JPH0277610A - Method for automatically sorting object - Google Patents

Abstract

PURPOSE:To enhance accuracy by eliminating an error in failing to distinguish between an object and a belt by placing the object on the belt, to which regular reflectivity or reflective ability is imparted, to project light on the object from above and distinguishing the object from the belt on the basis of the quantity of reflected light. CONSTITUTION:Fine globules 2 are closely adhered to the upper surface of a base belt 1 and a transparent synthetic resin coating film 3 is provided on said fine globules to form a belt 4. For example, clams 9 are fed to the belt 4 of a belt conveyor 5 at an appropriate interval as objects to be sorted while the belt conveyor 5 is moved in the direction shown by an arrow 8. Next, when the belt 4 and the clams 9 are irradiated with light from a light source 6 as shown by fan arrow 10, the reflected light shown by an arrow 11 is emitted from the surface of the belt 4 of the belt conveyor 5 and light is irregularly reflected form the clams 9 as shown by arrows 12, 13. Consequently, when these reflected lights 11-13 are caught by a camera 7, the images of both of the belt 4 and the clams 9 are clearly discriminated on the basis of quantity-of- light difference.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for sorting objects by capturing reflected light rays.

(Prior art) Conventionally, to sort out the quality of clams, the clams were placed on a belt with relatively low reflective performance, and light was projected onto the belt to detect the difference in the amount of reflected light between the belt and the clams, thereby distinguishing between the belt and the clams. Experiments were being conducted to sort out the size of clams.

A method has also been tried in which an object is conveyed by a mesh belt and an image of the object is measured using a beam of light projected from below the mesh belt.

(Problem to be Solved by the Invention) However, in the above implementation, when the surface of the clam turns black, it becomes difficult to distinguish the amount of reflected light from the belt, and there is often a risk of misunderstanding the size. It was also difficult to sort out shellfish with different colors.

Furthermore, the surfaces of natural objects such as shellfish are irregularly uneven and usually reflect diffusely, making it difficult to capture the projected light beam at a high level.

In addition, in the method of projecting light from below using a net belt and photographing the shadow of an object, it is possible to prevent water droplets and other foreign objects from falling,
It was recognized that there is a risk that not only the image may be distorted but also the projected light beam may be disturbed due to interference, and that problems are likely to occur with long-term use.

(Means for Solving the Problems) In the present invention, an object is placed on an endless strip that has retroreflectivity, and the reflection level of the endless strip is significantly improved with respect to the object. The above-mentioned problems of the prior art have been solved by reliably detecting an object and measuring its area based on the amount of color, and by detecting the object on the color tone side.

That is, in this invention, an object is placed on an endless strip that is specularly reflective or retroreflective, and light is projected from above, and the object and the endless strip are distinguished from each other based on the amount of reflected light to calculate the planar area of the object. This automatic object sorting method is characterized by measuring objects and sorting them by size based on the flat area, and if necessary sorting by color. Furthermore, the zero-order retroreflectivity is achieved by comparing the reflection level of an object with a set value and selecting those that are below the set value, by attaching microscopic transparent spheres. Furthermore, specular reflection is imparted by providing an aluminum layer.

The above-mentioned process for specular reflection or retroreflection should be different as long as the reflected light ray of the object to be measured and the reflected light ray of the endless band can be clearly distinguished.

Therefore, it is conceivable to provide an aluminum layer (deposited or coated) as a specular reflection surface. In this case, by providing an aluminum vapor deposition layer or coating aluminum powder on the base sheet surface, and covering the top surface with a transparent film, a specularly reflective endless strip sheet can be obtained.

The endless belt sheet mentioned above can also be manufactured by bonding an aluminum vapor-deposited film to the base sheet surface.

Furthermore, an endless belt sheet having a retroreflective surface is constructed by pasting microscopic transparent spheres (made of glass or synthetic resin) on the upper surface of a base sheet, and providing a transparent synthetic resin layer on the upper surface.

This invention can be used to automatically sort objects of irregular shape, such as shellfish (for example, shellfish), other fruits, or various industrial products, or objects sent at random in size or color, by size or color.

(Function) In this invention, since the endless strip is subjected to specular reflection treatment or retroreflection treatment, the reflected light beam is retroreflected, clearly distinguishing it from the diffuse reflection of the object, and the shape of the object can be clearly seen. can be detected.

(Example 1) An example of the present invention will be described with reference to FIGS. 1 to 3.

That is, glass microspheres 2 are placed on the top surface of a strong base belt 1.
A transparent synthetic resin coating 3 is provided on the upper surface of the microspheres 2 to form a belt 4 (endless band). The belt 4 constitutes a belt conveyor 5, a light source 6 is provided above the belt conveyor 5, and a camera 7 is installed at an appropriate location.

In the above, while the belt conveyor 5 is moved in the direction of the arrow 8, for example, clams 9 are fed in as objects to be sorted at appropriate intervals. Then, reflected light rays shown by the arrow 11 are emitted from the 4th surface of the belt of the belt conveyor 5, and reflected light rays shown by the arrow 12 are emitted from the clam 9.
．． It reflects diffusely like 13. Therefore, when these reflected light beams (arrows 11, 12, and 13) are captured by the camera 7, the images of the belt 4 and belt 9 can be clearly distinguished based on the difference in light intensity (FIG. 2).

In addition, images that are relatively white and images that are black are captured on the tonal side. Clam 9, which is almost white as described above,
The area of the slightly blackened clam 9a was measured, and the whole clam 9.9a was measured.
can be sorted not only by area but also by color tone. As shown in FIG. 3, such sorting is performed by capturing an image with a camera 7 using reflected light, measuring the area of the number of dots in this image with a calculator 14, and calculating the area and setting with a setting device 15. A comparator 16 compares the values, and depending on a predetermined level, commands such as A, B, C, etc. are issued, and the controller 17 selects them. In addition, it is possible to sort by color tone based on the black point level and set value. Regarding the sorting, as shown in FIG. 6, the pieces are thrown out from the belt 4 onto the sorting belt 21 by the springing piece 20. By setting a required number of jump-out pieces on the belt 4 and laying a sorting belt corresponding thereto, it is possible to sort items into a large number of levels as required.

(Example 2) This example is an example of a specular reflection belt in which an aluminum vaporized layer 18 is provided on a strong base belt 17, and the upper part thereof is covered with a transparent film 19.

(Effects of the Invention) This invention places an object on an endless band with specular or retroreflective properties, projects light from above, and distinguishes between the object and the endless band based on the amount of reflected light. Since the surface distribution was measured and the output was used to activate the controller, it was possible to clearly distinguish between the object and the endless band. Therefore, there is no error caused by misidentifying the object and the endless band, which has the effect of improving accuracy. Furthermore, by setting the level of reflected light from an object, color tones can be automatically selected based on the amount of reflected light.

If microspheres are used in the treatment of the endless band, there is an effect of improving retroreflection performance, and if an aluminum evaporated layer is used, there is an effect of improving specular reflection performance.

In any case, since natural or artificial objects and endless bands rely on reflective performance, they have the effect of being clearly distinguishable.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged cross-sectional view of the endless band used in carrying out the present invention, FIG. 2 is a partially plan view, FIG. 3 is a front view of the endless band in use, and FIG. 4 is a block diagram. FIG. 5 is a partially enlarged cross-sectional view of another embodiment of the endless band, and FIG. 6 is a partially enlarged cross-sectional view showing the relationship between the projecting piece and the object. 1... Base belt 2... Micro sphere 3...
・Transparent synthetic resin coating 4...Belt 5...Belt conveyor 6...Light source 7...Camera
9... Clam 14... Photographer 15...
・Setting device 16...Comparator 20...Protrusion piece Fig. 3 Fig. 4

Claims (1)

[Scope of Claims] 1. An object is placed on an endless band with specular or retroreflective properties, and light is projected from above, and the object and the endless band are distinguished based on the amount of reflected light. 2. An automatic object sorting method 2 characterized by measuring an area and sorting based on this flat area. 3. An automatic object sorting method 3 according to claim 1, characterized in that the object is sorted by comparing its reflection level with a set value. 4. The automatic object sorting method according to claim 1, wherein the reflective property is imparted by attaching micro transparent spheres. The object automatic sorting method according to claim 1, wherein the specular reflective property is imparted by providing an aluminum layer.