JPH06147832A - Method and apparatus for detecting dimensions at level difference part - Google Patents

Abstract

PURPOSE:To allow highly accurate stabilized noncontact detection of dimensions at a level difference part without requiring labor. CONSTITUTION:Level difference parts 101, 102, 104, 105 are irradiated with light L having high directivity across high position sides 103b, 103c, 106b, 106c and low position sides 103a, 106a thereof. Lights R1 reflected on the low position sides 103a, 106a and lights R2, R3 reflected on the high position sides 103b, 103c, 106b, 106c are received in such directions as allowing discrimination of mutual positional shift due to level difference. Dimensions at the level difference parts 101, 102, 104, 105, are detected based on the images thus obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for contactlessly detecting a step size.

For example, a carton 10 shown in (1) of FIG.
0 is assembled from a corrugated cardboard blank B having a developed shape shown in (2) of FIG. 7. The blank B includes side surface portions 100a that form the front, rear, left, and right side surfaces of the carton 100, and four upper surface portions 100b that form the upper surface of the carton 100 and that are partitioned from each other in correspondence with the front, rear, left, and right side surfaces.
100c, 100d, 100e and four lower surface parts 100f, 100g, 100 which constitute the lower surface of the carton 100 and are partitioned from each other corresponding to the front, rear, left and right side surfaces.
It has h and 100i and an adhesion margin 100j, and is bent along a fold line indicated by a dashed line in the figure. The adhesion fee 100
j is provided so as to be continuous with one end of the side surface portion 100a and is bonded to the inner surface of the other end of the side surface portion 100a with an adhesive. At the time of storage or transportation, the blank B is flatly folded as shown in (1) of FIG. 6 after the bonding margin 100j is pasted to save space.

In the blank B as described above, if the bonding position of the bonding margin 100j with respect to the side surface portion 100a is deviated, the assembled carton 100 is distorted and the predetermined contents cannot be packed. Therefore, before the blank B is assembled, it is inspected whether or not the bonding margin 100j is accurately bonded.

That is, in the blank B folded flat as shown in (1) of FIG.
The two upper surface portions 100b and 100e which are close to each other are superposed on the other upper surface portion 100c and are opposed to each other with a space therebetween. Thereby, as shown in (2) of FIG. 6, a step portion 101 based on the thickness of the corrugated board is formed by the one upper surface portion 100b close to the bonding margin 100j and the other upper surface portion 100c, and The step portion 102 based on the thickness of the corrugated board is formed by the other upper surface portion 100e close to the bonding margin 100j and the other upper surface portion 100c.
1 and 102 form a groove 103 having a constant width W1. Similarly, two lower surface portions 100f and 100i close to the adhesion margin 100j and another lower surface portion 100g.
A pair of step portions 104 and 105 are formed by and the step portions 104 and 105 form a groove 106 having a constant width W2. Whether widths W1 and W2 of the grooves 103 and 106 are within a predetermined constant value can determine whether or not the bonding margin 100j is accurately bonded.

[0005]

PRIOR ART AND PROBLEM TO BE SOLVED BY THE INVENTION Conventionally, the width dimensions W1 and W of the groove formed by the stepped portion as described above.
The measurement of 2 was performed manually using a caliper or the like.
Therefore, there are individual differences in the measured values depending on the measurer, and a great deal of labor is required to inspect all of the large amount of blanks B, so only the sampling inspection is performed, and the inspection accuracy is low.

It is an object of the present invention to provide a step size measuring method and a step size detecting apparatus which can solve the above-mentioned problems of the prior art.

[0007]

A feature of the method of the present invention is that light having a directivity is irradiated over the high side and the low side of the step, and the reflected light and the low light on the high side are irradiated. The point is that each reflected light is imaged from a direction in which the mutual positional deviation based on the step with the reflected light on the local side can be discriminated, and the dimension of the stepped portion is detected from the image. The light having the directivity is preferably slit light.

The device of the present invention is characterized by a light source capable of radiating light having directivity over the high side and the low side of the step, and the reflected light on the high side and the low side. The point is that an image pickup means capable of picking up each reflected light from a direction capable of discriminating a positional deviation from each other based on the step difference with the reflected light and a calculation means capable of calculating the dimension of the stepped portion from the image. The light having the directivity is preferably slit light.

[0009]

When the directional light is applied to both the high side and the low side of the stepped portion, the reflected light on the high side and the reflected light on the low side are displaced from each other based on the step. Occurs. Therefore, the position data of the reflected light at the step portion is obtained from the image obtained by capturing the reflected light from the direction in which the positional deviation can be discriminated. The size of the step can be obtained from the position data. For example, the depth of the step can be obtained from the difference between the position data of the reflected light on the high side and the position data of the reflected light on the low side. Further, when the groove is constituted by a pair of step portions, light having directivity is radiated over the low side and the high side, and the reflected light at the low side and the high side The position data of the reflected light at one step portion and the position data of the reflected light at the other step portion are obtained by imaging each reflected light from a direction in which the mutual positional deviation based on the step with the reflected light can be determined. be able to. From the difference between the two position data, the facing distance between the two step portions, that is, the width dimension of the groove can be obtained. In addition, when the convex portion is formed by the pair of step portions, light having directivity is irradiated over the high side and the low side, and the reflected light on the high side and the low side. By capturing each reflected light from a direction in which a positional deviation between the reflected light and the reflected light can be discriminated from each other, the position data of the reflected light at one step and the position data of the reflected light at the other step can be obtained. can get. From the difference between the two position data, the width dimension on the high side can be obtained. By using the light having the directivity as the slit light, it is possible to clarify the positional deviation between the reflected light on the high place side and the reflected light on the low place side based on the step.

[0010]

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

FIG. 1 shows a line for inspecting the width dimensions W1 and W2 of the pair of grooves 103 and 106 formed by the step portions 101, 102, 104 and 105 in the carton blank B. This inspection line includes a conveyor 2 that conveys the blank B in the horizontal direction (Z direction) indicated by an arrow in the figure, and a light source 3 that irradiates the blank B conveyed by the conveyor 2 with light having directivity from above. Is equipped with. The blank B is placed on the conveyor 2 such that the width directions of the grooves 103 and 106 are along the horizontal direction (X direction) orthogonal to the transport direction. The light source 3 emits the laser slit light L, and the longitudinal direction of the slit light L is along the X direction. Further, the light source 3 is provided on the lower side 103 of each step 101, 102, 104, 105.
a, 106a and a pair of high-sides 103b, 103c, 10
6b and 106c are fixed to a position where the slit light L can be radiated via fixing means (not shown). The width of the slit light L is preferably about 0.5 mm to 5 mm.

In order to detect the front end of the blank B conveyed by the conveyor 2 in the conveying direction, a pair of sensors 4, 5 are used.
Are fixed to the side of the conveyor 2 via fixing means outside the drawing. The front end of the blank B in the carrying direction is provided with one groove 103.
Is detected by the first sensor 4 when it reaches the position illuminated by the slit light L, and is detected by the second sensor 5 when the other groove 106 reaches the position illuminated by the slit light L.

Low side 103a, 10 of the slit light L
6a reflected light R1 and a pair of high places 103b, 1
03c, 106b, 106c reflected light R2, R3
A CCD camera 6 is fixed above the conveyer 2 via a fixing means (not shown) for picking up images of and. That camera 6
Is arranged in front of the position where each groove 103, 106 is irradiated by the slit light L, and each reflected light R1, R2, R
Image 3 from diagonally above. Thereby, each step portion 10
Each reflected light R based on the step difference of 1, 102, 104, 105
The reflected lights R1, R2, and R3 are imaged from the directions in which the mutual positional deviations of 1, R2, and R3 can be determined.

The camera 6 is connected to the image processing device 7. The image processing apparatus 7 is composed of a computer having an input / output interface 8, a central processing unit 9 and an image memory 10. The image memory 10
Stores the image data composed of the grayscale signal of 256 gradations. The display device 1 is attached to the image processing device 7.
1 and the control device 12 are connected. The display device 11 monitors the image captured by the camera 6. The control device 12 has an input / output interface 1
3, a computer having a central processing unit 14 and a storage unit 15. In this control device 12,
The sensors 4 and 5, the keyboard type input device 16,
A floppy disk type external storage device 17 and a display device 18 are connected.

The control procedure by the control program stored in the storage device 15 of the control device 12 will be described with reference to the flowchart shown in FIG.

First, a control start signal is input from the keyboard type input device 16 (step 1).

Next, the mask image data is sent from the external storage device 17 to the image processing device 7 via the control device 12.
It is stored in the image memory 10 (step 2). The mask image data divides the image processing area in the image memory 10 as shown by hatching in FIG. 4A, so that the image density of the area outside the image processing area is set to a predetermined value or less in advance.

Next, it is judged whether or not a control end signal is input from the keyboard type input device 16 (step 3). If the end signal is input, the control is ended. 1 The signal waiting state from the sensor 4 is entered (step 4).

Next, when the front end of the blank B in the conveying direction is detected by the first sensor 4, the image processing device 7 sends a trigger signal to the camera 6 to perform an instant image pickup, and the image signal is sent to the image processing device 7. The image is stored in the image memory 10 (step 5). As a result, as shown by hatching in FIG. 4B, the step portion 10 that constitutes one groove 103 is formed.
The image data of the reflected lights R1, R2, and R3 at 1 and 102 are obtained.

Next, the state of waiting for a signal from the second sensor 5 is set (step 6).

Next, when the front end of the blank B in the transport direction is detected by the second sensor 5, the image processing device 7 sends a trigger signal to the camera 6 to perform an instant image pickup, and the image signal is sent to the image processing device 7. The image is stored in the image memory 10 (step 7). As a result, as shown by hatching in FIG. 4B, the step portion 10 that constitutes the other groove 106 is formed.
Image data of the reflected lights R1, R2, and R3 at 4 and 105 are obtained.

Next, the image processing device 7 is caused to calculate the width dimension W1 of the one groove 103 and the width dimension W2 of the other groove 106 (steps 8 and 9), and the calculation result is stored in the external storage device 17.
And store it on the display device 18 (steps 10 and 11). Then, the process returns to step 3 and the above procedure is repeated.

Each groove 103, 1 by the image processing device 7
The calculation procedure of the width dimensions W1 and W2 of 06 will be described with reference to the flowchart shown in FIG.

First, masking is performed to remove image data outside the image processing area from the image data captured by the camera 6 and stored in the image memory 10 (step 1). As a result, only the image data in the image processing area is left as shown in (3) of FIG.

Next, in the image processing area, the image data composed of the grayscale signals of 256 gradations is binarized by a preset constant threshold value (step 2). As a result, as shown in (4) of FIG.
Binary image data in which the image of 2 and R3 is bright and the other portions are dark is obtained.

Next, in the binarized image data, labeling for recognizing the image of each reflected light R1, R2, R3 is performed (step 3).

Next, as shown in (5) of FIG. 4, the image located at the bottom of the labeled images, that is, the low side 103a, 106 of each groove 103, 106.
An image of the reflected light R1 at a is extracted (step 4).

Next, the X-coordinate (X1) at one end and the X-coordinate (X2) at the other end of the extracted image are obtained with reference to the preset origin. The X coordinate (X1) at one end corresponds to the position where the reflected lights R1, R2 are displaced in the one step portion 101, 104, and the X coordinate (X2) at the other end is the other step portion 102, 105. Reflected light R1, R3 at
Corresponds to the position where the displacement occurs. Next, the distance between the X coordinate (X1) at one end and the X coordinate (X2) at the other end is obtained (step 5). Stepped portion 10 whose distance is opposite to each other
Spacing of 1, 102, 104, 105, that is, groove 10
The width dimensions W1 and W2 are 3, 106. FIG. 5 shows the results of measuring 400 blanks B by the above inspection line. In the figure, the solid line indicates the width W1 of one groove 103, the broken line indicates the width W2 of the other groove 106, and the dashed line indicates the difference between the two groove widths. The relationship between the measured dimension of (W1-W2) and the frequency is shown.

According to the above structure, the groove 10 of the blank B is
Since it is possible to measure the width dimensions W1 and W2 of 3, 106 without contact by hand and with a constant accuracy, it is necessary to determine whether or not the bonding margin 100j of the large number of blanks B is accurately bonded. All can be inspected without.

The present invention is not limited to the above embodiment. For example, in the above-mentioned embodiment, the groove 10 is selected from the images of the respective reflected reflected lights R1, R2, R3.
As shown in FIG. 8, not only the image of the reflected light R1 on the low side 103a and 106a of the high side 103
b, 103c, 106b, 106c reflected light R
Images of 2 and R3 are also extracted, and the vertical direction of each image (Y direction)
The coordinates (Y1), (Y2), (Y3), and (Y4) of the image are calculated to obtain the distances (Y3-Y1) (Y4-Y2) between adjacent images.
That is, the depth dimension of the step portions 101, 102, 104, 105 may be obtained.

Further, in the above embodiment, the dimension of a pair of step portions facing each other constituting the groove is detected, but the depth dimension of a single step portion is detected, or the convex portion is formed as shown in FIG. Width dimension W and height dimension H on the high side of the pair of stepped portions
10 may be detected, or the width dimensions W ′, W ″ and the depth dimension D at a plurality of step portions forming continuous irregularities may be detected as shown in FIG. The side or the low side may be a curved surface, and the laser slit light is used as the light having directivity, but the light is not particularly limited, and slit light such as white slit light may be used. , In the above-mentioned embodiment, the slit light is irradiated simultaneously over the high-side and the low-side of the stepped portion, but by integrating the time-series images by the spot light, the present invention can be obtained similarly to the case by the slit light. The present invention is not limited to the inspection of the bonded portion of the bonding margin 100j of the blank B, and can be widely used for detecting the dimension of the step portion.

[0032]

According to the present invention, it is possible to detect the size of the step portion in a non-contact, stable manner and without labor.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a configuration of a dimension detection device according to an embodiment of the present invention.

FIG. 2 is a flowchart of an embodiment of the present invention.

FIG. 3 is a flowchart of an embodiment of the present invention.

FIG. 4 is an explanatory diagram of an image according to an embodiment of the present invention.

FIG. 5 is a diagram showing data of measurement results of an example of the present invention.

FIG. 6 is an explanatory diagram of a blank according to an embodiment of the present invention.

FIG. 7 is an explanatory view of a carton according to an embodiment of the present invention.

FIG. 8 is an explanatory diagram of an image of a modified example of the present invention.

FIG. 9 is an explanatory diagram of a step according to a modified example of the present invention.

FIG. 10 is an explanatory diagram of a step according to a modified example of the present invention.

[Explanation of symbols]

 3 light source 6 camera 7 image processing device 12 control device 101, 102, 104, 105 step portion 103a, 106a low side 103b, 103b, 106c, 106c high side L slit light R1, R2, R3 reflected light

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[Procedure amendment]

[Submission date] November 17, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Change

[Correction content]

[Reference Numerals] 3 light sources 6 camera 7 the image processing apparatus 12 the control device 101, 102, 104, 105 stepped portion 103a, 106a low-income side 103b, 103 c, 106 b, 106c altitude side L slit light R1, R2, R3 reflected light

Claims (4)

[Claims] 1. A misalignment of the reflected light on the high side and the reflected light on the low side with respect to each other by irradiating light having directivity over the high side and the low side of the step. A method for detecting the size of a step portion, which is characterized in that each reflected light is imaged from a direction in which can be determined, and the size of the step portion is detected from the image. 2. The step size detecting method according to claim 1, wherein the light having directivity is slit light. 3. A light source capable of irradiating light having directivity over the high side and the low side of the stepped portion, and the reflected light on the high side and the reflected light on the low side are mutually based on the step. An apparatus for detecting a size of a step portion, comprising: an image pickup means capable of taking an image of each reflected light from a direction capable of discriminating the positional deviation of the position difference; and a calculation means capable of calculating the size of the step portion from the image. 4. The step size detecting device according to claim 3, wherein the directional light is slit light.