JPH05172528A - Method for measuring size of material - Google Patents

Abstract

PURPOSE:To obtain the method for measuring the size of a material when the sizes are controlled in the production, shipment, acceptance and the like of rocks, ores and other materials. CONSTITUTION:A material is photographed by using a photographing device. The image signal from the photographing device is sent into an image processing device. The image is cut away by a preset width (t) from the peripheral part of every image A of the material with the image processing device. The cutting is repeated. The number of cuttings until the image of the product disappears is made to be the size of the material. The size is outputted for every material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the dimensions of rocks, ores, and other articles in the case of performing dimension control such as production, shipping and acceptance.

[0002]

2. Description of the Related Art For example, when shipping or receiving rocks, ores, or other articles, it is necessary to confirm whether or not they have predetermined dimensions, or to select a sieving machine for sorting ores or the like. In order to detect the breakage of the net, it is necessary to measure the size of the ore or the like that has passed through the net and take measures as the breakage of the net when this size exceeds the set value. For such dimension management,
Conventionally, the following measures have been taken as a method for measuring the dimensions of an article.

A. A method in which a person visually monitors b. Method of inferring dimensions from the sound of an article hitting an iron plate c. A method of actually sorting articles using a mechanical vibrating screen d. Method of measuring maximum length, area, etc. by image processing

[0004]

SUMMARY OF THE INVENTION Method a. Has the drawback of low reproducibility and large error due to fatigue.

Method b. Is a large error, noise is generated, failure due to wear, etc.
There are drawbacks such as the possibility of damage to the article.

Method c. Is a measurement time,
There are drawbacks such as failure due to wear.

The above method d. Is unsuitable for inspection and replacement of mechanical vibrating screens because it has little correlation with mechanical vibrating screens depending on the shape of the article.

An object of the present invention is to provide a measuring method which eliminates the above-mentioned drawbacks in the conventional article dimension measuring method.

[0009]

According to the present invention, an object is photographed by a photographing device, and an image signal from the photographing device is sent to an image processing device. This is solved by repeating the deletion of the image for each image from its periphery with a predetermined width, and outputting the number of deletions until there are no images of the product as the size of the product for each product.

[0010]

With respect to each image of the article displayed on the display screen of the image monitor, the image is repeatedly deleted from the periphery with a predetermined width, and the number of deletions until the image of the article disappears is defined as the dimension of the article.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show an example in which the present invention is applied to detect the breakage of the net of a sieving machine for sorting according to the size of ore or the like (hereinafter referred to as stone). Hereinafter, the present invention will be described with reference to these drawings, but the present invention is not limited thereto.

In FIG. 1, a stone 1 carried out from a crusher (not shown) or other processing device falls on a net 2 of a sieving machine, and is subjected to size selection by the net 2. Stones 1a larger than the mesh openings fall on the mesh discharge conveyor 3 without passing through the mesh, and stones 1b smaller than the mesh openings pass through the mesh and under the mesh discharge conveyor 4 It drops down and is discharged.

The stone 1b on the under-mesh discharge conveyor 4 is an ITV.
The image is taken by the photographing device 5 such as a surveillance camera or a video camera, and the signal is sent to the image processing device 6, where the size of each stone is measured. An image monitor 7 for inspection and adjustment can be installed in the image processing device 6. The image monitor 7 can be used not only for inspection and adjustment, but also for monitoring the stones 1b on the below-mesh discharge conveyor 4 if necessary. 7a is a display screen of the image monitor 7.

The dimensions of the individual stones measured by the image processing device 6 are compared with the dimensions preset by the setting device in the arithmetic unit 8. If there is a stone larger than a preset size, the net 2 is broken and a signal is sent to the alarm device 9 to issue an alarm. The setting value input may be set by a person in advance, or the setting may be changed by the arithmetic unit 8 itself by some learning function.

A display screen 7a of the image monitor 7 shown in FIG.
The images A, B of several stones on the net discharge conveyor 4 are
C and D are displayed. Of these, only the image A of the stone is shown in FIG. 3 to describe the dimension measuring method in the image processing apparatus 6, but the images B, C and D of the other stones displayed on the display screen 7a are also described. The size is measured for each image.

In FIG. 3, the image processing apparatus 6 deletes a stone image A on the display screen 7a of the image monitor 7 with a predetermined width t, for example, a width corresponding to 10 mm, and a new stone image A is displayed. Get ' Image A'of this newly obtained stone
Again with the same width t, and a new stone image A ”
To get This operation is repeated, and the image a of the minimum stone is obtained by repeating the deletion of N-1 times. If the image is eliminated by the N-th deletion, the number of times N is set as the size of the stone. This dimension measurement is also performed on the images B, C, and D of other stones.

The value of the deletion width t can be appropriately determined depending on the size, shape, distribution state, etc. of the stone image.

[0018]

EFFECTS OF THE INVENTION Since the method for measuring the size of an article according to the present invention is non-contact, there is no abrasion of the contact portion with the article or damage to the article, and even if the article has an irregular shape such as ore, The dimensions can be measured reliably. Therefore, it has a large correlation with the mechanical vibrating screen and is suitable for inspection and replacement of the vibrating screen.

Further, in detecting the breakage of the net such as a sieving machine for sorting by size, the measured value obtained as described above and the maximum value that can be passed when the preset net is not broken. The size of the article is compared, and when the measured value is larger than the set value, it is possible to judge that the net is broken and issue an alarm. Furthermore, it is possible to control the mechanical settings of the crusher, which has great industrial value.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a network breakage detection device of a sieving machine to which the measuring method according to the present invention is applied.

2 is a display screen of an image monitor of the apparatus shown in FIG.

FIG. 3 is an explanatory diagram of a stone size measuring method according to the present invention.

[Explanation of symbols]

 1 stone 1a stone that did not pass through the net 1b stone that passed through the net 2 net 5 shooting device 6 image processing device 8 computing device 9 alarm device A, B, C, D stone image t width of deletion

Claims (1)

[Claims] 1. A method for measuring the dimensions of an article in the case of performing dimension management such as production, shipping, and acceptance of the article, wherein the article is photographed by using a photographing device and an image signal from the photographing device is sent to an image processing device. , This image processing device repeatedly deletes the image with a predetermined width from the periphery of each image of the article,
A dimension measuring method characterized in that the number of deletions until the image of an article disappears is output as the dimension of each article for each article.