BACKGROUND OF THE INVENTION
Field of the Invention
[0001] This invention relates to a dry cleaning machine and a method of dry cleaning using
a solvent as a detergent and preventing contamination of the washing caused conversely
by washing.
Description of the Related Art
[0002] Fig. 5 is showing a constitutional block diagram of a dry cleaning machine of prior
art.
[0003] In Fig.5, a drum-formed washing tank 1 is for washing the washing by rotating drum,
throwing the washing into the drum tank, supplying a detergent (tetrachloroethylene
or the like). The contaminated detergent after using is stored in a lower tank 2.
This detergent is sent into a filtering tank 4 and forwarded to a refining tank 5
by a pressure pump 3. In the refining tank 5, the detergent is refined to remove odors,
acids and colors with filters, activated carbon and the like and then returned into
the drum tank 1 to be reused.
[0004] In the dry cleaning machine shown in Fig. 5, washing power of the detergent is remarkably
sunk by cyclical use, even though the contaminated detergent is refined in the refining
tank. Therefore, in a conventional dry cleaning machine, a detergent collecting unit
as shown in Fig. 6 is appended. In this detergent collection unit, the heavy contaminated
detergent in the washing tank 1 is sent into a distiller 6. The contaminated detergent
in the distiller 6 is heated to vaporize the detergent and other moisture and the
vaporized gas is forwarded to a condenser 7. The vaporized gas in the condenser 7
is liquefied by chiller water and is separated to detergent and water through a water
separator 8. The detergent is sent to a collection tank 9 and the separated water
is sent to a separated water tank 10. The detergent collected in the collection tank
9 is forwarded to the washing tank 1 to be used.
[0005] On the other hand, a dry cleaning machine has washing property as shown in Fig. 7.
The washing property in Fig. 7 shows phenomena of contaminator dissolving into the
detergent and the washing property curve (a) shows contamination is maximized in a
short time and is going down slowly after the peak. Thus, in the washing property,
the detergent contamination becomes the maximum roughly at one minute and 30 seconds
after starting, slightly depending on the washing type or contaminator type. In Fig.7,
the vertical axis indicates detergent contamination and the horizontal axis indicates
washing time.
[0006] The dry cleaning machine, shown in Fig. 5, uses cyclically refined detergent to send
the contaminated detergent through a filtering tank and a refining tank. Owing to
the detergent contamination becomes the maximum in a short time, shown in Fig.7, there
is apprehension to contaminate the washing conversely by washing. In addition, the
detergent filtering in the filtering tank works well just after the dry cleaning machine
running, but, as increasing washing cycle number, some waste threads, dirty oil or
other dirt in the detergent stick on a filter and clog up the filter. When clogging
up the filter, filtering efficiency is rapidly sinking and a volume of detergent flowing
is going down. As washing performance cannot be kept if the volume of detergent flowing
goes down, in general, increasing the detergent pressure in the filtering tank to
keep the volume of detergent flowing maintains the washing performance of the dry
cleaning machine. That, however, cannot solve the issue of contaminating the washing
conversely by washing. Furthermore, there is apprehension that increasing detergent
pressure in the filtering tank damages the filtering tank or the refining tank easily
and then it possibly contaminates the washing by supplying contaminated detergent
to the washing tank
[0007] Even if reusing detergent distilled by the distiller shown in Fig. 6, the detergent
contamination becomes the maximum in a short time after washing starting because of
no deference on washing property of the dry cleaning machine shown in Fig. 7. There
are still issues of contaminating the washing conversely by washing and bad hygiene.
[0008] US-A-5,943,720 discloses a dry cleaning machine and a process which eliminates solvent
emissions. With this dry cleaning machine, the solvent is separated based on the anticipated
extend of contamination wherein the less clean solvent is cleaned via a distillation
unit. This pre-known dry cleaning system comprises a cleaner/dryer unit, a heating
unit connected to said cleaner/dryer unit, two solvent tanks separately connected
to said cleaner/dryer unit, wherein a first solvent tank is used to maintain clean
solvent and a second tank is used to maintain less clean solvent and wherein a distillation
unit is connected to said second solvent tank such that the less clean solvent may
be periodically transported to and distilled in said distillation unit and thereafter
be returned to said first solvent tank free from contaminants and wherein said first
solvent tank and said second solvent tank are connected such that upon the solvent
level of said first solvent tank reaching a predetermined level, additional solvent
will flow to said second tank by gravity.
SUMMARY OF THE INVENTION
[0009] This invention has been accomplished to overcome the above drawbacks, and an object
of this invention is to avoid contaminating the washing conversely by contaminated
detergent by providing a dry cleaning machine and a method of dry cleaning, solving
hygienic issues.
[0010] According to the invention, this object is attained by a dry cleaning machine having
features of claim 1 and by a method of dry cleaning according to claim 4.
[0011] Further, advantageous embodiments of the dry cleaning machine are specified in dependent
claims 2 and 3, whereas a further embodiment of the method is characterised in claim
5.
[0012] In the dry cleaning machine according to the invention by detecting contamination
level of the detergent discharged from the washing tank with the contamination detector,
the detergent channel from the washing tank to the filtering tank is switched to the
contaminated detergent tank and the detergent is stored there, before the detergent
contamination becomes the maximum in a short time after starting washing. After that,
the contaminated detergent is sent to the distiller and vaporized in the distiller.
The vaporized gas is forwarded to the condenser and condensed by chiller water and
reused as refined detergent.
[0013] Advantageously with the dry cleaning machine mentioned above, a second detector is
mounted in a channel to supply detergent from the filtering tank to the washing tank
for detecting the detergent contamination level in the channel.
[0014] In this dry cleaning machine, the detergent contamination, after the filtering tank,
can be detected by the second detector mounted there. In the other word, when the
detergent contamination after the filtering tank increases, it makes definition of
some damages in the filter occurred, and supplying the detergent from the filtering
tank to the washing tank can be stopped, and then contaminating the washing conversely
by washing can be prevented.
[0015] Advantageously with the all dry cleaning machines mention above, the detector for
detergent contamination level is of an image processing means, such a CCD camera or
the like, to sense the detergent contamination level.
[0016] In all these dry cleaning machines, as the detector for detergent contamination is
a CCD camera, it cannot sense only the detergent contamination but also a lot of waste
threads mixed in the detergent. Therefore, it can prevent rapid clogging up the filtering
tank.
[0017] In order to attain the objects, there is also provided a method of dry cleaning comprising
the steps of supplying the washing and detergent to wash the washing in a washing
tank, detecting detergent contamination level just after washing while treating used
detergent in a filtering tank and reusing the detergent in the washing tank and shutting
the detergent supply to the filtering tank and supplying fresh detergent to the washing
tank to prevent the detergent contamination level is over prescribed threshold level
when the detergent contamination level reaches prescribed threshold level.
[0018] In this cleaning method, contaminating the washing conversely by washing can be prevented
as detecting the detergent contamination level discharged from the washing tank during
washing. Then, the detergent can be used by circulating and also reused by distiller.
[0019] Advantageously, with the cleaning method mentioned above, the contamination level
of detergent, supplied from the filtering tank to the washing tank, is detected and
a channel from the filtering tank to the washing tank is closed to shut the detergent
supply when the contamination level indicates an abnormal value.
[0020] In the cleaning method, contaminating the washing conversely by washing can be prevented
and also the filtering tank damage can be detected because contamination level of
the detergent transmitted from the filtering tank to the washing tank is detected.
As a matter of course, when detecting rapidly increased contamination of the detergent,
it is defined to occur some damages on the filter and then indicating or warning of
the filter damage can urge to replace filter of the filtering tank.
EFFECT of INVENTION
[0021] As mentioned above, according to this invention, the dry cleaning machine detects
detergent contamination discharged from a washing tank then if the contamination level
goes over prescribed value, stores the contaminated detergent in a contaminated detergent
tank temporarily and supplies fresh detergent to the washing tank to prevent contaminating
the washing conversely by washing. Therefore, the dry cleaning machine can use circulating
detergent and clean the washing to supply clean detergent always not contaminating
the washing to the washing tank.
[0022] According to this invention, the dry cleaning machine can prevent to contaminate
the washing conversely by washing as cutting off the line to supply detergent from
a filtering tank to a washing tank and supplying fresh detergent to the washing tank
when detecting the contamination of detergent supplied from the filtering tank to
the washing tank. Then, this is an excellent hygienic cleaning method.
[0023] According to this invention, the dry cleaning machine can detect reducing the light
transmittance caused by darkened detergent with contamination as taking images of
the detergent discharged from the washing tank by CCD camera. Moreover, advantageously
the dry cleaning machine can prevent immoderate clogging of the filtering tank as
judging abnormal condition by processing the image data even if a lot of waste thread
or down mix into the detergent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024]
Fig. 1 is a constitutional block diagram, showing one embodiment of a dry cleaning
machine according to this invention;
Fig. 2A, 2B are sectional views of examples of contamination detectors;
Fig. 3 is a graph and timing charts to explain the cleaning method which prevents
contaminating the washing conversely by washing to detect detergent contamination
in a dry cleaning machine according to this invention;
Fig. 4 is a graph and timing charts to explain the cleaning method which prevents
contaminating the washing conversely by washing to detect detergent contamination
supplied from the filtering tank in a dry cleaning machine according to this invention;
Fig. 5 is a block diagram to explain a dry cleaning machine by prior art;
Fig. 6 is a block diagram to explain a dry cleaning machine by prior art;
Fig. 7 is a graph to explain washing property of a dry cleaning machine;
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] Some embodiments of dry cleaning machines and cleaning methods according to this
invention will now be described with reference to the attached drawings.
[0026] Fig. 1 is showing a block diagram of one embodiment of a dry cleaning machine according
to this invention. In Fig.1, a washing tank 10 is a shower drum type for washing the
washing and preferably soaking type, shower type or jet type is effective and also
combination type of these types is effective. A detergent tank 11 stores detergent
and a rinse tank 12 stores rinse. Washing is done after inputting the washing and
detergent (tetrachloroethylene or the like) into the washing tank 10. The detergent
for initial use can be supplied directly through fresh detergent line L1 to the washing
tank 10 or can also be supplied through circulating line L3, L4.
[0027] The detergent, discharged from the washing tank 10, is sent by pressure to the filtering
tank 16 through a detergent discharging line L2, next a button trap 13 and next a
circulating line L3 having a circulation pump P1 in the line. The detergent after
the filtering tank 16 is supplied to the washing tank 10 through a circulating line
4. The detergent, discharged from the washing tank 10, is monitored on contamination
level by a contamination detector D1, mounted in the detergent discharging line L2.
The detergent, supplied from the filtering tank 16 to the washing tank 10, is monitored
by a contamination detector D2, mounted in the circulating line L4. By way of the
contamination detectors D1, D2, a CCD camera, a couple of light emitting elements
and light receiving elements or a module of reflective millers and a couple of light
emitting elements and light receiving elements or the like is used.
[0028] This dry cleaning machine includes of a distiller 14 for distilling contaminated
detergent to reuse the detergent, a condenser 15 for condensing gas vaporized in the
distiller 14 and a contaminated detergent tank 17 for storing the contaminated detergent
temporarily. The detergent to the distiller 14 is supplied through the button strap
13 or the contaminated detergent tank 17.
[0029] Switch valves V3, V6 are mounted in the circulating line L3, wherein a contaminated
detergent returning line L5 is branched off. The contaminated detergent returning
line L5, wherein switching valves V8, V9 are mounted, is connected to the contaminated
detergent tank 17. The contaminated detergent tank 17 is connected to the distiller
14 by the contaminated detergent returning line L6, wherein a switching valve V10
is mounted. Furthermore, the distiller 14 is connected to the condenser 15 by a vaporized
gas sending line L7. The condenser 15 is connected to the detergent tank 11 by a condensed
liquid sending line L8, for supplying condensed and liquefied detergent in the condenser
15 to the detergent tank 11.
[0030] A control unit 20 including CPU, provided in the dry cleaning machine, receives data
output from the contamination detectors D1, D2 and controls the switching valves V1
to V10 with processing the data from the contamination detectors D1, D2.
[0031] In the next, the contamination detectors D1, D2 will be described with reference
to Fig. 2A and 2B. As the contamination detectors D1 D2 have the same structure, only
the contamination detector D1 will be described herein. In Fig. 2A, the contamination
detector D1 is mounted in the detergent discharging line L2 or the circulating line
L4. A CCD camera 23 and a light emitting element 21, as the contamination detector
D1, are placed opposite to each other sandwiching a transparent pipe 22 in the middle.
The light emitting element 21, the transparent pipe 22 and the light receiving section
of the CCD camera 23 are covered with a shade material 24 to cut off external light
into the transparent pipe 22. Further, in Fig. 2B, the contamination detector D1 is
mounted in the detergent discharging line L2 or the circulating line L4. The light
emitting element 21 and a light receiving element 25, as the contamination detector
D1 are placed opposite to each other sandwiching a transparent pipe 22 in the middle.
The light emitting element 21, the transparent pipe 22 and the light receiving element
25 are covered with a shade material 24 to cut off external light into the transparent
pipe 22. The contamination detector D1 is mounted by connecting the detergent discharging
line L2 or the circulating line L4 on the both end of the contamination detector D1.
[0032] Preferably, the light emitting element 21 is placed at the same side of the CCD camera
23 or the light receiving element 25 to detect the detergent contamination by taking
a image of the reflective light or receiving the reflective light, instead of placing
the light emitting element 21 opposite to the CCD camera 23 or the light receiving
element 25.
[0033] In the next, working of the contamination detectors D1, D2 in Fig. 2A will be described
with reference to Fig. 1, 2A. The light, radiated from the light emitting element
21, irradiates the detergent flowing in the transparent pipe 22 through the transparent
pipe 22. The light, passing the detergent, is sensed by the CCD camera 23. The image
data from the CCD camera 23 is inputted to the control unit 20 and judged whether
over or under the prescribed threshold level on each pixel. The image data on each
pixel is defined as digital signal "1" for over the prescribed threshold level and
digital signal "0" for under the prescribed threshold level. And then, judgement whether
over the threshold level or not is done by total sum of all digital signals of each
pixel of the image and defines "1" for over the threshold level and "0" for under
the threshold level. When the judgement of total sum is "1", the detergent contamination
is defined to reaches the prescribed level. Thus, as the detergent contamination is
defined numerically and the contamination is detected by total sum of each pixel digital
signals, on the situation of detergent contamination mixed with a lot of waste thread
or down waste the detection can be done.
[0034] The contamination detectors D1, D2 in Fig. 2B will be described here. The contamination
detectors D1, D2 are mounted in the detergent discharging line L2 or the circulating
line L4. The light from the light emitting element 21 is received by the light receiving
element 25 through the transparent pipe 22. The output of the light receiving element
25 depends on light transmittance changing caused by the detergent contamination level
and indicates the smaller transmitted light power the more detergent contamination.
Then, the control unit 20 judges "1" by output from the contamination detectors D1,
D2 when the output of the light receiving element 25 reaches the prescribed level.
[0035] If the contamination detectors D1, D2 in Fig. 2B are mounted in the circulation line
L4, it can detect to supply the contaminated detergent to the washing tank 10 or can
judge to occur the filter damage in the filtering tank 16. Setting low detecting level
(threshold level) for detergent contamination, damage of the filtering tank can be
detected earlier and contaminating the washing conversely by washing can be solved.
Preferably, inputting the output of the contamination detector D2 into the control
unit 20 and monitoring time-dependent change of detergent contamination change, the
filter damage of the filtering tank 16 can be detected by rapid change of the detergent
contamination.
[0036] In the next, a dry cleaning method to prevent contaminating the washing conversely
by washing in a dry cleaning machine according to this invention will be described
with reference to Fig. 1, 3 and 4. In Fig. 3-A shows washing property curves (a),
(b) and Fig. 3-B shows working condition of the circulating pump P1 and Fig. 3-C,
D, E and F show each working condition of switching valves V3, V6 and V7, V8 and V9,
V2 and V2.
[0037] On this embodiment of dry cleaning machines, the switching valves V3, V6, V7 are
opened and the switching valves V8, V9 are closed in starting operation. As the switching
valves V4, V5 are opened in certain level, the detergent and rinse are mixed to be
usable. The mixed detergent is supplied from the filtering tank 16 to the washing
tank 10 through the circulating line L3 by operating the circulating pump P1. By rotating
the drum of the washing tank 10, washing the washing is started. The contamination
level of the detergent, discharged from the washing tank 10, is detected by the contamination
detector D1. The output of the contamination detector D1 is inputted into the control
unit 20. As shown in Fig. 3-A, the property shows the detergent contamination becomes
the maximum in a short time (time T2) after starting washing. Therefore, eliminating
the maximum peak, when the output of the contamination detector D1 goes over the prescribed
threshold level (time T1), the switching valves V6, V7 are closed as shown in Fig.
3D to cut off the circulating line L3 from the washing tank 10 to the filtering tank
16 and the circulating line L4 from the filtering tank 16 to the washing tank 10.
In the other hand, the switching valves V8, V9 in the detergent returning line L5
are opened as shown in Fig. 3-E.
[0038] In the next, when the switching valves V6, V7 are closed and the switching valves
V8, V9 in the contaminated detergent return line L5 are opened, the contaminated detergent
is supplied to the contaminated detergent tank 17 through the contaminated detergent
return line L5. In the meantime, the switching valves V1, V2 is opened and detergent,
mixed by the detergent and rinse from the detergent tank 11 and the rinse tank 12,
is supplied directly to the washing tank and the washing is washed. After passing
the prescribed time (the time between T1 and T2 in Fig. 3-A is required time that
detergent contamination is changing from the prescribed threshold level to the maximum),
the switching valves V6, V7 are opened and the switching vales V8, V9 and V1, V2 are
closed. Then the initial condition is set again. The contaminated detergent, sent
to the contaminated detergent tank 17, is forwarded at suitable intervals to the distiller
14 through the contaminated detergent return line L6. The contaminated detergent is
heated and vaporized in the distiller 14 and the vaporized gas of the contaminated
detergent is forwarded to the condenser 15 to be condensed and liquefied by chiller
water. The liquefied detergent is sent to the detergent tank 11 through the condensed
detergent transport line L8.
[0039] Thus, the control unit 20 can improve the washing property like Washing property
curve as shown in Fig. 3-B, for supplying fresh detergent directly to the washing
tank by controlling each switching vales, sending control signals to each switching
valve before the detergent contamination becomes the maximum. Then, contaminating
the washing conversely by washing can be solved and cyclically use of the detergent
can be worked.
[0040] In the next, prevention to contaminate the washing conversely caused by filer damage
of the filtering tank in a dry cleaning machine will be described with reference to
Fig. 4. The curve (b) in Fig. 4-A shows the washing property curve by the operation
method to prevent above conversely contamination. The curve (c) in Fig. 4-A shows
contaminated detergent leaking when the filter of the filtering tank is damaged. Solving
to contaminate the washing conversely by such filter damage, the contamination detector
D2 is mounted in the circulating line L4 from the filtering tank 16 to the washing
tank 10.
[0041] The contamination detector D2 is detecting the contamination level of detergent flowing
in the circulating line L4. When the output of the contamination detector D2 is over
the prescribed threshold level (in the condition as shown in Fig. 4-A, C), the switching
valve V7 is closed and the switching valve V9 is opened as shown in Fig. 4-D, F. Then,
the detergent passed through the filtering tank 16 is sent to the contaminated detergent
tank 17. In the meantime, the switching valves V1, V2 are opened as shown in Fig.
4-G and fresh detergent is supplied to the washing tank 10 through fresh detergent
line L1 and this condition is kept until washing finished. The switching valves V6,
V8 are kept as shown in Fig. 4-C, E. The contamination level of the detergent, discharged
from the washing tank 10, is detected by the contamination detector D1 as shown in
Fig. 3-A. When the detergent contamination level is over the prescribed threshold
level, the switching valves V6, V7 is closed to cut off the circulating line L4 from
the washing tank 10 to the filtering tank 16 and the switching valves V8, V9, mounted
in the contaminated detergent return line L5, are opened to send the contaminated
detergent to the contaminated detergent tank 17.
[0042] On the other hand, the switching valve V10, mounted in the contaminated detergent
return line L6, is opened and the contaminated detergent in the contaminated detergent
tank 17 is forwarded to the distiller 14. The vaporized gas by heating and vaporizing
the contaminated detergent in the distiller 14 is sent through the vaporized gas transport
line L7 to the condenser 15 to be condensed and liquefied by chiller water. The liquefied
detergent is returned to the detergent tank 11 through the condensed detergent transport
line L8.
[0043] Detecting the contamination of the detergent from the filtering tank 16 and controlling
as mentioned above can give the washing property as shown in Fig. 4-D. In addition,
as the filter in the filtering tank 16 can be exchanged after washing the washing
finished, the maintenance of the filtering tank is made easy. Preferably, in case
of detecting abnormal condition by the contamination detector D2, indicating or alarming
filter damage, then stopping operation temporarily, then exchanging filter in the
filtering tank 16, then restarting operation is effective.
[0044] Preferably, instead of detecting the detergent contamination by inputting image data
by a CCD camera continuously to the control unit, detecting both of image data by
a CCD camera and output signal by a light receiving element and inputting the data
and the signal to the control unit to sense the detergent contamination is also effective.
[0045] Advantageously, a dry cleaning machine having only one contamination detector D1
can solve issue to contaminate the washing conversely by washing. Mounting the second
contamination detector D2 in the dry cleaning machine can prevent more effectively
contaminating the washing conversely by washing.
1. Trockenreinigungsmaschine mit:
einem Waschbehälter (10) zum Waschen der Wäsche mittels eines Reinigungsmittels, welches
aus einem Reinigungsmittelbehälter (11) zugeführt wird;
einem Filtrierbehälter (16) zum Raffinieren eines aus dem Waschbehälter (10) ausgeschiedenen,
verunreinigten Reinigungsmittels und Zuführen des raffinierten Reinigungsmittels zum
Waschbehälter (10);
einem Verunreinigungsdetektor (D1) zum Erfassen des Verunreinigungspegels des Reinigungsmittels
nach der Verwendung im Waschbehälter (10);
einem Behälter (17) für verunreinigtes Reinigungsmittel zum vorübergehenden Speichern
des verunreinigten Reinigungsmittels während dem Schließen des das Reinigungsmittel
zuführenden Kanals vom Waschbehälter (10) zum Filtrierbehälter (16), wenn der Verunreinigungspegel
über dem vorgeschriebenen Schwellenpegel ist;
einer Destilliervorrichtung (14) zum Destillieren des verunreinigten Reinigungsmittels
aus dem Behälter (17) des verunreinigten Reinigungsmittels; und
einem Kondensator (15) zum Kondensieren des verdampften, verunreinigten Reinigungsmittels
in der Destilliervorrichtung (14) und Leiten des kondensierten Reinigungsmittels zum
Reinigungsmittelbehälter (11).
2. Trockenreinigungsmaschine nach Anspruch 1, wobei ein zweiter Detektor (D2) in einem
Kanal (24) zum Zuführen des Reinigungsmittels vom Filtrierbehälter (16) zum Waschbehälter
(10) zum Erfassen des Verunreinigungspegels des Reinigungsmittels im Kanal (24) befestigt
ist.
3. Trockenreinigungsmaschine nach Anspruch 1 oder 2, wobei der Verunreinigungsdetektor
(D1) zum Erfassen des Verunreinigungspegels des Reinigungsmittels eine Bildverarbeitungsvorrichtung
ist, wie z.B. eine CCD-Kamera oder ähnliches.
4. Trockenreinigungsverfahren, welches die folgenden Schritte aufweist:
Zuführen der Wäsche und des Reinigungsmittels zum Waschen des Wäsche im Waschbehälter
(10);
Erfassen des Verunreinigungspegels des Reinigungsmittels genau nach dem Waschen, während
das verwendete Reinigungsmittel in einem Filtrierbehälter (16) behandelt und das Reinigungsmittel
im Waschbehälter (10) wiederverwendet wird; und
Schließen der Reinigungsmittelzufuhr zum Filtrierbehälter (16) und Zuführen eines
frischen Reinigungsmittels in den Waschbehälter (10), um zu verhindern, dass der Verunreinigungspegel
des Reinigungsmittels über dem vorgeschriebenen Schwellenpegel ist, wenn der Verunreinigungspegel
des Reinigungsmittels den vorgeschriebenen Schwellenpegel erreicht.
5. Trockenreinigungsverfahren nach Anspruch 4, wobei der Verunreinigungspegel des vom
Filtrierbehälter (16) zum Waschbehälter (10) zugeführten Reinigungsmittels erfasst
wird und ein Kanal (24) vom Filtrierbehälter (16) zum Waschbehälter (10) geschlossen
wird, um die Reinigungsmittelzuführung zu schließen, wenn der Verunreinigungspegel
einen abweichenden Wert angibt.