JPH01142441A - Apparatus for measuring polishing degree of grain of rice - Google Patents

Abstract

PURPOSE:To enhance measuring accuracy, by making the density of the grains of rice in a simple case almost constant at every sample by vibrating the sample case at the time of measurement. CONSTITUTION:A light source part 4 consisting of a halogen lamp 2 and a condensing lens 3 is provided to an outer box 1 on one side thereof and a measuring part 7 is arranged at a place near to the center from the light source part 4. A case holding frame 9 holding a sample case 8 and a vibration apparatus 14 for vibrating the case 8 along with the holding frame 9 are provided to the measuring part 7. At the time of measurement, the sample case 8 is vibrated after insertion and the light from a light emitting fiber 24 is detected by a transmitting photodiode 31 and a reflecting photodiode 30 to calculate reflectivity and transmissivity. The calibration of the diodes 30, 31 is preliminarily performed using the empty case, a monitor photodiode 32 and a fiber 29. By this method, the density of the grains of rice becomes constant and measuring accuracy is enhanced.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a rice grain polishing level measuring device.

[Conventional technology]

Rice polishing is an action that sequentially removes the structure of the rice grain from the outer periphery toward the inside, exposing the internal structure of the rice grain. It is expressed simply by the word "yield", and is generally expressed by the following formula.

Yield = (total weight of white rice / total weight of brown rice) x 100 The quality of this yield depends on the properties of the raw brown rice and rice milling technology, but normally the bran layer accounts for 6-7% of the total brown rice, and the embryo accounts for 2-3% of the total brown rice.
% (see Figure 4), so if the raw materials are ideal, the yield will be around 90%. Factors affecting brown rice properties that affect the yield include: - Thickness and hardness of the bran layer - Size and detachment of the embryo - Contamination rate of damaged grains (split grains, etc.) and immature grains - Stiffness and moisture content of rice etc.

In other words, yield refers to the yield of a product (white rice) relative to raw brown rice, and does not determine the quality of rice (commercial value) after milling, for example, by uneven pounding.

On the other hand, the term milling degree (milling rate) is used to judge the extent to which the bran layer and embryo have been removed during rice polishing, or in other words, the degree of rice quality (commercial value). There is.

The degree of polishing will be explained with reference to cross-sectional views of brown rice shown in FIGS. 4 and 5. Brown rice flour consists of a starch layer that forms the core, that is, the endosperm, and a bran layer that covers the outer periphery of the starch layer.
40μ).

Furthermore, the outer bran layer consists of the pericarp forming the outer wall and the seed coat on the inner wall surface, and the inner bran layer consists of the ectosperm and the aleurone layer. The polishing level is defined as 100% when all of the inner bran layer, including the aleurone layer, is removed, and brown rice is defined as 0%. However, the aleurone layer contains proteins and fats and oils, which are one of the components of taste, so the aleurone layer is an important component for white rice for base plates, and the aleurone layer is an important component for polished rice for base plates. This is what is called starch white rice, which is suitable for sake brewing but not for base plate use.

Therefore, ideal rice milling is to mill rice with some aleurone layer remaining, that is, milled rice with a polishing degree of about 85% is the most suitable milled rice for base plates.

[Problem that the invention seeks to solve]

By the way, as the rice polishing action progresses from the outer bran layer to the inner bran layer,
The whiteness of rice grains gradually increases, and since this rate of increase is almost proportional, conventionally, the degree of whiteness of rice grains has been measured and used as the degree of whitening. A whiteness meter that measures the degree of whiteness uses an integrating sphere and receives the amount of reflected light from the amount of light irradiated on the sample rice with a phototube to determine the reflectance, and the measured value is obtained using ultrafine powder of magnesium oxide. It is expressed as a percentage when whiteness is 100 and pure black is O.

However, the degree of whiteness determined by a whiteness meter is only the amount of light reflected from the surface of the rice grain, and does not take into account the amount of light that passes through the rice grain, and is a value unrelated to the degree of whiteness. For example, white rice with a slight amount of white bran attached immediately after milling will have a much higher white discoloration value than white rice that has been sufficiently removed and polished. This is because when the rice grain surface becomes glossy and smooth, the amount of diffusely reflected light decreases due to the tendency of surface reflection.
Since this value is opposite to the progressing degree of whitening, it proves that this value is independent of the degree of whitening. In other words, white discoloration is the amount of diffusely reflected light, and it must be said that it is unreasonable to consider this white discoloration as whiteness.

In order to solve this problem, a proposal was made in 1983-
This is a rice grain milling degree measuring device disclosed in Publication No. 100751, which has a measuring tank equipped with a load cell in the feed section of the raw material, and uses this measuring tank to determine the volumetric weight, and also measures the milling degree via a volumetric gravity circuit. This method corrects the value and requires a measuring tank, etc., which inevitably results in a large-scale measuring device.

In view of this point, the technical object of the present invention is to provide a compact and accurate rice grain polishing level measuring device.

[Means for solving problems]

In order to solve the above problems, the first invention of the present application is as follows: (a) An optical fiber for light projection is interposed between the light source and the measuring section.

Mouth, i! The other end of each optical fiber for reflected light and transmitted light, each of which has a light-receiving element electrically connected to the amplification part at one end, faces the I constant part.

C. A calculation section and a display section are provided connected to the amplification section.

2. The measuring section is equipped with a vibrating device to keep the density of rice grains in the sample case almost constant for each sample.

In addition, the second invention of the present application takes the following technical measures: (a) An optical fiber for light projection is interposed between the light source section and the measurement section.

The other end of each optical fiber for reflected light and transmitted light, each of which has a light-receiving element electrically connected to the amplification part at one end, faces the opening and measurement part.

C. A calculation section and a display section are provided connected to the amplification section.

2. The light source section is provided with the other end of a monitoring optical fiber having one end of a light receiving element electrically connected to the amplification section.

This technical measure was taken.

[For production]

When rice grains (white rice) as a sample are placed in the sample case and the sample case is attached to the measurement unit, the sample case is vibrated by the vibration device installed in the measurement unit, reducing the gaps between the rice grains in the sample case. As a result, the rice grains become stuck together, creating a somewhat dense state. This reduces the difference in rice grain density due to differences in grain surface condition and size, and makes the density almost constant for each sample.
Minimize measurement errors due to differences in sample density.

In addition, in the second invention, in order to eliminate measurement errors caused by changes in the light intensity of the light source mainly due to changes in the temperature near the light source during measurement, the amount of light taken in from the monitoring optical fiber provided in the light source is constantly adjusted. The brightness value is corrected according to the amount of change in the amount of light.

(Embodiment of the Invention) Hereinafter, a preferred embodiment of the present invention will be described based on the drawings. Fig. 1 is a plan view showing a part of this embodiment in a cutaway section, Fig. 2 is a perspective view of the sample case in Fig. 1, and Fig. 3 is a block diagram conceptually showing this embodiment. .

A so-called halogen lamp 2 that emits white light is located on one side of the outer box 1 which is equipped with a power supply section 6 consisting of an on/off switch 5, etc.
A light source section 4 consisting of a condensing lens 3 and the like is provided, and the light source section 4
A measuring section 7 is disposed near the center. The measuring section 7 is
A sample case 8 is recessed so as to be insertable therein, and a case holding frame 9 for holding the sample case 8 is supported by a plurality of springs 10 inside the recess. In addition, the case holding frame 9 is provided with a limit switch 11 that is activated when the sample case 8 is inserted, and a vibrator is installed in a small gap between a protrusion 13 formed by protruding one side of the case holding frame 9. -12 is fixed. As a result, when the sample case 8 is inserted into the case holding frame 9 and the limit switch 11 is ONL, the vibrator 12
is activated, and an imaging device 14 is formed that vibrates the sample case 8 together with the case holding frame 9 via the protrusion 13.

Sample case 8 will be explained below (see FIG. 2). The sample case 8 consists of a body 16 having a handle 15 formed at one end, a lid 18 attached to the other end of the body 16 so as to be openable and closable, and a saucer 19 into which a sample is placed. A circular hole 20 into which the saucer 19 is inserted is bored in the center of the body 16, and a transparent window 21 made of colorless quartz glass or the like is provided in the center of the lid 18 facing the circular hole 20. On the other hand, the bottom surface of the saucer 19 also has a transparent bottom 22 made of the same material as the transparent window 21, and a flange 23 is formed at the upper end.

On the transparent window 21 of the sample case 8 in the measurement section 7, the other ends of a pair of light emitting fibers 24 and 24, one end of which is connected to the vicinity of the condenser lens 3 of the light source section 4, are exposed, and the amount of light from the halogen lamp 2 is monitored. , is formed so as to project light onto the rice grains (sample) in the saucer 19 through the transparent window 21. Further, one end of the reflective receiving fiber 27 is placed directly above the transparent window 21 of the sample case 8 of the measuring section 7, and the transmitting receiving fiber 27 is placed directly below the circular hole 20 of the sample case 8.
Furthermore, one end of a monitor fiber 29 is provided near the condenser lens 3 of the light source section 4 along with a pair of light projection fibers 24.

An amplification section 25 including an amplifier (not shown), and a calculation section 26 including an A/D converter, a CPLI, a memory (none of which are shown), etc. are arranged near the measurement section 7 in the outer box 1. The amplifier section 25 includes a reflection photodiode 30, a transmission photodiode card 31, and a monitoring photodiode 32 connected to the other ends of the reflection receiving fiber 27, the transmission receiving fiber 28, and the monitoring fiber 29, respectively. At the same time, each of these photodiodes 30 to 32 is electrically connected to an amplifier in the amplifying section 25, respectively. Note that each of the photodiodes 30 to 32
may be electrically connected to the amplifier within the amplifier section 25, and does not necessarily need to be provided within the amplifier section 25 as in this embodiment.

A display section 33 is provided connected to the calculation section 26 .

That is, the display section 33 includes a digital panel meter (hereinafter simply referred to as "Digispring") 35 for displaying the number of times provided on the operation panel 34, a Digispring 36 for displaying reflectance, a Digispring 37 for displaying transparency, and a Digispring 38 for displaying sharpness. Consisting of

The operation panel 34 includes a digital spring 36 for displaying reflectivity, a digital spring 37 for displaying transparency, and a digital spring 38 for displaying sharpness.
In addition to providing an average switch button 39 and a configuration switch button 40 that are pressed when calculating the average of each measured value displayed on the screen, a ready live 41 that displays a measurable state and a display that a sample case 8 is attached are provided. A light lamp 43 is provided to indicate that the sample lamp 42 and the halogen lamp 2 of the light source section 4 are turned on.

Next, the specific operation in this embodiment will be explained.

When the on/off switch 5 of the power supply section 6 is turned on, the halogen lamp 2 and the light lamp 4 are turned on, and about 10 seconds later, the ready lamp 41 is turned on. When the ready lamp 41 lights up, press the calibration switch button 40 to perform calibration. That is, when the calibration switch button 40 is pressed and the ready lamp 41 turns off, the empty sample case 8 is inserted into the case holding frame 9 of the measuring section 7. When the sample case 8 is installed correctly, the limit switch 11 is set to O.
NL, the sample lamp 42 lights up, but since the calibration switch button 40 is pressed, the vibrator 12 does not operate. At this time, from the light source section 4 to the light emitting fiber 24
The light beam that passes through the transparent window 21 of the sample case 8 of the measurement unit 7 and then the transparent bottom 22 of the saucer 19 reaches the transmission photodiode 31 via the transmission receiving fiber 28, and this amount of light is considered to be 100% transmittance. At the same time, the reflectance is 100 with twice the amount of light taken in from the monitor fiber 29 (all internal optical fibers have the same diameter).
%. This completes the calibration and the ready lamp 41
lights up, and each digital spring 35 to 3 of the display section 33
8 displays all "0".

When the calibration is completed, take out the sample case 8, fill the saucer 19 with polished rice as a sample, and close the lid 1.
8 and insert it into the case holding frame 9 of the measuring section 7. When the sample case 8 is installed in the case holding frame 9 and the limit switch 11 is turned on, the vibrator 12 is activated by a timer (not shown) for a certain period of time, for example, 5 seconds, and the vibration of the vibrator 12 is transmitted through the protrusion 13. The vibration is transmitted to the case holding frame 9, and by causing the case holding frame 9 supported by the spring 10 to resonate, the sample case 8 is caused to vibrate together. When the sample case 8 vibrates, the particles of white rice in the saucer 19 also vibrate, and the gaps between the particles become smaller and clogged, and the white rice blends into each other, settling into a sample with a certain degree of high density due to its own weight.

Measurement starts when the vibrator 12 stops operating, and the reflection photodiode 30 and the transmission photodiode 31 electrically measure the amount of reflected light and the amount of transmitted light from the sample taken in by the reflection receiving fiber 27 and the transmission receiving fiber 28, respectively. It is converted into a signal and output to an amplifier connected to each photodiode. Then, the calculation unit 26 calculates the reflectance and the transmittance based on the ratio of the reflectance and the transmittance variable set at the time of calibration to 100%.

The degree of brightness is calculated from the degree of reflection and the degree of transmittance.If the degree of brightness is 81, the degree of reflection is R, and the degree of transmittance is the king, the degree of brightness S can be determined by the following equation.

S=A -R0+8- TE"F+C A1B, C, DlE and F are coefficients determined experimentally. These coefficients are set for general rice and for several types of special rice, and are switched depending on the sample. You may change it in a microwave, etc. Also, you can set up a program for measuring brown rice, and first,
In some cases, the sample is measured as brown rice, and the data on the reflectance R and transmittance T of the brown rice is used to correct the whiteness of white rice. It is possible to eliminate variations caused by grains and darkened rice.

The reflectivity, transmittance, and polishing degree thus obtained are displayed on the digital spring 35 for displaying the number of times on the display section 33, as well as the number of measurements.
Reflectance display digital spring 36, transparency display digital spring 37
and is displayed on the sharpness display digital spring 38, and simultaneously stored in the arithmetic unit 26.

For the second and subsequent measurements, use sample case 8 in the same manner as the first.
Fill the sample into the receiving tray 19 of
Attach to. In the measuring section 7, the sample is subjected to vibration by the vibrator 12, and the sample exhibits almost the same high density as the first time, and the reflectance and transmittance are measured without measurement errors due to differences in density, and the average When the switch button 39 is pressed, the average value of the measured values up to that point is displayed on each digital spring, the memory of the measured values is cleared, and the next sample is measured.

As the measurement continues in this way, the light intensity of the halogen lamp 2 of the light source section 4 changes due to the ambient temperature or fatigue of each part, but the light intensity of the light source section 4 changes due to the connection of one end to the light source section It is constantly detected by a monitor photodiode 32 and an amplifier via a monitor fiber 29, and when a change occurs in the light intensity at the time of calibration, each measured value is corrected to eliminate measurement errors between multiple measurements. It never occurs.

〔Effect of the invention〕

The first invention is provided with a vibrating device to make the density of rice grains in the sample case almost constant for each sample, thereby preventing measurement errors due to differences in the density of the samples. A monitor optical fiber is installed in the monitor to monitor the light intensity of the light source, and the brightness value is corrected according to changes in the light intensity, so even if the ambient temperature rises over time and the brightness increases, the brightness value can be automatically corrected. This eliminates the need for frequent calibration (allowing accurate whiteness measurements).

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a part of the embodiment of the present invention in a broken cross section, FIG. 2 is a partially enlarged perspective view of FIG. 1, and FIG. 3 is a block diagram conceptually showing the embodiment. Figure 4 is a longitudinal cross-sectional view of brown rice.
FIG. 5 is a partially enlarged view of FIG. 4. 1...Outer box, 2...Halogen lamp, 3...Condenser lens, 4...Light source section, 5...On/off switch, 6
...Power supply section, 7.Measurement section, 8.Sample case, 9.Case holding frame, 10.Spring, 1
1... Limit switch, 12... Vibrator
113...Protrusion, 14...Vibration device, 15...Handle portion, 16...Body, 17...Hinge, 18...
・Lid, 19... saucer, 20... circular hole, 21... transparent window, 22... transparent wall, 23... flange, 24...
...Light emitting fiber, 25...Amplifying section, 26...Calculating section, 27...Reflecting light receiving fiber, 28...Transmitting light receiving fiber, 29...Monitoring fiber, 3
0...Reflection photodiode, 31...Transmission photodiode, 32...Monitor photodiode, 33...Display unit, 34...Operation panel, 35...
...Digi spring for displaying number of times, 36...Digi spring for displaying reflectance, 37...Digi spring for displaying transparency, 38...Digi spring for displaying precision, 39...Average switch button, 4
0...Calibration switch button, 41...Ready lamp, 42...Sample lamp, 43...Light lamp.

Claims (3)

[Claims] (1) An optical fiber for light projection is interposed between the light source section and the measurement section, and the measurement section is equipped with a light receiving element electrically connected to the amplification section at one end for reflected light and transmitted light. In the rice grain whiteness measuring device, the other end of each optical fiber for each sample faces, is connected to the amplification section, and is provided with a calculation section and a display section. A rice grain polishing level measuring device characterized by being equipped with a vibrating device to keep it constant. (2) The above-mentioned vibrating device has a case holding frame into which the sample case is inserted, which is supported by a spring, and a protrusion protruding from the case holding frame is connected to the vibrator through a small gap. The rice grain polishing level measuring device according to item (1). (3) An optical fiber for projecting light is interposed between the light source section and the measuring section, and the measuring section is equipped with a light receiving element electrically connected to the amplifying section at one end for reflected light and transmitted light. In a rice grain whiteness measuring device, the other end of each optical fiber for light is exposed and connected to the amplification section and provided with a calculation section and a display section, the light source section includes a light receiving element electrically connected to the amplification section. A rice grain polishing level measuring device characterized by having one end of a monitoring optical fiber facing the other end.