JPH05196587A - Kind discrimination method and device of resin - Google Patents

Abstract

PURPOSE:To exactly discriminate the kinds of resin of resin products without any error even by a person having no knowledge and experience in the field by efficiently utilizing a characteristic the heat deformation temperature of the resin takes a respective specific value according to the kind. CONSTITUTION:A part of the surface of a resin product A is heated with a heater 1 and the temperature accompanying the heating at time when heat deformation is produced is detected with the use of a sensor 5. The detection temperature is compared with the heat deformation temperature of a plurality of kinds of resin previously stored in a memory 10 and a discrimination signal (b) for indicating the resin having heat deformation temperature nearest to the detection temperature is output. On the basis of the discrimination signal (b), for instance, the kind name of the resin of a heating resin product is shown on a display 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin that is applied when, for example, when collecting and reusing resin products mixed in wastes, the products are sorted according to the type of resin and then treated. The present invention relates to a type discriminating method and a resin type discriminating apparatus used for carrying out the method.

[0002]

2. Description of the Related Art For example, as a method for discriminating the type of resin of resin product waste, there are known methods as follows.
There are two main types. One is a method in which after the end consumer uses the product, the products are sorted according to type, sorted and discarded. In order to respond to such type discrimination by the end consumer, the manufacturer of the resin product is devised to display the number or symbol indicating the type of resin on the surface of the product concerned where it is easy to see. .. The other one is a method in which a person who has sufficient knowledge and experience in determining the type of resin sorts the mixed resin products by visual inspection.

[0003]

Among the above-mentioned conventional type determination methods, the former type of determination by the end consumer is as follows:
Since it is not possible to check the type discrimination error, if an old person or child mistakenly discards a resin product, it will be collected as it is and will be carried into the reuse process, causing various troubles. There was a possibility to invite. The latter method, in which a person with specialized knowledge and experience visually inspects and sorts, requires a large number of specialists to cope with the increasing amount of waste, and it is difficult to secure such specialists. It is not practical from the standpoint of the situation. In addition, even if the work is done by a specialist, if the work is continued for a long time, it is easy to make an error in the discrimination of the types, and like the former method, avoid various troubles in the post-treatment process. I can't.

As described above, since the conventional type discriminating method has a limit in practical use, the type is not discriminated, and an example of incineration or chemical treatment with a plurality of types of resins mixed is performed. Also seen. However, in the case of such mixed treatment, when performing continuous treatment for a long time, for example, in the case of incineration treatment, an incineration facility that can withstand the combustion heat of the resin having the highest calorific value among the plurality of resins is required. In addition, in the case of chemical treatment, the equipment and operation are extremely irrational and uneconomical, such as the equipment capable of treating the most difficult type of resin. If this point is not taken into consideration, another problem arises in that the prescribed processing cannot be performed, or the equipment is damaged.

The present invention has been made in view of the above circumstances, and makes effective use of the characteristics of resins to accurately determine the types of a plurality of resins without requiring specialized knowledge or experience. It is an object of the present invention to provide a resin type determination method and apparatus capable of efficiently determining the type.

[0006]

In order to achieve the above object, the method of determining the type of resin according to the invention of claim 1 of this application is to monitor the presence or absence of thermal deformation while heating the resin product, The type of resin is determined from the temperature at which thermal deformation occurs.

Further, in the resin type discriminating apparatus according to the second aspect of the present invention, a heater for heating at least a part of the surface of the resin product, a temperature sensor for detecting the temperature of the heated portion by the heater, and a plurality of types. A memory that stores the heat distortion temperature of the resin is compared with the heat distortion temperature from this memory and the temperature detected by the temperature sensor, and a discrimination signal indicating the resin having the heat distortion temperature closest to the detected temperature is output. It is provided with a discriminating means and a control means for turning off the heater in response to a command signal synchronized with the occurrence of thermal deformation of the heated portion and driving the discriminating means.

Further, in the resin type discriminating apparatus according to the invention of claim 3, a heating furnace for heating the resin product to a predetermined temperature corresponding to a heat deformation temperature of a specific type, and the resin product are sequentially fed into the heating furnace. A transfer device, a discharge device for discharging the heated resin product from the transfer device to the outside, first and second photographing devices for photographing the resin product before and after heating in the heating furnace, and both photographing devices Image comparison means that outputs a detection signal when a difference of a predetermined value or more is detected, and the discharge device is driven in response to the detection signal to discharge the resin product that has been thermally deformed. Emission control means is provided.

[0009]

According to the method of determining the type of resin according to the invention of claim 1, when the resin product is heated, thermal deformation occurs,
The temperature at which heat is deformed shows a unique value depending on the type of resin.By using such characteristics to determine the type, the type of resin can be determined without specialized knowledge or experience. There is no doubt that it can be accurately identified.

Further, according to the resin type determining device of the second aspect of the present invention, when at least a part of the surface of the resin product is heated by the heater, thermal deformation occurs in the heated part, and the heated part at this time. Temperature is detected by the temperature sensor, and the detected temperature is compared with the heat deformation temperatures of a plurality of types of resins preset and stored in the memory to indicate the resin having the heat deformation temperature closest to the detected temperature. The discrimination signal is output. Therefore, the type of resin of the resin product can be accurately determined. Since the heater is turned off and the heating is finished by a command signal synchronized with the occurrence of thermal deformation, for example, a command signal generated by a switch operation of the operator, there is no possibility that the resin is accidentally overheated and erroneous determination is made. ..

Further, according to the resin type determining device of the third aspect of the present invention, when the resin products are sequentially fed into the heating furnace through the transfer device, the resin products are heated to a predetermined temperature in the heating furnace and are heated. Deform. An image of the resin product after heating and an image of the resin product before heating are respectively photographed by the second and first photographing devices, both images are compared, and if there is a difference more than a predetermined value, a detection signal is given. The resin product, which has been output and has undergone thermal deformation in the heated resin product in response to the detection signal, is discharged from the transfer device to the outside by driving the discharging device. In this way, by simply sending the resin product to the heating furnace via the transfer device, the above-described operations can be performed automatically, and the process from the type determination of the resin to the sorting and discharging can be fully automated.

[0012]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a configuration diagram showing an outline of a manual type of resin type discriminating apparatus used for applying the resin type discriminating method of the present invention. In the figure, reference numeral 1 is a heater, which is a probe 2 extended from the portable case 2 to one side.
It is installed in the tip of A and is a commercial AC 100.
It is equipped with a power supply unit 3 connected by inserting a plug into a V outlet and is turned on / off and reset by a switch 4 mounted on the surface of the portable case 2. The heater 1 is set to be capable of raising the temperature up to about 500 ° C., and is pressed against a part of the surface of the resin product A to heat that part.

Reference numeral 5 denotes a thermocouple as a temperature sensor for detecting the temperature of the portion heated by the heater 1, which is embedded in the tip of the probe 2A, the detected temperature of which is passed through an amplifier 6 to be described later by comparison means. 7 is sent to the A / D converter 8, converted into a digital value by the A / D converter 8, and displayed on the temperature display section 9 formed on the surface of the portable case 2. Reference numeral 10 is a memory in which a plurality of types of resin names and their heat distortion temperatures are input and stored in advance. The heat distortion temperature from the memory 10 and the temperature detected from the thermocouple 5 are compared by the judging means 7, and the judgment signal b indicating the resin having the heat distortion temperature closest to the detected temperature is output. Based on b, the type name display section 12 formed on the surface of the portable case 2 displays the type name of the resin.

Reference numeral 13 is a control means interposed between the switch 4 and the power source section 3, and the switch 4 when the portion heated by the heater 1 on the surface of the resin product A is thermally deformed.
In response to the OFF signal (command signal), the heater 1 is turned off, and the internal circuit including the comparing means 7 is controlled to be continuously driven by the built-in storage battery 14.

Next, a discrimination method by the resin type discriminating device having the above construction will be described. First, when the operator presses the tip of the probe 2A against a part of the surface of the resin product A of which the type is unknown and turns on the switch 4 manually, electric power is supplied from the power supply unit 3 to the heater 1, and the heater 1 A part of the surface of the resin product A is heated. Along with this heating, when a part of the surface of the resin product A is melted and thermal deformation starts to occur, when the switch 4 is turned off by the manual operation of the operator, the command signal a which is the off signal is received. The control means 13 operates to turn off the heater 1 and
The internal circuits such as the determination unit 7, the A / D converter 8 and the memory 10 are continuously driven through the built-in storage battery 14. When the heater 1 is turned off, unexpected overheating of the resin product A is prevented.

During the above operation, the temperature of the heated portion on the surface of the resin product A is detected by the thermocouple 5. The detected temperature is amplified by the amplifier 6, one of which is A
After being converted into a digital quantity through the / D converter 8,
While being displayed as a digital value on the temperature display section 9, the other one is sent to the discriminating means 7. In the comparison means 7, the detected temperature and the heat deformation temperatures of a plurality of kinds of resins stored in the memory 10 are sequentially and automatically compared, and the resin having the heat deformation temperature closest to the detected temperature is shown. The discrimination signal b is output. In response to this discrimination signal b, the resin name is displayed on the type name display section 12.
Therefore, the operator can know the resin type name of the resin product A by reading the resin name displayed on the type name display portion 12 after turning off the switch 4.
Accordingly, it is possible to sort into a plurality of types suitable for post-treatment.

When the above-mentioned resin type discrimination work is completed, by switching the switch 4 to the reset side, all the functions are reset to the initial state and used for the next type discrimination of the resin product A. It

FIG. 2 is a block diagram showing the outline of another embodiment of the resin type discriminating apparatus used for applying the resin type discriminating method of the present invention. Since it is the same as the resin type determination device of the embodiment shown in FIG. 1, the same reference numerals are given to corresponding portions, detailed description thereof will be omitted, and only different points will be described in detail.

In FIG. 2, at the tip of the probe 2A extending from the portable case 2, there is formed a flange-shaped backing plate portion 2B which can come into close contact with the surface of the resin product A, and A spring 15 applies an outward elastic force to the heater 1 and the thermocouple 5 housed in the probe 2A. Reference numeral 16 denotes a movement detection actuator such as a micro switch that detects that the surface of the resin product A is softened by the heating of the heater 1 and the heater 1 is moved outward by a certain amount due to the elastic force of the spring 15. An operation piece 17 for operating the actuator 16 is provided to project laterally from the heater 1, and the control means 1 uses the operation signal of the actuator 16 as a command signal a.
3, the heater 1 is turned off and the discriminating means 7 is driven similarly to the above embodiment.

According to the resin type discriminating apparatus having the structure shown in FIG. 2, the surface of the resin product A is removed by heating the heater 1 by using it in the same manner as in the embodiment of FIG. When the heater 1 is softened and deformed, and as a result, the heater 1 moves by a certain amount by the elastic force of the spring 15, the actuator 16 automatically detects the movement and operates the control means 13. Therefore, the operator only has to turn on the switch 4 in the initial stage, and the work of determining the type of the predetermined resin becomes easier.

FIG. 3 is a block diagram showing the outline of another embodiment of the resin type discriminating apparatus used for applying the resin type discriminating method of the present invention. Paper and the like have the function of sorting and discharging only resin products that have already been separated in a separate process by resin type.

In FIG. 3, reference numerals 21A to 21G denote resin products of specific types of resins, for example, polyethylene, polypropylene, nylon 6, polyurethane, polystyrene, epoxy resin, PTFE (polytetrafluoroethylene), PET (polyethylene terephthalate). 8
A predetermined temperature set corresponding to the heat distortion temperature of each type of resin (52 ° C., 60% if stated for each type of resin)
It is a plurality of hot air circulation type heating furnaces for heating to 7 ° C., 75 ° C., 90 ° C., 105 ° C., 115 ° C., 130 ° C.).
These heating furnaces 21A to 21G are partitioned by providing partition walls 22A to 22F between adjacent ones, and the heating furnaces 21A to 21G are arranged linearly in order from one having a low heating temperature (heat deformation temperature) to one having a high heating temperature. Each of these heating furnaces 21A to 21G has a temperature sensor 23A to 23G for detecting the temperature inside the furnace corresponding to the respective heating temperature, and each of these temperature sensors 23A.
The temperature control blowers 24A to 24G for adjusting the temperature in response to the signals from 23G, the filter (not shown) for cleaning the hot air discharged from the furnace, and the like are provided.

Reference numeral 25 denotes the above-mentioned plurality of heating furnaces 21A to 21G
In a series of states erected through the inside of, a resin product transfer device consisting of, for example, a heat resistant belt conveyor,
The resin product A placed here is placed in each of the heating furnaces 21A to 21A.
Send to 1G sequentially. A centralized management control device 31 is provided to collectively control the transfer device 25 and the temperature control fans 24A to 24G.

Discharge devices 26A to 26G for discharging the resin product A from the transfer device 25 to the outside are provided at the outlets of the heating furnaces 21A to 21G, respectively. These discharge devices 26A to 26G are discharge ports 26a to 26g of a size sufficient to discharge the resin product A and discharge ports 26a to 26g of the resin product A placed on the transfer device 25.
A payout arm 26a that operates to pay out toward g
1 to 26g1.

The first and second three-dimensional images of the resin product A before and after heating in the heating furnaces 21A to 21G are taken on the ceilings of the entrances and exits of the heating furnaces 21A to 21G. The video camera 27
A-27H and 28A-28H are installed. Then, the first and second heating furnaces 21A to 21G are provided.
Video cameras 27A, 28A, 27B, 28B, ...
.. are provided with image comparison means 29A to 29H for comparing three-dimensional images by 27H and 28H and outputting a detection signal when a difference of a predetermined value or more is detected, and the detection signals from these image comparison means 29A to 29H. In response to the above, one of the corresponding discharging devices of the discharging devices 26A to 26G is selected.
Discharge control means 30A to 30G for driving the resin product A that has been thermally deformed is provided.

Next, a method of discriminating (selecting) by the resin type discriminating apparatus having the above construction will be described. With the operation of the transfer device 25, the resin product A placed on the transfer device 25 is sequentially transferred in the heating furnaces 21A to 21G at a constant speed. During such transfer, each heating furnace 21A-2
Video camera 27A-27H at the entrance of 1G is resin product A
The three-dimensional image before heating is captured, and the image is input to one of the image comparison units 29A to 29H. Then, the resin product A passing through each of the heating furnaces 21A to 21G is heated to the set temperature corresponding to the peculiar heat deformation temperature, and is deformed when the peculiar heat deformation temperature is reached, The three-dimensional image of the resin product A after the heating deformation is a video camera 28A to 28H at the exit of each heating furnace 21A to 21G.
The image is photographed by the image comparison means 29A.
˜29H, where it is compared to the 3D image before heating.

When it is detected from the comparison results of the image comparison means 29A to 29H that there is a predetermined difference or more between the images, that is, that there is thermal deformation, based on the detection signal, The discharge control means 30A to 30H are activated to drive the discharge arms 26a1 to 26g1 of the discharge devices 26A to 26G of the heating furnace, and discharge the resin product A from the transfer device 25 to the outside of the furnace via the discharge ports 26a to 26g. Let In this way, the discharged resin product A is a resin having a heat distortion temperature corresponding to the set temperature of the heating furnaces 21A to 21G. For example, the kind of resin of the resin product discharged from the heating furnace 21E set to 105 ° C. is polystyrene, and the heating furnace 2 set to 130 ° C.
The type of resin of resin products discharged from 1G is PTFE
(Polytetrafluoroethylene), and the type of resin of the resin product that has not been discharged until the end is PET (polyethylene terephthalate), which is carried out of the furnace while being mounted on the transfer device 25.

In the embodiment shown in FIG. 3, the partition walls 22A to 22A provided between the heating furnaces 21A to 21G are adjacent to each other.
A damper (not shown) is provided in the lower part of 22F, and the damper is closed except when the resin product is passing, so that unnecessary air flow is suppressed.
It is possible to accurately and efficiently adjust and maintain the internal temperature of 21G. Further, in order to absorb and separate the gas generated when the resin product is heated and deformed, each heating furnace 21A
It is desirable to attach a gas filtration device to ~ 21G.

Further, nylon 6 and polyurethane and polyvinyl chloride are difficult to distinguish because their heat distortion temperatures are in the same range. Therefore, those heating furnaces 2
It is preferable to add chlorine sensors to 1C and 21D, respectively, to detect chlorine gas generated during thermal deformation of polyvinyl chloride to supplement the discrimination function.

Further, in the embodiment shown in FIG. 3, the video cameras 27A to 27H and 28A to 28H and the transfer device 2 are used.
The timing adjustment with 5, that is, the tracking can be easily realized by keeping the transfer speed of the transfer device 25 constant. That is, the video camera 27A on the entrance side
The same resin product A is accurately tracked by comparing the three-dimensional images taken by 27H and the exit side video cameras 28A to 28H by the image comparison means 29A to 29H with a certain time difference corresponding to the transfer speed. while doing,
The thermal deformation can be detected.

In the embodiment, eight kinds of resins can be selected, but the number of kinds of resins that can be selected can be adjusted by increasing or decreasing the number of heating furnaces.

Needless to say, the resin products to be subjected to type discrimination are not limited to the wastes as in the above-mentioned embodiments, but all resin products of unknown material. Further, in the embodiment of FIG. 1, the type name of the resin is displayed in the type name display section 1.
Although it is displayed on the display 2 and is visually observed, a voice alarm device for notifying the type name by voice may be provided unlike this.

[0033]

As described above, according to the invention of claim 1 of this application, the heat distortion temperature generated when a resin product is heated exhibits a unique value depending on the type of resin. By performing the determination, it is possible to accurately and accurately determine the type of resin without any specialized knowledge or experience.

Further, according to the invention of claim 2, the kind of resin of the resin product can be accurately determined by a very simple operation of heating at least a part of the surface of the resin product by the heater.
In addition, it is possible to make a quick discrimination, and the discrimination accuracy can be stably maintained even during continuous work for a long time.

Further, according to the third aspect of the present invention, heating the resin product, the resin product before heating and the resin product after heating are simply set by placing the resin product in which a plurality of types are mixed on the transfer device. It is possible to fully automate a series of operations such as determining the resin type by comparing the image with the resin product, sorting the resin products after the determination, and discharging each sorted resin product. As a result, it is possible to improve the processing efficiency of the resin waste and significantly improve the economical efficiency of the processing equipment.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an outline of an embodiment of a type discriminating apparatus to which a resin type discriminating method according to the present invention is applied.

FIG. 2 is a configuration diagram showing an outline of another embodiment of the present invention.

FIG. 3 is a configuration diagram showing an outline of another embodiment of the present invention.

[Explanation of symbols]

1 ... Heater, 4 ... Switch, 5 ... Thermocouple (temperature sensor), 7 ... Judgment means, 10 ... Memory, 11 ... Judgment means,
12 ... Resin type name display section, 13 ... Control means, 21A ...
21G ... Heating furnace, 25 ... Transfer device, 26A-26G ... Ejection device, 27A-27H, 28A-28H ... Video camera (shooting device), 29A-29H ... Image comparison means, 30
A to 30G ... Emission control means, A ... Resin product.

Claims (3)

[Claims] 1. A method for discriminating a plurality of types of resins, wherein the presence or absence of thermal deformation is monitored while heating a resin product, and the type of resin is discriminated from the temperature when the thermal deformation occurs. How to determine the type of resin. 2. A heater for heating at least a part of the surface of a resin product, a temperature sensor for detecting the temperature of a heated portion by the heater, a memory for storing heat deformation temperatures of a plurality of kinds of resins, and a memory for storing the temperature. Of the thermal deformation of the heating portion is synchronized with the determination means for comparing the thermal deformation temperature of the above-mentioned and the temperature detected by the temperature sensor and outputting a determination signal indicating the resin having the thermal deformation temperature closest to the detected temperature. Receiving the command signal, the heater is turned off, and the resin type discriminating apparatus is provided with control means for driving the discriminating means. 3. A heating furnace for heating a resin product to a predetermined temperature corresponding to a specific type of heat distortion temperature, a transfer device for sequentially feeding the resin product to the heating furnace, and a heated resin product from the transfer device. By comparing the images of the discharging device for discharging to the outside, the first and second photographing devices for photographing the resin product before and after heating in the heating furnace, and the above-mentioned photographing devices, a difference more than a predetermined value was detected. A resin type discriminating apparatus comprising: an image comparing unit that sometimes outputs a detection signal; and a discharge control unit that receives the detection signal and drives the discharging device to discharge the resin product that has undergone thermal deformation.