JP6879033B2 - Grinding roll for rice milling - Google Patents

Description

The present invention relates to a rice milling grinding roll used for polishing sake brewed rice.

Conventionally, a circulation type hard-grinding rice mill is often used for polishing sake brewed rice that is subjected to extreme grinding rice polishing (yield 45% or the like) (Patent Document 1). In this type of rice milling machine for sake brewing, vertically arranged rice milling rolls are arranged in a polishing cylinder, and a polishing chamber is formed between the outer peripheral surface of the rice polishing grinding roll and the inner peripheral surface of the polishing cylinder. After being formed, rice grains are repeatedly supplied to the polishing chamber to perform polishing by grinding.

Grinding rolls for rice milling are usually formed by molding Kongo sand (silicon carbide) together with a binder and sintering it into a cylindrical body (called a Kongo sand roll). Since the sintered body is brittle without a certain wall thickness, the Kongo sand roll has a thick cross section and a large weight (50 to 70 kg) as shown in Patent Document 1.
It should be noted that the Kongo sand roll as a whitening roll has a well-established form of integral molding in which an annular convex portion is provided in several steps in the vertical direction on the surface side of the tubular wall constituting the cylindrical body.

In the rice milling machine for sake brewing of Patent Document 2, it is proposed to reduce the weight of the whitening roll by forming the side surface portion of the whitening roll with a thin metal cylinder. This polishing roll keeps the outer shape of a conventional Kongo sand roll having an annular convex portion, and forms a cylindrical body with a thin metal (metal thin plate) having a uniform thickness of 3 to 15 mm.
The rice milling machine for sake brewing in Patent Document 2 employs diamond abrasive grains in order to improve the grinding efficiency, and is fixed to the surface of the thin-walled cylindrical body. By adopting diamond abrasive grains, the grinding efficiency is improved, and even if the polishing roll is miniaturized, the required grinding efficiency can be secured, and the weight of the polishing roll can be further reduced.

Japanese Unexamined Patent Publication No. 4-11958 Japanese Patent No. 5897301

The current emery sand roll has been completed as a grinding roll for rice milling in terms of both morphology and material, but as described above, it is heavy and difficult to handle during maintenance or replacement of the grinding roll for rice milling.
In addition, when used for a long time, the frictional heat during rice milling is stored in the thick grinding roll for rice milling, which is one of the reasons for raising the rice grain temperature. An increase in the temperature of the rice grains leads to a decrease in the water content of the rice grains, which adversely affects the progress of rice milling such as split rice.
On the other hand, if a cylindrical body is formed of a thin metal body as a core metal like the whitening roll of Patent Document 2 and diamond is used as the abrasive grains, the whitening work can be performed without lowering the grinding efficiency with the lightweight whitening roll. Conceivable.

However, the whitening roll made of thin metal (thin metal plate) with a thickness of 3 to 15 mm is not sturdy, and during long-term whitening work, it may be deformed by the pressure from the rice grains sandwiched between the whitening cylinder and the rice grains. There is a high possibility that it will be deformed as the temperature of the rice rises. It is considered that there is a high possibility of deformation in flat rice milling in which the rice milling pressure is increased.
An object of the present invention is to provide a grinding roll for rice milling, which is lightweight, has high rigidity, and can suppress an increase in rice grain temperature.

[Means 1]
The grinding roll for rice milling of a rigid grinding type rice mill shall consist of a cylindrical body and abrasive grains fixed to the surface thereof.
The cylindrical wall constituting the cylindrical body shall be formed into a double cylindrical hollow structure having an outer wall and an inner wall and a hollow space between them.
[Means 2]
In means 1, the tubular wall constituting the cylindrical body is formed by the outer wall and the inner wall of the thin-walled plate body.
[Means 3]
In means 1, the cylindrical wall constituting the cylindrical body is made of metal.
[Means 4]
In means 1, it is assumed that the cylinder wall constituting the cylindrical body is composed of one or more kinds selected from FRP, synthetic resin, and carbon fiber.
[Means 5]
In means 1, the hollow portion of the cylinder wall is filled with an inert gas such as argon gas or nitrogen gas.
[Means 6]
In means 1, the hollow portion of the cylinder wall is evacuated.
[Means 7]
In means 1, a reinforcing member for maintaining a distance between the outer wall and the inner wall is arranged in the hollow portion of the tubular wall.
[Means 8]
In means 1, the hollow portion of the cylinder wall is filled with foamed resin.
[Means 9]
In the means 1 to 8, the airflow generating means is provided on the inner wall of the cylinder wall on the inner space side surface of the cylindrical body.
[Means 10]
In means 1 to 9, the abrasive grains fixed to the surface of the cylindrical body are cBN abrasive grains fixed by electrodeposition.

By making the cylinder wall hollow, the thickness dimension of the cylinder wall becomes large, but since the thin-walled plate is formed into a hollow structure, the weight of the entire grinding roll for rice milling is reduced.
Since the cylinder wall is provided with a hollow portion to increase the wall thickness of the cylinder wall, the cylinder wall has a large bending moment. Therefore, a highly rigid grinding roll for rice milling can be obtained. In this case, the material of the cylinder wall is not limited to metal, and a synthetic resin or the like having high rigidity can be adopted.
Since the cylinder wall has a hollow portion, the heat capacity as a whole is small, and even if it is used continuously for a long time as a rice milling machine for sake brewing, the grinding roll for rice milling has less heat storage and a large heat dissipation effect. Therefore, the influence of the temperature rise on the rice grains during milling can be suppressed.
If the airflow generating means is provided on the inner wall of the cylinder wall on the inner space side surface of the cylindrical body, the cooling effect on the grinding roll for rice milling is improved.

When the cylinder wall is made of metal, diamond abrasive grains, cBN abrasive grains, SiC abrasive grains and the like can be firmly fixed to the cylinder wall by electrodeposition.

An overall perspective view of a rice milling machine for sake brewing according to an embodiment of the present invention. Right side view (partial cross section) of the rice mill for sake brewing in FIG. An enlarged cross-sectional view of the polished part. Top view of the vertical cross section of the grinding roll for rice milling. A perspective view of a grinding roll for rice milling. [A] is a vertical sectional front view of the tubular wall in the second embodiment, and [B] is a side view (part) along line B in the above [A]. The vertical sectional front view (part) of the cylinder wall in 3rd Example.

The rice milling machine for sake brewing 1 (FIG. 1) of the first embodiment is a circulation type vertical rice milling machine, and includes a whitening unit 2, a storage tank 3, a mangoku unit 4, a grain raising unit 5, and a control unit 6. ..
The polishing portion 2 is a portion for polishing rice grains by a grinding action.
The storage tank 3 supplies rice grains to the whitening portion 2 and temporarily stores the rice grains during the whitening work for the whitening circulation work.

The Mangoku portion 4 is a portion that separates the rice grains and the bran while moving the rice grains refined in the polishing portion 2 downward, and the separated rice grains move to the lower part of the fried grain portion 5.
The fried grain portion 5 lifts the rice grains from the mangoku portion 4 to the top of the storage tank 3 and supplies the rice grains to the storage tank 3 to circulate the rice grains.
The control unit 6 manages these series of operations by a program and a sequence in which parameters can be set.

The whitening section 2, the storage tank 3, and the Mangoku section 4 are installed on the whitening section machine base 7. Further, the fried grain section 5 is installed on the fried grain section machine stand 8.
The fried grain machine base 8 is provided with an upper working table 9, and the polishing part machine table 7 is provided with a lower working table 10.

Under the work management by the control unit 6, the brown rice placed in the storage tank 3 undergoes a whitening action in the whitening part 2 and reaches the Mangoku part 4. The rice grains separated from the bran in the winnowing part 4 are transferred to the lower part of the fried grain part 5, and then the rice grains are fried by the fried grain part 5 to the inlet of the storage tank 3. The rice grains repeat the above-mentioned circulation cycle, and the brown rice initially introduced is finished into the target yield of sake rice.

The polishing portion 2 (FIG. 3) includes a grinding assembly 11, a polishing cylinder 12, and a discharge gutter 13.
The upper part of the whitening cylinder 12 is a rice grain receiving port 14, and the base portion is fixed to the whitening part machine base 7. A part of the base is cut out to form a feeding port 15.
The grinding assembly 11 includes a vertical shaft 16, a holding member 17, a grinding roll 18 for rice milling, and a roll cradle 19, and is assembled around the vertical shaft 16. The rice milling roll 18, the pressing member 17, and the roll cradle 19 are all circular in a plan view, and have a boss with respect to the vertical shaft 16 in the center.
The vertical shaft 16 is pivotally supported in the vertical direction with respect to the milling machine base 7, is maintained in the thrust direction by two bearing mechanisms 20, and is rotatably supported in the radial direction.

A roll cradle 19 is fitted into the vertical shaft 16 and fixed to the vertical shaft 16 at the position of the boss 21, and a grinding roll 18 for rice milling is loosely fitted onto the vertical shaft 16 at the position of the boss 22. At the same time, it is placed on the roll cradle 19, and the pressing member 17 is fitted and inserted into the vertical shaft 16 at the position of the boss 23 above the grinding roll 18 for rice milling. The lower edge of the pressing member 17 comes into contact with the upper surface of the rice milling rolling roll 18, and the pressing member 17 is fixed to the upper end of the vertical shaft 16 by a fastening bolt 24 inserted from above the boss 23.
As a result, the grinding assembly 11 is attached to the milling machine base 7, and the rice milling roll 18 is sandwiched and fixed between the roll pedestal 19 and the pressing member 17 by the fastening bolt 24. Therefore, the grinding assembly 11 is rotated together with the vertical shaft 16.

A polishing chamber 25 is formed between the inner peripheral surface of the polishing cylinder 12 and the outer peripheral surface of the rice polishing roll 18, and the bottom thereof is closed by the outer peripheral portion 26 of the roll cradle 19.
A passive pulley 27 is fixed to the lower end of the vertical shaft 16 and is connected to the drive pulley of the motor M shown briefly by a V-belt.
The feeding port 15 provided at the base of the polishing cylinder 12 is open to the discharge gutter 13, and rice grains are guided to the Mangoku portion 4 through the discharge gutter 13. A pressure adjusting valve 28 is arranged at the feeding port 15. The pressure adjusting valve 28 has an opening degree that changes according to the rice grain pressure in the polishing chamber 25.

The rice-polishing grinding roll 18 (FIGS. 4 and 5) includes a cylindrical body 29 and abrasive grains 30 fixed to the surface thereof.
The tubular wall 31 constituting the cylindrical body 29 is made of an aluminum alloy in this embodiment, has an outer wall 32 and an inner wall 33 of a thin-walled plate having a thickness of 3 to 15 mm, and these are welded at the edge to seal between them. It is formed into a double-cylindrical hollow structure having a hollow portion 34 formed therein.
The outer wall 32 is formed into an annular concavo-convex structure similar to that of a conventional Kongo sand roll by spinning.

Further, the inner wall 33 is basically formed into a tubular shape, a step portion 35 into which the edge portion of the pressing member 17 is fitted is formed on the inner surface of the upper portion, and a step portion 37 for fixing the mounting flange 36 is formed on the inner surface of the lower portion. It is molded. The pressing member 17 (FIG. 3) has a conical upper surface and is smoothly continuous with the surface of the cylindrical body 29. Abrasive grains 30 may also be arranged on the surface of the roll pressing member 17.
A boss 22 is provided at the center of the mounting flange 36. The boss 22 is for attaching the rice-polishing grinding roll 18 to the vertical shaft 16.
The formed hollow portion 34 is evacuated. Alternatively, after creating a vacuum, an inert gas such as argon gas or nitrogen gas is filled.

The thickness dimension of the cylinder wall 31 constituting the cylindrical body 29 is 20 mm or more and 60 mm or less, preferably 25 mm or more and 40 mm or less in consideration of the rigidity of the rice polishing rolling roll 18. This is the thickness dimension of the cylinder wall 34, which is the wall thickness of the cylindrical body 29 formed by the outer wall 32 and the inner wall 33 forming the hollow portion 34.
That is, the rice milling roll 18 is provided with the hollow portion 34 to increase the thickness of the cylinder wall 34 to maintain sufficient rigidity for the whitening work, and the outer wall 32 and the inner wall 33 are formed of a thin plate body. The weight of the entire grinding roll 18 for rice milling has been reduced.
The abrasive grains 30 fixed to the surface of the cylindrical body 29 are cBN abrasive grains fixed (electroplated) by nickel plating (plating) or the like with the cylindrical body 29 made of an aluminum alloy as a core metal.

When the motor M is driven, the vertical shaft 16 is driven via the passive pulley 27, and the rice milling rolling roll 18 rotates in the milling cylinder 12.
Rice grains are sent from the storage tank 3 to the whitening chamber 25 through the receiving port 14 into the whitening portion 2, and the rice grains are ground (polished) between the whitening cylinder 12 and the rice polishing rolling roll 18. The rice grains that have passed through the polishing chamber 25 are received by the outer peripheral portion 26 of the roll cradle 19, and are eventually sent out from the feeding port 15 to the discharge gutter 13.

At this time, the grinding roll 18 for rice milling is lightweight and can reduce the power as compared with the conventional emery sand roll, while the cylinder wall 31 of the cylindrical body 29 has a sufficient thickness dimension and high rigidity, so that it is polished. It can withstand the pressure sometimes received from rice grains and can perform precise whitening work.
Further, since the hollow portion 34 of the cylinder wall 31 of the rice polishing roll 18 has a heat insulating effect and the outer wall 32 and the inner wall 33 constituting the cylinder wall 31 are thin plates, the heat capacity is small, so that the rice polishing grinding roll The heat storage of 18 is suppressed, and the temperature rise of the rice grains due to the polishing work can be suppressed.

FIG. 6 is a portion of the tubular wall 31 in the second embodiment, which has a structure in which a hollow portion 34 is formed by an outer wall 32 and an inner wall 33, and a honeycomb structure 38 made of an aluminum alloy is loaded in the hollow portion. There is. The honeycomb structure 38 can reduce the heat capacity of the cylinder wall 31 as much as possible to avoid heat storage, and serve as a reinforcing member for maintaining the distance between the outer wall 32 and the inner wall 33, so that the rigidity of the cylinder wall 31 can be increased.
FIG. 7 is a portion of the tubular wall 31 in the third embodiment, which has a structure in which a hollow portion 34 is formed by an outer wall 32 and an inner wall 33, and the hollow portion is filled with a foamed resin 39. The foamed resin 39 also serves as a reinforcing member for maintaining the distance between the outer wall 32 and the inner wall 33 while avoiding heat storage by reducing the heat capacity of the cylinder wall 31 as much as possible, and can enhance the rigidity of the cylinder wall 31.

The examples have been described above.
As the material constituting the outer wall 32 and the inner wall 33 of the tubular wall 31, FRP, resin, ABS, carbon fiber and the like can be considered in addition to metal.
Means other than electrodeposition may be used, such as using an adhesive to fix the abrasive grains to the surface of the cylindrical body 32.
In the embodiment, the surface form of the rice milling grinding roll 18 is the same as that of the conventional emery sand roll, but the form in which the number of annular protrusions is increased or eliminated is a design matter.
Further, although not shown, it is also possible to provide air disturbance or ventilation means such as a blade plate on the outer surface of the outer wall 32 or the inner surface of the inner wall 33 to improve the cooling of the rice milling grinding roll 18.

The present invention is not limited to the above-described embodiment, and its configuration can be appropriately changed as long as it does not deviate from the scope of the invention.

It can be used for vertical shaft rotary rice milling machines, mainly rice milling machines for sake brewing.

1 Rice milling machine for sake brewing 2 Polishing part 3 Storage tank 40,000 stones part 5 Fried grain county 6 Control unit 7 Polishing part machine stand 8 Grain-raising part machine stand 9 Upper workbench 10 Lower workbench

11 Grinding assembly 12 Polishing cylinder 13 Discharge gutter 14 Receiving port 15 Feeding port 16 Vertical shaft 17 Holding member 18 Grinding roll for rice milling 19 Roll cradle 20 Bearing mechanism

21 Boss (of roll cradle)
22 Boss (for grinding rolls for rice milling)
23 Boss (of holding member)
24 fastening bolt
25 Polishing chamber 26 Outer peripheral part 27 Passive pulley 28 Pressure regulating valve 29 Cylindrical body 30 Abrasive grains

31 Cylinder wall 32 Outer wall 33 Inner wall 34 Hollow part 35 Steps 36 Mounting flange 37 Steps 38 Honeycomb structure 39 Foamed resin

Claims (10)

It is a grinding roll for rice milling of a rigid grinding type rice milling machine.
It consists of a cylinder and abrasive grains fixed to its surface.
A grinding roll for rice milling, wherein the cylindrical wall constituting the cylindrical body is formed into a double cylindrical hollow structure having an outer wall and an inner wall and a hollow space between them. The grinding roll for rice milling according to claim 1, wherein the tubular wall constituting the cylindrical body is formed by an outer wall and an inner wall of a thin-walled plate body. The grinding roll for rice milling according to claim 1, wherein the tubular wall constituting the cylindrical body is made of metal. The grinding roll for rice milling according to claim 1, wherein the tubular wall constituting the cylindrical body is made of one or more kinds selected from FRP, synthetic resin, and carbon fiber. The grinding roll for rice milling according to claim 1, wherein the hollow portion of the cylinder wall is filled with an inert gas. The grinding roll for rice milling according to claim 1, wherein the hollow portion of the cylinder wall is evacuated. The grinding roll for rice milling according to claim 1, wherein a reinforcing member for maintaining a distance between the outer wall and the inner wall is arranged in the hollow portion of the tubular wall. The grinding roll for rice milling according to claim 1, wherein the hollow portion of the cylinder wall is filled with a foamed resin. The grinding roll for rice milling according to any one of claims 1 to 8, wherein the airflow generating means is provided on the inner space side of the cylindrical body, which is the inner wall of the tubular wall. The grinding roll for rice milling according to any one of claims 1 to 9, wherein the abrasive grains fixed to the surface of the cylindrical body are cBN abrasive grains fixed by electrodeposition.

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