Homogenizer and stirring device

Abstract

This invention provides a homogenizer that adjusts the shear force on the workpiece by the relative axial movement of the stator and rotor, while also solving the problem of short passes. [Solution] At the position where the stator 3b moves to its highest point, the entire stator main region of the first stator peripheral wall 3b2 moves upward away from the rotor main region of the rotor peripheral wall 3c2 and faces the rotor continuous region of the rotor peripheral wall radially. A portion of the workpiece pushed outwards by the rotation of the rotor 3c attempts to flow outwards through the stator penetration portion of the stator main region of the first stator peripheral wall (short path), but this flow of workpiece is blocked by the rotor continuous region that faces the stator main region of the first stator peripheral wall radially. The workpiece pushed outwards flows outwards from the lower end of the second stator peripheral wall 3b3, through the lower end of the first stator peripheral wall, towards the rotor main region of the rotor peripheral wall.

Description

Technical Field

[0001] The present invention relates to a homogenizer used for processing such as mixing, emulsifying, dispersing, and defoaming of objects to be processed such as viscous liquids and powders in the manufacturing processes of pharmaceuticals, cosmetics, battery materials, fine chemicals, foods, etc., and a stirring device equipped with the homogenizer.

Background Art

[0002] For example, homogenizers as described in Patent Documents 1 to 3 are used for performing processes such as mixing, dispersing, emulsifying, and defoaming of objects to be processed. These homogenizers include a stator and a rotor arranged coaxially inside a casing, and promote the mixing, dispersion, emulsification, etc. of the object to be processed through the suction, shearing, and extrusion effects on the object caused by the rotation of the rotor.

[0003] In general, the shearing force of a homogenizer acting on an object to be processed is proportional to the rotation speed of the rotor, provided that the viscosity of the object to be processed and the configuration of the homogenizer (including the clearance between the rotor and the stator) are the same. Therefore, although the shearing force of the homogenizer can be adjusted by adjusting the rotation speed of the rotor, the adjustable range is limited.

[0004] In view of this, in Patent Document 4, the stator and the rotor are configured to be movable along the axial direction, and the shearing force can be adjusted by changing the relative position of the two. That is, in the homogenizer of Patent Document 4, by moving the stator in the axial direction, the homogenizer can be switched between: a high shear mode (Figures 2 and 5) in which the entire range of the stator main region (the region provided with a plurality of through holes) on the stator peripheral wall portion faces the rotor main region (the region provided with a plurality of through holes) on the rotor peripheral wall portion in the radial direction; a low shear mode (Figures 3 and 6) in which the entire range of the stator main region is axially displaced from the rotor main region; and an intermediate shear mode between the high shear mode and the low shear mode.

Prior Art Literature

Patent Literature

[0005] [Patent Document 1] Japanese Patent Publication No. 2024-97131 [Patent Document 2] Patent No. 488866 [Patent Document 3] Japanese Patent Publication No. 2021-115808 [Patent Document 4] Japanese Patent Publication No. 2019-63713 [Overview of the project] [Problems that the invention aims to solve]

[0006] In the homogenizer described in Patent Document 4, a short-path flow of the material to be processed occurs, passing through the homogenizer without being subjected to the shear action of the stator and rotor. Specifically, in the high-shear mode shown in Figure 2 (in-line type) of Patent Document 4, a portion of the material to be processed that is drawn into the center of the homogenizer by the rotation of the rotor 3 escapes to the outer circumference by passing through the gaps between the support columns 44 of the stator 4, without passing through the through holes of the rotor 3 and stator 4. In the high-shear mode shown in Figure 5 (batch type) of Patent Document 4, a portion of the material to be processed that is drawn into the center of the homogenizer by the rotation of the rotor 3 escapes downward from inside the rotor 3 and stator 4 through the through holes 31a of the bottom plate 31. Furthermore, in the low-shear mode shown in Figure 3 (in-line type) of Patent Document 4, a portion of the material to be processed that is drawn into the center of the homogenizer by the rotation of the rotor 3 escapes to the outer circumference by passing through the through holes of the stator 4. In the low-shear mode shown in Figure 6 (batch type) of Patent Document 4, some of the material to be processed, which is drawn into the center of the homogenizer by the rotation of the rotor 3, escapes to the outer circumference through the gaps between the support columns 44 of the stator 4, and also escapes downward through the through holes 31a of the bottom plate 31. For these parts of the material that have been short-passed, the shearing and extrusion actions of the stator and rotor do not act (or are significantly reduced), resulting in the material not being processed uniformly as a whole, causing variations in the quality of the processed product. Furthermore, in order to process the material uniformly as a whole, it becomes necessary to increase the number of times the material is passed through the homogenizer (number of passes), which leads to a decrease in the processing efficiency of the material.

[0007] The object of the present invention is to provide a homogenizer that can adjust the shear force on the workpiece by the relative axial movement of the stator and rotor, and can solve the problem of the workpiece short-passing described above, and a stirring device equipped with the homogenizer. [Means for solving the problem]

[0008] To solve the above problems, the present invention provides a homogenizer comprising a casing, a stator and a rotor arranged inside the casing such that their axes are coaxial, and a moving mechanism for moving the stator and the rotor relative to each other in a direction along the axis, wherein the stator has a stator base and a stator peripheral wall portion extending from the stator base in one direction along the axis, and the stator peripheral wall portion is provided with a stator main region in which a plurality of stator penetration portions that penetrate the stator peripheral wall portion are arranged in the circumferential direction, and the rotor has a rotor base and extends from the rotor base in the other direction along the axis, and is opposite to the stator peripheral wall portion via a predetermined radial clearance A homogenizer is provided having a rotor peripheral wall portion facing a rotor, the rotor peripheral wall portion having a rotor main region in which a plurality of rotor penetration portions penetrating the rotor peripheral wall portion are arranged in the circumferential direction, and a rotor continuous region that is continuous in the circumferential direction from the rotor main region to the end of the rotor peripheral wall portion, and the homogenizer is capable of switching between a state in which the entire range of the stator main region faces the rotor main region in the radial direction, a state in which a part of the stator main region faces the rotor main region in the radial direction and the other range of the stator main region faces the rotor continuous region in the radial direction, and a state in which the entire range of the stator main region faces the rotor continuous region in the radial direction, by the relative movement of the stator and the rotor. [Effects of the Invention]

[0009] According to the present invention, a homogenizer can be provided that can adjust the shear force on the workpiece by the relative axial movement of the stator and rotor, and can also solve the problem of the workpiece short-passing described above, as well as a stirring device equipped with the homogenizer. [Brief explanation of the drawing]

[0010] [Figure 1] This is a longitudinal cross-sectional view showing the overall configuration of the stirring device according to the embodiment. [Figure 2A]It is an enlarged cross-sectional view showing the periphery of the homogenizer, showing a state where the stator of the homogenizer has moved to the lowest position (lowermost position). [Figure 2B] It is an enlarged cross-sectional view showing the periphery of the homogenizer, showing a state where the stator of the homogenizer has moved to the highest position (uppermost position). [Figure 3A] It is a view of the stator viewed from the outer peripheral side. [Figure 3B] It is a perspective view of the stator viewed from obliquely downward. [Figure 3C] It is a view of the peripheral wall portion of the stator viewed from below. [Figure 3D] It is a view of the stator viewed from above. [Figure 4A] It is a view of the rotor viewed from the outer peripheral side. [Figure 4B] It is a perspective view of the rotor viewed from obliquely upward. [Figure 4C] It is a view of the rotor viewed from above. [Figure 5] It is a view of the combined state of the peripheral wall portion of the stator and the peripheral wall portion of the rotor, viewed from above. [Figure 6A] It is a diagram showing a state where the stator has moved to the lowest position (lowermost position). [Figure 6B] It is a diagram showing a state where the stator has moved to an arbitrary position between the lowermost position and the uppermost position (intermediate position). [Figure 6C] It is a diagram showing a state where the stator has moved to the highest position (uppermost position). MODE FOR CARRYING OUT THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0012] FIG. 1 is a longitudinal sectional view showing the overall configuration of a stirring device according to an embodiment. The stirring device of this embodiment is mainly composed of a stirring tank for accommodating an object to be processed, a stirring blade provided inside the stirring tank, and a homogenizer attached to the bottom of the stirring tank. The stirring tank, the stirring blade and the homogenizer have a common central axis X extending in the vertical direction. Hereinafter, the direction along the axis X is referred to as the axial direction X, one direction of the axial direction X is referred to as the upward direction, and the other direction of the axial direction X is referred to as the downward direction.

[0013] A circulation pipe is connected to a side portion of the homogenizer and a side portion of the stirring tank, and a discharge pipe is connected to a part of the circulation pipe via an openable and closable discharge valve. Further, a baffle is fixedly arranged inside the stirring tank.

[0014] The stirring blade is composed of a rotary drive shaft rotatable around the axis X, and a blade portion provided on the rotary drive shaft. A scraper for scraping off the object to be processed adhering to the inner wall of the stirring tank is attached to the blade portion. The rotary drive shaft is rotationally driven around the axis X by a drive motor (not shown), and the blade portion rotates along with the rotation of the rotary drive shaft, whereby the object to be processed in the stirring tank is stirred.

[0015] In this embodiment, the rotary drive shaft 2a is formed in a hollow shaft shape, and a raw material supply pipe 7 is inserted inside it along the axis X of the rotary drive shaft 2a. The upper end of the raw material supply pipe 7 (not shown) communicates with a raw material input section (not shown), such as a hopper, located above and outside the stirring tank 1, and the lower end of the raw material supply pipe 7 extends downward through the lower end of the rotary drive shaft 2a, facing the center of the homogenizer 3 with a predetermined gap between them. Raw materials (powder, liquid, mixtures thereof, etc.) introduced into the raw material supply pipe 7 from a raw material input section (not shown) descend inside the raw material supply pipe 7 and are supplied directly above the center of the homogenizer 3, and are sucked into the center of the homogenizer 3 as the homogenizer 3 (rotor 3c) rotates. Raw material is introduced into the stirring tank 1 via the raw material supply pipe 7 when the raw material is initially introduced into the stirring tank 1, or when additional raw materials are introduced into the material being processed in the stirring tank 1. The raw material supply pipe 7 may rotate together with the rotary drive shaft 2a, or it may not rotate. A feed vane 8 is provided at the lower end of the rotary drive shaft 2a. The rotation of this feed vane 8 causes the material to be processed in the agitated tank 1 to be pumped downwards.

[0016] Figures 2A and 2B are enlarged cross-sectional views showing the peripheral area of ​​the homogenizer 3. Figure 2A shows the state in which the stator 3b of the homogenizer 3 is moved to its lowest position, and Figure 2B shows the state in which the stator 3b of the homogenizer 3 is moved to its highest position.

[0017] The homogenizer 3 comprises a casing 3a, a stator 3b and a rotor 3c arranged inside the casing 3a such that their axes are coaxial, a moving mechanism 3d that moves the stator 3b and the rotor 3c relative to each other in the axial direction X, and a rotational drive unit 3e that rotates the rotor 3c. A connecting pipe 3a1 is fixed to the side of the casing 3a, to which one end of the circulation pipe 4 is connected. The axes of the casing 3a, the stator 3b, the rotor 3c, and the rotational drive unit 3e are coaxial with axis X. In this embodiment, the rotor 3c is fixed in position in the axial direction X, and the stator 3b is movable in the axial direction X.

[0018] The rotary drive unit 3e comprises a drive unit casing 3e1 connected to the bottom of the casing 3a, a rotary drive shaft 3e2 rotatably supported by rolling bearings or the like on the drive unit casing 3e1, and a rotary drive source 3e3 such as an electric motor that supplies rotational power to the rotary drive shaft 3e2. The rotary drive shaft 3e2 is coupled to the rotor 3c. The rotary drive source 3e3 is connected to the rotary drive shaft 3e2 via a transmission mechanism such as a chain and sprocket or a belt and pulley, or is directly connected to the rotary drive shaft 3e2.

[0019] The moving mechanism 3d is composed of, for example, one or more actuation pins 3d1 coupled to the stator 3b, and a linear actuator 3d2, such as an electric cylinder, which actsuates the actuation pins 3d1 in the axial direction X. In the example shown in the figure, the upper ends of the multiple actuation pins 3d1 are coupled to the stator 3b, and the lower ends of the multiple actuation pins 3d1 are coupled to a connecting plate 3d3. Each actuation pin 3d1 extends in the axial direction X, passes through the upper wall portion 3e11 of the drive unit casing 3e1 and the bottom wall portion 3a2 of the casing 3a from the connecting plate 3d3 to the stator 3b. The connecting plate 3d3 is supported on the outer circumference of the lower wall portion 3e12 of the drive unit casing 3e1 so as to be slidable in the axial direction X by a slide bush or the like. The linear actuator 3d2 is coupled to the connecting plate 3d3, and when the linear actuator 3d2 is actuated, the connecting plate 3d3 slides on the outer circumference of the lower wall portion 3e12 in the axial direction X. Consequently, the operating pin 3d1 connected to the connecting plate 3d3 moves in the axial direction X, and the stator 3b coupled to the operating pin 3d1 moves in the axial direction X (upward or downward).

[0020] Figures 3A to 3D show the stator 3b. The stator 3b has a stator base 3b1, a first stator peripheral wall 3b2, and a second stator peripheral wall 3b3. The stator base 3b1 has an annular flange portion 3b11 and an inlet portion 3b12 that rises downward from the inner circumference of the flange portion 3b11. The outer circumference of the inlet portion 3b12 is formed as a cylindrical surface centered on axis X, and the inner circumference of the inlet portion 3b12 is formed as a conical surface centered on axis X. The first stator peripheral wall portion 3b2 and the second stator peripheral wall portion 3b3 are each formed as cylindrical shapes centered on axis X and extend downward from the lower end of the inlet portion 3b12. The outer circumference of the first stator peripheral wall portion 3b2 is continuous with the outer circumference of the inlet portion 3b12, and the second stator peripheral wall portion 3b3 is located on the inner side of the first stator peripheral wall portion 3b2 at a predetermined radial distance.

[0021] The first stator circumferential wall portion 3b2 has a stator main region S1 in which a plurality of stator penetration portions 3b21 that penetrate the first stator circumferential wall portion 3b2 are arranged in the circumferential direction, and a stator continuous region 3b22 that extends from the stator main region S1 to the end of the first stator circumferential wall portion 3b2 and is continuous in the circumferential direction. In this embodiment, each stator penetration portion 3b21 takes the form of an elongated hole inclined at a predetermined angle with respect to the axis X when the first stator circumferential wall portion 3b2 is viewed from the outer circumferential side. The second stator circumferential wall portion 3b3 has the same configuration as the first stator circumferential wall portion 3b2, and the stator main region of the second stator circumferential wall portion 3b3 (where a plurality of stator penetration portions 3b31 are arranged in the circumferential direction) faces the stator main region S1 of the first stator circumferential wall portion 3b2 at a predetermined radial distance.

[0022] Here, the "stator main region" is the region between a plane passing through one end of the stator penetration in the axial direction X and perpendicular to the axis X, and a plane passing through the other end of the stator penetration in the axial direction X and perpendicular to the axis X. If the positions of multiple stator penetrations are offset from each other in the axial direction X, the stator main region is defined as the region between the plane passing through one end of the stator penetration located closest to one end in the axial direction X and perpendicular to the axis X, and the plane passing through the other end of the stator penetration located closest to the other end in the axial direction X and perpendicular to the axis X. The same criteria are used to define the stator main region when a large number of stator penetrations, such as circular, elliptical, and polygonal (including triangular and quadrilateral) shapes, are arranged dispersed in the axial direction X and circumferential direction.

[0023] Figures 4A to 4C show the rotor 3c. The rotor 3c has a disc-shaped rotor base 3c1, a rotor peripheral wall 3c2 extending upward from the periphery of the rotor base 3c1, a plurality of block-shaped first stirring blades 3c3 arranged at predetermined distances on the inner circumference side of the rotor peripheral wall 3c2, and a plurality of block-shaped second stirring blades 3c4 arranged at predetermined distances on the inner circumference side of the first stirring blades 3c3. The rotor base 3c1 has a stem portion 3c11 extending downward coaxially with the axis X. The stem portion 3c11 is coupled to the rotation drive shaft 3e2 of the rotation drive unit 3e. The rotor peripheral wall 3c2 is formed in a cylindrical shape centered on the axis X. The first stirring blades 3c3 and the second stirring blades 3c4 are inclined at a predetermined angle with respect to the radius line when the rotor 3c is viewed from above, and are arranged at predetermined intervals along a circle centered on the axis X.

[0024] The rotor circumferential wall portion 3c2 has a rotor main region R1 in which a plurality of rotor penetration portions 3c21 that penetrate the rotor circumferential wall portion 3c2 are arranged in the circumferential direction, and a rotor continuous region R2 that extends from the rotor main region R1 to the end of the rotor circumferential wall portion 3c2 and is continuous in the circumferential direction. In this embodiment, each rotor penetration portion 3c21, when viewed from the outer circumferential side of the rotor circumferential wall portion 3c2, exhibits a rectangular (square or rectangular) or substantially rectangular contour and penetrates the rotor circumferential wall portion 3c2 along a direction inclined at a predetermined angle with respect to the radius. The widths of the rotor main region R1 and the rotor continuous region R2 in the axial X direction are the same as or greater than the width of the stator main region S1 of the first stator circumferential wall portion 3b2 in the axial X direction.

[0025] Here, the "rotor main region" is the region between a plane passing through one end of the rotor penetration in the axial direction X and perpendicular to the axis X, and a plane passing through the other end of the rotor penetration in the axial direction X and perpendicular to the axis X. If the positions of multiple rotor penetrations are offset from each other in the axial direction X, the rotor main region is defined as the region between a plane passing through one end of the rotor penetration located closest to one end in the axial direction X and perpendicular to the axis X, and a plane passing through the other end of the rotor penetration located closest to the other end in the axial direction X and perpendicular to the axis X. The rotor main region is defined using the same criteria when a large number of rotor penetrations, such as circular, elliptical, and polygonal shapes (including triangular and quadrilateral shapes), are arranged dispersed in the axial direction X and circumferential direction.

[0026] As shown in Figure 5, when the stator 3b is in its lowest position (lowest position: Figure 2A) and Figure 6A), the first stator circumferential wall portion 3b2 of the stator 3b is inserted between the rotor circumferential wall portion 3c2 and the first stirring blade 3c3 of the rotor 3, and faces the rotor circumferential wall portion 3c2 and the first stirring blade 3c3, respectively, with a predetermined radial clearance. The second stator circumferential wall portion 3b3 of the stator 3b is inserted between the first stirring blade 3c3 and the second stirring blade 3c4 of the rotor 3, and faces the first stirring blade 3c3 and the second stirring blade 3c4, respectively, with a predetermined radial clearance. The inlet portion 3b12 of the base portion 3b1 of the stator 3b faces the rotor continuous region R2 of the rotor circumferential wall portion 3c2 with a predetermined radial clearance.

[0027] Figures 6A to 6C show the stator 3b in its lowest position (lowest position: corresponding to Figure 6A and Figure 2A), its highest position (highest position: corresponding to Figure 6C and Figure 2B), and its position at an arbitrary location between the lowest and highest positions (intermediate position: Figure 6B). The stator 3b can be moved along the axial direction X by the movement mechanism 3d and set to a desired position selected from the lowest, highest, and intermediate positions.

[0028] At the lowest position of the stator 3b shown in Figure 6A, the entire stator main region S1 of the first stator peripheral wall 3b2 faces the rotor main region R1 of the rotor peripheral wall 3c2 in the radial direction. Furthermore, the entire stator main region S1 of the first stator peripheral wall 3b2 faces the first stirring blade 3c3 in the radial direction, and the entire stator main region of the second stator peripheral wall 3b3 faces the first stirring blade 3c3 and the second stirring blade 3c4 in the radial direction. The inlet portion 3b12 of the base portion 3b1 of the stator 3b faces the rotor continuous region R2 of the rotor peripheral wall 3c2 in the radial direction. When the rotor 3c is driven to rotate, the stirring, suction, and pushing actions associated with the rotation of the first stirring blade 3c3 and the second stirring blade 3c4 draw the material to be processed from the inner circumference of the inlet 3b12 of the stator base 3b1 into the center of the homogenizer 3, and then push it out to the outer circumference of the homogenizer 3. As the material is pushed out to the outer circumference, it sequentially passes through the stator penetration 3b31 of the stator main region of the second stator peripheral wall 3b3, the stator penetration 3b21 of the stator main region S1 of the first stator peripheral wall 3b2, and the rotor penetration 3c21 of the rotor main region R1 of the rotor peripheral wall 3c2, and at that time, it is subjected to shear force by the walls of these main region penetrations. Thus, at the lowest position of the stator 3b, the workpiece being pushed outwards experiences shear force as it passes through the stator penetrations 3b31 across the entire stator main region of the second stator peripheral wall 3b3, the stator penetrations 3b21 across the entire stator main region S1 of the first stator peripheral wall 3b2, and the rotor penetrations 3c21 of the rotor main region R1 of the rotor peripheral wall 3c2. As a result, the shear force acting on the workpiece is maximized. This state is called the "high shear mode." In the high shear mode, no flow of workpiece (short path) occurs, where it passes through the homogenizer 3 without being subjected to the shear action of the stator 3b and rotor 3c.

[0029] At the highest position of the stator 3b shown in Figure 6C, the entire stator main region S1 of the first stator peripheral wall 3b2 is separated upward from the rotor main region R1 of the rotor peripheral wall 3c2 and faces the rotor continuous region R2 of the rotor peripheral wall 3c2 in the radial direction. Also, the entire stator main region S1 of the first stator peripheral wall 3b2 is separated upward from the first stirring blade 3c3, and the entire stator main region of the second stator peripheral wall 3b3 is separated upward from the first stirring blade 3c3 and the second stirring blade 3c4. A portion of the material to be processed, pushed out to the outer circumference by the rotation of the rotor 3c, attempts to flow to the outer circumference by passing through the stator penetration portion 3b21 of the stator main region S1 of the first stator peripheral wall 3b2 (short path), but this flow of material to be processed is blocked by the rotor continuous region R2 which faces the stator main region S1 of the first stator peripheral wall 3b2 in the radial direction. Therefore, the material being pushed outwards flows from the lower end of the second stator peripheral wall 3b3, through the lower end of the first stator peripheral wall 3b2, towards the rotor main region R1 of the rotor peripheral wall 3c2, and through the rotor penetration portion 3c21 of the rotor main region R1 to the outer circumference. In this way, at the highest position of the stator 3b, the material being pushed outwards receives a shear force as it passes through the rotor penetration portion 3c21 of the rotor main region R1 of the rotor peripheral wall 3c2, so the shear force acting on the material is minimized. This state is called the "low shear mode". Even in the low shear mode, there is no flow of material passing through the homogenizer 3 without being subjected to the shear action of the stator 3b and rotor 3c (short path).

[0030] At the intermediate position of the stator 3b shown in Figure 6B, a portion of the stator main region S1 of the first stator peripheral wall 3b2 faces the rotor main region R1 of the rotor peripheral wall 3c2 in the radial direction, while the remaining portion is offset upward from the rotor main region R1 of the rotor peripheral wall 3c2 and faces the rotor continuous region R2 of the rotor peripheral wall 3c2 in the radial direction. Furthermore, the aforementioned portion of the stator main region S1 of the first stator peripheral wall 3b2 faces the first stirring blade 3c3 in the radial direction, and a portion of the stator main region of the second stator peripheral wall 3b3 faces the first stirring blade 3c3 and the second stirring blade 3c4 in the radial direction. A portion of the workpiece pushed outwards by the rotation of the rotor 3c attempts to flow outwards through the stator penetration portion 3b21 in the other area of ​​the stator main region S1 of the first stator peripheral wall portion 3b2 (the portion that is above the rotor main region R1) (short path), but this flow of workpiece is blocked by the rotor continuous region R2 of the first stator peripheral wall portion 3b2 that is radially opposite to the stator main region S1. Therefore, a portion of the material being pushed outwards flows from the stator penetration 3b31 in the aforementioned area of ​​the stator main region of the second stator peripheral wall 3b3 (the portion facing radially from the first stirring blade 3c3 and the second stirring blade 3c4), through the stator penetration 3b21 in the aforementioned area of ​​the stator main region S1 of the first stator peripheral wall 3b2 (the portion facing radially from the rotor main region R1), towards the rotor main region R1 of the rotor peripheral wall 3c2, and then flows outwards through the rotor penetration 3c21 of the rotor main region R1. The remaining portion of the material being pushed outwards flows towards the rotor main region R1 of the rotor peripheral wall 3c2, passing by the lower end of the second stator peripheral wall 3b3 and the lower end of the first stator peripheral wall 3b2, and then flows outwards through the rotor penetration 3c21 of the rotor main region R1. Thus, at the intermediate position of the stator 3b, a portion of the workpiece being pushed outward is subjected to shear force as it passes through the stator penetration portion 3b31 in the aforementioned partial range of the stator main region of the second stator peripheral wall portion 3b3, the stator penetration portion 3b21 in the aforementioned partial range of the stator main region S1 of the first stator peripheral wall portion 3b2, and the rotor penetration portion 3c21 in the rotor main region R1 of the rotor peripheral wall portion 3c2. As a result, the shear force acting on this portion of the workpiece is maximized.On the other hand, the remaining portion of the workpiece being pushed outwards experiences shear force as it passes through the rotor penetration portion 3c21 of the rotor main region R1 of the rotor peripheral wall portion 3c2, so the shear force acting on this remaining portion of the workpiece is minimized. Therefore, considering the entire workpiece being pushed outwards, the shear force acting on the workpiece is intermediate between the maximum and minimum. This state is called the "medium shear mode." Even in the medium shear mode, there is no flow of workpiece that passes through the homogenizer 3 without experiencing shear action from the stator 3b and rotor 3c (short path). In the medium shear mode, the shear force can be freely adjusted by adjusting the axial X position of the stator 3b.

[0031] Referring to Figure 1, the processing of the material to be processed in the agitated tank 1 is carried out by rotating the agitator blade 2 (rotary drive shaft 2a) and the homogenizer 3 (rotor 3c). The rotation speed (rpm) of the agitator blade 2 is set to a lower rotation speed (rpm) than that of the homogenizer 3. The rotation of the agitator blade 2 agitates the material to be processed in the agitated tank 1. At the same time, the feed blade 8, which is provided at the lower end of the rotary drive shaft 2a, rotates at the same rotation speed as the agitator blade 2, so that the material to be processed in the agitated tank 1 is pushed downward by the helical blade portion 8b of the feed blade 8 and pumped towards the homogenizer 3. The material to be processed, which has been pumped downward by the feed blade 8 and has reached the vicinity of the homogenizer 3, is sucked into the center of the homogenizer 3 by the suction action accompanying the rotation of the homogenizer 3 (rotor 3c). The material to be processed, after being mixed, emulsified, dispersed, etc., inside the homogenizer 3, is pushed out of the homogenizer 3 to the outer circumference and enters the circulation pipe 4, and is returned to the inside of the stirring tank 1 via the circulation pipe 4. Thereafter, the same circulation process is repeated the required number of times (number of passes). The processed material, once processed, is pushed out of the homogenizer 3 into the circulation pipe 4 and discharged as processed product (final product, intermediate product, etc.) from the discharge pipe 4b (with the discharge valve 4a open) connected to the circulation pipe 4.

[0032] As described above, the homogenizer 3 of this embodiment can select a desired mode from high shear mode, medium shear mode, and low shear mode by moving the stator 3b in the axial direction X using the moving mechanism 3d. In the intermediate mode, the shear force can be freely adjusted by adjusting the position of the stator 3b in the axial direction X. This makes it possible to select the optimal mode and adjust the shear force to process the material according to the physical properties of the material to be processed (viscosity, ratio of liquid to solid content, particle size of solids, etc.), the target quality of the processed product, and the processing efficiency. Moreover, changes between the above modes can be made during processing without interrupting the processing of the material. For example, the material can be processed in high shear mode or medium shear mode, and the processed product can be discharged in low shear mode. This can increase the discharge efficiency of the processed product and maintain the quality of the processed product at the end of processing. Furthermore, if there are circumstances such as not wanting to cut the structure of polymers in the material to be processed, the processing and discharge of the material can be performed in low shear mode.

[0033] Furthermore, in the homogenizer 3 of this embodiment, in all modes—high shear mode, medium shear mode, and low shear mode—there is no flow of material to be processed that passes through the homogenizer 3 without being subjected to the shear action of the stator 3b and rotor 3c (short path), so the entire material to be processed can be processed uniformly and efficiently.

[0034] In the homogenizer 3 of the embodiment described above, the rotor peripheral wall portion 3c2 is located on the outermost periphery, and the inner circumference of the rotor peripheral wall portion 3c2 and the outer circumference of the first stator peripheral wall portion 3b2 are facing each other with a radial clearance between them. However, the rotor peripheral wall portion may be inserted between the first stator peripheral wall portion and the second stator peripheral wall portion, and the outer circumference of the rotor peripheral wall portion may face the inner circumference of the first stator peripheral wall portion with a radial clearance between them. Furthermore, the first stator peripheral wall portion 3b2 may have a form in which the stator penetration portion 3b2 of the main region S1 penetrates the lower end (a so-called comb-tooth form) (the same applies to the second stator peripheral wall portion 3b3). Moreover, the stator 3b may be configured to omit the second stator peripheral wall portion 3b3 and have only the first stator peripheral wall portion 3b2.

[0035] The homogenizer 3 of the above-described embodiment can be applied not only to batch-type stirring devices as shown in Figure 1, but also to in-line stirring devices (dispersion devices). In this case, the supply line for the material to be processed is connected to the inlet 3b12 of the stator base 3b1, or to the part of the casing 3a facing the inlet 3b12, and the discharge line for the processed product is connected to the side of the casing 3a (the part to which the circulation pipe 4 is connected). [Explanation of symbols]

[0036] 1. Agitation tank 3. Homogenizer 3a Casing 3b stater 3b1 Stator base 3b2 First stator peripheral wall S1 main area 3b21 Stator penetration 3b3 Second stator peripheral wall 3b31 Stator penetration 3c rotor 3c1 Rotor base 3c2 Rotor peripheral wall R1 Rotor main area R2 Rotor continuous region 3c21 Rotor penetration 3d moving mechanism

Claims

1. A homogenizer comprising a casing, a stator and a rotor arranged inside the casing such that their axes are coaxial, and a moving mechanism for relative movement of the stator and the rotor in a direction along the axis, The stator has a stator base and a stator circumferential wall portion extending from the stator base in one direction along the axis, and the stator circumferential wall portion is provided with a stator main region in which a plurality of stator penetration portions that penetrate the stator circumferential wall portion are arranged in the circumferential direction. The rotor has a rotor base and a rotor circumferential wall portion extending from the rotor base in a direction other than that along the axis and facing the stator circumferential wall portion with a predetermined radial clearance, and the rotor circumferential wall portion is provided with a rotor main region in which a plurality of rotor penetration portions that penetrate the rotor circumferential wall portion are arranged in the circumferential direction and a rotor continuous region that is continuous in the circumferential direction from the rotor main region to the end of the rotor circumferential wall portion. A homogenizer that can switch between the following states by the relative movement between the stator and the rotor: a state in which the entire main region of the stator faces the main region of the rotor in the radial direction; a state in which a portion of the main region of the stator faces the main region of the rotor in the radial direction and the rest of the main region of the stator faces the continuous region of the rotor in the radial direction; and a state in which the entire main region of the stator faces the continuous region of the rotor in the radial direction.

2. A stirring device comprising a stirring tank for containing a material to be processed, and a homogenizer according to claim 1 attached to the stirring tank.

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