Kneading device

Abstract

To suppress heat generation of a material in a rotor that can apply high stress to the material.SOLUTION: A first outer peripheral part 50e of a first rotor 50 is provided with a first circular-arc part 51 and a first noncircular-arc part 53. The first circular-arc part 51 extends in the peripheral direction of the first rotor 50 continuously by 1 / 3 or more of the entire peripheral length of a first virtual circle 50c. A second outer peripheral part 60e of a second rotor 60 is provided with a second circular-arc part 61 and a second noncircular-arc part 63. The second circular-arc part 61 extends in the peripheral direction (second peripheral direction) of the second rotor 60 continuously by 1 / 3 or more of the entire peripheral length of a second virtual circle 60c. There is a timing when the first noncircular-arc part 53 and the second circular-arc part 61 face each other (A) between a first rotary shaft 50a and a second rotary shaft 60a.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a kneading device for kneading materials. [Background technology]

[0002] For example, a conventional kneading device is described in Patent Document 1. The kneading device described in this document has a rotor with blades (see the abstract of Patent Document 1, FIG. 2, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4542605 Summary of the Invention [Problem to be solved by the invention]

[0004] When materials are mixed using a working fluid in a supercritical or subcritical state, the viscosity of the materials is reduced compared to mixing at atmospheric pressure. As a result, the stress that the mixer can impart to the materials is reduced, and there is a risk that the materials will not be sufficiently dispersed. On the other hand, when a rotor capable of imparting high stress to the materials is used, heat generation from the materials may become a problem. Therefore, it is desirable to be able to suppress heat generation from the materials in a rotor capable of imparting high stress to the materials.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a kneading device capable of suppressing heat generation from a material in a rotor capable of applying high stress to the material. [Means for solving the problem]

[0006] The kneading device includes a kneading chamber, a first rotor, and a second rotor. The kneading chamber is a portion for kneading materials in the presence of a working fluid in a supercritical state or a subcritical state. The first rotor is disposed inside the kneading chamber and rotates around a first rotation axis. The second rotor is disposed inside the kneading chamber, disposed parallel to the first rotor, disposed adjacent to the first rotor, and rotates around the second rotation axis in a direction opposite to the rotation direction of the first rotor. The first rotor includes a first outer periphery. The first outer periphery is an outer periphery of a cross section of the first rotor as viewed from a direction in which the first rotation axis extends. The first outer periphery includes a first arc portion and a first non-arc portion. The first non-arc portion is a portion of the first outer periphery that is different from the first arc portion. A virtual circle that passes through the first arc portion and is centered on the first rotation axis when viewed from a direction in which the first rotation axis extends is defined as a first virtual circle. The first arc portion is an arc shape centered on the first rotating shaft, is disposed at the radially outermost portion of the first rotor, and extends continuously in the circumferential direction of the first rotor for 1 / 3 or more of the total circumference of the first virtual circle. The second rotor includes a second outer circumferential portion. The second outer circumferential portion is an outer circumferential portion of a cross section of the second rotor as viewed from the direction in which the second rotating shaft extends. The second outer circumferential portion includes a second arc portion and a second non-arc portion. The second non-arc portion is a portion of the second outer circumferential portion different from the second arc portion. A virtual circle that passes through the second arc portion and is centered on the second rotating shaft when viewed from the direction in which the second rotating shaft extends is defined as a second virtual circle. The second arc portion is an arc shape centered on the second rotating shaft, is disposed at the radially outermost portion of the second rotor, and extends continuously in the circumferential direction of the second rotor for 1 / 3 or more of the total circumference of the second virtual circle. There is a timing when the first non-circular portion and the second circular portion face each other between the first rotation shaft and the second rotation shaft. Effect of the Invention

[0007] The above kneading device makes it possible to suppress heat generation from the material in the rotor, which can impart high stress to the material. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view of the kneading device 1 as viewed from an axial direction Z. [Diagram 2] 1. FIG. 2 is a diagram showing the first rotor 50 and the second rotor 60 as viewed from the axial direction Z at a certain moment when the first rotor 50 and the second rotor 60 shown in FIG. 1 are in opposite phases. [Diagram 3] 1. FIG. 2 is a diagram showing the first rotor 50 and the second rotor 60 as viewed from the axial direction Z at a certain moment when the first rotor 50 and the second rotor 60 shown in FIG. 1 are in positive phase. [Figure 4] FIG. 2 is a perspective view showing a rotor 40 and the like shown in FIG. [Diagram 5] 2 is a graph showing the torque of the rotor 40 when the phases of the first rotor 50 and the second rotor 60 shown in FIG. 1 are changed. [Figure 6] 2 is a development view of the first rotor 50 shown in FIG. [Figure 7] 1 is a cross-sectional view of a kneading device 201 according to a second embodiment as viewed from an axial direction Z. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (First embodiment) A kneading device 1 of a first embodiment will be described with reference to Figs. 1 to 6.

[0010] As shown in Fig. 1, the kneading device 1 (kneading machine) is a device that kneads materials using a working fluid in a supercritical state or a subcritical state. Hereinafter, "supercritical state or subcritical state" is also referred to as "supercritical state, etc." The kneading device 1 is, for example, a batch type. In the kneading device 1, the working fluid in a supercritical state, etc., swells in the material, melts the material (plasticizes it), and kneads the material in a state in which the viscosity of the material is reduced.

[0011] The materials kneaded by this kneading device 1 include, for example, a main material and an auxiliary material. The main material includes, for example, a polymer material, and specifically includes, for example, rubber (such as tire rubber) or resin. The auxiliary material is an additive (compounding agent) added (compounded) to the main material. The auxiliary material may contain inorganic substances or organic substances. Specifically, for example, when the main material is rubber, the auxiliary material is silica, a coupling agent, a vulcanizing agent, etc.

[0012] The working fluid used in this kneading device 1 is a fluid in a supercritical state (supercritical fluid) or a fluid in a subcritical state (subcritical fluid). The kneading device 1 is a supercritical kneading device or a subcritical kneading device. The temperature of the supercritical fluid is equal to or higher than the critical temperature (Tc), and the pressure of the supercritical fluid is equal to or higher than the critical pressure (Pc). The supercritical fluid has the characteristics of both a liquid and a gas. The supercritical fluid has the ability to dissolve solutes (solubility) similar to that of a liquid and the ability to diffuse solutes (diffusibility) similar to that of a gas. The characteristics (solubility and diffusibility) of the subcritical fluid are almost the same as those of the supercritical fluid. The temperature (T) and pressure (P) of the subcritical fluid satisfy, for example, any of the following conditions. The units of temperature (T) and critical temperature (Tc) in each of the following examples are in degrees Celsius. [Example 1 of subcritical state] Satisfies T≥Tc and P<Pc. [Example 2 of subcritical state] Satisfies T<Tc, P<Pc, T is sufficiently higher than room temperature, and P is sufficiently higher than normal pressure (atmospheric pressure). [Example 3 of subcritical state] Satisfies 0.5<T / Tc<1.0 and 0.5<P / Pc. [Example 4 of subcritical state] Satisfies 0.5<T / Tc and 0.5<P / Pc<1.0. [Example 5 of subcritical state] When the critical temperature (Tc) is 0°C or lower, satisfies 0.5<P / Pc.

[0013] The substance constituting the working fluid is preferably a substance that can be put into a supercritical state or a subcritical state as easily as possible. The difference between the polarity of the working fluid and the polarity of the material is small enough that the material can be dissolved in the working fluid. The substance constituting the working fluid is, for example, carbon dioxide. The critical temperature (Tc) of carbon dioxide is 31°C. The critical pressure (Pc) of carbon dioxide is 7.4 MPa. Carbon dioxide is in a subcritical state, for example, when it is 31°C or higher and 7.1 MPa or higher. Carbon dioxide is in a subcritical state, for example, when it is 15 MPa or higher at 20°C. Note that the substance constituting the working fluid does not have to be carbon dioxide, and may be, for example, nitrogen. It is preferable that the working fluid is in a supercritical state rather than a subcritical state. When the working fluid is in a supercritical state, the material is kneaded more than when the working fluid is in a subcritical state.

[0014] The kneading device 1 includes a chamber 10 and a rotor 40 .

[0015] (Direction relative to the kneading device 1) The directions related to the kneading device 1 include a lateral direction X, a vertical direction Y, and an axial direction Z. The axial direction Z is the direction in which the first rotation shaft 50a and the second rotation shaft 60a described later extend. The lateral direction X is a direction perpendicular to the axial direction Z, and is the direction in which a straight line passing through the first rotation shaft 50a and the second rotation shaft 60a extends when viewed from the axial direction Z. The lateral direction X may be a horizontal direction, and does not have to be a horizontal direction unless otherwise specified. In the lateral direction X, the side (direction) from the second rotation shaft 60a toward the first rotation shaft 50a is the lateral first side X1, and the side opposite to the lateral first side X1 is the lateral second side X2. The vertical direction Y is a direction perpendicular to each of the axial direction Z and the lateral direction X. The vertical direction Y may be a vertical direction, and does not have to be a vertical direction unless otherwise specified. One side in the vertical direction Y is the lower side Y2. As described later, the first rotor 50 and the second rotor 60 rotate in opposite directions, and the direction of movement of the second lateral side X2 of the first rotor 50 and the first lateral side X1 of the second rotor 60 is referred to as the lower side Y2. In the vertical direction Y, the opposite side to the lower side Y2 is referred to as the upper side Y1. The upper side Y1 may be on the vertical direction, and does not have to be on the vertical direction unless otherwise specified. The radial direction of a first imaginary circle 50c centered on the first rotating shaft 50a, which will be described later, is referred to as the first radial direction. The circumferential direction of the first imaginary circle 50c is referred to as the first circumferential direction. The radial direction of a second imaginary circle 60c centered on the second rotating shaft 60a, which will be described later, is referred to as the second radial direction. The circumferential direction of the second imaginary circle 60c is referred to as the second circumferential direction.

[0016] The chamber 10 is a container for kneading materials. The chamber 10 includes a kneading chamber 10a.

[0017] The kneading chamber 10a is a portion where the material is kneaded. The kneading chamber 10a is a portion where the material is kneaded in the presence (atmosphere) of a working fluid such as a supercritical state. The kneading chamber 10a is disposed inside the chamber 10. The kneading chamber 10a includes a space (kneading space) where the material is kneaded, and an inner surface of the chamber 10 that forms (surrounds) the kneading space. The kneading chamber 10a is sealed so that the working fluid inside the kneading chamber 10a can maintain a state such as a supercritical state. The kneading chamber 10a includes a rotor accommodating chamber 20 and a rotor shaft upper chamber 30.

[0018] The rotor accommodating chamber 20 is a portion that accommodates the rotor 40. The rotor accommodating chamber 20 includes a space that accommodates the rotor 40 (rotor accommodating space) and an inner surface of the chamber 10 that forms the rotor accommodating space. When two rotors 40 are provided, the rotor accommodating chamber 20 includes a first rotor accommodating chamber 21 and a second rotor accommodating chamber 22.

[0019] The first rotor accommodating chamber 21 accommodates the first rotor 50. The first rotor accommodating chamber 21 has an inner circumferential surface centered on a first rotating shaft 50a (described later). When viewed from the axial direction Z, the inner circumferential surface of the first rotor accommodating chamber 21 is in the shape of a circular arc centered on the first rotating shaft 50a.

[0020] The second rotor accommodating chamber 22 is a portion that accommodates the second rotor 60. The second rotor accommodating chamber 22 has an inner circumferential surface centered on a second rotation shaft 60a (described later). When viewed from the axial direction Z, the inner circumferential surface of the second rotor accommodating chamber 22 is in the shape of a circular arc centered on the second rotation shaft 60a. The space of the first rotor accommodating chamber 21 and the space of the second rotor accommodating chamber 22 (i.e., the rotor accommodating space of the rotor accommodating chamber 20) are substantially shaped like glasses when viewed from the axial direction Z.

[0021] The rotor-shaft upper chamber 30 increases the amount of material that can be put into the kneading chamber 10a (e.g., the production amount by the kneading device 1). The rotor-shaft upper chamber 30 extends from the first rotor accommodating chamber 21 and the second rotor accommodating chamber 22 to the upper side Y1 (here, upward in the vertical direction). The rotor-shaft upper chamber 30 is disposed in the rotor-shaft area A. The rotor-shaft area A is an area between the first rotating shaft 50a and the second rotating shaft 60a in the lateral direction X. The rotor-shaft area A is an area on the second lateral side X2 of the first rotating shaft 50a and on the first lateral side X1 of the second rotating shaft 60a. At least a part of the rotor-shaft upper chamber 30 is disposed in the rotor-shaft area A. A part of the rotor-shaft upper chamber 30 may be disposed on the outer side in the lateral direction X of the rotor-shaft area A.

[0022] The shape of the rotor-shaft upper chamber 30 can be set in various ways (arbitrarily). In the example shown in FIG. 1, the inner surface (referred to as the "left side surface") of the first lateral side X1 of the rotor-shaft upper chamber 30 extends from the upper Y1 portion (e.g., the upper Y1 end portion) of the first rotor accommodating chamber 21 to the upper side Y1. The left side surface of the rotor-shaft upper chamber 30 extends to the upper side Y1 from a position directly above the first rotating shaft 50a in the first rotor accommodating chamber 21. The left side surface of the rotor-shaft upper chamber 30 extends in a direction inclined with respect to the vertical direction Y so that the left side surface is disposed on the second lateral side X2 toward the upper side Y1. The left side surface of the rotor-shaft upper chamber 30 may extend in a direction that coincides with the vertical direction Y. The inner surface (right side surface) of the second lateral side X2 of the rotor-shaft upper chamber 30 may be provided symmetrically (e.g., bilaterally symmetrically) in the horizontal direction X with the left side surface of the rotor-shaft upper chamber 30, or may not be provided symmetrically.

[0023] The rotor 40 kneads the material by rotating relative to the kneading chamber 10a. The rotor 40 is disposed (housed) inside the kneading chamber 10a, and disposed (housed) in the rotor housing chamber 20. A plurality of rotors 40 are provided, for example, two rotors 40 are provided, and three or more rotors 40 may be provided. Among the plurality of rotors 40, two adjacent rotors 40 are referred to as a first rotor 50 and a second rotor 60.

[0024] The first rotor 50 is one of the rotors 40. The first rotor 50 rotates around a first rotation shaft 50a. The first rotor 50 is arranged (housed) inside the kneading chamber 10a, and arranged (housed) inside the first rotor housing chamber 21. As shown in FIG. 4, the first rotor 50 is provided so as to extend in the direction in which the first rotation shaft 50a extends (axial direction Z). In FIG. 4, the chamber 10 is shown by an imaginary line (two-dot chain line). As shown in FIG. 1, the first rotation shaft 50a is the rotation shaft of the first rotor 50 relative to the kneading chamber 10a (relative to the chamber 10). When viewed from the axial direction Z, a virtual circle passing through a first arc portion 51 described later and centered on the first rotation shaft 50a is defined as a first virtual circle 50c. The first virtual circle 50c is a virtual circle perpendicular to the axial direction Z. The first rotor 50 has a first outer circumferential portion 50e. When the first outer circumferential portion 50e includes a first protruding portion 53a described below, the first rotor 50 includes a first base portion 55 (see FIG. 2).

[0025] 2, the first outer peripheral portion 50e is an outer peripheral portion of a cross section of the first rotor 50 as viewed from the axial direction Z. The first outer peripheral portion 50e is a peripheral portion on a first radially outer side of the cross section of the first rotor 50 as viewed from the axial direction Z. The first outer peripheral portion 50e includes a first arc portion 51 and a first non-arcuate portion 53.

[0026] The first arc portion 51 has an arc shape centered on the first rotating shaft 50a when viewed from the axial direction Z. The first arc portion 51 is a portion (maximum outer diameter portion) of the first rotor 50 that is disposed at the outermost portion in the first radial direction. The first arc portion 51 has a function of applying high stress to the material (described later). The first arc portion 51 is disposed along the first imaginary circle 50c. The first arc portion 51 extends in the first circumferential direction continuously for at least ⅓ of the entire circumferential length of the first imaginary circle 50c (the length of the first arc portion 51 will be described later in detail).

[0027] The first non-arc portion 53 is a portion of the first outer peripheral portion 50e that is different from the first arc portion 51 (a portion other than the first arc portion 51). The portion of the first outer peripheral portion 50e that is not the first arc portion 51 is the first non-arc portion 53. The first non-arc portion 53 has a function of suppressing heat generation of the material (described later). The first non-arc portion 53 can have various shapes (structures). The first non-arc portion 53 may have only a concave shape (see, for example, the first recess 253b shown in FIG. 7). The first non-arc portion 53 may have an uneven shape as in the example shown in FIG. 2. The first non-arc portion 53 may have a wing shape (see, for example, the first convex portion 53a). For example, the first non-arc portion 53 includes a first convex portion 53a, a first recess 53b, and a first twisted portion 53c (see FIG. 4).

[0028] The first convex portion 53a is a portion (projection portion, wing portion) that protrudes from the first base portion 55 to the outside in the first radial direction. Only one first convex portion 53a may be provided, or multiple first convex portions 53a may be provided. In the example shown in FIG. 2, two first convex portions 53a are provided, and three or more first convex portions 53a may be provided. The first rotor 50 is a hybrid rotor having both a substantially cylindrical (substantially roll-shaped) first base portion 55 and a wing-shaped first convex portion 53a. When multiple first convex portions 53a are provided, the configurations of the multiple first convex portions 53a may be the same as each other, may be substantially the same as each other, or may be different. In the example shown in FIG. 2, the configurations of the two first convex portions 53a are symmetrical to each other in the first circumferential direction. The width of the first convex portion 53a in the first circumferential direction may be narrower toward the outside in the first radial direction (may be tapered), or may be constant.

[0029] The first recess 53b is a portion for distributing the material more (reducing the unevenness of the material and reducing uneven mixing). The first recess 53b is a portion for taking in the material in the rotor gap upper portion Ay1 (see FIG. 1) and moving the material to the rotor gap lower portion Ay2 (see FIG. 1). The first recess 53b has a shape recessed toward the first radially inner side (the inner side in the radial direction of the first rotor 50). The first recess 53b is disposed on the first radially inner side of the first virtual circle 50c. The above-mentioned "recessed shape" of the first recess 53b is, for example, a groove shape (see FIG. 4). The first recess 53b may include a straight line or a curved line when viewed from the axial direction Z, and may include, for example, an arc shape (a circular arc shape or a non-circular arc shape). For example, the first recess 53b includes a first inter-protrusion recess 53b1 and a first inter-protrusion outer recess 53b2.

[0030] The first inter-convex recess 53b1 is formed by two first convex portions 53a adjacent to each other in the first circumferential direction. When the first rotor 50 has two first convex portions 53a, the region between the two first convex portions 53a includes a region that is shorter in the first circumferential direction and a region that is longer in the first circumferential direction. In this case, the first inter-convex recess 53b1 is formed (disposed) in the region between the two first convex portions 53a that is shorter in the first circumferential direction.

[0031] The first inter-convex-portion outer recess 53b2 is disposed on the "first inter-convex-portion outer side" of the first convex portion 53a. The "first inter-convex-portion outer side" is the opposite side of the first convex portion 53a from the first inter-convex-portion recess 53b1 (opposite side in the first circumferential direction). The first inter-convex-portion outer recess 53b2 is formed by the first convex portion 53a. In the example shown in FIG. 2, the first inter-convex-portion outer recess 53b2 is disposed in the region between the first convex portion 53a and the first arc portion 51. The first inter-convex-portion outer recess 53b2 is provided on the first inter-convex-portion outer side of each of the two first convex portions 53a (two in total).

[0032] The first twisted portion 53c (see FIG. 4) is a portion for distributing the material in the axial direction Z. The first twisted portion 53c is a portion for inducing a flow of the material in the axial direction Z and promoting the distribution of the material in the axial direction Z. As shown in FIG. 4, the first twisted portion 53c has a shape twisted about the first rotation axis 50a so as to extend in a direction inclined with respect to the first rotation axis 50a. The first twisted portion 53c has a shape twisted in a "predetermined twist direction" about the first rotation axis 50a. That is, the cross-sectional shape of the first twisted portion 53c as viewed from the axial direction Z is a shape that rotates in a "predetermined twist direction" as the position in the axial direction Z changes. The above-mentioned "predetermined twist direction" is a clockwise or counterclockwise direction when viewed from one side in the axial direction Z. Specifically, the first convex portion 53a and the first concave portion 53b are spiral-shaped with the first rotation axis 50a as the central axis. The first twisted portion 53c is provided over the entirety (or substantially the entirety) of the first rotor 50 in the axial direction Z. Note that the first twisted portion 53c may be provided over only a portion of the first rotor 50 in the axial direction Z.

[0033] 2, the first base portion 55 is a portion of the first rotor 50 other than the first protruding portion 53a. The first base portion 55 includes, for example, the first rotating shaft 50a.

[0034] As shown in FIG. 1, the second rotor 60 is one of the rotors 40 and is provided separately from the first rotor 50. The second rotor 60 rotates about a second rotation shaft 60a. The second rotation shaft 60a is the rotation shaft of the second rotor 60 relative to the kneading chamber 10a (relative to the chamber 10). When viewed from the axial direction Z, a virtual circle passing through a second arc portion 61 described later and centered on the second rotation shaft 60a is defined as a second virtual circle 60c. The second virtual circle 60c is a virtual circle perpendicular to the axial direction Z.

[0035] The second rotor 60 rotates in a direction opposite to the rotation direction of the first rotor 50. Specifically, for example, when viewed from one side in the axial direction Z, when the first rotor 50 rotates clockwise, the second rotor 60 rotates counterclockwise. The magnitude (number of rotations) of the rotation speed of the second rotor 60 is equal to or approximately equal to the magnitude of the rotation speed of the first rotor 50. Note that the magnitude of the rotation speed of the second rotor 60 may be different from the magnitude of the rotation speed of the first rotor 50.

[0036] The second rotor 60 is disposed (housed) inside the kneading chamber 10a, and disposed (housed) inside the second rotor housing chamber 22. As shown in FIG. 4, the second rotor 60 is disposed parallel to the first rotor 50. Specifically, the extension direction of the first rotation shaft 50a and the extension direction of the second rotation shaft 60a are parallel to each other. As shown in FIG. 1, the second rotor 60 is disposed so as to be adjacent to the first rotor 50. The second rotor 60 is disposed so that a small gap is formed in the lateral direction X between the first imaginary circle 50c and the second imaginary circle 60c.

[0037] The configuration (structure, shape, etc.) of the second rotor 60 is, for example, the same as the configuration of the first rotor 50. The configuration of the second rotor 60 may be different from the configuration of the first rotor 50. The configuration of the second rotor 60 may be substantially the same as the configuration of the first rotor 50, or may be completely different from the configuration of the first rotor 50. Below, a case where the configuration of the first rotor 50 and the configuration of the second rotor 60 are the same will be described. As shown in FIG. 2, the second rotor 60 has a second outer circumferential portion 60e. When the second outer circumferential portion 60e has a second convex portion 63a, the second rotor 60 has a second base portion 65.

[0038] The second outer circumferential portion 60e (corresponding to the first outer circumferential portion 50e of the first rotor 50) is an outer circumferential portion of a cross section of the second rotor 60 as viewed from the axial direction Z. The second outer circumferential portion 60e includes a second arc portion 61 and a second non-arcuate portion 63.

[0039] The second arc portion 61 (corresponding to the first arc portion 51) is an arc shape centered on the second rotating shaft 60a when viewed from the axial direction Z. The second arc portion 61 is a portion (maximum outer diameter portion) of the second rotor 60 that is disposed at the outermost portion in the second radial direction. The second arc portion 61 is disposed along the second imaginary circle 60c. The second arc portion 61 extends in the second circumferential direction continuously for ⅓ or more of the entire circumference of the second imaginary circle 60c (details will be described later). As shown in FIG. 1, there is a timing when the first non-arc portion 53 and the second arc portion 61 face each other between the first rotating shaft 50a and the second rotating shaft 60a (rotor shaft region A) (details will be described later).

[0040] As shown in FIG. 2, the second non-arc portion 63 (corresponding to the first non-arc portion 53) is a portion of the second outer circumferential portion 60e that is different from the second arc portion 61 (a portion other than the second arc portion 61). For example, the second non-arc portion 63 includes a second convex portion 63a, a second concave portion 63b, and a second twist portion 63c (see FIG. 4) (corresponding to the first twist portion 53c). The second convex portion 63a (corresponding to the first convex portion 53a) is a portion (projection portion, wing portion) that protrudes from the second base portion 65 to the outside in the second radial direction. The second concave portion 63b (corresponding to the first concave portion 53b) has a shape that is concave toward the inside in the second radial direction, and is disposed on the inside in the second radial direction of the second imaginary circle 60c.

[0041] As shown in Fig. 4, the second twisted portion 63c has a shape twisted in a "predetermined twisted direction" around the second rotating shaft 60a. This "predetermined twisted direction" is the same direction as the twisted direction ("predetermined twisted direction") of the first twisted portion 53c. The second twisted portion 63c is provided over the entire (or substantially the entire) axial direction Z of the second rotor 60. Note that the second twisted portion 63c may be provided only in a part of the axial direction Z of the second twisted portion 63c.

[0042] (Action of twisted part) The first twisted portion 53c and the second twisted portion 63c distribute the material in the axial direction Z. More specifically, as described above, the first rotor 50 and the second rotor 60 rotate in opposite directions. The first twisted portion 53c and the second twisted portion 63c have the same twist direction. Therefore, the direction of movement of the material in the axial direction Z accompanying the rotation of the first rotor 50 and the direction of movement of the material in the axial direction Z accompanying the rotation of the second rotor 60 are opposite to each other. Therefore, the first twisted portion 53c and the second twisted portion 63c facilitate the distribution of the material in the axial direction Z (the distribution performance in the axial direction Z of the kneading device 1 is improved).

[0043] In addition, when the first twisted portion 53c and the second twisted portion 63c have opposite twist directions, the direction of movement of the material in the axial direction Z accompanying the rotation of the first rotor 50 and the direction of movement of the material in the axial direction Z accompanying the rotation of the second rotor 60 become the same. Then, the material may be biased to one side in the axial direction Z, and the distribution in the axial direction Z may be insufficient. Here, a seal for sealing the kneading chamber 10a is usually provided at the end of the rotor 40 in the axial direction Z in the kneading chamber 10a. If the material is biased to one side in the axial direction Z, the material may push this seal with a large force and affect the seal. Therefore, it is preferable that the twisted direction is the same (predetermined twisted direction) in the first twisted portion 53c and the second twisted portion 63c.

[0044] A second base portion 65 (see FIG. 2) (corresponding to the first base portion 55) is a portion of the second rotor 60 other than the second protruding portion 63a.

[0045] (Activation) The kneading device 1 shown in FIG. 1 is configured to operate as follows. The material and working fluid are placed in a sealed kneading chamber 10a. In this state, the rotor 40 rotates relative to the kneading chamber 10a. The material moves from the rotor gap upper part Ay1 to the rotor gap lower part Ay2, passes through the gap between the inner surface of the rotor housing chamber 20 and the rotor 40, and returns to the rotor gap upper part Ay1. As the rotor 40 continues to rotate, the material repeats this movement. As a result, the material is distributed (distributed and mixed, and distribution progresses), and the uneven distribution of the material (uneven mixing) is reduced. Specifically, the uneven distribution of the secondary material in the main material is reduced. In addition, the material is dispersed and finely scattered. Specifically, the secondary material of the material is finely scattered in the main material.

[0046] (Effects caused by the use of working fluids in a supercritical state, etc.) Here, a closed mixer that does not use a working fluid in a supercritical state or the like is referred to as a "conventional closed mixer." When a working fluid in a supercritical state or the like is used, materials can be mixed at low temperatures compared to conventional closed mixers, and heat generation from the materials can be suppressed. Furthermore, when a working fluid in a supercritical state or the like is used, the viscosity of the materials is reduced and the fluidity of the materials is improved compared to conventional closed mixers, so the materials are more distributed. Furthermore, the viscosity of the materials is reduced and the fluidity of the materials is improved, so the power required to mix the materials in the kneading device 1 is reduced.

[0047] (Action of the arc section) When a working fluid such as a supercritical fluid is used, the fluidity of the material is improved compared to conventional internal mixers, but the stress applied to the material is reduced. Therefore, in materials that require physical force to disperse (such as highly cohesive fillers), dispersion may not proceed smoothly (dispersibility may decrease).

[0048] Therefore, the first rotor 50 includes a first arc portion 51, and the second rotor 60 includes a second arc portion 61. The first arc portion 51 and the second arc portion 61 can impart high stress to the material. In detail, the material in the rotor gap upper portion Ay1 passes through the gap between the first rotor 50 and the second rotor 60. As shown in FIG. 3, the gap between the first arc portion 51 and the second arc portion 61 when the first arc portion 51 and the second arc portion 61 face each other is defined as the arc portion gap A1. When the material passes through the arc portion gap A1, an elongation flow in the vertical direction Y occurs in the material, and an elongation stress is imparted to the material (high stress acts on the material). As a result, the dispersibility of the material is improved.

[0049] (Action of non-circular arcs) When the material is kneaded by the first arc portion 51 and the second arc portion 61, high stress can be applied to the material, but heat generation from the material during kneading can become a problem. For example, when the heat generated by the material causes too much (or not enough) chemical reaction of the material, the heat generation from the material can become a problem. Specifically, for example, there is a process (kneading process B) in which a crosslinking agent (secondary material) such as sulfur or a vulcanization accelerator is kneaded with a rubber material (main material). In this kneading process B, if the material generates too much heat during kneading, scorching (excessive vulcanization) occurs in the material, in which crosslinking progresses during kneading, and the material properties may deteriorate.

[0050] To suppress the heat generation of this material, rearrangement of the rotor 40 requires time and effort and costs. Specifically, rearrangement of a rotor (a rotor that generates a lot of heat) when kneading a material that requires physical force for dispersion with a rotor (a rotor that generates little heat) when kneading a material for which heat generation is a problem requires time and effort and costs.

[0051] (Opposing between the first non-circular portion 53 and the second circular portion 61) Therefore, the kneading device 1 is configured to apply high stress to the material and suppress heat generation of the material (allowing kneading at low temperature). Specifically, in the kneading device 1, as shown in FIG. 1, there is a timing when the first non-circular arc portion 53 and the second arc portion 61 face each other (more specifically, face each other in the lateral direction X) between the first rotating shaft 50a and the second rotating shaft 60a (rotor shaft region A). Hereinafter, when an element of the first rotor 50 (here, the first non-circular arc portion 53) and an element of the second rotor 60 (here, the second arc portion 61) "face each other," it means that they face each other in the lateral direction X in the rotor shaft region A. When the first non-circular arc portion 53 and the second arc portion 61 face each other, the range (vertical range) of the second arc portion 61 in the vertical direction Y is included in at least a part of the vertical range of the first non-circular arc portion 53.

[0052] Furthermore, in the kneading device 1, there is a timing (not shown) when the first arc-shaped portion 51 and the second non-arc portion 63 face each other in the rotor shaft region A. When the first arc-shaped portion 51 and the second non-arc-shaped portion 63 face each other, the range (vertical range) of the first arc-shaped portion 51 in the vertical direction Y is included in at least a part of the vertical range of the second non-arc-shaped portion 63. Hereinafter, unless otherwise specified, a description of the first rotor 50 may be read as a description of the second rotor 60, and a description of the second rotor 60 may be read as a description of the first rotor 50.

[0053] When the first non-arcuate portion 53 and the second arcuate portion 61 face each other, the material passes through the arcuate portion-non-arcuate portion gap A3. The arcuate portion-non-arcuate portion gap A3 is the gap between the first non-arcuate portion 53 and the second arcuate portion 61 when the first non-arcuate portion 53 and the second arcuate portion 61 face each other. This arcuate portion-non-arcuate portion gap A3 is larger than the arcuate portion gap A1 (see FIG. 3). Therefore, the amount of heat generated by the material when it passes through the arcuate portion-non-arcuate portion gap A3 is smaller than the amount of heat generated by the material when it passes through the arcuate portion gap A1.

[0054] Note that there may be a timing when the first non-arc portion 53 and the second arc portion 61 do not face each other. For example, the first non-arc portion 53 and the second arc portion 61 may face each other at a certain timing and not face each other at another timing. The first non-arc portion 53 and the second arc portion 61 may face each other periodically. For example, there may be a timing when the first non-arc portion 53 and the second arc portion 61 face each other while at least one of the first rotor 50 and the second rotor 60 rotates once.

[0055] Furthermore, the first non-circular portion 53 and the second arcuate portion 61 do not necessarily have to face each other at another position in the axial direction Z when they face each other at a certain position in the axial direction Z.

[0056] (Relationship between the effect of applying high stress and the effect of suppressing heat generation) The time during which the first arc-shaped portion 51 and the second arc-shaped portion 61 face each other as shown in Fig. 3 is compared with the time during which the first non-arc-shaped portion 53 and the second arc-shaped portion 61 face each other as shown in Fig. 2. As a result, the longer the time during which the first non-arc-shaped portion 53 and the second arc-shaped portion 61 face each other, the greater the effect of suppressing the amount of heat generated by the material (heat generation suppression effect). On the other hand, as shown in Fig. 3, the longer the time during which the first arc-shaped portion 51 and the second arc-shaped portion 61 face each other, the greater the effect of applying high stress to the material (high stress application effect).

[0057] As shown in Fig. 4, there is a case where the first rotor 50 has a first twisted portion 53c, and the second rotor 60 has a second twisted portion 63c. In this case, as shown in Fig. 2, the more the portions where the first non-circular portion 53 and the second arc portion 61 face each other in the axial direction Z, the more the heat generation suppression effect is obtained. Also, as shown in Fig. 3, the more the portions where the first arc portion 51 and the second arc portion 61 face each other in the axial direction Z, the more the high stress application effect is obtained.

[0058] (Difference in effect due to phase) The balance between the effect of applying high stress and the effect of suppressing heat generation (low-temperature kneading) changes depending on the difference in phase between the first rotor 50 and the second rotor 60. For example, as shown in FIG. 3, a phase in which the first arc portion 51 and the second arc portion 61 face each other directly, and the first non-arc portion 53 and the second non-arc portion 63 face each other directly (not shown) is defined as a "positive phase". As shown in FIG. 2, a phase in which the first non-arc portion 53 and the second arc portion 61 face each other directly, and the first arc portion 51 and the second non-arc portion 63 face each other directly (not shown) is defined as an "negative phase". When the positive phase and the negative phase are defined in this way, the closer the first rotor 50 and the second rotor 60 are to the positive phase (see FIG. 3), the greater the effect of applying high stress, and the closer they are to the negative phase (see FIG. 2), the greater the effect of suppressing heat generation.

[0059] (Adjusting the effect by adjusting the phase) When kneading materials or processes that require high stress, it is preferable that the first rotor 50 and the second rotor 60 are in a positive phase or a phase close to the positive phase, as shown in Fig. 3. When kneading materials or processes that do not require high stress, it is preferable that the first rotor 50 and the second rotor 60 are in an opposite phase or a phase close to the opposite phase, as shown in Fig. 2. By adjusting the phase in this way, it is possible to achieve both the effect of applying high stress in the positive phase (see Fig. 3) and the effect of suppressing heat generation in the opposite phase (see Fig. 2) without rearranging the rotor 40.

[0060] (Example of difference in effect due to phase) FIG. 5 shows the average torque and maximum torque of the rotor 40 during kneading when the first rotor 50 and the second rotor 60 are in the positive phase (see FIG. 3) and in the negative phase (see FIG. 2). In this specific example, the first rotor 50 and the second rotor 60 have the same rotation speed and opposite rotation directions. In this specific example, as shown in FIG. 2, the cross-sectional shape of the first rotor 50 and the cross-sectional shape of the second rotor 60 are the same when viewed from the axial direction Z. In this specific example, the length of the first circular arc portion 51 in the first circumferential direction is 1 / 2 the circumference of the first virtual circle 50c, and the length of the first non-circular arc portion 53 in the first circumferential direction is 1 / 2 the circumference of the first virtual circle 50c.

[0061] In the results shown in FIG. 5, when the first rotor 50 and the second rotor 60 are in the opposite phase (see FIG. 2), the average torque is reduced by about 6% and the maximum torque is reduced by about 40% compared to the case of the positive phase (see FIG. 3). Here, a small torque of the rotor 40 (see FIG. 2) indicates that the heat generation of the material is small. Therefore, it can be seen that when the first rotor 50 and the second rotor 60 are in the opposite phase (see FIG. 2), the heat generation of the material during kneading is suppressed by the arc portion and the non-arc portion facing each other (the first arc portion 51 and the second non-arc portion 63 facing each other, and the second arc portion 61 and the first non-arc portion 53 facing each other). Also, a large torque of the rotor 40 (see FIG. 3) indicates that the stress applied to the material is high. Therefore, it can be seen that when the first rotor 50 and the second rotor 60 are in the opposite phase (see FIG. 3), the arc portions facing each other (the first arc portion 51 and the second arc portion 61 facing each other) can apply high stress to the material during kneading.

[0062] (Difference in effect due to rotor 40 shape) The balance between the effect of applying high stress and the effect of suppressing heat generation (low-temperature kneading) changes depending on the length in the first circumferential direction of the first arc-shaped portion 51 relative to the length of the entire circumference of the first virtual circle 50c shown in Fig. 2. Also, the balance between the effect of applying high stress and the effect of suppressing heat generation (low-temperature kneading) changes depending on the length in the first circumferential direction of the second arc-shaped portion 61 relative to the length of the entire circumference of the second virtual circle 60c. Here, the description will be mainly focused on the first rotor 50.

[0063] As described above, the longer the time that the first non-circular arc portion 53 and the second arc portion 61 face each other relative to the time that the first arc portion 51 and the second arc portion 61 face each other, the greater the effect of heat generation suppression. Therefore, by reducing the first arc portion 51 that generates a lot of heat and increasing the first non-circular arc portion 53 in the first outer peripheral portion 50e, the time that the first non-circular arc portion 53 and the second arc portion 61 face each other becomes longer, and the effect of heat generation suppression can be increased. However, if the first arc portion 51 that generates a lot of heat is reduced too much, the effect of high stress application becomes limited. In addition, if the first arc portion 51 that generates a lot of heat is increased too much, heat generation during kneading becomes a problem. Therefore, in the first rotor 50, by adjusting (setting) the length of the first arc portion 51 in the first circumferential direction relative to the length of the entire circumference of the first virtual circle 50c to an appropriate length, the effect of high stress application and the effect of heat generation suppression can be achieved at the same time.

[0064] (Condition for the length of the arc) [Condition α1] The first arc portion 51 extends continuously in the first circumferential direction (circumferential direction of the first rotor 50) for at least 1 / 3 or more of the total circumference of the first virtual circle 50c. In this case, the effect of applying high stress by the first arc portion 51 can be ensured. Note that, even if a portion of the first outer peripheral portion 50e extends along the first virtual circle 50c, a portion whose length in the first circumferential direction is not continuous for 1 / 3 or more of the total circumference of the first virtual circle 50c is not included in the first arc portion 51. For example, in the example shown in FIG. 2, the tip portion of the first convex portion 53a is a portion that extends along the first virtual circle 50c. However, the length in the first circumferential direction of the tip portion of the first convex portion 53a is not continuous for 1 / 3 or more of the total circumference of the first virtual circle 50c. Therefore, the tip portion of the first convex portion 53a is not included in the first arc portion 51.

[0065] The first rotor 50 is provided to extend in the axial direction Z (see FIG. 4), and the above-mentioned [Condition α1] is satisfied at least in some axial direction Z positions (positions in the axial direction Z) of the first rotor 50. The above-mentioned [Condition α1] may be satisfied in some axial direction Z of the first rotor 50. It is preferable that the above-mentioned [Condition α1] is satisfied over the entire axial direction Z of the first rotor 50.

[0066] The second arc-shaped portion 61 of the second rotor 60 satisfies the same condition as the above-mentioned [Condition α1]. That is, the second arc-shaped portion 61 extends continuously in the first circumferential direction for at least ⅓ or more of the entire circumferential length of the second imaginary circle 60c.

[0067] [Condition α2] The length of the first arc-shaped portion 51 that extends continuously in the first circumferential direction is preferably 3 / 4 or less of the total circumference of the first imaginary circle 50c. In this case, the length of the first non-arc portion 53 in the first circumferential direction is longer than 1 / 3 of the total circumference of the first imaginary circle 50c. This ensures the effect of suppressing heat generation by the first non-arc portion 53. Note that the above "length of the first non-arc portion 53 in the first circumferential direction" refers to the length of the first non-arc portion 53 in the first circumferential direction when the first non-arc portion 53 is projected onto the first imaginary circle 50c outward in the first radial direction.

[0068] Since the first rotor 50 is provided so as to extend in the axial direction Z (see FIG. 4), it is preferable that the above [Condition α2] be satisfied at least at a portion of the first rotor 50 in the axial direction Z.

[0069] It is preferable that the second arc-shaped portion 61 of the second rotor 60 satisfies the same condition as the above-mentioned [Condition α2]. That is, the length of the second arc-shaped portion 61 that extends continuously in the second circumferential direction is preferably 3 / 4 or less of the entire circumferential length of the second virtual circle 60c. When the first arc-shaped portion 51 satisfies the above-mentioned [Condition α2], it is preferable that the second arc-shaped portion 61 satisfies the same condition as the above-mentioned [Condition α2]. When the first arc-shaped portion 51 satisfies the above-mentioned [Condition α2], the second arc-shaped portion 61 does not have to satisfy the same condition as the above-mentioned [Condition α2].

[0070] (Torsion angle conditions) FIG. 6 shows a development of the first rotor 50 (of the first outer peripheral portion 50e). This development of the first rotor 50 is a development of the first outer peripheral portion 50e projected onto a virtual cylinder (not shown) around the first rotor 50 shown in FIG. 2, and the virtual cylinder is developed. In detail, a virtual cylinder is defined as a virtual cylinder whose center is the first rotation axis 50a and whose cross section viewed from the axial direction Z overlaps with the first virtual circle 50c. The first outer peripheral portion 50e is projected outward in the first radial direction onto this virtual cylinder. The virtual cylinder onto which the first outer peripheral portion 50e is projected is opened by a straight line on the outer circumferential surface of this virtual cylinder that extends in the axial direction Z, and the figure is shown in a plane. The figure shown in this plane is the development of the first rotor 50 shown in FIG. 6.

[0071] The length of the first rotor 50 in the axial direction Z (the direction in which the first rotating shaft 50a (see FIG. 4) extends) is defined as a first axial length L. The radius of the first virtual circle 50c (see FIG. 2) is defined as a first radius R. The angle between the axial direction Z and the direction in which the first non-arc portion 53 extends (more specifically, the direction in which the center line C53 of the first non-arc portion 53 extends) is defined as a first twist angle θ. The center line C53 is a line connecting the center positions of the first non-arc portion 53 in the first circumferential direction (the center position of the first inter-convex recess 53b1 in the first circumferential direction in the example shown in FIG. 2).

[0072] As the first twist angle θ increases, the area in the first circumferential direction where only the first arc portion 51 exists (arc portion area E1) becomes smaller, and the area in the first circumferential direction where the first non-arc portion 53 exists (non-arc portion area E3) becomes larger. Thus, the heat generation suppression effect increases. On the other hand, as the first twist angle θ decreases, the non-arc portion area E3 becomes smaller and the arc portion area E1 becomes larger, and the effect of applying high stress increases.

[0073] Specifically, the first twist angle θ preferably satisfies the following formula (1). Moreover, the first twist angle θ preferably satisfies formula (2). The first twist angle θ more preferably satisfies formula (3). Formula (3) is a formula that satisfies the conditions of both formulas (1) and (2).

[0074] tan -1 (πR / 4L)≦θ (1) θ≦tan -1 (πR / 2L) (2) tan -1 (πR / 4L)≦θ≦tan -1 (πR / 2L) (3)

[0075] When the first twist angle θ satisfies formula (1), the non-circular portion region E3 is secured. When formula (1) is satisfied, the length (Ltanθ) of the center line C53 of the first non-circular portion 53 in the first circumferential direction in the development view of the first rotor 50 is πR / 4 or more. In this case, a heat generation suppression effect is obtained compared to the case where the first twist angle θ does not satisfy formula (1).

[0076] When the first helix angle θ satisfies formula (2), the arc region E1 is secured. When formula (2) is satisfied, the length (Ltanθ) in the first circumferential direction of the center line C53 of the first non-arcuate portion 53 in the development view of the first rotor 50 is equal to or less than πR / 2. In this case, a high stress application effect can be obtained compared to when the first helix angle θ does not satisfy formula (2).

[0077] When formula (3) is satisfied for the first twist angle θ, the arc region E1 and the non-arcuate region E3 are secured. When formula (3) is satisfied, in the development view of the first rotor 50, the length (Ltanθ) in the first circumferential direction of the center line C53 of the first non-arcuate portion 53 is equal to or larger than πR / 4 and equal to or smaller than πR / 2. In this case, it is possible to achieve both the effect of suppressing heat generation and the effect of applying high stress.

[0078] When the first rotor 50 (the first helix angle θ) satisfies formula (1), formula (2), or formula (3), it is preferable that the second rotor 60 (see FIG. 2) also satisfies the same condition as formula (1), formula (2), or formula (3) above. When the first rotor 50 (the first helix angle θ) satisfies formula (1), formula (2), or formula (3), the second rotor 60 does not have to satisfy formula (1), formula (2), or formula (3) above.

[0079] (Effects of the first invention) The effects of the kneading device 1 shown in FIG. 1 are as follows. The kneading device 1 includes a kneading chamber 10a, a first rotor 50, and a second rotor 60. The kneading chamber 10a is a portion for kneading materials in the presence of a working fluid in a supercritical state or a subcritical state. The first rotor 50 is disposed inside the kneading chamber 10a and rotates around a first rotating shaft 50a. The second rotor 60 is disposed inside the kneading chamber 10a, is disposed parallel to the first rotor 50, is disposed adjacent to the first rotor 50, and rotates around the second rotating shaft 60a in the opposite direction to the rotation direction of the first rotor 50.

[0080] [Configuration 1-1] The first rotor 50 has a first outer circumferential portion 50e. The first outer circumferential portion 50e is an outer circumferential portion of a cross section of the first rotor 50 as viewed from the direction in which the first rotating shaft 50a extends (axial direction Z). The first outer circumferential portion 50e has a first arc portion 51 and a first non-arc portion 53. The first non-arc portion 53 is a portion of the first outer circumferential portion 50e that is different from the first arc portion 51. A virtual circle that passes through the first arc portion 51 and has its center on the first rotating shaft 50a when viewed from the direction in which the first rotating shaft 50a extends (axial direction Z) is defined as a first virtual circle 50c.

[0081] [Configuration 1-2] The first arc portion 51 has an arc shape centered on the first rotating shaft 50a, and is disposed at the radially outermost portion of the first rotor 50.

[0082] [Configuration 1-3] The first arcuate portion 51 extends continuously in the circumferential direction of the first rotor 50 (first circumferential direction) over at least ⅓ of the entire circumferential length of the first imaginary circle 50c.

[0083] [Configuration 1-4] The second rotor 60 has a second outer circumferential portion 60e. The second outer circumferential portion 60e is an outer circumferential portion of a cross section of the second rotor 60 as viewed from the direction in which the second rotating shaft 60a extends (axial direction Z). The second outer circumferential portion 60e has a second arc portion 61 and a second non-arc portion 63. The second non-arc portion 63 is a portion of the second outer circumferential portion 60e that is different from the second arc portion 61. A virtual circle that passes through the second arc portion 61 and has its center on the second rotating shaft 60a when viewed from the direction in which the second rotating shaft 60a extends (axial direction Z) is defined as a second virtual circle 60c.

[0084] [Configuration 1-5] The second arc portion 61 is arc-shaped with the second rotating shaft 60a as the center, and is disposed at the radially outermost portion of the second rotor 60.

[0085] [Configuration 1-6] The second arc portion 61 extends continuously in the circumferential direction of the second rotor 60 (second circumferential direction) over at least ⅓ of the entire circumferential length of the second imaginary circle 60c.

[0086] [Configuration 1-7] Between the first rotating shaft 50a and the second rotating shaft 60a (rotor shaft region A), there is a timing when the first non-circular portion 53 and the second circular portion 61 face each other.

[0087] According to the above [Configuration 1-2] and [Configuration 1-5], as shown in FIG. 3, when the first arc portion 51 and the second arc portion 61 face each other, the gap (arc portion gap A1) between the first arc portion 51 and the second arc portion 61 tends to become narrow. In addition, in the above [Configuration 1-3] and [Configuration 1-6], the length of each of the first arc portion 51 and the second arc portion 61 is ensured. Therefore, when the first arc portion 51 and the second arc portion 61 face each other, high stress can be applied to the material when the material passes through the arc portion gap A1. Therefore, the first rotor 50 and the second rotor 60 can apply high stress to the material.

[0088] The above [Configuration 1-7] provides the following effect. As shown in Fig. 1, when the second arc portion 61 and the first non-arcuate portion 53 face each other, the gap between the second arc portion 61 and the first non-arcuate portion 53 (arcuate portion-non-arcuate portion gap A3) is wider than the arc portion gap A1 (see Fig. 3). Therefore, when the material passes through the arc portion-non-arcuate portion gap A3, heat generation from the material can be suppressed.

[0089] Therefore, the kneading device 1 can suppress heat generation from the material in the rotor 40 (the first rotor 50 and the second rotor 60) that can impart high stress to the material.

[0090] (Effects of the second invention) As shown in FIG. 4, the first non-circular portion 53 has a shape (first twisted portion 53c) twisted around the first rotating shaft 50a so as to extend in a direction inclined relative to the first rotating shaft 50a. As shown in FIG. 6, the length of the first rotor 50 in the direction in which the first rotating shaft 50a extends (axial direction Z) is defined as a first axial length L. The radius of the first virtual circle 50c (see FIG. 1) is defined as a first radius R. The angle between the direction in which the first rotating shaft 50a extends (axial direction Z) and the direction in which the first non-circular portion 53 extends is defined as a first twist angle θ. In this case, the following formula is satisfied.

[0091] [Configuration 2]tan -1 (πR / 4L)≦θ≦tan -1 (πR / 2L)

[0092] The above-mentioned [Configuration 2] makes it possible to ensure, in first outer circumferential portion 50e, a region in the first circumferential direction where only first arc-shaped portion 51 exists (arc-shaped portion region E1), and a region in the first circumferential direction where first non-arc-shaped portion 53 exists (non-arc-shaped portion region E3). Therefore, it is possible to obtain a well-balanced effect between the effect of applying high stress to the material and the effect of suppressing heat generation from the material.

[0093] (Effects of the third invention) [Configuration 3] As shown in FIG. 1, the length of the first arc portion 51 that extends continuously in the circumferential direction (first circumferential direction) of the first rotor 50 is 3 / 4 or less of the entire circumference of the first imaginary circle 50c.

[0094] The above [Configuration 3] provides the following effects. In the above [Configuration 1-3], the first arc portion 51 extends continuously in the first circumferential direction for at least 1 / 3 of the total circumferential length of the first virtual circle 50c. If the first arc portion 51 is too long, the first non-arc portion 53 becomes too small, and the effect of suppressing heat generation in the material is limited. Therefore, in the above [Configuration 3], the length of the first arc portion 51 that extends continuously in the first circumferential direction is 3 / 4 or less of the total circumferential length of the first virtual circle 50c. Therefore, the size of the first non-arc portion 53 can be ensured. Therefore, the effect of suppressing heat generation in the material can be ensured.

[0095] Second embodiment A kneading device 201 of the second embodiment will be described in terms of differences from the first embodiment with reference to Fig. 7. Note that, of the kneading device 201 of the second embodiment, a description of the commonalities with the first embodiment will be omitted.

[0096] In the example shown in Fig. 2, the first non-arcuate portion 53 includes a first convex portion 53a and a first concave portion 53b. Meanwhile, as shown in Fig. 7, the first non-arcuate portion 253 may include a first concave portion 253b and not include the first convex portion 53a (see Fig. 2). As with the first rotor 50, the second non-arcuate portion 263 of the second rotor 60 may include a second concave portion 263b and not include the second convex portion 63a (see Fig. 2).

[0097] The first recess 253b may have any shape (the same goes for the second recess 263b). In the example shown in Fig. 9, the first recess 253b has an arc shape recessed inward in the first radial direction, and is a circular arc shape or a substantially circular arc shape.

[0098] (Modification) The above embodiment may be modified in various ways. For example, components (including modified examples) of different embodiments may be combined with each other. For example, modified examples of the above embodiment may be combined with each other in various ways. For example, the number of components (including modified examples) of the above embodiment may be changed, or some of the components may not be provided. For example, the arrangement of the components may be changed. For example, the inclusion relationship of the components may be changed in various ways. For example, a component described as a lower component included in a higher component may not be included in this higher component, and may be included in another component. For example, a component described as multiple different members or parts may be treated as a single member or part. For example, a component described as a single member or part may be provided separately as multiple different members or parts. For example, each component may have only a part of each feature (function, arrangement, shape, operation, etc.).

[0099] 2 may include only one first protruding portion 53a. Alternatively, the first rotor 50 may include two first non-circular portions 53 (at two locations). [Explanation of symbols]

[0100] 1, 201 Kneading device 10a Mixing room 50 First rotor 50a First rotating shaft 50c First Imaginary Circle 50e First outer periphery 51 First arc 53 First non-circular arc section 60 Second rotor 60a Second Rotating Axis 60c Second imaginary circle 60e Second outer periphery 61 Second arc 63 Second non-circular section L First axis length R first radius θ First twist angle

Claims

1. A kneading chamber in which the material is kneaded in the presence of a working fluid in a supercritical state or a subcritical state; A first rotor is disposed inside the kneading chamber and rotates around a first rotation axis; A second rotor is disposed inside the kneading chamber, is disposed parallel to the first rotor, is disposed adjacent to the first rotor, and rotates about a second rotation axis in a direction opposite to a rotation direction of the first rotor; Equipped with the first rotor includes a first outer circumferential portion that is an outer circumferential portion of a cross section of the first rotor as viewed from a direction in which the first rotation shaft extends, The first outer circumferential portion is A first arcuate portion; a first non-circular portion that is a portion of the first outer circumferential portion that is different from the first circular arc portion; Equipped with When viewed from the extension direction of the first rotation shaft, a virtual circle that passes through the first arc portion and has the first rotation shaft as its center is defined as a first virtual circle, the first arc portion has an arc shape centered on the first rotation axis, is disposed at a radially outermost portion of the first rotor, and extends continuously in a circumferential direction of the first rotor for one-third or more of a total circumference length of the first virtual circle; the second rotor includes a second outer circumferential portion that is an outer circumferential portion of a cross section of the second rotor as viewed from a direction in which the second rotation shaft extends, The second outer circumferential portion is A second arcuate portion; a second non-circular portion that is a portion of the second outer circumferential portion that is different from the second circular arc portion; Equipped with When viewed from the extension direction of the second rotation shaft, a virtual circle that passes through the second arc portion and has the second rotation shaft as its center is defined as a second virtual circle, the second arc portion has an arc shape centered on the second rotation axis, is disposed at the radially outermost portion of the second rotor, and extends continuously in a circumferential direction of the second rotor for at least one-third of a total circumference of the second virtual circle; There is a timing at which the first non-circular portion and the second circular portion face each other between the first rotation shaft and the second rotation shaft. Kneading equipment.

2. The kneading device according to claim 1, the first non-circular portion has a shape twisted about the first rotation axis so as to extend in a direction inclined with respect to the first rotation axis, The length of the first rotor in the direction in which the first rotation shaft extends is defined as a first axial length L, The radius of the first virtual circle is a first radius R, The angle between the direction in which the first rotation axis extends and the direction in which the first non-circular portion extends is defined as a first torsion angle θ. When <h2 style=";text-align:left;direction:ltr">tan<h2 style=";text-align:left;direction:ltr"> -1 <h2 style=";text-align:left;direction:ltr"> (πR / 4L)≦θ≦tan<h2 style=";text-align:left;direction:ltr"> -1 <h2 style=";text-align:left;direction:ltr"> (πR / 22L) Fulfilling Kneading equipment.

3. The kneading device according to claim 1, a length of the first arc portion that extends continuously in a circumferential direction of the first rotor is 3 / 4 or less of a total circumference of the first virtual circle; Kneading equipment.

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