JP2006047209A - Spectroscopic analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectroscopic analyzer capable of precisely measuring the quality evaluation value of a measuring target by properly controlling the temperature of a light receiving means in a non-disadvantageous state bringing about the scaling-up of the spectroscopic analyzer or an increase in cost. <P>SOLUTION: The spectroscopic analyzer is equipped with temperature detecting means 63a and 63 for detecting the temperature of the light receiving means 2 for receiving the spectrally diffracted light obtained by spectrally diffracting the transmitted light from the measuring target, temperature adjusting means 60a and 60b for adjusting the temperature of the light receiving means 2 and a temperature control means for controlling the operation of the temperature adjusting means 60a and 60b so as to hold the temperature of the light receiving means 2 to a target temperature. The temperature control means is constituted so as to be freely changed over to a high temperature side adjusting state controlling the operation of the temperature adjusting means 60a and 60b by setting a high temperature side target temperature and a low temperature side adjusting state controlling the operation of the temperature adjusting means 60a and 60b by setting a low temperature side target temperature lower than the high temperature side target temperature. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is based on light projecting means for projecting light onto an object to be measured, light receiving means for dispersing transmitted light or reflected light from the object to be measured and receiving the dispersed light, and a measurement result of the light receiving means. The present invention also relates to a spectroscopic analysis apparatus configured to include an evaluation unit that obtains a quality evaluation value of a measurement object.

  The spectroscopic analyzer having the above-described configuration is a characteristic of transmitted light and reflected light obtained from a measurement object by irradiating the measurement object with light by a light projecting unit, for example, fruit and vegetables such as mandarin orange and apple. In order to obtain a quality evaluation value of an object to be measured, for example, a quality evaluation value such as sugar content or acidity, in a non-destructive state, in a spectroscopic analyzer having such a configuration, conventionally, There was something configured.

  That is, as a light projecting unit as a light projecting unit that includes a light source lamp such as a halogen lamp and projects light onto the object to be measured, and a light receiving unit that splits the transmitted light from the object to be measured and receives the dispersed light. And a light receiving unit for the spectral detection that can measure the amount of light per wavelength separated by the diffraction grating that separates the transmitted light from the object to be measured and the diffraction grating. In addition, there is a configuration that includes a cooling Peltier element for the light receiving sensor to prevent a temperature change of the light receiving sensor (see, for example, Patent Document 1). .

JP-A-8-233732

  In the above conventional configuration, when the temperature of the light receiving sensor for spectral detection provided in the light receiving means changes, the light quantity measurement value that is the output value when the light is measured may fluctuate even if the same quantity of light is received. There is a possibility of causing a measurement error due to that, and therefore, the temperature variation of the light receiving sensor is prevented as described above.

  However, in the above conventional configuration, when the outside air temperature is high, it is possible to prevent the temperature of the light receiving sensor from rising by cooling with the Peltier element, but in winter when the outside air temperature is low, Even if the temperature of the light receiving means becomes low due to the influence of the outside air temperature, the temperature cannot be adjusted at that time, so the temperature change of the light receiving means cannot be suppressed to a small one, and the light receiving state must be maintained in an appropriate state. There was a disadvantage that could not be.

  Therefore, in order to maintain the temperature of the light receiving means at a constant temperature regardless of whether the outside air temperature is high as in summer or the outside temperature is low as in winter, the light receiving means As a configuration in which the temperature adjusting means that can perform not only the cooling action but also the heating action is provided, it is conceivable that the temperature adjustment means is used to adjust the temperature of the light receiving means so as to be always a constant temperature.

  However, in the configuration in which the temperature is adjusted so as to be always a constant temperature in this way, if the target temperature is set to a higher temperature, for example, close to the outside temperature in summer, the outside temperature and the target temperature in summer However, in winter when the outside air temperature is low, the difference between the outside air temperature and the target temperature is large and a large air conditioning capacity is required. There is a disadvantage that a large-scale temperature adjusting means having the capability is required, resulting in high cost. In addition, if the target temperature is set to a low temperature close to the outdoor temperature in winter, for example, in summer when the outdoor temperature becomes high, the difference between the outdoor temperature and the target temperature becomes large and large. Since air conditioning capability is required, a large temperature adjustment means having a large air conditioning capability is also required in this case. Therefore, in the configuration in which the temperature is adjusted so that the temperature is always constant, a large temperature adjusting means having a large air conditioning capability is required, and there are disadvantages such as an increase in the size of the apparatus and an increase in cost.

  In the above conventional configuration, only the light receiving sensor is cooled by the cooling Peltier element. Therefore, in another device other than the light receiving sensor in the light receiving means, for example, an optical system member such as a diffraction grating. It has not been able to cope with the disadvantage that measurement errors occur due to changes in the light receiving state due to temperature changes.

  In addition to the description of the fact that the above-described optical system member causes a measurement error due to a change in the light receiving state, in the above-described conventional configuration, the transmitted light from the object to be measured is dispersed by a diffraction grating and the light receiving is performed. Since the light quantity for each wavelength spectrally separated by the sensor is measured, the light receiving sensor is configured to include a plurality of unit light receiving units in order to measure the light quantity for each spectral wavelength. For example, when the temperature of the diffraction grating, which is an optical system member, fluctuates, distortion is caused by a difference in expansion coefficient with respect to a temperature change between the light receiving portion that receives light in the diffraction grating and the base portion that supports the light receiving portion. As a result, the unit light receiving unit that receives the same wavelength in the light receiving sensor may change. As a result, the light quantity measurement value for each wavelength cannot be accurately measured, and a measurement error may occur in the quality evaluation value of the measurement object.

  It is an object of the present invention to accurately measure the quality evaluation value of an object to be measured by appropriately managing the temperature of the light receiving means in a state where there is no disadvantage such as an increase in the size of the apparatus or an increase in cost. Therefore, it is possible to provide a spectroscopic analysis apparatus that can perform the above-described process.

  A first characteristic configuration of the present invention includes a light projecting unit that projects light onto a measurement object, a light receiving unit that splits transmitted light or reflected light from the measurement object and receives the split light, and the light receiving unit. A spectroscopic analyzer configured to include an evaluation unit that obtains a quality evaluation value of an object to be measured based on a measurement result of the temperature detection unit that detects a temperature of the light receiving unit; and Temperature adjusting means for controlling the operation of the temperature adjusting means so that the temperature of the light receiving means detected by the temperature detecting means is maintained at a target temperature, and the temperature control means However, on the basis of the switching command of the switching command means, a high temperature side adjustment state in which the high temperature side target temperature is set to control the operation of the temperature adjustment means, and a low temperature side target temperature lower than the high temperature side target temperature. Of the temperature adjusting means In that it is configured to be freely switched between the low-temperature side adjustment state for controlling the movement.

  According to the first characteristic configuration, when the temperature control means is switched to the high temperature side adjustment state based on the switching command of the switching command means, the light receiving means that sets the high temperature side target temperature and is detected by the temperature detection means. The operation of the temperature adjusting means is controlled so that the temperature of the temperature is maintained at the target temperature on the high temperature side. Further, when the low temperature side adjustment state is switched based on the switching command of the switching command means, a low temperature side target temperature lower than the high temperature side target temperature is set, and the temperature of the light receiving means detected by the temperature detection means Controls the operation of the temperature adjusting means so as to maintain the target temperature on the low temperature side.

  For example, when the outside air temperature is high such as in summer, the target temperature on the high temperature side is set by switching to the high temperature adjustment state, so the temperature difference between the outside air temperature and the target temperature on the high temperature side is small, Since the operation of the temperature adjusting means is controlled so that the temperature of the light receiving means is maintained at the target temperature on the high temperature side with such a small temperature difference, the air conditioning capacity of the temperature adjusting means should be small. Can do. Also, when the outside air temperature is low such as in winter, the target temperature on the low temperature side is set by switching to the low temperature side adjustment state, so the temperature difference between the outside air temperature and the target temperature on the low temperature side is small, Since the operation of the temperature adjusting means is controlled so that the temperature of the light receiving means is maintained at the target temperature on the low temperature side with such a small temperature difference, the air conditioning capacity of the temperature adjusting means should be small. Can do.

  Therefore, even if the outside air temperature is high such as in summer and the case where the outside air temperature is low such as in winter, a small air conditioning capacity can be used, so use a small temperature adjustment means. Is possible.

  As described above, although the target temperature varies between the target temperature on the high temperature side and the target temperature on the low temperature side, the temperature of the light receiving means is maintained at the target temperature on the high temperature side when switched to the high temperature side adjustment state. Thus, it is possible to suppress the temperature change of the light receiving means to be small, and in the state switched to the low temperature side adjustment state, the temperature of the light receiving means becomes the target temperature on the low temperature side. Since the operation of the temperature adjusting means is controlled so as to be maintained, it is possible to suppress the temperature change of the light receiving means to be small.

  As a result, even in cases where the outside air temperature is high, such as in summer, and in the case where the outside air temperature is low, such as in winter, the temperature change of the light receiving means is suppressed by suppressing it to a low one. The resulting measurement error can be reduced. The light receiving means includes an optical system member such as a diffraction grating for separating transmitted light or reflected light from the object to be measured, and a light receiving sensor for spectral detection for measuring the amount of light for each dispersed wavelength. However, as described above, by suppressing the temperature change of the light receiving means to be small, the temperature change of the light receiving sensor is suppressed, and the output value when the light is measured even if the same amount of light is received Therefore, it is possible to easily avoid the disadvantage that a measurement error occurs due to the fluctuation of the light quantity measurement value. In addition, it is possible to reduce the occurrence of distortion of the optical system member due to temperature change, and to easily avoid the disadvantage that a measurement error occurs due to such distortion of the optical system member.

  Incidentally, as described above, when switching between the high temperature side adjustment state and the low temperature side adjustment state, after switching to either state, the target temperature is controlled according to that state. Since the target temperature differs between the side adjustment state and the low temperature side adjustment state, the temperature of the light receiving means changes. However, for such a change in temperature for a long-term range, a measurement error does not occur because the following processing is generally performed as appropriate.

  That is, for example, the amount of light having a predetermined light attenuation instead of the object to be measured can be measured when the light amount measurement value fluctuates even when the same amount of light is received due to the temperature change of the light receiving means. Obtain the measured light quantity by receiving the transmitted or reflected light using the calibration reference body, determine the value as the reference value, and obtain the transmitted or reflected light from the measurement object By executing the process of normalizing the measured light quantity value with the reference value, it is possible to eliminate fluctuations in the measured light quantity value. In addition, when the temperature change causes the optical system member to be distorted and the unit light-receiving unit that receives the same wavelength of the dispersed light changes with the temperature change, for example, it is reduced to a plurality of specific wavelengths. By executing the wavelength calibration process of the light receiving means using the wavelength calibration body having the peak of the light rate, it is possible to prevent the unit light receiving unit that receives the same wavelength from changing.

  Therefore, a small one with a small air-conditioning capability can be used as the temperature adjusting means, and by appropriately managing the temperature of the light receiving means with no disadvantage such as an increase in the size of the apparatus or high cost, It has become possible to provide a spectroscopic analyzer that can accurately measure the quality evaluation value of an object to be measured.

  According to a second characteristic configuration of the present invention, in addition to the first characteristic configuration, a casing is provided to surround the light receiving means in a state where an air layer is formed on an outer peripheral portion of the light receiving means, and the temperature adjusting means is provided in the air layer. It is in the point comprised so that it may adjust temperature with respect to it.

  According to the second characteristic configuration, the temperature adjustment means acts on the air layer formed on the outer peripheral portion of the light receiving means inside the casing. That is, since the temperature is controlled with respect to the air layer covering the entire light receiving means, the temperature of the entire light receiving means can be uniformly adjusted without any bias.

  In other words, when the temperature adjusting means performs a temperature adjustment operation on the light receiving means, the temperature adjusting action is performed only on a local portion of the light receiving means if the temperature adjusting action is in contact with the light receiving means. As a result, the temperature adjusting action is not received in other parts of the light receiving means, and there is a possibility that proper temperature adjustment cannot be performed as a whole of the light receiving means. On the other hand, according to the above configuration, since the temperature adjusting means regulates the temperature of the air layer in the casing, the light receiving means is changed by changing the temperature of the air layer formed on the outer periphery of the light receiving means. The entire temperature can be adjusted evenly.

  According to a third characteristic configuration of the present invention, in addition to the second characteristic configuration, a pair of the temperature adjusting means is provided in a state where the temperature adjusting means is distributed and positioned on both lateral sides of the light receiving means, and the temperature control means is provided with the pair of temperature. The adjustment means is configured to be controlled.

  According to the third characteristic configuration, the temperature adjusting action is performed on the air layer in the casing by the pair of temperature adjusting means that are distributed and positioned on both lateral sides of the light receiving means. By performing the temperature control action from both lateral portions, it is possible to perform the temperature control function uniformly with less bias over the entire light receiving means.

  According to a fourth feature configuration of the present invention, in addition to any of the first feature configuration to the third feature configuration, the measurement object is a fruit vegetable.

  According to the fourth feature configuration, when the object to be measured is a fruit vegetable, the same kind of object to be measured is not always evaluated throughout the year, and the type of the target fruit vegetable changes according to the season. Conceivable. Therefore, in summer, by switching to the high temperature side adjustment state and controlling the operation of the temperature adjustment means, the kind of fruit and vegetables harvested in the summer is evaluated in a state where the temperature difference between the outside temperature and the target temperature is small. It becomes possible to perform processing appropriately. Also, in winter, by switching to the low temperature side adjustment state and controlling the operation of the temperature adjustment means, the kind of fruits and vegetables harvested in the winter is evaluated in a state where the temperature difference between the outside air temperature and the target temperature is small. It becomes possible to perform processing appropriately.

Hereinafter, a case where an embodiment of a spectroscopic analysis apparatus according to the present invention is applied to an internal quality evaluation apparatus for fruit vegetables will be described with reference to the drawings.
The internal quality evaluation device is a device for measuring a mandarin orange, which is an example of a fruit vegetable, as an object to be measured, and is a device for measuring sugar content and acidity as an internal quality of such fruit vegetable, and is to be measured located at a measurement location. Light is projected onto the object, the transmitted light from the object to be measured is dispersed, the dispersed light is received and the spectrum data is measured, and the object is measured based on the spectrum data and the calibration formula for quality analysis. The quality evaluation value of the measurement object is obtained.

  More specifically, as shown in FIGS. 1 and 2, the light projecting unit 1 as a light projecting unit that projects light onto the object to be measured, and the transmitted light or reflected light from the object to be measured are spectrally separated. A light receiving unit 2 serving as a light receiving unit that receives light, a control unit 3 using a microcomputer that executes various control processes, and the like are configured. The objects to be measured M are arranged in a row by a transport conveyor 4 serving as a transport unit. It is configured to be placed and conveyed in a tandem shape, and is configured to sequentially pass through measurement points P by this apparatus. Then, the light projecting unit 1 and the light receiving unit 2 are arranged with respect to the measurement object M located at the measurement location P, distributed to the left and right side portions of the measurement location P, that is, the both sides in the transport width direction of the transport conveyor 4. It is the composition which becomes.

A configuration of the light projecting unit 1 will be described.
As shown in FIGS. 4 and 6, the light projecting unit 1 includes two light sources 5, and an object to be measured that is positioned at a measurement location P on the optical axes for irradiating light from the light sources 5 different from each other. It is comprised so that M may be irradiated. Incidentally, each light source 5 is constituted by a halogen lamp. Further, the two optical axes for irradiation by the respective light sources 5 are configured to intersect at or near the surface portion of the measurement object M located at the measurement location P. That is, two light sources 5 are provided in a state of being separated along the transport direction by the transport conveyor 4, and the following optical system is provided corresponding to each of the two light sources 5. A concave light reflecting plate 6 is provided for reflecting the light emitted from the light source 5 to focus on the surface of the object M to be measured, and near the focal position of the light condensed by the light reflecting plate 6. Light that has passed through the large aperture hole 7a and the aperture plate 7 that suppresses the spread of the light after being condensed by passing through the large aperture hole 7a in the radial direction. Irradiating state adjusting plate 8 which can be switched to a state where light is allowed to pass through, a state where light is allowed to pass through a small aperture 8a, and a state where light is blocked, and light from condensed light source 5 is converted into parallel light. Each of the collimator lens 9 to be changed, the reflecting plate 10 that reflects the light changed to parallel light and bends it toward the measurement location, and the condensing lens 11 that collects the light reflected by the reflecting plate 10 is 1. Provided as an optical system for each light source 5 To have. Each adjusting plate 8 is integrally pivoted by an irradiation range adjusting electric motor 12 and can be switched to each state. And this light projection part 1 becomes a structure by which each above-mentioned member was built in the casing 13, and was assembled in the unit form.

Next, the configuration of the light receiving unit 2 will be described.
As shown in FIG. 4, the light receiving unit 2 includes a condenser lens 14 that condenses the light transmitted through the measurement object M into parallel light, and a half that reflects upward a part of the light changed to parallel light. The mirror 15, a condensing lens 16 that condenses the measurement target light reflected upward, and an open state that allows the light that has passed through the condensing lens 16 to pass as it is and a shielding state that prevents passage of the light can be switched. When light that has passed through the open light receiving shutter mechanism 17 and the open light receiving shutter mechanism 17 is incident, the light receiving shutter mechanism 17 is provided with a spectroscope 18, a spectroscope controller 23A, and the like. Configured. A filter switching mechanism 19 that switches a plurality of various filters for adjusting the amount of light that acts on the light incident on the spectroscope 18 is provided below the light receiving shutter mechanism 17, that is, on the upper side in the light incident direction. Is provided. And the light-receiving part 2 becomes the structure assembled | attached in the state enclosed by the casing 2A with each member as above mentioned in the shape of a unit. Therefore, the casing 2 </ b> A that surrounds the light receiving part 2 in a state where the air layer Q is formed on the outer peripheral part of the light receiving part 2 is provided.

  As shown in FIG. 9, the spectroscope 18 includes a concave mirror 21 a that reflects the measurement target light incident from the light entrance 20 in a focused state, and a spectroscopic unit that splits the reflected light into light of a plurality of wavelengths. As a diffraction grating 22, a concave mirror 21 b that reflects light collected by the diffraction grating 22 in a focused state, and receives the reflected light, and detects the amount of light for each wavelength to measure spectral spectrum data. The region through which light passes is arranged in a dark box 24 made of a light-shielding material that blocks light from the outside. The light receiving sensor 23 simultaneously receives light in a specific wavelength region (for example, a range of about 600 nm to 1000 nm) out of the light that is split by the diffraction grating 22 and reflected by the reflecting mirror, and converts it into a signal for each wavelength. It is composed of a charge storage type CCD line sensor having 1024 unit light-receiving units that output in this manner, and is provided on one side of the dark box 24 so as to protrude laterally outward. The spectroscope controller 23A is configured to perform signal processing and the like for outputting the accumulated charge for each unit light receiving unit accumulated by the light receiving sensor 23 to the outside.

  As shown in FIG. 10, the light-receiving shutter mechanism 17 includes a disk 25 in which a plurality of slits 24 are radially formed in a state of being rotated around a vertical axis by a shutter switching electric motor 26. When the slits 24 overlap with each other, the spectroscope 18 is in an open state that allows light to pass therethrough, and when the position of the slit 24 is shifted, it enters a blocking state that blocks light. A light aperture 20 is formed, and the disc 25 is arranged in a state of sliding in close contact with the light entrance 20 so as not to leak light. That is, the light receiving shutter mechanism 17 is provided in the state of being close to the light entrance 20 for the spectroscope 18.

  As shown in FIG. 11, the filter switching mechanism 19 is provided in a state of being in close contact with the light receiving shutter mechanism 17, that is, on the upper side of the light incident direction with respect to the light receiving shutter mechanism 17. In addition, at least two wavelengths within the light receiving wavelength range of the light receiving sensor 23, the opening A1 through which the incident light passes as it is, three light reducing action portions A2, A3, A4 each consisting of ND filters having different light attenuation rates, and Each of the wavelength calibrating operation portions A5 as wavelength calibrating bodies having a peak portion of the light attenuation rate is provided in the rotating body 27 in a state of being spaced apart in the circumferential direction at a position equidistant or substantially equidistant from the center of the rotating body 27. A filter switching electric motor 28 for rotating the rotating body 27 is provided. Then, the control unit 3 drives the switching electric motor 28 to rotate the rotating body 27 to select any one of the opening A1, the dimming operation units A2, A3, and A4, and the spectral In this configuration, the light incident on the vessel 18 is switched to a state where it passes through either of them. When the wavelength calibration process of the light receiving sensor 23 is performed, the filter switching electric motor 28 is driven to rotate the rotating body 27 so that the light incident on the spectroscope 18 passes through the wavelength calibration operation part A5. It is the structure which switches to the state to perform. Therefore, the wavelength calibration body that can obtain the wavelength calibration light having the peak portions at at least two wavelengths within the light receiving wavelength range of the light receiving sensor 23, until the transmitted light from the measurement object enters the light receiving sensor 23. It is configured to be switchable between a state located in the optical path and a state retracted from the optical path.

  Temperature adjusting devices 60a and 60b are provided as temperature adjusting means for adjusting the temperature of the light receiving unit 2, and the temperature adjusting devices 60a and 60b are formed on the outer periphery of the light receiving unit 2 inside the casing 2A. The temperature is adjusted with respect to Q. Further, a pair of temperature adjusting devices 60 a and 60 b are provided in a state where the temperature adjusting devices 60 a and 60 b are distributed and positioned on both lateral sides of the light receiving unit 2.

  More specifically, as shown in FIGS. 7 and 8, temperature adjusting devices 60 a and 60 b that adjust the temperature of the light receiving unit 2 are provided on the left and right sides of the light receiving unit 2. Each of these temperature control devices 60a and 60b includes a Peltier element pt for temperature adjustment, a blower fan 62 for air conditioning, and an exhaust fan 66 for releasing exhaust heat.

First, the Peltier element pt will be described.
As shown in FIG. 13, the Peltier element pt is applied with a voltage between both terminals, and when a current is passed, the temperature of one side surface is increased and the temperature of the other side surface is decreased due to the Peltier effect. If the polarity is changed, the temperature of the side surface on one side decreases and the temperature of the side surface on the other side increases. Thus, the temperature control is performed by applying a voltage as shown in FIG. 13 (a) with the side surface on one side located on the inner side of the casing 2A as the temperature control surface 61a and the other side surface as the exhaust surface 61b. Since the temperature of the working surface 61a is higher than the ambient temperature, the light receiving unit 2 can be heated by blowing the air around the temperature adjusting working surface 61a into the light receiving unit 2 by the blower fan 62. . Further, as shown in FIG. 13B, since the temperature of the temperature control surface 61 a is lower than the ambient temperature by applying a voltage, the air around the temperature control surface 61 a is received by the blower fan 62 to receive the light receiving unit 2. The light receiving unit 2 can be cooled by blowing air into the interior. The air around the exhaust working surface 61b of the Peltier element pt is discharged to the outside of the casing 2A by the exhaust fan 66, so that the temperature adjustment as described above by the temperature control working surface 61a can be performed satisfactorily. I can do it.

  In other words, in the fan casing 62a that covers the periphery of the blower fan 62, the air inlets 62b are formed in the opposite side wall portions of the light receiving portion 2 located in the casing 2A. After the air in the casing 2A of the light receiving unit 2 is sucked into the fan casing 62a from the intake port 62b by the airflow action of the light receiving part 2 and passed through the periphery of the temperature control action surface 61a of the Peltier element pt, the spectroscope 18 is arranged. It is comprised so that it may blow out to the established area.

  Temperature sensors 63a and 63b are provided as temperature detecting means for detecting the temperature of the light receiving unit 2, and the control unit 3 maintains the temperature of the light receiving unit 2 detected by the temperature sensors 63a and 63b at the target temperature. Thus, the operation of the temperature control devices 60a and 60b is controlled. That is, temperature sensors 63a and 63b are respectively provided corresponding to the pair of temperature adjusting devices 60a and 60b at both the left and right sides in the casing 2A of the light receiving unit 2, and the control unit 3 controls the temperature sensors 63a. , 63b, the temperature of the air layer Q, that is, the temperature of the light receiving unit 2 is controlled so that the operation of the temperature adjusting devices 60a, 60b is controlled separately.

  In other words, the switching drive devices 68a and 68b for switching the polarity of the voltage applied to the Peltier element pt and changing and adjusting the pulse width of the applied pulse signal based on the command from the control unit 3 are described above. A pair is provided corresponding to the pair of temperature control devices 60a and 60b. Then, for example, when the outside air temperature is low, such as in winter, the control unit 3 switches the polarity of the applied voltage so that the heating is performed as shown in FIG. Control information is commanded to the switching drive circuit so that a pulse signal of the set voltage is applied to the positive terminal. As a result, the temperature-adjusted air is ventilated toward the inside of the light receiving unit 2 so that the heating can be adjusted. At that time, when the temperature deviation between the temperature detected by the temperature sensors 63a and 63b and the target temperature is large, the ON time of the pulse signal is lengthened, and when the temperature deviation is small, the ON time of the pulse signal is shortened. By executing the PWM control, the temperature adjustment control is performed so that the temperature adjustment capability is automatically adjusted and the light receiving unit 2 reaches the target temperature.

  In addition, when the outside air temperature is high, such as in summer, the polarity of the applied voltage is switched so as to achieve the cooling state as shown in FIG. 13 (b), the negative terminal is grounded, and the set voltage pulse signal is connected to the positive terminal. The light receiving unit 2 can be cooled by applying. At this time, the temperature adjustment control as described above is performed as in the case of the heating adjustment.

  While the temperature adjustment control is performed, all of the blower fan 62, the exhaust fan 66, and the circulation fan 67 are always rotated.

  In addition, the temperature adjusting device 60a located on the side where the light receiving sensor 23 is close to the pair of temperature adjusting devices 60a and 60b is directly blown by the air blowing fan 62 provided in the temperature adjusting device 60a. An air blowing guide plate 64 is provided to flow and guide the air layer Q so as to prevent the air from being blown to the air layer Q. The air whose temperature has been adjusted by the temperature adjusting device 60a in this way is directly blown onto the light receiving sensor 23, thereby preventing the temperature of the light receiving sensor 23 from changing suddenly and changing the value of the dark current. I am doing so.

  In addition, circulation fans 67 are provided in the casing 2A to make the temperature distribution uniform as much as possible by circulating air inside the casing 2A at both the left and right side portions on the lower side inside the casing 2A.

  And the said control part 3 sets the high temperature side target temperature based on the switching command by the target temperature switch 65 as a switching command means, and the high temperature side adjustment state which controls the action | operation of the temperature regulator 60a, 60b, The low temperature side target temperature lower than the high temperature side target temperature is set to switch to the low temperature side adjustment state in which the operation of the temperature adjustment devices 60a and 60b is controlled. More specifically, as shown in FIG. 12, when the target temperature switch 65 is manually operated to switch to the high temperature side adjustment state, the high temperature side target temperature (for example, 30 ° C.) is set. The operation of the temperature adjusting devices 60a and 60b is controlled. When the target temperature switching device 65 is operated to switch to the low temperature side adjustment state, the low temperature side target temperature (for example, 10 ° C.) is set to control the operation of the temperature adjustment devices 60a and 60b.

  That is, the temperature adjustment control described above is performed so that the temperature of the light receiving unit 2 becomes the target temperature (30 ° C.) by switching to the high temperature side adjustment state in summer and performing the low temperature side adjustment in winter. By performing measurement processing by switching to the state, temperature adjustment control is performed so that the temperature of the light receiving unit 2 becomes the target temperature (10 ° C.). In this way, the target temperature will be different between summer and winter, but the types of target fruits and vegetables are different between summer and winter, and the calibration formulas described later are also set for each. Since it is used, the accuracy of quality evaluation does not decrease. Note that the target temperature on the high temperature side is not limited to 30 ° C., and may be any other temperature, and the target temperature on the low temperature side is not limited to 10 ° C., but other temperatures. It may be.

  Therefore, the temperature adjusting device 60a is maintained so that the temperature of the light receiving unit 2 detected by the temperature sensors 63a and 63b is maintained at the target temperature by the control configuration as described above of the control unit 3 and the switching drive circuit 68. , 60b is controlled.

  Then, the vertical position adjusting mechanism 29 as vertical position adjusting means capable of adjusting the position of the light projecting unit 1 and the light receiving unit 2 in the vertical direction integrally, and each of the light projecting unit 1 and the light receiving unit 2 are separately provided in the device frame. Horizontal position adjusting means whose position is adjustable along the direction of approaching and moving away from the measurement object located at the measurement location with respect to the body F, that is, in the horizontal direction and perpendicular to the transport direction of the transport conveyor 4. A horizontal position adjusting mechanism 30 is provided.

  Next, the vertical position adjusting mechanism 29 will be described. As shown in FIG. 1 to FIG. 3, an apparatus frame F assembled in a rectangular frame shape so as to surround the outer peripheral portion of the quality evaluation apparatus is provided. The fixed support rods 31 are provided in a suspended state, and a support base 32 is attached to the lower ends of the four fixed support rods 31. A lifting platform 34 is supported on the four fixed support rods 31 by four sliding support portions 33 so as to be slidable in the vertical direction. Further, a feed screw 35 supported in a suspended state from an upper side portion of the apparatus frame F is rotatably provided by an electric motor 36, and a female screw member 37 provided on the lifting platform 34 is provided on the feed screw 35. They are screwed together, and the lifting platform 34 can be adjusted to move up and down to an arbitrary position by rotating the feed screw 35 with an electric motor 36. The feed screw 35 is also configured to be rotatable by a manual operation handle 38.

Next, the horizontal position adjusting mechanism 30 will be described.
As shown in FIG. 4, the lifting platform 34 is provided with two guide bars 39 extending along the direction in which the light projecting unit 1 and the light receiving unit 2 are arranged, and the light projecting unit assembled in a unit shape. The support members 40 and 41 as the pair of attachment parts to which the part 1 and the light receiving part 2 are detachably attached are supported by the guide rods 39 so as to be slidable. Each guide bar 39 is connected by a connecting tool 39a at both ends in the longitudinal direction. In addition, two feed screws 42 and 43 extending along the direction in which the light projecting unit 1 and the light receiving unit 2 are arranged on the lift 34 can be rotated by horizontal position adjusting motors 44 and 45, respectively. Female screw portions 46, 47 provided in the support members 40, 41 are screwed into the feed screws 42, 43, and the electric motors 44, 45 respectively connect the feed screws 42, 43 to the feed screws 42, 43. By separately rotating in the forward and reverse directions, the support members 40 and 41 can be adjusted in position along the horizontal direction perpendicular to the transport direction of the transport conveyor 4. Accordingly, the light projecting unit 1 and the light receiving unit 2 respectively attached to the support members 40 and 41 respectively rotate the feed screws 42 and 43 forward and backward by the electric motors 44 and 45, respectively. That is, it is possible to change and adjust the relative position in the direction approaching and separating from the measurement location.

  In addition, a reference body 49 for light quantity calibration is provided in a state of being supported by a support member 48 extending from the support base 32 and positioned above the passing portion of the object to be measured M on the conveyor 4. ing. The reference body 49 is composed of an optical filter having a predetermined dimming rate composed of opal glass, and always performs the same measurement as long as the light projecting state of the light projecting unit 1 and the light receiving state of the light receiving unit 2 are the same. A value can be obtained, but if there is a variation in the measured value due to the secular change in the light receiving sensor 23, a different measured value is obtained. Therefore, by receiving the light transmitted through the reference body 49, such a secular change is caused. It is possible to obtain a measurement value serving as a reference in a state in which fluctuation is taken into consideration.

  Therefore, when the feed screw 35 is rotated by the electric motor 36, the lifting / lowering base 34 is adjusted to move up / down. Accordingly, the light projecting unit 1 and the light receiving unit 2 supported by the lifting / lowering base 34 are integrated. It can be adjusted up and down, and by changing and adjusting the overall vertical position of the conveyor 4, it is measured at the normal measurement position that acts on the measurement object M and the reference body 49 for light quantity calibration. It is possible to switch to the calibration position where it operates. Further, by rotating the electric motors 44 and 45, the position of the light projecting unit 1 and the light receiving unit 2 can be adjusted along the horizontal direction perpendicular to the transport direction of the transport conveyor 4.

  The transport conveyor 4 for placing and transporting the object to be measured M is rotationally driven by an electric motor 4b, and as shown in FIG. An optical passage detection sensor 50 that outputs a detection signal when it is detected that the measurement object has arrived is provided. That is, the passage detection sensor 50 is arranged with the light emitter 50a and the light receiver 50b distributed to the left and right sides of the transport conveyor 4, and light is detected when there is no object to be measured. Therefore, it is configured to detect that the object to be measured has arrived. The transport speed of the transport conveyor 4 is detected by a rotary encoder E.

  In this quality measuring device, for example, a plurality of varieties of fruit and vegetables with different light attenuation rates can be measured as the object M to be measured. It is configured to perform artificially. That is, as shown in FIG. 12, an artificially operated type changeover switch 51 is provided that artificially switches the setting position in accordance with the type of change, and setting information of the type changeover switch 51 is input to the control unit 3. The control unit 3 changes the operation content for control as described later in accordance with the setting information.

  The control unit 3 is configured to execute processing for obtaining the internal quality of the measurement object M based on detection information of the light receiving sensor 23 and processing for controlling the operation of each unit. Therefore, the evaluation means 101 for obtaining the quality evaluation value of the measurement object is configured by such a control configuration in the control unit 3.

  The control unit 3 projects light to a reference body 49 for light quantity calibration instead of the object to be measured, receives light transmitted from the reference body 49, and receives reference light reception information for light quantity calibration. Control the operation of each unit to measure the light reception information for quality evaluation by projecting light to the object to be measured, and the reference information measurement mode for light quantity calibration that controls the operation of each unit to measure, and A quality information measurement mode for obtaining quality information of an object to be measured based on the light reception information for reference and the light reception information for quality evaluation, and the light is projected to the wavelength calibration operation unit A5 and transmitted through the wavelength calibration operation unit A5. Thus, it is configured to be switched to a wavelength calibration reference information measurement mode for controlling the operation of each unit so as to receive light and measure reference information for wavelength calibration.

The processing of the control unit 3 in the light quantity calibration reference information measurement mode will be described.
In the light quantity calibration reference information measurement mode, the positions of the light projecting unit 1 and the light receiving unit 2 are shown in FIG. 5 by the vertical position adjustment mechanism 29 in a state where the conveyance of the measurement object M by the conveyor 4 is stopped. Switch to the calibration measurement position. In addition, the filter switching mechanism 19 is switched so that the light attenuation rate set in advance according to the product set by the switching operation tool 51 is obtained. Further, the light projection state in the light projecting unit 1 such as the adjustment position of the irradiation range by each adjusting plate 8 is set to a condition corresponding to the commanded product type.

  Further, the light receiving shutter mechanism 17 is switched to the open state, the light from the light projecting unit 1 is irradiated on the reference body 49 in place of the object M, and the transmitted light after passing through the reference body 49 is irradiated. Then, the spectral spectrum data obtained by performing the spectrum with the light receiving sensor 23 and receiving the split light is measured as reference spectral spectrum data as light receiving information for reference for light quantity calibration. At this time, the detection value (dark current data) of the light receiving sensor 23 in the non-lighted state where the light is blocked is also measured. That is, the light receiving shutter mechanism 17 of the light receiving unit 2 is switched to the shielding state, and the detection value for each unit pixel of the light receiving sensor 23 at that time is obtained as dark current data.

  At this time, the operation of the light receiving sensor 23 is controlled so as to execute a sending process for sending out the accumulated charge after the light receiving sensor 23 executes the charge storing process for a set time, but the light receiving sensor 23 performs the charge storing process. When performing, the operation is controlled so that the light receiving shutter mechanism 17 is switched from the shielded state to the open state, and the open state is maintained for the duration of the open maintenance time T2 and then returned to the shielded state. This open maintenance time T2 is configured to change a plurality of types of objects to be measured M having different dimming rates in accordance with the types.

Next, processing of the control unit 3 in the quality information measurement mode will be described.
In this quality information measurement processing mode, the vertical position adjustment mechanism 29 is operated to switch the lifting / lowering base 34 to the normal measurement position, and the object to be measured M is conveyed by the conveyor 4. At that time, the elevation position is changed and adjusted according to the commanded product type. In other words, since the size of the object to be measured differs depending on the type of object to be measured, the position where the light projecting unit 1 projects light and the position where the light receiving unit 2 receives transmitted light are adjusted to appropriate positions. is there.

  Then, as shown in FIG. 15, the control unit 3 finishes obtaining light reception information for quality evaluation as described later when the measurement object does not exist at the measurement location and even when the measurement object exists at the measurement location. In this case, the charge is always accumulated in the light receiving sensor 23 until the set time for charging has elapsed from the start timing of charging, and then the charge accumulated in the light receiving sensor 23 is released until the set time for discharging has elapsed. It is configured to control the operation of the light receiving sensor 23 so as to repeatedly execute the charge accumulation / discharge process every set cycle T1. Further, after detecting that the leading position of the measurement object has reached the near side position based on the detection information of the passage detection sensor 50, the measurement object moves to the measurement point P based on the detection information of the rotary encoder E. It is comprised so that it may determine.

  When it is determined that the object to be measured M has reached the measurement location in this way, the charge accumulation discharge process is not repeatedly executed, but the charge accumulated in the light receiving sensor 23 until the set time for discharge elapses from that point. Thereafter, measurement charge accumulation processing for accumulating charges to be used as light reception information for quality evaluation in the light receiving sensor 23 is executed until the set time for measurement elapses. In addition to the switching of the operation of the light receiving sensor 23, the control unit 3 switches the light receiving shutter mechanism 17 from the shielded state to the opened state when the measured object M reaches the measurement point P, and opens the opened state. The operation of the light receiving shutter mechanism 17 is controlled so as to return to the shielding state after maintaining the state until the measurement set time T2 for charge accumulation elapses. In this way, the light received by the light receiving unit 2 from the light emitted from the light projecting unit 1 and transmitted through the object to be measured until the set time T2 for measurement is received by the light receiving sensor 23 and accumulated. be able to. Then, after the set time T2 for measurement elapses, the accumulated charges are taken out and the received light amounts for different wavelengths are measured to obtain measured spectral spectrum data.

And the arithmetic processing which analyzes the internal quality of the to-be-measured object M is performed using the spectral analysis method which is a well-known technique based on the reference | standard spectral spectrum data, dark current data, and measurement spectral spectrum data which were obtained in this way. It is configured as follows.
That is, using the reference spectral spectrum data obtained in the reference data measurement mode obtained as described above and the dark current data, the absorbance spectral data for each wavelength obtained is obtained, and the Obtain the second derivative of the absorbance spectrum data. Specifically, absorbance spectrum data corresponding to the light reception information obtained for each unit light receiving unit of the light receiving sensor 23 is obtained. Of the second derivative value of the absorbance spectrum data obtained in this way, the second derivative value of a specific wavelength for calculating the component and the preset calibration equation are used as the quality information of the object to be measured. It is configured to execute a quality evaluation process for calculating a component amount corresponding to the sugar content contained in the product M and a component amount as a quality evaluation value corresponding to the acidity.

  When the absorbance spectrum data d is Rd as the reference spectrum data, Sd as the measured spectrum data, and Da as the dark current data,

[Equation 1]
d = log [(Sd−Da) / (Rd−Da)]

  It is calculated by the following formula. And it contains in the to-be-measured object M using the value of a specific wavelength among the values which carried out the second derivative of the absorbance spectrum data d obtained by doing in this way, and the calibration formula as shown in following Formula 2. A calibration value for calculating the amount of the component corresponding to the sugar content or acidity is obtained.

[Equation 2]
Y = K0 + K1 · X (λ1) + K2 · X (λ2)

However,
Y; calibration value corresponding to the component amount K0, K1, K2; coefficients X (λ1), X (λ2); second derivative of absorbance spectrum at specific wavelength λ

  A specific calibration equation, specific coefficients K0, K1, K2, wavelengths λ1, λ2, and the like are preset and stored for each component for which the component amount is calculated. The calibration value (component amount) of each component is calculated using a specific calibration formula.

Next, processing of the control unit 3 in the wavelength calibration information measurement mode will be described.
In this wavelength calibration information measurement mode, the filter switching mechanism is switched to a state in which the light toward the spectroscope 18 passes through the wavelength calibration operation part A5 while the conveyance of the object M to be measured by the conveyor 4 is stopped. The light receiving shutter mechanism 17 is switched to the open state. Then, the light from the light projecting unit 1 is irradiated onto the wavelength calibration operation unit A5, and the spectral spectrum data obtained by receiving the transmitted light by the light receiving sensor 23 is measured as spectral spectrum data for wavelength calibration. Further, the control unit 3 detects two spectral peak positions whose wavelengths are known, and executes wavelength calibration processing for calibrating the light reception wavelength of each unit light receiving unit of the light receiving sensor 23 based on the detection information.

  Such wavelength calibration spectral data measurement processing and wavelength calibration processing are performed, for example, at the start of a day's work or when the variety of fruit and vegetable to be measured is switched. The control unit 3 executes the quality evaluation process based on the correspondence between each unit light receiving unit after the wavelength calibration and the received light wavelength after performing the wavelength calibration process. It is configured.

[Another embodiment]
Hereinafter, other embodiments are listed.

(1) In the above embodiment, a pair of the temperature adjusting means is provided in a state where the temperature adjusting means is distributed and positioned on both lateral sides of the light receiving means, and the temperature control means is configured to control the pair of temperature adjusting means. However, the present invention is not limited to such a configuration, and only one temperature adjusting unit may be provided, or three or more temperature adjusting units may be provided.

(2) In the above embodiment, an example is provided in which a casing that surrounds the light receiving means in a state where an air layer is formed is provided, and the temperature adjusting means is configured to regulate the temperature of the air layer. However, the present invention is not limited to such a configuration, and a configuration that directly controls the temperature of the light receiving unit may be employed.

(3) In the above embodiment, an example using a Peltier element as the temperature adjusting means has been illustrated, but the configuration is not limited to this configuration, and the air medium is configured to circulate and circulate between the condenser and the compressor. It may be a temperature adjusting means having another configuration such as a heat pump type air conditioner.

(4) In the above embodiment, the temperature control unit 100 and the evaluation unit 101 are configured by using the control unit 3 that controls the operation of each unit. Separately from the control unit 3 constituting the above, a dedicated device that performs only temperature control may be provided.

(5) In the above embodiment, as the switching command means, the human-operated target temperature switch 65 is provided, and the target temperature switch 65 switches between the high temperature side adjustment state and the low temperature side adjustment state. For example, a control device having a calendar function is provided, and for example, May to October is set as summer and November to April is set as winter. It may be configured to switch to the side adjustment state. In addition to this, it may be configured to automatically switch to the high temperature side adjustment state or the low temperature side adjustment state based on the outside air temperature.

  Also, the following configuration may be used. Instead of setting one type of high temperature side target temperature in the high temperature side adjustment state and setting one type of low temperature side target temperature in the low temperature side adjustment state, for example, a plurality of high temperature side target temperatures may be set. One of the target temperatures may be set, or one of a plurality of target temperatures may be set as the low-temperature target temperature.

(6) In the said embodiment, a light projection part and a light-receiving part are distributed and arranged by the right-and-left both sides of a conveyance conveyor, and light is projected sideways from the lateral one side outward with respect to the to-be-measured object located in a measurement location. Thus, the light transmitted through the object to be measured is received by the light receiving unit. However, instead of such a configuration, the following configuration may be used.

  As shown in FIG. 16, a pair of light projecting units 1, 1 are distributed and arranged on the left and right sides of the conveyor 4, and light is projected by the light projecting units 1, 1 to the measurement object located at the measurement location. The through-hole 52 penetrating up and down is formed in the mounting body 4a for placing and supporting the object to be measured on the transport conveyor 4, and the lower side is passed through the through-hole 52 after passing through the object to be measured. It is good also as a structure provided in the state located in the downward side of the measurement location in the conveyor 4 so that the light-receiving action part in the light-receiving part 2 may be received. In the example shown in FIG. 16, the light emitted downward through the through hole 52 is guided to the light receiving unit 2 by the optical fiber 53. In addition, the light receiving unit 2 may be arranged on the lower side of the conveyor 4 so that light emitted downward through the through hole 52 is directly incident on the light receiving unit 2.

(7) In the above embodiment, the halogen lamp is used as the light source of the light projecting means. However, the present invention is not limited to this, and various light sources such as a mercury lamp and a Ne discharge tube may be used. The sensor is not limited to the CCD line sensor, and other detection means such as a MOS line sensor may be used.

(8) In the above embodiment, the light receiving information for quality evaluation and the light receiving information for reference are measured based on the transmitted light from the object to be measured, but instead of this configuration, the light from the object to be measured M is measured. The light reception information for quality evaluation and the light reception information for reference may be measured based on the reflected light.

(9) In the above embodiment, the sugar content and the acidity are exemplified as the internal quality of the measurement object M. However, the internal quality is not limited to this, and other internal quality such as taste information may be measured.

Front view of internal quality evaluation equipment Side view of internal quality evaluation equipment Side view of internal quality evaluation equipment Partially cutaway front view of internal quality evaluation equipment Front view of internal quality evaluation equipment Notched plan view of the light emitting part Partial cutaway plan view of the light receiving part Partially cutaway side view of the light receiver Schematic diagram showing the configuration of the spectrometer Diagram showing light receiving shutter mechanism Diagram showing filter switching mechanism Control block diagram Principle of temperature control device Plan view showing installation Timing chart of measurement operation Front view of internal quality evaluation apparatus according to another embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light projection means 2 Light reception means 60a, 60b Temperature adjustment means 63a, 63b Temperature detection means 65 Switching command means 100 Temperature control means 101 Evaluation means Q Air layer

Claims (4)

Light projecting means for projecting light onto the object to be measured, light receiving means for separating the transmitted light or reflected light from the object to be measured and receiving the dispersed light, and the object to be measured based on the measurement result of the light receiving means A spectroscopic analysis apparatus comprising an evaluation means for obtaining a quality evaluation value of
The temperature detecting means for detecting the temperature of the light receiving means, the temperature adjusting means for adjusting the temperature of the light receiving means, and the temperature so that the temperature of the light receiving means detected by the temperature detecting means is maintained at a target temperature. Temperature control means for controlling the operation of the adjusting means,
Based on the switching command of the switching command means, the temperature control means sets a high temperature side target temperature to control the operation of the temperature adjusting means, and a low temperature lower than the high temperature side target temperature. A spectroscopic analyzer configured to be switchable to a low temperature side adjustment state in which a target temperature on the side is set and the operation of the temperature adjustment means is controlled.   The casing according to claim 1, wherein a casing is provided to surround the light receiving means in a state where an air layer is formed on an outer peripheral portion of the light receiving means, and the temperature adjusting means is configured to regulate the temperature of the air layer. Spectroscopic analyzer.   3. The spectroscopic apparatus according to claim 2, wherein a pair of the temperature adjusting means is provided in a state where the temperature adjusting means is distributed and positioned on both lateral sides of the light receiving means, and the temperature control means controls the pair of temperature adjusting means. Analysis equipment.   The spectroscopic analyzer according to any one of claims 1 to 3, wherein the object to be measured is fruit and vegetables.

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