JPH0143576B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic polishing level control device for a rice milling machine, and in particular measures the amount of reflected light and transmitted light from rice grains.
This device automatically controls the load of multiple friction rice mills based on the value of the polishing rate meter, and mills brown rice into rice-grade rice with a predetermined polishing degree.

Brown rice grains consist of a starch layer, or endosperm, which forms the core and a bran layer surrounding the outer periphery.The bran layer consists of an outer bran layer and an inner bran layer, and the outer bran layer consists of the outer pericarp and its inner wall surface. It consists of a seed coat, an inner bran layer, an ectosperm layer and an aleurone layer. The bran layer becomes thinner as the rice matures, and in mature rice it is so thin that it becomes good quality rice. As the fruit matures, the skin becomes thinner and the aleurone layer thickens. The powder from which the outer bran layer has been removed is called black bran, and the powder from which the inner bran layer has been removed is commonly called white bran. The outer bran layer is usually 42 to 48 microns, and the inner bran layer is 25 to 40 microns, and the degree of polishing is determined by the thickness of the aleurone layer in the inner bran layer, and the quality of polished rice is evaluated. Since the aleurone layer contains proteins and fats and oils that give flavor, the aleurone layer is an important component of white rice for rice, and white rice from which the aleurone layer has been completely removed is suitable for sake brewing. Not suitable for eating.

Conventionally, the whiteness of polished rice was measured only by the amount of reflected light and used as the degree of whitening, but this value is determined by the amount of diffusely reflected light from the rough surface generated on the surface of the grain of polished rice, and is not true. This value is completely unrelated to the degree of polishing. For example, the amount of reflected light from polished rice with bran attached immediately after polishing exhibits a much higher value of whiteness than the amount of reflected light from polished rice that has been thoroughly polished to remove the bran.
Since this value is the opposite of the progressing degree of whitening, it proves that the value is unrelated to the degree of whitening. In other words, whiteness is the amount of diffusely reflected light, and when the rice grain surface becomes glossy and dense, the amount of diffusely reflected light decreases due to the tendency of surface reflection. Conventionally, so-called whiteness meters, which measure the amount of reflected light relative to the amount of irradiated light, have been used in rice polishing machines to adjust the level of rice polishing.
The technology is disclosed in Japanese Patent Publication No. 54-24941. However, due to the problems mentioned above, the present applicant had previously filed Japanese Patent Application No. 56-128194 (Japanese Unexamined Patent Publication No.
58-30641), we invented a whiteness measuring device that detects the amount of transmitted light in addition to the amount of reflected light.
The true degree of polishing can be determined from the statistical curve value obtained by experimenting with three factors: the amount of light passing through the polished rice grains, the amount of diffusely reflected light on the surface of the polished rice, and the yield. Note that the amount of light transmitted through the polished rice grains changes depending on the grain density (volumetric weight), so by measuring the volumetric weight and density-correcting the amount of light, accurate whiteness can be measured. can do.

Next, since the degree of polishing depends on the load of the rice milling machine and the flow rate of rice, the milling degree meter is connected to the load control device of the rice milling machine, and the load is automatically controlled so that the rice is polished to a predetermined degree of polishing. This makes it possible to maintain and manage the polishing level of white rice at a constant level.

The load on the rice milling machine is the resistance to the rotational force of the milling trochanter, so it is the multiplicative product of the frictional force between the milling trochanter and the rice grains and the circumferential speed of the milling trochanter, and therefore the normal stress of friction, that is, the pressure. Adjusting either speed controls the load.

The pressure is regulated by the degree of compression of the outlet or the wall of the milling chamber, but when an external force is applied, there is a time lag before the milling trochanter responds to the rotational force, making it difficult to adjust the load instantaneously. Therefore, there is a drawback that hunting phenomenon occurs. On the other hand, if the rotation speed of the refined trochanter is adjusted, the adjustment will be responsive and sensitive load adjustment will be possible.

When adjusting the pressure, the characteristics of the whitening action are not significantly modulated, but if the load has wave characteristics, there is the inconvenience of incorrect adjustment due to hunting. In addition, when speed adjustment is used, the characteristics of the polishing action change greatly, but it is convenient to be able to quickly and accurately make stable adjustments even if the load has fluctuations.

In addition, the appropriateness of the rotation speed of the polishing trochanter is related to the milling action and the flow rate of rice, and in general, the grinding action of a grinding rice mill is proportional to the peripheral speed (circumference x rotation speed) of the grinding trochanter. However, if the rotation speed is too high, the rice grains will become spherical or the number of crushed grains will increase, and if the rotation speed is too low, the milling efficiency will be extremely reduced. The grinding speed of the white trochanter is about 1000 revolutions per minute. On the other hand, in friction type rice mills, the number of revolutions of the friction polishing trochanter is basically low, about 550 to 800 for blast type rice mills. Therefore, even if the number of revolutions is slightly increased or decreased, there is no problem caused by the increase or decrease of the number of revolutions in the grinding action described above. By changing the rotation speed of the friction polishing trochanter of the rice milling machine via the rotation speed variable device, we can maintain and control the polishing level of polished rice at a constant level and mass-produce high-quality polished rice with a high degree of polishing. We aim to develop and provide a device that achieves this goal.

The present invention will be explained with reference to embodiment figures. Fig. 1 is an overall view of the whiteness meter 1, and reference numeral 2 is an integrating sphere whose inner surface is a mirror, with one side open and a sample flow path 3.
However, the opposite side is also opened and a condensing lens 4 is provided, and the condensing lens 4 is provided with a light source lamp 5, a heat ray absorption filter 6, and a monochromatic light filter 7 in relation to each other. The absorption filter 6, the monochromatic light filter 7, and the condensing lens 4 form a light source device. 8 is the sample flow path 3
It is a marker pole equipped with a reference white board provided inside, and a flow path resistance increasing/reducing device (not shown) is provided at the bottom of the sample flow path 3 to appropriately adjust the sample density within the flow path. The optical axis of the light source device is tiltable and is configured to provide optimal transmitted light depending on the type and layer height of grains passing through the sample channel 3. Further, a transmitted light receiving element 9A serving as a transmitted light measuring device for capturing transmitted light from the sample is provided on the opposite side of the sample flow path 3 from the light source device, and is connected to the amplifier 10A. Further, a reflected light receiving element 9B serving as a reflected light measuring device for capturing reflected light from the sample is provided inside the integrating sphere 2 in a direction crossing a line connecting the light source device and the transmitted light receiving element 9A, and an amplifier 10B is provided.
Connect to. And both the amplifiers 10A, 10B
are connected to an arithmetic unit 12 consisting of an arithmetic element through analog-to-digital converters (hereinafter abbreviated as A-D converters) 11A and 11B, and the output side thereof is branched and one is connected to a precision indicator 13, The other end is connected to a comparison device 14, and the comparison device 14 is connected to a precision setting device 15, and
Its output side is connected to a regulating motor 17 via a rotational speed variable device 16. Note that 18 is a light incident shutter provided on the integrating sphere.

As the rotation speed variable device 16, an inverter device, an eddy current coupling device, etc. are used.
In this embodiment, a case will be described in which an inverter device is used.

In the above configuration, the calculated value of the arithmetic element provided in the arithmetic unit 12 is calculated based on the amount of reflection from the amplifier 10A and the amount of transmission from the amplifier 10B;
That is, the degree of fineness is expressed by the following formula.

Brightness=reflection amount+K・transmission amount, where K is a coefficient (using an experimentally determined value) for converting transmittance into whiteness.

Therefore, when sample grains flow into the sample flow path 3 and are adjusted to an appropriate density, the reflected light receiving element 9B and the transmitted light receiving element 9A receive a signal from the flow path resistance increase/decrease device. The reflectance and transmittance of the polished rice are measured, and the signals are sent to each amplifier 10.
A, 10B and A-D converter 11A, 11B
is input to the arithmetic device 12 via the arithmetic device 1
2, the calculated value is displayed on the whiteness indicator 13, and the signal is inputted to the comparator 14, and the desired value set on the whiteness setting device 15 is inputted to the whiteness setting device 15. The comparison signal of excess or deficiency is inputted to the inverter device of the rotation speed variable device 16 to increase or decrease the frequency of the alternating current to rotate the adjusting motor 17 at variable speeds.

Next, the friction type rice milling machine will be explained with reference to FIG. A supply port 22 and a discharge port 23 are provided in a polishing chamber 21 in which a friction type polishing trochanter 19 is mounted in a perforated whitening cylinder 20.
This is a friction-type rice polishing machine 29 in which a pulley 25 is attached to the rotating main shaft 24 and connected to the pulley 27 of an electric motor 26 by a belt 28. A load adjustment device 31 is provided to adjust the degree of compression of a compression lid 30 provided at the outlet 23 of the whitening chamber 21.

As shown in Fig. 3, there are multiple friction rice milling machines 36, 37,
A multiple rice milling device using No. 38 will be explained. The first grinding rice mill 35 and the second, third, and fourth friction rice mills 36, 37, and 38 are combined in series, and the fourth rice mill 38 is the final process.
A polishing degree meter 1A is installed at the discharge port of the machine, and each friction type rice polishing machine 36, 37, 38 is equipped with a rotation speed variable device 39, 4.
0 and 41, respectively, and the electric motors 42A, 42B, 42C and the whiteness meter 1.
Respectively and electrically connected to A.
Further, a separate electric motor 43 is connected to the grinding rice polishing machine 35. And the rotation speed variable device is
It is connected to a load distribution device that distributes the load to a plurality of friction-type rice mills (see Fig. 4), and the output side of the comparison device 14 provided in the polishing degree meter 1A is connected to the load distribution device 44 for each rotation speed. Variable devices 39, 40, 41
Each electric motor 42A,
42B and 42C, so if the difference between the fineness measured by the whiteness meter 1A and the set value is large, the load is distributed by the load distribution device 44, and the fourth machine 38 is connected to the third machine 38. No. 37, No. 3
By changing the frequency of alternating current in the order of 6, the rotation speed of each milling trochanter is adjusted step by step, and the load in each milling chamber is automatically adjusted quickly and efficiently.
It is possible to always maintain and control the polishing level of white rice at a constant level. If you adjust only the load of a specific friction rice mill, the adjustment range will be large and there is a risk of increasing broken rice, but since the load of multiple friction rice mills is adjusted, the ratio of load changes will be small, resulting in high polishing. It has remarkable effects such as mass production of high-quality polished rice can be achieved reliably, smoothly and quickly.

[Brief explanation of drawings]

The drawings are illustrations of embodiments of the present invention. Figure 1 is an explanatory diagram of the whiteness meter, Figure 2 is a side sectional view of a friction rice mill equipped with a whiteness meter, Figure 3 is a front view of the multiple rice milling device, and Figure 4 is the whiteness meter. FIG. 2 is a block diagram of a part of the electric circuit of FIG. 1, 1A... Whiteness meter, 2... Integrating sphere, 3... Sample channel, 4... Condensing lens, 5... Light source lamp, 6... Heat ray absorption filter, 7... Monochromatic light filter, 8... Signpost, 9A... Transmitted light Light receiving element, 9B... Reflected light receiving element, 10A, 10B... Amplifier, 11A, 11B...
Analog-to-digital converter, 12... Arithmetic device, 1
3...Fineness indicator, 14...Comparison device, 15...Fineness setting device, 16...Rotation speed variable device, 17...Adjustment motor, 18...Light incident shutter, 19...Friction whitening trochanter, 20...Porous wall whitening Tube, 21... Refining room, 22
... Supply port, 23 ... Discharge port, 24 ... Rotating main shaft, 25
... Pulley, 26... Electric motor, 27... Pulley, 28... Belt, 29... Friction rice mill, 30... Pressure lid, 31...
Load adjustment device, 32... Downflow gutter, 33... Sample discharge port, 34... Rotation speed variable device, 35... Grinding type rice polishing machine, 36, 37, 38... Friction type rice polishing machine, 39, 4
0, 41... Rotation speed variable device, 42A, 42B, 4
2C...Electric motor, 43...Electric motor, 44...Load distribution device.

Claims (1)

[Claims] 1 A whiteness meter that measures the degree of polishing by irradiating visible light from a light source onto the rice grains and detecting the amount of light reflected from the rice grains and the amount of light transmitted through the rice grains is used to measure polished rice in the final process of multiple friction-type rice mills. A load for changing the rotation speed of the plurality of friction rice mills according to a signal from the polishing rate meter, by providing a rotation speed variable device in the electric motor that is provided in the discharge flow path and rotating the polishing trochanter of the plurality of friction rice mills. A polishing degree control device for a rice milling machine, characterized by being equipped with a distribution device.