EP1036003A1

EP1036003A1 - Method for checking that batches of cigarettes are complete and that the cigarettes are sufficiently filled

Info

Publication number: EP1036003A1
Application number: EP98963471A
Authority: EP
Inventors: Heinz Focke; Michael Czarnotta
Original assignee: Focke and Co GmbH and Co KG
Current assignee: Focke and Co GmbH and Co KG
Priority date: 1997-12-02
Filing date: 1998-11-17
Publication date: 2000-09-20
Anticipated expiration: 2018-11-17
Also published as: JP2001524425A; CN1280541A; CN1105061C; EP1036003B1; BR9814714B1; DE19753333A1; US6531693B1; WO1999028190A1; DE59810930D1; ES2216342T3; BR9814714A

Abstract

The invention relates to a method for checking that batches of cigarettes are complete and that the cigarettes are sufficiently filled. In spite of careful manufacturing, when cigarettes are produced and batches of cigarettes are filled in cigarette packs (11) using high-performance machines, it is possible that some of the packs of cigarettes manufactured have cigarettes missing or contain cigarettes which are not sufficiently filled with tobacco. The invention provides an improved, non-contact method of checking the batches of cigarettes or the individual cigarettes. According to this method, the intensity signal of a CCD camera or a CCD-line-scanning chip in subareas of the front ends (24) of the cigarettes and/or the spaces between them is measured and analysed in the front end area of the batch of cigarettes. The inventive method therefore provides a means of checking that batches of cigarettes are complete and that the cigarettes are sufficiently filled in high-performance machines such as pocket conveyors or revolving folders.

Description

Procedure for checking the completeness of cigarette groups and the filling of the cigarettes

description

The invention relates to a method for checking ordered cigarette groups corresponding to the content of a cigarette pack with an electro-optical test device connected to a signal data processing device, preferably a CCD line chip or a CCD camera, for measuring the intensity of through the filter-side end faces of the cigarettes reflected light. Furthermore, the invention relates to a method for checking ordered cigarette groups corresponding to the content of a cigarette pack with an electro-optical test device, preferably a CCD camera, connected to a signal data processing, for measuring the intensity of reflected light, a measuring field preferably formed from pixels of the test device is assigned to at least one partial area of the end faces of the cigarettes.

High-performance machines are required for the production of cigarettes and the filling of cigarette groups in cigarette packs. Despite careful manufacturing, however, it often happens that the cigarette packs created and delivered to the customer contain missing cigarettes or cigarettes insufficiently filled with tobacco. When selecting test methods for sorting out such faulty cigarette groups, it should be noted that the test must take place in the rapid, continuous or discontinuous conveying process.

In a previously used test method, an ordered cigarette group corresponding to the content of a cigarette pack is moved past a test device, in which the intensities of reflected light measured by a CCD camera are statistically evaluated. The object of the invention is to propose an improved, contactless test method for checking the completeness of cigarette groups and / or the filling of the cigarettes with tobacco.

To achieve this object, the method according to the invention is characterized in that a measuring field formed by the test device, preferably by the pixels of the CCD line chip or the CCD camera, is assigned to the end faces of the cigarettes and the cigarette spaces formed between them, at least partial areas of the measuring field, in particular pixels of the CCD camera or the CCD line chip are arranged in curved or rectilinear, in particular horizontal or vertical, evaluation bars and the measurement signal measured along the evaluation bar is evaluated to check the completeness of the cigarette group in the signal data processing.

The measuring device for checking the cigarette groups thus works contactlessly on the basis of a CCD line chip or a CCD camera, so that the cigarette group can also be checked with a rapid conveying cycle. Here, the measuring element can be arranged at any point in the conveying process, as long as the end faces of the cigarette groups are freely accessible in it. For example, the check can be carried out in a pocket conveyor during the conveyance. Another option is to check the cigarette groups in a folding turret.

According to the invention, the method is characterized in a further embodiment with regard to the evaluation of the intensity curve supplied by the CCD camera or the CCD line chip, in that from a count of the passes of the intensity curve by a threshold value with subsequent exceeding and / or falling below the threshold value the number of cigarettes in the area of the evaluation bank (s) is determined. This evaluation method is based on the fact that the reflected light is larger in the area of the bright filter surfaces of the cigarettes is the intensity measured in the area of the dark cigarette spaces formed by neighboring cigarettes. An increase in the measured intensity curve can therefore be evaluated as a transition from a cigarette space to a filter-side end of a cigarette. In the absence of a cigarette in a row of cigarettes, the high intensity in the area of the filter surfaces is achieved less than that of a complete cigarette row. This is detected on the basis of the counting of the passes of the intensity curve through a threshold value.

In the absence of a cigarette within a cigarette group with several rows of cigarettes, neighboring cigarettes shift. This has the consequence that the distance between the first and last cigarette of a row of cigarettes is reduced due to the absence of a cigarette. A further method according to the invention is therefore characterized in that the completeness of the cigarette group is determined from the comparison of the distance between the first and last pass of the intensity curve by means of a threshold value with a target value.

The number of high-sided measured faces of the cigarettes in the area of the evaluation bar of the CCD line chip or the CCD camera increases the number of high measured intensity values. Accordingly, in a further method according to the invention, the area below the curve of the measured intensity signal measured, in particular by summing up the intensity values measured along the evaluation bar, can be compared with a target value determined for the complete cigarette group.

To achieve the object, a further method according to the invention is characterized in that a measurement signal measured in the pixels assigned to the end faces of the cigarettes and the cigarette spaces between them is evaluated as a two-dimensional measurement field in accordance with the horizontal and vertical positions of the pixels. In a three-dimensional representation of the measured intensity over the horizontal and vertical position of the pixels in the two-dimensional measuring field, the intensity curve can thus be represented as a curved surface that has high plateaus in the area of light cigarette surfaces, for example in the area of the light end faces of cigarettes, and valleys for the Areas with low measurement intensities, for example in the area of the cigarette rooms.

In a method according to the invention, this relief-like change of mountains with high plateaus and valleys is evaluated in such a way that with a tobacco-side arrangement of the measuring field, the presence of a large number of small adjacent intensity values is used as an indicator for recesses in the filling of the cigarettes with tobacco. In this test method, therefore, a specific search is made for valleys, i.e. flat areas with small neighboring intensity values. In the area of a valley there is therefore a flat shadow area on the tobacco side of the cigarette. This can be used as an indicator for recesses in the filling of the cigarettes, so-called blowholes.

In the absence of a cigarette from a group of cigarettes and when the cigarettes are examined in the area of the end faces of the cigarettes, the absence of a cigarette in the group of cigarettes leads to the fact that in the area where a plateau of high intensity should be present for a complete group of cigarettes, there is a "valley" with low measurement intensities. In the area of the Sol 1 positions of the end filter surfaces, a large number of low measurement intensities are measured instead of many adjacent high measurement intensities. When determining the frequency distribution of the measured values with measurement intensities within predefined intensity classes, the occurrence of a high frequency with high measurement intensities indicates the presence of a bright filter surface, while the presence of large frequencies with small measurement intensities can be evaluated as an indicator of a dark space between cigarettes.

Further methods relate to preferred configurations of the invention.

Further details of the method are explained in more detail below with reference to the exemplary embodiments shown in the drawings. It shows:

1 conveyor device for soft cup packs in side view,

2 test device for testing cigarette groups in plan view,

3 defective cigarette group in the pocket of a pocket conveyor,

4 horizontal and vertical evaluation bar for checking a cigarette group,

5 shows an example of a measured intensity signal along a horizontal evaluation bar,

6 shows an example of a measured intensity signal along a vertical evaluation bar,

7 measuring ranges of the test method in the filter area and in the area of the cigarette spaces,

8 frequency distribution of measured intensities in the filter region,

9 frequency distribution of measured intensities in the area of the cigarette spaces, Fig. 10 measurement results of the CCD camera, as measured on the ^{"tobacco-side} end face in the area of a correctly-filled cigarette group,

11 measurement result of the CCD camera, measured on the tobacco-side front side in the area of an incorrectly filled cigarette group,

12 three-dimensional representation of the intensity difference 1,

13 block diagram of the measurement control and signal data processing for checking the completeness and filling of the cigarette group.

The details shown in the drawings relate to a preferred application example, namely the manufacture of cigarette packs of the soft cup pack type. 1 shows the basic concept of a packaging machine 10 for the production of such cigarette packs 11. The cigarettes are transferred to the packaging machine 10 in the area of a cigarette magazine 12. This is an organ customary in packaging machines 10 for cigarettes for storing cigarettes and for dispensing cigarette groups 13 corresponding to the contents of a cigarette pack 11. For this purpose, the cigarette magazine 12 is provided in the lower area with magazine chutes 14 which act as shaft groups are summarized. A cigarette group 13 is pushed out of each shaft group by sliders and inserted into pockets 15 of a pocket chain 16, specifically in the area of a lower conveyor run 17.

The pocket chain 16 transports the cigarette groups 13 to a folding turret 18, to which they are transferred by pushing out the pockets 15 of the pocket chain 16. Details of the structure of the cigarette magazine 12, the pocket chain 16 and the folding turret 18 can be found in EP 226 872. At the position marked with the arrows A or B in the conveying flow, namely in the area of the lower conveying run 17 or in the folding turret 18, the cigarette groups 13 are checked for completeness or completeness of the filling of the cigarettes by the test method according to the invention. Downstream of the test device 19 in the conveying direction is an ejector 20, which is actuated in the event of an error signal from the test device 19 to separate out defective cigarette groups 13.

The test device has a test device 20, preferably a CCD line chip or a CCD camera. An optical system 22 is arranged upstream of the test element 21. Another component of the test device are, for example, two light sources 23, which are preferably inclined at an angle of 5 to 15 ° with respect to the recording direction of the test device 21. Test organ 21 and associated light sources 23 are aligned such that the light from light sources 23 reflected by an end face 24 of cigarette pack 11 is detected by test organ 21. The light source 23, preferably a light source of high intensity or a laser, can be controlled stroboscopically in time with the machine. In the embodiment shown in Fig. 2, a test device 19 is arranged on the fi 1 terseit term face 24 of the cigarette packs 11. Here, for example, the cigarette group is checked for completeness. Another test device is arranged on the tobacco-side end face 24 of a cigarette group 13. With this, for example, the complete filling of individual cigarettes 25 can be checked, but it is also possible here to simultaneously check the completeness of the cigarette group 13 and the filling of the cigarettes 25 with tobacco.

Fig. 3 shows the fil tersei term face 24 of a cigarette group 13 and one of the cigarette group 13 associated pocket 15 of the pocket chain 16. On the pocket 16, a vertical marker 26 and a horizontal marker 27 for aligning the image of the test device 21 are provided. With a vertical kalen displacement of the pocket 15, the horizontal marker 27 is vertically displaced, with a slight time delay in the recording of an intensity curve 28 by the test organ 21, i.e. the CCD camera or the CCD line chip, the vertical marker 26 is laterally in the image taken from it Target position shifted. The image captured by the CCD camera is aligned using the markings in the coordinate system of the evaluation unit.

A complete cigarette group 13 has, for example, seven cigarettes 25 in each outer, horizontal row of cigarettes 29, the inner horizontal row of cigarettes 30 contains six cigarettes. The cigarette group 13 shown is thus a missing group. As a result of a missing cigarette in the inner row of cigarettes 30, two cigarettes 31 and 32 of the outer rows of cigarettes 29 are shifted from their sol 1 positions into the interior of the pocket 15. Such fault groups are separated using the following measuring ranges:

the dot-dash circles 33 mark the desired positions of the cigarettes in the cigarette group,

- The circular areas with solid border 34 are partial areas of the cigarette front, their importance for the

Evaluation method is shown below,

- Further evaluation areas are the shadow areas 35 marked with black circular areas in the area of the cigarette spaces 36,

- In Fig. 4, horizontal evaluation bars 37 are marked with horizontal lines, which preferably run such that an evaluation bar both the area of the target position of each cigarette 33 of a row of cigarettes 29 or 30 and a shadow area 35 in the area of two adjacent cigarettes of a row of cigarettes 29 or 30 goes through, - Vertical evaluation bars 38 are preferably arranged such that the cigarette spaces 36 between cigarettes of adjacent rows of cigarettes are passed through in the vertical direction.

The circular surfaces 34 and shadow regions 35 can of course also have a contour that deviates from the circular shape shown.

In order to determine the completeness of a row of cigarettes 29, 30, the light intensity reflected along a horizontal evaluation bar 37 is measured with a test organ 21 in an evaluation method according to the invention. For this purpose, the evaluation bar 37 is imaged by several pixels of the CCD line chip or the CCD camera. Each pixel detects the light intensity of a section of the evaluation bar 37. In FIG. 5, the horizontal evaluation bar 37 is divided into 230 sections of the same size by 230 pixels. The measurement signal 39 shown represents the measured intensity for the pixels 0 to 229. The light intensity is usually specified in the unit candela. The intensity at the measuring location is converted by the CCD camera into a proportional measuring signal, for example into a voltage. For this reason, the measured values for the intensities are given below without units. The absolute values of the measured values are marked with square brackets in the following text.

The intensity of the reflected light is high in the area of the pixels assigned to the (bright) end faces 24 or filters of the cigarettes, see here the plateaus 40 of high intensity in FIG. 5. The area breaks in the area of the pixels assigned to the shadow areas 35 between the cigarettes 25 Intensity. The dashed line here shows the measured error signal 41 for the case of a missing cigarette. The method for evaluating the measurement signal 39 can, for example, count the passages 42 of the measurement signal through a threshold value 43. In the example shown, the measurement signal 39 passes through the threshold value 43 seven times in the positive or negative direction. There are therefore seven cigarettes in the row of cigarettes 29, 30.

Another method determines the area under the measurement signal 39 shown in FIG. 5. This can be determined by adding up the intensities measured by pixels 0 to 229. The deviation of a sum determined in this way from a desired value can be used as an indicator of the absence of a cigarette 25 in the row of cigarettes 29, 30, since in the area of the error signal 41 marked with a dash-dotted line, the defect area 44 under the curve is due to the missing cigarette 25 is very much smaller than the comparison surface 45, so only small values are included in the summation.

In a further evaluation method, the intensity measured by the vertical evaluation bars 38 is evaluated, see FIG. 6. The vertical evaluation bars 38 pass through the cigarette end faces preferably in the immediate vicinity of the end face center 46. The two plateaus 47 of high intensity in FIG. 6 of the measurement signal 39 shown here characterize measurements in the area of an end face 24. Between the two plateaus 47, the edge area 48 of a cigarette 25 of the inner row of cigarettes 30 is passed through, so that here the intensity increases over a smaller width and forms a local maximum 49. According to the previously described method, the exceeding or falling below a threshold 1 value 43 can also be used for the evaluation. In a simplification of this method, however, only the first passage 50 of the measurement signal 39 through the threshold value 43 and the last passage 51 of the measurement signal 39 through the threshold value 43 are evaluated. The distances D1 and D2 can be determined from the pixel assigned to this first pass 50 or last pass 51. Alternatively the first pass can of course also be determined from both sides or from above and from below (for the direction of measurement see also the arrows in FIG. 4).

The lack of a cigarette 25 in the cigarette group 13 has the consequence that the distance between adjacent cigarettes 25 from the side wall 52 of the pocket 15 is increased, see here cigarettes 31 and 32 in FIG. 3. This has an increase in the distances D1 and D2 Episode. An error signal can be determined by comparing the sum D1 + D2 with a setpoint. Analogously to this, the distance D between the first pass 50 and the last pass 51 can of course also be used for the evaluation.

The use of the test method described can cause problems when testing the cigarette group 13 in the area of the folding turret 18. In the folding turret, the cigarette groups 13 are not surrounded by dark pockets 15, but by light packaging material. As a result, the measurement signal 39 may have high intensities outside the cigarette group 13 and for this reason there is no first and last passage 50, 51. In this case, a further method for determining the completeness of the cigarette group 13 can be used, which is based on the intensities measured in the partial area, namely the circular area 34 of the end face 24 and the shadow areas 35. In the circular areas 24 of the fil tersei term face of a cigarette, several pixels are arranged here. The bright, filter-side end faces 24 reflect light with a high intensity, for example intensities between [59] and [63], see. Fig. 8. For the evaluation of the intensities measured in the partial areas assigned to the end face 24, several classes 54 of the intensity are formed, for example classes 54 with intensity values in the range from [59] - [60], [60] - [61] and [61] - [62]. 8 shows the frequency N of the pixels per intensity class for a measurement in the area of the filter-side end face 24, the frequency 72 is applied over the intensity class 71. An intensity> [60] has been measured for more than 238 pixels. The number of pixels with intensities below a threshold 1 value is approximately zero here if the face 1 24 of the cigarette 25 is in the desired position (in practice, the intensity below a threshold 1 value is approximately due to measurement inaccuracies) Zero).

In the absence of a cigarette 25 of the cigarette group 13, the remaining cigarettes 25 of the cigarette group 13 are shifted. This has the consequence that shadow areas 35 move into the light filter-like So! 1 Move the positions of the cigarettes 33. If there are measured values with intensities below the threshold 1 value 55, this can be evaluated as an indicator of an incorrect position of one or more cigarettes 25. In the case of digitized intensity values, the classes can also be formed from the digitization stages, so that pixels of the same intensity are then added up.

For measurements in the shadow area 35 in the cigarette space 36 between adjacent cigarettes 25, the intensity of the reflected light is very small, see FIG. 9. The number of pixels is smaller here because the assigned measuring areas for the shadow areas 35 are smaller. The number of pixels with intensities greater than a predefined threshold value 56 is zero for a partial area of the measuring field which lies in the target area of the shadow areas 35. The displacement of the remaining cigarettes 25 from their desired position 33 due to the absence of a cigarette 25 from the cigarette group 13 has the result that 35 light filter surfaces are arranged in the desired positions 33 of the shadow areas. Thus, if measurements with intensities above a threshold value 56 are available for measurements in the shadow region 35, this can be evaluated as an indicator of the incorrect position of one or more cigarettes 25.

In a further measuring method, a measuring surface 57 in the area of the tobacco-side end face 24 of the cigarette group 13 divided into several pixel areas 58, each of which is assigned a pixel of the CCD camera. 10 shows an enlargement of a section of the measuring area 57, in which each square describes the pixel area 58 captured by a pixel and the numerical value assigned to this square describes the brightness measured in the pixel area 58. Dark pixel areas 58 identify areas with low intensities, that is, dark end face areas, bright pixel areas 60 identify bright measurement areas.

The circular contours 61 formed by pixels with high measuring intensities correspond here to the outer contour of the cigarettes 25, since the light tobacco casing reflects light with high intensity. The intensity fluctuates very strongly within the casing at medium values. This is due to the fact that the end face 24 formed by the tobacco is uneven. Figure 10 shows the measurement result of correctly formed cigarettes 25. In the area of the front face 24 of the cigarette 25 formed by the tobacco, the intensity fluctuates very strongly, but there are no large areas of low intensity formed by several adjacent pixel areas 58. If the cigarettes are not properly filled with tobacco, there may be recesses in the end face of the cigarettes. These areas are formed by areas of low pixel intensity formed from several pixel areas 58, cf. see picture 11. Counting the number of neighboring pixel areas 58 with intensities below a predefined threshold 1 value can thus be used as an indicator of inadequately filled cigarettes 25.

12 shows a section of the result of the intensity measurement by means of the test device, for example a CCD camera, with an arrangement on the side of the filter. The intensity 75 is plotted here over the x-axis 73 and the y-axis, that is to say as a function of the horizontal and vertical measuring position. Here, the plateaus 61 can be seen with high intensities in the area of the light-colored end faces 24. Every plateau 62 is formed by the measured intensities of many pixels, here approximately 500. In the dark shadow areas ^"35 adjacent cigarettes 25 Valleys 63 are formed from in three-dimensional representation. For a properly formed Ziga- save group 13 are thus 7 + 6 + 7 = 20 such separated by valleys 63 plateaus 62 before, in the absence of a cigarette 25 a plateau 62 is replaced by an additional valley 63. The volume under such a measuring surface 64 is dependent on the number of plateaus 62. Accordingly, the deviation of the determined volume from a target value can be evaluated as an indicator of missing cigarettes 25. The determination of the The volume is proportional to the sum of the individual intensities measured in the measuring surface 64, so that the volume or a measure proportional to it can be determined in a simple manner. Of course, such an evaluation method can also be carried out on the tobacco-side end faces 24 of the cigarette group 13, so that here the examination of the compl RESISTANCE the cigarette group 13 and the filling of the cigarettes 25 may be carried out with a checker 21st

Of course, several of the test methods shown can also be used simultaneously to increase the safety of the test method.

The measuring methods shown have the following block diagram 65 in common for signal data processing and machine control, see FIG. Fig. 13:

The test process is started by a trigger signal 66, which is generated, for example, by a light barrier when a new bag 15 with cigarette group 13 arrives in the test area. This trigger signal 66 is fed to the image processing 67, which stroboscopically controls a light source 23, for example a laser. Simultaneously with the flashing of the cigarette group 13, an image is taken by means of the test device 21, for example a CCD line chip or a CCD camera, and fed to the image processing unit 67. This is fed to the machine control 69 via a suitable I / O interface 68. In addition to checking the completeness of the cigarette group 13 and the filling of the cigarettes 25 with tobacco, the signal processing 70 must also monitor whether the test organs 21 are ready for operation, the image of the test organ 21 is recorded at the correct time and / or the signal quality is sufficient. For example, in the case of poor lighting conditions as a result of a defective light source 23, an error signal must be generated so that the machine can be stopped and the light source 23 can be replaced. The machine control 69 is also connected to an ejector 71, so that when an incomplete cigarette group 13 is recognized or the cigarettes 25 are not completely filled, the ejector 71 can be actuated to remove the defective cigarette group 13. Of course, several separate test devices 19 can also be controlled and evaluated simultaneously or in succession.

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Reference numerals

10 packaging machine 58 pixel area

11 cigarette pack 59 dark pixel area

12 cigarette magazines 60 bright pixel areas

13 cigarette group 61 circular contour

14 magazine well 62 plateau

15 bag 63 valley

16 pocket chain 64 measurement curve

17 lower funding strand 65 block diagram

18 folding turret 66 trigger signal

19 Inspection device 67 Image processing 0 Ejector 68 I / 0 interface 1 Inspection device 69 Machine control 2 Optics 70 Signal data processing 3 Light source processing 4 Front side 71 Intensity class 5 Cigarette 72 Frequency 6 vertical marking 73 x-axis 7 horizontal marking 74 y-axis 8 Intensity curve 75 intensity 9 outer row of cigarettes 0 inner row of cigarettes 1 cigarette 2 cigarette 3 target position of the cigarette 4 circular area 5 shadow area 6 cigarette space 7 horizontal evaluation bar 8 vertical evaluation bar 9 measurement signal 0 plateau 1 error signal 2 pass 3 threshold value 4 error area 5 comparison area 6 end face center 7 plateau 8 edge area 9 local maximum 0 first pass 1 last pass 2 side wall 3 filter 4 class 5 threshold 6 threshold 7 measurement area

Claims

Expectations

1. A method for checking ordered, the content of a cigarette pack (11) corresponding cigarette groups (13) with a signal data processing (70) connected electro-optical test device (21), preferably a CCD line chip or a CCD camera, for measurement the intensity of light reflected by filter-side end faces (24) of the cigarettes (25), characterized in that

a) a measuring field formed by the test device (21), preferably by the pixels of the CCD line chip or the CCD camera, is assigned to the end faces (24) of the cigarettes (25) and the cigarette spaces (36) formed between them;

b) at least partial areas of the measuring field, in particular pixels of the CCD camera or the CCD line chip, are arranged in curved or rectilinear, in particular horizontal or vertical, evaluation bars (37, 38),

c) the measurement signal measured along the evaluation bar (37, 38) for checking the completeness of the cigarette group (13) is evaluated in the signal data processing (70).

2. The method according to claim 1, characterized in that from a count of the passages (42) of the measurement signal by one

Threshold value (43) with subsequent exceeding and / or falling below the threshold value (43), the number of cigarettes (25) in the region of the evaluation bank (s) (s) (37, 38) is determined.

3. The method according to claim 1, characterized in that the completeness of the cigarette group (13) is determined from the comparison of the distance D of the first and last pass of the intensity curve by a threshold value (43) with a target value.

4. The method according to claim 1, characterized in that the, in particular determined by summing the measured values along the evaluation bar (37, 38), area (44, 45) below the measurement signal (39) with one for the complete cigarette group (13) determined target value is compared.

5. Method for checking ordered cigarette groups (13) corresponding to the content of a cigarette packet (11) with an electro-optical test device (21) connected to signal data processing (70), preferably a CCD camera, for measuring the intensity of reflected light, wherein a measurement field, preferably formed from pixels of the test device, is assigned to at least one partial area of the end faces of the cigarettes, characterized in that a measurement signal (39) measured in the pixels assigned to the end faces (24) of the cigarettes (25) and the cigarette spaces (36) ) is evaluated as a two-dimensional measuring field in accordance with the horizontal and vertical positions of the pixels.

6. The method according to claim 5, characterized in that the presence of a large number of small adjacent intensity values is used as an indicator for recesses in the filling of the cigarettes (25) with tobacco in a tobacco-side arrangement of the measuring field.

7. The method according to claim 5, characterized in that with fil tersei term arrangement of the measuring field in the representation of the intensity above the horizontal and vertical position of the pixel associated with the measured value, the volume formed under the measurement curve (64) as an indicator of missing cigarettes (25th ) is used.

8. The method according to claim 5, characterized in that the number of pixels with measurement intensities for fil terseite arrangement of the measuring field to determine a frequency distribution Within predefined classes (54) the intensity is determined.

9. The method according to claim 8, characterized in that at the target positions of the sub-fields assigned to the cigarette spaces of the measuring field, the presence of too large or too small frequencies of measured values above or below a threshold 1 value (55) of the intensity as an indicator of an incomplete cigarette group (13) is evaluated.

10. The method according to claim 8, characterized in that on the So! 1 positions of the fi 1 ts end faces (24) of the subfields associated with the cigarettes (25) of the measuring field, the presence of large or small frequencies of measured values below or above a threshold value (55, 56) of the intensity is evaluated as an indicator of an incomplete cigarette group .

11. The method according to any one of the preceding claims, characterized in that if the volume of the cigarette groups (13) is constant, an error signal is generated which is fed to an ejector (71) arranged downstream of the testing device (19) in the conveying direction.

12. The method according to any one of the preceding claims, characterized in that the measured value recording and processing takes place in the machine cycle, for example triggered by the trigger signal (66) of a light barrier at the time of the entry of a cigarette group (13) in the test area.

13. The method according to any one of the preceding claims, characterized in that the measured value recording and processing by one or more measuring and evaluation devices takes place simultaneously for at least one cigarette groups (13).

14. The method according to any one of the preceding claims, characterized in that the measuring bar (37, 38) or the measuring field with With the help of markings (26, 27), preferably horizontal or vertical, arranged in the area or the vicinity of the cigarette groups (13).

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