EP3085253B1 - Rod processing machine in the tobacco-processing industry, and method for producing multi-segment rods - Google Patents

Description

The present invention relates to a rod making machine of the tobacco processing industry for manufacturing multi-segment bars, comprising an endless driven format strip for conveying a wrapping strip laid on the format strip and a series of segments laid on the wrapping strip, an enclosing means for enclosing the segments with the wrapping strip, and a optical measuring device for detecting a property of the formed from the segments and the wrapping strip multi-segment strand. The present invention further relates to a method of manufacturing multi-segment bars of the tobacco processing industry.
A stranding machine of the tobacco processing industry for producing multi-segment bars with an endless format belt and an enclosure device has long been known, see for example DE 27 36 871 A1 ,
It is also already known to provide an optical measuring device for detecting the individual segments in such a stranding machine, see, for example EP 1 913 824 A1 , The signal from such an optical measuring device is used, for example, for the cutting position control of a subsequent cutting device for cutting the endless strand into individual bars. document EP 2 628 399 A1 discloses a stranding machine for multi-segment rods, comprising an endless driven format belt for conveying a wrapping strip and a series of segments placed on the wrapping strip, wrapping means for enclosing the segments with the wrapping strip, and an optical measuring device for detecting a property of the Segementen and the wrapping strip formed multi-segment strand. Increasingly, opaque encasing materials are used in the tobacco processing industry, where currently known optical measuring devices do not permit position detection of the segments in the closed loop. The use of non-optical measuring devices, such as microwave or X-ray measuring devices, however, is relatively complicated and expensive, and also requires a considerable amount of space. In addition, the latter are relatively slow in terms of the required evaluation speed, so that they are not suitable for online measurement for online applications.
The object of the invention is to provide a stranding machine and a method in which a reliable optical detection of the segments is possible regardless of the nature of the wrapping material.

The invention solves this problem with the features of the independent claims. The arrangement of the light exit in the conveying direction before the enclosure means an inspection of the segments before their wrapping with the wrapping strip on the still open strand is possible. For a stranding machine with a format band, it is surprising that such an arrangement is possible, since in the area before the wrapping of the segments only very little space is available and the field of view is usually covered by a hold-down for holding down the segments on the format ,

Conventional optical sensors with corresponding optical elements can only partially reach all inspection points. Especially with position markings on a wrapping material strip, such as printing marks, and the mechanical boundary conditions in the format area, the angle of incidence is too shallow, i.e., too small. too little light passes from the object back to the receiving optics of the conventional sensor. A mechanical hold-down and the guidance of the still loose segments complicate the integration of conventional sensors.

Preferably, the light exit is formed by at least one light guide. By means of optical fibers, for example based on glass fiber, the optical detection can be realized advantageously with minimal installation space. Due to the small design, a measuring distance and angle of incidence can be realized, which enables a reliable measurement without additional optical elements.

The at least one light exit is preferably arranged in direct measuring relationship to the surface to be measured. Within the scope of this application, direct measurement relationship means that the light emerging from the light exit falls directly onto the object to be examined (segment or wrapping strip) without optical elements arranged therebetween in the beam path, such as lenses, filters or the like.

Preferably, the measuring device is configured to carry out at least one punctiform and / or rectangular reflection measurement. Optical reflection measurements can be carried out with comparatively little effort, in comparison to optical transmission measurements, which do not always work reliably depending on the material investigated. A point measurement means that only the light intensity reflected by a point or light spot is determined, but a two-dimensional image consisting of a multiplicity of pixels does not have to be elaborately taken and evaluated, for example by means of a camera.

Preferably, the measuring device comprises a first light exit, which is arranged in measuring relation to the segment strand. In this way, it is possible to determine advantageously (axial) positions of the individual segments along the conveying direction and / or lengths of the segments, in particular of different segments of different nature. The segments differ advantageously for this purpose in the color scheme.

Preferably, the measuring device comprises a second light exit, which is arranged in measuring relation to the wrapping strip. This advantageously makes it possible to detect optical differentiations of markings or printed marks on the wrapping strip, in particular on the inside of the wrapping strip, from which the position of the wrapping strip relative to the segments can advantageously be determined. The markers or print marks differ advantageously for this purpose from the color of the wrapper strip.

Preferably, the light exits are arranged at an angle in the range between 0 ° and 180 °, more preferably between 50 ° and 110 ° to each other. This advantageously enables a reliable detection of both the segments as well as marks or print marks on the wrapping paper with sufficiently steep angles of incidence of light.

Preferably, each light emission is generated by an associated transmitting optical fiber, wherein in particular each transmitting optical fiber, a corresponding receiving optical fiber can be assigned. In a preferred embodiment, the at least one light guide is advantageously held in a light guide head. In this case, the transmitting optical waveguide and the corresponding receiving optical waveguide are preferably arranged in a common outlet opening of the optical waveguide head. With such an embodiment, the optical detection can be realized with the desired functionality in a small space.

In an advantageous embodiment, the light guide head is attached to a hold-down for holding down the segments. Since the hold-down is in a fixed spatial relationship to the segments, this is achieved in a simple manner that also the light guide head is in a fixed spatial relationship to the multi-segment strand. This is advantageous for a reliable and accurate optical measurement.

The optical fiber head can be attached directly or indirectly, for example via a support element, to the hold-down device. In one embodiment, the light guide head is guided through an opening in the hold-down, which can be particularly space-saving. Preferably For example, the tubular or pin-shaped optical fiber head at an angle in the range between 0 ° and 90 °, more preferably between 30 ° and 60 ° inclined to the horizontal. This advantageously allows both a detection of the segments and the wrapping strip by means of a simply constructed optical fiber head.

The invention is applicable to all extrusion machines of the tobacco processing industry for the manufacture of multi-segment bars. An advantageous application relates to a stranding machine for producing multi-segment filter rods. The invention can be used, in particular, for quality assurance with regard to defined lengths of the segments and / or possible cutting position monitoring or control. A relative position detection can be advantageously realized by a corresponding light guide arrangement, for example with contrast or color sensors.

Fig. 1

eine schematische Seitenansicht einer Multisegment-Filterstabherstellmaschine;

Fig. 2

eine perspektivische Ansicht auf den Formatbereich einer Multisegment-Filterstabherstellmaschine;

Fig. 3

ein vergrößerter Auszug aus Figur 2 unter Weglassung des Niederhalters;

Fig. 4

eine perspektivische Schnittdarstellung des Niederhalters mit integriertem Lichtleiterkopf; und

Fig. 5

eine Schnittdarstellung des Lichtleiterkopfs mit zwei Lichtaustritten unter Weglassung des Niederhalters.

The invention will be explained below with reference to preferred embodiments with reference to the accompanying figures. It shows

Fig. 1

a schematic side view of a multi-segment filter rod manufacturing machine;

Fig. 2

a perspective view of the format area of a multi-segment filter rod manufacturing machine;

Fig. 3

an enlarged excerpt FIG. 2 omitting the hold-down;

Fig. 4

a perspective sectional view of the hold-down with integrated light guide head; and

Fig. 5

a sectional view of the light guide head with two light leaks, omitting the blank holder.

The stranding machine 10 is part of a machine for producing multi-segment filter rods 48, each consisting of a plurality of optically distinguishable filter rod segments 17. In one of the strand machine 10 upstream, not shown in detail group forming device 12 groups of filter segments 17 are assembled and placed longitudinally by means of a loading device 33 on a withdrawn from a reel 37 and provided with a gluing device 38 with glue envelope strip 39. In this way, an initially open multisegment filter strand 41 is formed from the longitudinally juxtaposed filter segment groups. On the Inside the wrapper strip 39, optically detectable markings or print marks 30 can be arranged. In particular, the wrapping strip 39 may be a wrapping paper strip.

The wrapping strip 39 and the multi-segment filter strand 41 rest on a strand conveyor in the form of an endless format strip 42 driven by a drive 40. The format belt 42 guides the components 39, 41 through a format 45, or enclosing device 43, which completely wraps the wrapping strip 39 around the filter strand 41, due to the sizing, thus forming an endless closed multi-segment filter strand 44. This can pass through a seam plate 46, in which the adhesive seam is dried by means of heat input or cooling. Subsequently, individual multi-segment filter rods 48 are continuously cut off from the multi-segment filter strand 44 by means of a cutting device 47 and transferred to a downstream delivery conveyor.

In the FIGS. 2 and 3 the stranding machine 10 is shown in a cross section in the region between the loading device 33 and the enclosing device 43, in which the filter strand 41 is not yet enclosed by the wrapping paper. In this area, the format 45 has a longitudinal axial recess 49 for receiving and guiding the filter strand 41. In the recess 49, the format tape 45 is placed in a U-shaped cross section on the format 45. In turn, the wrapping strip 39 is placed on the format strip 45 in a U-shaped cross-section, wherein the legs 39a of the wrapping strip 39 project upwards beyond the filter strand 41.

As a suction of the filter strand 41 to the format 45 is not practicable due to the format strip 42, a longitudinally axially extending hold-down 20 is provided in the Figures 2 and 4 is shown. The plate-shaped or strip-shaped holding-down device 20, for example, is arranged on the format 45 or in the recess 49 of the format 45 for holding down the segments 17 forming the filter strand 41. The hold-down 20 may be pivotable about a horizontal axis to make the format 45 accessible in case of failure.

In the region between the insertion device 33 and the enclosing device 43, in which the filter strand 41 is not yet enclosed by the wrapping paper, a light guide head 21 is provided which is part of an optical measuring device 19 (see FIG FIG. 4 ) for detecting the segments 17 in the filter strand 41 and / or for detecting marks 30 on the inside of the wrapping paper 39 is. The fiber optic head 21 is advantageously attached to the hold-down 20, so that due to the fixed spatial relationship between the filter strand 41 and the hold-down 20 also a fixed spatial relationship between the optical fiber head 21 and the filter strand 41 is made. For fixing the optical fiber head 21 to the plate-shaped holding-down device 20, it is possible, for example, to provide a holder 15 which is attached to the holding-down device 20 and extends perpendicular to it. The light guide head 21 is advantageously guided at an angle in the range between 0 ° and 90 °, more preferably between 30 ° and 60 °, even more preferably between 40 ° and 50 °, through an opening 16 in the hold-down 20 (see FIGS. 4, 5 ), which allows a particularly space-saving arrangement.

The light guide head 21 comprises a, for example, pin-shaped or tubular housing 22, in which light guides 25, 31, 37, 50 to be explained later are arranged. The pin shape results in an optimal small design and high stability and protection for the light guides 25, 31, 37, 50. In the case of a product jam, the hold-20 including optical fiber head 21 and the flexible light guides 25, 31, 37, 50 hinged to the side.

For detecting differences, in particular color differences, on the shell side of the filter strand 41, which are caused in particular by transitions between the segments 17 in the filter strand 41, the light guide head 21 comprises a first light exit 23 (see FIG Figures 3 and 5 ), through which a directed on the shell side of the filter strand 41 first light beam or light cone 24 emerges.

The first light beam 24 is preferably vertically, or substantially vertically in the range of + - 20 °, directed downward and arranged so that it preferably meets centrally of the segments 17 of the filter strand 41. To generate the first light beam 24, a first transmission optical fiber 25 is provided (see FIG. 4 ), which extends from the first light outlet 23 in the interior of the housing 22 and is connected for example via a cable 26 to a remote light source 27. The light source 27 may be any suitable source of visible light, an infrared source and / or UV source.

The first light exit 23 is formed by an end face of the first transmit light guide 25, which at a suitable angle preferably in the range between 30 ° and 60 °, more preferably in the range between 35 ° and 55 °, even more preferably in the range between 40 ° and is inclined 50 ° towards the measuring head axis. The light emerging from the first light exit 23 of the first transmission light guide 25 falls directly and directly, ie without interposed optical elements, such as lenses, filters, etc., onto the surface to be examined, here the lateral surface of the filter strand 41 or the segments 17. It is not excluded that the housing 22 has a transparent, the first light exit opening 29 occlusive exit window.

The light reflected by the surface to be examined falls on a first light entrance 28, which may be arranged adjacent to the first light exit 23. It is thus a punctiform and / or rectangular reflection measurement. The first light outlet 23 and the first light inlet 28 are advantageously arranged together in one and the same outlet opening 29 of the measuring head 21 or of the measuring head housing 22.

A first receiving optical fiber 31 is associated with the first light inlet 28, with which the reflected light entering the measuring head 21 through the first light inlet 28 is directed to a remote optical sensor 32, in particular in the region of the light source 27, in order to obtain a light from the Intensity of the reflected light dependent electrical signal to produce.

The optical sensor 32 is suitably tuned to the measurement wavelength of the light source 27. It may preferably be a contrast or color sensor. A luminescence or infrared sensor can also be used according to the requirements. In principle, all sensor principles can be advantageously used, which can be physically combined with optical fibers or combined in other ways. By variable length of the light guides 25, 31, 37, 50, the sensor 32 can be installed appropriately at a suitable location.

For detecting markings or print marks 30 on the inside of the wrapping strip 39, the light guide head 21 comprises a second light outlet 35 (see FIG Figures 3 and 5 ), through which a second light beam or light cone 36 directed onto the inside of the wrapping strip 39 exits.

The second light beam 36 is preferably laterally directed approximately horizontally in the range of + - 20 ° and arranged so that it preferably strikes the wrapping strip 39 approximately perpendicularly. For generating the second light beam 36, a second transmitting light guide 37 is provided (see FIG. 4 ), which extends from the second light exit 35 inside the housing 22 and is connected for example via the cable 26 to the light source 27 (or a suitable further light source).

The second light exit 35 is formed by an end face of the second transmitting light guide 37, which at a suitable angle, preferably in the range between 30 ° and 60 °, on is preferably inclined in the range between 35 ° and 55 °, even more preferably in the range between 40 ° and 50 ° to the Meßkopfachse. Preferably, the light exits 23, 35 and the light beams 24, 26 form an angle in the range between 50 ° and 110 °, preferably between 60 ° and 100 °, more preferably between 70 ° and 90 ° to each other.

The light emerging from the second light exit 35 of the second transmitting lightguide 37 falls directly and immediately, i. Without intermediate optical elements, such as lenses, filters, etc., on the surface to be examined, here the inside of the wrapping strip 39. However, it is not excluded that the housing 22 has a transparent, the second light exit opening 13 occlusive exit window. The second light exit 35 is advantageously arranged below the upper edge of the wrapping strip 39, which allows a spatially optimal measuring arrangement.

The light reflected from the surface to be examined falls on a second light entrance 11, which may be arranged adjacent to the second light exit 35. It is also a punctiform and / or rectangular reflection measurement. The second light exit 35 and the second light entrance 11 are advantageously arranged together in one and the same outlet opening 13 of the light guide head 21 or of the housing 22.

The second light entrance 11 is associated with a second receiving optical fiber 50, with which the reflected light entering the light guide head 21 through the second light entrance 11 is directed to the optical sensor 32 (or a suitable further sensor) to reflect the intensity of the reflected light Light dependent, preferably electrical signal to produce.

The electrical signals are converted into a digital signal and transmitted to an electronic data processing device 34. In the data processing device 34, the signals are evaluated in order to derive therefrom the relative position and / or length of the individual segments 17, and / or a position and / or width detection of an inner mark 30 on the wrapping strip 39, as actual values for downstream monitoring - and to determine synchronization tasks. The evaluation can be done for example by determining one or more rising or falling signal edges. On the basis of the evaluated signals, process-dependent material processing, for example, cutting position control of the cutting device 47, detection of the object or segment length and position control can then be controlled and carried out automatically and online in the production process.

In one embodiment, an (error) signal may be generated when the relative allocation of a segment 17 to an inner marker 30 on the wrapper strip 39 exceeds or falls below given limits. The error signal can advantageously be used for ejecting defective articles, issuing a warning to an operator and / or for a machine stop.

The cone angle of the cone of rays of the light cone 24, 36 is preferably small, in particular smaller than 70 ° or 68 °, preferably smaller than 45 °, more preferably smaller than 30 ° and amounts to preferably 22 °. The shape of the light exits 23, 35 may vary and be, for example, round or angular. The light exits 23, 35 are preferably polished smooth and can therefore be easily cleaned, for example in Leimabsatz etc.

The optical measuring device 19 comprises the light source 27, the optical fiber head 21, the optical fibers 25, 31, 37, 50 and the optical sensor 32. The optical fiber technology used makes it possible to use any geometrical holders and guides with one or more optical detection points as online measuring device 19 to realize.

Instead of a light guide head 21 may also be provided a plurality of optical fiber heads. For example, a light guide head for a pair of transmit-receive optical fibers may be provided in each case. A separate fiber optic head for each light guide is not excluded.

Claims (15)

1. Strand forming apparatus (10) of the tobacco processing industry for producing multi-segment rods, including a continuously driven garniture tape (42) for conveying a wrapping strip (39) placed on the garniture tape (42) and a number of segments (17) placed on the wrapping strip (39), a wrap-around device (43) for enwrapping the segments (17) with the wrapping strip (39), and an optical measuring device (19) for detecting a property of the multi-segment strand (41) formed from the segments (17) and the wrapping strip (39), characterized in that the optical measuring device (19) includes at least one light outlet (23; 35) which in the conveying direction is located before the wrap-around device (43).
2. Strand forming apparatus according to claim 1, characterized in that the at least one light outlet (23; 35) is formed by at least one light guide (25; 37).
3. Strand forming apparatus according to any one of the preceding claims, characterized in that the measuring device (19) is configured to perform at least one punctiform and/or rectangular reflection measurement.
4. Strand forming apparatus according to any one of the preceding claims, characterized in that the measuring device (19) includes a first light outlet (23) which is located in correlation with the measurement of the segments (17).
5. Strand forming apparatus according to any one of the preceding claims, characterized in that the measuring device (19) includes a second light outlet (35) which is located in correlation with the measurement of the wrapping strip (39) .
6. Strand forming apparatus according to the claims 4 and 5, characterized in that the light outlets (23, 35) are arranged at an angle in the range between 0° and 180°, in particular between 50° and 110° to each other.
7. Strand forming apparatus according to one of the claims 4 to 6, characterized in that each light outlet (23, 35) is formed by an assigned transmitting light guide (25, 37), wherein preferably each transmitting light guide (25, 37) is provided with one receiving light guide (31, 50).
8. Strand forming apparatus according to any one of the preceding claims, characterized in that the at least one light guide (25, 31, 37, 50) is mounted in a light guide head (21).
9. Strand forming apparatus according to the claims 7 and 8, characterized in that the transmitting light guide (25; 37) and the corresponding receiving light guide (31; 50) are located in a common outlet aperture (29; 13) of the light guide head (21).
10. Strand forming apparatus according to claim 8 or 9, characterized in that the light guide head (21) is attached to a hold-down device (20) for holding down the segments (17) in the shaping garniture (45).
11. Strand forming apparatus according to claim 10, characterized in that the light guide head (21) is guided through an aperture (16) in the hold-down device (20).
12. Strand forming apparatus according to one of the claims 8 to 11, characterized in that the light guide head (21) is arranged to be inclined to the horizontal at an angle in the range between 0° and 90°, in particular between 30° and 60°.
13. Method for producing multi-segment rods of the tobacco processing industry, including conveying a wrapping strip (39) and a number of segments (17) placed on the wrapping strip (39) by a garniture tape (42), enwrapping the segments (17) with the wrapping strip (39), and optical detection of a property of the multi-segment strand (41) formed from the segments (17) and the wrapping strip (39), characterized in that the optical detection is carried out prior to enwrapping the segments (17) with the wrapping strip (39).
14. Method according to claim 13, characterized in that the electrical signals from the optical detection are evaluated to determine therefrom the relative position and/or length of the individual segments (17), and/or a position and/or width determination of an internal marking (30) on the wrapping strip (39), as actual values for a subsequent monitoring and synchronization function, for example control of the cutting point.
15. Method according to claim 13 or 14, characterized in that a signal is generated as soon as the relative assignment of a segment (17) to an internal marking (30) on the wrapping strip (39) exceeds or falls below predetermined threshold values.

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