JPH07190860A - Measuring method of surface temperature of object to be inspected - Google Patents

Abstract

PURPOSE:To measure the precise distribution of the surface temperature of an object to be inspected by a method wherein a semitransparent or opaque thin-layer sheet is brought into close contact with the surface of the object to be inspected. CONSTITUTION:An air-contained sealed and packaged body A is conveyed by a first conveyor 101. When the air-contained sealed and packaged body A reaches the position of a cold-wind supply device 103, the air-contained sealed and packaged body A is cooled and treated by the colod-wind supply device 103. Thereby, the temperature difference between a part coming into contact with a gas on the surface of the air- contained sealed and packaged body and a part coming into contact with a filled object in the air-contained sealed and packaged body can be clear. Then, a detector 211 detects a temperature on the surface of the air-contained sealed and packaged body A on the basis of infrared rays radiated from the air-contained sealed and packaged body A on the first conveyor 101. In succession, the area of the part coming into contact with the gas on the surface of the air-contained sealed and packaged body is detected, and a good product is discriminated from a defective product by judging whether the area is within a prescribed range or not.

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 surface temperature distribution of an object to be inspected by radiating electromagnetic waves, and more specifically for inspecting the state of an object to be inspected, for example, a substance in a hermetically sealed package. The present invention relates to a method for measuring the surface temperature distribution of an object to be inspected with a radiated electromagnetic wave.

[0002]

BACKGROUND OF THE INVENTION An airtight sealed package in which a liquid food such as curry or stew and a gas such as air or an inert gas are housed and sealed in a retort pouch is a rotary type which is pressurized and heated while being rotated. Retort sterilization is being performed. The present inventors have found from the results of many experiments that in this rotary retort sterilization treatment, the ratio of the gas contained, that is, the air content, has a great influence on the efficiency of the sterilization treatment, that is, the sterilization effect. did. That is, if the air content of the airtight sealed package is 2 to 50%, the sterilization effect becomes large, and if the variation of the air content between a plurality of airtight sealed packages is -3 to 10%, the sterilization failure will occur. It was concluded that the homogeneity and the deterioration of the contents due to overheating are reduced. By the way, since the retort pouch container formed by the flexible film is flexible, it is very difficult to adjust or measure the air content as compared with a rigid or semi-rigid cup, tray, or the like. . Based on the present situation, the present inventors have made a method and an apparatus capable of continuously measuring the air content of an airtight hermetically sealed package in a non-contact manner rapidly and highly accurately, particularly for industrial use. To calculate the air content by detecting the temperature distribution on the surface of the airtight sealed package, and a method for measuring the air content of the airtight sealed package, and an airtight sealed package. An air content measuring device for an airtight sealed package, comprising: a mounting table to be placed, and a detection unit which is arranged in the vicinity of the mounting table and detects a temperature distribution on the surface of the airtight sealed package. Filed earlier.

The inventors of the present invention conducted a confirmation experiment with various sealed packages to measure the temperature distribution on the surface of the above-mentioned sealed packages, and found that characters, patterns and the like were printed on the surface of the sealed packages. If applied, there is a difference in the radiated electromagnetic waves on the surface of the hermetically sealed package between the printed part and the non-printed part, and therefore it may not be possible to measure the accurate temperature distribution on the surface of the hermetically sealed package. I encountered the phenomenon. The present inventors, as a result of earnest research focusing on such a phenomenon,
It was found that the problem can be effectively solved by bringing a semitransparent or opaque thin layer sheet into close contact with the surface of the hermetically sealed package. Further, such means can be applied not only to the case of the hermetically sealed package but also to the case of other containers, and further to the fields other than foods, such as the fields of medicines and paints, as long as they emit radiated electromagnetic waves. I got the knowledge that I can.

[0004]

SUMMARY OF THE INVENTION The present invention is not limited to a hermetically sealed package having characters or patterns printed on the surface thereof, but can be used to measure an accurate temperature distribution on the surface of an object to be inspected which emits radiated electromagnetic waves. The object is to provide a method for measuring the surface temperature of an inspection object.

[0005]

The present invention is a method for detecting an index relating to a projected image of an object to be inspected by measuring a surface temperature distribution of the object to be inspected by a radiated electromagnetic wave, which is semitransparent or opaque on the surface of the object to be inspected. A method for measuring the surface temperature of an object to be inspected, characterized in that a thin layer sheet is brought into close contact so that the emissivity of the surface of the object to be inspected falls within a predetermined range. As a method for closely adhering the thin layer sheet to the surface of the inspection object,
A method of adhering the thin layer sheet to the surface of the object to be inspected as it is, a method of pressing the surface of the object to be inspected by attaching the thin layer sheet to the hole portion of the pressing plate having a hole in the center,
When the inspection object is a hermetically sealed package wrapped with a flexible package, the latter method is preferably adopted. The thin layer sheet that can be used in the present invention is not particularly limited as long as it is a translucent or opaque thin layer sheet,
Examples include silicon rubber, synthetic resin such as polyethylene, and metal foil such as aluminum foil, and the sheet thickness is 0.0
It is preferably about 1 to 0.2 mm. Further, when the thin layer sheet is attached to the hole portion of the pressing plate having a hole in the center, it is preferable to use synthetic resin such as silicone rubber or polyethylene which has elasticity to some extent.

[0006]

According to the above construction, by adhering the semitransparent or opaque thin layer sheet to the surface of the inspection object, it is possible to determine whether or not characters or patterns are printed on the surface of the inspection object. Nevertheless, it is possible to accurately measure the distribution of the surface temperature of the inspection object. Therefore, for example, in a sealed package containing a fluid such as liquid and the like, gas, water and oil having different specific gravities, and separating by standing,
This is effective when the content of a fluid having a low specific gravity is to be verified by measuring the surface temperature distribution of the sealed package with radiated electromagnetic waves.

[0007]

EXAMPLE An apparatus for measuring an airtight sealed package according to an example of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a defective product detection device 1 for an airtight sealed package is obtained by filling and sealing a filling such as curry or stew with a gas such as air or an inert gas in a retort pouch. First conveyor (conveying path) 10 for conveying the hermetically sealed package in a lying state
Has 1. In addition, it is possible to keep the position of the gas in each air-tight sealed package without variation and to make the volume of the gas in the air-tight sealed package more highly accurate so that the standing pouch etc. always keep a constant shape. It is desirable because it enables stable and stable measurement. As such means, in the present invention, in detecting the surface temperature of the airtight sealed package A by a detector 211 of the first conveyor 101 described later, the airtight sealed package A is pressed by a pressing plate having a hole in the center. . Thereby, as described above, the shape of the gas in the airtight sealed package can be kept constant. In this case, it is preferable that the pressing plate has a shape similar to the shape of the hermetically sealed package and the shape of the central hole is circular or elliptical.
As shown in FIG. 3, when the maximum diameter of the hole of the pressing plate is a and the maximum diameter in the direction orthogonal to this is b, the size of the hole is b: a = 1: 1 to 2, When the maximum diameter of the upper surface of the hole of the plate is c and the maximum diameter of the lower surface of the hole of the pressing plate is d, it is preferable that c: d = 1: 1 to 3 is satisfied. Further, as the pressing plate, t = 0. Where the thickness of the hermetically sealed package is T and the thickness of the pressing plate is t.
It is preferable to set it to 05 to 1T.

Then, a semitransparent or opaque thin layer sheet is attached to the central hole of the pressing plate. As a result, even if characters or patterns are printed on the surface of the hermetically sealed package, the emissivity of infrared rays on the surface of the hermetically sealed package can be made uniform. At the downstream end of the first conveyor 101, a second conveyor 201 for conveying a good product of the airtight sealed package to the next step such as a sterilization step,
A third conveyor 301 for conveying defective products of the airtight sealed package is connected, and further, the first conveyor 101, the second conveyor 201, and the third conveyor 301.
A swinging member 2 for selecting an airtight sealed package body depending on whether or not it has a predetermined air content is disposed in the vicinity of the connecting portion with. By switching the swinging member 2, the first conveyor 101 is moved to the second conveyor 201.
Alternatively, it is selectively communicated with the second conveyor 301, and whether the air-tight sealed package has a predetermined air content, that is, a good product and a defective product are sorted. A cold air supply device 103 for cooling the air-containing hermetically sealed package is provided in the middle of the convey path of the conveyor 101. As a result, a portion of the surface of the airtight hermetically sealed package which is in contact with the gas in the airtight hermetically sealed package (hereinafter referred to as a portion of the surface of the airtight hermetically sealed package which is in contact with the gas) and the airtightly sealed package surface By utilizing the difference in heat capacity between the contents in the package, that is, the part in contact with the filling (hereinafter referred to as the part in contact with the filling on the surface of the airtight sealed package), both temperatures can be clearly distinguished. To adopt the above cooling means, curry immediately after the filling is cooked,
It is particularly effective when the temperature is high such as stew. As the cooling means, instead of the cold air supply device, a cold water supply device that pours cold water into the air-containing sealed package in a shower or spray form, or a cold water tank in which the air-sealed package is immersed in cold water. It can also be adopted.

Further, instead of the cooling means, a heating means can be adopted. The adoption of heating means is particularly effective when the filling material has a low temperature. As the heating means, a hot air supply device for blowing hot air to the air-tight sealed package,
There are a hot water supply device for pouring hot water into the air-sealed sealed package in a shower or spray form, or a hot water tank for immersing the air-sealed sealed package in hot water. In the vicinity of the cold air supply device 103 in the middle of the transport path of the first conveyor 101, upward,
A detector 211 is arranged to detect the temperature of the surface of the airtight sealed package A by infrared rays emitted from the airtight sealed package A on the first conveyor 101. The detector 211 is
A circuit 20 for converting the obtained temperature information into thermal image data, a storage unit 30 for storing the thermal image data, a detection unit 40 for detecting the area of a portion in a predetermined temperature range based on the thermal image data, and a detection unit 40. The determination circuit 50 for determining whether or not the obtained area is within a predetermined range, and the control unit 60 for controlling the sorting means (the swinging member 2) based on the determination result obtained by the determination circuit 50 are sequentially connected. ing. Detector 211
May detect a temperature distribution image of the entire surface of the airtight sealed package A, or detect the temperature of one or more points on the surface of the airtight sealed package A. May be.

Next, a defective product detection device 1 for an airtight sealed package.
The action of will be described. The defective product detection apparatus 1 for an airtight hermetically sealed package having the above-described configuration first includes the first conveyor 101.
Thus, the airtight sealed package A is continuously conveyed. When the air-containing sealed package A reaches the position of the cold air supply device 103, the air-containing sealed package A is cooled by the cold air supply device 103. As a result, as shown in FIG. 2, it is possible to clarify the temperature difference between the portion B of the surface of the airtight sealed package which is in contact with the gas l and the portion C of the surface of the airtight sealed package which is in contact with the filling m. An example of the cold air condition is −30 to 30 ° C. Simultaneously with or immediately after the cooling process, the detector 2
Reference numeral 11 detects the temperature of the surface of the airtight sealed package A by infrared rays emitted from the airtight sealed package A on the first conveyor 101. The obtained temperature information is converted into thermal image data by the circuit 20 for converting into thermal image data, and stored in the storage unit 30. Then, the detection unit 40 detects the area of the portion of the surface of the airtight sealed package in the predetermined temperature range, that is, the area of the portion B in contact with the gas on the surface of the airtight sealed package, based on the thermal image data ( The above-mentioned predetermined temperature range is, for example, 30 to 30 when the temperature of the filling is 70 ° C.
50 ° C). Next, the determination circuit 50 determines whether or not the area is within a predetermined range.

In the airtight sealed package, the area of the surface of the airtight sealed package which is in contact with gas is correlated with the volume of the gas in the airtight sealed package, that is, the air content. Therefore, by determining whether the area of the surface of the airtight hermetically sealed package in contact with the gas is within a predetermined range, whether or not the volume of the gas in the airtight hermetically sealed package is within an appropriate range. Can be easily determined. In addition, the specific correlation between the area of the gas-containing hermetically sealed package surface in contact with the gas and the volume of the gas in the gas-containing hermetically sealed package is as follows. This can be easily known by changing only the volume of gas variously and examining how the area of the surface of the airtight sealed package which is in contact with gas changes. In the above judgment, when the area is within the predetermined range, it is judged that the airtight hermetically sealed package A is a non-defective product in which the air content of the gas is within the predetermined range, while the area is not within the predetermined range. In this case, the airtight sealed package is judged to be a defective product having too much or too little air content. Based on the determination result of the determination circuit 50, the control circuit 60
Controls the swinging member 2 between the time when the temperature of the surface of the airtight sealed package A is detected by the detector 211 and the time when the airtight sealed package A reaches the end of the first conveyor 101. . The oscillating member 2 selectively communicates the first conveyor 101 with the second conveyor 201 or the third conveyor 301 based on the control signal. As a result, non-defective products of the airtight sealed package A are sent to the second conveyor 201, and defective products of the airtight sealed package A are sent to the third conveyor 301.

In another embodiment of the present invention, the detector may be arranged downstream of the cold air supply device. Further, as another embodiment of the present invention, in place of the determination circuit for determining whether the area obtained by the detecting means is within a predetermined range, the area obtained by the detecting means And a determination circuit for determining whether the volume of the gas in the airtight sealed package obtained by the calculation circuit is within a predetermined range. As still another embodiment of the present invention, when there is a large temperature difference between the filling and room temperature, the cooling means and heating means described above are not provided. Even in this case, if a certain period of time elapses after filling the contents, the temperature difference between the portion of the surface of the airtight sealed package that comes into contact with the gas and the portion that comes into contact with the contents, i.e., the filling, appears, and the gas is detected by the detector It becomes possible to measure the rate.

[0013]

According to the present invention, it is possible to determine whether characters or patterns are printed on the surface of the object to be inspected by simply adhering the semitransparent or opaque thin layer sheet to the surface of the object to be inspected. Regardless of this, it is possible to accurately measure the distribution of the surface temperature of the inspection object. Therefore, for example, in a sealed package containing a fluid such as liquid and the like, gas, water and oil, which have different specific gravities and which are separated by standing,
This is effective when the content of a fluid having a low specific gravity is to be verified by measuring the surface temperature distribution of the sealed package with radiated electromagnetic waves. Further, in the measurement, by pressing the hermetically sealed package with a holding plate having a hole in the center, the above-mentioned measurement can be performed more accurately.

[Brief description of drawings]

FIG. 1 is a structural explanatory view of a measuring device for an airtight sealed package according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of an airtight sealed package.

FIG. 3 is a plan view of a pressing plate.

[Explanation of symbols]

 A Airtight sealed package 1 Defective product detection device for airtight sealed package 2 Swing member 20 Circuit for converting temperature information into thermal image data 30 Storage unit for storing thermal image data 40 Detecting means 50 Judgment circuit 60 Control circuit 101 First Conveyor 103 Cold Air Supply Device 201 Second Conveyor 211 Detector 301 Third Conveyor

Claims (4)

[Claims] 1. A method for detecting an index relating to a projected image of an object to be inspected by measuring a surface temperature distribution of the object to be inspected with a radiated electromagnetic wave, comprising a semi-transparent or opaque thin sheet on the surface of the object to be inspected. A method for measuring the surface temperature of an object to be inspected, which is characterized in that the emissivity of the surface of the object to be inspected is within a predetermined range. 2. The method for measuring the surface temperature of an object to be inspected according to claim 1, wherein the object to be inspected is a hermetically sealed package wrapped with a flexible package. 3. The method for measuring the surface temperature of an object to be inspected according to claim 1, wherein the surface of the hermetically sealed package is pressed by a pressing plate having a hole in the center. 4. The method for measuring the surface temperature of an object to be inspected according to claim 1, wherein a semi-transparent or opaque thin layer sheet is put on the hole portion of the pressing plate having a hole in the center.