JP2008302314A - Optical rice grain sorter - Google Patents

Abstract

[Problem] To provide a multi-light sorter capable of efficiently sorting colored grains, foreign matters and body split grains mixed in a raw material (raw rice grains K) by a single process.
First, second and second optical detectors respectively corresponding to light irradiating units 7 having a first wavelength (green light), a second wavelength (red light) and a third wavelength (near infrared light). 3 CCD sensors (in the CCD camera 8), the colored particles and foreign substances are discriminated based on the received light amount of the first wavelength light, and the body split particles based on the received light amounts of the first wavelength light and the second wavelength light. Further, a foreign matter that cannot be distinguished from a good color product is determined based on the amount of light received by the third wavelength light. When the raw material at the optical detection position P is discriminated as one of these, it is separated from non-defective products by the blast device.
[Selection] Figure 1

Description

  The present invention relates to a rice grain sorter that sorts and removes defective products (defective rice grains) and foreign matters mixed in a raw material (milled rice) by optical means.

  Conventionally, defective products (colored grains such as green grains, shirata, brown grains, etc.) and foreign substances (pebbles, glass pieces, plastic pieces, metal pieces, ceramic pieces, porcelain pieces, etc.) mixed in rice, grains, beans, etc. are selected. As such, a color selection device using optical means is known (Patent Document 1). This device irradiates rice grains and a background plate (reference color plate) with visible light using an incandescent lamp or a fluorescent tube as a light source, and the light quantity difference between the reflected light from the rice grains and the reflected light from the background plate is made into a plurality of wavelength bands. These are divided and detected by the light receiving elements, respectively, and these are selected and removed by utilizing the difference in color exhibited by defective products or foreign materials with respect to non-defective products. However, since this device uses only color as the criterion for discrimination, if the foreign matter is a foreign matter of the same color system as a non-defective product, such as a ceramic piece, that is, a foreign matter that cannot be distinguished from a good quality product, this is selected and removed. I couldn't.

In addition, the reflectance of non-defective products changes from the visible light region to the near-infrared light region and the reflectance of foreign objects such as pottery pieces change. There are foreign matter detection devices that determine foreign matters that cannot be distinguished from good products and rice grain sorting devices incorporating this mechanism (Patent Documents 2 and 3). According to this, foreign matter having the same color as that of the non-defective product or transparent material can be detected.
On the other hand, there is also an optical body split sorter that tries to sort out the rice cracked rice (rice grains having cracks inside), which is a defective product in the polished rice (Patent Documents 4 and 5).

Japanese Patent Laid-Open No. 1-258781 Japanese Patent Laid-Open No. 5-200365 Japanese Patent No. 3079932 JP 2005-265519 A Japanese Patent No. 3642172

However, the conventional optical splitting machine identifies the entire image (overall image) of each rice grain based on the received light data, and when a linear dark shadow data portion is detected in the image, However, the dark shadow caused by the cracked body is misleading with the shadow caused by the germ portion and the shadow caused by the rubbing (scratches on the surface). For this reason, it is an obstacle in completing an optical rice grain sorter that can be said to be a multi-light sorter equipped with the functions of color sorting, foreign matter detection and shell crack sorting.
It is an object of the present invention to provide an optical rice grain sorter that is a multi-light sorter that has an excellent body split sorting function, color sorting, and foreign matter detection function.

The transfer means, the optical detection means, the discrimination means and the sorting means constitute an optical rice grain sorter.
The rice grains as raw materials are aligned and transferred by the transfer means.
The optical detection means includes an irradiation unit and a detection unit. An irradiation part irradiates light with respect to the optical detection position in the fall locus | trajectory of the raw material discharge | released from the transfer means. The detection unit is a CCD camera equipped with a CCD sensor, and detects reflected light and / or transmitted light from each rice grain passing through the optical detection position.
The discriminating unit discriminates colored particles, foreign matter, and body split particles in the raw material based on the reflected light and / or transmitted light detected by the optical detecting unit. Foreign matter includes foreign matter that cannot be distinguished from good quality products.
Then, the sorting unit separates and sorts the colored particles, the foreign matter, and the body split particles determined by the determining unit by means such as an air jet.

  The CCD camera of the detection unit is arranged at a position facing the raw material so that the reflected light and transmitted light from the raw material can be detected at the optical detection position of the trajectory where the raw material falls. At this time, the optical axes of the cameras are arranged so as to be substantially orthogonal to the dropping trajectory. In order to improve the detection accuracy, the reflected light can be received from the back side and the abdomen side (front and back) of the raw material, that is, the CCD camera is placed on the optical axis perpendicular to the fall trajectory with the optical detection position as the center. Sometimes.

  The CCD camera includes a first CCD sensor and a second CCD sensor having high sensitivity in the visible light region and a third CCD sensor having high sensitivity in the near infrared region. These sensors are line sensors and may be color sensors. These sensors may be individually housed in a single CCD camera, or may be housed in a single camera equipped with spectral means such as a dichroic prism. In any case, the first CCD sensor and the second CCD sensor are arranged so that a plurality of wavelength ranges can be individually received in the visible light range.

  The irradiation unit includes a first wavelength light irradiation unit, a second wavelength light irradiation unit, and a third wavelength light irradiation unit. For example, the first wavelength light irradiation unit emits 420 nm to 520 nm blue light or 500 nm to 580 nm green light, the second wavelength light irradiation unit emits 600 nm to 710 nm red light, and the third wavelength light. The irradiation unit irradiates near infrared light of 800 nm to 1000 nm. The first wavelength light irradiator and the second wavelength light irradiator may basically be separated as a wavelength region. If the first wavelength light is red, the second wavelength light is green. Or the reverse of the above, such as blue. However, the light of the third wavelength must be near infrared light. Any of these irradiating parts can be constituted by LEDs.

  The first wavelength light irradiator and the third wavelength light irradiator allow reflected light and / or transmitted light from the raw material at the light detection position to be received by the CCD camera. Specifically, the first wavelength light irradiation unit and the third wavelength light irradiation unit are treated as a pair, and two pairs are arranged on the opposite side of the CCD camera with respect to the falling locus. One pair is a first irradiation unit and the other pair is a second irradiation unit. The first irradiating unit and the second irradiating unit are positioned so that the inner angles of the optical axes of the CCD camera and the optical axis of the CCD camera are substantially the same on one side and the other side of the optical axis of the CCD camera. It arranges in. The inner angle is preferably 70 degrees or less.

When the CCD camera is arranged so as to face the fall locus, these light irradiation units are also arranged at symmetrical positions with the fall locus interposed therebetween. For the first wavelength light irradiator and the third wavelength light irradiator, a background plate having a reflectance comparable to that of a non-defective product is disposed at an opposite position across the fall locus. The
The second wavelength light irradiation unit is disposed at a position where it does not overlap with the optical axis of the CCD camera.

The discriminating means is composed of colored grain / foreign matter discriminating means and foreign matter discriminating means and torso split grain discriminating means that cannot be distinguished from good quality products.
The colored particle / foreign matter determining means determines based on the amount of reflected light and / or transmitted light detected by the first CCD sensor. For example, the determination is made by comparing the color determination threshold value with the amount of reflected light and / or transmitted light detected by the first CCD sensor. Thereby, the particle | grains (piece | piece) from which brightness or a hue differs with respect to a non-defective product are discriminated. However, it is impossible to discriminate foreign matters having lightness or hue equivalent to those of non-defective products.

  The foreign matter discriminating means indistinguishable from the good quality product calculates the ratio or difference between the detected light amounts based on the detected light amount signal of either the first CCD sensor or the second CCD sensor and the detected light amount signal of the third CCD sensor. Is compared with the threshold value for foreign matter determination. This discrimination method uses the characteristic that the reflectance from the non-defective product and the foreign matter is greatly different in the case of visible light, but is small in the case of near infrared light. That is, based on the detected light amount of the third CCD sensor that detects near-infrared light and the detected light amount of the first CCD sensor or the second CCD sensor that detects visible light of green or red, the ratio or difference between them is calculated. An operation for comparing the result with the threshold value in each case is performed.

The torso split discrimination means creates a first rice grain image from the reflected light and / or transmitted light detected by the first CCD sensor, creates a second rice grain image from the transmitted light detected by the second CCD sensor, The light amount difference between the first rice grain image and the second rice grain image is calculated (for example, subtracted).
The first rice grain image is reflected light and / or transmitted light from the light irradiation unit of the first wavelength. As described above, the light irradiation unit of the first wavelength sandwiches the optical axis of the CCD camera. Since it is symmetrically arranged on the other side and the other side, the shadow caused by one irradiation part caused by the body crack is canceled by the bright part and transmitted light by the other irradiation part, and eventually the first CCD sensor detected The shadow of the shell crack does not appear in the first rice grain image formed from the reflected light and transmitted light. Other shadows appear due to the germ and rubbing parts.

On the other hand, the second rice grain image does not overlap with the optical axis of the CCD camera, that is, from the light irradiation unit of the second wavelength disposed at the position where the transmitted light from the raw material at the light detection position is received by the CCD camera. Since it was created based on light (transmitted light), the shadow caused by the torn surface appears clearly.
The light of the second wavelength irradiated from the position where it does not overlap with the optical axis of the CCD camera is divided into reflected light and transmitted light on the surface of the rice grain, but the reflected light is opposed to, for example, the CCD camera on the back side. Out of the light receiving range, only the transmitted light is detected by the CCD camera on the ventral side. In a CCD camera that receives transmitted light, light is refracted or scattered in another direction by the body split surface, and a clear shadow appears at a position corresponding to the body split. In addition, other shadows caused by the germ portion and the rubbing portion also appear.
Therefore, by calculating (for example, subtracting) the light amount difference between the first rice grain image and the second rice grain image, it is possible to discriminate the body split grain.

  By being a multi-light sorter, it is possible to efficiently sort colored grains, foreign matters (including those that cannot be distinguished from good quality products), and torn split grains. As a result, it is possible to sort out and remove colored grains, foreign matters, and split body grains from non-defective products in a so-called one-time manner, and efficient rice grain sorting can be performed.

It is also easy to adopt a configuration in which the reflected light and transmitted light from the back side and the ventral side of the rice grain are detected simultaneously, and the sorting accuracy can be further improved.
Since the structure of color sorting, foreign matter sorting, and body split grain sorting function is integrated, the entire optical rice grain sorter is more than the equipment and combination facilities that combine these sorters. It becomes a miniaturized product without waste. In addition, maintenance becomes easy.

  1 and 2 are longitudinal sectional views of an embodiment relating to the optical rice grain sorter 1 of the present invention. In Example 1 (FIG. 1), the CCD camera 8 is made of raw materials (mostly raw rice grains K). It is arranged only on the abdominal surface side of the fall locus G, and is arranged almost symmetrically on both sides of the fall locus G in the second embodiment (FIG. 2).

  In Example 1 (FIG. 1), the optical rice grain sorter 1 includes a raw material tank 2 for storing raw materials, and a vibration feeder 4 for sequentially sending the raw materials discharged from the raw material tank 2 to an inclined chute 3 to be described later. A transfer means 5 comprising the inclined chute 3 inclined downward is constituted. In this embodiment, the downward inclination angle of the inclined chute 3 is 60 degrees. A plurality of grooves 3a (FIG. 3 (a)) are formed adjacent to the inclined surface of the inclined chute 3 along the flow direction, and the raw rice grains K are caused to flow while being aligned in the length direction of the rice grains. It is. In this embodiment, the width W of the groove 3a is 3.3 millimeters corresponding to the width dimension of the rice grain K. In the vicinity of the lower end portion of the inclined chute 3, an optical detection means 6 and a sorting means 6a are sequentially arranged at a position along the fall trajectory G of rice grains.

  The optical detection means 6 forms an irradiation unit 7 on one side of the optical detection position P on the fall locus G and a CCD camera 8 on the other side (FIG. 1). The optical detection positions P are continuous in a horizontal line corresponding to the arrangement of the grooves 3 a in the chute 3. The irradiation unit 7 is different from the first wavelength light irradiation unit 9a that irradiates the optical detection position P with the first wavelength light (green light in this embodiment), and the first wavelength light irradiation unit 9a. The light irradiation unit 9b has a second wavelength that emits colored light (red light in this embodiment) and the light irradiation unit 10 has a third wavelength that emits near-infrared light. The first wavelength light irradiation unit 9a and the third wavelength irradiation unit 10 form a first irradiation unit 12 and a second irradiation unit 13 as a pair, which are symmetrical with respect to the optical axis 11 of the CCD camera 8. Furthermore, in this embodiment, they are also arranged on the opposite side with the material drop locus G in between. Therefore, it is set as the arrangement which irradiates both the back part and abdominal part of a raw material.

  The inner angle α1 formed by the optical axis (optical path) 12a of the first irradiation unit 12 and the optical axis 11 of the CCD camera 8, the optical axis (optical path) 13a of the second irradiation unit 13, and the optical axis 11 of the CCD camera 8 Are arranged at positions where the inner angle α2 formed by the two becomes substantially the same angle. In this embodiment, the inner angle α1 and the inner angle α2 are both 25 degrees. This angle is preferably 70 degrees or less. Even if the inner angles α1 and α2 are slightly different due to the assembly error of the CCD camera 8 and the irradiating unit 7, both angles are included in the range of the substantially same angle. On the other hand, the light irradiation unit 9b having the second wavelength is arranged at a position where the optical axis 9ba of the irradiation light of the light irradiation unit 9b having the second wavelength does not overlap with the optical axis 11 of the CCD camera 8. To do. The CCD is an abbreviation for “Charge Coupled Devices”.

  In the second embodiment (FIG. 2), the CCD camera 8 is arranged substantially symmetrically on both sides of the fall locus G so that the raw material at the optical detection position P can be measured from both the back side and the ventral side. Since the configuration other than 8 is the same as that of the first embodiment (FIG. 1), the same reference numerals are given to the same components, and the description so far is used, and the same applies to the following. As the explanation proceeds.

  The first irradiating unit 12, the second irradiating unit 13, and the light irradiating unit 9b having the second wavelength can each irradiate light having directivity with respect to the optical detection position P. For example, a line laser light emitter may be used, but more preferably, an LED (light emitting diode) with little variation in irradiation light in the left-right direction may be used. When the LED is used, each LED is composed of an LED element 13b and a condenser lens 13c as shown in FIG. 1, and the light emitted from the LED element 13b is broken by a broken line shown in FIG. In this way, the light is condensed and irradiated to the optical detection position P in a horizontal line.

  The light emitting unit 9a having the first wavelength using an LED uses green light having a wavelength of 500 nm to 580 nm, and the LED element used in this example has a center wavelength of 520 nm and a half width of 50 nm. Similarly, the second wavelength light irradiation unit 9b using an LED uses red light of 600 nm to 710 nm, and the LED element used in this example has a center wavelength of 630 nm and a half width of 18 nm. . The light irradiation unit 10 of the third wavelength used near-infrared light of 800 nm to 1000 nm, and the LED element used in this example had a center wavelength of 850 nm and a half-width of 30 nm.

  In the present invention, the light irradiation unit 9a having the first wavelength and the light irradiation unit 9b having the second wavelength may irradiate light of different colors (different wavelength regions) as described above. In addition to the combination of green light and red light as in the example, it may be combined with blue light of 420 nm to 520 nm. The light amount adjustment of the first wavelength light irradiation unit 9a and the second wavelength light irradiation unit 9b will be described later.

  As shown in FIG. 4, the CCD camera 8 includes a lens 14, a dichroic prism (spectral means) 15, a color CCD line sensor (first CCD sensor) 16a, and a color CCD line sensor (in order from the light incident direction). A second CCD sensor) 16b and a near-infrared CCD sensor (third CCD sensor) 17 are provided.

Of the light received from the rice grain K at the optical detection position P by the spectral action of the dichroic prism (spectral means) 15, the first CCD sensor 16a reaches the first wavelength light (green light), and reaches the second CCD sensor 16b. Of the light received from the rice grain K, light of the second wavelength (red light) arrives. The light of the second wavelength is light that has passed through the rice grain K. The third CCD sensor 17 reaches the third wavelength light (near infrared light) among the light received from the rice grain K.
The outputs of the first, second and third CCD sensors 16a, 16b and 17 are respectively connected to the discrimination means 18, and signal processing based on the output (detection signal) is performed.

  Each of the first, second, and third CCD sensors 16a, 16b, and 17 is composed of a plurality of light receiving elements connected in a line shape (in a horizontal row), as conceptually shown in FIG. A plurality of light receiving elements are assigned to each of the plurality of grooves (channels) 3a of the inclined chute 3 to form pixels, and the reflected / transmitted light from the rice grains K falling from the grooves (channels) 3a is in units of pixels. It is designed to receive light. Further, by integrating the lens 14, the dichroic prism 15, and the color CCD line sensors 16a, 16b, 17 and the like, the reflected light and / or transmitted light of the three color light (three wavelengths) detected from the same rice grain K can be obtained. When forming a rice grain image by the discrimination processing based on the above, no deviation occurs between the rice grain images.

  In this embodiment, the sorting means 6a is a high-pressure air blowing means for blowing high-pressure air like an air gun, but a plate spring type using a solenoid may also be used. . A plurality of high-pressure air blast means are provided with one blast port for each of the grooves (channels) 3a so as to blow high-pressure air toward the drop locus G below the optical detection position P. The nozzle 6b formed by connecting the nozzle holes 6c is provided (FIG. 3B). Each jet port 6c of the nozzle 6b is connected to each electromagnetic valve via a pipe line, and each electromagnetic valve communicates with a high-pressure air source.

Each of the solenoid valves is connected to the ejector valve drive circuit 25 (FIG. 5), and receives a blast signal from the ejector valve drive circuit 25 to instantaneously open and close the valve. Thereby, high-pressure air such as an air gun is instantaneously blown, and defective particles are removed from the drop locus G and sorted.
In FIGS. 1 and 2, reference numeral 25a denotes a background plate, which is disposed on the optical axis 11 of the CCD camera 8 so as to face the opposite side of the CCD camera 8 with respect to the falling locus, and its surface is a good product in the raw rice grain K. It has the same reflectivity.

  As shown in FIG. 5, the discriminating means 18 includes an input / output circuit (I / O) 19 connected to each of the first, second and third CCD sensors 16a, 16b and 17 incorporated in the CCD camera 8. A signal processing circuit 20 connected to the input / output circuit (I / O) 19, a central processing unit (CPU) 21 and a read / write storage unit (RAM) 22 connected to the signal processing circuit 20, and the central processing unit 21 includes a read-only memory (ROM) 23 and an input / output circuit (I / O) 24 connected to 21. The input / output circuit 24 is connected to the ejector valve drive circuit 25. In the present embodiment, the discrimination unit 18 a refers to the signal processing circuit 20, the central processing unit 21, the read / write storage unit 22, and the read-only storage unit 23.

Next, the operation of the present invention will be described.
The raw material (raw material rice grain K) is sequentially supplied from the raw material tank 2 to the upstream side of the inclined chute 3 by the vibration action of the vibration feeder 4 which is the transfer means 5. Each raw rice grain K supplied to the inclined chute 3 enters the groove 3a, flows down while the direction (posture) of the rice grains is aligned in the length direction, and is discharged from the terminal portion. Each released raw rice grain K falls in the posture along the fall trajectory G and passes through the optical detection position P. When the raw rice grains K pass through the optical detection position P, the green light is emitted from the first wavelength light irradiation unit 9a. Light and red light from the second wavelength light irradiation unit 9b and near-infrared light from the third wavelength light irradiation unit 17 are irradiated.

  The CCD camera 8 receives reflected / transmitted light from the raw material at the optical detection position P. Among them, the first wavelength light (green light) and the third wavelength light (near infrared light) are close to both sides of the CCD camera 8 as the first irradiation unit 12 and the second irradiation unit 13 as described above. Therefore, the reflected light and the transmitted light are received. The reflected light is due to the light from the irradiating part on the same side as the CCD camera 8 with respect to the falling locus G, and the transmitted light is due to the light from the irradiating part on the opposite side of the CCD camera 8 with respect to the falling locus. It is.

  The light of the second wavelength (red light) is irradiated from a position where the irradiation unit 9b does not overlap with the optical axis of the CCD camera, so the reflected light of the reflected light and transmitted light on the surface of the rice grain is the light receiving range of the CCD camera 8. And only transmitted light is received. In this sense, the second wavelength light irradiation unit 9b needs to be arranged on the opposite side of the CCD camera 8 that receives the transmitted light with the fall locus G interposed therebetween (FIGS. 1 and 2).

  Detection signals generated by receiving light by the first, second, and third CCD sensors 16a, 16b, and 17 are sequentially sent to the signal processing circuit 20 via the I / O 19 of the discrimination means 18, and the signal processing is performed. The circuit 20 calculates a light amount at the optical detection position P (on one horizontal line) or forms a rice grain image (image) based on the sequentially detected reflected light and transmitted light.

(Color discrimination)
Based on the detection signal relating to the first wavelength received by the first CCD sensor 16a, the amount of received light is calculated for each passage of the raw material, and the threshold value recorded or set in advance in the RAM 22, that is, the first value from the background plate 25a. Together with the amount of light received for one wavelength, it is sent to the CPU 21 and the two amounts of received light are compared (FIG. 6). When the amount of light received from the first CCD sensor 16a is smaller than the threshold value, the raw materials (grains, pieces) that have passed through the optical detection position P are determined as colored grains / foreign matter.
Since this discrimination method is based on the color (lightness), a foreign object having the same color (lightness) as that of a good product cannot be discriminated. For this discrimination, a discrimination method using light of the third wavelength (near infrared light) is used as follows.

[Determination of foreign matter that cannot be distinguished from quality products]
As shown in FIG. 7, in the near-infrared light region where the wavelength region is 800 to 1000 nm, the reflectance of ceramics and white pellets is about 0.65, which is almost the same as that of rice grains. On the other hand, in blue light or green light region with a wavelength range of 450 to 500 nm, the reflectance of rice grains is low at about 0.4 to 0.5, whereas the reflectance of ceramic is about 0.9, the reflectance of white pellets Is a high reflectance of about 0.7. This characteristic is used to detect foreign matters that cannot be distinguished from non-defective products.
That is, the detection signal of either the first or second line sensor 16a, 16b and the detection signal of the third CCD line sensor 17 are sequentially sent to the signal processing circuit 20 via the I / O 19 of the discrimination means 18, where Each received light amount is converted into data and temporarily stored in the RAM sequentially. Next, the CPU 21 retrieves the received light amount data from the RAM at a predetermined timing and stores it in the ROM 23 to store the received light amount of one of the first and second line sensors 16 a and 16 b and the third CCD line sensor 17. The ratio (FIG. 8, Y value) or difference with the amount of received light is calculated, and the result is compared with a threshold value for discrimination set in advance and stored in the RAM or ROM to discriminate whether it is a non-defective product or a foreign material. (FIG. 9).

(Distinction of torn grain)
Based on the detection signal relating to the second wavelength (red light) received by the second CCD sensor 16b, a first rice grain image (image) at the optical detection position P (on the horizontal line) is formed. On the other hand, similarly, a second rice grain image at the optical detection position P (on the horizontal line) is formed based on a detection signal relating to the first wavelength (green light) received by the first CCD sensor 16a.
Each rice grain image created based on the transmitted light of the second wavelength (red) is shown in FIG. 10 (a), in which the crack part, the germ part, and the skin misalignment part appear in the whole shape of the rice grain. 1st rice grain image (there is a crack part, an embryo part, and a skin shift part). The first rice grain image is sequentially stored in the RAM 22.

On the other hand, the first wavelength light (green light) scanned by the first CCD sensor 16a similarly forms a rice grain image at the optical detection position P (on the horizontal line) based on the detection signal.
As shown in FIG. 10 (b), each rice grain image created based on the reflected / transmitted light of the first wavelength has no cracks in the entire shape of the rice grain, and the skin part and skin misalignment. It becomes the 2nd rice grain image in which the image of only the part appeared. The second rice grain image 2 is also stored in the RAM 22 sequentially.

  As described above, the cracked portion does not appear (is not detected) in the second rice grain image because the irradiation light from the first irradiation unit 12 and the second irradiation unit 13 is centered on the optical axis 11 of the CCD camera 8. This is because dark shadows caused by light being refracted at the crack portion cancel each other out from the same angle (the inner angle α1 = inner angle α2) with respect to the rice grains (trunk grains) K at the optical detection position P, On the other hand, this is because when the rice grains (trunk grains) K are irradiated with light from only one oblique direction, the light is refracted at the cracked portion and a dark shadow appears on the surface of the rice grains.

  Next, the first rice grain image and the second rice grain image are read from the RAM 22, and the second rice grain image (the germ part and the skin is determined from the amount of light of the first rice grain image (the crack part, the germ part and the skin shift part). A subtraction process for subtracting the amount of light (only the shift portion) is performed (FIG. 11). By this subtraction process, both the germ portion and the skin shift portion are canceled and canceled, so that only the crack portion remains in the obtained image. As a result, it is possible to extract (specify) a crack image of only the torso part.

  The light amounts of the first wavelength light irradiation unit 9a and the second wavelength light irradiation unit 9b are subtracted between the first rice grain image and the second rice grain image as shown in FIG. The image of the germ portion, the image of the skin deviation portion, and the rice grain outline are canceled out to each other so as not to remain in the image as much as possible, and it is necessary to adjust in advance so that only the crack image remains. In the unlikely event that the image of the germ part, the image of the skin deviation part, and the image of the rice grain outline remain thin, for example, a binarization process is performed according to a threshold value that distinguishes the light quantity of the crack image, and only the crack image is obtained. To clarify.

  The subtraction process shown in FIG. 11 will be described in more detail with reference to FIGS. For convenience of explanation, each rice grain cross section (continuous imaging) of the first rice grain image (crack part, embryo part and skin misalignment part) and second rice grain image (only germ part and skin misalignment part) shown in FIG. The amount of light (waveform) in the data column) is taken as a graph, and the subtraction process will be specifically described using this amount of light (waveform).

First, FIG. 13 (1) shows the light quantity (waveform) in each rice grain cross section of the first rice grain image and the second rice grain image, and as shown in the figure, cracks, embryo parts and skin are shown in the waveform. A shift portion is detected.
Next, the difference between the two waveforms shown in (1) above is calculated, and as a result, the waveform shown in FIG. 13 (2) is obtained. Thereby, the sprouting waveform corresponding to the crack portion is detected by the germ portion and the skin shift portion canceling each other in each rice grain image.

Next, processing for increasing the waveform level of the cracked portion shown in (2) above from the minus region to the plus region is performed, and the waveform obtained by this processing is shown in FIG. 13 (3).
Furthermore, the waveform shown in the above (3) is subjected to differential processing to clarify the waveform of the crack portion, and the waveform obtained by this processing is shown in FIG. 13 (4). In this way, the light amount subtraction process for the first rice grain image and the second rice grain image is performed in units of each rice grain cross section (a sequence of continuous imaging data), leaving only the crack image.

  Next, the CPU 21 counts the number of pixels of the crack image left as described above. The number of counts is compared with a threshold value for discriminating the body splitting previously set in the ROM 23, that is, the number of continuous pixels for determining the torso split part. ) On the other hand, if the count number is less than the threshold value, the body split portion is canceled and this is not determined as the body split grain.

As described above, when the colored material, the foreign material (including the foreign material that cannot be distinguished from the good color), or the body split particle is determined with respect to the raw material at the optical detection position P, the CPU 21 passes through the I / O 24. The ejector valve drive circuit 25 outputs a signal to the ejector valve drive circuit 25, and the ejector valve drive circuit 25 selects the selecting means 6a (high-pressure air blast means) corresponding to the grooves (channels) 3a in which the colored particles and foreign matter are detected. The electromagnetic valve is operated with a predetermined delay time to generate a blast signal to operate the solenoid valve, and the corresponding particles are ejected from the fall locus G by a blast (air gun) from the blast port 6c of the nozzle 6b corresponding thereto. Sort out foreign material and body split grains.
At this time, the center position or the like of the split body grains is detected by a known method (for example, Japanese Patent No. 3722354), and a signal is output to the solenoid valve corresponding to the detected center position to output the center position of the split body grains. May be selected to more surely sort the torn grains.

  As described above, the present invention exhibits excellent performance as a so-called multi-light sorting rice grain sorter. In particular, it is possible to discriminate the torn cracked grain because even if the germ part or skin misalignment part is in the rice grain in addition to the crack part, the image of the germ part or skin misalignment part can be canceled to obtain a crack image of only the crack part. When discriminating torso split grains, it is not possible to mistakenly distinguish normal grains that do not have cracks from the germ and skin misalignment images as torso split grains. , Improve product yield.

The embodiment has been described above.
In the embodiment, the CCD line sensor is separated for each wavelength range to be used, but a filter that passes the first wavelength, the second wavelength, and the third wavelength with respect to one CCD line sensor. The three types of filters are arranged for each light receiving element with respect to a row of light receiving elements (pixels) in the CCD line sensor as shown in FIG. It can have a structure in which light of a wavelength and a third wavelength is received by each unit light receiving element. Alternatively, as shown in FIG. 14B, the CCD line sensor is provided with three light receiving element arrays, and three types of filters are assigned to each light receiving element array, and the first wavelength, the second wavelength, and the third wavelength. The light can be received by each unit light receiving element array.
Further, as one CCD line sensor, the irradiation unit 7 side alternately irradiates light of the first, second and third wavelengths, receives light by each lighting, and based on the received light data, It is also possible to adopt a configuration for performing the determination process.

The longitudinal cross-sectional view which showed typically the optical rice grain sorter (Example 1). The longitudinal cross-sectional view which showed typically the optical rice grain sorter (Example 2). (A) is sectional drawing of an inclination chute, (b) is the front view which showed the optical detection position typically. The side view which shows schematic structure in a CCD camera. The block diagram of a discrimination means. The figure which showed the discrimination | determination principle of the colored grain. The figure which showed the reflectance of the rice grain and foreign material in the near-infrared light area | region of wavelength 800-1000nm vicinity from visible light area | region. The flowchart of a foreign material discrimination | determination. The figure which showed the principle which discriminate | determines the foreign material which cannot be distinguished with a rice grain and color. The figure which showed the outline | summary of the image acquisition in trunk | drum split grain discrimination. The figure which showed the outline | summary of the crack detection in trunk | drum split grain discrimination. The figure for demonstrating the acquired image in trunk split grain discrimination. The figure which showed the procedure of the crack signal acquisition. FIGS. 4A and 4B are front views showing other configurations of the CCD sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical rice grain sorter 2 Raw material tank 3 Inclination chute 3a Groove 4 Vibrating feeder 5 Transfer means 6 Optical detection means 6a Sorting means 6b Nozzle 6c Blow hole 7 Irradiation part 8 CCD camera 9a Light irradiation part 9b of 1st wavelength 2nd wavelength Light irradiation unit 10 Third light irradiation unit 11 Optical axis 12 of CCD camera First irradiation unit 12a Optical axis 13 of first irradiation unit Second irradiation unit 13a Optical axis 13b of second irradiation unit LED element 13c Lens 14 Lens 15 Dichroic prism (spectral means)
16a First CCD sensor 16b Second CCD sensor 17 Third CCD sensor 18 Discriminating means 18a Discriminator 19 Input / output circuit (I / O)
20 signal processing circuit 21 central processing unit (CPU)
22 Read / write memory (RAM)
23 Read-only memory (ROM)
24 I / O circuit (I / O)
25 Ejector valve drive circuit 25a Background plate K Raw material rice grain P Optical detection position

Claims (7)

Transfer means for aligning and transferring each rice grain of raw material;
An irradiation unit for irradiating light to the optical detection position in the fall trajectory of the rice grain emitted from the transfer means, and a CCD sensor for detecting transmitted light and reflected light from each rice grain passing through the optical detection position are provided. An optical detection means comprising a detection unit for optical detection by providing a CCD camera; and a discrimination means for discriminating colored grains, foreign matter and body split grains in the raw material based on transmitted light and reflected light detected by the optical detection means;
Sorting means for sorting the colored particles, foreign matter and body split grains determined by the determining means;
An optical rice grain sorter having
The CCD camera includes a first CCD sensor and a second CCD sensor having high sensitivity in the visible light region that individually receive light in a plurality of wavelength regions, and a third CCD sensor having high sensitivity in the near infrared region,
The irradiation unit includes a light irradiation unit having a first wavelength in the visible light region, a light irradiation unit having a second wavelength, and a light irradiation unit having a third wavelength in the near-infrared light region. Are arranged so that reflected light and / or transmitted light reach the CCD camera,
Based on the amount of light detected by the first CCD sensor or the second CCD sensor, color particles and foreign matter are discriminated from the raw material,
The body split grain is determined by calculating each image based on the detection values of the first CCD sensor and the second CCD sensor,
An optical rice grain sorter comprising means for discriminating foreign matter that cannot be distinguished from non-defective products based on detection values of a third CCD sensor. Transfer means for aligning and transferring each rice grain of raw material;
An irradiation unit for irradiating light to the optical detection position in the fall trajectory of the rice grain emitted from the transfer means, and a CCD sensor for detecting transmitted light and reflected light from each rice grain passing through the optical detection position are provided. An optical detection means comprising a detection unit for optical detection by providing a CCD camera;
Discriminating means for discriminating colored grains, foreign matter and body split grains in the raw material based on the transmitted light and reflected light detected by the optical detecting means,
Sorting means for sorting the colored particles, foreign matter and body split grains determined by the determining means;
An optical rice grain sorter having
The CCD camera includes a first CCD sensor and a second CCD sensor having high sensitivity in the visible light region for individually receiving light in a plurality of wavelength regions, and a third CCD sensor having high sensitivity in the near infrared region, and the camera optical axis. Is placed almost orthogonal to the fall trajectory at the optical detection position on the fall trajectory where the raw material falls,
The irradiation unit includes a light irradiation unit having a first wavelength in the visible light region, a light irradiation unit having a second wavelength, and a light irradiation unit having a third wavelength in the near-infrared light region, and the light irradiation unit having the first wavelength; The third wavelength light irradiating unit makes a pair, and two pairs on the same side with respect to the fall locus, one pair on one side and the other side sandwiching the optical axis of the CCD camera as the first irradiating unit and the second irradiating unit. The inner angles formed by the optical axes of the first irradiating unit and the second irradiating unit that are disposed and irradiate the optical detection position and the optical axis of the CCD camera are substantially the same, and the first irradiating unit and the second irradiating unit The irradiation unit is arranged on the opposite side across the fall locus, and a background plate set to reflect the same degree as the non-defective product is arranged at the opposite position across the fall locus, and the light of the second wavelength The irradiating unit is arranged at a position where it does not overlap with the optical axis of the CCD camera,
The discriminating means comprises a colored particle / foreign matter discriminating means and a foreign matter discriminating means and a body split grain discriminating means that cannot be distinguished from good quality products,
The colored particle / foreign matter discriminating means includes a discriminating unit for discriminating the colored particles / foreign matter in comparison with a coloring judgment threshold that sets the amount of reflected / transmitted light detected by the first CCD sensor,
The foreign matter discriminating means that cannot be distinguished from non-defective color is calculated based on the detected light amount signal of either the first CCD sensor or the second CCD sensor and the detected light amount signal of the third CCD sensor, and compares this with a threshold value for determining the foreign matter. And a discriminator for discriminating between foreign products that cannot be distinguished from good products and good quality products,
The body split discriminating means creates a first rice grain image from the reflected light / transmitted light detected by the first CCD sensor, and the second rice grain from the transmitted light from the irradiation section of the second wavelength detected by the second CCD sensor. An optical rice grain sorter comprising: a discriminating unit for discriminating a torn grain by creating an image and specifying a crack portion in the rice grain by subtracting the first rice grain image and the second rice grain image . Transfer means for aligning and transferring each rice grain of raw material;
An irradiation unit for irradiating the optical detection position on the falling locus of the rice grain emitted from the transfer means and a CCD for detecting transmitted light and reflected light from each rice grain passing through the optical detection position An optical detection means comprising a CCD camera equipped with a sensor and detecting optically;
Discriminating means for discriminating colored grains, foreign matter and body split grains in the raw material based on the transmitted light and reflected light detected by the optical detecting means,
Sorting means for sorting the colored particles, foreign matter and body split grains determined by the determining means;
An optical rice grain sorter having
The CCD camera is a position facing the back side and the abdomen side of the raw material at the optical detection position of the trajectory where the raw material falls, and the optical axis of the CCD camera intersects the dropping trajectory substantially at a right angle. And a first CCD sensor and a second CCD sensor having high sensitivity in the visible light region that individually receive light in a plurality of wavelength regions, and a third CCD sensor having high sensitivity in the near infrared region.
The irradiation unit includes a first wavelength light irradiation unit and a second wavelength light irradiation that irradiates light of different colors from among 420 nm to 520 nm blue light, 500 nm to 580 nm green light, and 600 nm to 710 nm red light. And a third wavelength light irradiation unit that irradiates near-infrared light of 800 nm to 1000 nm, and the first wavelength light irradiation unit and the third wavelength light irradiation unit are on the same side with respect to the fall trajectory. The inner angles formed by the optical axes of the CCD camera and the optical axes of the CCD camera are set to be substantially the same, one pair on one side and the other side of the optical axis of the CCD camera. The first irradiation unit and the second irradiation unit are disposed, and the first wavelength light irradiation unit and the third wavelength light irradiation unit are also arranged on the opposite side of the side where the falling locus is provided, A first wavelength light irradiator and a third wavelength light irradiator; A background plate having a reflectance comparable to that of a non-defective product is disposed at the opposite position across the lower locus, and the second wavelength light irradiation unit is disposed at a position where it does not overlap with the optical axis of the CCD camera. Set up
The discriminating means comprises a colored particle / foreign matter discriminating means and a foreign matter discriminating means and a body split grain discriminating means that cannot be distinguished from good quality products,
The colored particle / foreign matter discriminating means includes a discriminating unit for discriminating the colored particles / foreign matter in comparison with a coloring judgment threshold that sets the amount of reflected / transmitted light detected by the first CCD sensor,
The foreign matter discriminating means that cannot be distinguished from the non-defective color is calculated based on the detected light amount signal of either the first CCD sensor or the second CCD sensor and the detected light amount signal of the third CCD sensor, and compares this with the threshold value for determining the foreign matter. And a discriminator that discriminates foreign objects that cannot be distinguished from non-defective products and good-quality products,
The body split discriminating means creates a first rice grain image from the reflected light / transmitted light detected by the first CCD sensor, and the second rice grain from the transmitted light from the irradiation section of the second wavelength detected by the second CCD sensor. An optical rice grain sorter comprising: a discriminating unit for discriminating a torn grain by creating an image and specifying a crack portion in the rice grain by subtracting the first rice grain image and the second rice grain image .   In the foreign matter discriminating means that cannot be distinguished from non-defective products, the calculation based on the detected light amount signal of either the first CCD sensor or the second CCD sensor and the detected light amount signal of the third CCD sensor is performed by the ratio of the detected light amount of the both signals The optical rice grain sorter according to claim 2 or 3, wherein a difference is obtained and compared with a corresponding threshold value.   The optical rice grain sorter according to claim 3 or 4, wherein the inner angle is 70 degrees or less.   The first CCD sensor and the second CCD sensor are color CCD line sensors, and the CCD camera receives reflected light and transmitted light detected from the optical detection position as light of the first wavelength, light of the second wavelength, and second light. The optical rice grain sorter according to any one of claims 1 to 5, further comprising a spectroscopic unit that splits light into three wavelengths and separately enters the first CCD sensor, the second CCD sensor, and the third CCD sensor. .   The optical rice grain sorter according to any one of claims 1 to 6, wherein the first wavelength irradiation unit, the second wavelength irradiation unit, and the third wavelength irradiation unit are configured by LEDs.

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