JP7327144B2 - Inspection device and inspection method for fiber structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fiber structure inspection device and inspection method, and more particularly to a fiber structure inspection device and inspection method for inspecting the quality of a board-like or mat-like fiber structure.

As a conventional fiber structure, a fiber board containing plant fibers such as kenaf and thermoplastic resin fibers is generally known. (See, for example, Patent Document 1). This fiber board is obtained, for example, by thermally compressing a fiber mat containing vegetable fibers and thermoplastic resin fibers. In addition, fiberboards are used, for example, in vehicle door trims, seat backboards, package trays, and the like.

JP 2019-72924 A

In the above-mentioned fiber board, non-uniformity may occur depending on the mixing ratio and degree of mixing of the vegetable fibers and the thermoplastic resin fibers in the fiber mat, and there may be areas with high light transmittance (translucency), resulting in poor quality. Therefore, it is conceivable to inspect the degree of transparency of the fiber board, but the degree of transparency depends on the type of fiber board (for example, the type of fiber board with different uses, thickness, basis weight, etc.). Otherwise, it is not possible to accurately judge whether it is good or bad. However, at present, no technology has been established that can appropriately change the inspection conditions according to the type of fiber board and accurately inspect the degree of transparency of the fiber board. In addition to the fiber board, the above-mentioned problems also occur in fiber structures such as fiber mats.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an inspection apparatus and an inspection method for a board-like or mat-like fiber structure that determines the quality of the board-like or mat-like fiber structure based on the light transmittance. do.

In order to solve the above problem, the invention according to claim 1 is a fiber structure inspection apparatus for inspecting the quality of a board-like or mat-like fiber structure, wherein a light source is provided on the back surface of the fiber structure. A photographing device for photographing the surface of the fiber structure in a state of being irradiated with light, and the area of the part whose brightness is equal to or higher than a predetermined threshold value in the photographed image is obtained as the area of the transmitting part, and the size of the area of the transmitting part or Determination means for determining the quality of the fiber structure based on the ratio of the surface area of the fiber structure to the surface area of the fiber structure; A condition changing means for changing at least one of the amount of light incident on the photographing device, the sensitivity of the photographing device, and the threshold value.
The invention according to claim 2 is based on the invention according to claim 1, wherein the condition changing means changes a light reduction plate for changing the illuminance of the back surface of the fiber structure, or changes the amount of incident light to the photographing device. The gist is to provide a light reducing plate for
The invention according to claim 3 is the invention according to claim 2, wherein an inspection box is provided in which a darkroom is formed, the light source is arranged on one end side thereof, and the imaging device is arranged on the other end side thereof, The inspection box has a doorway for inserting and removing the fiber structure between the light source and the imaging device in the darkroom, and between the light source or the imaging device in the darkroom and the fiber structure. The gist is that a light-reducing plate entrance/exit for inserting and removing the light-reducing plate is formed.
The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the determination means determines that the total area of the transmission parts is a predetermined ratio to the surface area of the fiber structure. The gist is to determine that the product is defective when it meets the above conditions.
The invention according to claim 5 is characterized in that, in the invention according to any one of claims 1 to 4, the fiber structure is a fiber board containing vegetable fibers and a thermoplastic resin.
In order to solve the above problem, the invention according to claim 6 is a fiber structure inspection method for inspecting the quality of a board-like or mat-like fiber structure, wherein a light source is provided on the back surface of the fiber structure. A photographing step of photographing the surface of the fiber structure while being irradiated with light, obtaining an area of a part whose brightness is equal to or higher than a predetermined threshold value in the photographed image as a transmission part area, and determining the size of the transmission part area or a determination step of determining whether the fiber structure is good or bad based on the ratio of the surface area of the fiber structure to the surface area; and a condition changing step of changing at least one of the amount of light incident on the photographing device, the sensitivity of the photographing device, and the threshold value.

According to the fiber structure inspection apparatus of the present invention, there is provided a photographing device for photographing the surface of the fiber structure while the back surface of the fiber structure is irradiated with light from a light source, and the photographed image has a brightness equal to or higher than a predetermined threshold. determining means for determining the quality of the fiber structure based on the size of the area of the transmission portion or the ratio of the area of the transmission portion to the surface area of the fiber structure; , the intensity of the light source, the illuminance of the back surface of the fiber structure, the amount of light incident on the imaging device, the sensitivity of the imaging device, and a threshold. This makes it possible to determine the quality of the board-like or mat-like fiber structure by obtaining the area, distribution, ratio to the whole, etc. of the portion having relatively high light transmittance. Furthermore, the inspection conditions can be appropriately changed according to the type of the fiber structure by the condition changing means. As a result, the quality of the fiber structure can be inspected according to a certain standard.
Further, when the condition changing means includes a light-reducing plate for changing the illuminance of the back surface of the fiber structure or a light-reducing plate for changing the amount of light incident on the photographing device, the light-reducing plate is used to change the fiber structure. It is possible to effectively change the illuminance of the back surface of the body or the amount of incident light to the imaging device.
Further, if an inspection box forming a darkroom is provided, and the inspection box is provided with a doorway for taking in and out the fiber structure and a light-reducing plate doorway for taking in and out a light-reducing plate, the doorway is used for the inspection box. The fiber structure and the attenuating plate can be easily put in and taken out from.
In addition, when the determination means determines that the total area of the transmitting portion is a predetermined ratio or more with respect to the surface area of the fiber structure as being defective, the fiber structure having a locally different degree of transparency may be used. Even if there is, it can be accurately inspected for acceptance or rejection.
Furthermore, when the fiber structure is a fiber board containing reinforcing fibers and a thermoplastic resin, quality can be accurately inspected by the degree of transparency of the fiber board.
According to the method for inspecting a fiber structure of the present invention, the photographing step of photographing the surface of the fiber structure while the back surface of the fiber structure is irradiated with light from a light source, determining the quality of the fiber structure based on the size of the area of the transmission portion or the ratio of the area of the transmission portion to the surface area of the fiber structure; , the intensity of the light source, the illuminance of the back surface of the fiber structure, the amount of light incident on the imaging device, the sensitivity of the imaging device, and a threshold value. This makes it possible to determine the quality of the board-like or mat-like fiber structure by obtaining the area, distribution, ratio to the whole, etc. of the portion having relatively high light transmittance. Furthermore, the condition changing process can appropriately change the inspection conditions according to the type of the fiber structure. As a result, the quality of the fiber structure can be inspected according to a certain standard.

The present invention will be further described in the following detailed description by way of non-limiting examples of exemplary embodiments according to the invention and with reference to the mentioned drawings, wherein like reference numerals indicate Similar parts are shown throughout the several figures.
BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of the inspection apparatus of the fiber board which concerns on an Example, (a) shows the state which does not arrange|position a light reduction plate in an inspection box, (b) shows the state which arrange|positions a light reduction plate in an inspection box. FIG. 5 is a flowchart for explaining control processing of a control unit according to the embodiment; It is an explanatory view for explaining an arrangement form of a fiber board to the above-mentioned inspection box. It is an explanatory diagram for explaining the insertion form of the light reduction plate into the inspection box, (a) shows the arrangement form of one light reduction plate, (b) shows the arrangement form of a plurality of light reduction plates, (c) shows a configuration in which no light-reducing plate is arranged; BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing for demonstrating the inspection method of the fiber board which concerns on an Example, (a) shows the test|inspection form which arrange|positioned the light reduction plate in an inspection box, (b) shows the light reduction plate not arrange|positioned in an inspection box. Shows the type of examination. It is explanatory drawing for demonstrating the test|inspection form which has arrange|positioned the darkening plate in the said inspection box. It is explanatory drawing for demonstrating the inspection form which does not arrange|position a light-attenuating plate in the said inspection box, (a) shows a picked-up image, (b) shows a binarized image.

The material presented herein is intended to be illustrative and illustrative of the embodiments of the invention and is believed to be the most effective and readily understood description of the principles and conceptual features of the invention. It is stated for the purpose of providing what it seems. In this regard, no attempt is made to show structural details of the invention beyond those necessary for a fundamental understanding of the invention, and the description in conjunction with the drawings will illustrate some aspects of the invention. It will be clear to those skilled in the art how it is actually implemented.

<Inspection device for fiber structure>
For example, as shown in FIGS. 1 and 2, the fiber structure inspection device according to the present embodiment is a fiber structure inspection device (1 ), a photographing device (3) for photographing the surface of the fiber structure (FB) while the back surface of the fiber structure (FB) is irradiated with the light of the light source (2), and the photographed images (P1, P2 ), the area of the part whose brightness is equal to or higher than a predetermined threshold value is obtained as the transmission area (S), and based on the size of the transmission area (S) or the ratio (R) to the surface area of the fiber structure (FB) The strength of the light source (2), the illuminance of the back surface of the fiber structure (FB), the imaging device ( 3), a condition changing means for changing at least one of the amount of incident light to the imaging device (3), the sensitivity of the imaging device (3), and the threshold value.

The type, number, and layout of the light sources (2) are not particularly limited. Examples of the light source (2) include light emitting diodes, incandescent lamps (fluorescent lamps), and the like. In addition, a plurality of light sources (2) can be provided according to the size of the fiber structure (FB), for example, so that the entire rear surface of the fiber structure (FB) is uniformly illuminated with light. The light source (2) is configured such that light emitting diodes are linearly arranged in parallel with one side of the fiber structure (FB), and the linear light source is swept in parallel with the surface of the fiber structure (FB). may
There is no particular limitation on the type and layout of the photographing device (3). As the photographing device (3), for example, a digital camera (digital still camera, digital video camera, etc.), which is a general visible light camera, can be used.

The determining means can determine, as a transmissive portion, a region in which the brightness is equal to or higher than a set threshold value in the captured image. For this reason, the determination means can be configured to binarize the photographed image using a threshold value and obtain the area of the transparent portion based on the binarized image.
The determination mode, timing, etc. of the determination means are not particularly limited. For example, as shown in FIG. 2, this determination means can determine that the fiber structure (FB) is defective when the total transmission area (S) is equal to or greater than a predetermined ratio with respect to the surface area of the fiber structure (FB). . In addition, when the transmitting portion area (S) is a certain size or more, or when there are a predetermined number or more of portions having a transmitting portion area (S) of a certain amount or more, it can be determined to be defective. The judging means can notify the judgment result by, for example, a display screen, a display unit such as a light emitting element, a buzzer, or the like.

The condition changing form, timing, etc. of the condition changing means are not particularly limited. This condition changing means can change, for example, the intensity of the light source (2). In this case, for example, the intensity of the light source can be changed by replacing the light source in the inspection box (5) with another light source (for example, a light source with different luminous flux, luminous intensity, etc.). Furthermore, for example, the intensity of the light source can be changed by operating a dimming function, a current adjusting function, a toning function, etc. provided on the light source (2) side.

The condition changing means can change, for example, the illuminance of the back surface of the fiber structure (FB) or the amount of light incident on the photographing device (3). In this case, for example, as shown in FIG. 5, the condition changing means may be a light reducing plate (13) for reducing the illuminance of the back surface of the fiber structure (FB), or dimmer plate (14). Accordingly, by appropriately selecting the presence/absence, density, number, type, etc. of the light reduction plates (13, 14), the desired illuminance on the back surface of the fiber structure (FB) or the amount of incident light to the imaging device (3) can be easily obtained. can get to Examples of the dimming plates (13, 14) include a printed glass plate, a translucent plate, and the like. It may also be configured to change the sensitivity of the photosensor of the imaging device (3).

When the dimming plates (13, 14) are provided, for example, as shown in FIG. 1, a darkroom is formed, with a light source (2) arranged at one end thereof and a photographing device (3) at the other end thereof. An inspection box (5) is arranged, and the inspection box (5) has a doorway (6) for putting the fiber structure (FB) in and out between the light source (2) and the imaging device (3) in the dark room. and a light-reducing plate entrance (7) for inserting and removing the light-reducing plates (13, 14) between the light source (2) or the imaging device (3) in the darkroom and the fiber structure (FB). can be done.

In addition, as another condition changing means, for example, as shown in FIG. A form of changing the illuminance of the back surface of the fiber structure (FB) or the amount of incident light to the photographing device (3) is exemplified.

The condition changing means can change, for example, the sensitivity of the photographing device (3). In this case, for example, the sensitivity can be changed by operating a sensitivity adjustment function provided in the photographing device (3), or by attaching a filter to the lens of the photographing device (3).

The condition changing means can include, for example, threshold changing means for changing the threshold for judging the brightness in the photographed image photographed by the photographing device (3). For example, as shown in FIG. 2, this threshold value changing means changes a plurality of pre-stored values when information indicating the type of fiber structure (FB) to be inspected (for example, vehicle model number) is input. A threshold corresponding to the information can be called out of the thresholds (for example, the binarization threshold, etc.). The judging means can obtain the area of the part that is equal to or larger than the threshold value in the captured image as the transmission area (S).

The condition changing means is, for example, a judgment value changing means for changing the judgment value used as a reference such as the size of the transmitting portion area (S) and the ratio to the total area when judging the quality of the fiber structure (FB). can be provided. For example, as shown in FIG. 2, this determination value changing means changes a plurality of values stored in advance when information indicating the type of fiber structure (FB) to be inspected (for example, a vehicle model number) is input. (for example, see-through area ratio determination value), the determination value corresponding to the information can be called.

As long as the fiber structure (FB) is a board-like or mat-like structure containing fibers (in particular, plant fibers), its material, size, use, etc. are not particularly limited. The inspection of the degree of transparency of the fiber structure (FB) is usually performed according to the type of fiber structure (for example, the use of the fiber structure (for example, the type of vehicle), the type with different thickness, basis weight, etc.) It is necessary to change the inspection conditions.
Examples of the fiber structure include a fiber board (FB) containing vegetable fibers (especially kenaf fibers) and thermoplastic resin, and a fiber mat containing vegetable fibers and thermoplastic resin fibers. This fiber board is usually obtained by heating and compressing a fiber mat.

The plant fibers include leaf vein plant fibers (e.g., abaca, sisal, agave, etc.), bast plant fibers (e.g., flax, jute, hemp, kenaf, ramie, etc.), woody plant fibers (e.g., plant fibers collected from broad-leaved trees, conifers, etc.), and other plant fibers (coconut shell fiber, oil palm empty fruit bunch fiber, rice straw fiber, wheat straw fiber, bamboo fiber, cotton, etc.). These may use only 1 type and may use 2 or more types together.
Examples of the thermoplastic resin (thermoplastic resin fiber) that can be used include polyolefin resin, polyester resin, polystyrene resin, acrylic resin, polyamide resin, polycarbonate resin, polyacetal resin, and ABS resin. These may use only 1 type and may use 2 or more types together.

The use of the fiber board (FB) is not particularly limited, but it can be used, for example, as an interior material for automobiles, railway vehicles, ships, airplanes, and the like. Among these, automotive applications include door trims, roof trims, package trays, pillar garnishes, and the like. Furthermore, the fiber board can also be used, for example, as an interior material for buildings. For example, it can be used as a door interior material, and a surface material for various types of furniture such as desks, chairs, shelves, and chests of drawers. In addition, it can also be used as a protective member such as a cushioning material, a partition member, and the like.

<Fibrous structure inspection method>
The fiber structure inspection method according to the present embodiment is, for example, a fiber structure inspection method for inspecting the quality of a board-like or mat-like fiber structure (FB), as shown in FIGS. a photographing step of photographing the surface of the fiber structure (FB) while the back surface of the fiber structure (FB) is irradiated with light from the light source (2); The area of the part that is equal to or greater than the threshold value is obtained as the transmission part area (S), and the quality of the fiber structure (FB) is determined based on the size of the transmission part area (S) or the ratio to the surface area of the fiber structure (FB) and the strength of the light source (2), the illuminance of the back surface of the fiber structure (FB), the amount of light incident on the imaging device (3), and the imaging device according to the type of the fiber structure (FB). and a condition changing step of changing at least one of the sensitivity of (3) and the threshold.

As each configuration of the fiber structure inspection method according to the present embodiment, for example, each configuration described in the above-described fiber structure inspection apparatus (1) can be applied. Furthermore, the fiber structure inspection method according to the present embodiment can use, for example, the above-described fiber structure inspection apparatus (1).

It should be noted that the reference numerals in parentheses for each configuration described in the above embodiment indicate the corresponding relationship with the specific configuration described in the examples described later.

Hereinafter, the present invention will be specifically described by way of examples with reference to the drawings. In this embodiment, a fiber board FB containing vegetable fibers such as kenaf and a thermoplastic resin is exemplified as the "fiber structure" according to the present invention. This fiber board FB shall be used as an interior material for vehicles.

(1) Configuration of Fiber Board Inspection Apparatus As shown in FIGS. ), and the brightness of the photographed images P1 and P2 (see FIG. 6) is equal to or higher than a predetermined threshold value. Determination means for determining the quality of the fiber board FB based on the ratio R of the total transmission part area S to the surface area of the fiber board FB, and the type of the fiber board FB (for example, and condition changing means for changing the illuminance and threshold value of the back surface of the fiber board FB according to the use of the fiber board FB (for example, the type of vehicle, the type having different thickness, basis weight, etc.).

The inspection apparatus 1 includes an inspection box 5 which forms a dark room, has a light source 2 arranged at one end thereof, and an imaging device 3 arranged at the other end thereof. The inspection box 5 is formed with an entrance 6 for inserting and removing the fiber board FB between the light source 2 and the photographing device 3 in the dark room. The fiber board FB inserted into the inspection box 5 through the doorway 6 is arranged in an upright state so as to partition the darkroom of the inspection box 5 into two spaces (see FIG. 3). Furthermore, the inspection box 5 is formed with a light-reducing plate inlet/outlet port 7 between the light source 2 and the fiber board FB in the dark room for inserting and removing a light-reducing plate 13, which will be described later. The light-reducing plate 13 inserted into the inspection box 5 through the light-reducing plate entrance 7 is arranged in an upright state so as to divide the darkroom of the inspection box 5 into two spaces (see FIG. 4).
The entrance/exit 6 and the entrance/exit 7 of the light reducing plate are closed with a cover or the like during inspection of the fiber board FB.

As shown in FIGS. 2 and 6, the determination means acquires the photographed image P1 (step S3), binarizes the acquired photographed image P1 (step S4), and in the binarized image P2 The area of the part whose brightness is equal to or higher than a predetermined binarization threshold value is obtained as the transmission part area S, and the ratio R of the transmission part area S to the surface area of the fiber board FB (that is, the transparent area ratio R) is calculated (step S5). Then, the ratio R is compared with the see-through area ratio judgment value (for example, 20%) (step S6), and when the ratio R is equal to or greater than the see-through area ratio judgment value, the product is judged to be defective and the display section notifies the fact. (Step S7). Furthermore, when the ratio R is less than the see-through area ratio determination value, the product is determined to be non-defective, and the effect is reported on the display unit (step S8).

The determination means is constituted by control processing (steps S3 to S8) by the control section 11. FIG. The control processing by the control unit 11 may be realized by either hardware or software, preferably by a microcontroller (microcomputer) having a CPU, a storage device (ROM, RAM, etc.), an input/output circuit, etc. In addition, it can be configured by providing a peripheral circuit such as an input/output interface.

The condition changing means includes a light reducing plate 13 (specifically, a printed glass-like plate) for reducing the illuminance on the back surface of the fiber board FB. One or two or more of the light reducing plates 13 are arranged in the inspection box 5, or not arranged in the inspection box 5, depending on the desired illuminance of the back surface of the fiber board FB (see FIG. 4).

The condition changing means includes a threshold changing means for changing the binarization threshold used when obtaining the transmitting portion area S. FIG. As shown in FIG. 2, the threshold changing means changes a plurality of pre-stored binarization thresholds when a vehicle model number is input by an operator via an input unit such as a keyboard or a touch panel (step S1). A binarization threshold value corresponding to the model number is called out (step S2). This threshold change means is configured by control processing (steps S1 and S2) by the control unit 11 . It should be noted that the threshold changing means can also adjust the binarization threshold according to the brightness of the light source 2 by enabling the brightness of the light source 2 to be measured.
The condition changing means includes judgment value changing means for changing the see-through area ratio judgment value in the photographed image when judging the quality of the fiber board FB. As shown in FIG. 2, when a vehicle model number is input (step S1), the judgment value changing means selects the see-through area ratio determination value corresponding to the vehicle model number from among a plurality of pre-stored see-through area ratio judgment values. A judgment value is called (step S2). This determination value changing means is constituted by control processing (steps S1 and S2) by the control section 11. FIG.

(2) Operation of Fiber Board Inspection Apparatus Next, the operation of the fiber board inspection apparatus 1 configured as described above will be described. In this embodiment, two fiber boards FB1 and FB2 having different uses (vehicle types) are to be inspected. One fiber board FB1 has a width of about 1300 mm, a length of about 900 mm, a thickness of about 2.5 mm, and a basis weight of about 1200 g/m2. The other fiber board FB2 has a width of about 650 mm, a length of about 1000 mm, a thickness of about 2.5 mm, and a basis weight of about 1500 g/m2.

When inspecting the fiber board FB1, as shown in FIG. 5(a), a light reducing plate 13 is placed in the inspection box 5 so that the illuminance of the back surface of the fiber board FB1 is about 1000 lux. Furthermore, by inputting the car model number corresponding to the fiber board FB1, the binarization threshold value (eg, 50 in gradation from 0 to 255) and the see-through area ratio judgment value (eg, 5%) corresponding to the car model number are called. (See steps S1 and S2 in FIG. 2). Under these inspection conditions, the front surface of the fiber board FB1 is photographed while the back surface of the fiber board FB1 is irradiated with light from the light source 2 (photographing step). Next, as shown in FIG. 6, the photographed image P1 is analyzed to determine the transmission area S, and the quality of the fiber board FB1 is determined based on the transparent area ratio R of the transmission area S to the surface area of the fiber board FB1. is determined (determining step; see steps S3 to S8 in FIG. 2).

When inspecting the fiber board FB2 instead of the fiber board FB1, as shown in FIG. 5B, the light reduction plate 13 is taken out from the inspection box 5 so that the illuminance of the back surface of the fiber board FB2 is about 1500 lux. Therefore, the light reducing plate 13 is not arranged in the inspection box 5 (condition changing step). Furthermore, by inputting the car model number corresponding to the fiber board FB2, the binarization threshold value (eg, 15 in gradation from 0 to 255) and the see-through area ratio judgment value (eg, 15%) corresponding to the car model number are called. (Condition changing step; see steps S1 and S2 in FIG. 2). Under these inspection conditions, the front surface of the fiber board FB2 is photographed while the back surface of the fiber board FB2 is irradiated with light from the light source 2 (photographing step). Next, as shown in FIG. 7, the photographed image P1 is analyzed to obtain the transmission area S, and the quality of the fiber board FB2 is determined based on the see-through area ratio R of the transmission area S to the surface area of the fiber board FB2. Judgment (judgment process; see steps S3 to S8 in FIG. 2).

(3) Effect of the Embodiment According to the fiber board inspection device 1 of the present embodiment, the photographing device 3 for photographing the surface of the fiber board FB while the back surface of the fiber board FB is irradiated with light from the light source 2, and the photographing device 3 In the images P1 and P2, the area of the part whose brightness is equal to or higher than a predetermined threshold value is obtained as the transmission area S, and the quality of the fiber board FB is determined based on the ratio R of the transmission area S to the surface area of the fiber board FB. and a condition changing means for changing the illuminance of the back surface of the fiber board FB, the binarization threshold value, and the see-through area ratio determination value according to the type of the fiber board FB. As a result, even if the fiber board FB has a locally different degree of transparency, it is possible to determine the quality of the fiber board FB by obtaining the ratio of the portion of the fiber board FB having relatively high light transmittance to the whole. Furthermore, the inspection conditions can be appropriately changed according to the type of the fiber board FB by the condition changing means. As a result, the quality of the fiber board FB can be inspected according to a certain standard.

Moreover, in this embodiment, the condition changing means comprises a light reducing plate 13 for changing the illuminance of the back surface of the fiber board FB. Thereby, the illuminance of the back surface of the fiber board FB can be effectively changed by the light reducing plate 13 .

Further, in this embodiment, an inspection box 5 forming a dark room is provided, and the inspection box 5 is formed with a doorway 6 for taking in and out the fiber board FB and a light-reducing plate doorway 7 for taking in and out the light-reducing plate 13. ing. As a result, the fiber board FB and the light reducing plate 13 can be easily taken in and out of the inspection box 5 through the entrances 6 and 7 .

According to the fiber board inspection method of the present embodiment, the photographing step of photographing the surface of the fiber board FB while the back surface of the fiber board FB is irradiated with light from the light source 2, and the photographed images P1 and P2 of which the brightness is predetermined. A judgment step of determining the quality of the fiber board FB based on the ratio R of the transmission part area S to the surface area of the fiber board FB, and the type of the fiber board FB and a condition changing step of changing the illuminance of the back surface of the fiber board FB, the binarization threshold value, and the see-through area ratio determination value according to. As a result, even if the fiber board FB has a locally different degree of transparency, it is possible to determine the quality of the fiber board FB by obtaining the ratio of the portion of the fiber board FB having relatively high light transmittance to the whole. Furthermore, the condition changing process can appropriately change the inspection conditions according to the type of the fiber board FB. As a result, the quality of the fiber board FB can be inspected according to a certain standard.

It should be noted that the present invention is not limited to the above-described examples, and may be variously modified examples within the scope of the present invention according to the purpose and application. That is, in the above-described embodiment, an embodiment including the dimming plate 13 for reducing the illuminance on the back surface of the fiber board FB was illustrated, but the present invention is not limited to this. Alternatively, or in addition to the light-reducing plate 13, a light-reducing plate 14 for reducing the amount of light incident on the photographing device 3 may be provided.

In addition, in the above-described embodiment, the illuminance of the back surface of the fiber board FB is changed by the dimmer plate 13, but the present invention is not limited to this. Instead of or in addition to the light plate 13, the distance between the fiber board FB and the light source 2 may be changed to change the illuminance of the back surface of the fiber board FB.

Furthermore, in the above embodiment, the fiber board FB containing plant fibers and thermoplastic resin is exemplified as an inspection target, but the present invention is not limited to this. For example, a fiber mat containing plant fibers and thermoplastic resin fibers is inspected. It may be a target.

The foregoing examples are for illustrative purposes only and are not to be construed as limiting the invention. While the present invention has been described by way of examples of exemplary embodiments, it is understood that the words used in describing and illustrating the invention are words of description and illustration, rather than words of limitation. Changes may be made within the scope of the appended claims without departing from the scope or spirit of the invention in its form, as detailed herein. Although reference has been made herein to specific structures, materials and embodiments in describing the invention, it is not intended that the invention be limited to the disclosure herein, but rather the invention as set forth in the appended claims. It covers all functionally equivalent structures, methods and uses within its scope.

The present invention is not limited to the embodiments detailed above, and various modifications and changes are possible within the scope of the claims of the present invention.

INDUSTRIAL APPLICABILITY The present invention is widely used as a technique for inspecting the degree of transparency of fiber structures such as fiber boards and fiber mats.

1; fiber board inspection device, 2; light source, 3; imaging device, 5; inspection box, 6; entrance, 7; the ratio of the transmission area to the surface area of the fiber board, S; the transmission area.

Claims (8)

A fiber structure inspection device for inspecting the quality of a board-like or mat-like fiber structure,
a photographing device for photographing the surface of the fiber structure while the back surface of the fiber structure is irradiated with light from a light source;
The area of the part whose brightness is equal to or higher than a predetermined threshold value in the photographed image is obtained as the area of the transmission part, and the size of the transmission part area or the ratio to the surface area of the fiber structure is compared with the determination value. Determination means for determining whether the fiber structure is good or bad;
When changing the intensity of the light source, the illuminance of the back surface of the fiber structure, the amount of incident light to the imaging device, or the sensitivity of the imaging device according to the basis weight of the fiber structure, an object to be inspected By inputting information indicating the size of the basis weight of the fiber structure, from among a plurality of threshold values and a plurality of judgment values stored in advance, the threshold value and the judgment value corresponding to the information are called, and the threshold value and the judgment and a condition changing means for changing a value. The fiber structure includes a first fiber structure and a second fiber structure having a higher basis weight than the first fiber structure,
The condition changing means, when changing the illuminance of the back surface of the first fiber structure to the first illuminance according to the first fiber structure, adjusts the basis weight of the first fiber structure. By inputting information indicating the first threshold value and the first determination value are called to change the threshold value and the determination value, and the back surface of the second fiber structure according to the second fiber structure When the illuminance is changed to a second illuminance that is greater than the first illuminance, a second threshold that is smaller than the first threshold is set by inputting information indicating the size of the basis weight of the second fiber structure and a second judgment value larger than the first judgment value to change the threshold value and the judgment value. 3. The fiber structure according to claim 1, wherein the condition changing means comprises a light-reducing plate for changing the illuminance of the back surface of the fiber structure, or a light-reducing plate for changing the amount of light incident on the photographing device. body inspection equipment. An inspection box that forms a darkroom and has the light source arranged at one end thereof and the photographing device arranged at the other end thereof,
The inspection box has a doorway for inserting and removing the fiber structure between the light source and the imaging device in the darkroom, and between the light source or the imaging device in the darkroom and the fiber structure. 4. The apparatus for inspecting a fiber structure according to claim 3, wherein a light-attenuating plate inlet/outlet for inserting and removing the light-attenuating plate is formed. 5. The fiber structure according to any one of claims 1 to 4, wherein the judging means judges that the fiber structure is defective when the total area of the transmitting portions is equal to or greater than a predetermined ratio with respect to the surface area of the fiber structure. inspection equipment. The apparatus for inspecting a fiber structure according to any one of claims 1 to 5, wherein the fiber structure is a fiber board containing plant fibers and thermoplastic resin. A fiber structure inspection method for inspecting the quality of a board-like or mat-like fiber structure,
a photographing step of photographing the surface of the fiber structure while the back surface of the fiber structure is irradiated with light from a light source;
The area of the part whose brightness is equal to or higher than a predetermined threshold value in the photographed image is obtained as the area of the transmission part, and the size of the transmission part area or the ratio to the surface area of the fiber structure is compared with the determination value. a determination step of determining whether the fiber structure is good or bad;
When changing the intensity of the light source, the illuminance of the back surface of the fiber structure, the amount of incident light to the imaging device, or the sensitivity of the imaging device according to the basis weight of the fiber structure, By inputting information indicating the size of the fabric weight of the fiber structure, the threshold and the judgment value corresponding to the information are called from among a plurality of thresholds and a plurality of judgment values stored in advance, and the threshold and the judgment value A method for inspecting a fiber structure, comprising: a condition changing step of changing The fiber structure includes a first fiber structure and a second fiber structure having a higher basis weight than the first fiber structure,
In the condition changing step, when the illuminance of the back surface of the first fiber structure is changed to the first illuminance according to the first fiber structure, the basis weight of the first fiber structure is changed. By inputting information indicating the first threshold value and the first determination value are called to change the threshold value and the determination value, and the back surface of the second fiber structure according to the second fiber structure When the illuminance is changed to a second illuminance that is greater than the first illuminance, a second threshold that is smaller than the first threshold is set by inputting information indicating the size of the basis weight of the second fiber structure 8. The method of inspecting a fiber structure according to claim 7, wherein a second judgment value larger than the first judgment value is called to change the threshold value and the judgment value.

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