JPH0372206A - Shape checking apparatus of curved plate-like body - Google Patents

Abstract

PURPOSE:To automatically check the curving shape of a curved plate-like body, i.e., glass plate by photographing a light-and-dark line projected onto said glass plate by a camera, and processing the photographed image by an image processing means. CONSTITUTION:A glass plate 78 transferred by a belt conveyor 34 is detected by a position sensor 70, when a detecting signal is output to a control part 64. The control part 64 activates an image processing device 60 upon receipt of the detecting signal. As a result, a shutter camera 56 is driven to photograph the glass plate 78. At this time, since a light from a belt-shaped light source 54 is projected to the glass plate 78, the projecting image and the periphery thereof are photographed by the camera 56 and the image is output to the device 60. The projecting image is brighter than the periphery thereof, so that the boundary therebetween becomes a border line of the dark and bright positions. As the photographed image is processed, the difference between the image formed by the border line and a bright and dark line which has been input beforehand as a reference is read for linear approximation, thereby obtaining an inclination of the linear line. The curving shape, good or bad, of the glass plate 78 is judged in comparison between the obtained inclination of the linear line and an inclination which has been input to the device 60 beforehand as a reference.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is directed to a method in which a curved plate-like body such as a glass plate is placed at a predetermined location.
The present invention relates to a shape inspection device for a curved plate-shaped body that determines whether or not it is bent and formed with a predetermined radius of curvature.

[Conventional technology]

Automotive window glass such as side glass is conveyed on a conveying surface consisting of rollers and gas conveying beds in a forming furnace, heated to the temperature at which it is to be formed, and shaped to the same curvature in the conveying direction along the curvature of the conveying surface. In other words, the curved shape is formed such that the generatrix forming the curved surface faces in one direction. That is, as shown in FIG. 6, the automobile window glass 2 is formed to have a predetermined curvature R. Since this curved shape is usually formed using the lower i2A as a reference line, it has the lower edge 2A and the generatrix 6 having a predetermined inclination. Therefore, if the glass plate 2 is molded with the underline 2A tilted by α° from the position of the regular reference line, the generatrix 8 will also be tilted α° from the regular generatrix 6, as shown in FIG. Lean. In this state, the glass plate 2 is not bent with the correct radius of curvature. Such a bus 18 is distinguished from the regular bus 6 and is treated as a defective product. Conventionally, the inspection of whether the glass plate is bent to a predetermined radius of curvature, that is, the inspection of whether the generating line 6 of the glass plate 2 is in the correct position, as shown in FIG. Judgments were made based on visual inspection and experience. Glass plates with a curvature other than the correct one are considered defective.

[Problem to be solved by the invention]

However, since conventional inspection methods are performed manually, there are problems in that detection accuracy and work efficiency are poor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a shape inspection device for a curved plate-like object that can automatically inspect the bent shape of a curved plate-like object for glass work, etc. do.

Means for Solving the Problem] The present invention (second aspect of the present invention) provides a shape inspection device for a curved plate-like object, in order to achieve the above-mentioned object, a substantially linear bright and dark line is projected onto a curved plate-like object such as a glass plate. means, an imaging means for capturing an image of the bright and dark lines projected onto the curved plate-like body, and a difference between the bright and dark line image and a reference bright and dark line that has been input in advance by processing the captured image. An image processing means that approximates a read straight line and obtains the slope of the straight line, and a determining means that compares the obtained slope with a reference slope that has been input in advance to judge whether the bent shape of the curved plate-shaped body is good or bad. It is characterized by admonishing people.

[Effect]

According to the present invention, after taking out the glass plate formed into a predetermined curved shape in the forming furnace, the glass plate is positioned and arranged at a predetermined position, and the glass plate is set substantially perpendicular to the generatrix of the glass plate. )
Illuminate with a smooth band-shaped light source, image the bright and dark lines projected onto the glass plate with a camera, process the captured image with an image processing means, and create a standard for a normally bent glass plate that has been input in advance. Defective glass plates can be automatically detected by comparing the data.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A shape inspection device for a curved plate-like body according to the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, the shape inspection device 10 for a curved plate-like object has rollers 16.16...
. is rotatably supported by the pedestal 14 via shafts 18, 18, . . . . Rollers 16, 16... are the first
The position of the end portion 16A of the roller 16 gradually rises as the roller 16 on the right side approaches the roller 16 on the left side in the figure.

That is, the roller 16 at the right end is installed horizontally, but the roller at the left end is installed at an angle of 15° to 45°, for example, 30°, in order to determine the angle of the glass plate with respect to the conveying direction.

Further, a pulley 22 is fixed to the end of the shaft 18 via a flexible joint 20. This pulley 22, 22... and the pulley 26, 26 on the pedestal 14 side.
A belt 28 is stretched between.... Furthermore, a belt 32 is stretched between the pulley 26 and the drive pulley 30 on the left side in FIG. 1, and the drive pulley 30 is connected to a motor 33. Therefore, when this motor 33 is driven, the belt 32
．． Since the pulleys 22, 22, . . . rotate via the pulleys 28, the roller 16 rotates.

Adjacent to the leftmost roller 16 in FIG. 1, a belt conveyor 34 is installed at an angle of about 30 degrees. A pulley 38 is fixed to the roller 36 on the left side of the belt conveyor 34 on the opposite side of the pulley 26, and the pulley 38 is connected to a motor (not shown) via a belt 40.

Therefore, when the motor (not shown) is driven, the pulley 38,
A belt conveyor 34 rotates via rollers 36.

Further, in FIG. 1, rollers 16, 16..., rollers 36
A side belt conveyor 42 having rollers 44 extending in a direction perpendicular to the side belt conveyor 42 is provided upright. The rollers 44 of the side belt conveyor 42 are connected to a motor 50 via a shaft 46 and a gear box 48 so as to be able to transmit rotational force. Therefore, when the motor 50 is driven, the gear 48, shaft 46
, the side conveyor 42 rotates via the rollers 44.

A strip-shaped light source 54 is provided above the belt conveyor 34 so as to be substantially orthogonal to the direction of the generatrix of curvature of the glass plate being conveyed, and this strip-shaped light source emits scattered light. If the direction of the band-shaped light source 54 deviates significantly from perpendicular to the direction of the generatrix of curvature of the glass plate being transported, the sensitivity during inspection will drop, so it is preferably substantially perpendicular. At this time, the glass plate may be transported while being inclined so that the generatrix of the curve of the glass plate is substantially perpendicular to the band-shaped light source.

A glossy camera 56 is provided in the center of this band-shaped light source 54. The shutter camera 56 is connected to an image processing device 60 via a cable 58, and the image processing device 60 is connected to a control unit (personal combinator) 64 via a cable 62. Further, the control unit 64 is connected to a position sensor 70 located near the side conveyor 52 via a cable 68. The position sensor 70 is provided on the pedestal 14 via an arm 72.

The operation of the shape inspection device for a curved plate-like body according to the present invention configured as described above will be explained.

Drive motors 33, 50, etc., and drive rollers 16, 16...
is rotated counterclockwise, and the belt conveyor 34 and side conveyor 42 are rotated in the direction indicated by the arrow in FIG.

On the other hand, the glass plate 78 bent and formed on the production line is conveyed to the roller 16 via a conveying means (not shown), and further conveyed in the direction of the belt conveyor 34 by rollers 16, 16, . . . . Since the rollers 16, 16... are gradually rising, the glass plate 78, as shown in FIG.
Due to its gravity, the lower edge abuts against the side belt 52 and is positioned. The glass plate 78 conveyed to the belt conveyor 34 in this state is further conveyed in the same direction by the belt conveyor 34.

FIG. 2 shows the process of detecting defective products, in which the glass plate 78 conveyed by the belt conveyor 34 is
The position sensor 70 is detected (step 90).
outputs the detection signal of the glass plate 78 to the control section 64 via the cable 68. When the control unit 64 receives the detection signal, it operates the image processing device 60 via the cable 62, and the glossy camera 56 operates via the cable 58 to photograph the glass plate 78 (step 92). At this time, as shown in FIG. 3, the light from the band-shaped light source 54 is projected onto the glass plate 78, so this projected image 78A and its surroundings 78B
is imaged by the shutter camera 56. The captured image is output to the image processing device 60 via the cable 58 (
Step 94).

Since the projected image 78A is brighter than its surrounding portion 78B, its boundary becomes a bright-dark boundary line. By determining from the projected image a location where the luminance change is greater than a predetermined value, the curve shown in FIG. 4 is detected as a bright/dark boundary line (edge) (step 96). Next, the detected edge A is determined from a normally bent glass plate and compared with edge B of reference data input in advance. As shown in Figure 4, the vertical axis Y
Setting point Yi (i=l, 2.3,...10
0), the value of the difference Xl-XQi between the coordinate X1 of edge B and the coordinate XOi of edge A in the horizontal 1llIx direction is calculated, and this calculated value is set as ΔX1. That is, △X1=Xi-X01
becomes.

Next, plot (ΔXi, Y) as shown in Figure 5, straighten it using the least squares method, and convert the straight line to Y = A
Display with +B. The slope A of this straight line can be regarded as the slope of the generatrix G of the glass plate 78 shown in FIG. 3 (step 98).

The obtained slope A is compared with a non-defective limit value input into the image processing device 60 in advance. Then step 10
In step 2, if the slope A is within the acceptable product limit, the glass plate 78 is determined to be a specified product; if the slope A is outside the non-defective product limit, the glass plate 78 is determined to be a defective product. Determine (step 102).

Thereafter, the glass plates conveyed by the belt conveyor 34 are sequentially inspected using the above-described inspection method.

〔Effect of the invention〕

According to the shape inspection device for a curved plate-like object according to the present invention, it is possible to automatically inspect all glass plates to see if they are bent and formed correctly, so it is possible to not only improve productivity but also to , inspection of defective products can be made more thorough. In the embodiment of the present invention, a curved plate-like body having a curved surface having the same curvature in the conveying direction of the plate-like body, that is, a curved plate-like body whose generatrix forming the curved surface is oriented in one direction. However, by positioning the plate in a direction perpendicular to the transport direction, it can also be used to inspect curved shapes (such as cones) whose generatrix does not necessarily face in one direction. The range of applications is extremely wide.

[Brief explanation of drawings]

FIG. 1 is a schematic overall view of the shape inspection device for a curved plate-like body according to the present invention, FIG. 2 is a flowchart showing the operating state of the shape inspection device for a curved plate-like body according to the present invention, and FIG. A perspective view showing a state in which a band-shaped light source is projected onto the formed glass plate, Figure 4 is a diagram showing the shape of the edge, Figure 5 is a diagram showing the inclination of the edge, and Figure 6 is a diagram showing the relationship between the glass plate and the generatrix. FIG. 3 is a perspective view showing the relationship. 10... Shape inspection device for curved plate-shaped body, 12...
Positioning means, 16...Roller, 34.42.
...belt conveyor, 54...band-shaped light source, 56
... Shibutsuta camera, 60... Image processing device,
64... Personal combination Niichiyo. Figure 3 Figure ↑

Claims (1)

[Scope of Claims] Means for projecting substantially linear bright and dark lines onto a curved plate-like body; Imaging means for capturing an image of the bright and dark lines projected onto the curved plate-like body; and processing of the captured image. The image processing means approximates the image of the bright and dark lines to a straight line and obtains the slope of the straight line, and compares the obtained slope with a reference slope that has been input in advance to determine the bending shape of the curved plate. 1. A shape inspection device for a curved plate-like object, comprising: a determining means for determining quality.