JPS6111643A - Method and device for see through inspection of product defective condition - Google Patents

Abstract

PURPOSE:To detect a defective condition of the material to be inspected by transmitting the light emitted from a light source with its diffusion to a polarizing plate and by placing the substance to be inspected between the polarizing plate thereof and other polarizing plate with light shielding condition at intervals. CONSTITUTION:When a lamp 2 is turned on by a switch 1a, a light is diffused passing through a diffusing plate 3b and the inside polarizing plate body 3 is colored in uniform milky color. Due to the light transmitting the polarizing plate body 3 being shielded by a polarizing film 4a, the inside cannot be seen through from the above of the light shielding plate body 4 and the upper face of the light shielding body 4 looks like the condition of a black colored surface. Now, when a product, for instance a packing material 6 with hot sealing is inserted between the light shielding plate body 4 and the inside polarizing plate body 3, only the packing material 6 can be seen through clearly from the light shielding plate body 4 and the sealing condition thereof can be inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluoroscopic inspection method for inspecting a defective state of a product and an apparatus used therefor.

(Prior art) Conventionally, for example, when it comes to food packaging materials, if they are not completely heat-sealed, those parts tend to tear, resulting in moisture leakage.
This caused unhygienic conditions due to leakage of the filled gas, and in the case of moisture leakage, it also had an adverse effect on other products stacked during transportation. Defects in the heat seal are caused by insufficient heating, insufficient pressure, etc., and conventionally, the defective state of the seal portion has been determined by directly exposing it to light with the naked eye. However, since packaging materials are mainly transparent, it is not possible to determine whether the sealed portion is defective even if they are exposed to light.In reality, sealed packaging materials are randomly selected and subjected to destructive tests by hand. .

Furthermore, if the packaging material is a composite film, it is difficult to inspect the sealed portion and it is difficult to accurately determine the defective state.

Furthermore, it was tiring for the eyes to make judgments by shining light through transparent packaging materials.

(Objective of the present invention) Therefore, the present invention provides a method and apparatus which can eliminate the above-mentioned drawbacks and which can easily and without straining the eyes determine the defective state of a product. Defective product conditions include defects in the heat-sealed part of the food packaging material and defects due to pinholes, as well as defects in the sealing where desiccant has entered the outer seal of the bag filled with desiccant, or plastic. This refers to defects caused by variations in the strength distribution of the product.

(Example) Hereinafter, details of the present invention will be explained along with a method while explaining an example of an apparatus. This example fluoroscopic inspection device S shown in FIG.
1, a light source box houses a fluorescent lamp 2 (see FIG. 2). 1a turns on lamp 2 with the switch attached to box 1.

Turn it off. Reference numeral 6 denotes an inner polarizing plate, which is disposed at the upper end of the box 1. As shown in FIG. 3, the polarizing plate body 6 is made up of a linearly polarizing film 3a held between a milky-white translucent acrylic resin light diffusing plate 6b and an acrylic resin transparent plate 6c, with the light diffusing plate 6b positioned below. I'm letting you do it. In this example, the polarizing film 6a has a thickness of 0.251L, and the light diffusing plate 6b and the transparent plate 3c each have a thickness of 3IIIM. Reference numeral 4 denotes a light-shielding plate body, which is connected to the inner polarizing plate body 6 with a support pin 5 at a predetermined product insertion interval. As shown in FIG. 4, the light shielding plate body 4 includes upper and lower transparent plates 4b made of acrylic resin.

A linearly polarizing film 4a is held between 4c and the light shielding plate 4 is arranged in such a manner that it can block the light transmitted through the inner polarizing plate 6. That is, the lower polarizing film 6a and the upper polarizing film 4a are disposed opposite to each other with their polarization planes being shifted by 90 degrees in a planar state.

Since the apparatus S of this example is configured in this way, when the lamp 2 is turned on by the switch 1a, the light is diffused through the diffusion plate 6b, so that the inner polarizing plate body 6 is colored uniformly milky white. Since the light transmitted through the polarizing plate body 6 is blocked by the polarizing film 4a, the inside cannot be seen through from above the light shielding plate body 4, and the top surface of the light shielding plate body 4 appears as if it were a black surface. In this state, the light shielding plate body 4
When a product, in this example a heat-sealed packaging material 6, is inserted between the light-shielding plate 4 and the inner polarizing plate 6, only the packaging material 6 can be clearly seen through the light-shielding plate 4 as shown in FIG. This is because the refracted light from the inserted packaging material 5 passes through the polarizing film 4a, so only the packaging material 5 can be seen through. In this case, if the heat-sealed portion 6a of the packaging material 6 is in a good sealing state, it can be seen through in the same color and the seal line 6b will also clearly appear. On the other hand, if there is a defective seal part 6C in the heat seal part 6a, the color is different from that of a good seal part and can be seen from above the light shielding plate 4. This is due to the air inside the defective seal.
Differences in color appear due to uneven heat, etc. In this way, according to the method of this embodiment, the defective state of the product can be determined at a glance simply by determining the difference in color from the light shielding plate 4.

(Configuration of the present invention) Although the embodiment is configured as described above, the present invention is not limited to this. For example, in the method of the present invention, any method may be used to diffuse the light from the light source and transmit it through the polarizing plate, and any means for supporting the opposing polarizing plate may be used. On the other hand, in the device invention, regardless of the shape of the inner polarizing plate and the light-shielding plate, the product insertion interval between them is arbitrary, and if they are arranged as shown in Figure 6, defective conditions can be inspected at the assembly line stage. .

The thickness of the polarizing plate used is also not limited;
It may be in the form of a sheet or a plate. Further, the transparent plate supporting the polarizing plate is not limited to a colorless transparent plate, but may be a lightly colored transparent plate. Note that the product to be inspected in the present invention does not matter, and may be a desiccant that is placed in a food packaging bag, and if the desiccant enters the outer seal of the desiccant bag and exhibits a different color part 7 as shown in Fig. 7. It can be determined that the sealing condition is poor. In addition, the strength distribution of plastic products can also be seen through the different colors.

In short, the method invention of the first invention diffuses light from a light source and transmits it through a polarizing plate, and by arranging a product between the polarizing plate and another polarizing plate placed in a light-shielding state at a distance. This is a see-through inspection device for defective product conditions, which is characterized by seeing through the defective state of a heat-sealed portion of the product from the outside of another polarizing plate.

Further, a second device invention includes a light source body and an inner polarizing plate body comprising a colored semi-transparent light diffusing plate and a polarizing plate.

It consists of a polarizing plate supported by a transparent plate and a light shielding plate body, and the light source body, inner polarizing plate body, and light shielding plate body are arranged in this order, and the product insertion interval between the light shielding plate body and the inner polarizing plate body is set. This is a fluoroscopic inspection device for defective products, characterized in that it is placed in a light-shielded state.

(Operations and Effects of the Present Invention) Therefore, according to the method invention, the normal and abnormal parts of the product can be seen in different black colors by simply passing the product between the polarizing plates arranged oppositely in a light-shielding state, and the defective state of the product can be easily detected. The second polarizing plate allows only the product to be seen through, and the outer periphery of the product appears black, so your eyes won't get tired even during long inspection work. Since the light is transmitted through the plate, any part can be seen uniformly. In addition, according to the device invention, in addition to the effects of the method invention,
The advantage is that it has a simple configuration and can be manufactured at low cost.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing one embodiment of the device of the present invention, Fig. 2 is a longitudinal cross-sectional view thereof, Fig. 6 is an enlarged longitudinal cross-sectional view of the main part of the inner polarizing plate, and Fig. 4 is a cross-sectional view of the light shielding plate. Fig. 5 is an enlarged vertical sectional view of the main parts, Fig. 5 is a perspective view of the main parts from the light shielding plate in the product inspection state, Fig. 6 is a longitudinal sectional view of a separate device, and Fig. 7 is a perspective view of other products. be. 2: Fluorescent lamp, 6: Inner polarizing plate, 6b = light diffusing plate, 4: Light shielding plate, 4a, 4b: Transparent plate,
3a, 4a: polarizing film, 6: packaging material,
6a: Heat sealed part, 6c: Defective cool part, 7: Other color part.

Claims (3)

[Claims] (1) Light from a light source is diffused and transmitted through a polarizing plate, and the product is placed between the polarizing plate and another polarizing plate placed in a light-shielding state at a distance. A method for transparently inspecting a defective state of a product, characterized by observing the defective state of a heat-sealed portion of the product from the outside. (2) Consisting of a light source body, an inner polarizing plate body comprising a colored semi-transparent light diffusing plate and a polarizing plate, and a light blocking plate body supporting the polarizing plate with a transparent plate; the light source body, the inner polarizing plate body, and the light blocking plate body. A fluoroscopic inspection device for defective products, characterized in that the light-shielding plate is arranged in the same order as the plate, and the light-shielding plate is placed in a light-shielding state with a product insertion interval from the inner polarizing plate. (3) Claim 2, wherein the polarizing plate is an inner polarizing plate body sandwiched between a colored semi-transparent light diffusing plate and a transparent plate, and the polarizing plate is a light shielding plate body sandwiching the polarizing plate between transparent plates. Fluoroscopic inspection device as described.