JP2003307505A - Noncontact inspection device and noncontact inspection method by thermography - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve failure rate detecting accuracy by removing influence by a surrounding environmental temperature change in a heat image pattern for acquiring the quality of fusion of an aluminum seal fused on a bottle opening part by using an infrared camera. <P>SOLUTION: A noncontact detecting device and its noncontact detecting method by a thermography are provided for determining the quality of a product by new image temperature data of correcting an environmental temperature change on infrared ray heat image temperature data Td acquired via the infrared camera 7 from above a cap 3 put on the aluminum seal 2 on the basis of environmental temperature data Tb acquired by a surrounding environmental temperature measuring temperature sensor 8 arranged in the vicinity of a measuring position. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact inspection device and a non-contact inspection method for a seal portion of a heat-sealed synthetic resin container in a non-contact state by thermography.

[0002]

2. Description of the Related Art Conventionally, a resin container (hereinafter referred to as a bottle) is filled with mayonnaise, tomato ketchup or the like, and an aluminum foil or the like is heat-sealed at the opening of the bottle,
An inspection device for analyzing and displaying an annular thermal image and performing a heat seal inspection using an infrared camera for thermography with the cap closed is disclosed in, for example, Japanese Patent Laid-Open No. 10-2789.
It is disclosed and known in Japanese Patent Laid-Open No. 10-318955 and Japanese Patent Laid-Open No. 10-318955.

In the above-mentioned Japanese Patent Laid-Open No. 10-278910, if a defective product is judged when the temperature obtained when an infrared camera scans the heating seal line is above or below a set value, it is determined that the product is defective. If the temperature distribution is not uniform like the high temperature region and the low temperature region, and if it exceeds the predetermined judgment value in the low frequency region, it will be defective and it will not be possible to detect it. Determine the value and the judgment value of the defective product, compare and count the detection signal of the object by infrared camera scanning with the judgment value of the abnormal temperature level,
There is disclosed a product inspection apparatus by thermography that compares the count value with a determination value of a defective product to determine a defective product.

Further, in JP-A-10-318955, as shown in FIG. 7, a bolt 1 is filled with contents such as mayonnaise, and an inner lid (aluminum seal) made of at least an aluminum foil and a synthetic resin molding member. 2 is sealed with aluminum foil by high frequency induction heating, and the infrared thermal image pattern 4 obtained from the upper surface of the outer lid (cap) 3 is processed and analyzed,
A non-contact inspection method for high-frequency aluminum seals is disclosed, which is designed to determine the joining state of the aluminum seals 2.

As a method for analyzing temperature distribution data from the infrared thermal image pattern 4 mentioned above, there are (1) abnormal temperature detection, (2) seal abnormal shape detection, (3) seal temperature distribution detection, and (4) seal temperature change rate detection. Has been shown off.

[0006]

In the data analysis method of the infrared thermal image pattern 4 having the above-mentioned conventional structure, the quality of the fusion of the aluminum seal 3 is determined to be a fixed value or an infrared thermal image at a constant measurement environment temperature. Since the pattern 4 is used as the criterion, the following problems occur. (1) Since the heat container of the cap 3 for tightening the aluminum seal 2 mounted on the bottle 1 is small, the abnormal high temperature value fluctuates when the measurement environment fluctuates. (2) The abnormal shape of the seal portion also changes under the same conditions. (3) The seal temperature distribution also changes under the same conditions. (4) The seal temperature change rate also changes under the same conditions.

Now, with reference to FIGS. 8A to 8D, a pattern change when the environmental temperature of the infrared thermal image pattern acquired by the infrared camera changes will be considered.

8 (A) and 8 (C) are predetermined values (room temperature 25 ° C.)
Assuming that the infrared thermal image pattern is when the ambient temperature changes to ΔT (room temperature 20 ° C.), FIGS. 8B and 8D are temperature distributions along the line AA ′. 8 (A) (B)
Then, if the threshold value is Cs, the high temperature value ΔTa which is an abnormal temperature above a certain level changes to ΔTb in FIGS. 8C and 8D, and the inner and outer diameters of the concentric pattern of the seal portion and the temperature distribution width a
Also changes to b, and the rate of change of the seal temperature naturally changes.

The present invention has been made to solve the above problems. The problem to be solved by the present invention is that the defect detection rate in the aluminum seal adhesion defect determination changes even if the measurement temperature environment changes. The present invention provides a non-contact inspection device and a non-contact inspection method using thermography.

[0010]

According to a first aspect of the present invention, an annular opening portion of a resin container 1 is fused with a heat seal 2 to form an outer lid 3.
In the non-contact inspection device by thermography, which is configured to inspect the quality of adhesion of the heat seal 2 via
A thermal image acquisition means 10 for acquiring an annular thermal image on the heating seal 2 via an infrared camera 7 arranged on the outer lid 3 of the resin container 1, and a temperature arranged in the measurement environment of the resin container 1. An environmental temperature variation correction processing means 11 for performing variation correction processing with respect to the reference environmental temperature via the sensor 8 is provided, and based on the thermal image pattern data Td after the environmental temperature variation correction processing of the environmental temperature variation correction processing means 11. This is a non-contact inspection device by thermography, which is characterized by determining whether or not the heat seal 2 is adhered.

The second aspect of the present invention is designed so that the annular opening of the resin container 1 is sealed by high-frequency heating, the opening is fixed by the outer lid 3, and the adhesion of the seal 2 is inspected. In a non-contact inspection method using thermography, a thermal image acquisition step S ₂ for acquiring a circular thermal image on a seal via an infrared camera 7 arranged on the outer lid 3 of a resin container, and a resin image The thermal image pattern data after the environmental temperature fluctuation correction processing step is provided with an environmental temperature fluctuation correction processing step which is arranged in the measurement environment of the container 1 and performs a temperature fluctuation correction processing with the reference environmental temperature via the temperature sensor 8. This is a non-contact inspection method by thermography, which is characterized by determining whether or not the adhesion of the seal is based.

According to the non-contact inspection apparatus and the non-contact inspection method using thermography of the present invention, it is possible to improve the detection accuracy of defective products even if the temperature condition of the measurement environment changes. To be

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A non-contact detection device by thermography and a non-contact detection method thereof according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a flowchart of environmental temperature fluctuation correction processing of a non-contact detection method by thermography according to the present invention,
2 is a system diagram for performing product quality determination of the non-contact detection device by thermography of the present invention, FIG. 3 is a flow chart for product quality determination, and FIGS. 4 to 5 are explanatory diagrams of a determination method for quality determination. Is. Before explaining FIG. 1,
The overall configuration of the non-contact detection device and the non-contact detection method using thermography according to the present invention will be described with reference to FIGS. 2 and 3.

In FIG. 2, contents such as seasonings such as mayonnaise, dressing and tomato ketchup are filled in a resin container (bottle) 1 to be inspected, and the opening of the bottle 1 An aluminum seal 2 made of aluminum foil laminated with a heat-meltable resin film such as a polyethylene film is placed on the annular opening, and a synthetic resin cap 3 serving as an outer lid is screwed into the opening. By bringing the belt conveyor 5 onto the high-frequency induction heating device 6 and applying high-frequency induction heating, the aluminum seal 2 is heated by the eddy current, and the product fused in an annular shape at the opening of the bottle 1 is completed. .

Next, the bottle 1 is inserted into a non-contact detection device 27 by thermography in order to perform a 100% inspection as to whether or not the fusion has been performed in an annular shape on the opening of the aluminum seal 2.

When the bottle 1 moving on the belt conveyor 5 is detected by the position sensor 9, a timing signal Ts is output and the infrared camera 7 starts to pick up the image.
The thermal image temperature data Td is acquired from the upper side of the cap 3 of FIG. A temperature sensor 8 for detecting the ambient environment temperature is arranged near the infrared camera 7 to monitor the ambient environment temperature at the measurement position.

When the infrared camera 7 receives the timing signal Ts as the measurement start signal, the infrared camera 7 moves over the cap 3 as shown in FIG.
(A) AA '(horizontal) direction is sequentially subjected to line scanning or area scanning from the first scanning line of BB' (vertical) scanning lines and supplied to the thermal image acquisition means 10. .

In the thermal image acquisition means 10, binarization processing or the like is performed, and an aluminum seal 2 as shown in FIG. 4 (A) is fused in an annular shape to the opening of the bottle 1 and is attached to the surface of the cap 3. Although not shown, the transferred thermal image temperature data is displayed on a display device or the like.

The thermal image data Td acquired by the thermal image acquisition means 10 is supplied to the environmental temperature variation correction processing means 11, and the environmental temperature data Tb is supplied from the temperature sensor 8.

The environmental temperature fluctuation correction processing means 11 will be described later with reference to FIG.

The reference value 12 and the judgment value 13 are supplied to the overheating judgment processing means 14 of the environmental temperature fluctuation correction processing means 11.
Is overheated on the basis of the data stored in the memory, the non-defective product (OK) is supplied to the shape defect determination processing means 17 in the next stage, and the defective product (NG) is supplied via the defective product processing output means 25. The defective product processing unit 26 removes the product.

In the shape defect determination processing means 17, the reference value 15
And the reference value 15 and the judgment value 16 in which the judgment value 16 is stored
The shape defect determination processing is performed based on the data from the memory in which is stored. If OK, it is supplied to the defect defect determination processing unit 20 in the next stage, and if it is NG, the defective product processing unit 26 via the defective product processing output unit 25. The product is removed at.

In the defect / defect determination processing means 20, the reference value 18
Further, the overheat defect determination processing unit 23 performs overheat defect determination processing based on the data from the memory in which the determination value 19 is stored. If OK, it is supplied to the non-defective product processing unit 24, and if it is NG, it passes through the defective product processing output unit 25. The defective product processing unit 26 removes the product.

The above-mentioned processing means 10, 11, 14, 1
The reference value and the judgment value setting in 7, 20, 23, 24, 25, 26 and the memory can be configured by hardware or software of an ordinary microcomputer (hereinafter referred to as CPU).

The operation of the non-contact detection device based on the above-mentioned thermography will be described with reference to FIGS. 1 and 3 to 6.

FIG. 3 is a flow chart for explaining the operation of FIG. 2, in which the position sensor 9 detects the position of the cap 3 of the bottle 1 brought to a predetermined position on the belt conveyor 5. The CPU 28 determines the presence or absence of the timing pulse Ts which is the measurement start signal as in the first step S ₁ so that the infrared camera 7 scans the cap 3 surface line-sequentially or by a two-dimensional infrared element using a porometer or the like. By thermal scanning, the thermal image temperature data Td is transferred to the thermal image means 1.
Output to 0.

In the thermal image acquisition means 10, for example, FIG.
The thermal image temperature data Td having an annular shape as shown in FIG. 3 is displayed or stored as a histogram in a display device or a memory (not shown), so that the thermal image Td is obtained as in the second step S ₂ .

After the thermal image temperature data Td is acquired by the thermal image acquisition processing means 10, the environmental temperature fluctuation correction processing means 11 performs the environmental temperature fluctuation correction processing in the third step S ₃ . This environmental temperature variation correction processing will be described with reference to FIG.

The environmental temperature data Tb in the vicinity of the bottle 1 measured by the temperature sensor 8 after obtaining the image temperature data Td in the second step S ₂ in FIG. 1 is shown in FIG. 4 (B) and the first step S.
Get as T ₁ .

Next, the product material of the basis of the maximum temperature data T _{MA X} from the thermal image data Td obtained in the second step S _2, the reference environmental temperature multiplied by a predetermined constant K determined by the shape T _MAX × K = Ta is calculated and a difference Tc from the environmental temperature data Tb (Ta> Tb) obtained from the temperature sensor 8 = Tc =
(Ta-Tb) is obtained as in the second step ST ₂ .
That is, if there is a temperature difference of ΔT between the reference environment temperature Ta and the environment temperature data Tb as shown in FIG. 4B, the reference environment temperature ΔTa and the ring width a are corrected to the ambient environment temperature ΔTb and the ring width b. To be done. Here, A = K × Tc + 1, and K and l are constants.

In the third step ST ₃ , the thermal image data Td 'in which the new environmental change is corrected is obtained as Td' = A × Td, and new thermal image data Td 'is obtained as in the fourth step ST ₄ .

In this way, based on the new thermal image data Td ', as shown in FIG. 3, the quality judgment processing operation of the adhesion state of the aluminum seal 2 of the product is performed.

That is, in the fourth step S ₄ , the CPU 28 (overheat determination processing means 14) determines whether or not it is in the overheat state. This overheating is determined by the synthetic resin molding member used for the aluminum seal 3, for example, about 120 ° C
If the value obtained by adding the judgment value 13 of 140 ° C. and the reference value 12 (threshold value) is YES which is equal to or higher than the measured temperature data, it is judged as NG and the defective product processing is performed by the ninth step S _{9 because the} adhesive strength is too strong. If the fourth step S ₄ is NO, the process proceeds to the next fifth step S ₅ .

In the fifth step S ₅ , the shape defect judgment is CP.
U28 (shape defect processing means 17) is performed. In this shape defect determination, as shown in FIGS. 5A to 5C, A of the infrared thermal image pattern 4 based on the new thermal image data Td '.
5 (B) and 5 (C), the reference values 15 with respect to the temperature in the A-axis (X axis, horizontal axis) and BB 'axis (Y axis, vertical axis) directions are shown.
As shown in the above, the determination values 16 are Δl and Δl, respectively.
If a ″, Δlb ″ and the measured values are la ′ and lb ′, respectively, the defective product is determined based on the following judgment formula (1) of the CPU 28. Compared to the judgment values Δla ″ and Δlb ″, the above condition is | la-
la "| and | lb-lb" | is made as YES larger, defective processing is performed in the ninth step S _9. NO
If so, the CPU 28 (defective defect determination processing means 20) determines whether or not there is a defective defect in the next sixth step S ₆ .

In the sixth step S ₆ , as shown in FIG. 6, the infrared thermal image pattern 4 having an annular shape is taken along the AA ′ axis (X axis).
From the reference temperature Ta on the center line 4a of the upper minus the measured temperature Tb | Ta-Tb |> defective processing proceeds to a ninth step S ₉ when there is a defective defective if the relationship between the judgment value 19 is performed If NO, the process proceeds to the seventh step S ₇ .

In the seventh step S ₇ , the CPU 28 (heating defect determination processing means 23) determines whether or not the heating is defective. When the best temperature value T _MAX of the seventh step S thermal image data newly acquired in ₇ temperature obtained by subtracting the measured value 22 from a reference value 21 product (good) is greater than the determination value 22, namely the judgment formula ( When the condition 2) is satisfied, it is determined that the product is defective and the process proceeds to the ninth step S ₉ . | Reference value - measured value |> determination value ..... (2) Also, the indication that when the heating failure (adhesive strength is weak) and is not judged are good product proceeds to the eighth step S ₈ In addition to being applied to the display device, non-defective processing is performed.

After completion of the eighth and ninth steps S ₈ and S _{9, the process} returns to the first step S ₁ and the next bottle 1 is inspected.

[0039]

According to the non-contact inspection apparatus and the non-contact inspection method by thermography of the present invention, the quality of the joining when the contents are filled in the bottle and the aluminum seal is joined to the opening is displayed on the screen of the CPU or the like. 100% inspection can be performed quickly through the infrared thermal image pattern displayed on the screen, and the thermal image temperature data can be corrected according to the environmental temperature variation, so that the temperature value variation due to the influence of ambient temperature The increase in the defect rate is reduced, and the defect detection accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a flowchart showing an environmental temperature change correction process of a non-contact inspection method using thermography according to the present invention.

FIG. 2 is a system diagram of a non-contact inspection apparatus using thermography according to the present invention.

FIG. 3 is a flowchart showing a product quality determination process of the non-contact inspection method by thermography of the present invention.

FIG. 4 is an explanatory diagram for determining an environmental temperature fluctuation correction method of the non-contact detection method by thermography of the present invention.

FIG. 5 is an explanatory diagram for a shape defect determination method of the non-contact detection method by thermography of the present invention.

FIG. 6 is an explanatory diagram for defect defect determination of the non-contact detection method by thermography of the present invention.

FIG. 7 is an explanatory view of an infrared thermal image pattern on a conventional aluminum seal and a cap fused on an opening of a bottle.

FIG. 8 is a pattern and temperature curve diagram for explaining the influence of a conventional infrared thermal image pattern due to ambient temperature fluctuations.

[Explanation of symbols]

1 ... Bottle, 2 ... Aluminum seal, 7 ... Infrared camera, 8 ... Temperature sensor, 9 ... Position sensor, 10 ... Thermal image acquisition means, 11 ... Environmental temperature fluctuation correction means, 14 ...
... overheating judgment processing means, 17 ... shape defect judgment processing means, 20 ... defect defect judgment processing means, 23 ... heating failure judgment processing means

Continued front page    F term (reference) 2G040 AA07 AB08 BA28 CA17 CA23                       DA06 HA02                 2G051 AA26 AB13 BA06 CA04 CB10                       DA13 EA11 EA12 EA30 EB01                       EB02                 2G066 AC16 BA09 BA60 BC15 CA02                       CA15 CA20

Claims (2)

[Claims] 1. A non-contact inspection device using thermography, which is configured to fuse an annular opening of a resin container with a heat seal and inspect the adhesion of the heat seal through an outer lid. A thermal image acquisition means for acquiring an annular thermal image on the heat seal via an infrared camera arranged on the outer lid of the resin container, and a temperature sensor arranged in a measurement environment of the resin container. And an environmental temperature variation correction processing means for performing temperature variation correction processing with respect to the reference environmental temperature via the above-mentioned heating based on the thermal image pattern data after the environmental temperature variation correction processing by the environmental temperature variation correction processing means. A non-contact inspection device using thermography, which determines whether or not a seal is adhered. 2. A non-contact inspection by thermography, which is designed to seal an annular opening of a resin container by high-frequency heating, fix the opening with an outer lid, and inspect the adhesion of the seal. In the method, a thermal image acquisition step of acquiring an annular thermal image on the seal through an infrared camera arranged on the outer lid of the resin container, and a thermal image acquisition step for arranging in a measurement environment of the resin container. An environmental temperature variation correction processing step for performing a temperature variation correction processing with respect to the reference environmental temperature via an installed temperature sensor, and whether or not the seal is adhered based on the thermal image pattern data after the environmental temperature variation correction processing step. A non-contact inspection method by thermography, which is characterized by making a judgment.