JPS5912339A - Method and apparatus for detecting part including large amount of water - Google Patents

Abstract

PURPOSE:To ensure the easy detection of the part wherein the rate of water content is high, by obtaining the dose of thermal infrared rays which are made to radiate from a heated object body, with respect to each part of said object body, and selecting the part where the dose is smaller than the reference. CONSTITUTION:A belt conveyer is placed at the downstream of a heating and drying process. Rubber crumb is spread over the conveyer in a layered shape. The dose of thermal infrared rays, which are made to radiate from the rubber crumb, is measured at each part on said crumb for every area having a unit area, with, e.g., 16mm.<2> as a unit. The crumb is heated at the heating and drying process, and made to radiate the thermal infrared rays corresponding to its surface temperature. At the part including a large amount of water, however, the surface temperature is low. The dose of the radiation of the thermal infrared rays is smaller than the other part, which is regarded as the reference. The part inicluding the large amount of water can be detected, by selecting the part, where the dose of the radiation of the thermal infrared rays is smaller than the reference, out of the part of said crumb.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for detecting the presence of a high moisture content in a target object.

Although it is generally undesirable for a high content of water to be present in the final product, water is actually used or the presence of water is required for the manufacture or processing of the product. There are many cases. In such cases, a drying process is usually performed to remove moisture from the object.

This drying may be difficult to achieve uniformly. For example, synthetic comb 9! Coagulate the rubber component in R violet or latex with water as the main dispersion medium to form coarse crumbs, or coagulate the crumbs by pressure etc. to form lumps or thick sheet veils. However, despite the drying process that is carried out in the production of crumbs or bales, areas with a high moisture content called wet spots may exist1. This will vary depending on the method of drying, but for example, drying using a hot air dryer will result in wet spots due to poor dispersion of crumbs on the pet. And the existence of this wet spot. Depending on the degree, it may cause trouble when the crumb or bale is used as a raw material.

Due to these circumstances, in the production of synthetic rubber. Examine whether there are wet spots on the burrs using crumb-like rubber that is fed through the drying process and then weighed and formed into bales, or bale-like rubber after forming. I try to eliminate areas where wet spots exist. and for detecting wet spots.

(1) Visual judgment (2) Direct measurement of moisture in the target object using an infrared absorption type moisture meter (8) Method using a moisture meter that takes advantage of the fact that the dielectric constant of water is different from the material of the target object, etc. methods are used.

However, these means have the following drawbacks.

(1) In visual detection, even if wet spots can be detected on the surface of the target object.
Unable to detect hidden wet spots,
It also has low certainty and reliability.

(2) Infrared absorption type moisture meter. This method irradiates the target object with infrared rays and detects differences in the degree of absorption of infrared rays due to differences in moisture content. If the surface condition of the target object is not constant, the degree of diffuse reflection of infrared rays by the surface will vary considerably, resulting in a large measurement error, and the degree of infrared absorption will vary depending on the shave quality of the target object, so it may vary depending on the material. As a result, the measurement results are unreliable because additional calibration is required.

(8) Moisture meters that focus on the difference in dielectric constant have the ability to change the capacitance between the electrode plates depending on the amount of moisture contained in the object when the object passes between the electrode plates facing each other. It is intended to detect. Changes in the thickness of the target object in the direction between the electrode plates directly affect the measurement results, making it impossible to perform highly reliable detection. Moreover, the measurement results are based on the water content contained in the entire target object, and it is particularly difficult to detect parts with a higher water content than others.The present invention solves the above drawbacks of the conventional method. It was completed as a result of intensive research to solve the problem, and its purpose is to detect parts of a target object that have a high moisture content (hereinafter referred to as ``high moisture content parts''). The object of the present invention is to provide a method that can be achieved extremely easily and reliably with high reliability.

Another object of the present invention is to provide an apparatus that can reliably detect a high moisture content part of a target object. Furthermore, it is an object of the present invention to provide a device capable of evaluating the condition and providing the information.

The method of detecting a high moisture content area according to the present invention is characterized in that the dose of thermal infrared rays emitted from a heated target object is determined for each part of the target object. The purpose is to select areas where the dose is smaller than the standard.

The high moisture content detection device according to the present invention is characterized by an infrared sensor and receiving thermal image information based on the surface temperature of each portion of a heated target object obtained by the infrared sensor.

and a high moisture content portion determination mechanism that determines whether the surface temperature of each portion is below a reference value.

Hereinafter, five embodiments of the present invention will be described in which a high water content portion is detected using a rubber crumb as a target object in the production of synthetic rubber.

In the present invention, for example, the dose of thermal infrared rays emitted from the crumbs spread out in layers on a belt conveyor located downstream of the heating drying process.

Each portion of the crumb is measured for each area of unit area, for example, 16111+2. Here's the crumb.

It is heated during the drying process and emits thermal infrared rays corresponding to its surface temperature, but in areas with high moisture content, that is, areas where wet spots exist, heat is taken away as latent heat of vaporization of moisture. Because of this, its surface temperature is low.

The dose of Z thermal infrared rays radiated from this part is smaller than this standard when other parts are used as a standard, or when a normal case known from experience is used as a standard. Therefore, by selecting a portion of the crumb for which the dose of radiant heat infrared rays is smaller than the standard, it is known that a wet spot exists in that portion, and the wet spot can be detected after all.

Therefore, in the present invention, in order to detect a high moisture content area by measuring the dose of thermal infrared rays emitted from the target object, the surface condition of the target object and the position of the target object, that is, the measurement part and the target The size or variation of the distance to the object does not directly affect the measurement result, therefore easily and reliably.

Wet spot detection can be achieved with high reliability. When the target object is heated and has a temperature higher than the ambient temperature, there will be a clear difference in the amount of radiated heat and infrared rays between areas where wet spots exist and areas where there are no wet spots, so detection can also be done from this point of view. The results will be more reliable. In the present invention, it is necessary that the target object be at a temperature higher than the ambient temperature.

For example, when there is a process of heating for drying, the object sent out from that process can be used as it is to be measured by radiant heat infrared rays, so there is no need to perform heating again when applying the present invention. It is extremely advantageous for detecting crumbs from the drying process in the production of synthetic beams or wet spots on bales formed by molding the crumbs.

Figure 1 is a system diagram of a specific device for detecting wet spots by applying the above-mentioned method to crumbs in the production of synthetic rubber. The belt conveyor conveying the 81-volume device is shown. An infrared camera 2 is installed whose viewing area covers the entire width of a predetermined length section of the belt conveyor 1. A thermal image signal for the crumb layer within the viewing area A is guided to a signal converter 8.

This signal converter 8 sequentially samples thermal image signals in all unit areas obtained by dividing the viewing area A into a plurality of units in the horizontal and vertical directions, and converts the signals into digital signals.

Therefore, this digitally converted signal is obtained by the number of points per unit area, that is, the number of points determined by (number of horizontal divisions) x (number of vertical divisions) per viewing area A, and the signal at each point is determined by the completion of digital conversion. Each time, it is sent to the temperature distribution calculation unit 4 which has a digital memory. Here,
The area of a unit area corresponding to one digital signal is determined by the distance between the infrared camera and the crumb layer, the optical performance of the infrared camera, and the number of horizontal and vertical divisions. It is considered to be a degree.

In this way, when digital signals are obtained for all unit areas, a numerical value corresponding to the maximum temperature value of the surface temperature to be determined as a wet spot, which is set in the wet spot determination reference level setting device 6, The temperature distribution calculation unit 4 compares the digital data of all unit areas stored in the digital memory, and the background processing unit 5 counts the number of digital data that is less than the set data, and the other data is delete. The count value in the background processing unit 5 directly corresponds to the area of the wet spot, and therefore it depends on the presence or absence of the counted data.
It is detected whether there are wet spots in the crumb layer within.

However, when determining the size of a wet spot using only the above configuration, it is possible to determine the size of a wet spot by changing the distance between the 9 crumb layer and the infrared camera 2, or by changing the number of horizontal and vertical divisions of the viewing area A. By changing the area of the unit area corresponding to one digital signal, it costs 80% and 1[If you try to detect only large wet spots.

The data becomes coarse, leading to a decrease in accuracy.

Therefore, in this device, a wet spot determination unit 7 is provided in order to determine the size of a wet spot without changing the area of a unit area corresponding to one disotic signal once determined. Shi, background processing unit 5? ? It is determined by BIn whether or not there is a wet spot distribution whose area is equal to or larger than the allowable area set by the suitability determination reference area setting unit 8 in the added wet spot distribution data.

For example, the following method is effective for determining the presence or absence of a wet spot of a certain area or more. First.

The background processing unit 5 converts the wet-spotted digital signal into a digital signal of "1" and other signals of "10" (hereinafter, this process is referred to as "binarization"). The number of divisions of the visual field A in the horizontal direction]1. Assuming n in the vertical direction, m x n digital data are obtained, and as a result of converting them into two binarized signals, a set of binarized signals of a total of +n x n pieces of 10'' or ``l'' is obtained.

From this set of Ill ×n fi−j binary signals,
For example, a subset of the z-valued signal related to a set of unit areas of 3 vertically and 8 horizontally is set by the standard area setting unit 8 for determining suitability, and if there is a value of "1" in this subset, 9 If there are 3 unit areas, there will be a wet spot with an area equal to or larger than the set of 8 unit areas vertically and 3 units horizontally. Then, in nlXn binary signals. Vertical 8
It is sufficient to investigate all subsets of the set of 8 unit areas.

As a result of the above calculation process, if there is a wet spot larger than the set reference area, an alarm signal will be issued, or the total area of wet spots larger than the reference area will be calculated and the result will be recorded in the record Mi9. Thus, with this device, it is possible to not only detect whether or not wet spots are present in the crumb layer of the targeted area, but also to detect how many wet spots are present. Therefore, the method according to the invention described above can be achieved automatically and the desired wet spot can be detected in a short time and with high reliability. Furthermore, the wet spot determination unit 7 determines whether or not the crumb layer in the specific section is unusable as a whole due to the presence of wet spots of a certain area or more. When it becomes unusable, this fact is reported by the recorder 9 or by a warning signal.

The crumb layer can be removed through the normal processing route, and only good crumbs can be sent to the next process. Alternatively, by simultaneously obtaining a signal from the wet spot determination unit 7 for specifying an area where it has been determined that a wet spot of a certain area or more exists, the crumb layer portion belonging to the area can be removed, It becomes possible to eliminate only defective crumbs. In general, the presence of wet spots in crumbs is not completely unacceptable, and if the proportion of wet spots is small, the presence of wet spots does not pose any problem in actual use.
Providing the wet spot determining unit 7 as described above to determine the suitability of crumbs has extremely important economic significance.

In the above, if the crumb layer on the belt conveyor 1 becomes uneven, the bare surface of the belt conveyor 1 may be exposed to the infrared camera 2. Since the surface temperature of the belt conveyor 1 is usually lower than the temperature of the wet spot, an erroneous determination will be made. Therefore, as shown in FIG. , is converted into a digital signal by a signal converter 12 similar to the signal converter 8, and this dizotal signal is guided to the background processing unit 5, and is converted into a visual field A of the infrared camera 2.
It is desirable to extract data above the reference level for wet spot determination from the digital data of the thermal signal and then delete data below the surface temperature.

In the above implementation row, the crumb item 4'4t is different.

Although the temperature of the crumbs from the drying process is slightly different, this can be easily dealt with by changing the reference level for determination using the reference level setting device 6 for determining wet spots.

As described above, regarding the crumb layer on the belt conveyor 1 in a specific section within the field of view of the infrared camera 2,
The suitability of the wet spot crumb layer is determined. These actions. The time required for the crumbs carried by the belt conveyor 1 to pass through the viewing area A of the infrared camera 2. Or by doing it periodically, with one period having a shorter period of time. It is possible to perform the desired detection and judgment for every crumb, especially if the cycle time is shortened so that the same crumb part is detected and judged twice or more. This is preferable because the reliability of the results obtained is very high.

In the above example, an infrared camera was used as the 5 infrared sensor. If the object is moving, it is not necessary to capture it as a surface; it is also possible to capture it as a straight line perpendicular to the direction of movement of the object, and process the signal by sampling at points along this straight line. Yes, it is possible. Above, I explained the case where the target object is crumbs from the drying process in the production of synthetic rubber.

In the present invention, there are no restrictions on the target object. Of course, it can also be applied to other objects.

In particular, for objects undergoing heat drying process, the degree of drying can be monitored.

This method is advantageous because it does not require a separate heating process for detecting high moisture content areas. As in the embodiment, it is suitable for detecting wet spots in synthetic rubber crumbs or bales.

As detailed above, according to the present invention, there is provided a method that can easily and reliably detect the presence or absence of a high moisture content portion in a target object, and a method that uses this method. It is possible to provide a device that can detect a moisture-containing part of a field, further evaluate its condition, and obtain information about it.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an example of an apparatus for carrying out the method for detecting a high moisture content portion of the present invention. 1... Belt conveyor 2... Infrared camera 8, 1
2...Signal converter 4...Temperature distribution gtN unit 5...Background processing unit 6...Wet spot determination reference level setter 7.
... Wet spot judgment unit 8 ... Standard area setting unit for suitability judgment 9 ... Recorder 11.
...Temperature sensor 18

Claims (1)

[Claims] 1) The dose of thermal infrared rays emitted from a heated target object is determined for each part of the target object. A method for detecting areas with high moisture content, characterized by selecting areas where the dose is smaller than a standard. 2) Infrared sensor and obtained by this infrared sensor. It is characterized by comprising a high moisture content portion determination mechanism that receives thermal image information based on the surface temperature of each portion of the heated target object and determines whether the surface temperature of each portion is below a reference temperature. 8) An infrared sensor, a signal converter that converts the thermal image information obtained by the infrared sensor based on the surface temperature of each part of the heated target object into a digital signal, a temperature distribution information creation unit that receives signals from a signal converter and creates temperature distribution information based on the surface temperature of the target object; A high moisture content portion determination unit extracts temperature distribution information, and the temperature distribution information extracted by the high moisture content portion determination unit determines whether the area ratio of the high moisture content portion of the target object is below the allowable standard ratio. 3. The high moisture content portion detection device according to claim 2, further comprising a target object suitability determination mechanism for determining whether or not there is a target object.