JP2000337818A - Dimension inspecting apparatus and dimension inspecting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a measurement error by enabling a dimension inspecting apparatus to correct a measurement line with precision finer than one picture element when inspection can be performed always to the same measurement position of each molded object, by correcting a measurement line for recognizing the edge position of an object to be inspected. SOLUTION: Position deviation amount ΔP of a rain gutter A to a reference position Pm is previously detected. A first edge position at a position where the number of picture elements of an integer part α of the amount ΔP is corrected from the reference position Lm of a measurement line, and a second edge position at a position where the number of picture elements of the integer part α to which one picture element is added is corrected from the reference position Lm are obtained. A coordinate point obtained by an edge position calculating formula [first edge position coordinate + (second edge position coordinate - first edge position coordinate)×(decimal part of position deviation amount)] is made a true edge position, and the dimension of the rain gutter is recognized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dimensional inspection apparatus and a dimensional inspection method for inspecting dimensions of a molded product such as a gutter formed by extrusion or the like. In particular, the present invention relates to an improvement of a pass / fail determination operation for determining whether or not a dimension of a molded article to be inspected is a predetermined dimension based on image data captured by an imaging unit such as a CCD camera.

[0002]

2. Description of the Related Art Conventionally, the outer diameter and the thickness of a molded article formed by extrusion molding or the like have been inspected using image data captured by a CCD camera. This inspection is applied to, for example, a case where the cross-sectional shape of a rain gutter formed by extrusion molding is determined to be acceptable.

[0003] The principle of this inspection will be described below.
In this inspection, for example, a rain gutter having a cross-sectional shape shown in FIG. Then, in advance, the Y-axis direction on the drawing (vertical direction in FIG. 1)
Are set, and the edge positions Pa and Pb of the rain gutter on the measurement line L are detected. Thereafter, the height dimension of the rain gutter in the Y-axis direction is detected by calculating the distance between the edges Pa and Pb. Also, the inspection is performed in the same manner when inspecting the width dimension of the rain gutter in the X-axis direction (the horizontal direction in FIG. 1). That is,
A virtual measurement line (not shown) orthogonal to the measurement line L is set, the edge position of the rain gutter on this measurement line is detected, and the distance between the edges is calculated.

As a technique for detecting the positions of the edges Pa and Pb, image data captured by a CCD camera is binarized to separate pixels on the end face of the gutter from pixels on the background. Thereafter, the boundary between the end face of the rain gutter and the background on the measurement line L is regarded as edges Pa and Pb. Further, as disclosed in Japanese Patent Application Laid-Open No. 3-261803, a primary differentiation process is performed on the image data on the measurement line, and the peak value is detected as an edge position.

[0005] By the way, when inspecting a plurality of molded products, in order to perform an accurate dimensional inspection for each of them,
It is necessary to eliminate the measurement error by inspecting the same measurement position on each molded product. As one method for that,
The position of the measurement line L is always set to a position having a predetermined dimension from one edge of the molded product, and the positions of the edges Pa and Pb on the measurement line L are detected. Specifically, the following method is adopted. As shown in FIG. 1, a position correction window W is provided on image data captured by a CCD camera, and a reference line Pm is set in the position correction window W. Then, the contour of the molded product included in the position correction window W (FIG. 1)
, The average position of the left edge S1) in the X-axis direction is detected,
The shift amount in the X-axis direction between the average position S1 and the reference line Pm is recognized, and the shift amount is calculated as a position correction amount ΔP. Then, the corrected measurement line L is set on the molded product by shifting the reference position Lm of the measurement line temporarily set in advance in the X-axis direction by the position correction amount ΔP (the molding line shown in FIG. Since the shift direction of the product is rightward, the correction direction of the measurement line is also rightward). Accordingly, the distance C (the reference position Pm within the position correction window W) is always set in the X-axis direction from the left edge position of the molded product.
The measurement line L is set at a position separated by the distance between the measurement line L and the reference position Lm of the measurement line). Then, the upper and lower sides S of the molded product on the measurement line L after this correction
2, the positions of the edges Pa and Pb of S3 are detected, and the distance between the edges Pa and Pb is calculated. Thereby, in the inspection operation of each molded article, Y
The distance between the edges Pa and Pb on the measurement line L extending in the axial direction is obtained, and the dimension of the molded product in the Y-axis direction is recognized.

On the other hand, when recognizing the dimension of a molded product in the X-axis direction, a similar operation is performed to correct the measurement line extending in the X-axis direction, and the edge position on the measurement line after this correction is detected. Calculate the distance between edges.

[0007]

However, since the above-described correction of the measurement line is performed on image data (digital data) captured by a CCD camera, the correction dimension can be performed only in units of one pixel. Can not. Therefore, accurate position correction may not be performed.

More specifically, although the position correction amount ΔP can be calculated with an accuracy of one pixel or less by using the method disclosed in the above-mentioned publication, the correction position on the image data is determined on a pixel-by-pixel basis. Can only be set in. That is, with reference to FIG. 2 showing pixel data (binarized for each pixel) near one edge Pa, X
If the integer part of the position correction amount ΔP in the axial direction is α and the decimal part is β, if the position is to be corrected in the X-axis direction by ΔP from the reference position Lm of the measurement line, the position of the measurement line L after the correction Should be the position of Lt in the figure considering the decimal part. However, on digital images, 1
Since the correction amount can be set only in pixel units,
Actually, α from the reference position Lm of the measurement line in the X-axis direction
The position L1 corrected only in the X-axis direction or (α + 1)
The position of the corrected measurement line L can be set only in any of the corrected positions L2. Specifically, when the position correction amount ΔP is 3.2 (α = 3, β = 0.2) (the measurement line L is set at a position corrected by 3.2 pixels from the reference position Lm of the measurement line). However, in practice, the corrected measurement line L can only be set at the position L1 corrected by three pixels from the reference position Lm or at the position L2 corrected by four pixels.

As a result, when inspecting a plurality of molded products, an edge position is detected at a position corrected by α from the reference position Lm to calculate an inter-edge distance or a reference position Lm. In this case, an edge position is detected at a position corrected by (α + 1) from the above to calculate an inter-edge distance. Then, when the edge position P1 at the position corrected by α and the edge position P2 at the position corrected by (α + 1) are shifted (when the positions in the Y-axis direction are different), at most this P1 A measurement error will occur by the difference between the position of P2 and the position of P2 (e1 + e2 in FIG. 2). In this case, accurate dimensional inspection may not be performed, and in some cases, dimensional defects may be overlooked, or dimensional defects may be determined even though dimensional defects have not occurred. May occur.

The present invention has been made in view of the above points, and an object of the present invention is to correct a measurement line for recognizing an edge position of an object to be inspected so that each molded product is corrected. In contrast to the case where the inspection can always be performed at the same measurement position, the measurement line can be corrected with an accuracy of one pixel or less, thereby eliminating measurement errors.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, as shown in FIG. 2, an edge at a position L1 corrected by α from a reference position Lm of the measurement line is provided. The position P1 and the edge position P2 at the position L2 corrected by (α + 1) from the reference position Lm of the measurement line are obtained. And the true edge position P
t is assumed to be located between the two edge positions P1 and P2, and the decimal part β of the position correction amount ΔP and the two edge positions P1 and P2
2 to determine the true edge position Pt.

-Solution Means- First, as shown in FIGS. 1 to 3, the first solution means adopted by the present invention is to judge the quality of the inspection object A by recognizing the dimensions of the inspection object A. It is assumed that a dimensional inspection device that makes a determination is used. This dimension inspection apparatus is provided with an imaging unit 63, a measurement unit 66, a measurement line setting unit 67, an edge position calculation unit 68, and a pass / fail determination unit 69. Imaging means 6
Reference numeral 3 denotes an image of a predetermined area of the inspection object A. The measuring unit 66 detects the position of the specific location S1 in the predetermined area of the inspection object A from the digitized image data obtained by the imaging of the imaging unit 63,
The reference position Pm of the specific position set in advance is compared with the actual specific position S1, and the amount of positional deviation ΔP between the two is converted into the number of pixels consisting of an integer part α and a decimal part β and measured. Is what you do. The measurement line setting means 67
Receiving the pixel quantity data from the measuring means 66, the integer part α of the displacement amount ΔP with respect to the reference position Lm of the measurement line set in advance at a position having a predetermined dimension C from the reference position Pm of the specific location is described. The first correction measurement line L1 is set at the position corrected by the number of pixels, and the position is obtained by adding one pixel to the number of pixels of the integer part α of the displacement ΔP with respect to the reference position Lm of the measurement line. The second correction measurement line L2 is set at the corrected position. The edge position calculating means 68 sets the edge position of the inspection target A on the first correction measurement line L1 as the first edge position P1,
The edge position of the inspection target A on the correction measurement line L2 is defined as the second edge position P2, and the edge position is calculated by the following equation: the first edge position coordinate + (the second edge position coordinate−the first edge position coordinate) × the decimal number of the displacement amount The coordinate point obtained by the section is calculated as a true edge position Pt, and the true edge position Pt is obtained for a plurality of locations on the inspection object A. Pass / fail judgment means 69
Receiving the output of the edge position calculation means 68, the true edge positions P at a plurality of locations calculated by the edge position calculation means 68
The size of the inspection object A is recognized based on t, and the quality of the inspection object is determined.

According to this specific matter, the first edge position P on the first corrected measurement line L1 whose position has been corrected from the reference position Lm of the measurement line by the number of pixels of the integer part α of the displacement ΔP.
1 and a second edge position P2 on the second corrected measurement line L2 obtained by adding one pixel to the number of pixels of the integer part α of the displacement amount ΔP from the reference position Lm of the measurement line and correcting the position. True edge position Pt can be obtained.
That is, by reflecting the value of the decimal part β of the positional deviation amount ΔP in the detection of the edge position, the true edge position Pt can be obtained with an accuracy of one pixel or less. Thereby, when inspecting a plurality of inspection objects, it is possible to inspect each inspection object at the same measurement position with high accuracy of one pixel or less, and eliminate measurement errors. it can.

[0014] The second solution is to optimize image data when the inspection object is imaged by the imaging means. That is, in the first solving means, when the imaging means captures an image of a predetermined area of the inspection object, the inspection object is irradiated with light from a direction substantially orthogonal to the imaging direction of the imaging means. Irradiation means is provided.

According to this specific matter, an image is taken by the imaging means in a state where the light from the irradiation means is applied to the surface of the inspection object. For this reason, image data of the imaging unit is obtained in a state where the contrast between the end surface of the inspection object facing the imaging unit and the background of the inspection object is emphasized. Therefore, it is possible to obtain image data in which the contour of the inspection object is clear, and the detection accuracy of the required edge position is improved. As a result, the true edge position can be obtained with higher accuracy.

The third solution specifically specifies a dimension inspection portion of the inspection object. That is, the first
Alternatively, in the second solving means, the inspection object is a cylindrical body having a substantially square cross section. The predetermined region of the inspection object is an end face on one end side in the extension direction of the cylindrical body. Further, the specific portion of the inspection object is an outer edge portion of one side of the end face.
Then, the first edge position of the inspection object is defined as an intersection between the outer edge of the inspection object side extending in a direction perpendicular to the one side and the first correction measurement line, and the second edge position of the inspection object is determined by the inspection. This is the intersection between the outer edge of the target side and the second correction measurement line.

According to this specific matter, the dimension inspection apparatus can be used as an apparatus for inspecting a shape by recognizing an edge position of a side on an end face of an inspection object.

A fourth solution is a dimension inspection method for recognizing the dimensions of the inspection object to determine the quality of the inspection object. This dimension inspection method is performed by a measurement step, a measurement line setting step, an edge position calculation step, and a pass / fail judgment step. In the measurement step, after a predetermined area of the inspection target is imaged by the imaging means to obtain digitized image data and a position of the specific location of the inspection target within the predetermined area is detected, a predetermined identification The reference position of the position and the actual position of the specific position are compared, and the amount of displacement between the two is converted into the number of pixels consisting of an integer part and a decimal part and measured. In the measurement line setting step, after the measurement step, the reference position of the predetermined position is located at a predetermined distance from the reference position of the specific location. A first correction measurement line is set at the corrected position, and the number of pixels of the integer part of the displacement amount with respect to the reference position of the measurement line is set to 1
A second correction measurement line is set at a position where the position is corrected by adding pixels. In the edge position calculation step, the edge position of the inspection object on the first correction measurement line is defined as a first edge position, and the edge position of the inspection object on the second correction measurement line is defined as a second edge position. The coordinate point obtained by the first edge position coordinate + (second edge position coordinate−first edge position coordinate) × decimal part of the displacement amount is calculated as a true edge position, and this true edge position is calculated for the inspection object. Ask for multiple locations. The pass / fail judgment step is performed after the edge position calculation step, and the pass / fail judgment of the test object is performed by recognizing the dimensions of the test object based on the calculated true edge positions at a plurality of places.

According to this specific matter, it is possible to determine the true edge position with an accuracy of one pixel or less, as in the case of the above-described first solving means, and when inspecting a plurality of inspection objects. In addition, it is possible to perform inspection on the same measurement position with high accuracy of 1 pixel or less for each inspection object,
Measurement errors can be eliminated.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, a case will be described in which the present invention is applied to a dimension inspection of a cross-sectional shape of a resin rain gutter manufactured by extrusion as an inspection target.

Before describing the shape inspection, a production line and a production process of a resin gutter will be described.

FIG. 4 is a schematic diagram showing the rain gutter production line 1. In this production line 1, an extruder 2, a forming die 3, a take-up machine 4, a cutting machine 5, and an inspection device 6 which is a characteristic part of the present embodiment are provided with an extrusion die 21 from an upstream side to a downstream side of the production line. is set up.

The extrusion die 21 has a cavity that matches the cross-sectional shape of the rain gutter A. The rain gutter A is cylindrical, and has a closed cross section in which four corners of a square are slightly curved inward, as shown in FIG. When inspecting whether or not the cross-sectional shape of the rain gutter A is accurately formed, the distance between the outer edges of the opposing sides (see FIG. 6)
Is inspected by the inspection device 6 to determine whether or not the dimension T) is within a predetermined range. The normal dimensions of each part of the gutter A produced by the gutter production line 1 according to the present embodiment are 80 mm in width and 4000 mm in height, and 4000 mm in length. The control width of the dimension in the vertical direction is set to ± 0.5 mm. That is,
If the width or height does not fall within the management width, the rain gutter A is determined to be defective.

The forming die 3 is constituted by, for example, a cooling tank in which cooling water is stored, and cools and solidifies the rain gutter intermediate molded product A ′ extruded from the extruder 2.

The take-up machine 4 includes a pair of upper and lower belt driving devices 4.
The belt drive devices 41, 42 are arranged such that they flow downstream of the production line 1 with the rain gutter intermediate molded product A 'interposed therebetween.

The cutting machine 5 is for cutting the rain gutter intermediate molded product A 'which is continuously extruded and formed into predetermined dimensions.

FIG. 5 shows a downstream end portion of the gutter production line 1 (the production line after the cutting machine 5).
5A is a plan view thereof, and FIG. 5B is a side view thereof.
Between the cutting machine 5 and the inspection device 6, there is provided a conveyor 7 for conveying the rain gutter A cut by the cutting machine 5 onto the inspection table 61 of the inspection device 6. The conveyor 7 increases the flow speed of the rain gutter A discharged from the cutting machine 5 through the production line 1 and transports the rain gutter A onto the inspection table 61.
For example, while the line speed up to the cutting machine 5 is 4 m / min, the conveyor 7 conveys the gutter A onto the inspection table 61 at 8 m / min. As a result, the time from when the rain gutter A is transported onto the inspection table 61 to when the next rain gutter A is discharged from the cutting machine 5 and transported onto the inspection table 61 is secured. The inspection by the inspection device 6 is performed first. Specifically, the inspection time by the inspection device 6 is, for example, 0.5
sec.

In the production process of the rain gutter A in the production line 1, first, a resin material is extruded from the extruder 2, and the resin material passes through a cavity of the extrusion die 21. At this time, the resin material is continuously extruded as a rain gutter intermediate molded product A ′ having a predetermined sectional shape corresponding to the cavity. This extruded gutter intermediate molded product A '
Is cooled and solidified in the forming die 3.
Thereafter, the rain gutter intermediate molded product A ′ is sandwiched between the pair of upper and lower belts 43 and 44 of the take-off machine 4 and sent to the downstream side of the production line 1. The cutting machine 5 measures the feed amount of the rain gutter intermediate molded product A ′, and cuts the intermediate molded product A ′ at every predetermined feed amount. As a result, a rain gutter A having a predetermined length is produced. The transport speed of the rain gutter A thus produced is increased by the conveyor 7 and transported onto the inspection table 61 of the inspection device 6. The inspection operation in the inspection device 6 will be described later.

The above is an outline of the production line and production process of the resin gutter A. Next, an inspection device 6 for inspecting the shape of the produced gutter A and the dimension inspection operation of the gutter A by the inspection device 6 will be described.

-Description of Inspection Device 6- As shown in FIG. 5, the inspection device 6 has a stopper 61a and a guide plate 61b standing on the inspection table 61. The stopper 61a contacts the end face of the rain gutter A conveyed from the conveyor 7, and receives the rain gutter A. The guide plate 61b contacts the side surface of the gutter A extending in the longitudinal direction to position the gutter A on the inspection table 61.

As shown in FIG. 7, the inspection device 6 includes a high-frequency fluorescent lamp 62 as an irradiating means and an imaging means 2 as an imaging means used for inspecting the cross-sectional shape of the rain gutter A.
A three-dimensional CCD camera 63 is provided. High frequency fluorescent lamp 62
Is annular, and the rain gutter A passes through the inner space. That is, by irradiating the rain gutter A with light from the outer peripheral side by the high-frequency fluorescent lamp 62, the contrast between the end face of the rain gutter A and its background becomes clear. As a result, image data in which the contour of the end face of the rain gutter A is clear can be obtained, and the accuracy of the dimensional inspection can be improved.

The CCD camera 63 is disposed, for example, built in the stopper 61a so as to face the end face of the rain gutter A (a predetermined area of the inspection object in the present invention). The background can be imaged. The field of view of this CCD camera is 100 mm, and the resolution is 0.2 mm.

Further, the present inspection device 6 is provided with the inspected rain gutter A
Is provided with a transfer machine 8 for transferring the sheet to the carts 81 and 82 (see FIG. 5). The transporter 8 transports the rain gutter A to the non-defective carriage 81 when the rain gutter A is determined to be non-defective, and to the defective carriage 82 when the defective gutter A is determined to be defective. A suction unit 83 for vacuum-suctioning the upper surface of the gutter A,
83 are provided.

Further, as shown in FIG.
Is provided with a controller 64 for processing image data from the CCD camera 63. This controller 6
4 includes an A / D converter 65, a measuring unit 66, a measuring line setting unit 67, an edge position calculating unit 68, and a pass / fail determination unit 69.

The A / D converter 65 converts an image picked up by the CCD camera 63 from analog data to digital data.

The measuring means 66 receives the digital image data from the A / D converter 65 and provides a position correction window W on the image data as shown in FIG. (A reference position of a specific portion in the present invention). Then, an average position in the X-axis direction of the contour of the rain gutter A (the left edge S1 in FIG. 1) included in the position correction window W (a specific portion of the inspection object in the present invention) is detected. The shift amount in the X-axis direction between S1 and the reference line Pm is recognized, and the shift amount is calculated as the position correction amount ΔP. The position correction amount ΔP is obtained by converting the position shift amount into a pixel quantity including an integer part α and a decimal part β.

The measuring line setting means 67 receives the pixel quantity data from the measuring means 66, and as shown in FIGS. 1 and 2, a measuring line set at a position having a predetermined dimension C from the reference line Pm. The first correction measurement line L1 is set at a position corrected by the number of pixels of the integer part α of the position correction amount ΔP with respect to the reference position Lm of the line, and the position correction is performed with respect to the reference position Lm of the measurement line. Quantity Δ
A second correction measurement line L2 is set at a position where the position is corrected by adding (α + 1) one pixel to the number of pixels of the integer part α of P.

The edge position calculating means 68 is shown in FIG.
As shown in the enlarged view of the lower side S2 (inspection target side) in the vicinity of the edge detection unit (around the Pa point in FIG. 1 and binarized for each pixel), the first correction measurement is performed as shown in FIG. Line L1
The upper edge position is defined as a first edge position P1 (coordinate point on the Y axis in the figure), and the edge position of L2 on the second correction measurement line is defined as a second edge position P2 (coordinate point on the Y axis in the figure). age,
A value obtained by the following edge position calculation formula is calculated as a true edge position Pt.

Pt = P1 + (P2−P1) × β (1) In this case, the position shift amount is in the “positive” direction (rightward direction in the figure).
Is described. Position shift amount is "negative"
(The left direction in the figure), the integer part α and the decimal part β both have “negative” values. Further, the edge position calculating means 68 similarly calculates the true edge position for the upper side S3 (side to be inspected) of the rain gutter A.

Specifically, in the present embodiment, the outer dimensions of the rain gutter A on the center line of the rain gutter A are inspected. Therefore, in order to make the corrected measurement line L coincide with the center line of the rain gutter A, the reference position Lm of the measurement line is set at a position 40 mm from the reference line Pm in the position correction window W (the width dimension of the rain gutter A). (Half the position of 80 mm). Since the resolution of the CCD camera is 0.2 mm, the reference position Lm of the measurement line can be set at this position by shifting by 200 pixels in the X-axis direction.

The pass / fail judgment means 68 receives the output of the edge position calculation means 67, and performs inspection based on a plurality of true edge positions calculated by the edge position calculation means 67 using the above-described edge position calculation formula. This is to judge the quality of the inspection object by recognizing the size of the object.
Specifically, the upper and lower sides (inspection target sides) S of the end face of the rain gutter A
2, true edge positions Pa and Pb are calculated for S3,
The height of the rain gutter A is recognized by calculating the distance between the two, and the quality is determined based on whether or not the height is within the management width.

-Description of Inspection Operation- Next, the dimension inspection operation of the rain gutter A using the inspection device 6 will be described with reference to the flowchart of FIG. In the inspection operation of the rain gutter A, inspection is performed for each of the height dimension and the width dimension of the rain gutter A. Since the operations of the two inspections are different only in the direction to be inspected, a case where the height dimension is inspected will be described as a representative here.

The inspection operation includes a measuring step of the displacement amount by the measuring means 66, a measuring line setting step by the measuring line setting means 67, an edge position calculating step by the edge position calculating means 68, and rain by the pass / fail judgment means 69. The pass / fail judgment process of the gutter A is sequentially performed.

First, the rain gutter A cut by the cutting machine 5 in step ST1 of FIG. 8 is conveyed to the inspection table 61 of the inspection device 6 by the conveyor 7 in step ST2. The rain gutter A transported onto the inspection table 61 is positioned at a predetermined position on the inspection table 61 by contacting the stopper 61a and the guide plate 61b (step ST3).

Thereafter, steps ST4 to ST6
Move to the step of measuring the amount of displacement. In this measurement step, first, the analog image data captured by the CCD camera 63 is converted into digital data by the A / D converter 65, and this digital image data is
(Step ST4). Thereafter, a position correction window W is provided on the image data, and a reference line Pm is set in the position correction window W (step ST).
5). Then, in step ST6, the average position in the X-axis direction of the contour of the rain gutter A (the left edge S1 in FIG. 1) included in the position correction window W is detected, and the average position between the average position S1 and the reference line Pm is detected. The amount of deviation between them is recognized, and this amount of deviation is calculated as the position correction amount ΔP.

After this displacement measuring step, step S
Move on to the measurement line setting step of T7. In this step, as described above, the reference position Lm of the measurement line set in advance is set.
And the reference position Lm of the measurement line when the position is corrected by the number of pixels of the integer part α of the displacement amount, and the reference position Lm of the measurement line by one pixel in the number of pixels of the integer part α of the displacement amount A second correction measurement line L2 when the position is corrected by adding (α + 1) is set. That is, each of the correction measurement lines L1 and L2 obtained by correcting the reference position Lm with two correction amounts of “α” and “α + 1” is set.

Thereafter, the process proceeds to the edge position calculation step of step ST8. In this step, the first set as described above is set.
The intersection between the corrected measurement line L1 and the outer edge of the lower side S2 of the gutter A is defined as a first edge position P1, and the intersection of the second corrected measurement line L2 and the outer edge of the lower side S2 of the gutter A is set. As the second edge position P2, and the value obtained by the above-described edge position calculation formula is calculated as the true edge position Pt.

More specifically, for example, each edge P1, P2
Are P1 = 300, P2 = 301 and the position correction amount ΔP is “3.2 (α = 3, β = 0.2), these values are substituted into the edge position calculation formula. Then, Pt = 300 + (301-300) × 0.2 Pt = 300.2, and the Y-axis coordinate “300.2” of the true edge position Pt is obtained.
Can be requested.

The same operation is performed on the upper side S3 of the rain gutter A, and the true edge position Pb of the side S3 is calculated in the same manner.

Thereafter, steps ST9 to ST1
The process proceeds to the second pass / fail judgment step. In this step, first, each of the upper and lower sides S2, obtained in the above-described edge position calculation step,
The distance between the true edge positions in S3 is calculated (step ST9). Thereafter, in step ST10, whether the distance between edges falls within a predetermined range (± the management width ±
0.5 mm). here,
If the distance between the edges is within the predetermined range, it is determined to be a good product, and the process proceeds to step ST11, where the rain gutter A is transferred to the good product carrier 81 by the transporter 8. Conversely, if the distance between edges is not within the predetermined range, it is determined that the product is defective, and the process proceeds to step ST12, where the rain gutter A is transferred to the defective product cart 82 by the transporter 8.

Such a dimension inspection operation of the rain gutter A is continuously performed on the rain gutter A discharged from the cutting machine 5.

When inspecting the width of the rain gutter A,
The measurement line is set in the horizontal direction, and the position correction window W is set on one of the upper and lower sides of the rain gutter A.

As described above, in the present embodiment, the edge position P1 on the first correction measurement line L1 corrected by α from the reference position Lm of the measurement line in the position correction window W, and the position of the measurement line An edge position P2 on the second correction measurement line L2 corrected by (α + 1) from the reference position Lm is obtained, and a true edge position Pt existing between the two edge positions P1 and P2 is calculated as a decimal part of the position correction amount ΔP. We are seeking using β. Therefore, the true edge position Pt can be obtained with an accuracy of one pixel or less. As a result, when inspecting a plurality of gutters A, each gutter A can be inspected at the same measurement position with high accuracy of one pixel or less, and measurement errors can be eliminated. As a result, the reliability of the dimensional inspection can be improved.

-Other Embodiments- In the above-described embodiments, the case where the present invention is applied to the dimensional inspection of the resin gutter A is described. The present invention is not limited to this, and can be applied to inspection of products of various shapes such as a tubular body and a plate-like body.

In the above embodiment, the CCD camera 6
3, the controller 64 converts the analog image data picked up by the controller 3 into digital image data. The present invention is not limited to this, and a digital camera may be employed as the imaging means. According to this, the controller 64
The A / D converter 65 becomes unnecessary inside the controller 64.
Can be simplified.

Further, in this embodiment, the outer dimensions of the inspection object are inspected. The present invention is not limited to this, and can be applied to a device for inspecting a thickness dimension or the like of an inspection object. Inspection of this thickness dimension can be performed by detecting an edge position between an outer edge and an inner edge of one side of the inspection object.

[0057]

As described above, according to the present invention, the following effects are exhibited.

In the dimension inspection apparatus according to the first aspect and the dimension inspection method according to the fourth aspect, each inspection object is corrected by correcting a measurement line for recognizing an edge position of the inspection object. For an object that can always be inspected at the same measurement position, the amount of displacement of the inspection object with respect to the reference position is detected in advance, and an integer of the amount of displacement from the reference position of the measurement line. The first edge position at the position corrected by the number of pixels of the part and the second edge position at the position corrected by adding one pixel to the number of pixels of the integer part of the displacement amount from the reference position of the measurement line Ask for each. Then, the true edge position is calculated based on the decimal part of the displacement and both edge positions.
Therefore, a true edge position can be obtained with an accuracy of one pixel or less. As a result, when inspecting a plurality of inspection objects, each inspection object can be inspected at the same measurement position with high accuracy of one pixel or less,
Measurement errors can be eliminated, and the reliability of dimensional inspection can be improved.

According to the second aspect of the present invention, the irradiating means for irradiating the inspection object with light from a direction substantially perpendicular to the imaging direction of the imaging means is provided. For this reason, it is possible to obtain image data of the imaging unit in a state where the contrast between the end surface of the inspection object facing the imaging unit and the background of the inspection object is emphasized. Therefore, it is possible to obtain image data in which the outline of the inspection object is clear, and it is possible to improve the detection accuracy of the required edge position, whereby it is possible to obtain the true edge position with higher accuracy. Will be possible. As a result, it is possible to further enhance the reliability of the dimensional inspection device.

According to the third aspect of the present invention, the shape inspection is performed on the end face of the inspection object formed by the cylindrical body. For this reason, the use form of the dimension inspection apparatus according to the first aspect of the present invention can be embodied, and the practicality of the present apparatus can be enhanced.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a correction operation of a measurement line.

FIG. 2 is a diagram for explaining the principle of the present invention.

FIG. 3 is a block diagram showing a configuration of the present invention.

FIG. 4 is a schematic diagram showing a gutter production line according to the embodiment.

FIG. 5 shows the downstream end of the gutter production line;
(A) is its top view, (b) is its side view.

FIG. 6 is a diagram showing a cross-sectional shape of a rain gutter.

FIG. 7 is a diagram showing a schematic configuration of an inspection device.

FIG. 8 is a flowchart illustrating a procedure of an inspection operation.

[Explanation of symbols]

 6 Inspection apparatus 62 High-frequency fluorescent lamp (irradiation means) 63 CCD camera (imaging means) 66 Measurement means 67 Measurement line setting means 68 Edge position calculation means 69 Pass / fail judgment means Pm Reference line (Reference position of specific location) ΔP Position correction amount ( Lm Reference position of measurement line L1 First correction measurement line L2 Second correction measurement line P1 First edge position P2 Second edge position Pt True edge position S1 Outer edge of one side of rain gutter (specific location of inspection object) S2 Lower side of gutter (side to be inspected) S3 Upper side of gutter (side to be inspected) α Integer part of position correction amount β Decimal part of position correction amount

Claims (4)

[Claims] 1. A dimensional inspection apparatus for determining the quality of an inspection object by recognizing dimensions of the inspection object, wherein: an imaging unit for imaging an image of a predetermined area of the inspection object; Based on the obtained and digitized image data, the position of a specific point in the predetermined area of the inspection object is detected, and a reference position of the specific point set in advance is compared with an actual position of the specific point to compare the two. A measuring means for converting the positional displacement amount between the pixels into a pixel quantity comprising an integer part and a decimal part and measuring the position; receiving a pixel quantity data from the measuring means, and a position having a predetermined dimension from the reference position of the specific location The first correction measurement line is set at a position corrected by the number of pixels of the integer part of the displacement amount with respect to the reference position of the measurement line set in advance, and the base of the measurement line is set. A measurement line setting means for setting a second correction measurement line at a position corrected by adding one pixel to the number of pixels of the integer part of the displacement amount with respect to the quasi-position; The edge position of the inspection object is defined as a first edge position, and the edge position of the inspection object on the second correction measurement line is defined as a second edge position. Edge position calculation formula First edge position coordinate + (second edge position coordinate− Edge position calculating means for calculating a coordinate point obtained by a decimal part of (first edge position coordinate) × position shift amount as a true edge position, and obtaining the true edge position for a plurality of portions of the inspection object; A pass / fail judgment which receives the output of the edge position calculating means and recognizes the dimensions of the test object based on the true edge positions at a plurality of positions calculated by the edge position calculating means to judge the quality of the test object. Dimensional inspection apparatus characterized by comprising a stage. 2. The dimensional inspection apparatus according to claim 1, wherein when an image of a predetermined area of the inspection object is captured by the imaging unit, the image of the inspection object is viewed from a direction substantially orthogonal to an imaging direction of the imaging unit. A dimension inspecting device provided with an irradiating means for irradiating light. 3. The dimensional inspection apparatus according to claim 1, wherein the inspection object is a cylindrical body having a substantially quadrangular cross section, and the predetermined area of the inspection object is an end surface on one end side in the extension direction of the cylindrical body. The specific position of the inspection object is an outer edge portion of one side on this end face, and the first edge position of the inspection object is the outer edge of the inspection object side extending in a direction orthogonal to the one side. A dimensional inspection apparatus, wherein the intersection is between the first correction measurement line and the second edge position of the inspection object is the intersection between the outer edge of the inspection object side and the second correction measurement line. 4. A dimension inspection method for determining the quality of an inspection object by recognizing the dimensions of the inspection object, wherein image data obtained by imaging a predetermined area of the inspection object by an imaging unit and digitizing the image data. Then, after detecting the position of the specific portion of the inspection object in the predetermined area, the reference position of the specific portion set in advance is compared with the actual position of the specific portion, and the positional deviation amount between the two is calculated. A measuring step of measuring by converting into a pixel quantity consisting of an integer part and a decimal part, and after this measuring step, the measurement position is set to a reference position of a measurement line preset at a position having a predetermined dimension from the reference position of the specific place. On the other hand, a first correction measurement line is set at a position corrected by the number of pixels of the integer part of the displacement amount, and one pixel is added to the number of pixels of the integer part of the displacement amount with respect to the reference position of the measurement line. Minute Setting a second corrected measurement line at a position corrected by adding and subtracting a position, and setting an edge position of the inspection object on the first corrected measurement line as a first edge position, With the edge position of the inspection object of (1) as the second edge position, the coordinate point obtained by the edge position calculation formula: first edge position coordinate + (second edge position coordinate−first edge position coordinate) × decimal part of positional deviation amount An edge position calculating step of calculating the true edge position and calculating the true edge position for a plurality of locations of the inspection object; and after the edge position calculating step, the true edge positions of the calculated plurality of locations are calculated. A quality determination step of recognizing the dimensions of the inspection target based on the information and determining the quality of the inspection target.