JP2015085209A - Rice milling method and rice milling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rice milling method and a rice milling machine which increase friction between rices, decrease friction between rice and an inner surface of a rice milling cage, thereby, enhance rice milling efficiency, shorten rice milling time and suppress temperature rise of rice after rice milling and the occurrence of crushed rice.SOLUTION: In a rice milling machine, rice of a specified amount is projected into a rice milling container, and a rice milling blade which is provided on a bottom part of the rice milling container and is rotated in the horizontal direction is rotated and driven and the projected rice is polished into a predetermined rice milling degree. Therein, the rice milling blade is intermittently rotated such that rice repeats convection and stoppage and performs rising and falling in the rice milling container during operation of rice milling. The rice milling blade is preferably configured such that a blade part is set as a rod shape having a small rotation resistance in order to minimize the crushed rice rate. Further, the rice milling container is preferably configured such that a lateral circumferential surface is set as a cylindrical shape.

Description

  The present invention relates to a rice milling method and a rice milling machine for milling brown rice to a predetermined degree of milling (spreading, white rice, and non-washed rice), and an object of the present invention is to suppress an increase in temperature due to the milling.

  As this type of rice milling machine, a convection-type rice milling machine shown in Patent Document 1 previously filed by the present applicant is known. This rice milling machine includes a metal netting machine rice mill into which rice (brown rice) is introduced, a rice bran container in which the milled rice basket is provided with a space, and a milled rice blade provided at the bottom of the milled rice basket, By rotating the milled rice blades, the brown rice is convected in the polished rice basket, and the straw layer of the brown rice is peeled off by friction between the rices or between the rice and the inner surface of the polished rice basket.

  In convection-type rice mills, the temperature rise of rice and the generation of broken rice are permanent issues. As the temperature of the rice rises, the moisture contained in the rice evaporates, resulting in overdried rice with a reduced moisture content in the rice. Over-dried rice having a moisture content of 14% or less cracks due to water immersion during cooking, and the starch of the rice flows out into the water as glue, so it becomes sticky and poor-tasting rice. The same is true for broken rice, and subdivided rice looks bad.

  Now, the temperature rise of rice and the occurrence of broken rice due to the polished rice are largely due to friction between the rice and the inner surface of the polished rice basket. This is probably because the friction between the rice and the inner surface of the polished rice basket has a greater impact on the rice than the friction between the rice. On the other hand, since the friction between rice is the contact of the same thing, the impact with respect to rice is small. In addition, the adsorptive power of the soot interacts to increase the peeling efficiency. In the rice milling machine of Patent Document 1, since the rice mill blades are controlled to be driven at a constant rotational speed during the rice milling, the force in the direction of rubbing the rice against the inner surface of the rice mill by the centrifugal force due to the rotation of the rice milling blades is large The squeezing pressure due to the friction between the rice was insufficient.

JP 2000-126625 A

  Therefore, the present invention increases the friction between the rice, reduces the friction between the rice and the inner surface of the polished rice basket, thereby improving the efficiency of rice polishing, shortening the time for rice polishing, and reducing the temperature rise and occurrence of broken rice after the rice polishing. The object is to provide a rice milling method and a rice milling machine.

  In order to solve such problems, a predetermined amount of rice is put into a rice milling container, and a horizontally rotating rice milling blade provided at the bottom of the rice milling container is driven to rotate, and the introduced rice is brought to a predetermined rice milling degree. In the rice milling machine, the rice milling blades are intermittently rotated so that the rice is repeatedly convected and stopped during the milling operation.

  In addition, a rice milling container into which a predetermined amount of rice is charged, a rice bran container in which the rice milling container is mounted inside, a rotary shaft attached vertically to the bottom of the rice milling container, a rice milling blade attached to and detached from the rotary shaft, In a rice mill equipped with a motor for rotating the shaft, the motor is intermittently operated for a predetermined time on-off for a predetermined time so that the rice is repeatedly convected and stopped in the rice milling vessel during the rice milling operation. A rotation control means for rotating intermittently is provided.

  In order to reduce the rate of crushed rice, the milled blades are composed of a boss part mounted on the rotation shaft of the milled rice container and a blade part extending from the boss part toward the inner surface of the milled rice container. It is desirable to use a rod shape. The rice milling container is preferably composed of a net-like material having a mesh smaller than that of rice grains or a punched punching plate, has a bottomed cylindrical shape with an open upper surface, and has a side peripheral surface having a cylindrical shape.

  According to the present invention, by intermittently rotating the rice milling blade during the rice milling operation, the convection and stop of the rice are repeated in the rice milling container, and the rice is rubbed against each other from various directions by the rice inflection. Thus, it is possible to relatively increase the friction between the rice after reducing the time for contacting the inner surface of the polished rice basket, and as a result, it is possible to shorten the time for polishing, increase the temperature, and reduce the occurrence of broken rice.

It is an external view of the rice milling machine of this invention. It is an internal sectional view of the rice mill. It is a composition exploded view of the rice mill. It is a block diagram which shows a control system. It is explanatory drawing which shows the rice mill data written in the memory. It is explanatory drawing which shows rice polishing operation | movement. It is explanatory drawing which shows the movement of the rice by intermittent rice polishing. It is explanatory drawing which shows test data. It is explanatory drawing which shows another example of the rice polishing data written in memory. It is explanatory drawing which shows another example of rice polishing operation | movement.

First, the structure of a rice mill will be described with reference to FIGS.
The rice milling machine main body 1 is formed by joining a resin-made body case 1a and a bottom plate 1b. The trunk case 1a includes a trunk section 2 that forms an outer shell of the main body 1, a bottomed cylindrical housing section 3 that is recessed from the upper surface of the trunk section 2 inward and downward, and a part of the upper surface is moved forward. The inclined portion 4 that is inclined is integrally formed. The container 3 accommodates the rice bran container 5, the polished rice basket 6, and the polished rice blades 7, and a lid 8 is attached to the upper surface. An operation panel 9 is provided on the surface of the inclined portion 4, and a control unit 10 is attached to the inside. The bottom plate 1b includes a base 11 and leg portions 12 fitted with rubber plates. A motor 13, a transmission member 14 such as a pulley belt, and a rotary shaft 15 are attached to the base 11.

Subsequently, each component will be described.
The accommodating portion 3 has a tapered shape in which the inner diameter becomes smaller as going downward, and is disposed on the base 11 in a state where the trunk case 1a and the bottom plate 1b are joined. A cylindrical part 16 to which the basket container 5 is attached is formed in the center of the bottom surface of the housing part 3 in a state where it bulges inward. The cylindrical portion 16 has a plurality of concavo-convex portions 17 for positioning and fixing the container 5 on the outer peripheral surface. A rotating shaft 15 attached to the base 11 passes through the center of the cylindrical portion 16, and a lower coupling 18 is attached to the tip of the rotating shaft 15.

  The basket container 5 has a similar shape to the housing part 3 and is attached with a gap from the inner surface of the housing part 3. At the center of the bottom surface of the jar container 5, an attachment cylindrical portion 19 that is externally fitted to the cylindrical portion 16 of the housing portion 3 is formed in a state where it bulges inward. The mounting cylindrical portion 19 forms a plurality of concave and convex portions 20 extending in and out of the peripheral surface, is fitted to the concave and convex portion 17 of the cylindrical portion 16 of the accommodating portion 3 on the inner concave and convex surface, and is polished on the outer concave and convex surface. Position and fix the car 6. In addition, a through hole 21 is opened on the upper surface of the mounting cylindrical portion 19, and the lower coupling 18 is exposed in a state where the container 5 is accommodated in the accommodating portion 3.

  The polished rice basket 6 has a shape in which a tapered surface is formed in the lower part and a cylindrical surface is formed in the upper part, and is formed from a metal mesh material having a mesh smaller than the rice grain or a punched punching plate. A disc-shaped bottom plate 22 is attached to the inner bottom surface of the polished rice basket 6, and an attachment cylinder portion 23 that is externally fitted to the attachment cylindrical portion 19 of the rice bran container 5 is attached to the outer bottom surface. The mounting cylinder portion 23 has a plurality of ribs 24 formed on the inner surface thereof, and is fitted to the concavo-convex portion 20 formed in the mounting cylindrical portion 19 of the basket container 5. A rotating shaft 25 passes through the center of the bottom plate 22 and the mounting cylinder portion 23, and an upper coupling 26 connected to the lower coupling 18 is attached to the lower end of the rotating shaft 25. Further, a carrying handle 27 is attached to the upper edge flange.

  The rice milling blade 7 is connected to a substantially cylindrical boss portion 28 and a lower side of the boss portion 28, extends horizontally along the inner bottom surface of the rice mill 6, and has its tip along the inner surface of the rice mill 6. It is composed of two blades 29 that are formed upright. A mounting hole 30 to be inserted into the rotating shaft 25 is opened in the boss portion 28. The attachment hole 30 is formed with a fitting portion 32 having a similar shape that fits with a polygonal stopper 31 formed on the outer peripheral surface of the rotary shaft 25.

  The lid 8 is made of a transparent material made of resin, and has a detachable handle 33 on the upper surface. Although not shown in particular, the convex portion formed on the outer peripheral edge of the lid 8 is attached by bayonet coupling that is fitted into the receiving convex portion formed on the inner edge of the opening of the housing portion 3.

  In this rice milling machine, the rice bran container 5 is accommodated in the accommodating part 3 of the main body 1, the rice milling basket 6 is accommodated in the rice bran container 5, and the rice milling blades 7 are attached to the rice milling basket 6. The lid body 8 is attached to and used. At this time, the bag container 5 is positioned and fixed in the accommodating portion 3 by fitting the concave and convex portion 20 of the mounting cylindrical portion 19 with the concave and convex portion 17 of the cylindrical portion 16. In addition, the polished rice basket 6 is positioned and fixed in the rice bran container 5 by fitting the ribs 24 of the mounting cylinder part 23 in accordance with the concavo-convex part 20 of the mounting cylinder part 19. Since a plurality of the concavo-convex portions are formed, alignment can be easily performed. When the polished rice basket 6 is accommodated in the rice bran container 5, the lower coupling 18 and the upper coupling 26 are joined, and the rotary shaft 15 on the main body 1 side and the rotary shaft 25 of the polished rice basket 6 are connected. As a result, the rotation of the motor 13 is transmitted to the rotary shaft 25 of the polished rice basket 6 via the transmission member 14, and the polished rice blades 7 attached to the rotary shaft 25 are rotated in the polished rice basket 6.

  In this rice milling machine, when a predetermined amount of brown rice is put in the rice mill 6 and the motor 13 is driven, the rice is convected by the rotation of the rice milling blades 7, and the surface of the rice is caused by friction between the rice and the friction between the rice and the inner surface of the rice mill The excess ridges are cut off. The peeled cocoon is discharged from the mesh of the polished rice basket 6 to the cocoon container 5 and stored in the cocoon container 5.

FIG. 4 is a block diagram showing the control system.
Next, the control system will be described.
The control unit 10 includes a microcomputer 35 and a motor drive circuit 36 that controls energization to the motor 13. The microcomputer 35 is connected to the operation panel 9 and includes a memory 37 in which a rice milling program and control data are written. The motor drive circuit 36 is connected to the motor 3 and is constituted by a switching circuit that interrupts energization of the motor 3 at a predetermined cycle.

  The motor 3 employs an AC brush motor that outputs high torque and high rotation speed. The operation panel 9 includes a degree selection key 38 for setting the degree of milling for processing brown rice such as sown rice, a rice quantity selection key 39 for setting the amount of rice to be processed, and a start / stop for stopping the operation. A stop key 40 and a non-washing rice key 41 for sharpening the white rice to make it non-washing rice are provided. Here, the degree selection key 38 can be used to select the degree of milling of “germ, 5 minutes, 7 minutes, white rice, no-wash rice”, and the rice quantity selection key 39 can select the amount of rice from 1 to 5 It has become.

  In the memory 37, motor drive data as shown in FIG. 5 is written. This motor drive data consists of the operation time t of the motor 13, the energization rate n when the motor 13 is driven, and the target rotational speed r of the motor 13, and the degree of rice polishing (germ, 5 minutes, 7 minutes, white rice)・ Non-washed rice) is stored for each rice quantity (1 to 5 go). In the operation time data, a time until reaching a predetermined degree of rice polishing is allocated in a range from the start of rice polishing to the end of rice polishing. The energization rate data is set as a motor energization rate for setting the motor 13 to the specified rotational speed r in the allocated operation time. For example, in the “white rice” course data in FIG. 5, the operation time is allocated to t1 to t4 corresponding to the degree of rice polishing, and the energization rate for maintaining the rotation speed rb defined during each operation time is shown. n1 to n4 are set.

  Here, the degree of rice milling refers to the progress of milling. The rotational load at the time of rice milling varies depending on the degree of rice milling, and is larger when it is closer to brown rice and smaller when it is closer to white rice. In order to maintain the prescribed rotational speed without being affected by the degree of dewetting, the progress state of the dehulling is predicted from the operation time, and the motor 13 is driven at an energization rate according to the progressing state of the dehulling.

  In addition, the numerical value of the number of rotations is obtained by each test. In the embryo course, the number of rotations ra is set to 1630 rpm ± 100 rpm, and in the case of 5 minutes / 7 minutes rice / white rice course, the number of rotations rb is 2100 rpm. It is desirable to set the rotational speed rc to 1800 rpm ± 100 rpm for the washing-free rice course.

  In each operation time t0 to t5, the motor 13 is driven by intermittent operation as shown in FIG. This intermittent operation is carried out in order for the rice to repeatedly lift and convection and stop in the rice mill 6 by the rotation of the rice milling blades 7. In this example, the motor 13 is operated regardless of the amount of rice and the degree of rice milling. 5 seconds drive-realized by stopping 0.5 seconds. Further, the energization rate n of the motor 13 is controlled by a method in which the motor energization ratio is varied depending on how many cycles are energized while the AC frequency is divided into a predetermined number (for example, 16 cycles).

  For example, in the energization rate n1 during the operation time t1 in FIG. 6, since the rotational load due to brown rice is large, the motor is energized in 14 of 16 cycles and the motor is de-energized in 2 cycles in order to maintain the rotation speed rb. To do. Further, the energization rate n2 during the operation time t2 is determined that the removal has progressed to some extent, and in order to maintain the rotational speed rb, the motor is energized in 12 of the 16 cycles, and the motor is de-energized in 4 cycles. To do. Thereby, the motor 13 is always rotated at the rotation speed rb, and a stable rotation operation is given.

Hereinafter, the rice milling operation in this rice mill will be described.
Each member of the rice milling machine is attached in the above-described procedure, brown rice to be polished is put into the rice mill 6, the degree of milling is selected with the degree selection key 38, and the rice quantity is selected with the rice quantity selection key 39. From this state, when the start / stop key 40 is pressed, rice milling is started.

  When the degree of milling “white rice” and the amount of rice “5 go” are selected, the data of “white rice” and “5 go” is read from the motor drive data of FIG. 5, and the motor 13 is controlled along this data. That is, as shown in FIG. 6, first, the motor 13 is intermittently operated at 5 seconds On-0.5 seconds Off until the time t1 elapses, and the motor 13 is rotated at an energization rate of n1 for 5 seconds. Control is performed to keep the number in rb. Similarly, while the time t2, t3, t4 elapses, the motor 13 is intermittently operated at 5 seconds On-0.5 seconds Off, and the energization rate is rotated as n2, n3, n4, respectively, for 5 seconds when the motor 13 is driven. Control to hold the number rb. When the milling time t1 to t4 elapses, the motor 13 is stopped and the milling is finished. After the milling is finished, the rice bran container 5 is removed from the container 3 and then the rice basket 6 is removed from the rice bran container 5 so that the rice remains in the rice mill 6 and the rice bran 5 remains. can do.

  Now, when the motor 13 is driven, the rice in the polished rice basket 6 is convected as indicated by the solid arrow line in FIG. That is, the rice in the polished rice basket 6 is pushed outward by the centrifugal force of the blade 29 of the polished rice blade 7 toward the inner surface of the polished rice basket 6 [a] and rises along the inner surface of the polished rice basket 6 [b]. Convection so that it flows down from the center of the basket 6 along the boss 28 of the rice milling blade 7 [c]. Due to this convection, as shown by the dotted line in FIG. 7 (a), the rice moves so as to be higher on the inner surface side of the polished rice basket and lower on the center side, and the brown rice is caused by friction between the rice grains and the inner surface of the polished rice basket. It is stripped.

  Further, when the motor 13 is stopped, the convection due to the rice milling blades 7 is reduced, and the movement toward the inner surface of the polished rice basket 6 and the movement rising along the inner surface of the polished rice basket are weakened, as shown by the dotted line in FIG. , Rice settles by gravity. Due to the inertia of the sedimentation and convection, scouring pressure is applied to the rice grains from various directions, and the deaggregation due to friction between the rice grains is promoted.

  In this way, by intermittently operating the motor 13, the rice repeats uplifting in the polished rice basket 6 due to the convection action when the milled rice blade 7 rotates and the settling action when the milled rice blade 7 stops. . Rice inflection has the effect of reducing the milling time due to friction with the inner surface of the milled rice and increasing the milling time due to friction between the rice grains. As a result, the rice milling time is shortened and the temperature rise of the rice is suppressed.

  FIG. 8 is a diagram comparing rice milling by continuous operation and rice milling by intermittent operation. This test was conducted in the same environment (equipment, outside temperature, humidity, etc.), and compared rice milling time, temperature rise, and broken rice rate when brown rice 5 rice was polished to white rice (milling degree 90% or more). It is.

  As shown in Sample A in FIG. 8, in continuous rice polishing, a degree of rice polishing of 90.3% was obtained in 5 minutes of rice polishing, the temperature rise of rice was 21.8 ° C., and the rate of broken rice was 18.4%. On the other hand, in the case of intermittent rice polishing, a rice polishing degree of 90.5% was obtained in 3 minutes and 20 seconds of rice polishing, the temperature rise of the rice was 16.0 ° C., and the rate of broken rice was 20.9%. From this result, it was confirmed that intermittent milling could shorten the milling time and suppress the temperature rise of the rice.

  On the other hand, the rate of broken rice is inferior to intermittent milled rice. This is presumed that many rice cracks occur due to the impact when the milled rice blades 7 are stopped and then restarted. Therefore, the shape of the rice milling blades 7 was changed to one with reduced resistance during rotation. As shown in Sample B of FIG. 8, this rice milling blade 7 'is constructed by attaching a pair of left and right rod-shaped blades extending horizontally along the inner bottom surface of the milled rice basket 6 below the substantially cylindrical boss portion. Has been. When the above-mentioned test was carried out using this rice milling blade 7 ', the rice milling degree of 91.0% was obtained with intermittent milling in 2 minutes 50 seconds, the temperature rise of the rice was 15.0 ° C, the rate of breaking rice It was 14.6%. From this result, it was confirmed that intermittent milling and the milling blade 7 'of a rod-shaped blade can shorten the milling time, suppress the temperature rise of the rice, and lower the rate of crushed rice.

  We also examined the shape of the polished rice basket, which affects broken rice. The shape of the polished rice basket has been changed to one with reduced resistance during rotation. As shown in Sample C of FIG. 8, the polished rice basket 6 'has a cylindrical shape having a substantially the same inner diameter and has a mesh smaller than that of the rice grain or punched punching. It is formed from a plate. When the above-mentioned test was carried out using the polished rice basket 6 ′ and the polished rice blade 7 ′ of Sample B, the rice milling rate of 91.0% was obtained in 3 minutes and 20 seconds by intermittent milling, and the temperature of the rice increased. Became 19.7 degreeC and the broken rice rate became 11.6%. From this result, it was confirmed that the milled rice, the milled rice blade 7 'of the rod-shaped blade, and the milled rice basket 6' of the cylindrical drum shortened the milling time, suppressed the temperature rise of the rice, and lowered the rate of crushed rice.

  According to such verification, interrupted rice is effective in shortening the rice polishing time and suppressing the rise in temperature of the rice. It has been confirmed that it effectively acts on the decrease in the temperature.

  Based on the above verification, the present invention intermittently drives the motor during milling to shorten the milling time and suppress the temperature rise of the rice. Therefore, the above-described configuration is merely an example for carrying out the present invention, and is not particularly limited. For example, in the rule embodiment, the material of the polished rice basket is a metal mesh or punched punching plate, but it may be made of resin, and if it is not necessary to discharge the koji into the koji container, It is possible to carry out the rice milling without using a net-like material or a punching plate.

  Moreover, in the said embodiment, although the rice-milling time is allocated according to the degree of rice-milling progress, and the energization rate for maintaining a predetermined rotation speed in the allocated time is set, it is always the same during the rice-milling time. You may make it control by an electricity supply rate. That is, as shown in FIG. 9 and FIG. 10, if the degree of milling is “white rice” and the amount of rice is “5 go”, considering that the rotational speed increases with the degree of rice milling, By setting the energization rate n3 at which the rotational speed rb (= 2100 rpm) is set in the middle stage, the rotational speed can be in the range of 2100 rpm ± 100 rpm, and the control can be simplified.

  Further, in the above embodiment, the variable method of the energization ratio of the motor for controlling the energization rate is realized by the thinning control with the energization number in 16 cycles. However, as shown in FIG. You may carry out by the phase control which turns off a phase angle. In this case, the generation of load and noise on the motor is suppressed.

DESCRIPTION OF SYMBOLS 1 Rice mill main body 3 Storage part 5 Rice bran 6 Rice milling basket 7 Rice milling blade 10 Control part 35 Microcomputer 36 Motor drive circuit 37 Memory

Claims (4)

Rice milling operation is performed in a rice mill that puts a specified amount of rice into a rice milling vessel and rotationally drives a horizontally rotating rice milling blade provided at the bottom of the rice milling vessel to refine the introduced rice to a predetermined degree of rice milling. A rice milling method comprising intermittently rotating the rice milling blades so that the rice is repeatedly convected and stopped in the rice milling container.
A rice mill container into which a predetermined amount of rice is charged, a rice bran container in which the rice mill container is mounted inside, a rotary shaft that is vertically attached to the bottom of the rice mill container, a rice mill blade that is attached to and detached from the rotary shaft, and a rotary shaft In the rice milling machine equipped with a motor that rotationally drives
Rotation control means for intermittently rotating the rice milling blades by intermittently operating the motor for a predetermined time on-predetermined time off so that the rice is repeatedly convected and stopped during the milling operation This is a rice milling machine.
The rice milling blade is composed of a boss part mounted on the rotating shaft of the rice milling container and a blade part extending from the boss part toward the inner surface of the rice milling container, and the blade part has a rod-like shape with little rotational resistance. The rice mill according to claim 2, characterized in that it is characterized in that
The rice milling container is composed of a net-like material having a mesh smaller than rice grains or a punched punching plate, has a bottomed cylindrical shape with an open top surface, and has a side peripheral surface of a cylindrical shape. The rice mill according to claim 2 or 3.

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