JP3335125B2 - Milling machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinder for finely grinding grains such as tea with a mortar.

[0002]

2. Description of the Related Art As a conventional milling machine, a substantially disk-shaped upper mill and a lower mill are brought into close contact with each other, and grooves are formed on opposing surfaces of the upper mill and the lower mill, respectively. What rotated one side is known. When grains, such as tea leaves, are supplied between the upper mill and the lower mill from the supply port formed in the upper mill, the grains enter the grooves formed in the upper mill and the lower mill. The grain is sandwiched between the edge of the groove of the upper mill and the edge of the groove of the lower mill, and is crushed by a shear force. In addition, the pulverized material is centrifuged by intersecting the grooves of the upper mill and the grooves of the lower mill at an acute angle during rotation. For this reason, the pulverized material is discharged from the outer periphery of the facing surface.

[0003] As another example of a milling machine, there is known a grinder in which a mortar-shaped lower mill and a mortar-shaped upper mill are opposed to each other and a groove is formed in the opposed surface (Japanese Patent Laid-Open No. 10-43615).
Reference). By forming the upper mill and the lower mill into a mortar shape, a gravitational force opposing the centrifugal force is generated in the pulverized material.
For this reason, the pulverized material moves back and forth between the upper mill and the lower mill and stays for a long time. By increasing the residence time of the pulverized material, the particle size of the pulverized material can be reduced. In general,
Because tea leaves are required to be finely crushed,
The grinder provided with the mortar-shaped lower mill and upper mill is suitable for pulverizing tea leaves.

[0004]

However, in a conventional milling machine in which grooves are formed on opposing surfaces of a generally disk-shaped upper mill and lower mill, it is difficult to reduce the particle size of the pulverized material. Not suitable for crushing tea leaves. In addition, in the case of using a mortar-shaped lower mill and upper mill, the particle size of the pulverized material can be made fine, but the residence time between the upper mill and the lower mill becomes longer, and Cannot grind grains and the like.

[0005] Therefore, an object of the present invention is to provide a powder grinder that can grind grains and the like in a short time and can reduce the particle size of the grind.

[0006]

Hereinafter, the present invention will be described. In addition, in order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are added in parentheses, but the present invention is not limited to the illustrated embodiment.

According to the first aspect of the present invention, the upper mill (5) and the lower mill (6) are opposed to each other, and the upper mill (5) and the lower mill (6) are provided.
And a grinder that grinds grains and the like by relatively rotating the upper and lower mills (5) and (6). , 6a )
When, with the planar portion (5a, 6a) taper portion formed on the periphery of the (5b, 6b), wherein the mortar (5) and the lower die (6) of each of said flat portion (5a, 6a) and Of the tapered portions ( 5b , 6b), the flat portions (5a, 6a )
A groove is formed only in the upper mill (5) and the lower mill (6).
Is the center of the plane portion (5a, 6a)
The upper mill so that it gradually narrows
(5) or the flat surface of at least one of the lower mill (6).
The surface parts (5a, 6a) are dented and the table of the upper mill (5) is dented.
The taper part (6b) of the pa part (5b) and the lower mill (6)
The above-mentioned problem is solved by a grinding machine characterized by being brought into close contact .

According to the present invention, when the upper mill (5) and the lower mill (6) are relatively rotated, the cereals and the like become flat with the flat portions (5a, 5a) of the upper mill (5) and the lower mill (6). Due to the grooves formed in 6a), they are subjected to shearing force and are roughly crushed.
Then, the pulverized material is centrifuged. Flat part (5a, 6a)
The tapered portions (5b, 6b) are formed on the periphery of the tapered portion, so that the tapered portion (5b) and the tapered portion (6b) come into close contact with each other and rub. For this reason, it is centrifuged between the tapered portion (5b) and the tapered portion (6b) to form a flat portion (5a, 6b).
The crushed material moved from a) to the tapered portions (5b, 6b) is
It can be finely pulverized. In addition, the plane portion (5a,
6a) is formed substantially flat, so that the pulverized material is flat (5a).
The residence time during a, 6a) is short. For this reason, the total crushing time can be shortened as compared with the case where a conventional mortar-shaped mortar is used. According to the present invention, at least one flat portion (5) of the upper mill (5) or the lower mill (6) is provided.
a, 6a), so that the tapered portion (5b, 6b)
Can be surely adhered to each other. Further, a gap generated between the upper mill (5) and the lower mill (6) is formed by a flat portion (5a, 6).
Since the size of the pulverized material gradually decreases from the center of the flat portion (5a, 6a) toward the periphery, the particle size gradually decreases from the center to the outer periphery of the flat portion (5a, 6a) and moves to the tapered portion (5b, 6b). . Therefore, the tapered portion (5b) and the tapered portion (6
It becomes easy to pulverize the pulverized material between b) and b). Further, a gap is formed between the flat portion (5a) and the flat portion (6a), so that the groove formed on the upper mill (5) and the groove formed on the lower mill (6) form a galling. There is no danger.

[0009]

[0010]

According to a second aspect of the present invention, in the first aspect of the present invention, an upper mill (5) or a lower mill (5) is provided inside each of the tapered portions (5b, 6b) of the upper mill (5) and the lower mill (6). A horizontal portion orthogonal to the rotation center (A) of the mortar (6) is provided, and the flat portions (5a, 6a) are formed inside the horizontal portion.

According to the present invention, the horizontal portion (5c) of the upper mill (5) and the horizontal portion (6c) of the lower mill (6) are brought into close contact with each other, and between the horizontal portions (5c, 6c), Flat part (5
a, 6a) can be finely pulverized by centrifugation from
The pulverized material can be pulverized more reliably.

According to a third aspect of the present invention, in the first or second aspect , the tapered portion (5b, 6b) is inclined upward toward the outer periphery of the tapered portion (5b, 6b). And

According to the present invention, the tapered portions (5b, 6)
In the case of b), the pulverized material stays between the tapered portions (5b, 6b) for a long time because it is inclined upward toward the outer periphery. Therefore, the pulverized material can be finely pulverized more reliably, and the particle size of the pulverized material can be kept constant.

[0015] The invention of claim 4 is the invention according to any one of claims 1 to 3, that is adhered the upper die (5) and the lower die (6) by the elastic force of the elastic body (25) Features.

According to the present invention, a constant pressure can be applied to the tapered portions (5b, 6b) of the upper mill (5) and the lower mill (6), and the pulverized material having a small variation and a constant particle size. Can be obtained.

[0017]

1 to 8 show a grinding machine according to an embodiment of the present invention. This mill is mainly used for grinding tea leaves at home and is used on a table. As shown in FIG. 1, the external appearance of the milling machine has a substantially cylindrical shape. On the top of the grinder, there is an inlet 1 for tea leaves.
A cup 2 for taking out crushed powdered tea leaves is detachably mounted on the upper side surface. A timer 3 is provided below the cup 2. The crushing time of the tea leaves is adjusted by the timer 3.

FIG. 2 shows a cross section of the milling machine. The grinding machine includes a case 4, an input port 1 provided on an upper surface of the case 4, an upper rotor 5 incorporated inside the case 4, and a lower rotor 6 rotatably arranged on a lower surface of the upper rotor 5. A drive mechanism 7 for rotating the lower rotor 6, a tray 9 for receiving powdered tea discharged from between the upper rotor 5 and the lower rotor 6, and a cup 2 for collecting the powdered tea stored in the tray 9 are provided. The upper rotor 5 functions as an upper mill, and the lower rotor 6 functions as a lower mill.

The charging port 1 is opened on the upper surface of the case 4. This inlet 1 is closed with a plastic cap 10. The end of the cap 10 is grasped, and the cap 10 is rotated with the hinge 10a as a fulcrum to feed the tea leaves.
A tea leaf guide surface 11 is vertically provided around the inlet 1 toward the upper rotor 5 incorporated below.

The upper rotor 5 is attached to the case 4 via an upper rotor support plate 12. On the upper surface of the upper rotor 5,
A concave portion 24 is formed and fits with a protrusion 12 a formed on the lower surface of the upper rotor support plate 12. The upper rotor support plate 12
It has several engagement claws 12b on the outer periphery and engages with the case 4. The upper rotor 5 is provided with an upper rotor support plate 1 disposed on the upper surface of the upper rotor 5 by a spring force from below the leaf spring 25.
It is biased to 2.

FIG. 3 and FIG. 4 show the upper rotor 5. As shown in FIG. 3, the upper rotor 5 has a substantially disk shape. A tapered portion 5b is formed on the periphery of the lower surface of the upper rotor 5 (that is, the surface facing the lower rotor 6). The tapered portion 5b is inclined upward toward the outer periphery. The inclination angle α of the tapered portion 5b with respect to the horizontal plane is set to 30 degrees.
Further, the tapered portion 5b is formed smoothly. Tapered part 5
A flat portion 5a is formed flat inside b. As shown in FIG. 4, a main groove 20 extending radially from the center so as to divide the whole into eight is formed in the plane portion 5a. Main groove 20
Between them, a plurality of sub-grooves 21 are formed parallel to the main groove 20 located in the counterclockwise direction. The main groove 20 and the sub groove 21
Is formed in a semicircular cross section as shown in FIG. In the center of the upper rotor 5, a core receiving hole 22 into which the mandrel 13 is inserted.
Is penetrated. A tea leaf supply port 23 penetrates slightly outside the center of the upper rotor 5. A depression is formed near the upper surface of the supply port 23. In the hollow, the tea leaves are stored so as to be continuously sent to the supply port 23. As the material of the upper rotor 5, a ceramic material containing alumina as a main component is used.

FIG. 6 and FIG. 7 show the lower rotor 6. The lower rotor 6 also has a substantially disk shape. A tapered portion 6b is also formed on the periphery of the upper surface of the lower rotor 6 (that is, the surface facing the upper rotor 5). The tapered portion 6b is also inclined upward toward the outer periphery. The inclination angle β of the tapered portion 6b with respect to the horizontal plane is also set to 30 degrees. The outer diameter of the tapered portion 6b is
It is equal to the outer diameter of the tapered portion 5b. Therefore, when the upper rotor 5 and the lower rotor 6 are overlapped, the tapered portion 5b and the tapered portion 6b come into close contact with each other. Also, the upper surface of the tapered portion 6b is formed to be smooth, similarly to the tapered portion 5b. A substantially flat plane portion 6a is formed inside the tapered portion 6b. This flat portion 6a is recessed. That is, the height of the center point B of the plane portion 6a is set slightly lower than the height of the outer peripheral point A. A main groove 30 extending radially from the center so as to divide the whole into eight is formed in the flat part 5a. The main groove 30 located in the counterclockwise direction is located between the main grooves 30.
A plurality of sub-grooves 31 are formed in parallel with. The main groove 30 and the sub groove 31 are also formed in a semicircular cross section. A mandrel through hole 32 into which a mandrel is inserted is formed at the center of the lower rotor 6. On the lower surface of the lower rotor 6, a lower rotor recess 3 fitted with a shaft flange plate 13a formed integrally with the shaft 13 is provided.
3 is formed. By fitting the lower rotor 6 to the mandrel 13, the lower rotor 6 rotates together with the mandrel 13.
The lower rotor 6 is also made of a ceramic material containing alumina as a main component.

As shown in FIG. 1, the drive mechanism 7 includes a motor 14, a drive shaft 15 to which the rotation of the motor 14 is transmitted,
The clutch includes a meshing clutch that transmits rotation of the drive shaft to the shaft, and a shaft that engages with the lower rotor.
The motor 14 is fixed to the lower center of the case 4. The rotation of the motor shaft is transmitted to the drive shaft 15 via a gear 16 (not shown). A flange plate 18 is fixed to an upper portion of the drive shaft 15. A nail is provided on the upper surface of the flange plate 18. The mandrel 13 is mounted on the upper surface of the flange plate 18. Mandrel flange plate 13a also at the bottom of mandrel 13
Are integrally formed. The lower surface of the mandrel flange plate 13a is also provided with a pawl. The pawl provided on the upper surface of the flange plate 18 and the pawl provided on the lower surface of the mandrel flange plate 13a are engaged with each other to transmit the rotation of the drive shaft 15 to the mandrel 13.
Since the lower rotor 6 rotates together with the mandrel 13, the rotation of the motor 14 drives the lower rotor 6 to rotate.

A leaf spring 25 is fixed around the flange plate 18. The leaf spring 25 abuts one end of the lower rotor 6, to urge the lower rotor 6 upward by elastic force. Leaf spring 2
The elastic force of 5, the lower rotor 6 is in close contact with the upper rotor 5. The rotation of the upper rotor 5 is restricted by the upper rotor support plate 12. By providing the leaf spring 25, it is possible to relatively rotate the upper rotor 5 and the lower rotor 6 while applying pressure between the upper rotor 5 and the lower rotor 6.

The receiving tray 9 is provided around the outer periphery of the lower rotor 6. A scraping blade 19 is provided on a side surface of the lower rotor 6. By the rotation of the lower rotor 6, the powdered tea stored in the tray 9 is raked and stored in the cup 2.

FIG. 8 shows the state of pulverization of tea leaves between the upper rotor 5 and the lower rotor 6. The tea leaves put in from the supply port 23 of the upper rotor 5 enter between the upper rotor 5 and the lower rotor 6. Since the flat portion 6a formed on the facing surface of the lower rotor 6 is dented, a gap 34 is provided between the flat portion 5a of the upper rotor 5 and the flat portion 6a of the lower rotor 6.
Occurs. This gap 34 is formed by the tapered portions 5b, 6b
It becomes narrower toward. By generating the gap 34, the grooves 20 and 21 formed in the upper rotor 5 and the lower rotor 6
And the grooves 30 and 31 formed in the holes do not cause galling. When the lower rotor 6 rotates, the main groove 20 formed in the upper rotor 5 and the main groove 30 formed in the lower rotor 6 coincide each time the lower rotor 6 rotates 45 degrees. The upper rotor 5
Sub groove 21 formed in lower rotor 6 and sub groove 3 formed in lower rotor 6
1 intersect each other at an acute angle. The supplied tea leaves are
The main grooves 20, 30 or the sub grooves 21, 31 are filled and pulverized by receiving a shearing force. Since the sub-grooves 21 and 31 intersect at an acute angle, the pulverized material is centrifuged by the shearing action. Since the gap 34 is narrowed toward the tapered portions 5b and 6b on the periphery, the taken tea leaves are
Grain size is gradually reduced and moves toward the periphery. Since the tapered portion 5b and the tapered portion 6b rub against each other in close contact with each other, the crushed material centrifuged and moved from the flat portions 5a, 6a to the tapered portions 5b, 6b between the tapered portions 5b and 6b. , Can be finely pulverized. Further, since the flat portions 5a and 6a are formed substantially flat, the time during which the crushed material stays between the flat portions 5a and 6a is short.

In the flat portions 5a and 6a, the particle size of the tea leaves is gradually reduced, so that the tea leaves are easily pulverized by the tapered portions 5b and 6b. Further, since the tapered portions 5b and 6b are inclined upward toward the outer periphery, the time during which tea leaves stay in the tapered portions 5b and 6b can be extended. Therefore, the grains can be reliably pulverized, and the particle size of the pulverized powdered tea can be kept constant. Also, the plane portions 5a,
6a is formed substantially flat, so that the pulverized material
The residence time during 6a is short. For this reason, the total crushing time can be shortened as compared with the case where a conventional mortar-shaped mortar is used. Further, since a constant pressure is applied to the tapered portions 5b and 6b by the elastic force of the leaf spring 25, powdered tea having a small variation and a constant particle size can be obtained.

FIG. 9 shows another example of the upper rotor 5 and the lower rotor 6. Inside the respective tapered portions 5b, 6b of the upper rotor 5 and the lower rotor 6, horizontal portions 5c, 6c orthogonal to the rotation center A of the lower rotor 6 are smoothed similarly to the tapered portions 5b, 6b. It is formed. The flat portions 5a and 6a are formed inside the horizontal portions 5c and 6c. According to the present invention, the horizontal portions 5c and 6c are also closely contacted and rubbed in the same manner as the tapered portions 5b and 6b. Can be finely pulverized, so that the pulverized material can be more finely pulverized.

Further, by using a ceramic material mainly composed of alumina for the upper rotor 5 and the lower rotor 6, high strength can be achieved, and the thickness of the upper rotor 5 and the lower rotor 6 can be reduced. By making the upper rotor 5 and the lower rotor 6 thin,
The upper rotor 5 and the lower rotor 6 having excellent heat radiation characteristics can be obtained.
For this reason, the temperature of the upper rotor 5 and the lower rotor 6 can be prevented from rising during the pulverization, and the pulverization can be performed without losing the aroma, flavor, etc. of the tea.

FIG. 9 is a graph showing the particle size distribution of the ground tea powder. The horizontal axis represents the particle size (μm) on a logarithmic scale,
The vertical axis represents the frequency (%) and the cumulative frequency (%). 6
A 600 μm sieve was measured using a 00 μm sieve. In the sample diagram, (A) shows the particle size distribution of the powdered tea using the grinder of the present invention, and (B) shows the particle size distribution of the powdered tea using the conventional mortar-shaped powdering machine.
The particle size distribution of the powdered tea of sample (A) is the same as that of sample (B)
Particle size distribution of powdered tea. Also, sample (A)
Has a frequency peak at about 100 μm.
Therefore, according to the powder grinder of the present invention, even if the pulverization time is shortened, powdered tea having a fine particle size can be obtained in substantially the same manner as powdered tea using a conventional mortar-shaped powder grinder. Also, 1
Since it has a frequency peak at about 00 μm, powdered tea with a constant particle size can be obtained. The weight ratio of the powdered tea having a particle size of 600 μm or more was 4 for the sample (B).
At 2%, sample (A) is 0.9%. According to the grinding machine of the present invention, powdered tea having a large particle size of 600 μm or more can be reduced.

[0031]

As described above, according to the present invention, a flat portion formed substantially flat and a tapered portion formed on the periphery of the flat portion are formed on the opposing surfaces of the upper mill and the lower mill. With the upper mill and the lower mill each of the flat portion and the tapered portion, since a groove is formed only in the flat portion, when the upper mill and the lower mill are relatively rotated, grains and the like, Due to the grooves formed in the planes of the upper mill and lower mill, they are sheared and roughly crushed. Then, the pulverized material is centrifuged. Since the tapered portion is formed on the periphery of the flat portion of the upper mill and the lower mill, the tapered portions are in close contact with each other and rub. Therefore, the pulverized material can be finely pulverized between the tapered portions of the upper mill and the lower mill. Further, since the flat portion is formed substantially flat, the time during which the crushed material stays between the flat portions is short. Therefore, the total crushing time can be shortened as compared with the case where a conventional mortar-shaped mortar is used.

[Brief description of the drawings]

FIG. 1 is an external view showing a grinding machine according to an embodiment of the present invention.

FIG. 2 is a sectional view of the milling machine.

FIG. 3 is a sectional view of an upper rotor.

FIG. 4 is a bottom view of the upper rotor.

FIG. 5 is a sectional view showing a groove.

FIG. 6 is a sectional view showing a lower rotor.

FIG. 7 is a plan view of a lower rotor.

FIG. 8 is a sectional view showing an upper rotor and a lower rotor.

FIG. 9 is a sectional view showing another example of the upper rotor and the lower rotor.

FIG. 10 is a graph showing a particle size distribution.

[Explanation of symbols]

 5 Upper mill (upper rotor) 6 Lower mill (lower rotor) 5a, 6a Planar portion 5b, 6b Tapered portion 5c, 6c Horizontal portion 25 Elastic body (leaf spring)

Claims (4)

(57) [Claims] 1. A milling machine for grinding a grain or the like by causing an upper mill and a lower mill to face each other and rotating the upper mill and the lower mill relatively to each other, wherein the upper mill and the lower mill are Each of the opposing surfaces includes a flat portion that is formed substantially flat, and a tapered portion that is formed on the periphery of the flat portion, and among the flat portion and the tapered portion of the upper mill and the lower mill, A groove is formed only in the flat portion, and a gap generated between the upper mill and the lower mill is formed in the flat portion.
The top is gradually narrowed from the center to the outer circumference.
At least one of the flat part of the mill or the lower mill is
The upper mill taper and the lower mill taper are brought into close contact with each other.
Miller machine, characterized in that that. 2. A horizontal portion orthogonal to the rotation center of the upper mill or the lower mill is provided inside each of the tapered portions of the upper mill and the lower mill, and the flat portion is formed inside the horizontal portion. The milling machine according to claim 1 , wherein the milling machine is formed. 3. A process according to claim, characterized in that tilting the tapered portion upward toward the outer periphery of the tapered portion 1 or
3. The grinding machine according to 2. 4. A miller machine according to any claim 1 to 3, characterized in that the the upper die and the lower die, is brought into close contact by the elastic force of the elastic body.