JPH04295703A - Method for detecting position of side edge part of applied film - Google Patents

Abstract

PURPOSE:To obtain the method for detecting the position of the side edge of an applied film for improving quality control so that parts which are not covered with the applied film are not mixed into a product by correctly detecting the position of the side edge part of the applied film, rationalizing the machining inspection after cutting, and decreasing the loss in yield. CONSTITUTION:Infrared rays are emitted from an infrared-ray projector 1 on a web edge 3 of an applying-agent web 2 and an applied-film side-edge position 4. The image is picked up with a two-dimensional image sensor camera 5 and sent into an image processing device 6 as a video signal. In the image processing device, binary coding 7, applied-position identification 8 and base-edge identification 9 are performed. The deviation is operated, and limit check 10 is performed. The result is recorded in an analog-output recorder 11.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process of applying a coating liquid composition onto a continuously running web, and more specifically to a method of detecting whether there is any abnormality in coating at the edge position of the coating film.

0002

2. Description of the Related Art Conventionally, there has been no means for detecting the side edges of a coated film. Therefore, when processing a coated web, cutting is performed with the inner side as the end in consideration of the possibility that the side edges may not be coated correctly during coating.

0003

[Problem to be solved by the invention] However, if an uncoated part occurs within the width of the product due to an abnormality in the coating process, it may be overlooked during cutting, so it is necessary to conduct a thorough inspection during processing. In addition, if the coating is performed correctly, cutting off parts that can be used as a product will result in a large loss in yield, so a method for correctly detecting the position of the edge of the coating film has been desired. The purpose of the present invention, in response to the above-mentioned demands, is to accurately detect the edge position of the coated film on-line, to streamline processing inspection after cutting, to reduce losses in yield, and to prevent uncoated parts from contaminating products. An object of the present invention is to provide a method for detecting the position of the edge of a coating film in order to improve quality control.

The above object of the present invention is to project light onto a coated web using an infrared projector, detect the coated film side edge using an image sensor, and detect the coated film side edge in combination with the detected value of the web edge. A method for detecting the position of an edge on a coated film side, the method comprising detecting an uncoated portion of a coated film. achieved by

[0005] The infrared projector used in the present invention projects light obliquely onto the web side end from the upper side opposite to the web side end to be inspected. The image sensor of the present invention is convenient for photographic paper, etc., which has a high reflectance, because the one-dimensional image sensor can detect both the coating film side edge and the web edge. In case,
Although the edge of the coating film can be detected with a one-dimensional image sensor, the detection of the web edge requires the use of a two-dimensional image sensor and image processing such as linear approximation. Alternatively, a one-dimensional image sensor is used to detect the edge of the coating film, and the web edge is detected using a conventional edge detection control device (
EPC) may be used to detect uncoated areas in combination with the detected value. The coating film end position detection method of the present invention can also be applied to EPC.

[0006]

[Embodiment] One embodiment of the present invention will be explained in detail with reference to the drawings. In the inspection process and circuit diagram of FIG. 1, an infrared projector 1 irradiates infrared light onto the web edge 3 and coated film side end position 4 of the coated web 2. The image is captured by a two-dimensional image sensor camera 5 and sent to an image processing device 6 as a video signal. The image processing device converts the received video signal from analog to digital by applying it to the image binarization circuit 7, and in this case, images with good S/N can be obtained by incorporating web quality information and optimizing it according to the type of web. can get. Aluminum vapor-deposited tape is used at the joint, and the application position and joint tape cannot be identified from analog signals, and it is determined that the application position is abnormal, resulting in a false alarm. Therefore, in the limit check after binarization, if the limit is reached for two consecutive scans, we will assume that an abnormal coating position has occurred.
It was determined that it was an uncoated area. Details are as follows. The joining tape width is 50mm, and the image input cycle is 33msec.
When the width of the camera field of view is 1 mm, the time it takes for the tape to pass through the camera field of view depends on the line speed. For example, if the line speed is 100m/min (1666mm/
sec), the distance the bonding tape passes through the camera field of view is 50+1mm, and the passing time T=(passing area=51mm)/1666=
It becomes 30.6 msec. Since the passing time is shorter than the image input time, the splicing tape will not be detected twice in two scans. Therefore, at this line speed, the case where detection occurs twice in two scans is regarded as a coating abnormality, and the joining tape detection and the coating position abnormality are distinguished. When this detection method is applied at a line speed of 100 m/min or less, the joining tape may be detected twice within two scans. This case can be dealt with by lengthening the image input cycle. Next, based on this, a coating position identification 8 is carried out, a base edge identification 9 is carried out, a deviation from the base edge to the coating position is calculated, a limit check 10 is carried out, and finally it is recorded in an analog output recording system 11. This record provides information on uncoated areas, which can be used as a reference for rationalization and quality assurance.

[0007]

Effects of the Invention: The coating film side edge position detection method of the present invention allows the state of the coating film edge to be accurately grasped, which streamlines processing inspection after cutting, reduces loss in yield, and prevents uncoated parts from being coated. Quality control can be performed to prevent parts from being mixed into products.

[Brief explanation of drawings]

FIG. 1 is an inspection process and circuit diagram of an embodiment of the coating film side edge position detection method of the present invention.

[Explanation of symbols]

1 Infrared floodlight 2 Coated web 3 Web edge 4 Coating film side end position 5 Two-dimensional image sensor camera 6 Image processing device 7 Image binarization circuit 8 Application position identification 9 Base edge identification 10 Limit check 11 Analog output and recorder

Claims (1)

[Claims] Claim 1: An infrared projector emits light onto the coated web, an image sensor is used to detect the edge of the coated film, and the uncoated portion of the edge of the coated film is detected by combining it with the detected value of the web edge. A coating film side edge position detection method characterized by: detecting a coating film side edge position.