JPWO2012005350A1 - Non-destructive measuring device for fruits and vegetables - Google Patents

Abstract

Provided is a non-destructive measuring apparatus for fruits and vegetables which can improve the accuracy of measurement values of the characteristics of fruits and vegetables by suppressing the influence of external light on the received light and can simultaneously measure light in a plurality of wavelengths. A light emitting unit 1 for irradiating light, a light receiving unit 2 for receiving diffused light, and a processing means for calculating a transmitted light amount from the diffused light detected by the light receiving unit and calculating an evaluation amount of the fruit and vegetable from a calibration curve. In the nondestructive measuring apparatus A, a plurality of optical sensors 61 and 62 disposed on the surface of the substrate 6, a plurality of optical filters 51 and 52 individually disposed in the vicinity of each optical sensor, and the periphery of the optical sensor. Filter holding unit 5 that holds the optical filter while individually enclosing, optical transmission cables 31 and 32 that transmit the diffused light detected by the light receiving unit to each optical filter, and filter holding that surrounds each end of the optical transmission cable And a cable support 4 that holds each end of the optical transmission cable.

Description

  The present invention relates to an apparatus for measuring characteristics such as sugar content or ripeness without destroying fruits and vegetables.

  As a device for measuring the characteristics of fruit and vegetables without destroying them, there is a light transmission type measuring device that receives light transmitted through the fruits and vegetables and measures the absorbance absorbed inside the fruits and vegetables (see Patent Documents 1 and 2). ). In the light transmission type measuring device, since the light projecting unit and the light receiving unit are provided opposite to the opposite sides centering on the fruits and vegetables, the entire device has to be fixed and does not move easily. . Therefore, the measuring apparatus has been used exclusively for fruits and vegetables that are transported on a conveyor in the fruits and vegetables market.

  On the other hand, in order to make the fruit and vegetable measuring device movable, the light projecting part and the light receiving part are arranged so as to be close to each other, and the light reflected from the surface of the fruit and vegetables is received or diffused inside the fruit and emitted. A light diffusion type measuring device for receiving diffused light that has been developed has been developed (see Patent Document 3 or 4). This type of measuring device uses an LED as a projection light source, irradiates near-infrared rays of a predetermined wavelength with this LED, and calculates characteristics (for example, sugar content and maturity) to be measured from the reflectance or transmittance of the wavelength. It was something to do. In addition, as a method for measuring the amount of transmitted light emitted from the fruits and vegetables and judging the characteristics of the fruits and vegetables, there is a correlation between measured values and measured values (absorbance measurement values) for the fruits and vegetables to be measured. A calibration curve based on this was prepared in advance, and the characteristics (evaluation amount) of fruits and vegetables were calculated by comparing the measured values of reflected light or diffused light with the calibration curve (see Patent Document 5).

JP-A-6-186159 JP 2002-122536 A JP-A-5-288664 JP 2000-88747 A JP 2006-226775 A

  However, in the above-described light reflection type or light diffusion type fruit and vegetable measuring apparatus, the light source that irradiates the fruit and vegetable is set to a specific wavelength, so the wavelength of the light that is irradiated according to the characteristics of the fruit and vegetable to be measured is changed. It was specified. Therefore, when measuring the sugar content and the maturity at the same time, it is necessary to irradiate light of different wavelengths in several times and sequentially receive the light, which takes time. In particular, measuring a large number of reflected light or diffused light with different wavelengths significantly increases the number of light sources and the number of times of measurement, leading to an increase in the size of the apparatus and an increase in measurement time.

  Therefore, although it is possible to measure the light of a specific wavelength by spectroscopically dividing the reflected light or diffused light without specifying the wavelength of the irradiation light, the price of the entire measuring apparatus is high because the spectroscope is expensive. It was supposed to soar.

  Furthermore, when calculating the characteristics of the fruits and vegetables based on the amount of light transmitted into the fruits and vegetables, an error may occur due to external light entering the irradiated light and the received light. For this reason, it is considered to place the light receiving part at the center and seal between the surrounding light emitting part and the fruit and vegetable surface, but external light enters during transmission from the light receiving part to the optical sensor or at the transmission end. In some cases, an error would occur.

  Therefore, the present invention has been made in view of the above-mentioned points, and its purpose is to improve the accuracy of measured values of the characteristics of fruits and vegetables by suppressing the influence of external light on the received light, and a plurality of ranges. It is an object to provide a non-destructive measuring apparatus for fruits and vegetables capable of simultaneously measuring light of the wavelengths.

  In order to achieve the above object, the present invention provides a light emitting unit that irradiates light to a measuring object fruit, a light receiving unit that receives diffused light emitted from the fruit, and a transmitted light amount by diffused light detected by the light receiving unit. In a non-destructive measuring apparatus for fruits and vegetables comprising processing means for calculating and calculating an evaluation amount of fruits and vegetables from a calibration curve, a plurality of light sensors disposed on a substrate and individually disposed in the vicinity of each light sensor A plurality of optical filters, a filter holding unit that holds the optical filter while individually surrounding the optical sensor, and a plurality of optical fibers, and diffused light detected by the light receiving unit is supplied to each optical filter. A plurality of optical transmission cables for transmission, and a cable support section that surrounds each end of the optical transmission cable and holds the end in the vicinity of each optical filter.

  According to the above configuration, the diffused light incident from the light receiving unit is transmitted to the plurality of optical filters via the optical transmission cable, and only light having a predetermined range of wavelengths reaches the plurality of optical sensors via the optical filter. Therefore, many types of light can be detected at the same time. Therefore, it is possible to calculate the amount of transmitted light necessary for determining a desired characteristic for a specific fruit and vegetable depending on which optical filter measurement value is selected. The diffused light means the light emitted from the fruits and vegetables after the light irradiated to the fruits and vegetables is diffused inside the fruits and vegetables. It is.

  According to the present invention, the optical filter can irradiate the optical sensor with light having a wavelength in a specific range of diffused light, and the diffused light can be classified at low cost. In addition, the end of the optical transmission cable is surrounded by a cable support part, the periphery of the optical sensor is surrounded by a filter holding part, and the optical filter is held inside the filter holding part, so that the connection position of the light transmission path Therefore, the influence of external light on the transmitted diffused light can be suppressed.

  Furthermore, since multiple light sensors can be irradiated with light of different ranges of wavelengths simultaneously, various measurement values can be obtained simultaneously for the fruits and vegetables to be measured, based on the light of the wavelengths to be measured, Evaluation quantities of other types of characteristics can be calculated simultaneously. In addition, since the diffused light of the plurality of wavelengths is obtained by classifying one diffused light, it can be measured in a short time.

It is explanatory drawing which shows embodiment of this invention. It is II-II sectional drawing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the internal structure of this embodiment. As shown in this figure, the outline of this embodiment will be described. A light emitting unit 1 and a light receiving unit 2 are provided in the vicinity of an opening of a bottomed cylindrical measuring device A, and diffused light detected by the light receiving unit 2 is as follows. The optical transmission cable group 3 and the individual optical transmission cables 31 branched from the optical transmission cable group 3 are transmitted to the cable support 4 provided near the bottom of the apparatus main body A. . The cable support portion 4 supports the end of the branched optical transmission cable 31 and is continuous with the filter holding portion 5 that holds the optical filter. The filter holding unit 5 is provided in the vicinity of the substrate 6 having an optical sensor.

  The light emitting unit 1 includes a frame body 10 formed in a bottomed cylindrical shape with a wall surface portion and a bottom surface portion, and light emitters 11 and 12 are provided on the bottom portion. The light emitters 11 and 12 are provided at the bottom of the frame body 10, and the frame body 10 reflects the light of the light emitters 11 and 12 to guide the light toward the opening of the frame body 10. Yes. That is, the side wall of the frame 10 is inclined so as to expand from the bottom surface side toward the opening side. Note that the bottom and side portions of the frame 10 are coated with a reflective agent so that light can be reflected. Further, an annular buffer member is provided in the opening of the apparatus main body A that supports the frame body 10 so that the fruits and vegetables F are not damaged when the light emitting unit 1 is brought into contact with the surface of the fruits and vegetables F. It is configured.

  In the present embodiment, the above-described light emitters 11 and 12 use halogen lamps capable of simultaneously emitting near-infrared light from visible light, and a plurality (two in the figure) are arranged around the light receiving unit 2. Yes. Since the light receiving unit 2 is provided at the center of the light emitting unit 1, the light receiving unit 2 is arranged concentrically around the light receiving unit 2.

  The light emitters 11 and 12 are not limited to halogen lamps, and can be used as the light emitters of the present embodiment as long as they can irradiate light with a wide range of wavelengths at the same time. Further, the number of the light emitters 11 and 12 is not limited to two, and three or more even if there is only one, as long as it can transmit fruits and vegetables and obtain diffused light. It may be.

  The light receiving unit 2 is configured by a cylindrical body that penetrates the bottom surface of the frame 10 of the light emitting unit 1, and a bowl-shaped bracket is formed on the cylindrical body so that the bracket abuts on the bottom of the frame 10. Is provided. The tip of the cylinder is open, and diffused light can enter from the tip. Accordingly, by irradiating light from the light emitting unit 1 with the fruit F to be measured being brought into contact with the light receiving unit 2, the light from the light emitting unit 1 is irradiated on the fruit F and transmitted through or diffusely diffused. Light can be incident from the light receiving unit 2. At the tip of the cylinder body, a buffer member 21 having a shape of a circular ring (parabolic shape) gradually widened is mounted, so that the impact with the surface of the fruits and vegetables F can be reduced when contacting the fruits and vegetables F. Yes. The buffer member 21 is in contact with the surface of the fruits and vegetables, and since an elastic material is used, the buffer member 21 can be in close contact with the surface of the fruits and vegetables. It is configured to suppress intrusion.

  The optical transmission cable group 3 in which the optical transmission cables 31 are concentrated is inserted into the light receiving unit 2 having such a configuration, and the tip of the optical transmission cable group 3 is in the vicinity of the opening of the cylindrical body constituting the light receiving unit 2 Is located. Accordingly, the diffused light incident on the inside of the cylindrical body of the light receiving unit 2 is incident on the tip of the optical transmission cable group 3 at the same time.

  The optical transmission cable group 3 branches into individual optical transmission cables 31 in the middle from the light receiving unit 2 to the cable support unit 4. Each optical transmission cable 31 is configured by a collection of extremely thin optical fibers. In the present embodiment, about 1000 optical fibers are used for one optical transmission cable 31, thereby improving randomness. That is, when the diffused light is transmitted by one or an extremely small number of optical fibers, the amount of light is determined by the light incident on the small number of optical fibers. When the optical transmission cable 31 is configured, the amount of light for each wavelength can be measured by the total amount of light incident on each optical fiber, thereby suppressing the occurrence of measurement errors for the amount of light of a specific wavelength to be measured. Can do.

  The optical transmission cable group 3 or the optical transmission cable 31 is formed with one loop as a whole in the middle of the light receiving unit 2 and the cable support unit 4. The position of this loop formation is such that the optical fiber constituting the optical transmission cable 31 forms a loop regardless of before and after branching. When the optical fiber forms a loop, the optical fiber is bent. Therefore, when a slight amount of external light is applied to the cladding, the optical fiber is prevented from reaching the core. Thus, the diffused light detected by the light receiving unit 2 is transmitted to the cable support unit 4 while suppressing the influence of external light by the optical transmission cable group 3 and the individual optical transmission cables 31.

  Next, the peripheral structure of the end of the optical transmission cable group 3 and the substrate 6 will be described. FIG. 2 is a diagram illustrating details of a range from the end of the optical transmission cable group 3 to the substrate 6. As shown in this figure, the individual optical transmission cables 31, 32,... Branched from the optical transmission cable group 3 are covered with covering materials 31a, 32a,. The entire vicinity of the end portion including the covering materials 31 a, 32 a,... Is supported inside the cable support portion 4.

  The cable support portion 4 is made of a resin having a high light blocking rate, and the through holes 41, 42,... Through which the optical transmission cables 31, 32,. , 42,... Are provided with screw holes through which the fixing screws 43, 44,. .. Are inserted into the through holes 41, 42,... Together with the covering materials 31a, 32a,... And the fixing screws 43, 44,. The ends of the optical transmission cables 31, 32,... Are supported in the through hole of the cable support unit 4 and are irradiated with diffused light transmitted in the through hole. Will be able to.

  When the optical transmission cables 31, 32,... Are supported in the through holes of the cable support portion 4, the ends of the optical transmission cables 31, 32,. It is fixed at a position very close to the surface (opposing surface). The ends of the optical transmission cables 31, 32,... Do not have to coincide with the contact surfaces, but are supported close to each other so as not to differ greatly. This is to allow light to reach optical filters 51, 52,... And optical sensors 61, 62,. Further, the covering materials 31a, 32a,... Are provided in a range sufficiently longer than the range inserted into the through hole, and the tips of the fixing screws 43, 44,. , ... come into contact. In this way, the fixing screws 43, 44,... Always come into contact with the covering material, so that the fixing screws 43, 44,... Do not contact the optical transmission cables 31, 32,. Therefore, the optical transmission cables 31 and 32 can be protected.

  Further, in the surface (opposing surface) of the cable support 4 on the side facing the filter holding part 5, the filter holding part 5 has a region where the tips of the optical transmission cables 31, 32,. A protruding portion that protrudes toward is formed. In order to form the protruding portion, a recess is provided around the area. Furthermore, you may form the part which protrudes further from the said protrusion part around the recessed part. As described above, by providing irregularities on the contact surface, when the cable support 4 and the filter holding unit 5 are connected to each other, even if a slight gap may be generated between them, the irregularities cause external light. Can prevent the intrusion. Further, the presence of the irregularities allows the filter holder 5 to be fitted to the surface as will be described later.

  It is expected that the surfaces of the covering materials 31a, 32a, ... of the optical transmission cables 31, 32, ... will be slightly deformed by tightening the fixing screws 43, 44, ... In order to prevent external light from entering through the gap caused by the deformation, in the vicinity of the openings of the through holes 41, 42,... For example, Moltoprene (registered trademark, etc.) MP1, MP2,.

  The filter holding part 5 is continuously arranged on the cable support part 4 having the above configuration. The filter holding part 5 is made of a resin having a high light shielding rate, like the cable support part 4. As shown in the drawing, on the contact surface side between the cable support portion 4 and the filter holding portion 5, an uneven portion for integrally connecting the both is formed. Further, the filter holding part 5 is provided with a through hole of an appropriate size, and the optical filters 51, 52,... Can be arranged in the through hole.

  Further, a concave portion into which the protruding portion formed on the cable support portion 4 can be fitted is formed on the surface (opposing surface) of the filter holding portion 5 on the side facing the cable support portion 4, and the optical filter is held by this concave portion. An area to be provided is provided. That is, the through hole is formed in the center of the recess, and the optical filters 51, 52,... Are held in the through hole. In addition, in order to form such a recessed part, the protrusion part is formed in the periphery of the filter holding | maintenance area | region, and this protrusion part is comprised so that it may fit in the recessed part of the said cable support part 4. FIG. Further, a concave portion formed deeper than the concave portion may be provided around the protruding portion. In this case, the concave portion may be brought into contact with the most protruding portion of the cable support portion 4. It becomes possible.

  Therefore, the end of the optical transmission cable 31, 32,... And the optical filter 51, 52,. The diffused light is irradiated from the end portions of the optical transmission cables 31, 32,... Toward the optical filters 51, 52,. Moreover, the said uneven | corrugated | grooved part is for hold | maintaining the through-holes 41,42, ... for inserting the terminal of the optical transmission cables 31,32, ..., and the optical filters 51,52, ... It is provided so as to surround the through hole while having an appropriate distance from the through hole. As a result, the light entering from the gap between the contact surfaces of the cable support portion 4 and the filter holding portion 5 is blocked by the uneven portion, so that the light does not reach the through hole. In place of the configuration that blocks the external light by the concave and convex portions, a light shielding resin material (for example, maltoprene (registered trademark)) MP3 is provided around the contact surface between the cable support portion 4 and the filter holding portion 5. It is good also as a structure which sticks MP4. Furthermore, in addition to the structure having the concavo-convex part, the light shielding resin materials MP3 and MP4 may be attached.

  Here, as the optical filters 51, 52,..., Necessary numbers (for example, 14) are arranged, and each of them can transmit light of different wavelengths. Therefore, for example, if 14 optical filters are used, light of 14 types of wavelengths can be obtained. In the case where it is assumed that light having a wavelength of about 1000 nm is measured from light having a wavelength of about 700 nm, Fourteen types of light with desired wavelengths can be obtained. Thereby, it is possible to obtain the same effect as in the case of performing spectroscopy using a spectroscope. The 14 types described above are examples, and this number can be increased or decreased. Even when 14 types of light with different wavelengths are detected, when calculating the characteristics of fruits and vegetables, only the measured values of several types of light that should be required can be selected and used. Further, the light that can be transmitted by the optical filters 51, 52,... May have a predetermined wavelength width from the center wavelength, but the light having the desired wavelength means the center wavelength. The optical filter of this embodiment transmits light having a wavelength in the range of about 5 nm before and after the center wavelength, but the wavelength width before and after the center wavelength is not limited to this.

  As described above, the filter holding unit 5 has a plurality of (for example, 14) through holes for holding a plurality of (for example, 14) optical filters 51, 52,. In FIG. 2, two optical filters 51 and 52 are held in two through-holes, but a similar configuration is continued in, for example, seven rows in the direction perpendicular to the paper surface of FIG. An optical filter can be arranged. In order to simultaneously irradiate the individual optical filters 51, 52,... With diffused light, the optical transmission cables 31, 32,... Have the same number as the optical filters 51, 52,. These ends are supported by the cable support 4 by the same number (for example, 14) of through holes 41, 42,.

  The through hole provided in the filter holding part 5 is provided with an opening facing the optical sensors 61, 62,... In addition to the opening connected to the optical transmission cables 31, 32,. This opening part arrange | positions the optical sensors 61, 62, ... which protrude from the board | substrate 6 in a through-hole, and the periphery of the said opening part is optical sensor 61, by opening by a predetermined magnitude | size. 62,... Can be surrounded. .. Are arranged with respect to the respective through holes, so that the optical sensors 61, 62,... Face the optical filters 51, 52,. It is arranged like this.

  Here, as the optical sensors 61, 62,..., For example, a CMOS sensor manufactured on a semiconductor substrate can be used, or a plurality of photo-resistors or the like may be mounted on the substrate. In any case, since the optical sensors 61, 62,... Protrude from the surface of the substrate 6, the periphery of the optical sensors 61, 62,. By encircling, it is possible to prevent external light from entering from the surface of the substrate 6. In addition, the substrate 6 can be colored black, for example, so that light transmitted through the substrate can be absorbed, and the light shielding rate can be further improved.

  Further, in the present embodiment, light shielding members 71, 72,... Are interposed between the filter holding unit 5 and the optical sensors 61, 62,. This is because a small amount of external light entering from between the filter holding unit 5 and the optical sensors 61, 62,... Reaches the photosensitive surface of the optical sensors 61, 62,. It is restraining to do. The light shielding members 71, 72,... Are formed into a film shape with a material having a high light shielding rate, and the center of the light shielding members 71, 72,. The diffused light transmitted through the optical filters 51, 52,... Can be irradiated to the center of the photosensitive surface.

  Since this embodiment is configured as described above, light is transmitted to or diffusely reflected in the fruits and vegetables by irradiating the fruits and vegetables F with the light emitters 11 and 12, and then the light receiving unit 2 Diffused light is detected, and the diffused light detected by the light receiving unit 2 passes through the individual optical transmission cables 31, 32,... Branched from the optical transmission cable group 3, and the optical filters 51, 52,. Will be transmitted. The light having a specific wavelength transmitted through the optical filters 51, 52, ... reaches the optical sensors 61, 62, ..., and the amount of light is measured by the optical sensors 61, 62, .... Therefore, the diffused light passing through the plurality of optical transmission cables 31, 32,... Can be classified for each wavelength, and light of different wavelengths can be measured simultaneously. The light quantity values measured by the optical sensors 61, 62,... Are calculated by processing means (not shown), and the characteristics (evaluation amount) of the measurement target fruits and vegetables F are calculated. .

  In calculating the evaluation amount, a calibration curve based on the correlation between the actual measurement value and the measurement value (absorbance measurement value) is used in advance, and the calibration curve data created in advance is stored in the memory of the processing means. ing. Since the calibration curve to be used varies depending on the type of fruits and vegetables to be measured, various calibration curves are classified and stored. A calibration curve to be applied is selected and used by specifying the type and harvest time of the fruits and vegetables to be measured at the time of measurement. Also, select the type of light (wavelength range) to be calculated according to the characteristics to be measured (sugar content, ripeness, hardness, etc.) (specifically, multiply the light amount of each range of wavelengths by a coefficient) In other words, calculation processing is performed for a desired characteristic.

  Although this embodiment is as above, this invention is not limited to the said embodiment, A various aspect can be taken. For example, as described above, an annular buffer member is attached to the tip of the opening of the light emitting unit 1, and this buffer member is configured to appropriately shield light outside the device A. However, if the light intensity of the light emitters 11 and 12 is large, the diffused light can be measured with appropriate accuracy even when the light is not sufficiently shielded. Therefore, although the said buffer member can be provided with the material with light-shielding property, it is not limited to it.

  Moreover, although the fact that a plurality of halogen lamps were used as the light source has been described, in this embodiment, the amount of light is adjusted so that the total of the plurality of halogen lamps is about 20 W. Accordingly, for two halogen lamps, one having 10 W is used. When three halogen lamps are used, one having 6 to 7 W is used. Thus, when a 20 W halogen lamp is used, desired diffused light can be detected by irradiation for about 0.25 seconds, and the calculation result is output immediately after detection of this diffused light. The time required from the start to the result output can be set to an extremely short time of about 0.5 seconds.

DESCRIPTION OF SYMBOLS 1 Light emission part 2 Light reception part 3 Optical transmission cable group 4 Cable support part 5 Filter holding part 6 Board | substrate 11,12 Light-emitting body (halogen lamp)
21 Buffer member 31, 32 Optical transmission cable 31a, 32a Cover material 51, 52 Optical filter 61, 62 Optical sensor 71, 72 Light shielding member

Claims (6)

A light emitting unit for irradiating light to the measuring object fruit, a light receiving unit for receiving diffused light emitted outside the fruit after the light emitted from the light emitting unit diffuses inside the fruit, and a light receiving unit In the non-destructive measuring apparatus for fruits and vegetables, comprising processing means for calculating the amount of transmitted light by the diffused light and calculating the evaluation amount of the fruits and vegetables from the calibration curve,
A plurality of optical sensors disposed on the substrate;
A plurality of optical filters arranged individually in the vicinity of each optical sensor and having different transmission wavelengths;
A filter holding unit for holding the optical filter while individually surrounding the optical sensor;
A plurality of optical transmission cables configured by a plurality of optical fibers and transmitting diffused light detected by the light receiving unit to the optical filters;
A cable support portion that is connected to the filter holding portion while surrounding each end of the optical transmission cable, and holds each end of the optical transmission cable in the vicinity of the optical filter. Nondestructive measuring device. The non-destructive measuring apparatus for fruits and vegetables according to claim 1, further comprising a light shielding member interposed between the filter holding part and the optical sensor and opening near the center of the photosensitive surface of the optical sensor. . The filter holding part is a filter holding part formed by forming a recess in a region where the optical filter is held on the surface facing the cable supporting part, and the cable supporting part faces the filter holding part. A cable supporting part formed by forming a protruding part in a region where each end of the transmission cable is held among the surfaces to be engaged, and by fitting the protruding part of the cable supporting part into the concave part of the filter holding part The non-destructive measuring apparatus for fruits and vegetables according to claim 1 or 2, wherein the cable support part is connected to a filter holding part. The non-destructive measuring apparatus for fruits and vegetables according to any one of claims 1 to 3, wherein the plurality of optical filters are a plurality of optical filters that pass wavelengths in different ranges. The plurality of optical transmission cables form an optical transmission cable group assembled in the vicinity of the light receiving unit, and a tip of the optical transmission cable group is disposed in the light receiving unit. A non-destructive measuring apparatus for fruits and vegetables according to crab. The non-destructive measuring apparatus for fruits and vegetables according to any one of claims 1 to 5, wherein the optical transmission cable is formed with at least one loop in the middle of the light receiving section and the transmission support section.

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