JPH06114254A - Dispersing mixer - Google Patents

Abstract

PURPOSE:To provide a dispersing mixer of simple construction which is an Amula type dispersing mixer equipped with a cylindrical rotor and where a granular medium, such as beads is prevented from being one-sidedly concentrated on the outlet side, being pushed by the flow of the medium even if the quantity of the medium passing through a crushing chamber is increased and the stable operation is performed without restricting the rotor and the short pass of the medium is prevented to perform the advanced dispersing treatment. CONSTITUTION:The ratio of the length L of a cylindrical rotor 2 to the diameter D of the rotor is taken to be L/D<1. And simultaneously a ring crushing zone 4 formed between the outer peripheral surface of the rotor 2 and the inner peripheral surface of a vessel 1 is provided with a medium short pass preventive means for preventing the medium from passing though the shortest distance of the ring crushing zone 4 by plural ring grooves 2b formed on the outer peripheral surface of the rotor, etc.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is used in the field of manufacturing paints and chemicals, and is a raw material [medium] for solvents, pigments and other additives.
The present invention relates to a dispersion stirrer using a cylindrical stirring blade called an Amura type mill, which is used for stirring and dispersing with a granular medium such as glass or steel.

[0002]

2. Description of the Related Art Conventionally, what is called an amueller type mill, a dispersion stirrer equipped with a rotor composed of cylindrical stirring blades is used in place of a rotor generally equipped with a plurality of disk shaped stirring blades. It is used. Compared to the conventional dispersion stirrer, the crushing zone is limited to the outer circumference of the cylindrical rotor, so that the shearing force inside the stirrer is almost uniform, and the particle size in the product mill base (hereinafter referred to as the medium) is small. Is uniformized, and the particle size distribution is said to be narrower and sharper than in the past.

[0003]

Since the volume of the crushing chamber is limited to the outer peripheral portion of the rotor in the above-mentioned amueller type mill, its cross-sectional area is much smaller than that of the conventional machine, and therefore, the crushing chamber outlet side is reduced. Since the flow velocity of the medium is increased, the medium (hereinafter referred to as medium) is pressed against the exit side of the crushing chamber, and there is a drawback that the rotor is easily restrained. In order to make up for this drawback, in a ball mill for an amuller type agitator described in Japanese Patent Publication No. 62-43731, a medium, which is a crushing ball, is fed into an agitator together with a medium of a raw material during the operation of the machine, and a separate machine separates A method of separating the medium and the medium is adopted. However, this method inevitably complicates the device, and it is considered difficult to deal with high-viscosity products (such as paints and inks). Further, in order to make up for the above-mentioned drawbacks, a ball mill having a W-shaped vertical cross-sectional shape and provided with a medium return passage from the crushing chamber outlet side to the crushing chamber inlet side (Japanese Patent Laid-Open No. Sho 6-62).
No. 1-136447) is also devised. In this case, if the return path of the medium is made sufficiently large, there is a possibility that a short path may occur in which the medium is discharged without being sufficiently crushed through the return path, and the return path is not so wide that the path is not sufficiently wide. There is a risk of being blocked by.

The present invention has been made in view of the above points, and is an amueller type dispersion stirrer equipped with a cylindrical rotor, in which the granular medium is a medium even if the amount of medium passing through the grinding chamber is increased. It is possible to operate without restricting the rotor by preventing it from being unilaterally concentrated on the outlet side due to being pushed by the flow, and to perform a high-level dispersion treatment with a uniform crushed particle size by preventing a short pass of the medium. It is an object of the present invention to provide a dispersion stirrer that can be used.

[0005]

In order to achieve the above object, according to the present invention, a rotor 2 having a cylindrical outer peripheral surface such that an annular crushing zone 4 is formed between the inner peripheral surface of the vessel 1 and the inner peripheral surface of the vessel 2. Is fixed to the stirring shaft 3 and is a dispersion stirrer that stirs the medium supplied into the vessel 1 together with the medium and discharges the dispersed medium out of the machine as a rotor diameter D and a rotor length. The ratio with L is 1 ≦ L / D <3
L / D contrary to the conventional large and small ratio
In addition to being formed in <1, the annular crushing zone 4 is provided with a short path preventing means for preventing the medium from passing the shortest distance of the annular crushing zone 4 on the outer circumference of the rotor.

It is effective that the medium short-pass preventing means is provided by forming a plurality of annular grooves 2b on the outer peripheral surface of the rotor 2.

Further, as a medium short-pass preventing means, a plurality of pins 2c and 1c are arranged on the outer peripheral surface of the rotor 2 and the inner peripheral surface of the vessel 1 at predetermined intervals so as to be alternately located in the axial direction. It can also be used by projecting.

When forming the annular crushing zone 4, at least the outer peripheral surface of the rotor 2 is formed into a cylindrical shape or a frustoconical shape in which the diameter of the medium outlet side is slightly larger than the diameter of the inlet side. The gap width of the annular crushing zone 4 may be the same on the medium inlet side and the medium outlet side, or may be slightly wider on the medium outlet side than on the medium inlet side.

Furthermore, when the annular groove 2b is formed on the outer peripheral surface of the rotor 2, the gap width of the annular crushing zone 4 is such that the interval between the convex portion of the outer peripheral surface and the inner peripheral surface of the bezel 1 is the filling medium diameter. 5
It is desirable to set it up to 20 times.

[0010]

In the dispersion stirrer configured as described above, as long as the volume of the annular grinding zone around the outer circumference of the cylindrical rotor is limited, the rotor diameter is reduced by the length of the grinding chamber which is shorter than that of the Amura type mill of the same volume. L / D <1 due to the larger cross-sectional area of the annular grinding zone.
The flow velocity of the medium can be set to 1/4 to 1/6 depending on the ratio of, and the granular medium can be operated without being biased toward the outlet side by being pushed by the flow velocity of the medium. Further, since the length of the crushing chamber is shortened, the circulation of the medium in the crushing zone is smooth, and the medium is prevented from unilaterally concentrating on the outlet side. In this case, since the rotor diameter became large, the density of the medium in the pulverization zone was sufficiently increased by the centrifugal force even if the filling rate of the medium was lowered. You can Further, since the filling rate becomes low, the power at the time of starting can be kept low, and the influence of the reduction of the filling rate due to the abrasion of the medium is reduced. Furthermore, as the rotor diameter increases,
Since the distance between the annular grinding zone and the medium separation mechanism on the medium outlet side can be maintained, damage to the gap separator or the separation screen due to the medium can be suppressed.

In the present invention, the medium short-pass preventing means is provided in the annular crushing zone on the outer circumference of the rotor to prevent the medium from passing the shortest distance of the crushing zone. Even if the length is shorter than the conventional one, sufficient dispersion treatment is performed while the medium passes through the pulverization zone, and the pulverized particle size can be made uniform.

When a plurality of annular grooves 2b are provided on the outer peripheral surface of the rotor 2 as the above-mentioned short-pass preventing means, the centrifugal force received by the medium contacting the convex portion on the outer peripheral surface of the rotor 2 and the annular groove 2b are formed. Since a difference occurs between the centrifugal force received by the medium in contact with the medium, a plurality of annular convection vortices can be forcibly generated in the medium passing through the annular crushing zone between the inner peripheral surface 1a of the Bethel and the rotor 2. The medium uniformly flows while the flow direction fluctuates back and forth, and short paths can be effectively prevented (see FIG. 2).

Further, as the short-pass prevention means,
When a plurality of pins 2c, 1c are provided on the outer peripheral surface of the rotor 2 and the inner peripheral surface of the vessel 1 so as to be alternately located at predetermined intervals in the axial direction, the medium passes through the annular grinding zone 4. The pins 2c and 1c that intersect with each other effectively move while being agitated to effectively prevent a short pass.

Further, by forming the outer peripheral surface of the rotor 2 into a frustoconical shape in which the diameter on the outlet side of the medium is slightly larger than the diameter on the inlet side, centrifugal force is applied to the medium as the medium flows to the outlet side. The force is increased, the crushing effect by the medium is increased, and the dispersion can be effectively performed. Further, if the gap width of the annular crushing zone 4 is made slightly wider on the outlet side than on the medium inlet side, it is possible to prevent the risk that the medium will block the flow of the medium on the outlet side.

When the gap between the convex portion on the outer peripheral surface of the rotor 2 and the inner peripheral surface of the vessel 1 is set as the gap width of the annular crushing zone 4, the gap is a filling medium diameter (usually 1 m / m).
m φ to 2 m / m φ) is 5 to 20 times, and the magnification is appropriately determined according to the product specifications such as the medium diameter, the viscosity of the medium and the particle size to be crushed. Generally, the lower the magnification, the more uniform the crushing. The dispersion effect can be improved.

[0016]

Embodiments of the dispersion stirrer of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a dispersion stirrer for an amura type mill according to the present invention having a horizontal vessel. As shown in the figure, the cylindrical bezel 1 having a horizontal axis has a large diameter and a short length corresponding to the rotor 2 arranged in the bezel. jacket is a jacket ₈₁ is also in the side wall 1 _2, 1 ₃ of the end surfaces
8 ₂ and 8 ₃ are provided, and cooling water is introduced from the water supply ports 11 ₁ and 11 ₂ respectively and discharged from the discharge ports 12 ₁ and 12 ₂ to prevent cooling, that is, the temperature rise of the inner wall of the vessel. The rotor 2 in Bethel 1 is rotatably supported by the bearing portion 1 _4, which is secured through the hollow tubular section 1 ₃ 'to the side wall 1 ₃ medium outlet side of the stirring shaft 3 which is fixed to the rotor 2 is Bethel It is arranged on the central axis of the vessel 1 and is rotationally driven by an external power (not shown). Then, the supply port 5 of the medium as an opening in the side wall 1 ₂ central Bethel central axis of the medium introduction side of Bethel 1 is attached to the side wall 1 _2, the medium outlet side wall 1 ₃ central Bethel central axis of anchored the hollow tubular section 1 ₃ on a line 'on top, is attached the outlet 6 of commercialization was medium, the hollow tubular section 1 _3' to the outlet of the medium from the hollow portion of Bethel 1 at the base of the medium A gap separator 10 is provided so as to surround the stirring shaft 3 as a separator of
The crushed and agitated medium is separated from the granular medium.

The rotor 2 is a hollow cylindrical member fixed to the shaft end of a hollow stirring shaft 3 to enhance the effect of cooling with cooling water. The rotor diameter D and the rotor length L are The ratio of L / D <1 is a preferable value of L / D≈1 /
Manufactured in 2. The gap width g between the inner peripheral surface 1a of the vessel 1 and the outer peripheral surface of the rotor 2 is set to an arbitrary value between 5 and 20 times the medium diameter depending on the medium diameter, the viscosity of the medium, the particle size to be crushed, and the like. together is set, a medium holding a predetermined gap is adapted to flow smoothly between the side walls 1 _2, 1 ₃ of Bethel facing the end surfaces of the rotor 2. Further, the outer peripheral surface of the rotor 2 has a plurality of annular grooves of a predetermined width and a predetermined depth.
2b is provided, and a plurality of annular convection vortices are generated due to the difference in centrifugal force received by the medium in contact with the convex and concave annular grooves 2b on the outer peripheral surface, and the grinding zone 4 is set at the shortest distance where the medium is not sufficiently dispersed. It is designed to prevent short passes that pass through (see Fig. 2).

Further, a water supply pipe 7 for a rotor having a predetermined small diameter is provided on the central axis of the hollow stirring shaft 3 so as to extend to a predetermined position in the hollow portion of the rotor. The rotor is also cooled with cooling water and the stirring shaft 3
The inside is refluxed to prevent the heat of the medium from rising.

In the above-mentioned amueller type disperser, when manufacturing paints, chemicals, etc., 50% to 80% of the apparent volume of the grinding chamber is filled in the vessel 1 with a medium such as beads, and the rotor is centrifuged during operation of the machine. The force concentrates the medium on the outer periphery of the crushing chamber (annular crushing zone 4) so that the medium does not remain in the gap separator 10 of the medium separating device. Then, raw materials such as pigments, solvents, and other additives, that is, a medium is charged into the vessel 1 through the inlet 5 and the rotor 2 is rotated at a predetermined speed, and cooling water is circulated in both the vessel and the rotor to raise the temperature of the medium. The medium is dispersed and agitated while preventing it, and the medium is dispersed and separated from the medium by a gap separator, and only the medium is discharged as a product.

In this case, the ring-shaped crushing zone 4 formed by the outer circumference of the rotor and the inner circumference of the bezel has a length shorter than the diameter of the conventional amura type, but is shorter than the diameter. Since the cross-sectional area increases as the diameter of the minute rotor increases, the passage velocity of the medium becomes 1/4 to 1/6, which is much slower than the conventional one, and the medium is pushed by the velocity of the medium and is displaced toward the outlet side. In addition, the multiple annular grooves on the outer circumference of the rotor cause an annular convection vortex in the medium, and the crushed particle size can be made uniform without the risk of short-pass, and the damage to the gap separator is reduced, which is stable. Thus, the dispersion processing of the medium can be smoothly performed.

FIG. 3 shows another embodiment of the amueller type dispersing machine of the present invention, in which the vessel is vertical type and the medium short path preventing means is different from that described above. In the dispersion stirrer, the ratio of the diameter D of the rotor to the length L of the rotor is almost the same as that of the above-mentioned embodiment, but the gap width between the outer peripheral surface 2a of the rotor and the inner peripheral surface 1a of the vessel is slightly larger than that of the above-mentioned embodiment. Widely formed, the medium is introduced into the vessel through the inlet 5 at the bottom of the vessel, and the ring-shaped crushing zone 4
The medium, which is a product that has been crushed by the above and separated from the medium by the gap separator 10, is discharged from the upper discharge pipe 6. Further, the cooling of the vessel by the jackets 8 ₁ , 8 ₂ , 8 ₃ and the rotor 2 by the water supply pipe 7 passing through the stirring shaft 3
Is also cooled in the same manner as in the above-mentioned embodiment.

In this embodiment, a plurality of pins 2c and 1c each having a predetermined diameter and a predetermined height are arranged on the outer peripheral surface 2a of the rotor 2 and the inner peripheral surface 1a of the bezel 1 in the axial direction at predetermined intervals. They are planted so that they are located alternately. As a result, the medium is conveyed while being agitated by the pins 2c and 1c which intersect with each other while being introduced from the introduction port 5 and passing through the annular grinding zone 4, so that the dispersion treatment is performed without causing a short path, and the gap separator 10 is formed. Only the product medium is discharged through the discharge pipe 6.

FIG. 4 shows an amueller type dispersing machine according to still another embodiment of the present invention, in which the vessel has a vertical type and the rotor and the vessel each have a frustoconical shape in which the diameter on the outlet side of the medium is slightly larger than the diameter on the inlet side. A dispersion stirrer shaped into a shape is shown. In the dispersion stirrer, the ratio of the diameter D on the large side of the rotor to the length L of the rotor is L / D≈, as in the above-mentioned embodiment.
It is manufactured in 1/2 and the outer peripheral surface of the frusto-conical rotor 2 has a plurality of annular grooves 2b with a predetermined width and a predetermined depth. When the medium is subjected to centrifugal force by the rotational force of the rotor formed on the outer peripheral surface of the rotor, a plurality of annular convection vortices are favorably generated. Further, the interval between each convex portion on the outer peripheral surface of the rotor and the inner peripheral surface of the bezel is constant, that is, the gap widths of the medium inlet side and the outlet side of the annular pulverization zone 4 are formed to have the same size. Then, the medium is introduced through the inlet 5 at the bottom of the vessel,
In the frustoconical annular crushing zone 4, the mixture is stirred and dispersed, and only the medium, which is the product, is discharged from the discharge pipe 6 through the gap separator 10 as in the above embodiment.

When the rotor is frustoconical as described above, the centrifugal force applied to the medium and the medium increases as the medium moves toward the outlet side, the crushing effect of the medium is increased, and the dispersion treatment can be efficiently performed. . In this case, not only the medium conveyed upward, but also the medium tends to move upward due to the centrifugal force increasing toward the upper part of the outer circumference of the rotor. By appropriately selecting the rotation speed of the rotor from the point of being as slow as 1/4 to 1/6, it is possible to prevent the blockage due to the rise of the medium above the grinding zone.

In the embodiment shown in FIG. 5, the gap width of the annular crushing zone 4 of the dispersion stirrer shown in FIG. 4 is set so that the gap width g ₁ on the inlet side of the lower medium is larger than the gap width g ₂ on the outlet side of the upper medium. Rather wide
It is formed so that g ₂ > g ₁ . In this case, when the medium is dispersed and stirred, even if the medium tends to rise, the void width becomes wider toward the upper portion, so that there is an effect of preventing blockage due to the rise of the medium at the upper portion. Therefore, the rotational speed of the rotor can be increased slightly from that shown in FIG. 3 to efficiently perform the dispersion processing. In these dispersion stirrers, the portions of the rotor and the bezel facing the annular crushing zone may be made of wear-resistant material such as hardened steel, cemented carbide, ceramic, rubber lining, and plastic.

In the above embodiment, in providing the short-pass prevention means in the annular crushing zone 4, a plurality of annular grooves 2b are formed on the outer peripheral surface of the rotor 2, or the outer peripheral surface 2a of the rotor 2 and the vessel 1 are formed. Although a plurality of pins 2c and 1c are provided so as to be alternately positioned in the axial direction on the inner peripheral surface 1a of the pin with a predetermined gap therebetween, this is formed, but it is possible to prevent a short path during dispersion processing of the medium. If necessary, it is possible to form arbitrarily, for example, to form annular grooves of appropriate dimensions only on the inner peripheral surface of the bezel, or to arrange annular grooves alternately on the outer peripheral surface of the rotor and inner peripheral surface of the bezel in the axial direction. May be installed in
Of course, various modifications can be made without departing from the scope of the present invention.

[0028]

According to the dispersion stirrer of the present invention as set forth in claim 1, in an amuler type dispersion stirrer in which a cylindrical rotor is provided in a vessel and an annular crushing zone is provided, the annular crushing zone is the same as the conventional one. Compared with the capacity type, the cross-sectional area can be increased and the flow velocity can be reduced to 1/4 to 1/6, and the granular medium is pushed by the flow velocity of the medium and concentrated unilaterally on the outlet side. It does not restrain the rotor and restrains the rotor and prevents the medium from being carried without being sufficiently crushed by the short-pass preventing means provided in the annular crushing zone, and crushes the crushed particles uniformly to a good crushing size. It does not require a separate machine to separate the medium from the conventional amura type mill, and the structure does not become complicated, and the return path of the medium is different from the one having a grinding chamber with a W-shaped cross section. Short at There is no fear of such clogging of the scan and the passage, it is possible to provide a simple dispersion stirrer structure capable of performing stable high-level distributed processing. Further, by increasing the centrifugal force by increasing the rotor diameter, it is possible to sufficiently increase the density of the medium in the crushing zone and to disperse favorably, without increasing the filling rate of the medium as in the conventional case. Further, since the filling rate is low, the power required for starting is low, and there is an advantage that the influence of the reduction of the filling rate due to the abrasion of the medium is reduced. Further, since the distance between the annular crushing zone and the medium separation mechanism can be set, damage to the gap separator and the screen by the medium can be reduced.

According to the second aspect of the present invention, by performing a simple process on the outer peripheral surface of the rotor, it is possible to effectively form the medium short path preventing means.

According to the third aspect of the present invention, the short-path preventing means capable of preventing the short-path of the medium while enhancing the stirring effect can be easily formed by the pins intersecting with each other.

According to the invention described in claim 4, a standard type dispersion stirrer can be easily formed.

According to the fifth aspect of the present invention, by using the frustoconical rotor, the crushing effect of the medium of the medium can be enhanced and the dispersion treatment can be efficiently performed.

According to the invention described in claim 6, the annular crushing zone can be easily formed.

According to the seventh aspect of the present invention, it is effective in preventing the medium from being blocked by the medium on the outlet side of the annular grinding zone, and is particularly advantageous when a frustoconical rotor is used.

According to the eighth aspect of the invention, the gap width is appropriately selected from the range of 5 to 20 times the diameter of the filling medium depending on the viscosity of the medium to be dispersed, the particle size to be pulverized, etc. It can be performed.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a horizontal dispersion stirrer according to the present invention,

2 is a principle view showing a state in which a convection vortex is generated by an annular groove on the outer circumference of the rotor in the annular crushing zone shown in FIG. 1 to prevent a short path of a medium;

FIG. 3 is a vertical sectional side view of a vertical type dispersion stirrer according to another embodiment of the present invention;

FIG. 4 is a vertical sectional side view of a vertical type dispersion stirrer according to still another embodiment of the present invention;

5 is a vertical sectional side view showing a modified example of the void width of the annular pulverization zone in the dispersion stirrer of the type shown in FIG.

[Explanation of symbols]

1 ... Bethel, 1a ... Bethel inner peripheral surface, 1c ... Pin, 2 ...
Rotor, 2a ... Rotor outer surface, 2b ... Annular groove, 2c
... pin, 3 ... stirring shaft, 4 ... circular grinding zone, 5 ... inlet, 6 ... outlet, 7 ... water supply pipe for the rotor, 8 _1,
8 ₂ , 8 ₃ ... Jacket, 10 ... Separator (gap separator), 11 ₁ , 11 ₂ ... Water supply port, 12 ₁ , 12 ₂ ... Drainage port,
D ... outer diameter of rotor, L ... length of rotor, g ...
Void width, g ₁ … Inlet void width, g ₂ … Exit void width.

Claims (8)

[Claims] 1. A rotor 2 having a cylindrical outer peripheral surface is fixedly attached to a stirring shaft 3 so as to form an annular crushing zone 4 between the inner peripheral surface of the vessel 1 and the inner peripheral surface of the vessel, and the rotor 2 is fixed in the vessel 1. In a dispersion stirrer which stirs the supplied medium together with the medium and discharges the dispersion-treated medium out of the machine, the ratio of the diameter D of the rotor to the length L of the rotor is set to L / D <1, and the medium is A dispersion stirrer, characterized in that a short-pass preventing means for preventing the oil from passing through the shortest distance of the annular grinding zone 4 on the outer periphery of the rotor is provided in the annular grinding zone 4. 2. The dispersion stirrer according to claim 1, wherein the medium short-pass preventing means is a plurality of annular grooves 2b formed on the outer peripheral surface of the rotor 2. 3. A medium short-pass preventing means comprises a plurality of pins 2c, which are provided on the outer peripheral surface of the rotor 2 and the inner peripheral surface of the vessel 1 so as to be alternately arranged at predetermined intervals in the axial direction, The dispersion stirrer according to claim 1, which is 1c. 4. The dispersion stirrer according to claim 1, wherein the outer peripheral surface of at least the rotor 2 is formed in a cylindrical shape. 5. A dispersion stirrer according to claim 1, 2 or 3, wherein at least the outer peripheral surface of the rotor 2 is formed in a frustoconical shape in which the diameter of the medium on the outlet side is slightly larger than the diameter on the inlet side. . 6. The dispersion stirrer according to any one of claims 1 to 5, wherein the annular crushing zone 4 has the same width on the inlet side and the outlet side of the medium. 7. The annular crushing zone 4 is formed such that the gap width thereof is slightly wider on the outlet side than on the medium inlet side.
The dispersion stirrer according to any one of 1. 8. The annular crushing zone 4 has a gap width of the rotor 2
The dispersion stirrer according to claim 2, wherein the interval between the convex portion on the outer peripheral surface of the container and the inner peripheral surface of the vessel 1 is 5 to 20 times the diameter of the filling medium.