JPH11287729A - Method and apparatus for detecting liquid leak - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect a liquid leak of any kind from any liquid container by irradiating an infrared light to an object to be inspected and picking up an image of the object by an infrared camera which has a spectral filter passing only a specific absorption wavelength region of water. SOLUTION: When an infrared light is irradiated from an infrared light source 3 to an object 1 to be inspected which is filled with a liquid, a water drop (moisture) 2 absorbs only a specific wavelength of the infrared light. An image of the infrared light is picked up by an infrared camera 5 having a spectral filter 4 which passes only the specific wavelength, whereby only a shadow image because of the water drop 2 is formed and the other pattern printed on a liquid container, a sealing seal, etc., are not picked up. In other words, when the object 1 to be inspected does not leak, no shadow is formed at all. When the object 1 leaks, the shadow image of the water drop 2 is picked up. The image data obtained by the infrared camera 5 are inputted to a computer 6 having a judging means, whereby the leak is judged to be present from the shadow image 7 by the water drop or the leak is judged to be absent from the absence of the shadow image accurately and efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid container filled with water-based contents (liquor, juice, soft drinks, etc.), for determining whether there is any liquid leakage due to insufficient sealing or breakage. The present invention relates to a technology for detecting whether

[0002]

2. Description of the Related Art Conventionally, as a method of detecting such a liquid leak, an image is taken with a camera having sensitivity in a visible light region,
A method has been adopted in which water droplets (moisture) and other objects (for example, a picture of a liquid container) are binarized to distinguish and identify them. In the above method, (1) it is difficult to determine water droplets (moisture) depending on the pattern of the liquid container. (2) Water droplets (moisture) adhering to a highly reflective substrate such as aluminum cannot be determined. (3) The binarization level must be adjusted depending on the liquid type of the contents. For example, a dark liquid such as coffee and a transparent liquid such as cider have different binarization thresholds (threshold levels). (4) If the binarization level is strict, foreign substances such as paper dust are detected, and even those without liquid leakage are splashed, resulting in inconvenience such as increased waste.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned inconveniences, and is capable of accurately detecting liquid leakage regardless of the type of liquid or the type of liquid container. It is an object of the present invention to detect and reduce waste, and to reduce the detection cost.

[0004]

According to the present invention, there is provided an infrared camera having a spectral filter which irradiates an inspection object with infrared light from an infrared light source and transmits only a specific absorption wavelength region of water. A liquid leakage detection method is characterized in that an object to be inspected is photographed, and a determination is made based on the presence or absence of a seal image of a water droplet.

According to a second aspect of the present invention, there is provided the liquid leakage detecting method according to the first aspect, wherein the specific absorption wavelength range of the water is 2.5 to 3.2 μm.

According to a third aspect of the present invention, there is provided a spectrometer for irradiating an inspection object on a line for transporting the inspection object with infrared light from an infrared light source and transmitting only a specific absorption wavelength region of water. An infrared camera having a filter is used to photograph an object to be inspected, and a removing means is provided for removing the inspected object from the line when an imprint image of a water droplet is inputted to a computer having a judging means. This is a liquid leak detection device.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIG. When the inspection object (1) filled with liquid is irradiated with infrared light from the infrared light source (3), the water droplet (moisture) absorbs only a specific wavelength of the infrared light. When this is photographed by an infrared camera (5) provided with a spectral filter (4) that transmits only a specific wavelength, only the imprint image by the water droplet (moisture) (2) appears, and a picture printed on another liquid container is taken. , Sealing seals and the like will not be reflected. That is, when there is no leakage in the inspection object, no seal image is displayed, and when there is leakage, a seal image of a water drop (moisture) is displayed.

[0008] Image data taken by the infrared camera (5) is input to a computer having a judging means, and if there is an imprint image due to water droplets (moisture), leakage has occurred.
When there is no leak, it can be detected accurately and efficiently as if there is no leak.

As shown in FIG. 2, the infrared absorption wavelength of water is 2.5 to 3.2 μm, and the peak absorption wavelength is 2.95 μm.
It has become. Therefore, the specific absorption wavelength region is set to 2.5 to 3.
By setting the thickness to 2 μm, detection is performed accurately and efficiently.

FIG. 3 shows the most common spout of liquid containers in which the contents (juice) are filled into a paper-based liquid container using the above detection method, and a sealing seal is attached to the upper spout. 1 shows an example of detecting a leak from a device. The inspection object (1A, 1B, 1C, 1D, 1E) irradiates the infrared light source (3) by the transport line (9) and sequentially passes through the position where the infrared camera (5) takes an image. Since the imprinted image of the water drop (water) is projected on the 1C inspection object having liquid leakage, the computer determines that the inspection object is to be removed by the determination means, and a command is transmitted to the removal means to cause the leakage. The inspection object of 1C is removed from the transport line.

As a means for removing the inspection object from the transport line, an ordinary removing means for grasping, pushing away from the side by force, or changing the direction to a line for transporting a defective product is used.

The substrate of the liquid container to be inspected is not particularly limited, and may be metals such as aluminum and steel, plastics such as polyester, polyethylene and polypropylene, paper or a composite material thereof. .

The above example is an embodiment for detecting a leak from the upper drinking spout, but the position of the infrared camera may be appropriately selected depending on the position to be inspected.

[0014]

According to the present invention, since the absorption wavelength of water is used, (1) it is not affected by the design and shape of the liquid container. (2) Leakage can be detected even on a highly reflective substrate such as aluminum. (3) Depending on the liquid type of the contents,
No need to adjust settings. (4) There is no erroneous detection of paper dust etc. other than water droplets. Therefore, it is a leak detection method that is versatile.

Since the determination is made based on whether there is an imprint image of water droplets (moisture), there is no need for special pattern recognition and positioning software, the circuit of the determination means is simple, and a single high-speed transport line can be used. . In addition, equipment and inspection costs are low.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a leak detection method of the present invention.

FIG. 2 is a graph showing an absorption wavelength region of water.

FIG. 3 is a schematic configuration diagram illustrating an embodiment using the leak detection method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Inspection object 2 ... Water drop (moisture) 3 ... Infrared light source 4 ... Interference spectroscopy filter 5 ... Infrared camera 6 ... Computer 7 ... Imprint image of water drop 8 ... Removal means 9 ... Transport line

Continuing from the front page (72) Katsuyuki Kano, Inventor, 1-5-1, Taito, Taito-ku, Tokyo Letterpress Printing Co., Ltd. (72) Hiroto Okada 1-1-1, Taito, Taito-ku, Tokyo Letterpress, Inventor (72) Inventor Keiji Fukumura 2-4-131 Kutaro-cho, Chuo-ku, Osaka-shi, Osaka Prefecture Kurashiki Spinning Co., Ltd. Osaka Head Office (72) Inventor Yoshio Takada 2-4-2 Kutaro-cho, Chuo-ku, Osaka-shi, Osaka No. 31 Kurashiki Spinning Co., Ltd. Osaka Head Office (72) Inventor Kiyoshi Morishige 2-4-1 Kutaro-cho, Chuo-ku, Osaka-shi, Osaka Kurashiki Spinning Co., Ltd. Osaka Head Office

Claims (3)

[Claims] 1. An object to be inspected is irradiated with infrared light from an infrared light source, and the object is photographed by an infrared camera having a spectral filter that transmits only a specific absorption wavelength region of water. A liquid leakage detection method characterized by determining. 2. The specific absorption wavelength range of the water is 2.5-3.
2. The liquid leakage detection method according to claim 1, wherein the thickness is 2 μm. 3. An infrared camera irradiates an infrared light from an infrared light source to an inspection object on a line for transporting the inspection object, and uses an infrared camera having a spectral filter that transmits only a specific absorption wavelength region of water. A liquid leakage detection device comprising: a removing unit that removes an object to be inspected from a line when an image is captured and input to a computer having a determining unit and an imprint image of a water droplet is confirmed.