Patent Application
20070091326
The present application claims priority under 35 U.S.C. §119 of German Patent Application No. 10 2005 046 581.1, filed on Sep. 28, 2005, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention
The invention relates to a device for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry, an illumination device and a photodetector being provided, whereby an illumination essentially uniform in a longitudinally axial manner of at least one section of a multi-segment filter or a combination of filter segments is rendered possible by means of the illumination device. The invention furthermore relates to a method for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry.
2. Discussion of Background Information
Various errors can occur in the production of multi-segment filters, upstream of which an assembly of filter segments is usually arranged, such as, e.g., transposed filter segments or filter components, a missing filter segment, an incorrect position or the insertion of a filter segment with an incorrect length, a gap between filter segments and, e.g., a filter segment, the longitudinal axis of which is tilted with respect to the other filter segments, e.g., by 90°.
Known devices and methods for measuring properties of multi-segment filters or combinations of filter segments or methods for quality assurance of multi-segment filters or combinations of filter segments are used to try and detect such errors and to eject the then defective multi-segment filters or combinations of filter segments from further processing, so that, e.g., no defective filter cigarettes are produced. Multi-segment filters are usually filters that are assembled from different filter materials, such as, e.g., acetate filter segments, cellulose filter segments, filter segments containing granular material, e.g., comprising activated charcoal granular material and the like.
A device for measuring properties of multi-segment filters of the tobacco-processing industry with the transmission method is known from WO 03/055338 A2, an illumination device and a photodetector being provided, whereby an irradiation essentially uniform in a longitudinally axial manner of a multi-segment filter is rendered possible by means of the illumination device, whereby the photodetector is arranged inside a conveyor element that is provided to convey at least multi-segment filters. Moreover, from this document a system is known for measuring properties of rod-shaped articles or of components of rod-shaped articles of the tobacco-processing industry which can be subsequently joined together to form a rod-shaped article, in particular of multi-segment filters and/or filter cigarettes provided with multi-segment filters, whereby a first measuring device is provided, by means of which the articles or components of the articles can be measured with a reflection method, whereby a second measuring device is provided by means of which the articles or components of the articles can be measured with a transmission method.
The present invention provides a method and device with increased measurement precision to increase the quality control of multi-segment filters or combinations of filter segments and the filter cigarettes to be formed therefrom.
According to the invention, a device is provided for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry. An illumination device and a photodetector are provided, in which an illumination essentially uniform in a longitudinally axial manner of at least one section of a multi-segment filter or a combination of filter segments is rendered possible by the illumination device. In this manner, the illumination device images a first line of electromagnetic radiation on the multi-segment filters or combinations of filter segments of the tobacco-processing industry, the extension of which transverse to the longitudinal axis of the multi-segment filter or the combination of filter segments is smaller than the diameter of the multi-segment filter or the combination of filter segments.
Longitudinally axial areas of the multi-segment filters or the combination of filter segments can be illuminated in a very targeted manner through the device according to the invention. In this way, the areas can be those which ensure a high contrast for the respective filter segments, so that the quality of the measurement is improved. In particular, a higher contrast in the measurement can be generated through the device according to the invention, which leads to more precise measurement results.
Within the scope of this invention, imaging a first line also refers to, in particular, shining on, illuminating, and the like. The electromagnetic radiation is preferably light. Within the scope of the invention, longitudinally axial means along the axis of the multi-segment filters or the combination of filter segments or the respective filter segments, which are usually circular or elliptical in cross section. Thus, longitudinally axial means essentially perpendicular to the cross section of these segments or the filters. Longitudinally axial also means in particular that the first line can lie on the surface of the multi-segment filters or the combination of filter segments. Multi-segment filters or combinations of filter segments are also understood in particularly to be multi-segment filters or combinations of filter segments provided with wrapping material. The properties of multi-segment filters or the combination of filter segments can also be measured on a filter cigarette. The device according to the invention is therefore also suitable in particular for measuring the multi-segment filters or the combination of filter segments in finished filter cigarettes.
A particularly precise measurement is possible if the extension of the first line transverse to the longitudinal axis of the multi-segment filter or the combination of filter segments is less than half, in particular less than a quarter, in particular less than one eighth of the diameter of the multi-segment filter or the combination of filter segments or of the diameter of a filter segment. The extension of the first line can be, e.g., between 0.5 mm and 2 mm. The illumination device is preferably a linear laser.
According to the invention, a device is provided for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry. An illumination device and a photodetector are provided. An illumination essentially uniform in a longitudinally axial manner of at least one section of a multi-segment filter or a combination of filter segments is possible by the illuminating device, and the photodetector includes an optical system that images a second line in a longitudinally axial manner on the multi-segment filter or the combination of filter segments. The second line hereby also preferably has an extension that is smaller transverse to the longitudinal axis of the multi-segment filter or the combination of filter segments than the diameter (D) of the multi-segment filter or the combination of filter segments. The extension can also be less than half, in particular less than a quarter, in particular less than an eighth of the diameter (D) of the multi-segment filter or the combination of filter segments and can preferably be in a range of 0.5 mm to 5 mm, and preferably in a range of 0.5 mm to 2 mm. Through the device according to the invention, it is possible to scan in a very targeted manner corresponding longitudinally axial regions of the multi-segment filters or the combinations of filter segments or the surface of the multi-segment filters or the combinations of filter segments or to measure whether the desired properties are present.
Within the scope of the invention, imaging a second line refers to, in particular, recording an image of the line or detecting the brightness of the line or the color(s). To this end, an optical system can be imaged a second line on a detector that is sensitive to the electromagnetic radiation.
If the second line is arranged to the edge of the multi-segment filter or the combination of filter segments, particular defects can be ascertained very efficiently, such as, e.g., a tipping of filter segments with respect to other filter segments. The edge of a multi-segment filter or a combination of filter segments is preferably arranged at the edge of the object to be observed when the multi-segment filter or the combination are observed from their photodetectors.
The photodetector preferably includes a linear camera, in particular CCD (charge coupled device) lines. Linear cameras or CCD lines are known per se. Reference is hereby made by way of example to DE 36 28 088 C2 in which corresponding CCDs are described. A linear camera preferably includes at least one CCD.
If the second line is spatially apart from the first line, not only can reflected radiation be measured, but transmitted rays or radiation, i.e., rays that pass from the illuminated line (first line) to the observed line (second line) through the material of the filter segments. Through this filter segments that are essentially the same in terms of color or brightness, but made of different material, can be discerned very well, since the transmission coefficients of electromagnetic radiation are different with different materials.
If two first lines are provided, such that one of the two first lines lies on the second line, a mixture of reflected and transmitted radiation can be recorded. If two second lines are provided, such that one of the two second lines lies on the first line, a very precise measurement of the properties of the multi-segment filters or the combination of filter segments is possible.
According to the invention, a machine of the tobacco-processing industry includes a device according to the invention described above.
Moreover, the invention is directed to a method for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry that includes:
A very precise measurement and thus a very good quality control of the multi-segment filters or combination of filter segments is possible through the method according to the invention.
The precision of the measurement is increased if the extension of the first line transversely to the longitudinal axis of the multi-segment filter or the combination of filter segments is less than half, in particular less than a quarter, in particular less than an eighth of the diameter of the multi-segment filter or the combination of filter segments.
The invention is directed to a method for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry that includes:
Preferably the second line is less than half, in particular less than a quarter, in particular less than an eighth of the diameter of the multi-segment filter or the combination of filter segments.
If the second line is arranged at the edge of the multi-segment filter or the combination of filter segments, in particular on the surface thereof, specific defects in the combination of filter segments or defects in the multi-segment filter can be detected very precisely, which defects could not have been detected or only poorly detected with an arrangement of the second line essentially in the center of the multi-segment filter or the combination of filter segments. The second line is preferably spatially apart from the first line. The second line preferably lies on the first line. Two first lines are preferably provided, whereby one of the two first lines lies on the second line. Two second lines are preferably provided, whereby one of the two second lines lies on the first line.
The present invention is directed to a device for measuring properties of combination of filter segments of the tobacco-processing industry. The device includes an illumination device structured and arranged to essentially uniformly illuminate, in a longitudinally axial manner, at least one section of the combination of filter segments, and a photodetector. The illumination device images a first line of electromagnetic radiation on the combination of filter segments having an extension transverse to the longitudinal axis of the combination of filter segments smaller than a diameter of the combination of filter segments.
In accordance with a feature of the invention, the combination of filter segments can include multi-segment filters.
According to another feature of the present invention, the extension of the first line transverse to the longitudinal axis of the combination of filter segments may be less than half the diameter of the combination of filter segments. Further, the extension of the first line can be less than one quarter of the diameter of the combination of filter segments. Still further, the extension of the first line may be less than one eighth of the diameter of the combination of filter segments.
According to the instant invention, the illumination device may include a linear laser.
The photodetector can include an optical system that images a second line in a longitudinally axial manner on the combination of filter segments. The second line may be arranged at an edge of the combination of filter segments.
According to a still further feature of the invention, the photodetector can include a linear camera. Moreover, the photodetector may include a charged coupled device line.
The second line can be spatially apart from the first line. The illumination device may further image another first line, such that the another first line on the second line. Further, the photodetector may further image another second line, such that the another second line lies on the first line.
The present invention is directed to a method for measuring properties of combinations of filter segments of the tobacco-processing industry. The method includes illuminating the combination of filter segments with a first line of electromagnetic radiation, recording the electromagnetic radiation at least one of reflected and scattered by the combination of filter segments, and comparing the recorded radiation with predetermined, desired values, and when a deviation beyond a predetermined tolerance range is detected, the combination of filter segments are deemed defective. An extension of the first line transversely to the longitudinal axis of the combination of filter segments is smaller than a diameter of the combination of filter segments.
According to a feature of the instant invention, the combination of filter segments may include multi-segment filters.
The extension of the first line transversely to the longitudinal axis of the combination of filter segments may be less than half of the diameter of the combination of filters. Further, the extension of the first line can be less than one quarter of the diameter of the combination of filter segments. Moreover, the extension of the first line can be less than one eighth of the diameter of the combination of filter segments.
The recording of electromagnetic radiation may include imaging a second line in a longitudinally axial manner on the combination of filter segments by a recording device. The second line can be arranged at an edge of the combination of filter segments. Further, the second line can be spatially apart from the first line, or the second line may lie on the first line.
In accordance with still another feature of the present invention, another first line can be illuminated, such that one of the first line and the another first line lie on the second line. Moreover, another second line can be imaged, such that one of the second line and the another second line lie on the first line.
The invention is directed to a machine of the tobacco-processing industry with the above-described device.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.
The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:
a diagrammatically illustrates a filter segment arrangement with transposed filter components,
b diagrammatically illustrates a signal over a length of path along the filter segment combination from
a diagrammatically illustrates a filter segment combination with a detached filter segment,
b diagrammatically illustrates a length of path along the filter segment combination from
a diagrammatically illustrates a filter segment combination with a filter segment in an incorrect position,
b diagrammatically illustrates a length of path along the filter segment combination from
a diagrammatically illustrates a part of a multi-segment filter with a gap between two filter segments,
b diagrammatically illustrates a length of path along the multi-segment filter from
a diagrammatically illustrates a filter segment combination with a tilted filter segment,
b diagrammatically illustrates a signal over a length of path along the filter segment combination from
c diagrammatically illustrates a signal over a length of path along the filter segment combination from
The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
New filter materials are increasingly being used in the cigarette industry. One particular focus is the use of so-called multi-segment filters. These are filters that are assembled from different filter materials. Manufacturing defects can occur in the production of these filters. The correspondingly defective products should not be processed further in the process. Some defects in particular are mentioned below with reference to
The interfaces between the filter segments 11 through 11″ are correspondingly drawn by lines indicated from
a shows a diagrammatic representation of a filter segment combination 10 in which there is a missing filter segment 31. It has been assumed in this case that a filter segment should have been arranged in place of the missing filter segment 31, which reflects a little less than the filter segments 11 and 11″, which could be, e.g., of the same material. For this reason the desired curve shown by a dashed line in
Another defect is indicated in
a shows a part of a multi-segment filter 10′ in a diagrammatic representation in which two filter segments 11 and 11′ are not adjacent as desired, but show too large a gap 15 between them. With materials of the filter segments 11 and 11′, for example, with the same reflection or the same transmission, the associated desired curve 12 shows at this joint an essentially straight line, which is also shown by a dashed line as is usual for desired curves 12 in this application. The signal curve 13 deviates clearly therefrom, so that the result of the measurement is a defective multi-segment filter 10′.
b again shows a filter segment combination 10 in diagrammatic representation in which the filter segment 11′ is tilted by 90° with respect to the longitudinal axis 30. The longitudinal axis of the tilted filter segment 11′ is tilted by 90° with respect to the longitudinal axis of the filter segments 11 and 11″ or the longitudinal axis of the filter segment combination 10. Two observation lines 16 and 17 that are spaced apart from one another are indicated diagrammatically in
The inventive concept on which this application is based is that a line on the filter components or on a multi-segment filter 10′ or in a filter segment combination 10 is imaged with the aid of an imaging optical system on the photosensitive layer of a linear array of a linear camera. Light/dark differences or color differences will lead accordingly to light/dark intensities or color intensities on the lines of the linear arrays. In a very simple embodiment, e.g., with a reflection measurement, the surface of the filter components is illuminated with a normal lamp or an array of diodes and the measurement is conducted in reflection, whereby the measuring device 25 has an optical system that makes it possible to observe such a line that has an extension transverse to the longitudinal axis of the object to be measured which is smaller than the diameter of the object to be measured.
In this manner, for example, transposed filter components can be recognized by the fact that the actual intensity path on the line of the camera chip runs differently than expected. See
Since filter components with an essentially white surface are increasingly being used, the actual contrasts are often much slighter than was indicated in the Figures. To boost the signal and in particular to detect gaps and to detect white/white transition points, filter techniques are used, e.g., the FIR filter technique (Finite Impulse Response), thus in particular digital filters with limited pulse response and with discrete time steps. Other filters or noise reduction devices can also be used.
The illumination is effected, e.g., with a laser light line 18 or laser beam line 18 that irradiates the surface of the filter components or the surface of the multi-segment filters. A laser micro line generator 13 LRM or 55 CM from Schäfter & Kirchhoff, for example, is suitable for this. The advantage of this type of illumination is that the light can be applied in a very concentrated manner in the circumferential direction of the filter components. It is thus possible to discern contrasts that would not be discernable with a more areal illumination. This is particularly advantageous if two scans or observation lines are provided close together, such as is indicated, e.g., in
Illumination with a laser beam line 18 is also advantageous if an observation line 16 is used that is spaced apart from the laser beam line 18, as diagrammatically indicated in
An improvement in contrast can be achieved if measurement is no longer made in direct reflection but in transmission, as is indicated in
A very simple arrangement of a corresponding device for measuring properties of multi-segment filters or combinations of filter segments of the tobacco-processing industry can be provided such that an essentially straight beam path is taken. The beam course of light sources and camera are hereby essentially straight in their optical axes.
A laser light source from Schäfter & Kirchhoff is also preferably used and a linear camera from Dalsa. The angles between the laser light source can be selected such that measurement can be made in reflection and/or in transmission.
In another embodiment or measuring device according to the invention two light sources, namely also in this case laser light sources 20, 20′, will image or illuminate the laser beam lines 18 and 18′ on filter segment combinations 10 that are spaced apart from one another. To this end the laser beams 23 and 23′ are deflected with mirrors 29 and 29′.
The filter segment combinations 10 move along the direction of movement 26, e.g., on a drum, which is not shown. Moreover, the longitudinal axis 30 of a filter segment combination 10 is shown and the diameter D.
The measuring device 25 furthermore comprises a linear camera 21 that records the light of the observation line 16 imaged through the optical system 22 and the mirror 28. The recorded light 24 is concentrated accordingly by the lens 22. On the light-sensitive element, e.g., a CCD line, which is not shown, of the linear camera 21, light reflected from the laser beam 23 in the laser beam line 18′ is guided to the line camera 21 and light transmitted from the laser beam 23 on the laser beam line 18 to the observation line 16 through the filter segment combination 10 is imaged in the linear camera 21.
It could now additionally be provided to use another linear camera 21 in order to also image an observation line 17, not shown, in the other linear camera, not shown, whereby the observation line 17 is spaced apart from the observation line 16 and can also be arranged spaced apart from the laser beam line 18 in order to improve the contrast for the transmission measurement. The other observation line 17 could also coincide with the laser beam line 18. It can also be provided to switch on the two light sources alternately or to alternately block out laser beams 23 and 23′ in order in this manner to prevent a mutual interference with the reflection measurement and the transmission measurement.
This can occur in a cycle in which a single filter segment combination 10 is located in corresponding measuring positions.
The recording of measured values preferably occurs with contact image sensors.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2005 046 581.1 | Sep 2005 | DE | national |
