CA2186275A1 - Method and apparatus for taking gas samples from containers - Google Patents
Method and apparatus for taking gas samples from containersInfo
- Publication number
- CA2186275A1 CA2186275A1 CA002186275A CA2186275A CA2186275A1 CA 2186275 A1 CA2186275 A1 CA 2186275A1 CA 002186275 A CA002186275 A CA 002186275A CA 2186275 A CA2186275 A CA 2186275A CA 2186275 A1 CA2186275 A1 CA 2186275A1
- Authority
- CA
- Canada
- Prior art keywords
- collecting chamber
- gas
- container
- opening
- medium
- 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.)
- Abandoned
Links
- 238000000034 method Methods 0.000 title claims abstract description 22
- 238000002347 injection Methods 0.000 claims description 16
- 239000007924 injection Substances 0.000 claims description 16
- 238000010926 purge Methods 0.000 claims description 12
- 238000005070 sampling Methods 0.000 claims description 7
- 238000004458 analytical method Methods 0.000 abstract description 10
- 238000000605 extraction Methods 0.000 abstract description 7
- 238000010790 dilution Methods 0.000 abstract description 2
- 239000012895 dilution Substances 0.000 abstract description 2
- 239000000284 extract Substances 0.000 abstract 1
- 239000003570 air Substances 0.000 description 22
- 239000012080 ambient air Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000003446 memory effect Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
- G01N1/26—Devices for withdrawing samples in the gaseous state with provision for intake from several spaces
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0078—Testing material properties on manufactured objects
- G01N33/0081—Containers; Packages; Bottles
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Engineering & Computer Science (AREA)
- Molecular Biology (AREA)
- Biomedical Technology (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
For the extraction of a gas sample from a container (1) a gas flow (3) is introduced into the container, expelling from the container gas contained therein. The expelled gas (5) is introduced into a collecting chamber (4) with an inflow opening larger than the outflow opening. Above the outflow opening, a suction pipe (7) extracts a portion (8) of the gas flow expelled from the container and supplies it to an analysing station for analysis. This method and arrangement enable the expelled gas flow to be utilized for a longer time without significant dilution, thus affording better conditions for analysis.
Description
218627~
METHOD AND APPARATUS FOR TAKING GAS SAMPLES FROM CONTAINERS
The invention relates to a method for taking a gas sample from containers carried past a sampling station by means of a conveyor device, in which a medium is injected into each container and the gas thereby expelled from the container is at least partially received into a throughflow collecting chamber and drawn off to at least one analysing unit. The invention also relates to an apparatus for carrying out the method, according to the introductory part of claim 9.
A method as described above, and such apparatus are known from DE-C 4225984. This is intended to provide a simple way of taking a gas sample from eontainers, in particular from returned multi-trip bottles. With the method and apparatus according to the prior art, however, the mechanical simplification which the invention sets out to, and does, achieve is associated with a very short gas withdrawal time, and this may have unsatisfaetory results, especially if the bottles are being conveyed at high speed.
WO-A 93/24841 discloses a method and an apparatus in which the same problems basically occur.
The later-published DE-A 4427314 discloses an arrangement in which there is no extraction from a collecting chamber, the expelled gas being conveyed directly through a conduit to a measuring cell, and then being released to atmosphere.
Accordingly a principal object of the present 21~6~75 , invention is to improve the known method so that gas samples for analysis can be reliably taken even under difficult conditions, for example with a high bottle throughput.
This object may be realised in the abovementioned method by effecting the inflow of gas into the collecting chamber over a longer section of the conveyor path than is required for the outflow of gas from the collecting chamber.
It has been found that the problem indicated can be solved by such a step, in which the gas expelled from the container is collected over a relatively extended section of the conveyor path and is focussed on a relatively small space in the region of the outflow opening. For each container, the gas sample ~xpelled from the container by the injected air is available over a section of the conveyor path, not just at a specific point on the conveyor path as in the prior art.
Also, extraction of the gas sample is advantageously effected above the outflow opening of the collecting chamber. This ensures that the flow of the gas which has been collected in the chamber is not disturbed by the extraction element, which is optimally positioned within the gas flow, thus assisting extraction of a gas sample suitable for analysis.
It is also advantageous if injection of the medium (usually compressed air) likewise takes place over a section of the conveyor path, whicll may be of the same 2186~75 length as, or longer than, the inflow opening of the collecting chamber. Shorter injection is also possible, but is not preferred.
The apparatus for carrying out the method has the characterising features of claim 9, in order to realise the abovestated object.
The invention will now be described in detail with reference to the embodiments illustrated by way of example in the drawings, in which:
Fig. 1 shows schematically the neck and mouth region of a bottle, to illustrate the method:
Fig. 2a shows schematically a collecting chamber according to the invention, viewed in side elevation, Fig. 2b shows schematically the arrangement of Fig. 2a, viewed in the conveying direction, Fig. 3 is a perspective view of the collecting chamber with its injection nozzle, Fig. 4 is a schematic illustration of a purging air arrangement, Fig. 5 is a diagram showing the effect of the purging air, and Fig. 6 is a view of the mouth region of a container illustrating another air and gas flow arrangement.
Fig. 1 shows schematically the upper part of a container 1, eg. a bottle. The injection of a jet 3 of rnedium into this container by rneans of a nozzle 2 is known from the state of the art. The mediurn will usually be air, 2 i 8~275 although some other gaseous medium may also be used. The medium is injected over part of the cross-section of the opening of the container 1. As is also known, the injection of the medium causes the gas present in the bottle to be expelled through displacement by the injected medium. For a certain time this expulsion takes place with practically no dilution by the injected medium. In Fig. 1 the expelled gas is illustrated as a flow 5. It is also known that this flow 5 can be collected in a round collector pipe and part of this gas flow can be extracted from the interior of the collector pipe in order that the gas can be analysed for residues and a judgement made as to the reusability of the container. The containers 1 are conveyed on a conveyor device and pass a sampling station where the gas flow 5 passes into the collector pipe at a point location.
In accordance with the present invention, the intake of the gas expelled from the bottle 1 occurs not at a single point on the conveyor path but over an extended section thereof which is longer than the gas outflow opening at the top of the collecting chamber. In Figs. 2a and 2b this is illustrated schematically, with Fig. 2a showing a side view of the collecting chamber, the bottles being conveyed in the direction of the arrow B on a known conveyor device which is not shown, while in Fig. 2b the same collecting chamber 4 is viewed in the direction of the arrow A in Fig. 2a, that is to say in the conveying direction of the containers.
2 ~ 86~75 In Fig. 2a a container 1 is shown in three different positions through which it passes as it is being conveyed past the collecting chamber. The three positions illustrated are designated 1,1' and 1". The gas flows escaping from the container in these positions are accordingly designated 5,5' and 5". In Fig. 2a the medium injected into the bottles is not shown. However, this will be apparent from Fig. 2b, which will be explained presently. From Fig. 2a, it can be seen that the collecting chamber 4 has an inflow opening 14 for the gas flows 5 which extends over a larger section of the conveyor path than the outflow opening 13 for the gas flows escaping from the collecting chamber, which are designated 5"'. In the example shown, the collecting chamber 4 is bounded by two baffle elements or collector elements constructed eg.
as deflector plates 10 and 11 whose bottom ends are further apart from each other than their top ends, those bottom and top ends defining the inflow opening 14 and the outflow opening 13 respectively. The collecting chamber may be closed off on one side with a wall 12, or closed off with walls on both sides, or open on both sides.
It can be seen that the configuration of the collecting chamber in this embodiment of the invention allows the gas escaping from an individual container 1 to be collected over a conveying distance b. It has been found that a gas flow 5 which is essentially undiluted by the injected medium, flows out of the bottle for a sufficient enough length of time. The specified ~1 8~275 .
configuration of the collecting chamber 4 causes the gas flows 5,5' and 5" from the bottle to be focussed at the outflow opening 13 of the collecting chamber. The gas flow at the outflow opening is designated 5"'. The configuration of the collecting chamber 4 has also been found to cause the gas flow 5 to be only slight]y diluted with ambient air, as essentially only air expelled from the container is conveyed through the collecting chamber 4 to the outflow opening 13.
The portion of the gas flow which is to be supplied to the analysing unit is preferably extracted above the outflow opening 13. For this purpose, a suction pipe 7 is provided, which draws off part of the gas flow 5"' and supplies it as a flow 8 to an analysing unit, which is not shown. This arrangement for the extraction of the sample gas flow 8 above the collecting chamber 4 has the advantage that there is no disturbance of the flow in the collecting chamber itself, thus further avoiding the ingress of ambient air. The sample gas flows 5,5' and 5"
are focussed at the outflow opening 13 of the collecting chamber 4, whose outlet diameter a is small in relation to the distance b, so that the gas sample 8 removed above the opening 13 is a representative, only slightly diluted, sample of gas from the container 1, and is available for analysis during a time span which is prolonged by approximately the ratio b : a.
The injection - not illustrated in Fig. 2a - of the jet 3 of compressed air to displace the gas present in 21 86~75 the container can be seen in detail in Fig. 2b. The nozzle 2 to introduce the compressed air jet 3 is, accordingly, located behind the collecting chamber 4, in the direction of view of Fig. 2a. The nozzle 2 is preferably a nozzle which extends over the entire length b of the inflow opening of the collecting chamber 4. The nozzle 2 may, however, be longer than the distance b, so that injection commences before the bottle mouth arrives in the region of the collecting chamber 4. It is also possible to make the nozzle 2 shorter than the distancè b if this should prove advantageous for a particular application. In the illustration in Fig. 2b, the reference symbols used in Fig.
2a designate the same parts.
Fig. 3 shows a perspective view of a similar configuration to Figs. 2a and 2b of the apparatus for carrying out the method. The mouth of a container 1, which is being conveyed in the direction of the arrow B, is again shown. The collecting chamber 4, again bounded by two deflector plates 10 and 11, and also having a back wall 12, is arranged above the container 1. For its part, the back wall 12 forms part of the air nozzle 2, which is constructed with a slit-form opening 15 producing a flow 3 in the form of an air curtain entering the container 1 throughout the time during which the container is being conveyed under the collecting chamber 4. For the sake of clarity, the gas 5 flowing out of the container 1 is illustrated only at the container mouth in ~ig. 3, and not inside the collectiny chamber. The pattern of gas flow is, 2 1 86~75 .
however, essentially as illustrated in Fig. 2a. An extraction element 7, which is shown removing part of the gas flow 5 as a flow 8, and which feeds the flow to the analysing station, is located above the outflow opening of the collecting chamber 4. In the example shown, air outlet openings 16 are also illustrated in the side wall 12; the function of these openings will be explained presently.
The embodiment shown in Fig. 3 may be modified in a variety of ways. For example, the shape of the deflector plates 10 and 11 may be other than rectangular as illustrated. Furthermore, instead of being straight, these deflector plates may be curved, with the convex side towards the container mouth or facing the other way. Also, as already mentioned, the back wall 12 of the collecting chamber is not obligatory. The collecting chamber could be open at the rear, as well as at the front. In this case, the air supply to the nozzle 2 would be close to its discharge opening 15, and not above the deflector plates 10 and 11. If the back wall 12 were omitted, the deflector plates would be secured above the conveyor device by other means, eg. by supporting bars. In all embodiments, the flow and/or pressure of the medium 3 is either set at a constant level or varied to suit operating parameters, such as the conveying speed for example.
The entire apparatus forming the collecting chamber and extractor is moreover preferably made vertically adjustable so that the height of the sampling station above the conveyor device can be adjusted to adapt 21 ~6275 the apparatus to different containers. The slit form opening 15 of the nozzle 2 may be replaced with a series of individual openings. In this case, instead of the continuous injection resulting from an unbroken air curtain (which is preferred), a series of continuously flowing air columns, arranged side by side, are formed, whose effect on the passing bottle is that of a pulsed injection.
Furthermore it is possible to provide not ~ust a single nozzle for injection into one segment of the circular area of the mouth, but two nozzles, injecting into two segments.
Such a method of injection is shown schematically in Fig.
6, in which one nozzle produces an air curtain 3 injecting into the segment 18 of the circular mouth of the container 1 (as is also the case in Fig~ 3), and an additional nozzle now injects an air curtain 3' into a segment 19. The emerging gas flow 5 will then lie centrally between the two air curtains 3 and 3'. A corresponding modification of eg.
the embodiment shown in Fig. 3 is easily realised. of course, another arrangement, in which the injection is made centrally, is also possible, with a nozzle e~tending above the centre of the circular opening of the container, and with gas 5 passing via lateral segments into the collecting chamber. In this case, if the need arises, there may be provided two separate collecting chambers which join together in the region of their outflow opening. The entire gas sampling unit can moreover be heated to prevent gas from the containers from condensing on the unit.
A further embodiment will now be described with 2~6275 reference to Fig. 4. In Fig. 4, the collecting chamber 4 is again illustrated schematically, and bounded by deflector plates 10 and 11, with the extractor pipe 7 arranged at its outflow opening. Here the gas emerging from the container 1 is illustrated by an arrow 25 drawn as a broken line which represents the normal direction of the gas outflow. In the embodiment of Fig. 4, a purging airflow 17 is produced approximately at right angles to the conveying direction of the containers, causing a slight deflection of the gas outflow from the bottle 1. The gas flow which is actually established as a result of the crossflow 17 is indicated by the arrow 5 drawn as an unbroken line. This gas flow also reaches the extractor pipe 7, that is to say, the flow 17 is made sufficiently weak to ensure that the gas flow 5 stays within the collecting chamber. The purpose of this purging airflow 17 is to purge the gas collecting chamber 4 before the arrival of the next bottle 1 sufficiently to ensure that when the next bottle 1 releases its gas flow into the collecting chamber only insignificant amounts of the gas flow from the previous container remain in the collecting chamber, in order that the analysis is not vitiated by the so-called memory effect of the collecting chamber.
Fig. 5 shows as an example the output signal of an analysing station which analyses the extracted gas flow, over time t. The curve 20 represents the output signal yielded by analysis of the gas flow of a first container, whi:le the output signal 20' is the signal yielded by 21 ~6275 analysis of the following container. The curve 20 shows the profile of the signal obtained without the use of the purging air flow. It will be seen that in that period t2, when the following container is being analysed and the output signal 20' is being generated on the basis of the gas outflow from that container, signal components 22 originating from the gas flow of the container previously analysed in the period tl are still being detected. With the use of purging air, the resulting curve is not curve 20, but curve 21, from which it is apparent that the gas components from the previous container have largely been purged away by the period t2, so that they will not have an unacceptable influence on the analysis of the contents of the second container.
The pu;-ging airflow 17 may be produced by a separate blower or a separate compressed air connection.
The velocity and rate of the purging airflow are preferably adapted to the specific container conveying speed and/or container type Fig. 3 shows the air out]et openings 16 (already referred to) in the back wall 12 of the collecting chamber, which are used in this example to produce the transverse purging airflow. The purging airflow is in this example drawn directly from the injection airflow 3, and diverted into the collecting chamber.
METHOD AND APPARATUS FOR TAKING GAS SAMPLES FROM CONTAINERS
The invention relates to a method for taking a gas sample from containers carried past a sampling station by means of a conveyor device, in which a medium is injected into each container and the gas thereby expelled from the container is at least partially received into a throughflow collecting chamber and drawn off to at least one analysing unit. The invention also relates to an apparatus for carrying out the method, according to the introductory part of claim 9.
A method as described above, and such apparatus are known from DE-C 4225984. This is intended to provide a simple way of taking a gas sample from eontainers, in particular from returned multi-trip bottles. With the method and apparatus according to the prior art, however, the mechanical simplification which the invention sets out to, and does, achieve is associated with a very short gas withdrawal time, and this may have unsatisfaetory results, especially if the bottles are being conveyed at high speed.
WO-A 93/24841 discloses a method and an apparatus in which the same problems basically occur.
The later-published DE-A 4427314 discloses an arrangement in which there is no extraction from a collecting chamber, the expelled gas being conveyed directly through a conduit to a measuring cell, and then being released to atmosphere.
Accordingly a principal object of the present 21~6~75 , invention is to improve the known method so that gas samples for analysis can be reliably taken even under difficult conditions, for example with a high bottle throughput.
This object may be realised in the abovementioned method by effecting the inflow of gas into the collecting chamber over a longer section of the conveyor path than is required for the outflow of gas from the collecting chamber.
It has been found that the problem indicated can be solved by such a step, in which the gas expelled from the container is collected over a relatively extended section of the conveyor path and is focussed on a relatively small space in the region of the outflow opening. For each container, the gas sample ~xpelled from the container by the injected air is available over a section of the conveyor path, not just at a specific point on the conveyor path as in the prior art.
Also, extraction of the gas sample is advantageously effected above the outflow opening of the collecting chamber. This ensures that the flow of the gas which has been collected in the chamber is not disturbed by the extraction element, which is optimally positioned within the gas flow, thus assisting extraction of a gas sample suitable for analysis.
It is also advantageous if injection of the medium (usually compressed air) likewise takes place over a section of the conveyor path, whicll may be of the same 2186~75 length as, or longer than, the inflow opening of the collecting chamber. Shorter injection is also possible, but is not preferred.
The apparatus for carrying out the method has the characterising features of claim 9, in order to realise the abovestated object.
The invention will now be described in detail with reference to the embodiments illustrated by way of example in the drawings, in which:
Fig. 1 shows schematically the neck and mouth region of a bottle, to illustrate the method:
Fig. 2a shows schematically a collecting chamber according to the invention, viewed in side elevation, Fig. 2b shows schematically the arrangement of Fig. 2a, viewed in the conveying direction, Fig. 3 is a perspective view of the collecting chamber with its injection nozzle, Fig. 4 is a schematic illustration of a purging air arrangement, Fig. 5 is a diagram showing the effect of the purging air, and Fig. 6 is a view of the mouth region of a container illustrating another air and gas flow arrangement.
Fig. 1 shows schematically the upper part of a container 1, eg. a bottle. The injection of a jet 3 of rnedium into this container by rneans of a nozzle 2 is known from the state of the art. The mediurn will usually be air, 2 i 8~275 although some other gaseous medium may also be used. The medium is injected over part of the cross-section of the opening of the container 1. As is also known, the injection of the medium causes the gas present in the bottle to be expelled through displacement by the injected medium. For a certain time this expulsion takes place with practically no dilution by the injected medium. In Fig. 1 the expelled gas is illustrated as a flow 5. It is also known that this flow 5 can be collected in a round collector pipe and part of this gas flow can be extracted from the interior of the collector pipe in order that the gas can be analysed for residues and a judgement made as to the reusability of the container. The containers 1 are conveyed on a conveyor device and pass a sampling station where the gas flow 5 passes into the collector pipe at a point location.
In accordance with the present invention, the intake of the gas expelled from the bottle 1 occurs not at a single point on the conveyor path but over an extended section thereof which is longer than the gas outflow opening at the top of the collecting chamber. In Figs. 2a and 2b this is illustrated schematically, with Fig. 2a showing a side view of the collecting chamber, the bottles being conveyed in the direction of the arrow B on a known conveyor device which is not shown, while in Fig. 2b the same collecting chamber 4 is viewed in the direction of the arrow A in Fig. 2a, that is to say in the conveying direction of the containers.
2 ~ 86~75 In Fig. 2a a container 1 is shown in three different positions through which it passes as it is being conveyed past the collecting chamber. The three positions illustrated are designated 1,1' and 1". The gas flows escaping from the container in these positions are accordingly designated 5,5' and 5". In Fig. 2a the medium injected into the bottles is not shown. However, this will be apparent from Fig. 2b, which will be explained presently. From Fig. 2a, it can be seen that the collecting chamber 4 has an inflow opening 14 for the gas flows 5 which extends over a larger section of the conveyor path than the outflow opening 13 for the gas flows escaping from the collecting chamber, which are designated 5"'. In the example shown, the collecting chamber 4 is bounded by two baffle elements or collector elements constructed eg.
as deflector plates 10 and 11 whose bottom ends are further apart from each other than their top ends, those bottom and top ends defining the inflow opening 14 and the outflow opening 13 respectively. The collecting chamber may be closed off on one side with a wall 12, or closed off with walls on both sides, or open on both sides.
It can be seen that the configuration of the collecting chamber in this embodiment of the invention allows the gas escaping from an individual container 1 to be collected over a conveying distance b. It has been found that a gas flow 5 which is essentially undiluted by the injected medium, flows out of the bottle for a sufficient enough length of time. The specified ~1 8~275 .
configuration of the collecting chamber 4 causes the gas flows 5,5' and 5" from the bottle to be focussed at the outflow opening 13 of the collecting chamber. The gas flow at the outflow opening is designated 5"'. The configuration of the collecting chamber 4 has also been found to cause the gas flow 5 to be only slight]y diluted with ambient air, as essentially only air expelled from the container is conveyed through the collecting chamber 4 to the outflow opening 13.
The portion of the gas flow which is to be supplied to the analysing unit is preferably extracted above the outflow opening 13. For this purpose, a suction pipe 7 is provided, which draws off part of the gas flow 5"' and supplies it as a flow 8 to an analysing unit, which is not shown. This arrangement for the extraction of the sample gas flow 8 above the collecting chamber 4 has the advantage that there is no disturbance of the flow in the collecting chamber itself, thus further avoiding the ingress of ambient air. The sample gas flows 5,5' and 5"
are focussed at the outflow opening 13 of the collecting chamber 4, whose outlet diameter a is small in relation to the distance b, so that the gas sample 8 removed above the opening 13 is a representative, only slightly diluted, sample of gas from the container 1, and is available for analysis during a time span which is prolonged by approximately the ratio b : a.
The injection - not illustrated in Fig. 2a - of the jet 3 of compressed air to displace the gas present in 21 86~75 the container can be seen in detail in Fig. 2b. The nozzle 2 to introduce the compressed air jet 3 is, accordingly, located behind the collecting chamber 4, in the direction of view of Fig. 2a. The nozzle 2 is preferably a nozzle which extends over the entire length b of the inflow opening of the collecting chamber 4. The nozzle 2 may, however, be longer than the distance b, so that injection commences before the bottle mouth arrives in the region of the collecting chamber 4. It is also possible to make the nozzle 2 shorter than the distancè b if this should prove advantageous for a particular application. In the illustration in Fig. 2b, the reference symbols used in Fig.
2a designate the same parts.
Fig. 3 shows a perspective view of a similar configuration to Figs. 2a and 2b of the apparatus for carrying out the method. The mouth of a container 1, which is being conveyed in the direction of the arrow B, is again shown. The collecting chamber 4, again bounded by two deflector plates 10 and 11, and also having a back wall 12, is arranged above the container 1. For its part, the back wall 12 forms part of the air nozzle 2, which is constructed with a slit-form opening 15 producing a flow 3 in the form of an air curtain entering the container 1 throughout the time during which the container is being conveyed under the collecting chamber 4. For the sake of clarity, the gas 5 flowing out of the container 1 is illustrated only at the container mouth in ~ig. 3, and not inside the collectiny chamber. The pattern of gas flow is, 2 1 86~75 .
however, essentially as illustrated in Fig. 2a. An extraction element 7, which is shown removing part of the gas flow 5 as a flow 8, and which feeds the flow to the analysing station, is located above the outflow opening of the collecting chamber 4. In the example shown, air outlet openings 16 are also illustrated in the side wall 12; the function of these openings will be explained presently.
The embodiment shown in Fig. 3 may be modified in a variety of ways. For example, the shape of the deflector plates 10 and 11 may be other than rectangular as illustrated. Furthermore, instead of being straight, these deflector plates may be curved, with the convex side towards the container mouth or facing the other way. Also, as already mentioned, the back wall 12 of the collecting chamber is not obligatory. The collecting chamber could be open at the rear, as well as at the front. In this case, the air supply to the nozzle 2 would be close to its discharge opening 15, and not above the deflector plates 10 and 11. If the back wall 12 were omitted, the deflector plates would be secured above the conveyor device by other means, eg. by supporting bars. In all embodiments, the flow and/or pressure of the medium 3 is either set at a constant level or varied to suit operating parameters, such as the conveying speed for example.
The entire apparatus forming the collecting chamber and extractor is moreover preferably made vertically adjustable so that the height of the sampling station above the conveyor device can be adjusted to adapt 21 ~6275 the apparatus to different containers. The slit form opening 15 of the nozzle 2 may be replaced with a series of individual openings. In this case, instead of the continuous injection resulting from an unbroken air curtain (which is preferred), a series of continuously flowing air columns, arranged side by side, are formed, whose effect on the passing bottle is that of a pulsed injection.
Furthermore it is possible to provide not ~ust a single nozzle for injection into one segment of the circular area of the mouth, but two nozzles, injecting into two segments.
Such a method of injection is shown schematically in Fig.
6, in which one nozzle produces an air curtain 3 injecting into the segment 18 of the circular mouth of the container 1 (as is also the case in Fig~ 3), and an additional nozzle now injects an air curtain 3' into a segment 19. The emerging gas flow 5 will then lie centrally between the two air curtains 3 and 3'. A corresponding modification of eg.
the embodiment shown in Fig. 3 is easily realised. of course, another arrangement, in which the injection is made centrally, is also possible, with a nozzle e~tending above the centre of the circular opening of the container, and with gas 5 passing via lateral segments into the collecting chamber. In this case, if the need arises, there may be provided two separate collecting chambers which join together in the region of their outflow opening. The entire gas sampling unit can moreover be heated to prevent gas from the containers from condensing on the unit.
A further embodiment will now be described with 2~6275 reference to Fig. 4. In Fig. 4, the collecting chamber 4 is again illustrated schematically, and bounded by deflector plates 10 and 11, with the extractor pipe 7 arranged at its outflow opening. Here the gas emerging from the container 1 is illustrated by an arrow 25 drawn as a broken line which represents the normal direction of the gas outflow. In the embodiment of Fig. 4, a purging airflow 17 is produced approximately at right angles to the conveying direction of the containers, causing a slight deflection of the gas outflow from the bottle 1. The gas flow which is actually established as a result of the crossflow 17 is indicated by the arrow 5 drawn as an unbroken line. This gas flow also reaches the extractor pipe 7, that is to say, the flow 17 is made sufficiently weak to ensure that the gas flow 5 stays within the collecting chamber. The purpose of this purging airflow 17 is to purge the gas collecting chamber 4 before the arrival of the next bottle 1 sufficiently to ensure that when the next bottle 1 releases its gas flow into the collecting chamber only insignificant amounts of the gas flow from the previous container remain in the collecting chamber, in order that the analysis is not vitiated by the so-called memory effect of the collecting chamber.
Fig. 5 shows as an example the output signal of an analysing station which analyses the extracted gas flow, over time t. The curve 20 represents the output signal yielded by analysis of the gas flow of a first container, whi:le the output signal 20' is the signal yielded by 21 ~6275 analysis of the following container. The curve 20 shows the profile of the signal obtained without the use of the purging air flow. It will be seen that in that period t2, when the following container is being analysed and the output signal 20' is being generated on the basis of the gas outflow from that container, signal components 22 originating from the gas flow of the container previously analysed in the period tl are still being detected. With the use of purging air, the resulting curve is not curve 20, but curve 21, from which it is apparent that the gas components from the previous container have largely been purged away by the period t2, so that they will not have an unacceptable influence on the analysis of the contents of the second container.
The pu;-ging airflow 17 may be produced by a separate blower or a separate compressed air connection.
The velocity and rate of the purging airflow are preferably adapted to the specific container conveying speed and/or container type Fig. 3 shows the air out]et openings 16 (already referred to) in the back wall 12 of the collecting chamber, which are used in this example to produce the transverse purging airflow. The purging airflow is in this example drawn directly from the injection airflow 3, and diverted into the collecting chamber.
Claims (16)
1. Method for taking a gas sample from containers (1) carried past a sampling station by means of a conveyor device, in which a medium (3) is injected into each container and the gas (5) thereby expelled from the container is at least partially received into a throughflow collecting chamber (4) and drawn off to at least one analysing unit, characterised in that the inflow of gas into the collecting chamber is effected over a longer section of the conveyor path than is required for the outflow of gas (5"') from the collecting chamber.
2. Method according to claim 1, characterised in that the inflow is effected via an inflow opening (14) of the collecting chamber (4) that is elongated essentially parallel to the conveyor device.
3. Method according to claim 1 or 2, characterised in that the gas is extracted from above an opening (13) provided in the collecting chamber for said outflow of gas.
4. Method according to claim 1 or 2, characterised in that the medium is injected for essentially as long as, or longer than, the time during which the container opening is in register with the inflow opening of the collecting chamber.
5. Method according to claim 1 or 2, characterised in that the medium is injected in the form of an air curtain extending parallel with the container conveying direction.
6. Method according to claim 1 or 2, characterised in that injection of medium is continuous or pulsed.
7. Method according to claim 1 or 2, characterised in that the flow and/or pressure of the medium is set at a constant level or is varied to suit at least one operating parameter, such as in particular the container type, size, and conveying speed.
8. Method according to claim 1 or 2, characterised in that a purging flow (17) is introduced into the collecting chamber essentially at right angles to the conveying direction.
9. Apparatus for taking a gas sample from containers (1), comprising a conveyor device for the containers and a sampling station, the containers being transportable by means of the conveyor device past the sampling station, in which a medium (3) can be injected into each container (1) by means of an injection arrangement and the gas thereby expelled from the container can be received in a throughflow collecting chamber (4), and including a suction pipe (7) for supplying a portion (8) of the gas to an analysing unit, characterised in that the inflow opening (14) of the collecting chamber facing towards the conveyor device is larger than the outflow opening (13).
10. Apparatus according to claim 9, characterised in that the inflow opening (14) is in the form of an opening that is elongated essentially parallel to the conveyor device.
11. Apparatus according to claim 9 or 10, characterised in that the suction pipe (7) is arranged above an outflow opening (13) of the collecting chamber.
12. Apparatus according to claim 9 or 10, characterised in that the injection arrangement has at least one slit-form nozzle (2,15).
13. Apparatus according to claim 12, characterised in that the slit-form nozzle is arranged alongside the inflow opening (14) of the collecting chamber and its length is essentially the same as, or greater than, the length of the said inflow opening.
14. Apparatus according to claim 9, 10 or 13, characterised in that the collecting chamber is formed by two opposing deflector plates (10,11) forming part of the surface of a truncated pyramid.
15. Apparatus according to claim 14, characterised in that the collecting chamber also has at least one side wall (12) connecting the deflector plates (10,11).
16. Apparatus according to claim 9, 10, 13 or 15, characterised in that a device is provided for producing within the collecting chamber (4) a purging flow (17) essentially at right angles to the conveying direction.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH02824/95 | 1995-10-06 | ||
| CH282495 | 1995-10-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2186275A1 true CA2186275A1 (en) | 1997-04-07 |
Family
ID=4242433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002186275A Abandoned CA2186275A1 (en) | 1995-10-06 | 1996-09-23 | Method and apparatus for taking gas samples from containers |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0767368A3 (en) |
| JP (1) | JPH09126962A (en) |
| CN (1) | CN1158417A (en) |
| AR (1) | AR003760A1 (en) |
| BR (1) | BR9603989A (en) |
| CA (1) | CA2186275A1 (en) |
| NO (1) | NO964224L (en) |
| PL (1) | PL316404A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680043B (en) * | 2016-11-21 | 2020-07-31 | 北京蓝色星语科技有限公司 | Disturbance sampling device and method for biochemical harmful factors |
| CN117825223B (en) * | 2024-03-05 | 2024-05-31 | 中汽研汽车检验中心（天津）有限公司 | Brake abrasion particulate matter testing system and method based on chassis dynamometer |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4150574A (en) * | 1977-12-28 | 1979-04-24 | Harry Wolf | Fluid sampling system |
| US5352611A (en) * | 1992-06-01 | 1994-10-04 | The Coca-Cola Company | Method and system for sampling and determining the presence of compounds in containers |
| DE4225984C2 (en) * | 1992-08-06 | 1995-06-01 | Khs Masch & Anlagenbau Ag | Method and device for taking air samples from containers |
| DE4427314C2 (en) * | 1994-08-02 | 1997-02-20 | Graessle Walter Gmbh | Device for examining containers for foreign gases |
-
1996
- 1996-09-03 EP EP96114045A patent/EP0767368A3/en not_active Withdrawn
- 1996-09-23 CA CA002186275A patent/CA2186275A1/en not_active Abandoned
- 1996-10-01 AR ARP960104563A patent/AR003760A1/en unknown
- 1996-10-02 JP JP8262079A patent/JPH09126962A/en active Pending
- 1996-10-04 CN CN96113432.1A patent/CN1158417A/en active Pending
- 1996-10-04 BR BR9603989A patent/BR9603989A/en not_active Application Discontinuation
- 1996-10-04 PL PL96316404A patent/PL316404A1/en unknown
- 1996-10-04 NO NO964224A patent/NO964224L/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| EP0767368A2 (en) | 1997-04-09 |
| PL316404A1 (en) | 1997-04-14 |
| CN1158417A (en) | 1997-09-03 |
| BR9603989A (en) | 1998-06-09 |
| MX9604524A (en) | 1997-07-31 |
| NO964224L (en) | 1997-04-07 |
| JPH09126962A (en) | 1997-05-16 |
| NO964224D0 (en) | 1996-10-04 |
| EP0767368A3 (en) | 1998-06-03 |
| AR003760A1 (en) | 1998-09-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| USRE33492E (en) | Apparatus for cooling and granulation of thermoplastic strands | |
| US4578092A (en) | Method and apparatus for improving the operation of a dust collector | |
| KR100192741B1 (en) | Method and system for sampling and determining the presence of compounds in containers | |
| US4053292A (en) | Gas scrubbing plant | |
| JP4714486B2 (en) | Method and apparatus for separating foreign matter | |
| US4018580A (en) | Separator for separating liquid droplets from a stream of gas | |
| KR870010227A (en) | Improved Apparatus and Methods for Melt Spinning | |
| KR890017515A (en) | Method and apparatus for drying a liquid layer attached to a moving carrier | |
| US4666472A (en) | Dust collector with deflector means | |
| GB2465468A (en) | An apparatus for removing impurities from between textile fibres in a spinning room | |
| KR970010163B1 (en) | Dust collector having hollow filter | |
| US4789387A (en) | Dust collector | |
| CA2186275A1 (en) | Method and apparatus for taking gas samples from containers | |
| US3820307A (en) | Apparatus for scrubbing waste gases | |
| JPH11514095A (en) | A device for measuring the mass of a flowing medium | |
| US5846300A (en) | Fabric filter with gas inlet geometry and method | |
| US4785504A (en) | Suction duct for the pneumatic removal of fiber tufts detached by a bale opener | |
| MXPA96004524A (en) | Method and apparatus for taking recipient gas samples | |
| JPH0423737B2 (en) | ||
| US4024208A (en) | Device for carrying out physical and/or chemical reactions between liquids and gases | |
| KR930011913A (en) | Method and apparatus for tobacco drying and expansion | |
| JPH0777487A (en) | Inspection method and inspection unit for dust collecting device | |
| US4285703A (en) | Apparatus for cleaning gas | |
| JPH08103616A (en) | Moving pulse jet type bag filter | |
| SE7909078L (en) | DEVICE FOR CLEANING GASES BY MEASUREMENT |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |
Effective date: 19990923 |