eddies arise or eddies are broken down.

The image evaluation device is after the development of claim 17 advantageously Part of the data processing device with a memory and at least one interface is interconnected. advantageously, at least the data processing device sends if present of a predetermined particle certain data on at least one Alarm device, so that this presence is perceptible.

Embodiments of the invention are shown in the drawings and are described in more detail below.

They each show as principal Presentation:

1 an arrangement of a carrier as a flat separating electrode and an electrode for collecting airborne particles,

2 an arrangement of a carrier on a surface electrode and an electrode for collecting airborne particles,

3 a facility for the collection and determination of airborne particles,

4 an arrangement of a carrier and an electrode for collecting airborne particles with an air channel and a device for sucking in air and

5 a facility for the collection and determination of airborne particles with multiple carriers.

1st embodiment

A device for collecting and determining airborne particles essentially consists of a device in a first exemplary embodiment 10 for sucking in air, an electrode 1, a carrier 2 for airborne particles, an image recording device 6 for particles on the carrier 2 and an image evaluation device 8th ,

The carrier 2 itself is either a flat deposition electrode or is located on a surface electrode 5 , At a distance from the wearer 2 is the wire-shaped and with tips 3 provided electrode 1 arranged as a spray electrode. The flat deposition electrode or the surface electrode are grounded as the reference potential and the electrode 1 with the negative pole of a high voltage source 4 connected together. The 1 and 2 show such arrangements as basic representations. Between the carrier 2 and the electrode 1 an electric field is formed.

The image capture device 6 is towards the wearer 1 with particles arranged so that particles can be captured. Such image recording devices 6 are particularly well-known digital cameras. The resolution limit can be improved by large aperture and immersion. The image capture device 6 is with the captured particle on the carrier 2 identifying, counting, according to at least one feature, both determining and classifying image evaluation device 8th connected. The image evaluation device 8th consists of an absorbed particle of the carrier 2 Extracting and individual particle-identifying device for image segmentation as the first component. This is either a device that works according to the threshold value method and evaluates the gray value distribution in a histogram of particles, or a device for image segmentation that works according to the watershed transformation.

With the threshold value method the particles taken up according to their gray value distribution converted into a histogram. This makes it possible to segment within the image to determine the individual particles.

In the watershed transformation, the numerical (gray) value of a pixel is interpreted as an elevation. This leads to a gray scale mountain range. The "drops" falling on the relief strive towards the regional minima along the strongest drop and form small dusts at these points CKEN. The watershed as a dividing line between two reservoirs results from the definition of all the points from which a "drop" strives for this minimum. The dividing line between two reservoirs has the property that a "drop" falling on one point of the dividing line into each of the two neighboring reservoirs can flow away equally. Both lines and edges can thus be detected (the mathematically strongest drop is equal to the gradient amount). The smaller and lower pools merge with each other by successive flooding so that all lines and contours are captured.

A second component of the image evaluation device is an absorbed and overlapping Particle both isolating and separating device, where these particles are separated using model-based methods.

A third component is one Particle counting Facility.

These particles are determined through the characteristics such as shape, texture, color, fluorescence, phosphorescence, Size, structure and possibly other features of interest in the facility for Characteristic determination described as fourth component.

• – Anzahl der Partikel unabhängig von ihrer Zusammensetzung und Herkunft,
• – Größe von Partikeln,
• – Textur von Partikeln,
• – Form von Partikeln,
• – Anzahl alveolengängiger Partikel,
• – Anzahl von Partikeln Biogenen Ursprungs,
• – Größe von Partikeln Biogenen Ursprungs,
• – Form von Partikeln Biogenen Ursprungs,
• – Anzahl toter Partikel Biogenen Ursprungs,
• – Anzahl lebensfähiger und eventuell vermehrungsfähiger Partikel Biogenen Ursprungs,
• – Arten oder Gattungen aufgrund charakteristischer Sporen- oder Pollenformen,
• - Verhältnis von luftgetragenen abiotischen zu biotischen Partikeln und
• – Verhältnis von toten zu lebensfähigen luftgetragenen Partikeln als Mikroorganismen der Klassifikation dient.

A fifth component is a particle classifying device, wherein at least one of the following parameters

• - number of particles regardless of their composition and origin,
• - size of particles,
• - texture of particles,
• - shape of particles,
• Number of respirable particles,
• - number of particles of biogenic origin,
• - size of particles of biogenic origin,
• - shape of particles of biogenic origin,
• - number of dead particles of biogenic origin,
• - number of viable and possibly reproductive particles of biogenic origin,
• - species or genera based on characteristic spore or pollen shapes,
• - ratio of airborne abiotic to biotic particles and
• - The ratio of dead to viable airborne particles serves as classification microorganisms.

The image evaluation device 8th is advantageously a component of a data processing device 7 for example in the form of a microcomputer or a computer that has at least one memory and at least one interface 9 features. The 3 shows a device for collecting and determining airborne particles in a basic representation. The control of the high voltage source 4 , the image recording device 6 and a movement mechanism 12 for the wearer 2 is advantageously carried out via the data processing device 7 , For this purpose, these components are with the data processing device 7 connected together.

In one embodiment, the data processing device 7 in the presence of at least one predetermined particle, certain data are sent to at least one alarm device.

2nd embodiment

In a second exemplary embodiment, a device for collecting and determining airborne particles essentially consists of one device 10 for sucking in air, an air duct 11 , an electrode 1, a carrier element with a plurality of carriers 2 for airborne particles, an image recording device 6 for particles on the carrier 2 and an image evaluation device 8th (Representations in the 4 and 5 , wherein the carrier element is not shown).

The carrier element is plate-shaped or star-shaped, rotatably mounted and coupled to a rotary drive. There is a first carrier 2 either in the air duct 11 with the electrode 1 or is part of the wall area of the air duct 11 with the electrode 1 , This is as wire-shaped and with tips 3 provided electrode 1 designed as a spray electrode. The electrode is via columnar spacers made of an electrical insulator 1 in the air duct 11 attached. The flat deposition electrode or the surface electrode are grounded as a reference potential and the electrode with the negative pole of a high voltage source 4 connected together. Between the carrier 2 and the electrode 1 an electric field is formed.

A second carrier 2 and the image pickup device 6 are arranged so that at least one image of particles on the carrier 2 via the image recording device 6 is recordable. The carrier 2 itself is either a flat deposition electrode or is located on a surface electrode.

The image capture device 6 , the image evaluation device 8th , the high voltage source 4 and the rotary drive are preferably components of a control circuit, the number of particles and / or at least one particle determined by at least one characteristic being a first control variable for the duration of the connection between either the separating electrode or the surface electrode and the high-voltage source 4 and are a second controlled variable for the rotary drive.

The image capture device 6 is towards the wearer 2 with particles arranged so that particles can be captured. Such image recording devices 6 are particularly well-known digital cameras. The resolution limit can be improved by large aperture and immersion. The image capture device 6 is up with the taken particles on the carrier 2 identifying, counting, according to at least one feature, both determining and classifying image evaluation device 8th connected. The realization of the image evaluation device 8th corresponds to that of the first embodiment.

In one embodiment of this embodiment is located after the image recording device 6 a cleaning device for a carrier 2 ,

For cleaning the carrier 2 it is coupled with an ultrasonic transducer. In one embodiment, the carrier 2 also be equipped with an ultrasonic transducer. The ultrasonic transducer is preferably a plate-shaped oscillator in the form of a piezoelectric ultrasonic transducer.

In a further embodiment of the exemplary embodiments there are at least one source for electromagnetic rays and the image recording device 6 so arranged that electromagnetic radiation of at least one wavelength onto the carrier 2 arrive and at least one image of particles on the carrier 2 via the image recording device 6 is recorded.

In a further embodiment, the distance to the carrier 2 at least two electrodes can be arranged. The deposition electrode or the surface electrode and the electrodes are connected together with high voltage sources such that one of the electrodes with the positive voltage potential, the other electrode with the negative voltage potential and the deposition electrode or the surface electrode with earth as the reference potential.

Claims (17)

Device for collecting and determining airborne particles, each with at least one carrier for airborne particles, an image recording device for particles on the carrier and a device for drawing in air, characterized in that the carrier ( 2 ) is either a flat deposition electrode or is located on a surface electrode that is at a distance from the carrier ( 2 ) at least one electrode ( 1 ) that the flat deposition electrode or the flat electrode and the electrode ( 1 ) with a high voltage source ( 4 ) are interconnected or interconnectable and that the image recording device ( 6 ) with a captured particle on the carrier ( 2 ) identifying, counting, according to at least one characteristic, both determining and classifying image evaluation device ( 8th ) connected is. Device according to claim 1, characterized in that the electrode ( 1 ) at least one wire or tubular spray electrode either with or without tips ( 3 ) is. Device according to claim 1, characterized in that at a distance from the carrier ( 2 ) at least two electrodes are arranged such that either the deposition electrode or the surface electrode and the electrodes are connected or can be connected to high-voltage sources such that one of the electrodes with the positive voltage potential, the other electrode with the negative voltage potential and the separation electrode or the surface electrode with the reference potential are connected. Device according to claim 1, characterized in that several carriers ( 2 ) are on a plate-shaped or star-shaped and rotatable support element and that the support element is coupled to a rotary drive in such a way that a support ( 2 ) either in an air duct ( 11 ) with the electrode 1 or part of an air duct ( 11 ) with the electrode ( 1 ) and that a carrier ( 2 ) and the image recording device ( 6 ) are arranged so that at least one image of particles on the carrier ( 2 ) via the image recording device ( 6 ) is recordable. Device according to claim 4, characterized in that several carriers ( 2 ) are on a plate-shaped or star-shaped and rotatable support element and that the support element is coupled to a rotary drive in such a way that a support ( 2 ) either in an air duct ( 11 ) with the electrode ( 1 ) or part of an air duct ( 11 ) with the electrode ( 1 ) is that a carrier ( 2 ) and the image recording device ( 6 ) are arranged so that at least one image of particles on the carrier ( 2 ) via the image recording device ( 6 ) is recordable, and that a carrier ( 2 ) can be coupled with a cleaning device. Device according to the claims 1 . 4 and 5 , characterized in that the image recording device ( 6 ), the image evaluation device ( 8th ), the high voltage source ( 4 ) and the rotary drive are components of a control circuit, the number of particles and / or at least one particle determined by at least one characteristic being a first control variable for the duration of the connection between either the separating electrode or the surface electrode and the high-voltage source ( 4 ) and a second control variable for the rotary drive. Device according to the claims 2 and 6 , characterized in that the wire-shaped or tubular spray electrode either with or without tips ( 3 ) at a distance from the carrier ( 2 ) in the air duct ( 11 ) is arranged. Device according to claim 1, characterized in that the carrier ( 2 ) is coupled to an ultrasonic transducer. Device according to claim 1, characterized in that a carrier ( 2 ), at least one source for electromagnetic radiation and the image recording device ( 6 ) are arranged so that electromagnetic radiation of at least one wavelength onto the carrier ( 2 ) and at least one image of particles on the carrier ( 2 ) via the image recording device ( 6 ) is recorded. Device according to claim 1, characterized in that the image recording device ( 6 ) an electronic image recording system with digital memory and interface for an electronic data processing device ( 7 ) is. Device according to the claims 1 and 10 , characterized in that the carrier ( 2 ) is provided with the particles for image recording with an immersion liquid and that the image recording device () 6 ) and the immersion liquid are in contact with each other. Device according to claim 1, characterized in that the image evaluation device ( 8th ) from a captured particle on the carrier ( 2 ) extracting and individual particle-identifying device for image segmentation, a recorded and superimposed particle, both isolating and separating device, a particle counting device, at least one of the features with regard to the shape, texture, color, fluorescence, phosphorescence, size and structure of particles determining device for determining features and a particle classifying device and that these devices in the image evaluation device ( 8th ) are connected. Device according to claim 1, characterized in that the at least one of the following parameters as - Number of the particles independently of their composition and origin, - size of particles, - texture of particles, - Shape of particles, - Number respirable Particle, - Number of particles of biogenic origin, - size of particles of biogenic origin, - form of Particles of biogenic origin, - Number of dead biogenic particles origin, - Number viable and possibly more reproductive Particles of biogenic origin, - Species or genera based on characteristic spore or pollen shapes, - Ratio of airborne abiotic to biotic particles and - Ratio of dead to viable Airborne particles classifying as microorganisms is. Device according to claim 1, characterized in that a particle-identifying component of the image evaluation device ( 8th ) is either a device for image segmentation which works according to the threshold value method and evaluates the gray value distribution in a histogram of converted particles, or a device for image segmentation which works according to the watershed transformation. Device according to claim 1, characterized in that in front of the carrier ( 2 ) at least one baffle plate is arranged in the air flow. Device according to the claims 1 and 6 , characterized in that the air duct ( 11 ) at least in front of the wearer ( 1 ) is either straight or at least has a curvature. Device according to the claims 1 and 10 , characterized in that the image evaluation device ( 8th ) part of the data processing facility ( 7 ) is that the data processing device ( 7 ) with a memory and an interface ( 9 ) is interconnected and that the data processing device which sends certain data in the presence of at least one predetermined particle to at least one alarm device ( 7 ) is.