JPH05157523A - Inspecting method of shape of glass bottle at hot end - Google Patents

Abstract

PURPOSE:To obtain a method for inspecting the defect of the shape of a glass bottle immediately after forming at the hot end correctly at high speeds. CONSTITUTION:The shape of a glass bottle G immediately after molding is photographed by shutter cameras 5, 6, 7 set above and aside a conveyor 1. The shutter cameras have filters capable of negating the influences of the temperature difference of the glass bottle G. As the images are processed, the glass bottle with the degree of deformation exceeding the allowable value is removed before it enters a gradually cooling furnace 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting the shape of a glass bottle at the hot end, which can inspect for shape defects such as the entire length, diameter, and eccentricity before the molded glass bottle enters the annealing furnace. Is.

[0002]

2. Description of the Related Art Conventionally, a glass bottle is sent out of a molding machine and then sent to a slow cooling furnace in a high temperature state, slowly cooled for several tens of minutes, and then inspected for a shape defect by an inspection machine. However, since the defects found in such an inspection after cold cooling (cold end inspection) are related to the glass bottle molded several tens of minutes ago, the inspection result is fed back to the molding process to correct the molding process. There is a delay in the action of doing so, and in some cases, it may be necessary to discard all glass bottles in the annealing furnace as defective products.

In order to avoid such a problem, it is desirable to inspect the glass bottle molded by the molding machine for a geometrical defect or the like before entering the annealing furnace (hot end). However, conventionally, it was not possible to accurately inspect the shape of a glass bottle at several hundreds of degrees Celsius, and there was no other way than to inspect it by cooling the glass bottle pulled out from the conveyor. However, since such a sampling inspection method cannot perform 100% inspection, there is a problem that it is easy to overlook the occurrence of defects.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and allows the hot-end glass to be inspected at high speed and accurately for the geometrical defects of the molded glass bottle. It was made to provide a bottle shape inspection method.

[0005]

In order to solve the above problems, the present inventors first tried to grasp the shape of a glass bottle immediately after molding using a camera used in a cold end inspection. It was However, as is well known to those skilled in the art, a glass bottle molding machine has a large number of molding sections of the same structure, and in order to extrude the glass bottle molded by each molding section onto the same conveyor, which molding section has been molded. The temperature of the glass bottle differs greatly depending on the case, and even the same glass bottle has a partially different temperature. For this reason, it was found that the general camera cannot accurately grasp the entire shape due to the influence of the temperature difference.

However, as a result of further devising the present inventor,
By using a shutter camera with a filter such as red that can cancel the influence of the temperature difference of the glass bottle, it was clarified that the entire shape of the glass bottle immediately after being molded by a normal glass molding machine can be grasped with considerable accuracy. did. The present invention was completed through such circumstances,
The shape of the glass bottle immediately after molding is photographed with a shutter camera with a filter that can cancel the influence of the temperature difference, and the image is processed to detect and eliminate the glass bottle with a degree of deformation exceeding the allowable value. The feature is a glass bottle shape inspection method at a characteristic hot end.

[0007]

The present invention will be described in more detail with reference to the embodiments shown in the drawings. FIG. 1 is a perspective view for explaining an embodiment of the present invention, in which 1 is a conveyor for transferring a high-temperature glass bottle G immediately after it leaves the glass molding machine, 2 is a cross conveyor, 3 is an annealing furnace, and 4 is a cross conveyor 2. The upper glass bottle G is an annealing furnace 3
It is a stacker for pushing into.

In this embodiment, two shutter cameras 5 and 6 are installed directly above the conveyor 1, and one shutter camera 7 is installed horizontally on the side of the conveyor 1. These shutter cameras 5, 6 and 7 used in the examples are all 380,000 pixel CCD cameras,
The outer diameter of the glass bottle G conveyed by the conveyor 1 using an electronic shutter can be captured as a still image. Also, these shutter cameras 5,
Reference numerals 6 and 7 are provided with a filter capable of canceling the influence of the temperature difference. In the embodiment, a red filter having a function of transmitting infrared rays and visible rays close thereto is used, but the red filter is not always limited. Not something.

The images of these shutter cameras 5, 6, and 7 are input to an image processing device and subjected to image processing. Then, the outside diameter and the inside diameter of the mouth are inspected from the images of the mouth portion of the glass bottle G taken by the shutter camera 5 and the shutter camera 6. At this time, as shown in FIG. 2, the shutter camera 5 and the shutter camera 6 are in charge of measurement in the right-angle direction, and by superimposing these images, the outside diameter and the inside diameter of the glass bottle G are measured in both the X and Y axis directions. Can be accurately inspected. From this result, it is possible to easily perform the inspection of the in-mouth ellipticity, which is a problem in the filling line. Further, it is possible to detect the eccentricity defect based on the deviation between the center position of the mouth and the center position of the same.

Further, the shutter camera 7 captures the side shape of the glass bottle G, and the entire length of the glass bottle G can be grasped by image-processing the image thereof. Although the inspection accuracy in the case of the embodiment is 0.78 mm, it is needless to say that the inspection accuracy can be improved if the shutter cameras 5, 6, 7 have more pixels.

As described above, the shape of the glass bottle G is detected, and the glass bottle G having a deformation degree exceeding the allowable value is detected.
With respect to such a glass bottle G, compressed air is jetted from the discharge nozzle 8 provided on the side of the conveyor 1 and dropped onto the discharge chute 9. When the glass bottle G flowing on the conveyor 1 is input to a computer for image processing in which forming section of the glass forming machine is used, the image is binarized accordingly. The threshold of can be changed. According to this method, it is possible to further reduce the influence of the temperature difference due to the difference in the molding section.

In addition, a method of automatically setting a threshold value for binarization according to the maximum value and the minimum value of the brightness level of the image by the automatic calculation processing method can be used together. In this method, as shown in FIG. 3, a video signal of a camera is digitized in multiple gradations by an A / D converter, and a threshold value for converting a binary level to a black and white gradation is set as a threshold value. For example, a method of determining an optimum value for each window by the following formula. Optimal binarization level = X + (Y−X) × α Here, X is the minimum value of the brightness level, Y is the maximum value of the brightness level, and α is a positive small number of 1 or less, for example, 0.5.
If this method is used together, the optimum threshold value can be automatically determined even if the temperature of the glass bottle G is not constant, and stable image processing can be performed.

[0013]

As described above, according to the method for inspecting the shape of a glass bottle at the hot end of the present invention, it is possible to accurately inspect the glass bottle at a high temperature immediately after being molded for any shape defect. The result of the inspection can be immediately fed back to the molding machine to control the molding process. In addition, since geometrical defects can be detected at the hot end, it is possible to eliminate the waste of putting a large amount of defective bottles into the annealing furnace. Therefore, the present invention greatly contributes to the industry as a method for inspecting the shape of a glass bottle at the hot end, which solves the conventional problems.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating an embodiment of the present invention.

FIG. 2 is a plan view for explaining the inspection of the inner diameter of the mouth, the outer diameter of the mouth, and the like.

FIG. 3 is a waveform diagram illustrating a binary level arithmetic processing method.

[Explanation of symbols]

 1 Conveyor 5 Shutter camera 6 Shutter camera 7 Shutter camera G Glass bottle

Claims (1)

[Claims] 1. The shape of a glass bottle immediately after molding is photographed by a shutter camera with a filter capable of canceling the influence of temperature difference, and the image is processed to detect a glass bottle having a degree of deformation exceeding an allowable value. , A method for inspecting the shape of a glass bottle at the hot end, characterized by excluding it.