JP2786070B2 - Inspection method and apparatus for transparent plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a method and an apparatus for inspecting an outer dimension and a curvature of a peripheral portion of a transparent plate-shaped body for determining whether or not a transparent plate-shaped body having a three-dimensional curved surface shape is formed into a desired shape.

[0002]

2. Description of the Related Art As a prior art in a method of inspecting the shape of a transparent plate having a three-dimensional curved surface shape, as disclosed in Japanese Patent Application Laid-Open No. 55-89708, it is known to follow a peripheral edge contour. One that measures with a plurality of probes arranged, and one that has a position measurement sensor at the tip of a movable arm as shown in Japanese Patent Application Laid-Open No. 58-198710, and learns the measurement position sequence based on a reference type. Measurement is carried out by repeatedly reproducing the stored contents, and further, a substantially linear light-dark line is projected on the object to be inspected as shown in JP-A-3-72206. In addition, there is known a method in which a slope obtained by linearly approximating an image of a light-dark line is compared with a reference slope to determine the quality of a bent shape.

[0003] However, among the detection methods described above,
JP-A-55-89708, JP-A-58-198710
In any of the above methods, the sensor is a contact type, and it is inevitable that the object is damaged and the sensor itself is worn. Also, JP-A-3-72206
Also, when measuring an object to be inspected that has a deeply bent shape such as a front glass of an automobile, the inspection accuracy is deteriorated because the inspection is performed from a high position above, and there is a problem in practical use. There is a problem.

For the non-contact type, the present applicant has proposed a curved surface shape measuring method and its apparatus in Japanese Patent Application Laid-Open No. 1-174907, and a glass edge detecting apparatus in Japanese Patent Application Laid-Open No. 1-187403, all of which are three-dimensional. The coordinate system is set, and based on this, the edge of the transparent plate is measured by a position sensor using a laser light source and compared with the virtual curved surface in the design, and the inspection is performed. Since the point is suddenly changed and the point is measured, it is necessary to move the sensor so as to intersect with the seaming part, which complicates the control and may possibly shorten the measurement time.

[0005] The applicant of the present invention has disclosed Japanese Patent Application No. Hei 4-231662.
As a reference, a curved surface shape measurement method and its device have been proposed.However, measurement of external dimensions and curvature requires separate light sources and cameras, and cannot be measured at the same time. However, when there are many inspection points, there is a problem in the processing speed.

The present invention has been made in view of the above points, and has as its object to provide an apparatus for quickly inspecting the outer dimensions and curvature of a transparent plate using a simple apparatus.

[0007]

[Means for Solving the Problems] The inspection method of the present invention comprises:
With the transparent plate with the edge part seamed, placed on the inspection mold and positioned, the edge part of the transparent plate is irradiated with slit light from the laser light source so as to cross the seaming part, The diffused light is imaged by a two-dimensional camera, and the displacement of the image of the seaming portion in the horizontal direction and the vertical direction with respect to the standard value of the transparent plate body stored in advance is calculated, and the deviation between the external dimensions and the curvature is within an allowable range. The inspection apparatus embodying the present invention is characterized in that the pass / fail is determined based on whether or not there is a transparent plate at an inspection position substantially on an extension of the end face of the transparent plate. A laser light source combining a cylindrical lens and a laser is provided in the normal direction of the body, and the inspection of the transparent plate is performed substantially on the extension of the end face of the transparent plate. Normal and 30 ° ~60 ° at the location
And the horizontal and vertical displacements of the grayscale signal obtained by the two-dimensional camera with respect to the previously stored standard value of the transparent plate are calculated, and the deviation between the external dimensions and the curvature is calculated. It is characterized by having at least an arithmetic processing unit for calculating whether or not it is within an allowable range.

[0008]

The present inventors dispose a laser light source and a two-dimensional camera in a specific direction with respect to the edge of a transparent plate having a three-dimensional curved surface such as a plate glass, thereby forming a seamed transparent plate. The edge portion of the transparent plate can be detected, and as a result, the outer dimensions and the curvature of the transparent plate can be inspected simultaneously. A laser light source having a built-in cylindrical lens is disposed in the normal direction of the plate-like body, and is approximately 30 ° from the normal line at a location where the transparent plate-like body is inspected, substantially on an extension of the end face of the transparent plate-like body. 2 to 60 °, preferably 40 ° to 55 °.
By installing a three-dimensional camera and calculating the displacement between the light and shade signals of the seaming part of the transparent plate-like body imaged by the camera and the seaming part of the standard transparent plate-like body, the external dimensions with a set of light source and camera In addition, by irradiating a slit light from a laser light source so as to cross the seamed portion of the transparent plate, a light source and a camera (light receiver) are disclosed in Japanese Patent Application Laid-Open No. 1-174907. ) Eliminates the need to move to cross the seaming portion at the inspection point, and the inspection can be performed by moving it continuously along the outer periphery of the plate-like body, so that the processing speed is significantly improved. It is.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic side view showing an inspection apparatus of the present invention, and FIG.
FIG. 3 is a system configuration diagram in an embodiment of the present invention, FIG. 3 is a perspective view of a main part showing an arrangement of a two-dimensional camera and a light source with respect to a transparent plate in the embodiment of the present invention, and FIGS. FIG. 6 is an enlarged front view of a part of FIG. 5 (a laser light source and a two-dimensional camera are represented by dots), and FIG. 7 is an image taken by a two-dimensional camera. FIG. 7 is a diagram showing a processed image.

First, the inspection apparatus will be described. As shown in FIG. 1, a vehicle window glass or the like, which is transferred by a transfer device (not shown) and positioned to an inspection mold 1 that is rotatable and has precisely manufactured external dimensions, curvature, and the like, is precisely manufactured. placing the transparent plate-shaped object 2 having a three-dimensional curved surface shape, a cylindrical lens (not shown) with the laser such as a semiconductor laser as a light source in the robot hand 3 ₁ of the distal end portion of the movable arm of the six-axis articulated handling robot 3 Combined laser light source 4 and CCD as test solution camera
A two-dimensional camera 5 such as a camera is attached and fixed.

The output of the two-dimensional camera 5 is, as shown in FIG.
The data is input to the arithmetic processing device 8 composed of the above. The robot can be moved to any position on the three-dimensional curved surface by the controller 9.

A case where an arbitrary edge of the transparent plate is inspected by such an inspection apparatus will be described. In a state where the transparent plate is rotated by a driving device (not shown),
According to pre-order taught to the robot controller 8, the robot 3 is driven by the operation of the robot hand 3 _1, the laser light source 4 and the two-dimensional camera 5, as shown in FIGS. 3 to 6, the laser light source is a transparent plate In the direction of the normal H of the transparent plate at the point to be inspected, which is substantially on the extension of the end face of the transparent body, the two-dimensional camera is substantially on the extension of the end face of the transparent plate, and the normal H Angle is 30 ° -60
The robot moves while maintaining a positional relationship within a range of, for example, 50 degrees.

First, as a sample, a transparent plate-like body such as a standard-size sheet glass having an outer dimension and a curvature within a specified range is manually inspected at a plurality of inspection points with respect to a plurality of inspection points and a precisely manufactured inspection mold. the difference in the measured and stored in the personal computer 7, further a transparent plate-shaped object 2 _s of the sample by the apparatus, to image the seaming portion over the entire circumference.

From the laser light source, for example, the width is 0.5 mm,
When the slit light S having a length of 60 mm is irradiated so as to intersect the seaming portion at a right angle, the image at an arbitrary inspection point captured by the two-dimensional camera 5 becomes the upper seaming as shown by a dotted line in FIG. The part a ₁ -b ₁ is clearly displayed, and a ₁ and b ₁ are coordinated by the image processing device 6 in the horizontal direction (x axis) and the vertical direction (y axis), that is, a ₁ is (a _1x , a _{1 1y} ), b ₁ is converted to (b _1x , b _1y ) and stored in the personal computer 7 together with the inspection points.

Next, the transparent plate 2 to be inspected is placed on the inspection die 1 and positioned, and the inspection die 1 is rotated.
The robot 3 is operated, and the inspection is performed while the laser light source 4 and the two-dimensional camera 5 are moved at a fixed angle with respect to the seaming portion (a ₂ -b ₂ ) of the transparent plate 2.

At an arbitrary inspection point, for example, a slit light S having a width of 0.5 mm and a length of 60 mm
Is irradiated so as to intersect the seaming portion at a right angle, the image taken by the two-dimensional camera 5 clearly shows the upper seaming portion a ₂ -b _{2 as} shown by the solid line in FIG. _With respect to ₂ and b ₂ , the image processing device 6 sets the coordinates in the horizontal direction (x axis) and the vertical direction (y axis), that is, a
₂ is converted to (a _2x , a _2y ) and b ₂ is converted to (b _2x , b _2y ) and output to the personal computer 7, where the external dimensions and curvature are inspected.

As shown in FIG. 4, the external dimension difference h ₀ between the test mold and the sample transparent plate 2 _s measured and stored in the personal computer 7 in advance and the transparent object to be inspected, as shown in FIG. It is expressed as a difference (h ₀ −h ₁ ) between the outer dimension difference h ₁ of the plate-shaped body 2 and the transparent plate-shaped body 2 _s of the sample, and h ₁ is b in the horizontal direction (x-axis) in FIG. ₁ and b ₂
Is the difference (b _2x −b _1x ).
₀ + b _1x −b _2x ). If this value is +, it indicates that the outer dimensions of the transparent plate 2 are smaller than the inspection type, and if −, it is larger than the inspection type, and the absolute value is a predetermined value. If it is smaller, it is judged as pass, and if it is larger, it is judged as failed.

Regarding the curvature, FIG.
Transparent plate 2_sStored in personal computer 7
Measured curvature h_TwoAnd the sample transparent plate 2_sAnd received
Difference h in the normal direction H of the transparent plate 2 as the inspection object_Three(Sun
Pull transparent plate above the transparent plate to be inspected
(Sometimes +, below-))
(H_Two-H_Three) And h_ThreeIs the triangle a in FIG.₁a_Two
In d, a_Twod (a _Twod) / cos
θ and a_Twod (a_Twod shows the distance between d)
A in the vertical direction (y-axis)₁And a_TwoDifference (a_1y-A_2y)
Therefore, the required curvature is (h_Two− (A_1y-A_2y) / C
osθ), and if this value is within a predetermined standard, it passes.
If it is out of the standard, it is judged as reject.

According to the present invention, the above-described inspection is performed continuously over the entire periphery along the periphery of the transparent plate.
The inspection could be completed in a few seconds even if the inspection was performed for several hundred points, and the processing speed was remarkably improved.

The external dimensions and curvature data measured by the personal computer may be displayed on a monitor display device, stored and used as management information, and the generated defect information is immediately fed back to the preceding molding process. May be.

Although the preferred embodiments have been described above, the present invention is not limited to these, and various applications are possible. Regarding the laser light source that irradiates the slit light to the seaming portion, in order to change the normal laser light to the slit light, it is preferable to use the combination with the cylindrical lens shown in the embodiment, but the laser light is transparent with a polygon mirror instead of the cylindrical. The plate-like body may be moved so as to cross the seaming portion. The mounting position of the laser light source is in the direction of the end face of the transparent plate-like body and is preferably in the direction of the normal line H. However, the laser light source is shifted by about 30 ° to the right and 10 ° to the left in FIG. 5 and 6, the angle with respect to the normal is also ± 10 °, that is, 10 °.
If it is about °, it may be shifted to the left and right. Further, it is preferable to irradiate the slit in the direction in which the slit intersects the seaming portion at a right angle. The smaller the width of the slit, the better
The length should be larger than the field of view of the camera.

For the two-dimensional camera, a two-dimensional area sensor using a CCD is preferable. However, a one-dimensional camera may be used to store signals and perform two-dimensional processing. The angle φ with respect to the normal in FIGS.
4 ° to 60 °, preferably 40 ° to 55 °, and 30 ° to the right in FIG.
° and about 10 ° to the left.

With respect to the standard values of the outer dimensions and the curvature, in the embodiment, the difference between the precisely manufactured inspection die and the sample plate is obtained in advance, and the difference between the inspected plate and the sample plate is obtained. From these results, the outer dimensions and curvature of the plate to be inspected with respect to the inspection mold were further determined. That is, the inspection mold was used as a standard value. If there is no error, or if there is an error, the accuracy of the inspection mold is not required, and the dimensions and curvature of the plate-like body of this sample may be set as standard values. Further, when the standard value at each inspection point is given as design data, it may be converted into coordinates at each inspection point based on this and used as the standard value. In this case, not only the accuracy of the inspection mold is not required, but also it is not necessary to use a sample plate.

In order to precisely inspect a transparent plate having a three-dimensional curved surface as in the embodiment, a robot having six or more axes of freedom is required. In the case where the inspection is performed or the inspection accuracy may be low, a robot having five or less axes of freedom can be used. In addition, not only a unit integrally manufactured as a robot, but also a unit in which drive units for each axis are separately manufactured and combined.

In the embodiment, the processing speed is improved by rotating the inspection mold and following the laser light source and the two-dimensional camera. However, the transparent plate is kept stationary, and the laser light source and the two-dimensional camera are stopped.
The inspection may be performed by moving only the three-dimensional camera by the robot.

The object to be inspected can be applied not only to a plate glass but also to a transparent resin or the like. Of course, other than a transparent plate having a three-dimensional curved shape, a flat shape may be used.

[0027]

As described above, according to the present invention, since the measurement is performed by the non-contact method using the two-dimensional camera, the object to be inspected is not damaged and the detection sensor may be worn. In addition, since the laser light source emits light so as to intersect the seamed part of the test object, there is no need to move the light source to the seamed part at the inspection point, and the light source and the two-dimensional camera are specified for the seamed part. By arranging them in a range, only one set is required, and as a result, inspection can be performed simultaneously, thereby significantly improving the processing speed.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing an inspection device of the present invention.

FIG. 2 is a system configuration diagram in an embodiment of the present invention.

FIG. 3 is a view illustrating a transparent plate-shaped member according to an embodiment of the present invention;
It is a principal part perspective view which shows arrangement | positioning of a three-dimensional camera and a light source.

FIG. 4 is a side view of a main part showing the inspection apparatus in the present embodiment.

FIG. 5 is a front view of a main part showing the inspection apparatus in the present embodiment.

6 is an enlarged front view of a part of FIG. 5 (a laser light source and a two-dimensional camera are indicated by dots).

FIG. 7 is a diagram showing an image captured by a two-dimensional camera.

[Explanation of symbols]

Reference Signs List 1 inspection type 2 transparent plate 2 _s sample transparent plate 3 robot 4 laser light source 5 two-dimensional camera 6 image processing device 7 personal computer 8 arithmetic processing device 9 controller

Claims (2)

(57) [Claims] A slit light from a laser light source is applied to the edge portion of the transparent plate so as to cross the seamed portion while the transparent plate having an edge portion seamed is placed on an inspection mold and positioned. Then, the diffused light of the seaming portion is imaged by a two-dimensional camera, and the displacement of the image of the seaming portion in the horizontal direction and the vertical direction with respect to the standard value of the transparent plate member stored in advance is calculated. A pass / fail judgment is made based on whether or not is within an allowable range. 2. A transparent plate having an edge portion seamed is placed on an inspection mold and positioned, and light from a light source is applied to the edge portion of the transparent plate. In the device for inspecting the curvature and the outer dimensions of the transparent plate by imaging the portion, in a direction substantially normal to the end face of the transparent plate and in the normal direction of the transparent plate at the location to be inspected, A laser light source combining a cylindrical lens and a laser is provided, and is approximately on an extension of the end face of the transparent plate-like body, and is in a range of 30 ° to 60 ° with respect to a normal line at a location where the transparent plate-like body is inspected. The horizontal and vertical displacements of the light and shade signals obtained by the two-dimensional camera with respect to the previously stored standard values of the transparent plate are calculated, and the deviation between the external dimensions and the curvature is within an allowable range. Whether or not An apparatus for inspecting a transparent plate-shaped object, comprising at least an arithmetic processing unit for performing an operation.