JP7836374B2 - Rice pre-treatment method and rice pre-treatment system - Google Patents

Description

This invention relates to a method and system for pre-processing rice for cooking, particularly in situations where relatively large quantities of rice are required, such as in school and hospital meals, and in the large-scale food industry.

When washing and cooking relatively large quantities of rice, a pre-processing system is often used in which the washed polished rice grains are stored in a soaking tank filled with soaking water, allowing them to absorb the water and become soaked rice grains.

Patent Document 1 describes a rice washing apparatus in which polished rice grains are flowed through a rice washing means installed in a pipe along with rice supply water to become pre-washed rice grains. The mixed fluid of rice supply water and pre-washed rice grains is then supplied to an inclined plate made of a mesh net to separate the pre-washed rice grains from the mixed fluid. The separated pre-washed rice grains are then allowed to flow into an immersion tank containing immersion water, thereby immersing the pre-washed rice grains in the immersion water.

Japanese Patent Publication No. 2015-37776

However, in the rice washing apparatus described in Patent Document 1, the pre-washed rice grains separated from the mixed fluid are coated with the water used to deliver the rice, which contains rice bran that has been detached from the polished rice grains during the washing process. These pre-washed rice grains, still coated with the water containing rice bran, then fall and flow into the immersion water stored in the immersion tank.

When a large quantity of pre-washed rice grains are sent to the immersion tank, the rice grains, still coated with water containing rice bran, fall and flow into the tank, generating a large amount of rice bran foam on the surface of the water stored in the tank. The immersion tank is designed to discharge the overflow water along with the rice bran foam floating on the surface. However, this only discharges the foam near the overflow pipe; it does not actively discharge the foam floating on the surface. Therefore, the generated rice bran foam spreads across the water surface, adheres to the tank walls, and dries, making it difficult to keep the equipment clean.

This invention aims to solve the aforementioned conventional problems by providing a rice pre-treatment method and system that allows for the hygienic use of the immersion tank by reducing the amount of rice bran adhering to the tank.

The rice pre-treatment method of the present invention is:
Polished rice grains are washed to become pre-washed rice grains.
The process includes a soaking step in which the pre-washed rice grains are dropped and flowed into a soaking tank containing soaking water, and the pre-washed rice grains are soaked in the soaking water to become soaked rice grains.
In the aforementioned immersion step,
The opening of the flow pipe, which extends in a substantially vertical direction, is positioned below the water level of the immersion water to form the water level of the immersion water within the flow pipe.
The method is characterized by causing the pre-washed rice grains, which have been allowed to fall and flow through the flow pipe, to land on the surface of the soaking water formed inside the flow pipe.

Furthermore, the rice pre-treatment method of the present invention is
Polished rice grains are washed to become pre-washed rice grains.
The process includes a soaking step in which the pre-washed rice grains are dropped and flowed into a soaking tank containing soaking water, and the pre-washed rice grains are soaked in the soaking water to become soaked rice grains.
In the aforementioned immersion step,
The present invention is characterized by allowing the washed rice grains, which have been allowed to fall and flow, to land on the surface of the soaking water within a partitioned area, which is a region defined by the inner wall of the soaking tank and a plate-shaped partitioning member.

The rice pre-processing system of the present invention is
A soaking tank that stores a predetermined amount of soaking water and soaks pre-washed rice grains, which are polished rice grains that have been washed, in the soaking water to make soaked rice grains,
A flow pipe extending in a substantially vertical direction, which causes the washed rice grains to fall and flow into the soaking water,
Equipped with,
The opening of the flow pipe is positioned below the water level of the immersion water to form the water level of the immersion water inside the flow pipe.
The method is characterized by causing the pre-washed rice grains, which have been allowed to fall and flow through the flow pipe, to land on the surface of the soaking water formed inside the flow pipe.

The rice pre-processing system of the present invention is
A soaking tank stores a predetermined amount of soaking water, and soaks pre-washed rice grains, which are polished rice grains that have been washed, in the soaking water to make soaked rice grains,
A plate-shaped partitioning member that partitions the rice bran foam floating on the surface of the immersion water,
Equipped with,
A partitioned area is formed on the surface of the immersion water, which is a region partitioned by the inside of the wall surface of the immersion tank and the partitioning member.
The method is characterized by causing the pre-washed rice grains, which have been allowed to fall and flow, to land on the surface of the soaking water within the designated area.

According to the rice pre-treatment method and rice pre-treatment system of the present invention, the amount of rice bran adhering to the immersion tank can be reduced, allowing the immersion tank to be used cleanly.

A block diagram showing the overall configuration of a rice pre-processing system according to one embodiment of the present invention. A block diagram showing the configuration of the rice washing section of the pre-processing system for rice cooking described above. Front cross-sectional view showing the configuration of the main components of the separation section of the rice pre-processing system described above (hatching omitted). This is an external view showing the configuration of the separator in the rice pre-processing system described above, where (a) is a top view, (b) is a front view, and (c) is a front end view along line A-A in (a) (hatching omitted). The above diagram shows the configuration of the main components of the immersion section of the rice cooking pre-treatment system, and is a top cross-sectional view (hatching omitted) showing the state when the immersion tank is filled with immersion water up to the full water level. The image shows a top cross-sectional view (hatching and omitting of rice grains) illustrating the flow state of the soaking water when it is filled to the maximum level in the soaking tank of the above rice pre-processing system and a predetermined amount of soaked rice grains are stored. Cross-sectional view along line B-B in Figure 5 (hatching omitted). Cross-sectional view along line D-D in Figure 6 (hatching omitted) (soaked rice grains are represented only by their edges). This is a cross-sectional view (hatching omitted) along line B-B in Figure 5, showing the state in which the guide board is being pulled upward by pulling the chain upward. A perspective view showing the configuration of the fixed compartment member and the movable compartment member of the immersion section of the rice cooking pre-treatment system described above, wherein (a) shows the state with only the fixed compartment member and (b) shows the state with the movable compartment member attached to the fixed compartment member. This is a cross-sectional view (hatching omitted) along the line C-C in Figure 5, showing that pre-washed rice grains are falling and flowing into the immersion tank, but the movable compartment member is still closed. This is a cross-sectional view (hatching omitted) along the line E-E in Figure 6, showing a state where a predetermined amount of pre-washed rice grains are stored and the movable compartment member is open by a predetermined angle. This is a cross-sectional view (hatching omitted) along the line E-E in Figure 6, showing the state in which soaked rice grains stored in the soaking tank flow through the piping to the rice distribution section. A block diagram showing the configuration of the main components of the rice distribution and water supply sections of the pre-processing system for rice cooking described above. A block diagram showing the configuration of the main components of the purification section of the rice cooking pre-treatment system described above. A step diagram showing the operation of the rice pre-processing system described above.

The first invention is,
Polished rice grains are washed to become pre-washed rice grains.
The process includes a soaking step in which the pre-washed rice grains are dropped and flowed into a soaking tank containing soaking water, and the pre-washed rice grains are soaked in the soaking water to become soaked rice grains.
In the aforementioned immersion step,
The opening of the flow pipe, which extends in a substantially vertical direction, is positioned below the water level of the immersion water to form the water level of the immersion water within the flow pipe.
This method is a pre-treatment method for cooking rice, characterized by causing the pre-washed rice grains, which have been allowed to fall and flow through the flow pipe, to land on the surface of the soaking water formed inside the flow pipe.

This configuration, compared to positioning the opening of the flow pipe above the water surface, limits the water surface into which the pre-washed rice grains land to the water surface within the flow pipe, thereby reducing the amount of rice bran foam generated when the pre-washed rice grains land in the soaking water. Furthermore, it suppresses the adhesion of rice bran to the walls of the soaking tank, allowing for cleaner use of the tank.

The second invention is, in the first invention,
In the immersion step,
This method of pre-treating rice for cooking is characterized by allowing washed rice grains, which have been allowed to fall and flow through a fluid pipe, to land on the surface of the soaking water formed inside the fluid pipe within a partitioned area, which is an area defined by the inside of the wall of the soaking tank and a plate-shaped partition member.

This allows the rice bran foam generated when pre-washed rice grains come into contact with the soaking water to be retained within the designated area.

The third invention is,
Polished rice grains are washed to become pre-washed rice grains.
The process includes a soaking step in which the pre-washed rice grains are dropped and flowed into a soaking tank containing soaking water, and the pre-washed rice grains are soaked in the soaking water to become soaked rice grains.
In the aforementioned immersion step,
This method of pre-treating rice for cooking is characterized by allowing the washed rice grains, which have been allowed to fall and flow, to land on the surface of the soaking water within a partitioned area, which is a region defined by the inside of the wall of the soaking tank and a plate-shaped partitioning member.

This allows the rice bran foam generated when pre-washed rice grains come into contact with the soaking water to be contained within the designated area. Furthermore, it prevents rice bran from adhering to the walls of the soaking tank, allowing for clean use of the tank.

The fourth invention is, in the third invention,
In the immersion step,
The opening of the flow pipe, which extends in a substantially vertical direction, is positioned below the water level of the immersion water to form the water level of the immersion water within the flow pipe.
This method is a pre-treatment method for rice cooking characterized by allowing pre-washed rice grains, which have been allowed to fall and flow through the fluidized pipe within a designated area, to land on the surface of the soaking water formed inside the fluidized pipe.

This allows the water surface into which the pre-washed rice grains land to be limited to the water surface inside the flow pipe, compared to when the opening of the flow pipe is positioned above the water surface. This reduces the amount of rice bran foam generated when the pre-washed rice grains land in the soaking water.

The fifth invention is based on any one of the first to fourth inventions,
By repeatedly changing the direction of flow of pre-washed rice grains that have been washed, the kinetic energy of the pre-washed rice grains as they flow is reduced.
This method is a pre-treatment method for cooking rice, characterized by immersing pre-washed rice grains, whose kinetic energy has been reduced, in soaking water.
This reduces the impact on the washed rice grains when they hit the surface of the soaking water, compared to when the kinetic energy is not reduced, and also reduces the amount of rice bran foam generated on the surface of the soaking water stored in the soaking tank.

The sixth invention is,
A soaking tank that stores a predetermined amount of soaking water and soaks pre-washed rice grains, which are polished rice grains that have been washed, in the soaking water to make soaked rice grains,
A flow pipe extending in a substantially vertical direction, which causes the washed rice grains to fall and flow into the soaking water,
Equipped with,
The opening of the flow pipe is positioned below the water level of the immersion water to form the water level of the immersion water inside the flow pipe.
This pre-treatment system for rice cooking is characterized by causing the pre-washed rice grains, which have been allowed to fall and flow through the flow pipe, to land on the surface of the soaking water formed inside the flow pipe.

This configuration, compared to positioning the opening of the flow pipe above the water surface, limits the water surface into which the pre-washed rice grains land to the water surface within the flow pipe, thereby reducing the amount of rice bran foam generated when the pre-washed rice grains land in the soaking water. Furthermore, it suppresses the adhesion of rice bran to the walls of the soaking tank, allowing for cleaner use of the tank.

The seventh invention is, in the sixth invention,
It further includes a plate-shaped partitioning member that divides the rice bran foam floating on the surface of the soaking water,
A partitioned area is formed on the surface of the immersion water, which is a region partitioned by the inside of the wall of the immersion tank and the partitioning member.
This pre-treatment system for rice cooking is characterized by allowing pre-washed rice grains, which have been allowed to fall and flow through a fluid pipe within the aforementioned compartment, to land on the surface of the soaking water formed inside the fluid pipe.

This allows the rice bran foam generated when pre-washed rice grains come into contact with the soaking water to be retained within the designated area.

The eighth invention is,
A soaking tank that stores a predetermined amount of soaking water and soaks pre-washed rice grains, which are polished rice grains that have been washed, in the soaking water to make soaked rice grains,
A plate-shaped partitioning member that partitions the rice bran foam floating on the surface of the immersion water,
Equipped with,
A partitioned area is formed on the surface of the immersion water, which is a region partitioned by the inside of the wall surface of the immersion tank and the partitioning member.
This pre-treatment system for rice cooking is characterized by dropping and flowing the pre-washed rice grains onto the surface of the soaking water within the designated area.

This allows the rice bran foam generated when pre-washed rice grains come into contact with the soaking water to be contained within the designated area. Furthermore, it prevents rice bran from adhering to the walls of the soaking tank, allowing for clean use of the tank.

The ninth invention is, in the eighth invention,
It further includes a flow pipe that extends in a nearly vertical direction and causes the washed rice grains to fall and flow into the soaking water,
The opening of the flow pipe is positioned below the water level of the immersion water to form the water level of the immersion water inside the flow pipe.
This pre-treatment system for rice cooking is characterized by allowing the pre-washed rice grains, which have been allowed to fall and flow through the fluidized pipe within a designated area, to land on the surface of the soaking water formed inside the fluidized pipe.

This allows the water surface into which the pre-washed rice grains land to be limited to the water surface inside the flow pipe, compared to when the opening of the flow pipe is positioned above the water surface. This reduces the amount of rice bran foam generated when the pre-washed rice grains land in the soaking water.

The tenth invention is based on any one of the seventh to nineth inventions,
This rice pre-treatment system is characterized in that, when the mass of the soaked rice grains located on the ridges of the soaked rice grains stored in the soaking tank is applied to the partition member, at least a part of the partition member rotates toward the outside of the soaking tank.
This allows more rice grains to be stored in the soaking tank, even if the lower end of the partition member is in contact with the ridge line of the soaked rice grains stored in the soaking tank.

(Embodiment 1)
(Overview of the rice cooking pre-processing system)
The following describes a rice pre-treatment method and a rice pre-treatment system 10, which are embodiments of one embodiment of the present invention.

First, the basic configuration of the rice cooking pre-treatment system 10 of the present invention will be explained.
As shown in Figure 1, the rice pre-processing system 10 is broadly composed of the following components.
(1) The rice washing unit 20 mixes air, water W2 for supplying rice, and polished rice grains (rice grains) R1 to form a mixed fluid, and then flows this mixed fluid within the rice washing means 32 to wash the polished rice grains R1 and supply the rice.
(2) Separation unit 40 separates the mixed fluid that has been mixed, washed, and delivered in the rice washing unit 20 into the delivered water W3 containing air and the pre-washed rice grains (rice grains) R2.
(3) The immersion section 60 stores the pre-washed rice grains R2 separated by the separation section 40 while immersing them in the immersion water W4 stored in the immersion tank 61, and overflows the immersion water W4 stored in the immersion tank 61.
(4) The rice distribution unit 90 distributes a predetermined amount of soaked rice grains (rice grains) R3, which have been soaked in the soaking unit 60, to the rice cooker pot 97.
(5) Water supply unit 100 that supplies cooking water W6 at a predetermined temperature to the rice cooker pot 97 into which soaked rice grains R3 have been supplied.
(6) A purification unit 120 purifies the air-containing rice supply water W5, which is mixed with soaking water, so that it can be used again in the rice washing unit 20 to wash polished rice grains R1.
(7) Control unit 140 which is electrically connected to the equipment of each part and performs centralized control.

Furthermore, the rice grains obtained by milling brown rice are referred to as "polished rice grains (rice grains) R1," the polished rice grains R1 washed in the washing section 20 with air-infused rice water W3 are referred to as "pre-washed rice grains (rice grains) R2," and the pre-washed rice grains R2 soaked in the soaking section 60 with soaking water W4 are referred to as "soaked rice grains (rice grains) R3."

Furthermore, the water supplied to the rice from the purification unit 120 and flowing to the ejector 26 of the rice washing unit 20 is referred to as "supplied rice water W2," the water used for supplying and washing the polished rice grains R1 after mixing air and supplied rice water W2 in the rice washing unit 20 is referred to as "supplied rice water containing air W3," the water stored in the immersion tank 61 is referred to as "immersion water W4," and the water supplied to the rice cooker 97 is referred to as "cooking water W6." Also, while the clean water W1 refers to tap water, for example, pure water or soft water, or other types of water, may be used.

The term "piping" may refer to either metal pipes, such as stainless steel, or resin pipes, such as polyvinyl chloride. However, considering the ease of cleaning the inside of the pipes, it is preferable to use resin pipes, which are easier to attach and detach than metal pipes.

Furthermore, the term "valve" may refer to an electromagnetic valve or electric valve controllable by the control panel 141 located in the control unit 140. Manual adjustments or electrical control may be unnecessary in certain locations where they are not required; in such cases, a manual valve may be used. However, to prevent operator errors when operating the rice pre-processing system 10, it is preferable to use an electromagnetic valve or electric valve that can be controlled by a program on the control panel 141, as well as one that can be controlled independently.

Note that in Figures 2, 14, and 15, some areas are indicated by dashed lines. These dashed lines indicate areas not included in the rice washing section 20, rice distribution section 90, water supply section 100, and purification section 120 shown in Figures 2, 14, and 15, respectively.

(1) Rice washing section Next, the configuration of the rice washing section 20 will be explained.

The rice washing section 20 shown in Figure 2 mixes air, clean water W1, and polished rice grains R1 using an ejector 26. This mixed fluid M1 of air-containing water and polished rice grains is then flowed through the rice washing means 32 to wash the polished rice grains R1, before being sent to the separation section 40 for the next step.

The rice washing section 20 is
An introduction guide 21 guides the supplied polished rice grains R1 and prevents them from scattering to the outside,
A hopper-shaped receiving cylinder 22 receives the polished rice grains R1 that are guided and fall by the introduction guide 21,
Multiple clean water nozzles 25 are used to spray clean water W1 supplied through the piping 23 into the inside of the wall of the receiving cylinder 22 by opening the valve 24, causing the polished rice grains R1 to flow down along the inside of the wall of the receiving cylinder 22.
A pump 29 draws in the rice-supplied water W2 stored in the second purification tank 128 of the purification unit 120 (described later) via a filter 134, discharges it, and discharges it through the piping 28 to the ejector 26 to cause it to flow.
A valve 30 adjusts the flow rate of the rice water W2 discharged from the pump 29 and flowing to the ejector 26,
The ejector 26 draws in air from the receiving cylinder 22 and polished rice grains R1 that are flowing down the inside of the wall surface of the receiving cylinder 22 together with clean water W1 through the suction port 27, mixes the air, clean water W1 and polished rice grains R1 with the rice supply water W2 that is discharged and flowing through the piping 28 by the pump 29, and discharges the mixture fluid M1 of the rice supply water containing air and polished rice grains.
A rice supply pipe (piping) 31 sends the mixed fluid M1 of rice supply water containing air and polished rice grains, which is discharged from the ejector 26 and flows, to the separation unit 40 which performs the next process.
A rice washing means 32 is incorporated into the middle of the rice supply pipe 31 and washes the polished rice grains R1 by flowing a mixed fluid M1 of rice supply water containing air and polished rice grains inside the pipe.
It is equipped with.

The cylindrical introduction guide 21 is connected to a hopper-shaped receiving cylinder 22, which has a roughly triangular shape with its apex at the bottom when viewed in front. Because the introduction guide 21 is cylindrical with openings at both the top and bottom, polished rice grains R1 can be supplied to the receiving cylinder 22 from above the introduction guide 21 without scattering.

Multiple clean water nozzles 25 are attached to the inside of the slanted wall surface of the receiving cylinder 22, which connects through the lower opening (not indicated by a symbol) of the installation guide 21. These multiple clean water nozzles 25 are connected via piping 23 to, for example, a water tap or other device that supplies tap water.

A valve 24 is installed in the piping 23 so that, when opened, it can supply clean water W1, such as tap water. By opening the valve 24, clean water W1 is sprayed downwards from multiple clean water nozzles 25 along the inside of the slanted wall surface of the receiving cylinder 22.

The opening (not indicated by a reference numeral) at the downward-facing apex of the receiving cylinder 22 in a front cross-sectional view is connected to the suction port 27 of the ejector 26. Furthermore, a pipe 28 is connected to the upstream side of the ejector 26. This pipe draws in the rice-supplied water W2 stored in the second purification tank 128 of the purification unit 120 (described later) via a filter 134, is pumped in by a pump 29, and discharged to the ejector 26.

A valve 30 is attached to the discharge side of the pump 29 in the piping 28. By adjusting the opening of the valve 30, the flow rate per unit time of the rice supply water W2 discharged by the pump 29 and flowing into the ejector 26 is adjusted. A rice supply pipe 31 is connected downstream of the ejector 26 to carry a mixed fluid M1 of rice supply water containing air and polished rice grains, which will be described later.

A rice delivery pipe 31 connected to the ejector 26 is equipped with a rice washing means 32 that washes the polished rice grains R1 by circulating a mixed fluid M1 of air-containing rice delivery water and polished rice grains inside the pipe. The rice washing means 32 is a component capable of statically agitating the fluid flowing inside, such as a static mixer.

The rice delivery pipe 31, which incorporates a rice washing mechanism 32, is connected to the separation section 40 that performs the next step. A mixed fluid M2 of air-containing rice delivery water and pre-washed rice grains flows through the rice delivery pipe 31 downstream of the rice washing mechanism 32.

(2) Separation section Next, the configuration of the separation section 40 will be described.

The separation unit 40 shown in Figure 3 separates the mixed fluid M2 of air-containing rice water and pre-washed rice grains flowing from the rice washing unit 20 into air-containing rice water W3 and pre-washed rice grains R2 using a separator 43, and then allows the pre-washed rice grains R2 to flow down into the immersion unit 60 for the next process.

The separation unit 40 is
A circular plate-shaped lid 41, which is attached to the first water receiving section 44 so as to extend radially around the opening 31a of the rice supply pipe 31 through which a mixed fluid M2 of air-containing rice supply water and pre-washed rice grains flows from the rice washing section 20, is provided.
A diffuser 42, which is attached to the lid 41 so as to be located below the opening 31a of the rice supply pipe 31, is a downward-spreading cone-shaped diffuser 42 that causes the mixed fluid M2 of air-containing rice supply water and pre-washed rice grains, which flows in a substantially horizontal direction from the opening 31a of the rice supply pipe 31 in a substantially vertical direction,
A cylindrical separator 43 separates the mixed fluid M2 of air-containing rice water and pre-washed rice grains, which has been flowed in a nearly horizontal direction by the diffuser 42, into air-containing rice water W3 and pre-washed rice grains R2.
The lid 41 is placed over the top to create a near-sealed enclosure, and the first water receiving section 44 receives and flows the air-containing rice-supplying water W3 separated by the separator 43 on the inside of the wall,
A first return pipe (pipe) 45 causes the air-containing rice water W3 flowing inside the wall surface of the first water receiving section 44 to fall and flow,
The system includes a flow pipe 46 that allows the pre-washed rice grains R2 separated by the separator 43 to flow into the immersion section 60 for the next step.

The first water receiving section 44 is covered with a lid 41 that can be detachably closed on its upper surface. Furthermore, by attaching connecting members (not shown) that can be easily attached and detached with simple operation to, for example, the lid 41 and the vicinity of the opening 31a of the rice supply pipe 31, the rice supply pipe 31 connected from the rice washing section 20 and the lid 41 are made detachable.

On the underside of the lid 41, a wall-shaped guide section 41a is attached. This guide section is a plate-like member formed in a circular shape when viewed from below, surrounding the opening 31a of the rice supply pipe 31, and positioned inside the separator 43. The guide section 41a extends approximately vertically from the underside of the lid 41. When the lid 41 is attached to the first water receiving section 44, the lower end of the guide section 41a is configured to be spaced apart from both the wall surface 43a of the separator 43 and the inclined section 42a and horizontal section 42b of the diffuser 42.

Furthermore, the opening 45a of the first return pipe 45 is connected to the lower part of the side surface of the first water receiving section 44. The first return pipe 45 continues to the overflow section 76 of the immersion section 60, which will be described later.

Furthermore, below the opening 31a of the rice delivery pipe 31 of the rice washing section 20 connected to the lid 41, there is a conical diffuser 42 fixed to the lower surface of the lid 41 via, for example, a rod-shaped stay (not shown). The conical diffuser 42 has its apex facing upward and, in a front cross-sectional view, has an inclined portion 42a that slopes with respect to the horizontal direction, and a horizontal portion 42b that extends substantially horizontally from the lower part of the inclined portion 42a. The horizontal portion 42b is formed around the edge of the conical diffuser 42. The diffuser 42 is located in the upper half of the cylindrical separator 43, which opens upwards and downwards.

More specifically, in the first diffusion step S40 described later, the direction of flow is changed to a nearly horizontal direction, and the mixed fluid M2 of the rice-transport water containing air with reduced kinetic energy and the pre-washed rice grains is positioned at a height that reaches the inside of the drainage section 43c on the wall surface 43a of the separator 43. This allows the first separation step S51, described later, to be performed effectively.

Furthermore, a gap is provided between the outer end of the horizontal section 42b of the diffuser 42 in the diametrical direction and the wall surface 43a, allowing the washed rice grains R2 to flow during the first separation step S51 and induction step S52, which will be described later.

As shown in Figures 4(a) and 4(b), the separator 43 is a cylindrical member made of, for example, stainless steel, with a roughly conical shape with its apex pointing downwards and openings at the top and bottom. The wall surface 43a, inclined at a predetermined angle to the horizontal, for example approximately 45 degrees, is divided into three sections from top to bottom: the upper flow section (flow section) 43b, the drain section 43c, and the lower flow section (flow section) 43d.

In the wall surface 43a of the separator 43, the drainage section 43c is provided with a plurality of substantially straight holes 43e, for example, inclined at a predetermined angle with respect to the horizontal direction. The upper flow section 43b and the lower flow section 43d do not have holes 43e.

The multiple holes 43e provided in the drainage section 43c are configured to be too small to allow pre-washed rice grains R2 to pass through. However, they are configured to allow broken pre-washed rice grains R2, or crushed rice grains R4, to pass through. The size of the crushed rice grains R4 that the holes 43e allow to pass through is determined by considering factors such as the type of rice and the effect the crushed rice grains R4 have on cooking. Note that in Figure 4(a), the holes 43e are omitted for clarity.

The multiple holes 43e provided in the drainage section 43c are formed in an elongated shape, with both ends of the elongated holes being semicircular. This prevents pre-washed rice grains R2 and crushed rice grains R4 from becoming trapped in the holes 43e, thereby suppressing a decrease in separation efficiency due to clogging of the holes 43e. Furthermore, it facilitates the cleaning of the separator 43 during the final step S120 described later.

The shape of the multiple holes 43e in the wall surface 43a of the separator 43, and the predetermined angles with respect to the horizontal direction, are not limited to those exemplified in this embodiment. For example, the multiple holes 43e in the wall surface 43a may be formed at multiple different angles with respect to the horizontal direction and combined.

Furthermore, as shown in Figure 4(c), the upper end of the wall surface 43a of the separator 43 has a plate-shaped top surface portion 43g that extends inward in a substantially horizontal direction. By placing the separator 43 on the flow pipe 46 within the first water receiving section 44 and covering the top of the first water receiving section 44 with the lid 41, the wall surface 43a, the top surface portion 43g, the lower surface of the lid 41, and the guide portion 41a attached to the lower surface of the lid 41 form a substantially continuous surface.

As shown in Figures 3 and 4(b), the lower part of the separator 43 has a fitting portion 43f that can be detachably installed by fitting it onto the upper end face of the fluid pipe 46 leading to the immersion tank 61 of the immersion section 60 where the next step is performed. This allows installation to be completed simply by fitting the fitting portion 43f of the separator 43 onto the fluid pipe 46, reducing the effort required to install the separator 43 in the correct position within the first water receiving section 44.

Furthermore, since the diffuser 42 in the separation unit 40 is fixed to the underside of the lid 41 via, for example, a rod-shaped stay, the diffuser 42 can be removed from the first water receiving unit 44 by removing the lid 41 from the first water receiving unit 44. Also, since the separator 43 is detachably installed on the fluid pipe 46, it can be easily removed from the first water receiving unit 44.

(3) Immersion section Next, the configuration of the immersion section 60 will be described.

The immersion section 60, shown in Figures 5 and 7, stores the pre-washed rice grains R2 separated by the separation section 40 while immersing them in the immersion water W4 stored in the immersion tank 61. The immersed rice grains R3 stored in the immersion tank 61 are then allowed to flow down to the rice distribution section 90 for the next step. Furthermore, the rice bran foam floating on the surface of the immersion water W4, along with the immersion water W4 stored in the immersion tank 61, is allowed to flow into the overflow section 76, causing an overflow.

As shown in Figures 1, 7, and 11, the immersion section 60 is
The pre-washed rice grains R2 that have fallen and flowed through the flow pipe 46 of the separation unit 40 are immersed in the stored soaking water W4 to absorb water and stored in the soaking tank 61,
A lid 62 is placed over the opening of the immersion tank 61 to prevent foreign matter from entering the immersion tank 61 from above,
A conical hat-shaped guide plate 64 guides the flow of soaked rice grains R3 in the soaking water W4 stored in the soaking tank 61,
By opening the valve 67, a water supply nozzle 68 sprays clean water W1 into the immersion tank 61 through the water supply pipe (piping) 66,
A water level detection means 69 detects the water level of the immersion water W4 stored in the immersion tank 61 and sends an electrical signal to the control panel 141,
A storage amount detection means 70, which is a paddle-type sensor that detects when a predetermined amount of soaked rice grains R3 has been stored in the soaking tank 61 and sends an electrical signal to the control panel 141,
The two substantially parallel frames 71 are provided horizontally and are detachably secured at both ends to four protrusions (not shown) provided on the edge of the immersion tank 61,
A gate-shaped plate-shaped fixed partition member (partition member) 72 is attached to each of the two roughly parallel frames 71 and partitions the rice bran foam floating on the surface of the immersion water W4 stored in the immersion tank 61,
A plate-shaped movable partition member (partition member) 73 is rotatably attached by hinges 74 fixed to each fixed partition member 72,
The opening 45a of the first return pipe 45 is connected from above, and the overflow section 76 is a water channel that allows the immersion water W4 stored in the immersion tank 61 to overflow and flow when the water level exceeds a predetermined level.
The opening 77a is connected below the overflow section 76, and the second return pipe (pipe) 77 causes the air-containing rice supply water W3, which flows down the first return pipe 45, and the immersion water W4, which is stored in the immersion tank 61 and flows through the overflow section 76 due to overflow, to flow down.
A pipe 78 connects from a flow opening 61a located at the bottom of the immersion tank 61 to the rice distribution section 90 where the next process is carried out,
A rice distribution valve (valve) 79, which closes to store soaked rice grains R3 in the soaking tank 61, and opens for a predetermined time to allow the soaking water W4 and the soaked rice grains R3 stored in the soaking tank 61 to flow down to the rice distribution section 90 through the piping 78,
It is equipped with.

As shown in Figure 7, below the opening 46a of the fluid pipe 46 in the separation section 40, there is an immersion tank 61, which is a cylindrical tank with an open top and a conical shape with its lower part pointing downwards. The lower part of the immersion tank 61 has a fluid opening 61a, and a rice distribution valve 79 is attached to the piping 78 connected to the fluid opening 61a.

The rice distribution valve 79, when closed, stores the soaking water W4 stored in the soaking tank 61 and the flowing pre-washed rice grains R2 in the soaking tank 61, maintaining them in a soaked state as soaked rice grains R3. Furthermore, by opening the rice distribution valve 79, the soaking water W4 and soaked rice grains R3 stored in the soaking tank 61 are allowed to flow down into the separate rice distribution container 92 of the rice distribution section 90, described later, located below the soaking tank 61.

As shown in Figure 7, the water level when the immersion tank 61 is filled with immersion water W4 is referred to as H3.

Furthermore, a lid 62 that can be detachably closed over the opening (not indicated by a reference numeral) at the top of the immersion tank 61 is placed over the immersion tank 61. The lid 62 is equipped with multiple handles 62a to facilitate removal, and a notch is provided in its approximate central portion to allow clearance for the fluid pipe 46. It is preferable that the lid 62 be divided, for example, into two sections when viewed from above, to facilitate removal.

As shown in Figures 5 and 7, one end of several plate-shaped support members 63, which are placed on the bottom of the immersion tank 61, is fixed to the underside of the guide plate 64 by welding or other means, and the other end of each support member 63 is placed on the bottom of the immersion tank 61. In this embodiment, as shown in Figure 5, eight support members 63 are fixed to the guide plate 64 in a top view.

By placing the other end of the support member 63, which is fixed to the underside of the guide plate 64, on the bottom of the immersion tank 61, a predetermined gap is formed between the conical outer edge of the guide plate 64 and the inner surface of the immersion tank 61, allowing the immersed rice grains R3 to flow through this predetermined gap. The predetermined gap is set, for example, to 50-60 mm. One end of a chain 65, for example made of stainless steel, is connected to the top of the guide plate 64. The other end of the chain 65 is connected to the upper edge of the immersion tank 61, and by pulling up the chain 65, the guide plate 64 and support member 63 can be lifted from the bottom of the immersion tank 61.

As shown in Figure 8, the soaked rice grains R3 stored in the soaking tank 61 are arranged so that their ridges 80 have an angle of repose θ1 with respect to the horizontal, for example, approximately 35 degrees. The hypotenuse of the conical guide plate 64 has an angle θ2 with respect to the horizontal, for example, approximately 30 degrees. Angle θ2 is formed to be smaller than the angle of repose θ1.

The angle of repose of the soaked rice grains R3, which are stored in a mound-like structure in the soaking water W4, will change depending on the type of rice used, but will be approximately 35 degrees. If it changes significantly, the angle of repose corresponding to that change should be used as θ1. Furthermore, it is preferable to change the angle θ2 of the hypotenuse of the guide plate 64 relative to the horizontal to match the angle of repose θ1.

As shown in Figure 9, the guide plate 64, with a support member 63 fixed to its underside, which is placed on the bottom of the immersion tank 61, can be lifted from the bottom of the immersion tank 61 by pulling the chain 65 upward. Alternatively, by slowly lowering the guide plate 64, with the support member 63 fixed to its underside, into the immersion tank 61 while pulling the chain 65 upward, the other end of the support member 63 can be placed on the bottom of the immersion tank 61, and the guide plate 64 can be repositioned at the bottom of the immersion tank 61.

As shown in Figures 1 and 7, the immersion section 60 is provided with a water supply pipe 66, which is connected to, for example, a water tap. A water supply nozzle 68 is provided at the end of the water supply pipe 66, which is located inside the immersion tank 61. By opening the valve 67, clean water W1 is injected and supplied to the immersion tank 61, where it is stored as immersion water W4.

Furthermore, as shown in Figure 11, the immersion tank 61 is equipped with a water level detection means 69, such as a float-type level sensor. The water level detection means 69 detects when the water level of the immersion water W4 stored in the immersion tank 61 is below a predetermined water level H3, which is the water level when the immersion tank 61 is full.

When the water level of the immersion water W4 stored in the immersion tank 61 is detected to be below the water level H3, an electrical signal is sent to the control panel 141 (described later), and from the control panel 141, an electrical signal is sent to the valve 67 to open the valve 67. Then, clean water W1 is injected into the immersion tank 61 from the water supply nozzle 68 through the water supply pipe 66 until the water level of the immersion water W4 in the immersion tank 61 reaches H3.

As shown in Figures 7 and 8, the water supply nozzle 68 is positioned higher than the water level H3 of the immersion water W4 stored in the immersion tank 61 to its maximum capacity. Furthermore, it is positioned higher than a predetermined water level in the immersion water W4 when a predetermined amount of pre-washed rice grains R2 falls into the water W4 stored in the immersion tank 61 to its maximum capacity H3. This prevents the immersion water W4 stored in the immersion tank 61 from flowing back into the water supply pipe 66 through the water supply nozzle 68.

Furthermore, two water supply nozzles 68 are provided, positioned opposite the overflow section 76, so that the direction of the clean water W1 injection is directed toward the overflow section 76. One nozzle is configured to inject the clean water W1 at a predetermined angle downward from the horizontal, for example, at an angle of 20 degrees downward from the horizontal, while the other nozzle is configured to inject the clean water W1 in a nearly horizontal direction (see Figure 5).

As shown in Figure 8, a paddle-type sensor, the storage volume detection means 70, is attached to the wall of the immersion tank 61. Within the immersion water W4 stored in the immersion tank 61, the storage volume detection means 70 rotates its paddle-like tip (not indicated) around the longitudinal axis of a shaft positioned approximately horizontally.

When a predetermined amount of soaked rice grains R3 is stored in the soaking water W4 in the soaking tank 61, the paddle portion touches the ridge line 80 of the soaked rice grains R3, and the storage amount detection means 70 detects the resistance of the rotation of the paddle portion. Upon detection of resistance, the storage amount detection means 70 sends an electrical signal to the control panel 141 (described later), which displays that the amount of soaked rice grains R3 stored in the soaking tank 61 has reached a predetermined amount. It then issues a warning to stop the supply of polished rice grains R1 to the introduction guide 21 of the rice washing unit 20.

As shown in Figures 5 and 7, the ends of two parallel frames 71, extending horizontally, are detachably secured to four protrusions (not shown) on the upper edge of the immersion tank 61. The four protrusions on the upper edge of the immersion tank 61 are shorter, plate-like members with flat top surfaces, to which the ends of the frames 71 are detachably secured. This allows the support members 63 and guide plates 64 to be lifted from the bottom of the immersion tank 61 and cleaned by removing the frames 71 from the four protrusions on the edge of the immersion tank 61 and then pulling the chain 65 upwards.

As shown in Figures 10(a) and 11, the lower ends of the inner opening 72d of the gate-shaped fixed partition member 72 are provided with notches 72c that are chamfered in a direction inclined to the horizontal. Furthermore, by bending the upper end of the fixed partition member 72, a nearly horizontal bent portion 72a is formed, and by further folding its end back, a nearly vertical folded portion 72b is formed. The fixed partition member 72 is then secured to four protrusions provided on the edge of the immersion tank 61, and the bent portion 72a and folded portion 72b of the fixed partition member 72 are placed and secured to each of the two horizontally positioned frames 71.

Furthermore, as shown in Figure 10(b), a movable compartment member 73 is rotatably attached to a hinge 74 mounted on a fixed compartment member 72 formed in a gate shape. Also, as shown in Figure 11, the hinge 74 is configured to be located below the water level H3 of the immersion water W4 stored in the immersion tank 61.

Furthermore, the movable compartment member 73 can be rotated toward the outside of the immersion tank 61 by a hinge 74 attached to the fixed compartment member 72, allowing the movable compartment member 73 to rotate freely relative to the fixed compartment member 72. Alternatively, the movable compartment member 73 may be configured to rotate only toward the outside of the immersion tank 61.

Alternatively, holes may be drilled in the bent portion 72a of the fixed compartment member 72 and the frame 71, and the bent portion 72a of the fixed compartment member 72 and the frame 71 may be fixed together with bolts and nuts. However, in that case, if the bolts and nuts fixing the bent portion 72a of the fixed compartment member 72 and the frame 71 were to loosen and come off, they might fall into the immersion tank 61 and become mixed with the immersed rice grains R3. Therefore, it is preferable not to fix the bent portion 72a of the fixed compartment member 72 and the frame 71 together with bolts and nuts.

As shown in Figures 5, 7, and 11, two fixed partition members 72 and a movable partition member 73, each attached to one of the two frames 71, are installed to partition the inside of the wall surface of the immersion tank 61. When immersion water W4 is filled to the water level H3, the water surface at water level H3 is partitioned between the two fixed partition members 72 and the inside of the wall surface of the immersion tank 61. This partitioned area of water surface is called the partitioned area 75. The partitioned area 75 is the area indicated by hatching in Figures 5 and 6.

As shown in Figure 6, an overflow section 76, roughly triangular in shape when viewed from above, is provided at the upper part of the wall surface of the immersion tank 61, communicating with the wall surface of the immersion tank 61. The overflow section 76 is positioned opposite the water supply nozzle 68, and is located in the direction of the spray of clean water W1 ejected from the water supply nozzle 68.

As shown in Figure 7, the opening 45a of the first return pipe 45 is positioned so as to face downwards at the upper part of the overflow section 76, which communicates with the upper part of the wall of the immersion tank 61. The opening 77a of the second return pipe 77 is connected to the lower part of the overflow section 76.

The overflow section 76 directs the immersion water W4, etc., that overflows from the compartmentalized area 75, which is partitioned by the fixed compartmentalizer 72 and the inside of the wall surface of the immersion tank 61, to the second return pipe 77.

The overflow section 76 has a wall portion 76a that rises vertically at the boundary with the immersion tank 61. When the immersion tank 61 is filled with immersion water W4, the water level H3 reaches approximately the upper end of the wall portion 76a.

The wall portion 76a allows for a predetermined height at its upper end, thereby pre-determining the water level at which the immersion water W4 stored in the immersion tank 61 overflows into the overflow portion 76. Furthermore, the provision of the wall portion 76a prevents the immersion water W4 that has flowed into the overflow portion 76 from flowing back into the immersion tank 61.

The second return pipe 77, whose upper end is connected to the overflow section 76, is connected to the first purification tank 121 of the purification section 120, which will be described later.

As shown in Figure 11, when the immersion tank 61 is filled with immersion water W4 up to a water level H3, the opening 46a of the flow pipe 46 is located within the compartment 75 at a distance H4, for example, approximately 10 to 20 millimeters below the water level H3. That is, when the water level of the immersion water W4 is at water level H3, the opening 46a of the flow pipe 46 is located within the immersion water W4 in the compartment 75. Furthermore, the lower ends of the fixed compartment member 72 and the movable compartment member 73 are located at a distance H5, for example, 120 to 130 millimeters below the water level H3 of the immersion water W4 stored in the immersion tank 61.

Furthermore, even if the immersion tank 61 is filled with a predetermined amount of immersed rice grains R3, if the configuration ensures that the edges 80 of the immersed rice grains R3 do not come into contact with the lower end of the fixed partition member 72, then the movable partition member 73 does not need to be attached to the fixed partition member 72. In that case, the shape of the fixed partition member 72 shown in Figure 10 can be made substantially rectangular instead of gate-shaped, making the manufacturing of partition members 72 and 73 easier.

The shape of the movable partition member 73, which is rotatably attached to the fixed partition member 72, is merely an example. For example, it is also possible to attach one or more movable partition members to the opening 72d of the fixed partition member 72 so that it opens in a single-leaf or double-leaf configuration.

In this embodiment, the partitioning member is configured by attaching the movable partitioning member 73 to the fixed partitioning member 72. However, the partitioning member may also be composed solely of the movable partitioning member 73. In that case, for example, the upper end of the movable partitioning member 73 may be provided with a bent portion and a folded portion similar to those of the fixed partitioning member 72, and it may be placed on and locked to each of the two frames 71. The movable partitioning member 73 is then configured to move relative to the frame 71. Furthermore, another different movable partitioning member may be attached to the lower part of the movable partitioning member 73.

(4) Rice Distribution Section Next, the configuration of the rice distribution section 90 will be explained.

The rice distribution unit 90 shown in Figure 14 allows the soaked rice grains R3 and soaking water W4, which have been soaked in the soaking unit 60, to fall and flow into the separation and distribution container 92. This separates the soaking water W4 from the soaked rice grains R3, and then distributes a predetermined amount of soaked rice grains R3 to the rice cooker 97.

The rice distribution unit 90 is,
A separation and distribution container 92 stores a predetermined amount of soaking water W4 and soaking rice grains R3 that flow down through the piping 78 of the soaking tank 61, and separates the soaking water W4 from the soaking rice grains R3 through a plurality of holes 92a (not shown) provided on the cylindrical wall surface,
A rice distribution amount regulator 91 is used in combination with the separate rice distribution container 92 to adjust the amount of soaked rice grains R3 that are dropped and flowed into the separate rice distribution container 92 through the piping 78 of the soaking tank 61 and stored in the container.
A second water receiving section 93 receives the immersion water W4 separated by the rice separation container 92 on the inside of the wall surface,
A drain pipe (piping) 94 is connected to the lower part of the second water receiving section 93 and drains the immersion water W4 received by the second water receiving section 93,
A plate-shaped shutter 95 closes the lower part of the rice separation container 92 to store soaked rice grains R3 in the rice separation container 92, and is driven by a movable drive means 96, such as an air cylinder, to open the shutter for a predetermined time, thereby supplying a predetermined amount of soaked rice grains R3 stored in the rice separation container 92 to the rice cooker 97 located below for distribution.
It is equipped with.

The lower end of the piping 78 of the immersion section 60 is positioned inside the rice separation container 92. Near the lower end of the piping 78, a rice distribution amount regulator 91 is attached, formed to close the upper opening of the cylindrical rice separation container 92 (which has openings at the top and bottom), and to be movable in the vertical direction. By moving the rice distribution amount regulator 91 vertically, the volume inside the rice separation container 92 is changed, thereby altering the amount of immersed rice grains R3 stored as they flow from the immersion tank 61 through the piping 78.

The cylindrical rice separation container 92 has multiple holes 92a (not shown) in its walls, sized to prevent the soaked rice grains R3 from passing through. By opening the rice distribution valve 79, the soaking water W4 from the soaking water flowing down the piping 78 of the soaking section 60 and the soaked rice grains M3 is separated by flowing through the multiple holes 92a to the outside of the walls of the rice separation container 92. The separated soaking water W4 is received by a second water receiving section 93, which is positioned to surround the rice separation container 92.

A drain pipe 94 is connected to the lower part of the second water receiving section 93, and the immersion water W4 received in the second water receiving section 93 is drained through the drain pipe 94.

After closing the rice distribution valve 79, the shutter 95 attached to the bottom of the separated rice distribution container 92 is driven by the drive means 96, causing a predetermined amount of soaked rice grains R3 to fall and be supplied to the rice cooker 97 placed on a conveyor 98 located below the shutter 95. Furthermore, a predetermined amount of cooking water W6 is supplied to the rice cooker 97 by the water supply unit 100, which will be described later. The conveyor 98 on which the rice cooker 97 is placed continues to a lid-covering device (not shown) that covers the rice cooker 97 with a lid (not shown), and further continues to a rice cooking device (not shown) that heats the lidded rice cooker 97 at a high temperature.

(5) Water supply section Next, the configuration of the water supply section 100 will be explained.

The water supply unit 100 shown in Figure 14 supplies a predetermined amount of cooking water W6 at a predetermined temperature to the rice cooker 97 into which a predetermined amount of soaked rice grains R3 has been supplied.

The water supply unit 100 is
A tank 104 for storing the rice cooking water W6, which is clean water W1,
The water level of the cooking water W6 stored in the tank 104 is controlled by the float valve 103, and a water supply pipe (piping) 101 supplies clean water W1 to the tank 104 until the cooking water W6 stored in the tank 104 reaches a predetermined level, for example, a level where 50 to 60 liters of water are stored in the tank 104.
A valve 102 is provided in the water supply pipe 101 and, when opened manually, supplies clean water W1 to the tank 104 through the water supply pipe 101.
A heater 105 is used to raise the temperature of the cooking water W6 stored in the tank 104 to a predetermined temperature and maintain that temperature using a temperature sensor (not shown).
By opening the valve 107 for a predetermined time, a predetermined amount of cooking water W6, heated to a predetermined temperature by the heater 105, is supplied to the rice cooker pot 97 located below the shutter 95 of the rice distribution section 90 via a pipe 106.
It is equipped with.

Alternatively, the valve 102 may be configured as a solenoid valve or an electric valve, electrically connected to the control unit 140, and the valve 102 may be opened and closed by the control unit 140.

(6) Purification section Next, the configuration of the purification section 120 will be explained.

The purification unit 120 shown in Figure 15 removes rice bran foam and crushed rice grains R4 from the air-containing rice supply water W5, which is a mixture of soaking water, and purifies it so that it can be used again in the rice washing unit 20 to wash polished rice grains R1.

As shown in Figures 1 and 15, the purification unit 120 is
The second return pipe 77 of the immersion section 60 is connected to the side wall, and the first purification tank 121 stores the air-containing rice supply water W5, which is a mixture of the immersion water flowing down the second return pipe 77, as rice supply water W2.
When the water supplied with rice W2 stored in the first purification tank 121 exceeds a predetermined water level, the drain hopper 122 causes the water supplied with rice W2 to overflow, and the rice bran foam floating on the surface of the water supplied with the water supplied with rice W2 is drained through the drain pipe (piping) 122a.
A third return pipe (pipe) 125 adjusts the flow rate using a valve 126 and causes the rice water W2 stored in the first purification tank 121 to flow to the second purification tank 128,
A plate-shaped flow restricting member 127 is installed in the first purification tank 121 and prevents the flow of air-containing rice supply water W5, which is a mixture of immersion water that flows down through the second return pipe 77, from flowing directly from the first purification tank 121 to the third return pipe 125 and then directly to the second purification tank 128.
A second purification tank 128 stores the rice water W2 that has been flowed from the first purification tank 121 through the third return pipe 125,
A float valve 129 is used to detect the water level of the rice-supplied water W2 stored in the second purification tank 128, and a water supply pipe 130 is used to supply clean water W1 to the second purification tank 128 when the water level falls below a predetermined level.
A valve 131 is provided in the water supply pipe 130 and, when opened manually, supplies clean water W1 to the second purification tank 128 through the water supply pipe 130.
An overflow water drain pipe 132 is inserted into a drain port 128a located at the bottom of the second purification tank 128, and when the rice-supplied water W2 stored in the second purification tank 128 exceeds a predetermined water level, it overflows from the upper opening and is drained as overflow water.
By opening the valve 124, the water supplied with rice W2 stored in the first purification tank 121, the rice bran foam stored in the first purification tank 121, and the crushed rice grains R4 stored in the first purification tank 121 are discharged from the drain pipe (piping) 123 located at the bottom of the first purification tank 121.
By removing the overflow water drain pipe 132 from the drain port 128a, a drain pipe 133 is installed at the bottom of the second purification tank 128 to discharge the rice water W2 and rice bran foam stored in the second purification tank 128,
It is equipped with.

As shown in Figure 15, the second return pipe 77 is connected to the side of the first purification tank 121. The first purification tank 121 is a rectangular tank in top view with an open top, and its lower part is shaped like a square pyramid with its apex pointing downwards. A drain pipe 123 with a valve 124 is connected to the apex of the downward-pointing square pyramid at the bottom of the first purification tank 121. By opening the valve 124, the drain pipe 123 discharges the rice-transport water W2 stored in the first purification tank 121.

Inside the first purification tank 121 is a rectangular hopper with an open top, and below it is a drain hopper 122 with a square pyramidal shape pointing downwards. The lower apex of the drain hopper 122 is connected to a drain pipe 122a. When the water level H6 of the rice-transporting water W2 stored in the first purification tank 121 exceeds the water level up to the edge of the upper opening of the drain hopper 122, it overflows through the drain hopper 122 and is drained through the drain pipe 122a.

One end of the third return pipe 125, which has a valve 126, is connected to the side of the first septic tank 121 opposite to the side to which the second return pipe 77 is connected. The other end of the third return pipe 125 is connected to the side of the second septic tank 128.

Furthermore, within the first purification tank 121, a plate-shaped flow restricting member 127 is provided near the wall surface of the first purification tank 121 at the point where one end of the third return pipe 125 is connected, between the point where the second return pipe 77 is connected and the point where one end of the third return pipe 125 is connected.

The plate-shaped flow restricting member 127 is positioned approximately perpendicular to the flow direction of the air-containing rice supply water W5, which is a mixture of immersion water and air, flowing from the second return pipe 77 to the first purification tank 121, so as not to flow directly into the third return pipe 125.

The second purification tank 128, to which the other end of the third return pipe 125 is connected on its side, is equipped with a water supply pipe 130 that detects the water level of the rice-transporting water W2 stored in the second purification tank 128 via a float valve 129 and supplies clean water W1 to the second purification tank 128 when the water level falls below a predetermined level H7. A valve 131 is provided in the water supply pipe 130, and by opening the valve 131, clean water W1 is supplied, allowing the rice-transporting water W2 to be stored in the second purification tank 128.

Furthermore, the second purification tank 128 is approximately cubic in shape, and has a drain port 128a at its bottom. An overflow drain pipe 132 is inserted into the drain port 128a to allow the rice-supplied water W2 stored in the second purification tank 128 to flow out when the water level exceeds a predetermined water level H7.

The rice-supplying water W2 stored in the second purification tank 128 overflows when it exceeds the water level H7, which is reached when the water level is filled to the edge of the upper opening of the overflow drain pipe 132. The overflow drain pipe 132 is constructed so that the edge of its upper opening is approximately equal to or slightly higher than the water level H7.

From the side of the second purification tank 128, a pipe 28 is connected via a mesh filter 134, leading to the pump 29 of the rice washing section 20.

The water level H3 in the immersion tank 61 shown in Figure 7, when filled with immersion water W4, is configured to be higher than the water level H6 in the first purification tank 121 shown in Figure 15.

As a result, when the water level of the immersion water W4 stored in the immersion tank 61 exceeds the water level H3, the immersion water W4 overflows beyond the upper end of the wall 76a of the overflow section 76, and can be allowed to flow down to the first purification tank 121 through the second return pipe 77 by gravity, without the need for a pump or other equipment.

(7) Control Unit Next, the configuration of the control unit 140 will be described.

The control unit 140 shown in Figure 1 is electrically connected to the equipment in each section and performs centralized control.

The control unit 140 includes a control panel 141 that electrically connects to and controls each component and equipment, as described below.
- The pump 29 of the rice washing section 20 is electrically connected to control its operation and stopping. By driving the pump 29, the rice water W2 stored in the second purification tank 128 is discharged to the ejector 26. By stopping the pump 29, the discharge of rice water W2 to the ejector 26 is stopped.
- The valve 24 of the rice washing section 20 is electrically connected to control its opening and closing. Opening the valve causes clean water W1 to be sprayed from the clean water nozzle 25 attached to the inside of the wall surface of the receiving cylinder 22. Closing the valve stops the spraying of clean water W1 from the clean water nozzle 25.
- The valve 67 of the immersion section 60 is electrically connected and receives an electrical signal from the water level detection means 69 to control opening and closing. Opening the valve allows fresh water W1 to be sprayed into the immersion tank 61 from the water supply nozzle 68. Closing the valve stops the spraying of fresh water W1 from the water supply nozzle 68.
- The immersion section 60 is electrically connected to the storage volume detection means 70 and receives an electrical signal from the storage volume detection means 70.
- The rice distribution valve 79 of the immersion section 60 is electrically connected to control its opening and closing. Opening the valve allows the immersion water and immersed rice grains M3 stored in the immersion tank 61 to flow down through the piping 78 to the separate rice distribution container 92. Closing the valve stops the flow of the immersion water and immersed rice grains M3.
- It is electrically connected to the drive means 96 that drives the shutter 95 of the rice distribution section 90, and controls the opening and closing of the opening at the bottom of the separated rice distribution container 92.
- By electrically connecting to the valve 107 of the water supply unit 100 and opening and closing it, a predetermined amount of cooking water W6 is supplied to the rice cooker pot 97.
- The heater 105 of the water supply unit 100 and a temperature sensor (not shown) provided in the tank 104 are electrically connected to adjust the cooking water W6 to a predetermined temperature.

(Operation of the rice cooking pre-processing system)
The operation of the rice pre-processing system 10 of this embodiment will be described below.

The operation of the rice pre-processing system 10 in one embodiment of the present invention is broadly composed of the following, as shown in Figure 16.
(1) Preparation step S10: Preparation to carry out each of the steps from (1) onward.
(2) Supply step S20: Supply the pre-prepared polished rice grains R1 to the rice washing section 20.
(3) In the rice washing step S30, air, the rice supply water W2, and the polished rice grains R1 supplied in the supply step S20 are mixed to form a mixed fluid M1 of air-containing rice supply water and polished rice grains, and the polished rice grains R1 are washed by flowing this mixed fluid M1 of air-containing rice supply water and polished rice grains within the rice washing means 32.
(4) Diffusion step S40: The mixed fluid M2 of the rice-washing water containing air and the washed rice grains after the rice-washing step S30 is diffused in a substantially horizontal direction by the diffuser 42 in the separator 43.
(5) The mixed fluid M2 of the air-containing rice water and pre-washed rice grains diffused in the diffusion step S40 is brought to the wall surface 43a of the separator 43, and the first separation step (separation step) S51 separates the air-containing rice water W3 and the pre-washed rice grains R2 by the drainage section 43c of the separator 43.
(6) Of the mixed fluid M2 of the air-containing water and pre-washed rice grains that has been diffused in the diffusion step S40, the mixed fluid M2 of the air-containing water and pre-washed rice grains that has reached the wall surface 43a, has its flow direction changed downward by the guide section 41a and is guided to the drain section 43c in the guide step S52.
(7) The second separation step (separation step) S60 involves mixing the pre-washed rice grains R2 remaining inside the separator 43 after separation in the first separation step S51 with the mixed fluid M2 of air-containing rice water and pre-washed rice grains that has been guided to the drainage section 43c by the induction step S52, and separating the mixed fluid M2 of air-containing rice water and pre-washed rice grains into air-containing rice water W3 and pre-washed rice grains R2 by the drainage section 43c of the separator 43.
(8) Flow step S70, which causes the pre-washed rice grains R2 separated in the first separation step S51 and the second separation step S60 to fall and flow downward, and the pre-washed rice grains R2 separated on the inside of the wall surface 43a to flow downward with the air-containing rice water W3 that could not be separated from the mixed fluid M2 of air-containing rice water and pre-washed rice grains in the first separation step S51 and the second separation step S60.
(9) In the immersion step S80, the washed rice grains R2 separated in the separation steps S51 and S60 are immersed in the immersion water W4 stored in the immersion tank 61, and the rice bran foam floating on the surface of the immersion water W4 is made to flow out along with the immersion water W4 stored in the immersion tank 61.
(10) In the soaking step S80, the soaked rice grains R3 are supplied in a predetermined amount to the rice cooker pot 97 in the rice distribution section 90 in the rice distribution step S90.
(11) Water supply step S100: A predetermined amount of cooking water W6 is supplied from the water supply unit 100 to the rice cooker 97 to which the soaked rice grains R3 were supplied in the rice distribution step S90.
(12) The air-containing rice water W3 separated in the first separation step S51 and the second separation step S60, and the immersion water W4 that overflowed in the immersion step S80 are mixed to form air-containing rice water W5 mixed with immersion water, and the mixture is purified in the purification unit 120 in the purification step S110.
(13) Distribute a predetermined amount of polished rice grains R1 to be washed as soaked rice grains R3 into the rice cooker pot 97, add a predetermined amount of cooking water W6, and then complete step S120 to prepare for the next preparation step S10.

(1) Preparation step In the rice cooking pre-processing system 10 of this embodiment, first a preparation step S10 is performed to prepare for each of the following steps.

First, power is turned on to the control panel 141 of the control unit 140 shown in Figure 1.

Next, the valve 67 of the water supply pipe 66 of the immersion section 60 is opened, and clean water W1 is injected from the water supply nozzle 68 through the water supply pipe 66 to be stored in the immersion tank 61 as immersion water W4. When the immersion water W4 stored in the immersion tank 61 reaches the water level H3 (see Figure 7), the water level detection means 69 detects the water level H3 of the immersion water W4 stored in the immersion tank 61 and sends an electrical signal to the control panel 141. The control panel 141 then receives this electrical signal and closes the valve 67 of the water supply pipe 66.

The valve 102 of the water supply unit 100 is opened, and fresh water W1 is supplied to the tank 104 through the water supply pipe 101 and stored as cooking water W6. When the cooking water W6 stored in the tank 104 reaches a predetermined level, the float valve 103 is activated, and the supply of fresh water W1 from the water supply pipe 101 is stopped. Then, the control panel 141 activates the heater 105, raising the temperature of the cooking water W6 stored up to the predetermined level to a predetermined temperature and maintaining that temperature.

The valve 131 of the purification unit 120 is opened, and clean water W1 is supplied to the second purification tank 128 through the water supply pipe 130 and stored as rice-supplying water W2. When the stored rice-supplying water W2 reaches a predetermined water level H7 (see Figure 15), the float valve 129 operates, and the supply of clean water W1 from the water supply pipe 130 stops. At this time, the predetermined water level H7 is approximately equal to, or slightly lower than, the edge of the upper opening of the overflow water drain pipe 132.

Furthermore, the supplied rice water W2 flows from the second purification tank 128 through the third return pipe 125 to the first purification tank 121, where it is stored up to the same water level H7. The flow rate of the supplied rice water W2 flowing between the second purification tank 128 and the first purification tank 121 through the third return pipe 125 is regulated by valve 126.

The pump 29 in the rice washing section 20 is driven, and the water W2 stored in the second purification tank 128 is discharged and flowed into the ejector 26 of the rice washing section 20. Furthermore, the valve 24 of the rice washing section 20 is opened, and the injection of clean water W1 from the clean water nozzle 25 into the inner wall of the receiving cylinder 22 begins.

The rice water W2 is mixed with the air in the receiving cylinder 22 and the clean water W1 sprayed from the clean water nozzle 25 by the ejector 26, and passes through to become rice water W3 containing air. This air-containing rice water W3 then flows almost vertically through the rice supply pipe 31 and the rice washing means 32 to the diffuser 42 of the separation unit 40. The water level in the second purification tank 128 decreases, but clean water W1 is supplied by the float valve 129 to maintain the water level H7.

The air-containing rice-transport water W3 that reaches the upper surface of the diffuser 42 changes its flow direction to a nearly horizontal direction due to the inclined section 42a and the horizontal section 42b, and then flows through the multiple holes 43e provided in the wall surface 43a of the separator 43 to the first water receiving section 44. It then flows inside the first water receiving section 44 and flows to the first return pipe 45.

The air-containing rice water W3 that flows into the first return pipe 45 flows down into the overflow section 76 of the immersion section 60, and then flows down into the second return pipe 77. The air-containing rice water W3 flowing down the second return pipe 77 flows into the first purification tank 121 of the purification section 120 and is stored there.

Then, the air-containing rice water W3 flows into and is stored in the first purification tank 121 until it reaches a predetermined water level H6 (see Figure 15). At this time, the water level in the second return pipe 77 also reaches the same level as the predetermined water level H6.

Furthermore, at this time, the balance between the overflow flow rate from the drain hopper 122 of the first purification tank 121 and the overflow flow rate from the overflow water drain pipe 132 of the second purification tank 128 is adjusted by the valve 126 of the third return pipe 125.

Finally, the position of the rice distribution amount adjuster 91 is adjusted so that a predetermined amount of soaked rice grains R3 is stored in the rice distribution container 92 of the rice distribution unit 90, and the preparation step S10 is completed.

(2) Supply step After the preparation step S10 is completed, the supply step S20 is performed to supply the pre-prepared polished rice grains R1 to the rice washing section 20.

As shown in Figure 2, the operator supplies pre-prepared polished rice grains R1 to the introduction guide 21 of the rice washing section 20. It is preferable that the polished rice grains R1 supplied to the introduction guide 21 are pre-configured for the pre-cooking processing system 10. For example, the configuration of the pre-cooking processing system 10 may change depending on the degree of polishing (whiteness) of the polished rice grains R1.

In addition, in supply step S20, the operator supplies the polished rice grains R1 to the introduction guide 21. However, it is also possible to configure the system to automatically supply the polished rice grains R1 to the introduction guide 21 by installing a rice silo (not shown) for storing the polished rice grains R1, a weighing device (not shown) for dispensing a predetermined amount of polished rice grains R1 from the rice silo, and a rice lifting machine (not shown) for transporting the polished rice grains R1 dispensed from the weighing device.

In this case, the weighing device and rice lifter continue to supply polished rice grains R1 by the weighing device and the rice lifter until a predetermined amount of polished rice grains R1, as set in advance by the control panel 141, is supplied to the introduction guide 21, or until the storage amount detection means 70 installed in the immersion tank 61 detects a predetermined amount of immersed rice grains R3 stored in the immersion tank 61.

(3) Rice washing step After starting the supply step S20, air, the supplied water W2, and the polished rice grains R1 supplied in the supply step S20 are mixed to form a mixed fluid M1 of supplied water containing air and polished rice grains, and the rice washing step S30 is performed to wash the polished rice grains R1 by flowing this mixed fluid M1 of supplied water containing air and polished rice grains within the rice washing means 32.

As shown in Figure 2, the water W2 supplied to the rice, stored in the second purification tank 128, is drawn into the pump 29 via the filter 134 and discharged, flowing into the ejector 26. Meanwhile, the polished rice grains R1 supplied in the supply step S20 are guided by the introduction guide 21, pass through the receiving cylinder 22, and are drawn into the suction port 27 along with the air inside the receiving cylinder 22. At that time, the polished rice grains R1 adhering to the inside of the wall of the receiving cylinder 22 flow together with the clean water W1 sprayed from the clean water nozzle 25 attached to the inside of the wall of the receiving cylinder 22, and are drawn into the suction port 27.

In this way, the polished rice grains R1 and clean water W1, which are drawn into the suction port 27, are drawn into the suction port 27 along with the air in the receiving cylinder 22, and are mixed with the flowing rice water W2 discharged from the pump 29 in the ejector 26 to form a mixed fluid M1 of air-containing rice water and polished rice grains.

The mixed fluid M1 of air-containing rice water and polished rice grains, which is mixed in the ejector 26 and flowed into the rice delivery pipe 31, flows through a rice washing means 32, such as a static mixer, which is incorporated into the middle of the rice delivery pipe 31. This washes the polished rice grains R1 into pre-washed rice grains R2. Then, the mixed fluid M2 of air-containing rice water and pre-washed rice grains flows through the rice delivery pipe 31 towards the separation unit 40.

When polished rice grains R1 are washed by passing them through the rice washing means 32, some of the polished rice grains R1 break due to the impact of contact with the rice washing means 32, other polished rice grains R1, and the inner wall of the rice delivery pipe 31, becoming crushed rice grains R4. These crushed rice grains R4, along with the mixed fluid M2 of air-containing rice delivery water and already washed rice grains, flow through the rice delivery pipe 31 and proceed to the separation section 40.

(4) Diffusion step After the rice washing step S30 is completed, a diffusion step S40 is performed in which the mixed fluid M2 of the rice water containing air after the rice washing step S30 and the washed rice grains is diffused in a substantially horizontal direction by the diffuser 42 in the separator 43.

As shown in Figure 3, the mixed fluid M2 of air-containing rice water and pre-washed rice grains flows through the rice supply pipe 31 to the separation section 40, and then flows downward in a nearly vertical direction from the opening 31a of the rice supply pipe 31 attached to the lid 41, retaining its kinetic energy as it reaches the inclined section 42a of the diffuser 42.

When the mixed fluid M2 of air-containing rice water and pre-washed rice grains reaches the inclined section 42a of the diffuser 42, the direction of flow changes to follow the inclined section 42a, spreading 360 degrees in a top view along the conical shape.

At this time, the mixed fluid M2 of air-containing water and pre-washed rice grains reaches the inclined section 42a of the diffuser 42, and the direction of flow is changed, causing a decrease in the kinetic energy of the mixed fluid M2.

The mixed fluid M2 of air-containing rice water and pre-washed rice grains, flowing through the inclined section 42a of the diffuser 42, then reaches the horizontal section 42b of the diffuser 42. Upon reaching the horizontal section 42b, the direction of flow changes to approximately horizontal.

At this point, the mixed fluid M2 of air-containing water and pre-washed rice grains reaches the horizontal section 42b, and the direction of flow changes, further reducing the kinetic energy of the mixed fluid M2.

Thus, in the diffusion step S40, the diffuser 42 can reduce the kinetic energy while changing the direction of flow of the mixed fluid M2 of air-containing rice water and pre-washed rice grains that flows approximately vertically from the opening 31a of the rice delivery pipe 31.

Then, as the direction of flow changes to approximately horizontal, the mixed fluid M2 of the rice-transmitting water containing air and pre-washed rice grains, whose kinetic energy has decreased, flows away from the outer end in the diametrical direction of the horizontal section 42b of the diffuser 42 and flows through the space inside the separator 43, reaching the inside of the drainage section 43c on the wall surface 43a of the separator 43.

In this embodiment, the action of diffusing the mixed fluid M2 of air-containing rice water and pre-washed rice grains onto the wall surface 43a of the separator 43 by the diffuser 42 in diffusion step S40 is referred to as the "first diffusion."

The shape of the diffuser 42 is merely an example; other shapes are acceptable as long as they can change the flow direction of the mixed fluid M2 of air-containing rice water and pre-washed rice grains, which flows approximately vertically from the opening 31a of the rice delivery pipe 31, to approximately horizontal. For example, the inclined portion 42a and the horizontal portion 42b of the diffuser 42 may be made into a continuous curved surface.

(5) First separation step Following the diffusion step S40, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains diffused in the diffusion step S40 is brought to the wall surface 43a of the separator 43, and the first separation step S51 is performed in which the air-containing rice water W3 and pre-washed rice grains R2 are separated by the drainage section 43c of the separator 43.

As shown in Figure 3, the first diffusion in diffusion step S40 changes the direction of flow to approximately horizontal, and the mixed fluid M2 of the supplied rice water and pre-washed rice grains, which has reduced kinetic energy, reaches the inside of the drainage section 43c on the wall surface 43a of the separator 43.

Since the drainage section 43c of the wall surface 43a of the separator 43 is provided with multiple holes 43e, the mixed fluid M2 of the supplied rice water containing air and pre-washed rice grains that reaches the inside of the drainage section 43c of the wall surface 43a of the separator 43 undergoes a "first separation" by the multiple holes 43e, separating it into pre-washed rice grains R2 and supplied rice water containing air W3.

Of the mixed fluid M2 of the air-containing rice water and pre-washed rice grains that reaches the inside of the drainage section 43c on the wall surface 43a of the separator 43, the air-containing rice water W3 flows through multiple holes 43e and outwards from the separator 43. The pre-washed rice grains R2, unable to pass through the holes 43e, remain inside the separator 43.

Thus, in the "first diffusion" of diffusion step S40, the mixed fluid M2 of air-containing rice water and pre-washed rice grains, which flows in a nearly horizontal direction, reaches the inside of the diffuser 42 in the first separation step S51. During this first separation, the mixed fluid M2 is separated into air-containing rice water W3 and pre-washed rice grains R2.

At this time, the air contained in the air-containing rice water W3 is released into the atmosphere as it flows down from the opening 31a of the rice water supply pipe 31 to the diffuser 42, causing the air to dissipate and separate from the air-containing rice water W3. Even after that, the air continues to dissipate from the air-containing rice water W3 until it reaches the diffuser 42, where it changes direction as it expands 360 degrees in a top view along its conical shape, passes through the multiple holes 43e of the separator 43, and flows to the first water receiving section 44.

Thus, the kinetic energy of the mixed fluid M2 of air-containing rice water and pre-washed rice grains is reduced twice by the diffusion step S40 until it reaches the wall surface 43a of the separator 43. This mitigates the impact when the mixed fluid M2 of air-containing rice water and pre-washed rice grains reaches the wall surface 43a of the separator 43, suppressing the cracking of the pre-washed rice grains R2 into crushed rice grains R4.

Furthermore, when the mixed fluid M2 of the air-containing rice water and pre-washed rice grains reaches the inclined section 42a or horizontal section 42b of the diffuser 42, or the wall surface 43a of the separator 43, the air contained in the air-containing rice water W3 acts as a buffer, preventing the pre-washed rice grains R2 from cracking and becoming crushed rice grains R4 due to the impact of contact.

Furthermore, the flow direction of the mixed fluid M2 of air-containing rice water and pre-washed rice grains is changed by the diffuser 42 from a nearly vertical flow when it falls from the opening 31a of the rice supply pipe 31, to a flow direction that changes upon reaching the inclined section 42a of the diffuser 42, and then to a nearly horizontal direction upon reaching the horizontal section 42b. The angle of change in the flow direction is designed to be obtuse each time.

This reduces the impact on the pre-washed rice grains R2 each time the mixed fluid M2 containing air and pre-washed rice grains changes direction, thereby preventing the pre-washed rice grains R2 from breaking and becoming crushed rice grains R4 due to the impact upon reaching the diffuser 42 and separator 43.

Furthermore, the surface of the conical diffuser 42 has no holes or other defects, allowing the mixed fluid M2 of air-containing rice water and pre-washed rice grains to flow smoothly. This also suppresses the generation of crushed rice grains R4 when the direction of flow is changed in the diffuser 42.

Furthermore, the mixed fluid M2 of air-containing rice water and pre-washed rice grains, which has been flowing downwards, is spread 360 degrees in a nearly horizontal direction by the diffuser 42, reaching a wider surface inside the drainage section 43c. In other words, the amount of mixed fluid M2 of air-containing rice water and pre-washed rice grains reaching each unit area of the drainage section 43c can be minimized. This allows for effective separation of the mixed fluid M2 of air-containing rice water and pre-washed rice grains into air-containing rice water W3 and pre-washed rice grains R2.

Then, the rice-supplied water W3 containing air, which has passed through the holes 43e in the wall surface 43a of the separator 43 and separated to the outside of the separator 43, flows to the first water receiving section 44 and then to the first return pipe 45.

The pre-washed rice grains R2, separated inside the separator 43 without passing through the holes 43e in the wall surface 43a of the separator 43, flow downwards inside the wall surface 43a of the separator 43 and then flow into the flow pipe 46.

At this point, the rice-supplying water W3, which contains air and cannot be completely separated, flows along the inside of the drainage section 43c of the wall 43a of the separator 43 along with the pre-washed rice grains R2. Although in small quantities, this water flows along the wall 43a and flows downwards toward the flow pipe 46 along with the pre-washed rice grains R2.

Furthermore, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains that reached the wall surface 43a during the first diffusion in diffusion step S40 diffuses upward and downward along the wall surface 43a. This diffusion along the wall surface 43a in both upward and downward directions is referred to as the "second diffusion." In the first separation step S51, this "second diffusion" and the separation of the air-containing rice water W3 and pre-washed rice grains R2 occur in parallel.

(6) Guidance Step Next, the guidance step S52 will be described, in which the mixed fluid M2 of the air-containing water and pre-washed rice grains that has been diffused in the diffusion step S40 reaches the wall surface 43a, and the mixed fluid M2 of the air-containing water and pre-washed rice grains that has flowed upward along the wall surface 43a is guided downward by the guidance unit 41a to lead it to the draining unit 43c.

As shown in Figure 16, this induction step S52 is performed in parallel with the first separation step S51, following the diffusion step S40.

As shown in Figure 3, the diffusion step S40 changes the direction of flow to approximately horizontal, and the mixed fluid M2 of the supplied rice water containing air and pre-washed rice grains, whose kinetic energy has decreased, reaches the inside of the drainage section 43c on the wall surface 43a of the separator 43.

At this time, in the mixed fluid M2 of the air-containing rice water and pre-washed rice grains, in addition to the air-containing rice water W3 flowing through the holes 43e and outwards from the separator 43 as a result of the first separation step S51, there is also a portion that comes into contact with the inside of the wall surface 43a (excluding the holes 43e) and flows upward along the wall surface 43a of the separator 43.

The wall surface 43a of the separator 43, the top surface 43g, the lower surface of the lid 41, and the guide section 41a attached to the lower surface of the lid 41 are configured to form a substantially continuous surface. Therefore, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains, flowing upward along the wall surface 43a of the separator 43, flows from the wall surface 43a of the separator 43 along the top surface 43g and the lower surface of the lid 41, and reaches the guide section 41a.

At this time, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains, flowing upward along the wall surface 43a of the separator 43, flows through the upper flow section 43b of the separator 43's wall surface 43a, where no holes 43e are provided. Since the air-containing rice water W3 is not separated in the upper flow section 43b, the pre-washed rice grains R2 are easily flowed by the air-containing rice water W3. This suppresses the retention of pre-washed rice grains R2 in the upper flow section 43b, while allowing the fluid to flow from the wall surface 43a of the separator 43 along the top surface 43g and the underside of the lid 41, reaching the guide section 41a.

Then, the mixed fluid M2 of air-containing rice water and pre-washed rice grains is guided downward along the guide section 41a, which extends in a substantially vertical direction, changing its flow direction. It then passes between the outer end of the horizontal section 42b of the diffuser 42 in the diametrical direction and the wall surface 43a, leading to the drain section 43c of the separator 43.

Furthermore, this prevents the mixed fluid M2 of the air-containing rice water and pre-washed rice grains, which flows upward along the wall surface 43a of the separator 43, from flowing beyond the upper end of the wall surface 43a, i.e., beyond the top surface 43g, and flowing outside the separator 43.

Furthermore, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains, which reaches the inside of the wall surface 43a excluding the hole 43e in the first separation step S51 and flows upward along the wall surface 43a of the separator 43, may flow downward along the inside of the upper flow section 43b of the wall surface 43a without reaching the guide section 41a. This also allows the mixed fluid M2 of the air-containing rice water and pre-washed rice grains to be guided to the drain section 43c of the separator 43.

At this time, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains flows through the upper flow section 43b, which does not have holes 43e. Since the air-containing rice water W3 is not separated in the upper flow section 43b, it is possible to suppress the retention of pre-washed rice grains R2 in the upper flow section 43b while allowing them to flow downward along the inside of the upper flow section 43b.

Even if pre-washed rice grains R2 remain on the inner surface of the upper flow section 43b, the inner surface of the top surface section 43g, or the surface of the guide section 41a, the mixed fluid M2 of the air-containing rice supply water and pre-washed rice grains flowing in this guide step S52 will guide it to the drain section 43c, allowing it to flow downwards so that as few pre-washed rice grains R2 as possible remain inside the separator 43.

Furthermore, even if the wall surface 43a of the separator 43 does not have an upper flow section 43b, it is acceptable if the mixed fluid M2 of the air-containing rice water and pre-washed rice grains can be guided to the drain section 43c of the separator 43 in the induction step S52 so that as little of the fluid remains as possible. In other words, the separator 43 may have a shape with multiple holes 43e extending to the upper end of the wall surface 43a.

(7) Second Separation Step Next, the second separation step S60 will be described, in which the pre-washed rice grains R2 remaining inside the separator 43 after separation in the first separation step S51 are mixed with the mixed fluid M2 of air-containing rice water and pre-washed rice grains that has been guided to the drainage section 43c by the induction step S52, and the mixed fluid M2 of air-containing rice water and pre-washed rice grains is separated into air-containing rice water W3 and pre-washed rice grains R2 by the drainage section 43c of the separator 43.

As shown in Figure 16, this second separation step S60 is performed after the first separation step S51 and induction step S52, which are performed in parallel.

In the first separation step S51, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains that reached the inside of the drainage section 43c of the wall surface 43a of the separator 43 by the diffusion step S40 diffuses upward and downward along the wall surface 43a by the "second diffusion." Of this, some of the mixed fluid M2 of the air-containing rice water and pre-washed rice grains that diffuses downward remains inside the drainage section 43c, and the remaining pre-washed rice grains R2 stay there.

Furthermore, in the first separation step S51, the mixed fluid M2 of the air-containing rice water and pre-washed rice grains, which reached the inside of the drainage section 43c on the wall surface 43a of the separator 43 shown in Figure 3 by the diffusion step S40, was separated into the inside and outside of the separator 43 by multiple holes 43e. Because the pre-washed rice grains R2 separated from the air-containing rice water W3 have weaker flowing force, some of the pre-washed rice grains R2 that remain inside the separator 43 also remain inside the drainage section 43c.

In addition, in the induction step S52, the mixed fluid M2 of the rice-supplying water containing air and pre-washed rice grains, which flows upward with weak momentum, does not reach the induction section 41a but flows downward along the inside of the upper flow section 43b of the wall surface 43a towards the drain section 43c. However, because the downward flow momentum is also weak, it may remain inside the drain section 43c, leaving behind pre-washed rice grains R2.

The remaining pre-washed rice grains R2, which stay inside the drainage section 43c, are then mixed with the mixed fluid M2 of the air-containing rice-transporting water and pre-washed rice grains, which was guided to the drainage section 43c by the induction step S52.

The mixed fluid M2 of the air-containing rice delivery water and pre-washed rice grains flows downward inside the drainage section 43c, and is separated into the air-containing rice delivery water W3 and the pre-washed rice grains R2 by the multiple holes 43e. In this way, the pre-washed rice grains R2 that remain inside the drainage section 43c during the first separation step S51 are guided to the drainage section 43c in the induction step S52, where the mixed fluid M2 of air-containing rice delivery water and pre-washed rice grains flows downward along the drainage section 43c, separating into the air-containing rice delivery water W3 and the pre-washed rice grains R2.

This effectively separates the mixed fluid M2 of air-containing rice water and pre-washed rice grains, which has flowed almost vertically into the separator 43, into air-containing rice water W3 and pre-washed rice grains R2 through the first separation step S51 and the second separation step S60. Furthermore, it minimizes the amount of pre-washed rice grains R2 remaining inside the drainage section 43c of the separator 43.

In particular, because the holes 43e in the wall surface 43a of this invention are elongated holes inclined with respect to the horizontal direction, the downward flow of pre-washed rice grains R2 is easily obstructed inside the drainage section 43c, and the pre-washed rice grains R2 tend to remain inside the wall surface 43a. The second separation step S60 effectively separates the pre-washed rice grains R2 from the air-containing rice-transmitting water W3, while simultaneously reducing the amount of pre-washed rice grains R2 remaining inside the separator 43 as much as possible.

The air-containing rice water W3, separated to the outside of the separator 43 through the multiple holes 43e, flows to the first water receiving section 44 and then to the first return pipe 45. The pre-washed rice grains R2, separated to the inside of the separator 43 through the multiple holes 43e, flow downwards and reach the lower flow section 43d of the separator 43.

The shape of the separator 43 is not limited to that exemplified in this embodiment. For example, the separator 43 may be a flat plate-shaped member, in which case the same effects can be achieved by providing a drainage section 43c and a downward flow section 43d on the flat plate-shaped wall surface 43a as shown in Figure 3.

(8) Flowing Step Next, the flowing step S70 will be described, in which the pre-washed rice grains R2 separated in the first separation step S51 and the second separation step S60 are allowed to fall and flow downward, and the pre-washed rice grains R2 separated on the inside of the wall surface 43a are allowed to flow downward with the air-containing rice water W3 that could not be separated from the mixed fluid M2 of air-containing rice water and pre-washed rice grains in the first separation step S51 and the second separation step S60.

The pre-washed rice grains R2 separated to the inside of the wall surface 43a of the separator 43 by the first separation step S51 and the second separation step S60 flow downward through the inside of the drainage section 43c and reach the lower flow section 43d of the wall surface 43a.

Since the lower flow section 43d does not have holes 43e, the air-containing rice water W3 that could not be completely separated from the mixed fluid M2 of air-containing rice water and pre-washed rice grains in the first separation step S51 and the second separation step S60 allows the pre-washed rice grains R2 to flow smoothly downward towards the flow pipe 46.

Furthermore, the force of the mixed fluid M2 of air-containing rice water and pre-washed rice grains, whose flow direction has been changed downward by the guiding section 41a in the guiding step S52, allows the pre-washed rice grains R2 to flow smoothly downward towards the flow pipe 46.

Furthermore, even if pre-washed rice grains R2 remain on the inner surface of the lower flow section 43d, as already described in the flow step S70, the air-containing rice supply water W3 flowing downwards can smoothly move the remaining pre-washed rice grains R2 in the lower flow section 43d downwards towards the flow pipe 46.

Furthermore, before the completion of the first separation step S51 and the second separation step S60, the following crushed rice grains R4 may mix with the mixed fluid M2 of the air-containing rice supply water and the washed rice grains.
(1) The broken rice grains R4 that were originally broken were supplied in the supply step S20.
(2) In the supply step S20, the crushed rice grains R4 are generated by the impact when supplied to the introduction guide 21.
(3) In the rice washing step S30, when the rice is flowed through the rice supply pipe 31 and the rice washing means 32, crushed rice grains R4
(4) In the diffusion step S40, when the mixed fluid M2 of the air-containing rice water and the washed rice grains reaches the diffuser 42, crushed rice grains R4 are generated.
(5) In the first separation step S51, when the mixed fluid M2 of the air-containing rice water and the washed rice grains reaches the wall surface 43a of the separator 43, crushed rice grains R4 are generated.
(6) In the induction step S52, the flow direction is changed downward by the induction section 41a and the crushed rice grains R4 are generated when they are guided to the drain section 43c.

Most of the crushed rice grains R4 from (1) to (6) pass through the multiple holes 43e of the separator 43 when the mixed fluid M2 of air-containing rice water and pre-washed rice grains reaches the wall 43a of the separator 43, and flow into the first return pipe 45 together with the air-containing rice water W3. The crushed rice grains R4 that did not pass through the multiple holes 43e of the separator 43 flow into the fluid pipe 46 together with the pre-washed rice grains R2 and the air-containing rice water W3.

Furthermore, because the multiple holes 43e in the wall surface 43a of the separator 43 are elongated holes inclined with respect to the horizontal, the air-containing rice water W3 flowing along the inside of the wall surface 43a of the separator 43, together with the pre-washed rice grains R2, flows in a swirling motion along the inside of the wall surface 43a of the separator 43.

Furthermore, compared to flowing linearly downwards along the inside of the wall surface 43a of the separator 43, the mixed fluid M2 of air-containing rice water and pre-washed rice grains can flow along the inside of the wall surface 43a, which has multiple holes 43e, for a longer period of time. This allows for more effective separation of the mixed fluid M2 of air-containing rice water and pre-washed rice grains into air-containing rice water W3 and pre-washed rice grains R2.

As a result, in separation steps S51 and S60, without requiring power from a drive mechanism or the like, the cracking of the pre-washed rice grains R2 can be suppressed, and almost the entire amount of pre-washed rice grains R2 washed in step S30 can be sent to the immersion section 60 for the next step.

Furthermore, assuming that some pre-washed rice grains R2 remain on the upper surface of the diffuser 42 and inside the wall surface 43a of the separator 43 after the flow step S70 and before moving to the immersion step S80, after the flow step S70, the supply of polished rice grains R1 to the introduction guide 21 of the rice washing section 20 shown in Figure 1 may be temporarily stopped, and only the rice supply water W3 containing air may be allowed to flow from the rice supply pipe 31 to the diffuser 42 and separator 43. This ensures that the pre-washed rice grains R2 that have flowed out of the rice washing section 20 are allowed to flow into the immersion section 60.

In this embodiment, the direction of flow of the mixed fluid M2, which consists of air-containing rice water and pre-washed rice grains, is changed multiple times (twice) as it flows substantially vertically from the opening 31a of the rice delivery pipe 31. Each time, the kinetic energy is reduced, allowing the fluid to reach the inside of the wall 43a of the separator 43. However, by changing the shape of the diffuser 42, the number of times the direction of flow of the mixed fluid M2, consisting of air-containing rice water and pre-washed rice grains, is changed may be three or more.

For example, the surface of the inclined portion 42a of the diffuser 42 may be embossed or otherwise modified to create irregularities, thereby reducing the kinetic energy of the mixed fluid M2 of air-containing rice water and pre-washed rice grains flowing through the inclined portion 42a. Alternatively, a member for changing the flow direction of the mixed fluid M2 of air-containing rice water and pre-washed rice grains, such as a flow direction changing member made of sheet metal, may be provided below the conical diffuser 42 to change the flow direction and further reduce kinetic energy.

This allows the kinetic energy of the mixed fluid M2 containing air-entrained rice water and pre-washed rice grains to be more effectively reduced, enabling it to reach the wall surface 43a of the separator 43, thereby suppressing the generation of crushed rice grains R4.

(9) Immersion step After the separation steps S51 and S60 are completed, the washed rice grains R2 separated in the separation steps S51 and S60 are immersed in the immersion water W4 stored in the immersion tank 61, and the immersion step S80 is performed to cause the rice bran foam floating on the surface of the immersion water W4 to flow out along with the immersion water W4 stored in the immersion tank 61, causing an overflow.

As shown in Figure 11, the pre-washed rice grains R2, separated from the mixed fluid M2 of the air-containing rice water and pre-washed rice grains in separation steps S51 and S60, flow through the flow pipe 46 to the immersion tank 61 via the opening 46a. Furthermore, although not shown in Figure 11, the air-containing rice water W3 that was not separated to the first water receiving section 44 also flows through the flow pipe 46 to the immersion tank 61 via the opening 46a.

The pre-washed rice grains R2 and the air-containing rice-supplying water W3 fall and flow onto the surface of the soaking water W4 stored in the soaking tank 61, and the pre-washed rice grains R2 are stored as soaked rice grains R3 within the soaking water W4. Then, when the soaking water W4 is filled to the full water level H3 in the soaking tank 61, the water level rises above H3 by the volume of the falling pre-washed rice grains R2 and the air-containing rice-supplying water W3.

Then, the immersion water W4 stored in the immersion tank 61 flows over the upper end of the wall 76a of the overflow section 76 and overflows into the overflow section 76. The immersion water W4 that overflows into the overflow section 76 flows into the opening 77a of the second return pipe 77 and flows downwards within the second return pipe 77.

The rice grains R3, which fall into the immersion water W4 stored in the immersion tank 61 up to the full water level H3, flow in the direction indicated by the arrows in Figure 11 and reach the guide plate 64. Upon reaching the guide plate 64, the rice grains R3 flow in the direction indicated by the arrows, that is, from the upper surface of the inclined guide plate 64, through the gap between the conical outer edge of the guide plate 64 and the wall of the immersion tank 61, along the inside of the wall of the immersion tank 61, and flow through the flow opening 61a into the pipe 78. Since the rice distribution valve 79 in the pipe 78 is closed, the rice grains R3 are stored in the immersion tank 61.

As shown in Figure 12, the soaked rice grains R3 are stored in the soaking tank 61 and accumulate in a mountain-like shape formed at the angle of repose θ1. Eventually, the soaked rice grains R3 stored in the soaking tank 61 in a mountain-like shape come into contact with the lower end of the movable compartment member 73. The soaked rice grains R3 stored outside the area enclosed by the fixed compartment member 72 and the closed movable compartment member 73 form a ridge line 80a.

As the pre-washed rice grains R2 continue to fall and flow into the immersion tank 61, the immersed rice grains R3 are stored in the area enclosed by the fixed compartment member 72 and the movable compartment member 73, forming a ridge line 80b. This ridge line 80b is located above the line extending from the side of the ridge line 80a of the immersed rice grains R3 that is in contact with the lower end of the movable compartment member 73 toward the flow pipe 46.

The soaked rice grains R3 stored within the area enclosed by the fixed compartment member 72 and the movable compartment member 73 are retained until a mass sufficient to cause the movable compartment member 73 to open outwards from the soaking tank 61 is applied to it.

Until enough mass is applied to the movable compartment member 73 to open it outward from the immersion tank 61, the immersed rice grains R3 stored inside the area enclosed by the fixed compartment member 72 and the movable compartment member 73 flow outward from the compartment area 75 through the gap between the notch 72c of the fixed compartment member 72 and the movable compartment member 73. Then, as the pre-washed rice grains R2 continue to fall and flow into the immersion tank 61, the movable compartment member 73 gradually opens outward from the immersion tank 61.

When the movable compartment member 73 opens outward, the notch 72c provided in the fixed compartment member 72 allows the soaked rice grains R3 to gradually flow outward from the area enclosed by the fixed compartment member 72 and the movable compartment member 73. This stabilizes the pile of soaked rice grains R3 stored at the angle of repose θ1 outside the compartment area 75, while allowing the soaked rice grains R3 within the compartment area 75 to flow outward.

Furthermore, the gap between the notch 72c of the fixed partition member 72 and the movable partition member 73 allows the soaked rice grains R3 to flow outward from the partition area 75. This gently breaks down the pile of soaked rice grains R3 that have accumulated to form a ridge 80b, guiding the accumulated soaked rice grains R3 to flow outward from the partition area 75. This guidance, in turn, promotes the opening of the movable partition member 73 outward.

When a predetermined amount of soaked rice grains R3 is stored in the soaking tank 61, each movable compartment member 73 rotates by a predetermined angle θ3, for example, approximately 10 degrees, towards the outside of the soaking tank 61, using the axis of the hinge 74 as the axis of rotation. As a result, the soaked rice grains R3 stored in the area enclosed by the fixed compartment member 72 and the movable compartment member 73 flow outwards from that area, and are stored in a mountain-like shape within the soaking tank 61, forming a ridge 80 between the area enclosed by the fixed compartment member 72 and the movable compartment member 73 and the area outside that area.

Then, by gradually allowing the soaked rice grains R3 to flow outwards from the area enclosed by the fixed compartment member 72 and the movable compartment member 73, and by opening the movable compartment member 73 to the outside of the soaking tank 61, the soaked rice grains R3 can be stored stably, and a larger amount of soaked rice grains R3 can be stored in the soaking tank 61.

Furthermore, as shown in Figure 11, the hinge 74 is configured to be located below the water level H3 of the immersion water W4 stored in the immersion tank 61. This allows the rice bran foam, which floats on the surface of the immersion water W4 (described later), to remain within the compartment 75 even when the movable compartment member 73 rotates outward by a predetermined angle θ3.

Furthermore, when the ridge line 80 of the piled-up soaked rice grains R3 reaches the storage amount detection means 70, the storage amount detection means 70 detects that the amount of soaked rice grains R3 stored in the soaking tank 61 is a predetermined amount. Then, an electrical signal is sent from the storage amount detection means 70 to the control panel 141, and a lamp or other indicator attached to the control panel 141 informs the operator that the predetermined amount of soaked rice grains R3 has been stored in the soaking tank 61.

The operator supplying polished rice grains R1 to the introduction guide section 21 stops supplying polished rice grains R1 when they see a lamp or other indicator on the control panel 141 indicating that a predetermined amount of soaked rice grains R3 has been stored in the soaking tank 61. In other words, supply step S20 stops when the amount of soaked rice grains R3 stored in the soaking tank 61 reaches a predetermined level.

The soaked rice grains R3 stored in the soaking tank 61 are soaked in the soaking water W4 stored in the soaking tank 61 for a predetermined time, for example, 30 to 90 minutes.

Furthermore, the operator may voluntarily stop supplying polished rice grains R1 before the amount of soaked rice grains R3 stored in the soaking tank 61 reaches a predetermined amount. In this case, the predetermined amount of soaked rice grains R3 will not be stored in the soaking tank 61, but the supply amount of polished rice grains R1 may be controlled according to a predetermined amount of cooked rice. Also, when the rice distribution step S90 described later is started and the soaked rice grains R3 stored in the soaking tank 61 flow to the rice distribution unit 90, and the amount of soaked rice grains R3 stored in the soaking tank 61 decreases, the supply step S20 may be performed again.

Furthermore, if the supply step S20 is configured to automatically supply polished rice grains R1 to the introduction guide 21 shown in Figure 1, the storage amount detection means 70 may control the system to stop the operation of the meter and rice lifter and stop the supply of polished rice grains R1 when it detects that the amount of soaked rice grains R3 stored in the soaking tank 61 is a predetermined amount.

Next, we will explain in detail what happens when the washed rice grains R2 are dropped and flowed into the soaking water W4, which is filled to a water level H3 in the soaking tank 61, and the washed rice grains R2 hit the soaking water W4.

In the rice washing section 20 shown in Figure 1, when polished rice grains R1 are washed by the rice washing means 32, the rice bran attached to the polished rice grains R1 separates from the grains R1 and mixes with the air-containing rice supply water W3. The washed rice grains R2, having finished washing by the rice washing means 32, then flow to the separation section 40 as a mixed fluid M2 of the air-containing rice supply water and the washed rice grains. This air-containing rice supply water W3 contains the rice bran that was attached to the polished rice grains R1. The surface of the washed rice grains R2 separated in the separation section 40 is then covered with this air-containing rice supply water W3 mixed with rice bran.

The pre-washed rice grains R2, to which air-containing rice bran-infused water W3 has adhered, land on the surface of the soaking water W4 stored in the soaking tank 61 up to the full water level H3, entraining air as it falls. At this time, the rice bran contained in the air-infused rice bran-infused water W3 that was adhering to the surface of the pre-washed rice grains R2 mixes with the air and soaking water W4, forming rice bran foam. This rice bran foam spreads over the surface of the soaking water W4 stored in the soaking tank 61, sinks to a predetermined depth from the water level H3, and then floats back up to the surface.

As shown in Figure 11, the lower ends of the fixed compartment member 72 and the movable compartment member 73 are positioned vertically downward at a distance H5 from the water level H3 when the immersion tank 61 is full. Furthermore, both ends of the fixed compartment member 72 are configured to be substantially in contact with the inside of the wall surface of the immersion tank 61.

Therefore, even if pre-washed rice grains R2 land on the surface of the soaking water W4 stored in the soaking tank 61, and rice bran foam generated by the rice bran adhering to the pre-washed rice grains R2 spreads over the surface of the soaking water W4 stored in the soaking tank 61, the fixed partition member 72, which extends vertically upward from the surface of the soaking water W4 stored in the soaking tank 61, can contain the rice bran foam within the partitioned area 75, preventing it from flowing outside the partitioned area 75.

Furthermore, even if the rice bran foam sinks to a predetermined depth from the surface of the immersion water W4 at water level H3 and then floats back up to the surface, the lower ends of the fixed compartment member 72 and the movable compartment member 73 are positioned below the depth to which the rice bran foam sinks from the water surface. In other words, the fixed compartment member 72 and the movable compartment member 73, which extend vertically downward to a distance H5 from the surface of the immersion water W4 stored in the immersion tank 61, prevent the rice bran foam from flowing outside the compartment area 75 by passing beneath the fixed compartment member 72 and the movable compartment member 73.

Then, within the partitioned area 75, which is separated by the fixed partition member 72 and the inner wall of the immersion tank 61, the rice bran foam rises and spreads on the water surface. This allows the rice bran foam generated when the washed rice grains R2 come into contact with the immersion water W4 stored in the immersion tank 61 to be kept within the partitioned area 75, enabling the immersion tank 61 to be used cleanly without contaminating the area outside the partitioned area 75 as much as possible.

Furthermore, when pre-washed rice grains R2 fall into the immersion water W4, which has been filled to the full water level H3 in the immersion tank 61, and are stored as immersed rice grains R3, the water level rises above H3 by the volume of the fallen pre-washed rice grains R2. Then, the immersion water W4 stored in the immersion tank 61 flows over the upper end of the wall 76a of the overflow section 76, along with the rice bran foam floating in the compartment 75, and overflows into the overflow section 76. The immersion water W4 and rice bran foam that overflow into the overflow section 76 flow into the opening 77a of the second return pipe 77 and flow downwards within the second return pipe 77.

This allows the rice bran foam floating in the compartment 75 of the immersion water W4 stored in the immersion tank 61 to overflow into the overflow section 76 along with the immersion water W4, without the need to use equipment such as a pump to provide power. This allows the rice bran to be discharged as rice bran foam from the immersion water W4 stored in the immersion tank 61, thereby purifying the immersion water W4.

Furthermore, the kinetic energy of the pre-washed rice grains R2 as they fall and flow onto the surface of the immersion water W4 is reduced not only by the diffusion step S40 described above, but also by the change in flow direction during the first separation step S51, the induction step S52, and the second separation step S60. Therefore, compared to the case where the kinetic energy of the pre-washed rice grains R2 as they fall is not reduced by the diffuser 42, the impact when the pre-washed rice grains R2 hit the surface of the immersion water W4 is smaller.

This prevents the pre-washed rice grains R2 from breaking when they hit the surface of the soaking water W4 stored in the soaking tank 61. Furthermore, after the pre-washed rice grains R2 hit the surface of the soaking water W4, which is filled to the maximum water level H3 in the soaking tank 61, the depth to which the rice bran foam sinks into the soaking water W4 is reduced. The fixed partition member 72 and the movable partition member 73 ensure that the rice bran foam floating on the surface of the soaking water W4 stored in the soaking tank 61 is reliably contained within the partitioned area 75.

Furthermore, the distance H5 between the lower ends of the fixed compartment member 72 and the movable compartment member 73 and the water level H3 of the immersion water W4 can be reduced, thereby allowing the fixed compartment member 72 and the movable compartment member 73 to be miniaturized.

Furthermore, by reducing the kinetic energy of the pre-washed rice grains R2 when they hit the soaking water W4 stored in the soaking tank 61, the amount of air that the pre-washed rice grains R2 entrain when they hit the surface of the soaking water W4 is reduced. This reduces the amount of rice bran foam generated at the surface of the soaking water W4 stored in the soaking tank 61, where air and rice bran mix.

In addition, when the pre-washed rice grains R2 enter the immersion water W4 stored in the immersion tank 61, the opening 46a of the flow pipe 46 is located at a distance H4 below the water level H3 of the immersion water W4 stored in the immersion tank 61 until it is full. Furthermore, a water surface of immersion water W4 at the same level as water level H3 is formed inside the flow pipe 46.

This ensures that the pre-washed rice grains R2 only strike the immersion water W4 and entrain air at its surface within the fluidized pipe 46. Compared to the case where the opening 46a of the fluidized pipe 46 is positioned above the water surface H3, this reduces the amount of rice bran foam generated when the pre-washed rice grains R2 strike the immersion water W4.

The rice bran foam generated by the mixing of air and rice bran comes into contact with the fixed compartment member 72, the movable compartment member 73, and the inside of the walls of the immersion tank 61, causing the rice bran to adhere to the surfaces of these members. If the rice bran foam adheres to areas that have little contact with the clean water W1 sprayed from the water supply nozzle 68 or the immersion water W4 stored in the immersion tank 61, it tends to dry out over time, becoming difficult to wash away with the clean water W1.

Furthermore, if mold or other contaminants develop on the rice bran adhering to the fixed compartment member 72, the movable compartment member 73, or the inner walls of the immersion tank 61, these contaminants may detach and mix with the immersed rice grains R3. They may then be supplied to the rice cooker 97 via the rice distribution step S90 (described later), potentially contaminating the cooked rice as foreign matter.

This risk can be suppressed by reducing the generation of rice bran foam when the pre-washed rice grains R2 land on the surface of the soaking water W4.

Furthermore, the opening 46a of the flow pipe 46 may be located above the water level H3 of the immersion water W4 stored in the immersion tank 61 until it is full. In this case, when the pre-washed rice grains R2 falling and flowing through the flow pipe 46 hit the surface of the immersion water W4, a large amount of rice bran foam can be generated on the surface of the immersion water W4 stored in the immersion tank 61.

Furthermore, when the water level of the immersion water W4 stored in the immersion tank 61 rises above the upper end of the wall 76a of the overflow section 76, the large amount of rice bran foam floating on the surface of the immersion water W4 stored in the immersion tank 61 can be more effectively circulated along with the immersion water W4, causing it to overflow beyond the wall 76a into the overflow section 76.

As described above, the effects produced vary depending on the height position of the opening 46a of the fluidizing pipe 46. The height position of the opening 46a of the fluidizing pipe 46 should be appropriately set depending on the type of polished rice grains R1 being washed. Alternatively, a vertically movable member may be provided at the opening 46a of the fluidizing pipe 46, allowing the position of the opening 46a to be varied according to the type of polished rice grains R1 being washed.

Next, we will describe in detail the state of the compartmentalized area 75 of the immersion water W4 stored in the immersion tank 61 when the pre-washed rice grains R2 are stored in the immersion tank 61.

As shown in Figure 8, when the pre-washed rice grains R2 and the supplied rice water W3 containing air begin to flow into the immersion water W4 stored in the immersion tank 61 up to the full water level H3, the water level of the immersion water W4 rises above the water level H3 by the volume of the pre-washed rice grains R2 and the supplied rice water W3 that have flowed into the immersion tank 61. As a result, the water level of the immersion water W4 becomes above the upper end of the wall 76a of the overflow section 76, and the immersion water W4 stored in the immersion tank 61 overflows the wall 76a into the overflow section 76.

This allows the pre-washed rice grains R2 and the air-containing rice water W3 to fall and flow into the immersion water W4 stored in the immersion tank 61. The rice bran attached to the pre-washed rice grains R2 floats as rice bran foam within the compartment 75, overflowing and being discharged along with the immersion water W4 into the overflow section 76. This allows the immersion tank 61 to be used as cleanly as possible. Furthermore, it suppresses the decrease in the cleanliness of the immersion water W4 stored in the immersion tank 61.

Then, as the flow of pre-washed rice grains R2 into the soaking water W4 stored in the soaking tank 61 continues, the amount of soaked rice grains R3 stored in the soaking tank 61 reaches a predetermined amount. When the amount of soaked rice grains R3 stored in the soaking tank 61 reaches the predetermined amount, the operator stops supplying polished rice grains R1 to the introduction guide 21 of the rice washing unit 20, and consequently, the flow of pre-washed rice grains R2 into the soaking tank 61 also stops.

When the amount of soaked rice grains R3 stored in the soaking tank 61 reaches a predetermined amount, the storage amount detection means 70 will come into contact with the ridge 80 of the pile of soaked rice grains R3 stored in the soaking tank 61. The storage amount detection means 70 then detects that a predetermined amount of soaked rice grains R3 has been stored in the soaking tank 61 and sends an electrical signal to the control panel 141. Upon receiving this electrical signal, the control panel 141 opens the valve 67 of the water supply pipe 66 and sprays clean water W1 from the water supply nozzle 68 for a predetermined time, for example, 10 seconds.

As shown in Figure 6, even if the falling flow of the pre-washed rice grains R2 stops, by spraying clean water W1 from the water supply nozzle 68 for a predetermined time, the rice bran foam floating in the compartment 75 continues to flow together with the immersion water W4, overflowing into the overflow section 76 and being discharged. This reduces the amount of rice bran foam floating in the compartment 75, allowing the immersion tank 61 to be used cleanly. Furthermore, the mixing of clean water W1 with the immersion water W4 suppresses a decrease in the cleanliness of the immersion water W4 stored in the immersion tank 61.

Furthermore, two water supply nozzles 68 are provided, facing approximately the same direction. One is configured to spray clean water W1 downwards from the horizontal at a predetermined angle, for example, 20 degrees, while the other is configured to spray clean water W1 approximately horizontally.

Furthermore, by injecting clean water W1 from one water supply nozzle 68, the flow of rice bran foam floating within the compartment 75 towards the overflow section 76 can be promoted. Additionally, by injecting clean water W1 from the other water supply nozzle 68, the flow of rice bran foam floating within the compartment 75 closer to the overflow section 76 than where the clean water W1 injected from one water supply nozzle 68 lands can be promoted towards the overflow section 76.

Then, the immersion water W4 that overflows beyond the wall section 76a into the overflow section 76 flows into the second return pipe 77 along with the rice bran foam.

The angle at which the water supply nozzles 68 spray the clean water W1 may be different from the angle exemplified. For example, one nozzle may be configured to spray the clean water W1 at a predetermined angle downward from the horizontal, for example, 60 degrees downward from the horizontal, while the other nozzle may be configured to spray the clean water W1 at a predetermined angle downward from the horizontal, for example, 30 degrees downward from the horizontal. Alternatively, the angle at which one water supply nozzle 68 sprays the clean water W1 may be the same as the angle at which the other water supply nozzle 68 sprays the clean water W1.

Furthermore, the number of water supply nozzles 68 may be increased or decreased. For example, one water supply nozzle 68 may be provided that sprays clean water W1 over a width equal to or greater than the width sprayed by two water supply nozzles 68. Alternatively, three or more water supply nozzles 68 may be provided.

Furthermore, although the water supply nozzle 68 is positioned opposite the overflow section 76, it may be positioned in a different location. For example, it may be positioned above the frame 71 or above the overflow section 76. As long as the water supply nozzle 68 can inject clean water W1 to promote the flow of rice bran foam floating in the compartment 75 towards the overflow section 76, it may be positioned and oriented in any direction.

(10) Rice distribution step After the soaking step S80 is completed, the rice distribution step S90 is performed in which the soaked rice grains R3 that were soaked in the soaking step S80 are supplied in a predetermined amount to the rice cooker pot 97 by the rice distribution unit 90.

The soaked rice grains R3, which have been immersed in the soaking tank 61 of the soaking section 60 shown in Figure 1 for a predetermined time and absorbed water, will then flow through the soaking water W4 and the soaked rice grains R3 into the separate rice distribution container 92 by opening the rice distribution valve 79 provided in the piping 78 of the soaking section 60 for a predetermined time, for example, 3 seconds.

As shown in Figures 13 and 14, the soaked rice grains R3 stored in the soaking tank 61 are guided by the slanted edge of the upper surface of a guide plate 64 located below the soaking tank 61, and flow through the gap formed between the outer edge of the guide plate 64 and the wall surface of the soaking tank 61 to the flow opening 61a. This allows the upper surface of the guide plate 64 to support the mass of the soaked rice grains R3 stored in the soaking tank 61.

Furthermore, by preventing the mass of the soaked rice grains R3 stored above the guide plate 64 from acting on the soaked rice grains R3 flowing into the flow opening 61a, the soaked rice grains R3 stored in the soaking tank 61 can be smoothly flowed into the flow opening 61a. Additionally, the soaked rice grains R3 that have already fallen and been soaked from the separation unit 40 can be flowed to the rice distribution unit 90 first, thereby suppressing variations in the soaking time of the soaked rice grains R3 supplied to the rice cooker 97 in the rice distribution unit 90.

Furthermore, the angle θ2 of the hypotenuse of the guide plate 64 relative to the horizontal is set to be smaller than the angle of repose θ1. Therefore, while the soaked rice grains R3 stored in the soaking tank 61 are flowing down from the flow opening 61a through the piping 78 to the separated rice distribution container 92, the ridge line 80 of the soaked rice grains R3 stored in the soaking tank 61 maintains the angle of repose θ1. This stabilizes the flow of the soaked rice grains R3 stored in the soaking tank 61 to the piping 78 and prevents clogging of the soaked rice grains R3 at the flow opening 61a.

When the rice distribution valve 79 is opened, the soaked rice grains R3 stored in the soaking tank 61 are sent to the separate rice distribution container 92 via the piping 78. Along with the soaked rice grains R3, the soaking water W4 also flows to the separate rice distribution container 92 via the piping 78. When the water level of the soaking water W4 stored in the soaking tank 61 falls below the water level H3, this is detected by the water level detection means 69, which then sends an electrical signal to the control panel 141.

Then, the control panel 141, having received the electrical signal, sends an electrical signal to the valve 67, opening the valve 67 and injecting clean water W1 into the immersion tank 61 from the water supply nozzle 68 through the water supply pipe 66 of the immersion section 60 until the immersion water W4 stored in the immersion tank 61 reaches the full water level H3.

When the immersion water W4 stored in the immersion tank 61 reaches the full water level H3, the water level detection means 69 detects the water level of the immersion water W4 and closes the valve 67. At this time, considering the effect of water level fluctuations due to ripples on the surface of the immersion water W4 stored in the immersion tank 61, the control unit 140 controls the system so that when the water level detection means 69 detects that the immersion water W4 is at the full water level H3 for a predetermined time, for example, 3 to 10 seconds, it determines that the water level of the immersion water W4 is at water level H3.

In other words, each time the rice distribution valve 79 is opened and the soaking water W4 stored in the soaking tank 61 and the soaked rice grains R3 stored in the soaking tank 61 are sent to the separate rice distribution container 92, the water level of the soaking water W4 stored in the soaking tank 61 decreases.

Whenever the water level of the immersion water W4 stored in the immersion tank 61 drops, the water level detection means 69 detects the water level of the immersion water W4 stored in the immersion tank 61, opens the valve 67, and sprays clean water W1 from the water supply nozzle 68 through the water supply pipe 66 into the immersion tank 61 until the water level of the immersion water W4 stored in the immersion tank 61 reaches the full water level H3.

Furthermore, when the control unit 140 detects that the immersion water W4 stored in the immersion tank 61 is at the water level H3 for a predetermined period of time, the predetermined time until the control unit 140 determines that the immersion water W4 is at the water level H3 may be longer than the time exemplified. By extending the predetermined time, clean water W1 will be sprayed from the water supply nozzle 68 into the immersion tank 61 for a longer period.

This allows the water level of the immersion water W4 stored in the immersion tank 61 to rise, causing the immersion water W4 to overflow beyond the upper end of the wall 76a of the overflow section 76 into the overflow section 76. This allows the rice bran foam floating in the compartment 75 to flow along with the immersion water W4 and overflow into the overflow section 76. Furthermore, this reduces the amount of rice bran foam floating in the compartment 75, and the mixing of clean water W1 with the immersion water W4 suppresses a decrease in the cleanliness of the immersion water W4 stored in the immersion tank 61.

Then, continuing the rice distribution step S90, as the soaking water W4 and soaked rice grains R3 stored in the soaking tank 61 flow down through the piping 78 to the separated rice distribution container 92, the ridge line 80 that was in contact with the movable compartment member 73 of the soaked rice grains R3 stored in the soaking tank 61 moves downward. As the ridge line 80 moves downward, the lower end of the movable compartment member 73 that was in contact with the ridge line 80 also moves downward, causing the movable compartment member 73, which was open at an angle θ3, to rotate around the axis of the hinge 74 and close.

As shown in Figure 14, by opening the rice distribution valve 79 for a predetermined time, the soaking water and soaked rice grains M3 flow from the flow opening 61a of the soaking tank 61 through the piping 78 to the separated rice distribution container 92.

Of the soaking water and soaking rice grains M3 that fall into the separated rice container 92, the soaking water W4 flows through multiple holes 92a (not shown) in the wall of the separated rice container 92 to the second water receiving section 93. The soaking water W4 that flows into the second water receiving section 93 is then drained through the drain pipe 94.

Of the soaking water and soaked rice grains M3 that fall into the separate rice distribution container 92, the soaked rice grains R3 are stored in the separate rice distribution container 92 in a predetermined amount by adjusting the rice distribution amount regulator 91 in the preparation step S10. Then, after a predetermined time has elapsed for the rice distribution valve 79 to be opened, the rice distribution valve 79 is closed.

After the rice distribution valve 79 is closed, the drive mechanism 96 drives the shutter 95 to open the lower opening of the rice separation container 92, supplying a predetermined amount of soaked rice grains R3 stored in the rice separation container 92 to the rice cooker 97.

Furthermore, by repeating the rice distribution step S90, when the soaking water W4 and soaked rice grains R3 stored in the soaking tank 61 shown in Figure 13 are allowed to flow into the rice distribution section 90, the water level of the soaking water W4 stored in the soaking tank 61 fluctuates.

Due to these fluctuations, the lower ends of the fixed compartment member 72 and the movable compartment member 73 are positioned below the lowest water level of the immersion water W4. Furthermore, both horizontal ends of the fixed compartment member 72 are configured to be substantially in contact with the inside of the wall surface of the immersion tank 61. Additionally, the hinge 74 attached to the fixed compartment member 72 is also positioned below the lowest water level of the immersion water W4 stored in the immersion tank 61.

This allows the soaking water W4 and soaked rice grains R3 stored in the soaking tank 61 to flow into the rice distribution section 90. Even if the water level of the soaking water W4 in the soaking tank 61 fluctuates, the rice bran foam floating within the compartment 75 of the soaking water W4 stored in the soaking tank 61 can be retained within the compartment 75.

The temporarily lowered water level in the immersion tank 61 is detected by the water level detection means 69. The control panel 141 opens the valve 67, and clean water W1 is injected into the immersion tank 61 from the water supply nozzle 68 through the water supply pipe 66 until the immersion water W4 stored in the tank reaches the full water level H3.

This increases the amount of soaking water W4 stored in the soaking tank 61 while maintaining the same amount of rice bran floating in the soaking water W4, thereby reducing the proportion of rice bran in the soaking water W4 used to soak the rice grains R3. Since the rice grains R3 can be soaked in cleaner soaking water W4, the resulting rice, cooked by heating the rice cooker pot 97 (which contains the soaked rice grains R3 and cooking water W6 and has a lid described later), is less likely to develop a bran-like odor.

Furthermore, the soaking water W4 separated from the soaked rice grains R3 and flowing from the second water receiving section 93 may not be drained through the drain pipe 94, but instead flow into the first purification tank 121 of the purification section 120, which will be described later. This allows for a greater reduction in the amount of water used for washing the rice.

Furthermore, when the rice distribution valve 79 is opened for a predetermined time, allowing the soaking water and soaked rice grains M3 to flow from the soaking tank 61 through the piping 78 to the separate rice distribution container 92, and when clean water W1 is sprayed from the water supply nozzle 68 for a predetermined time, the amount of clean water W1 sprayed from the water supply nozzle 68 may be greater than the amount of soaking water and soaked rice grains M3 that flows from the soaking tank 61 to the separate rice distribution container 92 in one rice distribution step S90. This ensures that the rice bran foam, along with the soaking water W4, is reliably overflowed into the overflow section 76.

Furthermore, the timing of spraying clean water W1 from the water supply nozzle 68 for a predetermined period of time may be different. For example, the valve 67 may be opened for a predetermined period of time before opening the rice distribution valve 79, and clean water W1 may be sprayed into the immersion tank 61 from the water supply nozzle 68 for a predetermined period of time.

(11) Water supply step After the rice distribution step S90 is completed, a water supply step S100 is performed in which a predetermined amount of cooking water W6 is supplied from the water supply unit 100 to the rice cooker 97 to which the soaked rice grains R3 were supplied in the rice distribution step S90.

As shown in Figure 14, the rice cooking water W6, heated to a predetermined temperature by the heater 105, is supplied in a predetermined amount to the rice cooking pot 97, to which the soaked rice grains R3 have been supplied in the rice distribution step S90, through the piping 106 by opening the valve 107.

After the rice distribution step S90 and water supply step S100 are completed, the rice cooker pot 97 containing a predetermined amount of soaked rice grains R3 and a predetermined amount of cooking water W6 is transported by conveyor belt 98 to a lid-covering device (not shown). The lid of the rice cooker pot 97 is then placed over it by the lid-covering device, and the rice cooker pot 97 is transported by conveyor belt 98 to a continuous rice cooking device (not shown).

In this embodiment, the water supply step S100 is performed after the rice distribution step S90, but the rice distribution step S90 may be performed after the water supply step S100 has started. Alternatively, the rice distribution step S90 and the water supply step S100 may be performed simultaneously. This shortens the time required from the start of the rice distribution step S90 to the end of the water supply step S100 for one rice cooker 97, allowing the preparation for cooking the same amount of delicious rice to be completed in a shorter time.

(12) Purification step The air-containing rice water W3 separated in the separation steps S51 and S60 and the immersion water W4 that overflowed in the immersion step S80 are mixed to form air-containing rice water W5 mixed with the immersion water, and the purification step S110 is performed in the purification unit 120.

As shown in Figure 15, the air-containing rice water W3 separated in separation steps S51 and S60 and the immersion water W4 overflowed in immersion step S80 flow down and mix through the second return pipe 77, and the air-containing rice water W5 mixed with the immersion water flows down to the first purification tank 121 of the purification unit 120.

The air-infused rice water W5, which flows down the second return pipe 77, enters the water surface of the rice water W2 stored in the second return pipe 77 up to water level H6, while entraining the air within the second return pipe 77. As a result, some of the rice bran contained in the air-infused rice water W5, which is mixed with the soaking water, turns into rice bran foam.

Then, the rice-supplied water W5, which contains air and is mixed with the immersion water, flows down from the second return pipe 77 to the first purification tank 121, and mixes with the rice-supplied water W2 stored in the first purification tank 121.

The rice bran water W2 stored in the first purification tank 121 contains, as described above, rice bran foam generated when it flows down the second return pipe 77 and hits the surface of the rice bran water W2, entraining air, and rice bran foam that flows together with the immersion water W4 stored in the immersion tank 61 and overflows into the overflow section 76. When the air-containing rice bran water W5, mixed with the immersion water, mixes with the rice bran water W2 stored in the first purification tank 121, the rice bran foam floats on the surface of the rice bran water W2 stored in the first purification tank 121.

Then, air-containing rice bran water W5, which is a mixture of soaking water and the rice water W2 stored in the first purification tank 121, is added. The water level of the rice water W2, which had been stored in the first purification tank 121 up to the full water level H6, rises, and the rice water W2, along with the rice bran foam floating on the surface of the rice water W2, is discharged through the drain pipe 122a by the drain hopper 122.

Furthermore, when the air-containing rice-supplying water W5, mixed with soaking water, is allowed to flow from the second return pipe 77 to the first purification tank 121, the flow of the air-containing rice-supplying water W5 flows in a straight line within the first purification tank 121 and collides with the flow restricting member 127. This prevents the flow of the air-containing rice-supplying water W5 from flowing directly through the third return pipe 125 to the second purification tank 128.

Then, the rice bran foam is retained in the first purification tank 121, and the rice bran foam, along with the supplied rice water W2 exceeding a predetermined water level, is allowed to overflow into the first purification tank 121 and be effectively discharged into the drain hopper 122.

Furthermore, if a large amount of rice bran foam is generated and retained in the first purification tank 121, the rice bran foam will flow into the drain hopper 122, overflowing into it. Therefore, the rice bran foam can be discharged into the drain hopper 122 without overflowing the supplied rice water W2 into the drain hopper 122.

Furthermore, by storing the air-containing rice-transporting water W5, which is a mixture of the immersion water that has flowed down from the second return pipe 77 to the first purification tank 121, in the first purification tank 121, the air component of the air-containing rice-transporting water W5 mixed with the immersion water, and the air component that was drawn in when the air-containing rice-transporting water W5 flowed down the second return pipe 77 and hit the surface of the rice-transporting water W2, rise to the surface of the rice-transporting water W2 as bubbles, and can be released into the atmosphere from the surface of the rice-transporting water W2 stored in the first purification tank 121.

Furthermore, the flow of air-containing rice-supplied water W5, which is a mixture of immersion water that has flowed from the second return pipe 77 to the first purification tank 121, collides with the flow restricting member 127. This causes the air component in the rice-supplied water W2 within the first purification tank 121 to form bubbles that rise to the surface of the water, allowing them to be released into the atmosphere from the water surface of the rice-supplied water W2 stored in the first purification tank 121.

As a result, some of the air components in the rice water W2 supplied from the first purification tank 121 form bubbles, causing the remaining rice bran components in the rice water W2 to float to the surface and be discharged together with the rice water W2 from the wastewater hopper 122.

Furthermore, the air-containing rice water W5, which is a mixture of the immersion water that flows from the second return pipe 77 to the first purification tank 121, contains crushed rice grains R4. These crushed rice grains R4 settle and are stored at the bottom of the first purification tank 121.

The water level H6 in the first purification tank 121 is adjusted by valve 126 so that it is higher than the water level H7 in the second purification tank 128.

Therefore, due to the difference in water level H6 between the first purification tank 121 and the second purification tank 128 (H7), the rice-supplied water W2 stored in the first purification tank 121 flows through the third return pipe 125 to the second purification tank 128.

The rice water W2 that flows into the second purification tank 128 is drawn back into the pump 29, which is continuously operating, via the filter 134 and piping 28, and then discharged back into the pump 29. The rice water W2 discharged from the pump 29 flows again into the ejector 26 and then flows through the rice supply pipe 31 to the separation unit 40.

Furthermore, during the operation of the rice cooking pre-treatment system 10, depending on the timing, only the air-containing rice water W3 separated in separation steps S51 and S60, or only the immersion water W4 overflowed in immersion step S80, may flow down through the second return pipe 77 and flow into the first purification tank 121 of the purification unit 120. Even in this case, the purification step S110 described above can be performed in the same manner.

Furthermore, while the second purification tank 128 can drain the rice-supplied water W2 exceeding the water level H7 through the overflow drain pipe 132, it is preferable to adjust the flow rate of the valve 126 to drain more of the rice-supplied water W2 from the first purification tank 121, which can effectively discharge the rice bran foam into the drain hopper 122, thereby discharging the rice bran foam along with the drained rice-supplied water W2.

(13) End step A predetermined amount of polished rice grains R1 is placed in the rice cooker pot 97 as soaked rice grains R3, and after supplying a predetermined amount of cooking water W6, the end step S120 is performed to prepare for the next preparation step S10.

First, after completing the supply of a predetermined amount of polished rice grains R1, the supply of polished rice grains R1 to the introduction guide 21 shown in Figure 1 is stopped, and the supply step S20 is completed.

Next, after stopping the supply of polished rice grains R1, the pump 29 of the rice washing section 20 is operated for a predetermined time, for example, one minute, and then stopped, and the valve 24 is closed. This ensures that the supplied polished rice grains R1 flow reliably into the separation section 40, and that the rice bran, crushed rice grains R4, etc., adhering to the rice washing section 20 and the separation section 40 are allowed to flow down into the first purification tank 121 of the purification section 120.

Then, the rice distribution valve 79 is opened, and a portion of the soaked rice grains R3 stored in the soaking tank 61, equivalent to the amount needed for the rice cooker 97, is transferred to the separate rice distribution container 92 and supplied to the rice cooker 97. This completes the soaking step S80 and the rice distribution step S90.

After completing the immersion step S80 and the rice distribution step S90, the valve 102 of the water supply unit 100 is closed, and then the power to the control panel 141 is turned off. Then, the valve 131 of the purification unit 120 is closed.

Then, the valve 124 installed in the drain pipe 123 of the first purification tank 121 is opened, and the rice water W2 stored in the first purification tank 121, the crushed rice grains R4 that have settled at the bottom and are stored, and the rice bran foam floating on the surface of the rice water W2 are discharged. At the same time, the overflow water drain pipe 132 of the second purification tank 128 is removed, and the rice water W2 stored in the second purification tank 128 is drained through the drain outlet 128a and the drain pipe 133.

Furthermore, the rice supply water W2 stored in the first purification tank 121 and the second purification tank 128 is discharged, and the rice distribution valve 79 is manually opened. When the rice distribution valve 79 is opened, the soaking water W4 stored in the soaking tank 61 and any remaining soaked rice grains R3 flow through the piping 78 into the separated rice distribution container 92.

The soaking water W4 flows from the second water receiving section 93 to the drain pipe 94 and is drained. The soaked rice grains R3 remaining in the soaking tank 61 and flowing down with the soaking water W4 into the separation and distribution container 92 can be discharged by manually operating the shutter 95 and opening the opening at the bottom of the separation and distribution container 92. These can then be collected using a sieve or similar.

Next, using a hose connected to a water tap (not shown), clean water is sprayed into the rice washing section 20, separation section 40, immersion section 60, rice distribution section 90, and purification section 120 to clean them.

If the receiving cylinder 22 and washing means 32 of the rice washing section 20, the diffuser 42 and separator 43 of the separation section 40, the fixed compartment member 72 and movable compartment member 73 of the immersion section 60, the immersion tank 61, etc., are contaminated with rice bran or the like, they should be cleaned by spraying water on each component.

In this process, the lid 41 of the separation unit 40 can be removed from the rice supply pipe 31 and the first water receiving unit 44. Furthermore, the separator 43, with its fitting portion 43f fitted into the flow pipe 46, can be removed from the first water receiving unit 44. This allows for efficient cleaning of the lid 41, the diffuser 42 integrated with the lid 41, and the separator 43.

In addition, after lifting and removing the fixed compartment member 72 and movable compartment member 73 of the immersion section 60 from the locked frame 71, the frame 71 is removed from the four protrusions on the edge of the immersion tank 61. Then, by pulling the chain 65 upward and lifting the guide plate 64, to which the support member 63 is fixed on its lower surface, out of the immersion tank 61, the fixed compartment member 72 and movable compartment member 73, the support member 63, and the guide plate 64 can also be cleaned.

Furthermore, by removing the drain hopper 122 of the purification unit 120 from the first purification tank 121 and the overflow drain pipe 132 from the second purification tank 128, the drain hopper 122 and the overflow drain pipe 132 can be cleaned.

After cleaning these components, the reverse procedure of removal can be followed to install each component in a clean state.

Then, after cleaning and installing each component is complete, the rice distribution valve 79 of the immersion section 60 and the valve 124 of the drain pipe 123 of the first purification tank 121 are closed, and the overflow water drain pipe 132 of the second purification tank 128 is inserted into the drain port 128a, in preparation for the next preparation step S10.

Thus, in this embodiment of the rice pre-treatment system 10, the entire system can be easily cleaned by operating several valves and the pump 29, removing the components of each part, and then spraying clean water using a hose connected to a water tap.

Furthermore, when cleaning the separator 43 by spraying it with clean water, the separator 43 may be cleaned within the first water receiving section 44. This eliminates the need to remove the separator 43 from the first water receiving section 44 for cleaning, and also prevents damage from dropping the removed separator 43.

Furthermore, depending on the condition of the polished rice grains R1, the first return pipe 45 may be connected directly to the drainage system instead of to the second return pipe 77, depending on the predetermined condition of the polished rice grains R1 supplied to the rice washing section 20. In this case, the immersion water W4 and rice bran foam flowing over the upper end of the wall 76a of the overflow section 76 of the immersion tank 61 will flow down through the second return pipe 77 and into the first purification tank 121.

(Regarding the rice washing cycle)
As described above, the rice pre-processing system 10 of this embodiment performs a supply step S20, a rice washing step S30, a diffusion step S40, a first separation step S51, a induction step S52, a second separation step S60, a fluidization step S70, a soaking step S80, a rice distribution step S90, a water supply step S100, and a purification step S110, allowing for the continuous supply of soaked rice grains R3 and cooking water W6 to the rice cooker 97. By repeating each of these continuously supplying steps, a rice washing cycle can be formed that allows for the supply of a large amount of polished rice grains R1 as soaked rice grains R3 to the rice cooker 97.

It is preferable that the polished rice grains R1 supplied in a single rice washing cycle are supplied to the rice cooker pot 97 as soaked rice grains R3 in the rice distribution step S90 within the same rice washing cycle.

Furthermore, the rice washing section 20 is not limited to using the static mixer described in this embodiment; other rice washing devices can also be employed.

For example, another rice washing device could be a circulating type rice washing device in which the water stored in the rice washing tank is pumped into a fluidized pipe, returned to the rice washing tank, and washed while circulating, and the washed rice is then sent to the separation section 40 via a rice supply pipe 31 along with the water.

Furthermore, a screw-type rice washing device can be used, in which rice and water are washed while flowing along a rotating screw in the rice washing tank, and the washed rice is then sent to the separation unit 40 via a rice supply pipe 31 along with the water. In these cases, the fluid flowing from the rice supply pipe 31 to the separation unit 40 may be a mixture of air-free water and pre-washed rice grains.

As described above, the rice pre-treatment method and system of this embodiment effectively remove the rice bran foam floating on the surface of the soaking water along with the soaking water, thereby reducing the amount of rice bran foam floating on the surface of the soaking tank and allowing the soaking tank to be used cleanly.

Furthermore, the soaking water used to immerse the pre-washed rice grains in the soaking tank can be kept clean. The soaked rice grains, along with clean cooking water, are then supplied to the rice cooker. The rice cooker is then covered and heated, resulting in delicious rice without any bran odor.

In addition, in the separation section, the pre-washed rice grains, which have become less fluid after being separated from the mixed fluid of air-containing rice water and pre-washed rice grains, are smoothly flowed downward by the remaining rice water or the rice water flowing to the draining section via the induction step, thereby reducing the amount of pre-washed rice grains remaining inside the separator wall as much as possible. By reducing the amount of pre-washed rice grains remaining inside the separator wall as much as possible, the amount of pre-washed rice grains processed per unit time by the separator can be increased.

In this embodiment, the rice grains supplied to the introduction guide 21 of the rice washing unit 20 shown in Figure 2 are polished rice grains R1. However, pre-washed rice grains may also be supplied to the introduction guide 21. In that case, since pre-washed rice does not need to be washed, it is preferable that the rice washing unit 20 of the pre-cooking processing system 10 does not include a rice washing means 32.

Furthermore, this invention is not limited to polished rice grains; it can also be applied to the pretreatment of unpolished rice, such as brown rice, and other grains.

Furthermore, the present invention is not limited to the configurations and shapes exemplified above, and various modifications are possible. Naturally, it is also possible to modify the configuration, such as by omitting parts, without departing from the spirit of the present invention.

W1 Clean water W2 Water used to deliver rice W3 Water used to deliver rice containing air W4 Soaking water W5 Water used to deliver rice containing air mixed with soaking water W6 Cooking water M1 Mixed fluid of water used to deliver rice containing air and polished rice grains M2 Mixed fluid of water used to deliver rice containing air and pre-washed rice grains M3 Soaking water and soaked rice grains R1 Polished rice grains (rice grains)
R2 Washed rice grains (rice grains)
R3 Soaked rice grains (rice grains)
R4 Crushed rice grains (rice grains)

10 Rice Pre-processing System 20 Rice Washing Section 21 Introduction Guide 22 Receiving Tube 23 Piping 24 Valve 25 Clean Water Nozzle 26 Ejector 27 Suction Port 28 Piping 29 Pump 30 Valve 31 Rice Supply Pipe (Piping)
31a Opening 32 Rice washing means 40 Separation section 41 Lid 41a Guiding section 42 Diffuser 42a Inclined section 42b Horizontal section 43 Separator 43a Wall surface 43b Upper flow section (flow section)
43c Drainage section 43d Downward flow section (flow section)
43e Hole 43f Fitting part 43g Top surface part 44 First water receiving part 45 First return piping (piping)
45a Opening 46 Flow pipe 46a Opening 60 Immersion section 61 Immersion tank 61a Flow opening 62 Lid 62a Handle 63 Support member 64 Guide plate 65 Chain 66 Water supply pipe (piping)
67 Valve 68 Water supply nozzle 69 Water level detection means 70 Storage volume detection means 71 Frame 72 Fixed partition member (partition member)
72a Bent portion 72b Folded portion 72c Notched portion 72d Opening 73 Movable partition member (partition member)
74 Hinge 75 Compartment 76 Overflow section 76a Wall section 77 Second return piping (piping)
77a Opening 78 Piping 79 Rice distribution valve (valve)
80 Ridge 80a Ridge 80b Ridge 90 Rice distribution section 91 Rice distribution amount adjuster 92 Separation rice distribution container 92a Hole 93 Second water receiving section 94 Drain pipe (piping)
95 Shutter 96 Driving mechanism 97 Rice cooker pot 98 Conveyor 100 Water supply section 101 Water supply pipe (piping)
102 Valve 103 Float valve 104 Tank 105 Heater 106 Piping 107 Valve 120 Purification section 121 First purification tank 122 Drain hopper 122a Drain pipe (piping)
123 Drain pipe (piping)
124 Valve 125 Third return piping (piping)
126 Valve 127 Flow regulating member 128 Second purification tank 128a Drain outlet 129 Float valve 130 Water supply pipe 131 Valve 132 Overflow water drain pipe 133 Drain pipe 134 Filter 140 Control unit 141 Control panel

S10 Preparation step S20 Supply step S30 Rice washing step S40 Diffusion step S51 First separation step (separation step)
S52 Induction step S60 Second separation step (separation step)
S70 Fluidization step S80 Immersion step S90 Rice distribution step S100 Water supply step S110 Purification step S120 End step

Claims (10)

Polished rice grains are washed to become pre-washed rice grains.
The process includes a soaking step in which the pre-washed rice grains are dropped and flowed into a soaking tank containing soaking water, and the pre-washed rice grains are soaked in the soaking water to become soaked rice grains.
In the aforementioned immersion step,
The opening of the flow pipe, which extends in a substantially vertical direction, is positioned below the water level of the immersion water to form the water level of the immersion water within the flow pipe.
A method for pre-treating rice before cooking, characterized by causing the pre-washed rice grains, which have been allowed to fall and flow through the flow pipe, to land on the surface of the soaking water formed inside the flow pipe. In the immersion step,
The rice pretreatment method according to claim 1, characterized in that, within a partitioned area which is a region where the surface of the immersion water is partitioned by the inside of the wall of the immersion tank and a plate-shaped partitioning member, pre-washed rice grains that have been allowed to fall and flow through a flow pipe are brought to the surface of the immersion water formed inside the flow pipe. Polished rice grains are washed to become pre-washed rice grains.
The process includes a soaking step in which the pre-washed rice grains are dropped and flowed into a soaking tank containing soaking water, and the pre-washed rice grains are soaked in the soaking water to become soaked rice grains.
In the aforementioned immersion step,
A method for pre-treating rice before cooking, characterized in that the pre-washed rice grains, which have been allowed to fall and flow, are brought to the surface of the soaking water within a partitioned area, which is a region defined by the inside of the wall surface of the soaking tank and a plate-shaped partitioning member. In the immersion step,
The opening of the flow pipe, which extends in a substantially vertical direction, is positioned below the water level of the immersion water to form the water level of the immersion water within the flow pipe.
The method for pre-treating rice for cooking according to claim 3, characterized in that, within a partitioned area, pre-washed rice grains that have been allowed to fall and flow through the fluidized pipe are brought to the surface of the immersion water formed inside the fluidized pipe. By repeatedly changing the direction of flow of pre-washed rice grains that have been washed from polished rice grains, the kinetic energy of the pre-washed rice grains as they flow is reduced.
The method for pre-treating rice for cooking according to any one of claims 1 to 4, characterized in that the washed rice grains, whose kinetic energy has been reduced, are placed in soaking water. A soaking tank that stores a predetermined amount of soaking water and soaks pre-washed rice grains, which are polished rice grains that have been washed, in the soaking water to make soaked rice grains,
A flow pipe extending in a substantially vertical direction, which causes the washed rice grains to fall and flow into the soaking water,
Equipped with,
The opening of the flow pipe is positioned below the water level of the immersion water to form the water level of the immersion water inside the flow pipe.
A pre-treatment system for rice cooking, characterized by causing the pre-washed rice grains, which have been allowed to fall and flow through the fluidized pipe, to land on the surface of the soaking water formed inside the fluidized pipe. It further includes a plate-shaped partitioning member that divides the rice bran foam floating on the surface of the soaking water,
A partitioned area is formed on the surface of the immersion water, which is a region partitioned by the inside of the wall of the immersion tank and the partitioning member.
The rice pre-treatment system according to claim 6, characterized in that, within the aforementioned compartment, pre-washed rice grains that have been allowed to fall and flow through the fluidized pipe are brought to the surface of the immersion water formed inside the fluidized pipe. A soaking tank stores a predetermined amount of soaking water, and soaks pre-washed rice grains, which are polished rice grains that have been washed, in the soaking water to make soaked rice grains,
A plate-shaped partitioning member that partitions the rice bran foam floating on the surface of the immersion water,
Equipped with,
A partitioned area is formed on the surface of the immersion water, which is a region partitioned by the inside of the wall surface of the immersion tank and the partitioning member.
A pre-treatment system for rice cooking, characterized by dropping and flowing the pre-washed rice grains onto the surface of the soaking water within the designated area. It further includes a flow pipe that extends in a nearly vertical direction and causes the washed rice grains to fall and flow into the soaking water,
The opening of the flow pipe is positioned below the water level of the immersion water to form the water level of the immersion water inside the flow pipe.
The rice pre-treatment system according to claim 8, characterized in that the pre-washed rice grains, which have been allowed to fall and flow through the fluidized pipe within a partitioned area, are brought to the surface of the immersion water formed inside the fluidized pipe. The rice pre-treatment system according to any one of claims 7 to 9, characterized in that when the mass of the soaked rice grains located on the ridges of the soaked rice grains stored in the soaking tank is applied to the partition member, at least a part of the partition member rotates toward the outside of the soaking tank.