JP2000318719A - Labeling equipment - Google Patents

Abstract

(57) [Problem] To automatically and accurately apply a label to a conveyed work even when a supplied label itself is misaligned. SOLUTION: A work W conveyed by a conveyor 10 is provided.
In a labeling apparatus for measuring the amount of displacement based on a work image obtained by capturing a label L, a label holding pad 32 for holding a label L supplied to a receiving stand 26, and a label held by the pad 32 being imaged. A second camera 40 for inputting an image, a second image processing apparatus for measuring the amount of displacement of the label L based on the label image, and the pad 32 moved to a sticking place and conveyed to the sticking place Label attaching device 1 for attaching label L to work W
And a correcting means for correcting the label sticking position in consideration of not only the amount of positional shift of the work but also the amount of positional shift of the label when the label is applied by the device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a labeling device,
In particular, the present invention relates to a labeling apparatus suitable for application when a label is automatically attached to a predetermined position of a conveyed work.

[0002]

2. Description of the Related Art Conventionally, in a labeling device, a label supplied from a label supply device is sucked and held by a label holding pad on a work sequentially conveyed by a transfer device such as a belt conveyor, and the label is automatically attached. That is being done.

As a label to be automatically applied by such a labeling apparatus, there is a label which is automatically read in a later step, for example, a label on which a bar code is printed. It is extremely important that the tape is accurately attached to a predetermined position.

Therefore, in the conventional labeling apparatus, the conveyed work is tracked, the image is taken by a camera, and the obtained image is subjected to image processing. In the width direction, the amount of misalignment such as the inclination angle with respect to the flow direction is measured, and the label affixing position by the label holding pad is corrected so that the measured amount of misalignment is eliminated. Was.

[0005]

However, the positional shift amount of the workpiece conveyed as described above is measured by image processing, and the position where the label is stuck by the holding pad is determined so as to eliminate the positional shift amount. The conventional labeling device for correction has a problem in that the label is not always supplied to a fixed position, so that the label may not be accurately attached to a target position on the work.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. Even when a label supplied to a predetermined position is misaligned, the label is always transferred to a work to be conveyed. An object of the present invention is to provide a labeling device that can accurately and automatically attach a labeling device.

[0007]

According to the present invention, in a labeling apparatus, a first image pickup means for picking up an image of a work conveyed by a conveying means and inputting a work image, and a work image of the work based on the input work image. First image processing means for measuring the amount of displacement, label holding means for holding a label supplied at a predetermined position, and second imaging means for picking up a label held by the label holding means and inputting a label image Second image processing means for measuring the amount of displacement of the label based on the input label image, and moving the label holding means to a sticking place, and holding the workpiece conveyed to the sticking place. Label applying means for applying a label which has been applied, and when the label is applied by the label applying means, the positional deviation amount of the label in addition to the measured positional deviation amount of the work. By providing a correction means for correcting the attaching position of the label by the label holding means be considered is obtained by solving the above problems.

That is, according to the present invention, when a label is adhered by measuring the positional deviation amount of a work by image processing and correcting the position to be adhered by the label affixing means so that the positional deviation amount is eliminated. The amount of misalignment occurring in the label itself is also measured, and the sticking position can be corrected in consideration of this. Even if the position shifts after the operation, the label can be automatically applied to an accurate position with high accuracy.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic plan view showing a labeling device according to an embodiment of the present invention, FIG. 2 is a schematic front view showing an enlarged main part thereof, and FIG. 3 is a schematic diagram showing a control system of the labeling device. FIG.

As shown in FIG. 1, the labeling apparatus according to the present embodiment comprises a conveyor (transporting means) 10 for transporting a work W in the direction of an arrow, and an encoder 12 for outputting a pulse signal corresponding to the amount of movement of the conveyor 10. And a work detection sensor 14 which detects the leading end of the work W conveyed by the conveyer 10 and forms a tracking means together with the encoder 12 and an edge (side end) along the conveyance direction of the work W and its vicinity. A first camera (first imaging means) 16 for photographing and inputting a work image, a label sticking device 18 for sticking a label L to a predetermined position of a work W based on the input work image, and a label attached to the device 18 And a label supply device 20 for supplying the same.

The label supply device 20 intermittently adheres to the backing sheet P while unwinding the continuous backing sheet P wound around the label coil 22, as shown in an enlarged view of the main part in FIG. By pulling out the printed label, the printing unit 24 that prints on the label, and the printed label L are fed rightward in the figure, and the feed direction of the mount P is changed at an acute angle, so that the label is removed from the mount P. A small-diameter roll 28 for peeling off the label L and transferring the label L to the label receiving table 26, and a backing coil 30 for winding the backing sheet P from which the label L has been peeled off are provided. The label receiving base 26 has been subjected to a surface treatment so that the label L coated with the adhesive does not adhere thereto, and the transferred label L is stopped by a stopper 26A.

The sticking device 18 is provided with the label receiving table 2.
6, a label holding pad 32 that holds the label L transferred by vacuum suction, an air cylinder 34 that moves the holding pad 32 up and down, and a θ-axis drive that rotates the holding pad 32 about a vertical direction. Guide 36 in the X direction, where the holding pad 32 and the holding pad 32 are in the width direction of the conveyor 10.
And an X-axis drive unit 38 that moves along 8A. Then, the label holding pad 32 at the position shown in FIG. 2 is lowered by the air cylinder 34 and then raised after holding the label L on the label receiving base 26, and then the holding pad 32 is moved to the X-axis driving section 38. Is moved to a sticking place on the conveyor 10, and is lowered again to stick the label L to the work W at the place. After that, the label holding pad 32 performs the reverse operation, and the label
6, the work W
Is automatically affixed to the label L.

In the labeling apparatus of the present embodiment, when the holding pad 32 is lowered to hold the label L from the label receiving base 26, the label L is raised and moved to the sticking place by the X-axis drive unit 38. And a second camera (second imaging means) 40 for imaging the label L held on the holding pad 32 at a predetermined position and inputting a label image.

In this embodiment, as shown in FIG. 3, a first image processing apparatus (computer) for processing a work image picked up by the first camera 16 and measuring a position shift amount of the work as shown in a control system thereof. ) 42 and the second camera 4
And a second image processing device (computer) 44 for performing image processing on the label image captured by the image sensor 0 to measure the amount of displacement of the label. Encoder 1
Sequencer (correction means) 46 together with the pulse signal from 2
To be entered.

The sequencer 46 calculates the X-direction movement amount and the θ-axis rotation amount (movement amount) of the label holding pad 32 based on the information and outputs the calculated amount to the servo motor drivers 48A and 48B. Accordingly, the X-axis drive unit 38 moves the holding pad 32 to the corrected position according to a command from the driver 48A, and the θ-axis drive unit 36 moves the holding pad 32 to the corrected angle according to a command from the driver 48B. Adjust to On the other hand, a flow direction (transport direction, Y direction) calculated (tracked) by a pulse signal from the encoder 12 counted after the tip of the work W is detected by the work detection sensor 14.
When the amount of movement in the direction (direction) reaches the target value, the solenoid valve 50 is driven to lower the holding pad 32, the position of which has been corrected by the air cylinder 34, so that a label is attached to an accurate position. Control is performed.

The first embodiment will be described in detail.
In the image processing device 42, in order to attach a label L to the work W conveyed by the belt conveyor 10, the first camera 16 captures an image of the work W, and the work W is captured based on the input work image. Image processing for obtaining the width direction position and inclination is performed. At this time, the position of the work W to which an image is input is calculated by the sequencer 46 as a position in the flow direction based on an encoder pulse output from the time when the leading end is detected by the work detection sensor 14.

FIG. 4 shows the features of image processing performed by the first image processing device 42. First, an input image (not shown) is smoothed to remove noise, and then a predetermined threshold is set. Then, a work image (binary image) as shown in FIG. Next, the work image (A) is differentiated to create a differential image schematically shown in FIG. 8B from which edges are extracted, and a reference X set in advance for the differential image is set. A shift in the X direction (width direction) is calculated from a shift between the coordinates and the extracted edge E. At this time, the shift amount between the edge E on the two Y reference lines A and B parallel to the X direction and the reference X coordinate is calculated, and the difference in the shift amounts between the two reference lines A and B is calculated in the Y direction (flow direction). )
Is calculated. This makes it possible to measure the amount of displacement of the work W itself on the conveyor 10 (the amount of displacement in the X direction and the inclination with respect to the Y direction).

On the other hand, in the second image processing device 44, after the label L placed on the label receiving table 26 is suction-held by the holding pad 32 of the sticking device 18, the holding pad 32 is raised, After being moved to a predetermined position above the second camera 40 (always the same position) and stopped,
The image processing is performed on the label image input by the camera 40, and the displacement amount of the label L is measured.

FIG. 5 shows the characteristics of the measurement method using the image processing. FIG. 7A shows a case where the label image is normal in the X and Y directions without any shift (left in the figure) and a case where there is a shift (right in the figure). A label image (not shown) input by the second camera 40 is subjected to noise removal in the same manner as in the case of FIG. The center of gravity of the white region corresponding to the label L is calculated for the valued image, and the difference is calculated from the center of gravity of the normal region. Here, the normal position means a position where the center of the visual field of the second camera coincides with the center of the rotation axis of the holding pad. Further, the inclination angle generated on the label L is shown in FIG.
As shown in (B), the binary image of FIG. (A) is differentiated to create a differential image from which the edge of the label is extracted.
Find the intersection of the preset straight lines A and B with the edge,
It is calculated from the difference between the Y coordinate values at both intersections.

As described above, in this embodiment, the work W
When the label L is applied to the workpiece W, the workpiece W is tracked to measure the position in the flow direction, the position where the label is applied is image-measured, and the position where the label is applied (width direction, flow direction, Angle),
Position of label L to be actually put (width direction, flow direction, angle)
Was measured in the same manner, and further correction was performed based on the result. Therefore, when the label L is transferred to the label receiving tray 26, the label may be tilted,
6, the label L held by the holding pad 32 is misaligned because the label L is not completely placed on the label 6 or the label L itself is shifted in the width direction. Thus, the label L can be attached.

Next, the operation of the present embodiment will be specifically described with reference to an example in which a management barcode label L (100 × 10 mm) is attached to a work W made of a resin sheet (500 × 500 mm).

The position where the label L is applied is within an error range of ± 0.5 mm from the edge (side end) in the width direction of the resin sheet and ± 1.0 mm from the edge (tip) in the flow direction. Thus, in order to keep the deviation in the width direction within ± 0.5 mm, the inclination of the label L having a length of 100 mm needs to be within about 0.6 °.

As described above, the conveyor 10 is provided with the encoder (resolution: 0.02 mm / pulse), and the work detection sensor (photoelectric sensor) 14, which is a sensor for locating the transferred work W, is turned on. From this point, pulse signals corresponding to a predetermined distance to the first camera 16 are counted. When the counting of the pulse signals for the predetermined distance is completed, a trigger is applied to the first image processing device 42 at that time, the first camera 16 captures an image of the resin sheet W, and a work image is input. The position and inclination of the work are calculated by the same method as shown in FIG.

On the other hand, when a bar code is printed by the printing unit (printer) 24 on the label L drawn out from the label coil 22 in the label supply device 20, the label L is moved downstream, and Cradle 2
Handed over to 6. When the label L is transferred to the receiving table 26 in this way, the label holding pad 32 immediately descends to suck and hold the label L, rise to a predetermined height, and then move in the X direction to move the second camera 40. Is temporarily stopped at a predetermined position above, and the camera 40 takes an image of the label L.

When the label L is imaged as described above, the second image processing device 44 processes the obtained label image by the same method as that shown in FIG. Calculate (measure) the amount and angle. Next, in the sequencer 46, the first image processing device 4
The movement amount and angle in the width direction of the work W input from the second image processing device 44 are corrected by the movement amount and angle in the width direction of the label L input from the second image processing device 44. At that time, the attaching device 1
The count number of the pulse signal from the encoder 12 corresponding to the moving distance of the label L to the sticking position of the label L by 8 is corrected based on the shift amount in the flow direction measured by the second image processing device 44.

The above correction values are commanded from the sequencer 46 to the X-axis and θ-axis actuators (drive units) 38 and 36 via the servo motor drivers 48A and 48B, whereby the label is applied to the resin sheet W. L can be stuck with high accuracy. Therefore, according to the present embodiment, the barcode label L can be stuck to the target sticking position of the work W with high accuracy, so that even when a narrow barcode is automatically read, the barcode label L is reliably read. It becomes possible.

Although the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof.

For example, in the above embodiment, a resin sheet is printed as a specific example of a work, and a bar code is printed as a specific example of a label. However, it is needless to say that the present invention is not limited to this.

Although the position of the work in the flow direction is measured by tracking, the position at which the flow direction can be specified, such as the front end of the work, is simultaneously input as an image and measured by image processing. Is also good.

[0031]

As described above, according to the present invention,
Even if a label supplied to a predetermined position is misaligned, the label can always be automatically and accurately attached to a conveyed work.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a labeling device according to an embodiment of the present invention.

FIG. 2 is a schematic front view showing an enlarged main part of the labeling device.

FIG. 3 is a block diagram schematically showing a control system of the labeling device.

FIG. 4 is an explanatory view showing the principle of measuring an image of a positional shift amount of a work.

FIG. 5 is an explanatory diagram showing the principle of measuring the amount of displacement of a label by image.

[Description of Signs] 10 ... Conveyor 12 ... Encoder 14 ... Work detection sensor 16 ... First camera 18 ... Sticking device 20 ... Label supply device 22 ... Label coil 24 ... Printing unit 26 ... Label receiving stand 28 ... Small diameter roll 30 ... Backboard Coil 32 ... Label holding pad 34 ... Air cylinder 36 ... Theta axis drive unit 38 ... X axis drive unit 40 ... Second camera 42 ... First image processing unit 44 ... Second image processing unit 46 ... Sequencer 48 ... Servo motor driver 50 …solenoid valve

Claims (3)

[Claims] A first image pickup means for picking up an image of a work conveyed by a conveying means and inputting a work image; a first image processing means for measuring a displacement amount of the work based on the input work image; Label holding means for holding a label supplied at a predetermined position; second image pickup means for picking up a label held by the label holding means and inputting a label image; and the label based on the input label image A second image processing means for measuring the amount of misalignment of, a label sticking means for moving the label holding means to the sticking place, and for sticking the held label to the work carried to the sticking place, When applying a label by the label affixing means, the label holding means applies the label in consideration of the amount of misalignment of the label in addition to the measured amount of misalignment of the work. Position labeling apparatus characterized by comprising a correction means for correcting. 2. The apparatus according to claim 1, wherein said second image processing means calculates a position of a center of gravity of a label area in said input label image, and calculates a position of said work in a direction of conveyance of said work and a direction orthogonal thereto. Calculating a displacement amount, extracting an edge of the label region, calculating an intersection between the edge and two preset reference straight lines, and calculating an inclination angle from the both intersections. Labeling equipment. 3. The labeling apparatus according to claim 1, further comprising tracking means for tracking a work conveyed by the conveyance means and measuring a position of the work in the conveyance direction.