EP1900665B1 - Determination of the coil core centre of a coil handling device - Google Patents

Abstract

The device has a gripper (1) with components (3-5) for gripping a bobbin, and a sensor device (2) attached to the gripper and comprising sensors for range finding (11-14, 21-24). An evaluating and control device (9) receives and processes signals from the sensor device. A positioning device (10) controls the evaluation and control device. The positioning device processes the handle, and sensors are spatially separated from each other in sensor group modules (2A, 2B). The modules are arranged around the components for gripping the bobbin. An independent claim is also included for a method for operating a bobbin handling device of a tobacco processing industry.

Description

The invention relates to a reel handling device, a machine of the tobacco processing industry with a reel handling device and two corresponding methods for operating a reel handling device.

On packaging machines, for example wrapping machines, packaging material, e.g. Paper, aluminum foil, plastic film or laminate foil, processed by rolls, also known as reels. These bobbins are brought by a Bobinenhandungsvorrichtung to a unwinding device and pushed onto this. Also for tobacco processing machines, e.g. Cigarette making machines, reels with paper are needed.

Out EP-A-1 157 952 is a device for handling of wound material webs, in particular Hüllmaterialbahnen for products of the tobacco processing industry, formed bobbins known. The bobbins are removed from a stack of bobbins, which is formed using intermediate layers, and transferred to a Bobinenaufnahme. For this purpose, a bobbin carrier is movably arranged on a portal relative to a bobbin stack provided on a pallet. The bobbin carrier is equipped with jaws for grasping the bobbins.

In WO-A-02/092483 For example, a method and apparatus for feeding reels or reels to a machine are disclosed. The rollers have a central hole, and it is determined whether at least one reference point of a gripping member or a handling device lies inside the hole of the roller. The roll is received by means of a gripping member when the reference point lies inside the hole of the roll. The reference point is determined, for example via a transmitting and receiving device on the gripping member. In particular, three such transmitting and receiving devices are used to position the gripping member relative to the hole of the roller.

US-A-5,608,818 describes a method for automatically picking up objects, eg paper rolls, by a robot with gripping member on a controlled articulated arm. A spatial coordinates determination of the object takes place by recording several images and then evaluating the frequency of the distribution of the pixels. From this, a theoretical center is determined, and the gripping member is correspondingly lowered onto the roller.

In DE 85 01 277 U1 discloses a device for unloading individual reels from a pad by means of a gripper, wherein on the base a plurality of bobbins in several rows next to each other and in several layers are stacked. The gripper can be moved in a plane on a height-adjustable frame by means of linear drives extending at an angle of 90 ° to one another. On the frame sensors are arranged, each detect the lying in a plane bobbins and control the height adjustment of the frame. On the gripper sensors for aligning the gripper are arranged to be detected each bobbin. The sensors consist of sensor pairs, of which one sensor has a smaller and the other sensor a greater distance from the central axis of the cylindrical housing of the gripper than the outer radius of the respective to be taken bobbin.

EP 0 577 986 A2 relates to a method and apparatus for gripping cylindrical objects, such as cylindrical core rolls. A self-propelled suction head is moved to a position which is coaxial with the central axis of an object by successively determining three different points on the outer envelope of the object by means of photosensors on the suction head. For this purpose, the linear movement of the suction head is stopped when a photosensor signals that it has detected the object, whereby the first point is fixed. Subsequently, the suction head is rotated with the sensors and so moves the other photosensors at other points on the envelope. The central axis of the object is calculated from the intersections

The object of the present invention is to improve the position detection of bobbins in a simple manner, so that it detects faster and more precisely, i. be taken.

The problem is solved by a reel handling device, in particular the tobacco-processing industry, comprising a gripper with elements for gripping a reel, arranged on the gripper sensor device with sensors, an evaluation and control device that receives signals from the sensor device and processed, and a positioning device, of the evaluation and Control device is driven and moves the gripper with the sensor device via a Bobinenkern, wherein the evaluation and control device is designed to determine from the signals received from the sensor device a Bobinenkernmitte B, wherein the Bobinenhandhabungsvorrichtung is characterized in that the sensors spatially separated are arranged one another in sensor group modules, wherein exactly two sensor group modules are each provided with four sensors, wherein the sensor group modules are arranged around the elements for gripping the bobbin that when crossing a bobbin core of signal change n the sensors of at least one sensor group module location coordinates of four points on a circle with respect to a plane that is parallel to the end face of the reel, can be determined. As a result, the detection or gripping of a bobbin can take place automatically.

It proves to be an advantage of the reel handling device according to the invention that a sensor group module is used for distance measurement, which supplies usable signals for the position determination of a reel during the movement of the gripper.

In a preferred embodiment of the reel handling apparatus, the sensor group modules are identical

By an identical design of the sensor group modules it is possible to carry out a uniform and thus simplified evaluation of the signals.

The elements for gripping the reel are in particular designed as clamping jaws, which are arranged rotationally symmetrical and are moved in the radial direction.

In this way, a cylindrical cylindrical bobbin in its outer dimensions can be particularly easily detected by the clamping jaws are moved either from the outside against the outer cylindrical surface of the reel or from the inside against the inner cylindrical surface of the reel and thereby moved so far in that the clamped bobbin can be lifted in this way.

The object is also achieved by a machine of the tobacco processing industry comprising a reel handling apparatus according to the invention.

• der Greifer erfasst die Bobine, eine Auswerte- und Steuereinrichtung legt eine vorläufige Bobinenkernmitte fest und der Greifer gibt die Bobine wieder frei,
• ein Sensor wird über den Bobinenkern entlang einer Linie, die durch die vorläufige Bobinenkernmitte führt, bewegt, und es werden die Signaländerungen des Sensors aufgezeichnet,
• die Auswerte- und Steuereinrichtung ermittelt aus den Signaländerungen für den Sensor eine zugehörige Bobinenkernmitte B_s durch Bestimmung der Mitte der Verbindungsstrecke zwischen den beiden Stellen, an denen Signaländerungen auftreten, und ermittelt daraus einen dem Sensor zugeordneten Offset O_s zwischen der für den Sensor ermittelten Bobinenkernmitte B_s und der zuvor festgelegten vorläufigen Bobinenkernmitte,

wobei das Verfahren für eine zweite Linie wiederholt wird, die im Wesentlichen senkrecht zur ersten Linie verläuft, so dass für den Sensor zwei Offsets O_Sx, O_Sy in zwei im Wesentlichen senkrecht zueinander verlaufenden, durch die beiden Linien bestimmten Richtungen ermittelt werden.Furthermore, the object is achieved by a method for operating a reel handling device, in particular the tobacco processing industry, comprising a gripper for gripping a reel and a sensor device with sensor group modules arranged on the gripper, wherein sensors of the sensor group modules are calibrated with the following steps:

• the gripper grasps the bobbin, an evaluation and control device sets a provisional bobbin center and the gripper releases the bobbins,
• a sensor is moved over the bobbin core along a line passing through the tentative bobbin core center, and it the signal changes of the sensor are recorded,
• the evaluation and control device determines from the signal changes for the sensor an associated Bobinenkernmitte B _s by determining the center of the link between the two locations where signal changes occur, and determines therefrom a sensor associated offset O _s between the determined for the sensor Bobinenkernmitte B _s and the preliminarily specified bobbin center,

wherein the method is repeated for a second line substantially perpendicular to the first line so that two offsets O _Sx , O _{Sy are determined} for the sensor in two substantially mutually perpendicular directions determined by the two lines.

In this way, a calibration of the sensors is possible, for each individual sensor is determined which Bobinenkernitte B _s results from its signal changes, preferably by determining the middle of the link between the two locations where signal changes occur. This bobsleigh core B _s is compared with a tentatively considered bobbin core center. In later measurements for determining the bobbin core center B _s , it is then possible to include this offset O _{s of} a sensor from the outset in the evaluation of its signal changes. Thus, it is possible to obtain a substantially complete information about the deviation behavior of a sensor with respect to a plane which runs parallel to the end face of the reel.

In a preferred embodiment of the method, the Sensor moved back and forth along the line or moved several times, so that the signal changes in question are multiple, and the sensor is an associated Bobinenkernmitte B _{s determined} from the average values of the respective signal changes.

It proves particularly useful to carry out the method steps described for at least two sensors, in particular for all sensors.

• der Greifer wird durch eine Positionierungsvorrichtung so verfahren, dass die Sensorgruppenmodule den verlängert gedachten Bobinenkern umgeben,
• mindestens ein Sensorgruppenmodul fährt über den Bobinenkern,
• die Signaländerungen des mindestens einen Sensorgruppenmoduls werden an eine Auswerte- und Steuereinrichtung weitergeleitet,
• die Auswerte- und Steuereinrichtung bestimmt aus den Signaländerungen von vier Sensoren des mindestens einen Sensorgruppenmoduls eine Bobinenkernmitte B,

indem den Signaländerungen Ortskoordinaten von insbesondere vier Punkten auf einem Kreis in Bezug auf eine Ebene, die parallel zur Stirnfläche der Bobine verläuft, zugeordnet werden, zu jeweils zwei Punkten eine Geradengleichung für deren Mittelsenkrechte formuliert und schließlich der Bobinenkernmittelpunkt B als Lösung der beiden Geradengleichungen, d.h. als Schnittpunkt der beiden Mittelsenkrechten, bestimmt wird.The object is also achieved by a method for operating a reel handling apparatus, in particular the tobacco processing industry, which comprises a gripper for gripping a reel and a sensor device arranged on the gripper with sensor group modules. The process is characterized by the following steps:

• the gripper is moved by a positioning device so that the sensor group modules surround the extended imaginary bobbin core,
• at least one sensor group module moves over the bobbin core,
• the signal changes of the at least one sensor group module are forwarded to an evaluation and control device,
• the evaluation and control device determines from the signal changes of four sensors of the at least one sensor group module a bobbin center B,

by the signal changes spatial coordinates of particular four points on a circle with respect to a plane that runs parallel to the end face of the bobbin, be formulated in each case two points a straight line equation for the bisectors and finally the bobbin center B as a solution of the two straight line equations, ie as an intersection of the two perpendicular bisector, is determined.

With this method, it is possible in a particularly simple and precise manner to determine a Bobinenkernmitte B, which later allows precise control of the gripper for detecting the reel.

If the bobbin is difficult to access, e.g. is applied to a laterally delimiting wall, it is possible by the arrangement of different sensor group modules to a gripper to select a sensor group module so that when moving the gripper drive the sensors of the respective sensor group module on the bobbin core.

If, in a preferred embodiment of the method, the at least one sensor group module is moved back and forth along the line or moved several times, it is possible to determine a bobbin center B from the mean values of the multiple signal changes.

In an expedient embodiment of the method, the gripper subsequently grasps the bobbin as a function of the specific bobbin center B.

In particular, it is advantageous to the methods for operating a Bobinenhandhabungsvorrichtung in such a way that first the deviations of the sensors are determined and then a Bobinenkernmitte B is determined on the basis of these deviations.

In particular, the offsets O _S or O _Sx, O _Sy determined for the sensors are taken into account in the determination of a bobbin center B.

The particular advantage of the invention described here is that the sensors of a reel handling device are calibrated without the need for their own calibration tools.

The signal changes in the distance measuring sensors are generally due to the fact that a sensor immediately measures a greater distance when entering the area of a bobbin core, because it no longer only measures the distance to the end face of the bobbin. Conversely, a signal change occurs when a sensor emerges from the bobbin core, because then the shortened distance is measured up to the end face of the bobbin. Instead of a distance measurement, brightness values can also be measured.

Fig. 1

eine schematische perspektivische Ansicht auf einen Greifer mit einer Sensoreinrichtung, der mit einer Auswerte- und Steuereinrichtung sowie mit einer Positionierungsvorrichtung verbunden ist;

Fig. 2a, 2b, 2c

drei schematische Darstellungen der Stirnfläche einer Bobine sowie des Bobinenkerns, über die ein Sensorgruppenmodul mit vier Sensoren geführt wird;

Fig. 3

eine schematische Ansicht auf einen Ausschnitt eines Bobinenkerns;

Fig. 4

eine schematische Ansicht auf einen Bobinenkern sowie auf ein Sensorgruppenmodul mit vier Sensoren, das über den Bobinenkern geführt wird;

Fig. 5

eine schematische Ansicht einer Stirnseite einer Bobine sowie den Bobinenkern mit zwei Sensorgruppenmodulen;

Fig. 6

eine weitere schematische Ansicht einer Stirnseite einer Bobine sowie den Bobinenkern mit zwei Sensorgruppenmodulen;

Fig. 7

eine Darstellung eines Kreises, für den durch Errichtung von Mittelsenkrechten zu Randpunkten des Kreises ein Mittelpunkt bestimmt wird.

The invention will now be described by way of example without limitation of the general inventive concept by means of embodiments with reference to the accompanying schematic drawings, with respect to the disclosure of all in the. Text unspecified details of the invention is expressly referenced. Show it:

Fig. 1

a schematic perspective view a gripper with a sensor device, which is connected to an evaluation and control device and with a positioning device;

Fig. 2a, 2b, 2c

three schematic representations of the end face of a reel and the Bobinenkerns over which a sensor group module with four sensors is guided;

Fig. 3

a schematic view of a section of a Bobinenkerns;

Fig. 4

a schematic view of a bobbin core and on a sensor group module with four sensors, which is guided over the Bobinenkern;

Fig. 5

a schematic view of a front side of a reel and the Bobinenkern with two sensor group modules;

Fig. 6

a further schematic view of a front side of a reel and the Bobinenkern with two sensor group modules;

Fig. 7

a representation of a circle for which a midpoint is determined by establishing bisectors to edge points of the circle.

In the following figures, the same or similar elements or corresponding parts are provided with the same reference numerals, so apart from a corresponding renewed idea and only deviations of the embodiments shown in these figures will be explained with respect to the first embodiment.

In the FIG. 1 is a schematic perspective view of a gripper 1 with a sensor device 2 shown. The sensor device 2 is connected to an evaluation and control device 9 and to a positioning device 10. The gripper 1 is designed for detecting a reel, not shown, which is removed, for example, from a pallet and placed on an unwinding device. The gripper 1 has three trained as jaws elements 3, 4 and 5, which in a in the FIG. 1 bobbin core 7 not shown are introduced and spread there to capture the bobbin. For this purpose, it is necessary that the gripper 1 is positioned over the bobbin so that the jaws 3, 4 and 5 can be inserted into the bobbin core 7. A comparatively constructed gripper 1 is for example made EP-A-1 157 952 known. Around the clamping jaws 3, 4 and 5, two sensor group modules 2A and 2B are arranged. The sensor group modules 2A and 2B are identical and each have four sensors 11-14 and 21-24. The sensors 11 - 14, 21 - 24 are sensors for distance measurement.

The Figures 2a, 2b and 2c are three schematic representations of the end face of a reel and the bobbin core 7, via which a sensor group module 2A with four sensors 11 - 14 is guided. The representations represent the time sequence which results from the movement of the sensor group module 2A via the bobbin core 7. This is a calibration process, in which the sensor 11 is guided in the direction of the arrow over the bobbin core 7 along the dashed line. In FIG. 2a is the sensor 11 not yet in the area of Bobinenkern 7, in the FIG. 2b the sensor 11 has just entered the area of the Bobinenkerns 7, so that a signal change is recorded, and in the Figure 2c the sensor 11 is returned to the dashed line again, so that a further signal change on the sensor 11 is recorded.

The FIG. 3 11 shows a schematic view onto a section of a bobbin core 7 and in particular illustrates that varying ΔY of lines I ₁ and I ₂ through a preliminary bobbin center in the Y direction has only a small effect on the signal change ΔX in the X direction. As a result, if there is an inaccuracy in the choice of the preliminary bobbin center, reliable signal changes are still recorded when a sensor 11-14, 21-24 is guided along a line I ₁ or I ₂ through the preliminary bobbin center.

FIG. 4 is a schematic view of a bobbin core 7 and a sensor group module 2A with four sensors 11- 14, which is guided over the bobbin core 7. The positions 1, 2, 3 and 4 correspond in each case to a position of the sensor group module 2A, the sensors 11-14 being guided in succession along a line through the preliminary bobbin core center.

In the FIG. 5 is a schematic view of a front side of a reel and a bobbin core 7 with two sensor group modules 2A and 2B shown. The gripper 1, not shown here, is moved so that the sensor group modules 2A, 2B surround the extended imaginary bobbin core 7. For this purpose, an envelope 8 of the possible positions of the Bobinenkerns 7 is given, which is a limit for the sensors 11 - 14, 21 - 24, in such a way that the sensors 11 - 14, 21 - 24 always outside the Bobbins need to lie 7 before determining a tentative bobbin core center. In the FIG. 5 is also a gripper center 6 of a gripper 1, not shown, which serves as a default for the provisional Bobinenkernmitte example.

The FIG. 6 shows a further schematic view of a front side of a reel and a Bobinenkerns 7 with two sensor group modules 2A and 2B, wherein the condition that all the sensors 11 - 14, 21 - 24 are outside the bobbin core 7, just barely fulfilled.

In the FIG. 7 a circle is shown for which a midpoint is determined by establishing mid-perpendiculars g and h. The circle corresponds to the bobbin core 7, the points SP1, SP2, SP3 and SP4 respectively correspond to the points at which signal changes of one of the sensors 11-14, 21-24 are recorded. For the points SP1 and SP3, the center perpendicular g is constructed, and for the points SP2 and SP4, the perpendicular bisector h is constructed. The intersection of the two mid-perpendiculars g and h defines a bobbin center B. The coordinates of the point of intersection and thus of the bobbin center B can thus be determined with simple mathematical methods.

LIST OF REFERENCE NUMBERS

1

grab

2

sensor device

2A

Sensor group module

2 B

Sensor group module

Third

Element for gripping a bobbin

4

Element for gripping a bobbin

5

Element for gripping a bobbin

6

Center of the gripper

7

reel core

8th

Envelope of the allowed positions of the bobbin core

9

Evaluation and control device

10

positioning device

11

Sensor for distance measurement

12

Sensor for distance measurement

13

Sensor for distance measurement

14

Sensor for distance measurement

21

Sensor for distance measurement

22

Sensor for distance measurement

23

Sensor for distance measurement

24

Sensor for distance measurement

Claims (12)

1. Bobbin handling apparatus, in particular of the tobacco processing industry, comprising a gripper (1) having elements (3, 4, 5) for gripping a bobbin, a sensor device (2) disposed on the gripper (1) and having sensors (11 - 14, 21 - 24), an evaluation- and control device (9) that receives and processes signals from the sensor device (2), and a positioning apparatus (10) that is controlled by the evaluation-and control device (9) and moves the gripper (1) with the sensor device (2) over a bobbin core, wherein the evaluation- and control device (9) is designed to detect a bobbin core centre B from the signals received by the sensor device (2), characterized in that the sensors (11 - 14, 21 - 24) are disposed spatially separate from one another in sensor group modules (2A, 2B), wherein precisely two sensor module groups (2A, 2B) each comprising four sensors (11 - 14, 21 - 24) are provided, wherein the sensor group modules (2A, 2B) are arranged in such a way around the elements (3, 4, 5) for gripping the bobbin that during travel over a bobbin core from signal changes of the sensors (11 - 14, 21 - 24) of at least one sensor group module (2A, 2B) position coordinates of four points on a circle are determinable in relation to a plane extending parallel to the end face of the bobbin.
2. Bobbin handling apparatus according to claim 1, characterized in that the sensor group modules (2A, 2B) are identical in construction.
3. Bobbin handling apparatus according to claim 1 or 2, characterized in that the elements (3, 4, 5) for gripping the bobbin takes the form of clamping jaws, which are arranged in a rotationally symmetrical manner and moved in particular in radial direction.
4. Machine of the tobacco processing industry having a bobbin handling apparatus according to one of claims 1 to 3.
5. Method of operating a bobbin handling apparatus, in particular of the tobacco processing industry, comprising a gripper (1) for gripping a bobbin and a sensor device (2) disposed on the gripper (1) and having sensor group modules (2A, 2B), wherein sensors (11 - 14, 21 - 24) of the sensor group modules (2A, 2B) are calibrated using the Following steps:

   - the gripper (1) grasps the bobbin, an evaluation-and control device (9) defines a provisional bobbin core centre and the gripper (1) releases the bobbin,

   - a sensor (11 - 14, 21 - 24) is moved over the bobbin core (7) along a line running through the provisional bobbin core centre and the signal changes of the sensor (11 - 14, 21 - 24) are recorded,

   - the evaluation- and control device (9) detects from the signal changes for the sensor (11 - 14, 21 - 24) an associated bobbin core centre B_S by determining the centre of the connecting path between the two points, at which signal changes arise, and determines therefrom an offset O_S between the bobbin core centre B_S established for the sensor (11 - 14, 21 - 24) and the previously defined provisional bobbin core centre that is associated with the sensor (11 - 14, 21 - 24),

   wherein the method is repeated for a second line that runs substantially at right angles to the first line, so that for the sensor (11 - 14, 21 - 24) two offsets O_Sx, O_Sy are determined in two directions, which extend substantially at right angles to one another and are determined by the two lines.
6. Method according to claim 5, characterized in that the sensor (11 - 14, 21 - 24) is moved forward and back or a plurality of times along the line, so that there are multiple signal changes and for the sensor (11 - 14, 21 - 24) an associated bobbin core centre B_S is determined from the mean values of the respective signal changes.
7. Method according to claim 5 or 6, characterized in that the method steps are carried out for at least two sensors (11 - 14, 21 - 24).
8. Method of operating a bobbin handling apparatus, in particular of the tobacco processing industry, comprising a gripper (1) for gripping a bobbin and a sensor device (2) disposed on the gripper (1) and having two sensor group modules (2A, 2B),
   characterized by the following steps:

   - the gripper (1) is moved by a positioning apparatus (10) in such a way that the sensor group modules (2A, 2B) surround an imaginary extension of the bobbin core (7),

   - at least one sensor group module (2A, 2B) travels over the bobbin core (7),

   - the signal changes of the at least one sensor group module (2A, 2B) are transmitted to an evaluation- and control device (9),

   - the evaluation- and control device (9) from the signal changes of four sensors (11 - 14, 21 - 24) of the at least one sensor group module (2A, 2B) determines a bobbin core centre B,

   - by associating with the signal changes position coordinates of in particular four points on a circle in relation to a plane extending parallel to the end face of the bobbin, by formulating at in each case two points a line equation for the mean perpendicular thereof, and finally by determining the bobbin core centre B as a solution of the two line equations, i.e. as a point of intersection of the two mean perpendiculars.
9. Method according to claim 8, characterized in that the at least one sensor group module (2A, 2B) is moved forward and back or a plurality of times along the line, so that there are multiple signal changes and a bobbin core centre B is determined from the mean values of the signal changes.
10. Method according to claim 8 or 9, characterized in that the gripper (1) grasps the bobbin in dependence upon the determined bobbin core centre B.
11. Method according to one of claims 8 to 10, characterized in that a method according to one of claims 5 to 7 precedes.
12. Method according to claim 11, characterized in that the offsets O_S or O_Sx, O_Sy determined for the sensors are taken into account when determining a bobbin core centre B.

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