EP3267367B1 - Counting disc device - Google Patents

Description

The invention relates to a device for processing sheets arranged in stack form according to the preamble of claim 1 and a method for using such a device.

Conventional counting disk devices can be designed to record the number of sheets arranged in stack form, which are, for example, printed sheets of notes of value, such as shares or banknotes or also stacks of such, already separated, notes of value. The disclosure EP 1 204 514 A1 describes a generic device comprising a base device for connection to a vacuum device for providing a vacuum, a light source and a counting disk which is rotatably arranged with the base device and can be optically coupled with it using vacuum technology. The counting disc comprises a plurality of circumferential sections, each separated by a radial opening, each with a tip or nose leading in the direction of rotation and a plurality of suction openings arranged on the underside. In this case, the device has an optical illumination path for illuminating at least a section of a sheet of the sheets arranged in stack form and an optical recording passage for receiving the light reflected and / or scattered by the illuminated sheet section. The known device is designed in such a way that the sheet section that is picked up via the optical recording path and illuminated by the illuminated section reflected or scattered light for determining a distance between a side edge of the respective sheet and a printed image or for generating a counting pulse.

The disclosure US 2007/0206192 A1 relates to an imaging system and a method for operating in different operating modes such as wide field microscopy or confocal microscopy of at least one sample. The system comprises at least one light source, an optical system geared to the operating mode of the microscope and a detector which is designed for the selective detection of pixels. The at least one sample is moved relative to the optical system using incremental or continuous movement of the sample. The disclosure DE 10 2007 047 468 A1 relates to a method and an arrangement for depth-resolved, optical detection of an illuminated sample, in which the sample or a part thereof is scanned by means of preferably linear illumination, and the illumination of the sample in the focus is periodically structured in at least one spatial direction, light coming from the sample are detected and images of the sample are generated, and an optical sectional image and / or an image with increased resolution is calculated from the sample. The disclosure EP 0 816 554 A1 relates to a method and an apparatus for processing a web printed with a pattern. The pattern recognizable on the web is recorded by an image capture device and image signals are generated which are fed to an image processing device and processed with the generation of control signals.

The invention has for its object to improve a generic device or its operation in terms of its functionality and / or its reliability.

This object is achieved by the present invention with a device having the features of claim 1. The device according to the invention is distinguished in that the lighting path for producing a linear lighting section are formed on the respective sheet and the receiving passage as an imaging passage for imaging the linear section illuminated on the respective sheet in a detection plane.

With the design of the device according to the invention, which is set up to produce a linear illumination section on the respective sheet and to depict this linear illumination section in a detection plane, the processing of the sheets arranged in stack form can be functionally improved and performed more flexibly. Furthermore, the error resistance of the counting process can be improved compared to the generic device with which, apart from the actual counting process, only a distance of a benefit (in particular a partial product in the form of a printed section on a printed sheet) from a sheet edge is determined, in particular to detect a cutting accuracy. In contrast to this, in addition to the actual use, the device according to the invention can also be used to record information such as, for example, a one-dimensional or multidimensional coding or a marking, and can be made available to a higher-level control device for further processing. The detection of such a code can, for example, provide unambiguous identification of a printed sheet. The term "coding" is to be understood in this respect in general and can in particular be an optically detectable feature such as a printed or otherwise introduced feature on or in the sheets of the sheet stack, i.e. Scrolling the stack of sheets.

The device according to the invention is suitable for processing any stack of sheets, the respective sheets being for example sheets of paper / cardboard or plastic film. The sheets can also be made of a composite material and / or be made in sections from different materials.

According to the invention, the term “detection plane” is to be understood in general terms and can include, for example, a planar or a curved plane or a section with planar and / or curved regions. In this case, for example, a sensor surface of an image sensor device, in particular a monochrome or polychrome photosensor, which can be designed to provide a captured image for digital further processing, can be used in this acquisition plane.

The expression “linear illumination section” can mean an approximately rectangular illuminated area in which the long edge has at least twice, in particular at least three times the extent of the short edge. It is within the scope of the invention if the edges are not completely straight, instead they can also be curved, in particular slightly curved. Also, these "edges" cannot represent a hard transition from the lighting section to the unlit areas, but a smooth transition.

The indication "illumination path" or "imaging path" denotes the respective optical arrangement for realizing the linear illumination section on the sheet or the illustration of this section in a detection plane.

Depending on the specific embodiment, the linear illumination section can be located directly behind the lower or the upper end face of the counting disk, since the sheet of the stack that has just been processed can rest on this end face at least in sections. In this respect, the indication "lighting section on the respective sheet" can mean a light field generated via the lighting path that Depending on the embodiment, it is located directly on the underside or directly on the top of the counter.

It should be noted that the terms light, light source, luminous flux density or illuminance are to be understood in general and do not necessarily have to be limited to the visible spectral range. In particular, an NIR laser can also be used as the light source, wherein all optical components in the illumination path or imaging path and the sensor device (s) can be adapted to this.

Further developments of the invention or further features according to the invention are specified in the general description, the description of the figures, the drawings and the subclaims.

The linear illumination section on the respective sheet or the light field generated directly below or above the counting disc by means of the functionality of the illumination path can be adapted in terms of its dimensions to the respective application. In order to provide a high resolution of the overall optical system comprising the illumination path and the imaging path, the width of the illumination line can be a few 5 μm, for example ≤ 80 μm or 50 50 μm, in particular ≤ 30 μm. On the other hand, it can be provided that the perpendicular extension of the lighting strip is in the range of approximately one to 10 millimeters or more, in particular approximately 5 mm or approximately 7 mm. The last-mentioned extent can be adapted to a dimension or dimensioning of a coding attached, in particular printed, on the sheet, in particular the same size or slightly larger, so that the coding can be completely captured by the lighting strip in a certain direction.

It can be provided that the overall optical system is set up in such a way that the linear illumination section is oriented essentially radially with respect to its longitudinal axis with respect to the counting disc, and thus the width of the illumination section is oriented essentially tangentially to the counting disc.

In one embodiment it can be provided that the optical system is set up such that the length / width ratio of the linear illumination section is 50 50, in particular insbesondere 100 or even oder 300.

The light source can in particular be arranged as a component in the base device. In other embodiments, however, the light source can also be coupled to the base device from the outside of the optical illumination path, for example via a light guide. Various configurations can be used as the light source itself, for example a halogen lamp with a high luminous flux or a gas laser. In a particularly expedient embodiment, the light source can be designed as a semiconductor light source, which can in particular be set up as a light source for emitting light of a first wavelength and light of a second wavelength.

In order to produce a linear illumination section on the sheet, the light source can expediently be coupled on the input side to the illumination passage, wherein the illumination passage can have a plurality of beam shaping elements in order to achieve the desired linear illumination section at the location of the respective sheet, i.e. to be provided in the end area of the lighting aisle.

In order to provide a simple supply to the light source and to an image sensor device arranged at the location of the detection plane, the following can expediently be provided: that the illumination path and the imaging path are arranged in sections in the base device and in sections in the counting disc, the image sensor device being coupled to the imaging passage, in particular in such a way that a photo sensor of the image sensor device is arranged in the specified detection plane. It can preferably be provided that the image sensor device is arranged in or on the base device.

In order to achieve a homogeneous luminous flux density (illuminance) at the location of the linear illumination section on the sheet, it can expediently be provided that the illumination path in the base device has at least one optical series connection of a Powell lens and a cylindrical lens. Such a system can be expanded by a further spherical lens, which is designed in combination with a negative cylindrical lens, as a converging lens and represents a beam expansion in the axis perpendicular to the cylinder axes. This lens in turn represents a collimator in the cylinder axis, which collimates the divergent radiation emitted by the Powell lens. Such optical series connections are particularly suitable when using the semiconductor light source described, in particular a laser diode, which, owing to its geometric structure, has widely different divergence angles in directions perpendicular to one another. A particularly effective symmetrization in the illumination aisle can be achieved in that two Powell lenses oriented perpendicular to one another are connected in series, whereby two cylindrical lenses can be optically connected in series, with the two cylindrical lenses optically connected in series with respect to each other with respect to their excellent axis are oriented vertically.

It can preferably be provided that in the lighting aisle Beam shaping elements are included to provide a planar and homogeneous light distribution in a predetermined plane of the illumination path, wherein this optical arrangement can be designed such that the predetermined plane is located in the area of the transition between the base device and the counting disc. In this respect, this level can be arranged in the area of the counter, the base device or exactly between the two, in any case, however, in the area of the transition from the base device to the counter, so that any faults present in this area have little effect, since the light is distributed homogeneously.

In order to provide a symmetrization of the light used for the illumination with respect to the optical polarization, it can advantageously be provided that the optical illumination path has a λ / 4 plate, which can preferably be arranged in the section of the illumination path within the base device. This λ / 4 plate can be oriented in the lighting aisle in such a way that the light emitted by the light source and propagating in the lighting aisle is circularly polarized after passing through the λ / 4 plate.

The lighting path in the device can preferably have an optical connection of a plurality of cylindrical lenses with different focal lengths in order to generate the linear lighting section on the sheet, in particular based on the planar and homogeneous light distribution in the predetermined plane of the lighting path. In this sense, the described planar and homogeneous light distribution is transformed from the optically connected cylindrical lenses into the linear field distribution to provide the linear illumination section on the sheet.

Depending on the specific properties of the sheets, in particular with regard to the reflection / scattering properties of the illuminated sheet surface or the illuminated printed areas, it can advantageously be provided that the lighting path and / or the imaging path has an optically effective filter device for filtering light with predetermined properties such as Polarization and / or wavelength. In addition to adapting the device according to the invention to the physical properties of the leaves or an applied, e.g. Printed coding can also be achieved by this measure in at least some of the embodiments that extraneous light is not detected or is only detected to a reduced extent, which otherwise could for example falsify the mapping of a two-dimensional code from the sheet onto a photosensor.

In particular, it can be provided that the illuminating aisle has a linear polarizer that can be arranged on the input side of the illuminating aisle section of the counting disk and that the imaging aisle has a linear polarizer that can be arranged on the output side of the imaging aisle section of the counting disk, the latter linear polarizer in relation can be oriented to the transmitted polarization perpendicular to the linear polarizer in the illumination aisle section of the counter.

To provide a compact structure, it can be expediently provided that the illumination path and the imaging path have at least one common optical element, which can be arranged on or in the counting disc, the common optical element being in particular designed as a deflection prism.

The common optical element can preferably be designed and arranged to direct light from the illumination path to the linear illumination section of the sheet steer and pick up and / or scatter light reflected by the linear illumination section and redirect it into the imaging path.

To close the lighting path and the imaging path with respect to dust and / or moisture on the end on the face of the counter disk which is directed towards the sheet, a transparent plate, in particular comprising two flat interfaces, can advantageously be provided, which advantageously closes both the lighting path and the imaging path. Such a transparent plate can be designed, for example, as a sapphire plate, which has good optical transmission properties and high hardness.

In such embodiments, in which a prism at the end of the sheet both directs the illuminating light onto the sheet and also receives the reflected and / or scattered light, both this plate and the prism inside the plate in the counting disc can have common optical elements of the lighting path and the course of the illustration. It can also be expediently provided that the illumination path and imaging path on the opposite end faces of the base device and the counter disc are each closed off by a corresponding optical plate, in particular by a plate made of sapphire. It should be pointed out that the end plates do not necessarily have to have two flat boundary surfaces; in special embodiments, it may also be expedient to design the plates with a spherical surface or a spherical surface for directing light, in particular as a cylindrical lens.

It can also be provided that an optical component arranged in the imaging aisle or illumination aisle simultaneously serves as a protective or termination window for the respective illumination aisle or imaging aisle section in FIG the counter or the basic device. Such a component can in particular be an optical polarizer.

In order to image the linear section illuminated on the sheet, the imaging path can have at least one imaging stage with light-refractive optical elements for generating an image of the linear, illuminated sheet section in the detection plane, the detection plane being able to lie in the imaging duct section of the base device. This constructive measure ensures that an image capturing device, for example a photo sensor, can be arranged outside the rotating counting disk, which simplifies the electrical supply and the forwarding of the acquired data.

In order to keep the space requirement for the imaging path in the counting disk and / or the base device small, it can be provided that the imaging scale of the at least one imaging level is less than or equal to 1, in particular approximately 0.6. Insofar as the imaging path has a plurality of imaging stages connected in series, it can be provided that the imaging scale of the entire imaging path is 1 1, in particular ≤ 0.5 or, in certain versions, is also 0,2 0.2.

In order to achieve an optimal adaptation of the geometric conditions, in particular with regard to the dimensions of the counting disk and base device and the imaging path running therein, the imaging path can expediently comprise an imaging stage with light-refractive optical elements for producing an intermediate image of the linear image section, the intermediate image in the imaging passage section of the basic device. To improve the transfer of the intermediate image to the detection level, provision can be made to arrange a screen at the location of the intermediate image.

In another embodiment it can also be provided that the imaging path comprises a single imaging stage with light-refractive optical elements for generating the image of the line-shaped image section, wherein this image can lie in the imaging path section of the base device, and a sensor surface of an image sensor device can be arranged at the location of the image plane can.

An imaging stage in the imaging path can comprise at least one cylindrical lens, in particular an optical series connection of two cylindrical lenses. Insofar as the generation of an intermediate image is provided in the imaging process, a second imaging stage can be provided in the functionality of an objective for generating an image in the detection plane.

For optimal use of the light received in the receiving aisle, it can be expediently provided that a lens is arranged at the location of the intermediate image for imaging an exit pupil of the first imaging stage into an entrance pupil of the second imaging stage.

The device according to the invention can preferably have a control device for controlling the exposure of an image sensor device arranged at the location of the detection plane (image plane) with respect to its sensor surface. In particular, it can be expedient if the control device is set up to determine the start time of the exposure and the end time of the exposure, in particular for detecting the time period within which the linear illumination section depicted in the detection plane falls on the sensor surface. For this purpose, the control device can expediently be connected on the input side to the output of at least one optical sensor, such as a photodiode, for detecting the alignment of the lighting aisle section of the base device with the respective one of the lighting aisle sections the counting device.

For simple assembly of the optical components of the respective lighting aisle section and / or of the respective imaging aisle section in the counting disk and / or the base device, it can be expediently provided that the respective optical components are attached to a respective carrier, e.g. are glued and the respective carrier is inserted and fixed as a module or insert in assigned recesses in the counting disk or the base device. With this design, a comparatively simple pre-adjustment of the optical components on the respective carrier is provided before it is fastened in the counting disk or the base device.

The control device can preferably control the exposure of the image sensor device in response to an output signal of the at least one optical sensor such as a photodiode. The at least one optical sensor can be part of a light barrier that also has a light source. In a further embodiment, which does not require a further light source, light from the illuminating light source can be detected via an optical sensor, such as a photodiode, shortly before alignment of the illuminating aisle sections of the basic device and the counting device rotating relative thereto, so that the starting time of the exposure is thereby determined can be. In one embodiment, starting from this start time, the end time of the exposure of an image sensor can be determined via a calculation, in particular as a function of the rotational speed of the counting disk.

In order to provide the respective captured images for the sheets arranged in stack form for subsequent data processing, a storage device can expediently be used be provided, which feeds a data processing device.

In order to provide a particularly expedient processing of the sheets arranged in stack form, it can be provided that the captured image has an at least two-dimensional code, in particular a QR (Quick Response) code or a data matrix code, the data processing device for decoding the at least two-dimensional Code in the captured image of the coding can be set up. In one embodiment, it can also be provided that this code is a three-dimensional code, for example in that a two-dimensional code is designed, in particular printed, as a colored code that is detected in a color-sensitive manner. Correspondingly, provision can be made for this to print such a code on the sheets arranged in stack form that can be optically recorded with the device according to the invention and subsequently digitally processed.

In order to control the illuminance in the detection plane (image plane), it can expediently be provided that the control device is designed to set or control or regulate the optical output power of the light source of the illumination path.

In addition to counting the sheets arranged in stack form, the device according to the invention is also suitable for detecting one- or multi-dimensional codes, for example 2D or 3D codes, which can be attached, in particular printed, on the sheets arranged in stack form. This property of the device according to the invention can be expedient in particular in a sheet processing system, in particular if this coding represents a unique identifier for identifying the respective sheet.

The use of the device according to the invention for detecting a coding, for example in the form of a barcode applied to the sheet, has the advantage of increased error security compared to conventional detection devices. It can be provided that the linear illumination section on the sheet is aligned approximately perpendicular to the bar code lines and extends over all lines of the code. When the counting disc is rotated, the geometric relationships with respect to the course of the linear lighting sections can be set such that several sections of the entire bar code are imaged on the image sensor surface, which increases the resistance to errors when using the device according to the invention, since all of the linear lighting sections shown are shown include the entire barcode.

The above object is further achieved by a method for processing sheets arranged in a stack comprising a base device to which a vacuum device for providing a vacuum is connected, and a counting disk which is rotated to the base device and is intermittently coupled with it in terms of vacuum technology and optics. In this case, a linear illumination section is generated on a sheet of the stack by means of an illumination passage extending through the counting disk and imaged in a detection plane by means of an imaging passage extending through the counting disk. With the method according to the invention, in particular a flat coding or other marking or features applied to the sheets can be detected with high accuracy and resolution.

In order to detect a coding applied to the sheets in each case, it can preferably be provided that a plurality of images of linear lighting sections are recorded in the detection or image plane and for recognition a coding on the sheet can be processed. This plurality of images result from the fact that the respective illumination line sections are mapped into different areas of the detection plane, that is to say, for example, into different areas of the sensor surface in the course of the scanning of the coding, since the imaging aisle section in the counting disk moves relative to the imaging section in the base device. This measure also enables high-resolution coding, which can have dimensions of several mm ² , in particular several 10 mm ² .

Figur 1a

in einer perspektivischen Ansicht eine erfindungsgemäß ausgebildete Zählscheibenvorrichtung zusammen mit einem zu verarbeitendem Blattbogenstapel unter Angabe der Drehrichtung der Zählscheibe,

Figur 1b

die Vorrichtung gemäß Figur 1a mit um einige Grad weitergedrehter Zählscheibe,

Figur 1c

die Vorrichtung gemäß Figur 1b mit um einige Grad zu der in Fig. 1b angegebene Betriebssituation weitergedrehter Zählscheibe,

Figur 2

die im Beleuchtungsgang und im Abbildungsgang der erfindungsgemäßen Zählscheibenvorrichtung gemäß Fig. 1a angeordneten optischen Elemente in einer perspektivischen Prinzipansicht,

Figuren 3a - c

eine Abfolge von perspektivischen Unteransichten auf die Zählscheibe bei unterschiedlichen Drehpositionen der Zählscheibe,

Figur 4

eine perspektivische Aufsicht auf die Zählscheibe mit entfernter Basiseinrichtung und

Figur 5

eine perspektivische Unteransicht auf die Basiseinrichtung bei entfernter Zählscheibe

zeigt.The invention is explained below by describing some embodiments with reference to the accompanying drawings, wherein

Figure 1a

a perspective view of a counting disk device designed according to the invention together with a sheet sheet stack to be processed, specifying the direction of rotation of the counting disk,

Figure 1b

the device according to Figure 1a with the counter turned a few degrees,

Figure 1c

the device according to Figure 1b with a few degrees to the in Fig. 1b specified operating situation of turned counter,

Figure 2

that in the illumination aisle and in the imaging aisle of the counting disk device according to the invention Fig. 1a arranged optical elements in a perspective principle view,

Figures 3a-c

a sequence of perspective bottom views on the counter at different rotary positions of the counter,

Figure 4

a perspective view of the counter with the base device removed and

Figure 5

a perspective bottom view of the base device with the counting disk removed

shows.

The device according to the invention is explained below with reference to the design of a counting disk device according to the invention, in which a stack of sheets is counted and at the same time an optically detectable feature of the respective sheet is recorded. Figure 1a shows a perspective view of an embodiment of this counting disk device designed according to the invention, comprising as essential components a base device 10, which is also referred to in the field as a transfer block, and a counting disk 20 that is coaxially aligned and rotatable with respect to the base device. The base device 10 is relative to the counting disk 20 in Operation stationary. For clarity of illustration, the figure does not show the vacuum generating device flanged to the base device 10 in the described embodiment, for example a vacuum ejector working according to the Venturi principle or a vacuum pump. Also not shown is a drive shaft for rotating the counting disk 20 relative to the stationary base device 10, the drive shaft extending through the drive shaft feedthrough 100 of the base device and being rigidly flanged to the counting disk 20 after its assembly.

The base device 10 standing for the counting disk is via the counting disk shaft (not shown) and the adapter 102 fixed, wherein the base device rests axially spring-loaded on the counting disc. In the described embodiment, the vacuum generation device (not shown) for supplying suction air is flanged on via a vacuum connection (also not shown) of the base device. Reference numeral 101 denotes a housing section for receiving a control board and connections for connection to a central control.

The counting disk device according to the invention is initially set up to determine the number of sheets 41 arranged on a sheet sheet stack 40. For this purpose, the counting disk 20 in the described embodiment has three circumferential sections 200a, b, c, each separated by a radially running opening 203, that is to say with a radial directional component, each circumferential section having a tip or nose 201 that leads in the direction of rotation D and an end region with a trailing hold-down device 202. In the in Figure 1a Perspective view of the counting disc 20 specified is provided on the top of the respective tip 201 test hole bores 204 for detecting an operating situation in which a sheet strokes over these test bores and thus covers them. In operation, the counter device as in Figure 1a specified, applied overlapping to a stacking corner, the entire device 1 for the counting process being moved axially downward when the counting disc 20 is rotating. In the present application, the term “hole”, “hole” or “opening” is to be understood generally and is not restricted to circular designs, but also includes non-round designs.

In order to separate the sheets, the peripheral sections 200a, b, c have bores which can be subjected to a vacuum on the underside, as a result of which the bores lying against the underside of the respective peripheral section 200a, b, c Sheet is sucked in, so that it can be guided on the upper side by the leading tip of the circumferential section 200b, c, a following in the direction of rotation. Further explanations on the functioning of the counter are given below with reference to the Figures 3a-c .

Out Figure 1a In addition, an illumination path 30a and an imaging path 30b can be seen, which in the embodiment described extend in sections both in the base device 10 and in the counting disc 20.

Both the illumination aisle 30a and the imaging aisle 30b have an optical series connection of a multiplicity of optical components, with the illustration according to FIG Figure 1a it was dispensed with specifying the attachment of the optical components in the respective sections of the base device 10 or counting disk 10. In a manner yet to be explained, in the described embodiment, the light emitted by a semiconductor laser at multiple relative rotational positions between the base part 10 and the counter disk 20 is transmitted from the base device into one of the three illumination aisle sections of the counter disk and from there to the underside of the counter Counter disc facing surface of a sheet 41 thrown. The lighting path is designed with respect to the design and arrangement of the optical components in such a way that a linear section on the sheet 41 is illuminated. The light components scattered or reflected by the illumination section enter a receiving passage on the underside of the counting disk and are guided to a sensor surface 490 of a camera 500 via one of the imaging passage sections in the counting disk and the imaging passage section of the base device 10. To this extent, the illuminated section optically depicts the illuminated section on the sheet on the sensor surface of camera 500.

The counting disk for each of the peripheral sections 200 each has an associated lighting aisle section and an associated imaging aisle section, the lighting aisle sections and the imaging aisle sections for all peripheral sections of the counting disk in the described embodiment being constructed identically, in particular having the same optical elements.

By rotating the counting disk relative to the base device, the lighting section running in the base device and the imaging section running in the base device are aligned simultaneously with the respective lighting section and the respective imaging section of one of the peripheral sections of the counting disk, so that a section of a sheet is illuminated in a linear manner and the illuminated sheet section is opened the sensor surface of the image sensor device can be imaged.

The line-shaped light section generated by the illumination path on the sheet slides over a predetermined section on the sheet by the rotation of the counting disk toward the base device, the image of the line-shaped light section in the same way, but scaled with the image scale provided by the image path, over the sensor surface of the image sensor device running.

The counting disk device according to the invention is designed, in particular, to detect a code applied to the sheet, for example a 2D coding, which simplifies the processing of the sheets arranged in a stack. For example, each of these sheets or sheet sheets can have a surface section at the same point in the area of a corner, on which the said coding, for example a 2D coding, is applied, in particular printed. It can be provided that the linear illumination section generated on the sheet via the illumination path only partially covers the flat code at a predetermined point in time, the linear encoding section on the sheet rotating the counting disk to encode the flat code within a time period which is of the dimensions depends on the coding and the speed of rotation of the counter.

• Figur 1 a zeigt eine Situation, bei welcher das oben liegende Blatt 41 des Blattbogenstapels 40 an der Unterseite des Umfangsabschnittes 200a mittels Unterdruck-beaufschlagten Bohrungen angesaugt und somit vom Stapel 40 abgehoben wird.
• Figur 1b zeigt die Situation kurze Zeit später, nachdem die Zählscheibe 20 geringfügig in Drehrichtung D weitergedreht ist und die vorlaufende Spitze 201 des Umfangsabschnittes 200b, welcher dem Umfangsabschnitt 200a in Drehrichtung nachfolgt, untergriffen wird. Die Spitze 201 weist ausgehend von der Spitze eine Schräge auf, sodass das Blatt 41 diese Schräge hinaufgleitet und die drei Prüflochbohrungen 204 abdeckt. Diese Situation wird in noch zu beschreibender Weise in der beschriebenen Ausführungsform genutzt, um ein Zählsignal zu erzeugen, sodass hierüber die Anzahl der im Stapel 40 befindlichen Blätter ermittelt werden kann.
• Figur 1c zeigt die Situation etwas später nach der Weiterdrehung der Zählscheibe 20 ausgehend von der Situation gemäß Figur 1b, wobei das Blatt 41 nun vollständig auf der Oberseite des Umfangsabschnittes 200b aufliegt und das im Stapel 40 darunter liegende Blatt von der Unterseite des Umfangsabschnittes 200b angesaugt wird, sodass es dann nachfolgend von der vorlaufende Spitze 201 des Umfangsabschnittes 200c untergriffen werden kann.

In an embodiment that is not shown, the counting disk device according to the invention can also be designed to detect a 3D coding applied to the sheet, wherein the coding can again be a flat printed image, but here it is colored. It can be provided accordingly to use a poly-colored light source and a polychrome image sensor in order to detect the color coding.

• Figure 1 a shows a situation in which the top sheet 41 of the sheet sheet stack 40 is sucked into the underside of the peripheral section 200a by means of bores under vacuum and thus lifted off the stack 40.
• Figure 1b shows the situation a short time later, after the counter disk 20 has been turned slightly in the direction of rotation D and the leading tip 201 of the peripheral portion 200b, which follows the peripheral portion 200a in the direction of rotation, is reached. The tip 201 has a slope starting from the tip, so that the sheet 41 slides up this slope and covers the three test hole bores 204. This situation is used in a manner to be described in the described embodiment in order to generate a counting signal so that the number of sheets in the stack 40 can be determined in this way.
• Figure 1c shows the situation a little later after the rotation the counting disc 20 based on the situation Figure 1b , wherein the sheet 41 now rests completely on the top of the peripheral portion 200b and the sheet underlying it in the stack 40 is sucked in from the underside of the peripheral portion 200b, so that it can subsequently be gripped by the leading tip 201 of the peripheral portion 200c.

How from Figure 1c As can be seen, the sheet 41 in the vicinity of the corner formed by the sheet edges 42, 43 has printing in the form of a 2D coding 45, which is recorded in a manner to be described in detail before the sheet 41 is sucked on to the underside of the peripheral section 200a was read by illuminating a line-shaped section of the coding and imaging this illuminated section on a sensor surface of the camera 500.

Regarding Figure 2 The entire structure of the lighting path and the imaging path and thus the detection of the 2D coding 45 applied to the sheet is to be explained below. Figure 2 shows a schematic representation of the optical structure of the illumination path 30a and the imaging path 30b with their respective optical components, the base device 10 and the counting disk 20 being indicated only by borders for clarity of the illustration, so that the respective lighting path and imaging path sections in the base device and the Counting device are recognizable. For each of the three peripheral portions 200a, 200b, 200c included in the present embodiment of the invention, see Figure 1a , the counting disk 20 has an associated illumination aisle section and an associated imaging aisle section for completing the illumination aisle or the imaging aisle. In this respect shows Figure 2 only one of the total of three illumination path / imaging path sections arranged in the counting device in an operating situation in which the aisle sections from one of the peripheral sections of the counting disk 20 are aligned with the aisle sections of the base device 10.

In the embodiment described, the illumination aisle section completed as described has a laser diode 300, which is followed by a collimator lens 310. The light is deflected through 90 ° by a deflecting mirror 320 and passes through a λ / 4 plate 330 aligned with the light, so that the illuminating light is then essentially circularly polarized. In order to homogenize the light emitted from a strip structure of the laser diode, the light passes through two Powell lenses 340a, 340b connected in series, which are rotated by 90 ° with respect to their apex lines to the optical axis and whose complex, two-dimensional aspherical roof design matches the asymmetrical illuminated surface of the Laser diodes are adapted to lower the light density in the central area and to increase it in the peripheral area.

This is followed by a first series connection 350 of two cylinder lenses and a second series connection 360 of two cylinder lenses in the lighting aisle, the cylinder lens pairs being oriented perpendicular to one another, as shown in the figure, ie the refraction directions are offset by 90 ° to one another. As a result of the optical components of the illumination path 30a described so far, a homogeneous field distribution in the form of a plane wave is generated in the region of the transition between the base device 10 and the counter disc 20. Depending on the specific embodiment, this level can lie in particular in the region of the transition in the base device 10 or the counting disk 20.

To protect the optics in the lighting aisle, both the base device 10 and the counting device 20 have protective windows in the form of plane-parallel plates 370 and 401 at the end of the respective lighting aisle sections. These protective windows complete the lighting aisle and protect the optical components against dust and moisture. Depending on the embodiment, the windows can be made of different materials, e.g. plate 450 made of N-BK7 and plate 401 due to contact with the blades in operation made of an optical material of great hardness, e.g. made of sapphire.

The light entering the counter disk 20 is polarized via a polarizer 375, so that the illuminating light transmitted in the counter disk is linearly polarized. The light, which is essentially vertical with respect to the optical axis, is deflected by 90 ° by a mirrored deflection prism 380, which has a mirrored hypotenuse surface, is focused via two cylindrical lenses 390a, 390b and is deflected via the deflection prism 400 with a mirrored hypotenuse surface the coding 45 is deflected so that a linear illumination area is created on the section 45. In the described embodiment, the width of the illuminated section is approximately 20 μm, while the perpendicular dimension of the lighting strip is a few millimeters, in particular approximately 7 mm.

It should be pointed out that the series connection of cylindrical lenses 350, 360 and 390a, b in embodiments not shown can also be replaced by a single cylindrical lens.

In addition, the representation of the Figure 2 also that provided in the described embodiment below the deflecting prism 400 for completing the lighting path Protective window in the form of a plane-parallel plate 401, here a sapphire plate, which is cemented onto the deflecting prism in the embodiment described.

The line-shaped illumination section on the sheet scatters and / or reflects light, a part of this reflected and / or scattered light falling back via the sapphire plate 401 into the deflection prism 400 in the imaging path identified by reference symbol 30b. In the described embodiment, the imaging path has a first imaging stage, comprising three cylindrical lenses 410a, b, c, which image the linear illumination section on the coding 45 in an intermediate image plane, which in the described embodiment lies in the base device 10. For this purpose, the light in the counting disk is first directed upwards towards the base device 10 via a deflection prism 430, which has a mirrored hypotenuse surface, and passes through the polarizer 440 which is arranged directly behind the deflection prism 430 and which is oriented perpendicular to the polarizer 375 with respect to its transmission direction is. In this respect, in the described embodiment, the light falling on the coding 45 is polarized perpendicular to the light subsequently transmitted to the polarizer 440.

Also in the imaging process, the merging imaging sections of the counting device and the base device in the described embodiment are each closed off to protect against contamination and moisture. While this function is provided in the counting disk 20 by the polarizer 440, the imaging path section of the base device in the direction of the counting disk is closed off by a plane-parallel plate 450, here made of N-BK7.

After the transition to the basic facility is nearby In the intermediate image generated by the cylindrical lenses 410a, b, c, a field lens 460 is arranged, which images the exit pupil of the first imaging stage into the entrance pupil of a second imaging stage 480. In the embodiment described, this second imaging stage acts as an objective, which images the intermediate image at the location of the focusing screen 470 on a sensor surface 490 of a camera. In an embodiment not shown, provision can also be made to arrange the focusing screen 470 on the field lens 460, in particular to cement it on, and to place this optical interconnection at the location of the intermediate image.

In the same way as the linear illumination section in the described embodiment only covers part of the 2D coding 45, this covers the two imaging levels in the detection plane, i.e. image thrown onto the image sensor 490 only a part of the photosensitive surface of the image sensor 490. As the counting disc 20 rotates, the linear illuminated area on the paper side facing the underside of the counting disc sweeps over the entire coding, so that the illumination section imaged on the image sensor covers the area of the image sensor 490 in the same way, so that the entire 2D coding within a predetermined period of time is imaged on the image sensor 490.

With regard to the Figures 3a , b and c The sequential sequence of detecting a 2D coding, sucking the sheet into a throat-shaped cavity and then gripping the sheet under a leading tip 201 of a peripheral section by the counting disk device according to the invention is to be explained in more detail below. Figure 3a shows a perspective bottom view of the counting disk device according to the invention, ie essentially on the underside of the counting disk 20. The peripheral sections 200a, b, c can also be seen in relation to their undersides constructed identically. Between the respective leading tip 201 and the respective trailing hold-down device 202 are circumferentially spaced sections 210, 211, 212 of suction bores, the suction bores of section 212 being arranged in a direction towards the leading and directly adjacent tip 201, which in the described embodiment are formed as a recessed groove 205. The design of these depressions, in particular their depth, can be adapted to the rigidity of the stacked sheets to be processed, for example sheets of paper / cardboard or foil. The depth of the depression can expediently be set approximately inversely proportional to the rigidity of the arches.

In the described embodiment, each circumferential section is also assigned an optical insert 213 which closes with the underside of the counting disk 20, which is inserted into the counting disk in this circumferential section and has an opening which is closed by the plane-parallel optical plate 401. For clarity of presentation, see Figure 3a the insert 213 is provided with a reference symbol only for the peripheral section 200a, while the sections of the suction bores are provided with a reference symbol only in the peripheral section 200c. As explained and can be seen from the figure, all three peripheral sections are constructed identically in the described embodiment. This respective optical insert 213 comprises a carrier on which the optical components of the respective illumination aisle section and the imaging aisle section of the counting disk 20, see Fig. 2 , are fastened, the respective carrier being inserted into a recess provided in the counting disk in the respective peripheral section 200a, b, c. In this respect, such an optical insert 213 provides the illumination and the associated imaging aisle section for one of the peripheral sections 200a, b, c of the counting disk 20 represents.

The drive shaft bushing 214 can also be seen in the counting disk for receiving the drive shaft (not shown), which in the assembled state is firmly connected to the counting disk 20 rotating with respect to the base device 10. A driver arranged on the drive shaft engages in the driver bore 215 to define a defined rotational orientation between the counter disk and the drive shaft.

In an embodiment that is not shown, the counting disc can also have fewer or more peripheral sections, for example four or five, instead of three, which in turn can be designed identically and similarly to the embodiment described, in particular with three circumferentially spaced sections of suction bores that lie between a leading tip 201 and a trailing hold-down device 202 can be arranged. As the person skilled in the art recognizes, the counting rate can be increased by increasing the number of said peripheral sections on the counting disk while the rotational speed remains the same.

Figure 3a shows a situation in which the sheet 41, which is opposite to the underside of the counting disk 20 on the stack 40, was previously sucked in by section 210 of the peripheral section 200a and then covered and sucked over the section 211 by suction bores, the on the sheet applied 2D coding 45 has not yet passed over the optical plate 401, ie the code has not yet been detected by the counting disk device designed according to the invention.

End plate 401 provides access to the respective illumination aisle sections and imaging aisle sections that run within the counting disc, here respective flat, plane-parallel optical plate 401 in front of the deflection prism 400, see Figure 2 , is arranged, ie closes the illumination aisle section and the imaging aisle section in the respective circumferential section 200a, b, c.

In the described embodiment, the orientation and arrangement of the optical components is carried out in such a way that the linear illumination section on the sheet 41 extends essentially radially to the counting disk with respect to its longitudinal extent. In the described embodiment, this illumination section runs centrally to the optical plate 401 and extends in the radial direction essentially over its entire optically effective extension. In contrast, the lighting section extends vertically in the radial direction, i.e. tangential only over a fraction of the extent of the optical disk.

When the counting disc continues to rotate in the specified direction of rotation D, the optical plate 401, or rather the linear illumination section, is pivoted over the 2D coding 45 of the sheet 41. Figure 3b shows the operating situation in which the coding, which in the described embodiment is designed as a data matrix code with an area of 6.5 × 6.5 mm ² , lies just inside the optical plate 401. At the same time, the sheet 41 is sucked through the suction holes within the sections 211, 212. In the in Figure 3b Although the 2D situation 45 is in the indicated situation, it is essentially completely within the optical plate, but in this situation, too, the area of the coding 45 lying in the region of the center of the optical plate 401 is imaged on the sensor surface 490, so that the coding is scanned over the respective sections are imaged in different areas of the sensor surface, since the imaging aisle section in the counting disk moves relative to the imaging section in the base device.

Figure 3c shows one according to the situation according to Figure 3b an operating situation which follows shortly thereafter, in which the edge 42 of the sheet 41 is located shortly in front of the leading tip 201 of the section 200b. At the same time, the air suction bores act in section 212, so that the sheet is sucked into the fillet 205 in this area, so that the edge 42 in the viewing direction of FIG Figure 3c lies below the leading tip 201, so that it is picked up by it and then slides on the tip to cover the test hole bores 204, see Figure 1b . The test hole bores, like the suction bores, are subjected to negative pressure, wherein a cycling of the negative pressure maintained by the sheet cover into the base device is detected and can be processed as a counting signal by a control device.

As explained above, the vacuum is coupled in, i.e. the suction air supply, into the counter disk 20 rotating towards the base device and the coupling of the illuminating light into the respective illumination aisle section of the counter disk and the image capture in or on the base device by providing areas on the respectively assigned end faces of the base device and the counter disk, for example To couple suction bores and imaging sections or lighting sections of the counting disc 20 with those of the base device 10 at predetermined times and intermittently. This coupling takes place in that the respective areas such as bores overlap due to the relative rotation of the counting disk to the base device at predetermined times, wherein in the described embodiment the counting disk rotates at a uniform speed during the entire detection process of the sheets of the stack.

The designs provided on the opposite end faces of the counting disc and the base device are discussed below with reference to the Figures 4 and 5 described. Figure 4 shows one with respect to the sheet stack 40 and the counting disk 20 Figure 1c identical situation, with the basic device removed. As a result, the designs provided on the upper end face of the counting disk 20 become visible.

As above with reference to Figure 1c , according to the in Figure 4 illustrated situation, a situation is shown in which the uppermost sheet 41 of the stack 40 has been received by the tip 201 of the peripheral portion 200b and slides upward at the tip over the test hole bores 204, the underlying sheet initially over the suction bores of the section 210 (please refer Figure 3a ) and is subsequently sucked in by the suction bores of section 211. These suction bores are continued inside the counting disk 20 and end on its end face to the base device 10 in the suction bores 220 for the section 210 and the suction bores 225 for the section 211. As the counting disk continues to rotate, the coding described is illuminated on the other Underside of the sheet lying on the counting disc, the illumination path section of the counting disc to the base device being closed off with the linear polarizer 375, and the associated imaging path section being closed off with the linear polarizer 440. As explained above, in the described embodiment both linear polarizers are on the respective optical insert 213, see Fig. 3a , attached, which is arranged in a corresponding recess in the counting disc 20.

After the coding has been recorded as described above, by continuing to turn the counter in the direction of rotation D, the sheet is sucked in via the suction bores in the groove 205 (see Figure 3a ) so that the sheet is lifted slightly from the stack. The assigned suction holes for section 212 are in Figure 4 designated in the center with reference numeral 240. As in Figure 3a - c indicated, all sections of the suction bores comprise a plurality of bore groups, each of which in the described embodiment is one of the in Figure 4 Open suction openings visible at the top of the counter. The circumferential section provided with the reference numeral 245 comprises a plurality of vacuum relief bores, which are effective in particular in the region of the groove 205 after the sheet has been gripped by the tip 201 of the circumferential section 200c. Counter 200 rotates from position Figure 4 further, the tip 201 of the peripheral portion 200c grasps the sheet, which then strokes the test hole bores 204 of the peripheral portion 200c to generate a counting pulse.

In the described embodiment, the test bores 204 are fed through the radially outer test hole entrance 250, which is arranged on the same radial circumferential line as the suction bores 225. Since the counting pulse generated by the cover of the test hole bores 204 is detected in the area of the base device by means of a pressure sensor (not shown) , the counter disc also has a test hole exit 255 on the front side to the basic device.

How from Figure 4 As can be seen, each of the three peripheral sections 200a, b, c has the connections described on its end face to the base device, so that one of the sheets is counted on each peripheral section and the coding applied to the respective sheet is detected on the peripheral section preceding in the direction of rotation. To determine the respective start time and end time of the exposure of the sensor surface to detect a coding, the counting disk in the described embodiment has two trigger markings 260, 261, which are associated with the Interacting light barriers facing the counter face of the base device.

Figure 5 now shows that according to the counter Figure 4 facing end face of the base device in a perspective view, so that with the reference to Figure 4 designs described corresponding designs are recognizable. In this respect, the suction bore 105 corresponds to the suction bores 225 and the test hole entrance 250 as a function of the rotational position of the turntable. The suction bores 106 correspond to the suction bores 220 and 240, the test hole exit 255 corresponds accordingly to the test hole entrance 110. The front ends of the lighting aisle section or are also visible its end plate 370 and the imaging aisle section or end plate 450.

The base device 10 also has an in Figure 5 unspecified optical insert. The latter comprises a carrier to which the optical components of the illumination aisle section and of the imaging aisle section of the base device are fastened, the carrier being inserted into a recess provided in the base device.

Also go out Figure 5 the two with the trigger markings 260, 261 on the front of the counter according to Figure 4 interacting light barriers 125, 126 emerge, the outputs of which are used to control the image sensor 490. In an embodiment that is not shown, it can also be provided that trigger markings are not arranged on the counting disk, but on another component that is also moved by the drive shaft.

In the described embodiment, the end face of the base device facing the counting disk has one Running surface for the counter disc made of a material that is soft to it, the optical end plates on the adjoining end faces of the base device and counter disc each being offset inwards to the running surface in order not to contaminate or even damage the optical windows.

In an embodiment not shown, the scanning of the coding of the sheets of the stack is not realized on the underside of the counting disk, but on the top of the counting disk, ie on the in the Figures 1a-c visible face of the counter.

In addition, it is within the scope of the invention to generate a respective counting signal by detecting the coding or marking applied to the sheets, so that in this embodiment the design of one or more test bores in the counting disc and the provision of an associated pressure sensor can be dispensed with. In this respect, the term "counting disc" used in this application is to be interpreted in general terms and means a disc rotating towards the base device (rotary disc), which is designed to differentiate or separate adjacent sheets on the sheet stack, so that on or in the sheets of the Stack of codings or features provided can be optically recorded and made available for further processing.

Reference list

1

Counter disc device

10th

Basic setup / transfer block

20th

Counting disc

30a

Lighting aisle

30b

Illustration gear

40

Sheet sheet stack

41

sheet

42, 43

Sheet edge

45

Coding, coding area

100

Drive shaft bushing of the basic device

101

Control board / connection housing

102

adapter

105, 106, 107

Suction hole

110

Test hole input, count signal input

125, 126

Photoelectric barrier

200a, b, c

Circumferential section

201

Leading tip

202

trailing hold-down device

203

Radial opening

204

Test hole drilling

205

Groove

210, 211, 212

Section of suction holes

213

Optical use

214

Drive shaft bushing in counter

215

Driver bore

220

Suction holes for section 210

225

Suction holes for section 211

240

Suction hole for section 212

245

Vacuum relief holes

250

Test hole receipt

255

Test hole exit

260, 261

Trigger marker

300

Laser diode

310

Collimator lens

320

Deflecting mirror

330

λ / 4 plate

340a, b

Powell lens

350, 360

Series connection of two cylindrical lenses

370

Plane parallel plate

375

Polarizer

380

90 ° deflection prism

390a, b

Cylindrical lens

400

90 ° deflection prism

401

Plane parallel plate

410a, b, c

Cylindrical lens

430

90 ° deflection prism

450

Plane parallel plate

440

Polarizer

460

Field lens

470

Focusing screen

480

Second imaging level, lens

490

Image sensor, sensor surface

500

camera

D

Direction of rotation

Claims (15)

1. Device for processing sheets (40) placed in the form of a stack comprising:

   - a base device (10) for connecting to a negative pressure device for making available a negative pressure, a light source as well as

   - a counting disc (20), rotatably arranged with respect to the base device (10) and that can be connected therewith optically and by means of vacuum technology that comprises a multitude of peripheral portions (200a, b, c), respectively separated by an opening extending in radial direction, each with a tip (201) leading in the direction of rotation, and a multitude of suction openings, wherein the device has an optical illumination path (30a) for illuminating at least one portion of a sheet (41) of the sheets (40) placed in the form of a stack and an optical reception path for receiving the light reflected and/or scattered by the illuminated sheet portion, characterized in that the illumination path (30a) is designed for producing a linear illumination portion on the respective sheet (41) and the reception path as an imaging path (30b) for imaging the linear portion illuminated on the respective sheet (41) in a detection plane.
2. Device according to claim 1, characterized in that the light source is coupled on the input side to the illumination path (30a) and the illumination path has a multitude of beam forming elements.
3. Device according to one of the claims 1 or 2, characterized in that an illumination path portion in the counting disc (20) has an optical series connection of several cylindrical lenses (390a, b) with different focal lengths for producing the linear illumination portion on the sheet (41) starting from the planar and homogeneous light distribution in the predetermined plane of the illumination path.
4. Device according to one of the claims 1 to 3, characterized in that the illumination path (30a) and/or the imaging path (30b) has an optically active filtering device for filtering light with a predetermined property as polarization and/or wave length.
5. Device according to claim 4, characterized in that the illumination path (30a) has a linear polarizer (375) that is placed on the input side of the illumination path portion of the counting disc (20) and the imaging path (30b) has a linear polarizer (440) that is placed on the output side of the imaging path portion of the counting disc (20), wherein the linear polarizer (440) is oriented with respect to the transmitted polarization perpendicularly to the linear polarizer (375) in the illumination path portion of the counting disc (20).
6. Device according to one of the claims 1 to 5, characterized in that the illumination path (30a) and the imaging path (30b) have at least one common optical element that is placed on or in the counting disc (20).
7. Device according to one of the claims 1 to 6, characterized in that the illumination path (30a) and the imaging path (30b) are closed on the end side on the counting disc front side turned to the sheet (41) by an optically transparent plate (401) that is common to the illumination path and to the imaging path.
8. Device according to one of the claims 1 to 7, characterized in that the imaging path (30b) for imaging the linear portion illuminated on the sheet (41) comprises at least one imaging stage with refractive optical elements for producing an image of the linear sheet portion in the detection plane, wherein the detection plane is situated in the imaging path portion of the base device (10).
9. Device according to claim 8, characterized in that the imaging path (30b) comprises an imaging stage with refractive optical elements for producing an intermediate image of the linear sheet portion, wherein the intermediate image is situated in the imaging path portion of the base device (10).
10. Device according to claim 8 or 9, characterized in that the at least one imaging stage comprises at least one cylindrical lens (410a, b).
11. Device according to one of the claims 8 to 10, characterized in that a second imaging stage (480) is provided in the imaging portion of the base device (10) for producing an image by imaging the intermediate image in the detection plane.
12. Device according to one of the claims 1 to 11, characterized in that a control device for controlling the illumination of the image sensor device is connected on the input side with the output at least of a photo sensor for detecting the alignment of the illumination path portion of the base device (10) with an illumination path portion of the counting device (20).
13. Device according to one of the claims 1 to 12, characterized by a storage device for storing each image detected by an image sensor device arranged at the location of the detection plane as well as a data processing device for data processing of the detected image.
14. Device according to claim 13, characterized in that the device is set up to detect an image of a bidimensional code and that the data processing device is designed for decoding the bidimensional code of the detected image.
15. Method for processing sheets placed in the form of a stack comprising a base device (10) to which a negative pressure device for making available a negative pressure is connected and a counting disc (20) that is turned to the base device (10) and that is intermittently optically coupled therewith and by means of vacuum technology, wherein a linear illumination portion is produced on a sheet of the stack by means of an illumination path (30a) extending through the counting disk and is imaged in a detection plane by means of an imaging path (30b) extending through the counting disc.

Images