JPH0240542A - Apparatus for detecting foreign matter in dry laver - Google Patents

Abstract

PURPOSE:To make it possible to perform accurate detection of foreign matters with a detecting means without a movable part that is the cause of malfunction by passing dry lavers on a light source, and detecting the change in passing light with a TV camera. CONSTITUTION:When dry laver is conveyed with a belt conveyer 1, an input sensor 13 detects the laver. A standby state of the detection of foreign matter is set. When the laver is moved on guide plates 6 and 7, a TV camera 9 scans them with passing light of light from a light source 8 along the longitudinal direction. When a shaded part (part where the amount of light is decreased) exists on said scanning line, the size and the position of the shaded part are recorded in a memory. When the shaded parts exist at the close positions on the specified continuous lines, the foreign matter having the specified size or larger is determined, and the number of the matters is stored in the memory. When the scanning is finished, the number of the foreign matters is read. When one or more matters are recorded, a shutter 10 is turned, and the laver is dropped into a defective product containing part 11 as a defective product. When the number is zero, the laver is conveyed into a good product containing part 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for detecting contaminants attached to dried seaweed.

[Conventional technology]

In the dry seaweed sorting line, it is necessary to determine the shape and detect foreign substances attached to the surface. In this,
A television camera is used to determine the shape, and if the shape does not meet a predetermined shape, it is ejected from the line by an ejector such as a shutter placed on the line.

By the way, there are various foreign substances that adhere to dried seaweed, such as shells, insects, vinyl, iron pieces, wood chips, straw waste, feathers, and paper (hereinafter, these foreign substances are referred to as foreign substances). In the past, workers were stationed on the line to manually remove dried seaweed with foreign matter from the line.

However, since dried seaweed with foreign objects is removed by visual inspection by 11 people, it is inevitable that foreign objects that are difficult to identify will be overlooked. Therefore, dried seaweed that is not desirable as a product passes through the line, and the original purpose of sorting cannot be achieved, and the time required for sorting becomes longer, which becomes an obstacle to improving productivity.

Furthermore, since workers must be continuously placed on the line during the sorting process, labor costs increase and product costs are also affected. The applicant previously developed the following foreign object detection device (Japanese Patent Application Laid-Open No. 62-2125).
Publication No. 53). This device has a pair of upper and lower foreign object detection rolls arranged on the pass line of dried seaweed, one of the detection rolls can be displaced vertically with respect to the pass line, and a sensor is provided to detect the displacement. When dry seaweed mixed with foreign matter is conveyed to the pass line, the foreign matter becomes thicker than the set thickness of the dried seaweed, and the detection roll is displaced, so that it can be removed from the pass line as a defective product.

[Problem to be solved by the invention]

However, with the foreign object detection device proposed in the future,
It is not effective against foreign objects that cannot be detected by the vertical movement of the detection roll, and there is also the problem that the detection roll moves slightly up and down when it bites into accepted dried seaweed, making it easy to malfunction.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a detection means that does not have a movable part that may cause malfunction, and to perform accurate foreign object detection.

[Means to solve the problem]

In order to achieve this purpose, the dried seaweed contaminant detection device of the present invention includes a television camera installed on the dry seaweed transport line, a light source installed below the transport line, and the light irradiated by the light source detects the dry seaweed. The present invention is characterized by comprising means for observing changes in the amount of light transmitted through the television camera using the television camera, and generating a contaminant signal when the amount of light becomes less than a set value.

As a result of research, it has been found that dried seaweed can easily transmit light with wavelengths between 650 and 1500 nm, so it is important to include the center wavelength of the light source and the wavelength characteristics of the television camera within this range to distinguish contaminants from dry seaweed. It is suitable for separate detection.

〔Example〕

Hereinafter, the present invention will be specifically described based on embodiments shown in the drawings.

FIG. 1 is a schematic diagram showing an embodiment of a contaminant detection device of the present invention, and FIG. 2 is a sectional view taken along the line II in FIG. 1.

In the figure, Δ is rectangular dried seaweed, 1 and 2 are belt conveyors for transporting the seaweed, and 3 to 5 are pressing rollers. Guide plates 6 and 7 are provided between the belt conveyors 1 and 2, onto which the dried seaweed A is sent. Guide plate 6.
A light source 8 is installed at the bottom of 7, and a television camera 9 is installed above. When a foreign object is detected by the television camera 9, a shutter 10 is activated to drop the dried seaweed into a defective product storage section 11. Good products pass through the shutter 10 and are transferred to a good product storage section 12 at the rear. 13 in the diagram
is an entry sensor that detects that the dried seaweed A is carried in by the belt conveyor 1.

When the dry seaweed A is transported by rollers on the guide plates 6 and 7, the light from the light source 8 that has passed through the dry seaweed A is imaged by a television camera 9. As the TV camera 9, C
A line image sensor such as a CD array can be used.

When visible light is used as the wavelength of the light source, it is difficult to distinguish between dried seaweed and foreign substances.

As a result of the study, dried seaweed is 650 ~
It was found that the transmittance is high at a wavelength of 150 hm, that is, in the near-infrared region. Foreign objects such as shells, insects, vinyl, iron pieces, wood chips, straw waste, feathers, and paper have difficulty transmitting light in this wavelength range, so the television camera 9 detects foreign objects by detecting changes in the amount of light. be able to.

FIG. 4 shows a flowchart of foreign object detection. First, when the dried seaweed A is carried in from the belt conveyor 1, the entrance sensor 13 detects this and enters a standby state for foreign matter detection. When the dried seaweed A is transferred onto the guide plates 6 and 7, the television camera 9 scans the transmitted light from the light source 8 along the longitudinal direction of the light source 8.

If there is a portion where the amount of light decreases in the scanning line, that is, a shadow, the size and position of the shadow are recorded in a memory or the like.

If there is a shadow in a position close to a predetermined continuous row, it means that there is a foreign object larger than the size of the -chamber. The number of shadows recognized as foreign objects is stored in memory.

When the shadow disappears and all of the seaweed has been scanned, the number of foreign objects is read out from the memory, and if one or more foreign objects are recorded, the solenoid that rotates the shutter 10 shown in Figure 1 is activated, and the product is rejected as a defective item. Drop it into the good product storage section 11. When the number of foreign objects is 0, the shutter 10 does not operate, and the dried seaweed is transported to the good product storage section 12. Alternatively, it can be carried out to the next line for a dry seaweed shape determining device or a dry seaweed binding device.

By detecting changes in the amount of light passing through the dried seaweed in the manner described above, foreign object detection can be performed continuously.

In the above embodiment, the entrance sensor 13 detects the entry of the dried seaweed, but the video of the television camera 9 can also be used to detect the starting end and #end of the dry seaweed.

In addition, the center wavelength of the light source and the wavelength characteristics of the television camera are set to 6.
Although a preferred example of wavelength range from 50 to 1500 nm is given, it is of course possible to detect at other wavelength ranges.

〔Effect of the invention〕

As explained above, in the present invention, foreign matter is detected by causing dried seaweed to pass over a light source and detecting changes in the transmitted light using a television camera. In this way, since foreign objects can be detected without contacting the dried seaweed, malfunctions can be reduced and the yield of dried seaweed products can be increased.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line I-I in Fig. 1, and Fig. 3 shows the wavelength characteristics of light absorption and transmittance 1 reflectance of dried seaweed. Graph 1. FIG. 4 is a flowchart of foreign object detection processing according to the present invention. A; Rectangular dried seaweed 1.2: Belt conveyor for transporting seaweed

Claims (1)

[Claims] 1. A television camera is installed on the dry seaweed transport line,
A light source is installed below the conveyance line, and the television camera observes changes in the amount of light emitted by the light source as it passes through the dry seaweed, and when the amount of light falls below a set value, a contaminant contamination signal is generated. A device for detecting contaminants in dried seaweed, characterized by comprising means for detecting contaminants in dried seaweed. 2. The center wavelength of the light source and the wavelength characteristics of the TV camera are 65
The device for detecting impurities in dried seaweed according to claim 1, characterized in that the wavelength is between 0 and 1500 nm.