JP4085957B2 - Closed kneader - Google Patents

Description

  The present invention relates to a closed kneader for kneading a material such as rubber or plastic inside a sealed chamber.

  Patent Document 1 describes a non-engagement type closed kneader. As shown in FIG. 6, this kneader is provided with two rotors 52 inside a sealed chamber 51, a pair of long and short blades 53 projecting from each rotor 52, and the rotors 52 in opposite directions. The material M rotates and the material M is kneaded by the rotation of the blades 53. Patent Document 2 describes a technique for changing a gap (tip clearance) between a chamber and a rotor in a rotor axial direction according to the shape of a blade in a non-meshing kneader.

Patent Document 3 describes a meshing kneader. In this kneader, as shown in FIG. 7, two noches 57 having different lengths are projected from two rotors 56, and one of the noches 57 is formed so as to extend spirally over the entire length of the rotor 56. The rotors 56 are rotated in opposite directions, and the materials are kneaded by meshing with the nogs 57.
Japanese Patent Publication No. 4-55363 JP 11-482239 A Japanese National Patent Publication No. 11-504666

  However, according to the conventional non-meshing kneader, as shown in FIG. 6A, the material M may stay in the portion P1 where the blades 53 do not reach between the two rotors 52 depending on the type. There is a problem that the material of this part cannot be sufficiently compressed and sheared, and the dispersibility of the compounding agent is lowered. On the other hand, the meshing type kneader can repeatedly compress and shear the material M passing between the two rotors 56 by the meshing of the nogs 57 to increase the dispersibility of the compounding agent.

  However, in the conventional mesh type kneader, as shown in FIG. 7 (b), the longest nog 57 extends the entire length of the rotor 56. In this case, the compounding agent could not sufficiently pass through part P2, and the compounding agent sometimes stayed in an undispersed state. In addition, since both types of kneaders are provided with a plurality of long or short blades or nogs in one rotor, the material tends to drift to one side in the rotor axial direction along the longer blades or nogs. There is a problem that the distribution of the kneaded material becomes insufficient and the material of the kneaded dough becomes non-uniform.

  The object of the present invention is to provide a meshing type closed kneading that solves the above problems, prevents material stagnation and drift, efficiently compresses and shears, increases the dispersion of the compounding agent, and provides a homogeneous kneaded dough. Is to provide a machine.

In order to solve the above-described problems, the present invention provides a closed kneading machine in which two rotors rotate inside a sealed chamber and the nogs projecting from the rotors mesh with each other. Are arranged in a phase separated from each other by approximately 180 ° and are formed in a spiral shape with a predetermined twist angle that is symmetrical in the left-right direction in the rotor axis direction, and the end faces on the front side in the rotational direction substantially start from the edge of the rotor. The end surface on the rear side in the rotational direction is formed so as to end without reaching the opposite edge of the rotor, and the material passage is formed on the rotor at the portion that does not reach, and the wall surface on the front side in the rotational direction of the noggs has an inclination angle of 35. It is characterized by having a material biting surface of ° to 55 ° . It is preferable that the nose of the mating rotor is engaged between the end face on the rear side in the rotation direction of one of the rotors and the wall surface on the front side in the rotation direction of the other nog.

  Here, the closed-type kneader is not limited to a specific application. For example, the main material of rubber or plastic and a compounding agent (plasticizer, vulcanizer, colorant, etc.) are kneaded, or the main material alone. It can be used for kneading (eg, plasticizing kneading of rubber). Design items such as the structure and capacity of the chamber and the diameter and length of the rotor are not particularly limited, and can be appropriately determined according to the type of material or the kneading conditions.

  The shape of the rotor nog has a great influence on the compression and shearing of the material. In the present invention, the two nogs are formed in a spiral shape with a predetermined torsional angle that is bilaterally symmetric in the axial direction of the rotor. Therefore, the lengths and widths of the two nogs are substantially equal and the directions are opposite to each other. For this reason, the material flows equally between the chamber and the rotor and between the two rotors as the rotor rotates. Therefore, the material is subjected to uniform compression / shearing action in the rotor axial direction, and the compounding agent is efficiently dispersed.

  Also, each nog is formed so that the end surface on the front side in the rotation direction starts from the end edge of the rotor, but the end surface on the rear side in the rotation direction ends without reaching the end edge on the opposite side of the rotor. Since the material passage is on the rotor, the material does not stay at the end of the nog in the rear side in the rotation direction. In addition, if the nose of the mating rotor meshes between the end surface on the rear side in the rotation direction of one of the rotors of each rotor and the wall surface on the front side in the rotation direction of the other noggle (including the material passage), the entire amount of material remains. It is possible to reliably prevent undispersion of the compounding agent by compressing and shearing.

With respect to the nog shape, the present invention proposes further advantageous shapes as follows.
(1) The torsion angle of the nog is set to 35 ° to 55 °. The twist angle is an angle between a straight line perpendicular to the edge of the rotor and the nog. When the twist angle is in the range of 35 ° to 55 °, and more preferably in the range of 40 ° to 50 °, the amount of axial movement of the material and the amount of passage through the top of the nog are almost equal, and a well-balanced dispersion / distribution function is achieved. can get. When the twist angle is less than 35 °, the amount of axial movement of the material decreases, and the amount of passage through the top surface of the nog increases. If the twist angle exceeds 55 °, the amount of axial movement of the material increases and the amount of passage through the top surface of the nog decreases. For this reason, in both cases, the balance between the distribution and distribution functions is lost.

(2) As already described as a feature of the present invention, the wall surface on the front side in the rotation direction of the nogging is a material biting surface having an inclination angle of 35 ° to 55 °. The inclination angle is an angle between the cylindrical surface of the rotor and the wall surface on the front side in the rotation direction of the nog, and means an angle at which the nog bites into the material. When this inclination angle (biting angle) is in the range of 35 ° to 55 °, more preferably 40 ° to 50 °, the material is efficiently compressed and sheared, and the dispersion of the compounding agent is promoted. When the inclination angle is less than 35 °, excessive compressive / shear stress is generated in the material, and the material may be adversely affected by heat generation. When the inclination angle exceeds 55 °, the compression / shearing action becomes insufficient and the dispersion of the compounding agent tends to occur.

(3) The top surface of the nog is stepped. Although it does not specifically limit as a stepped shape, The thing by having formed the recessed part (preferably several) extended in the width direction of the top surface of a nog can be illustrated. If the stepped shape is adopted, the flow of the material passing through the top surface of the nog changes, so that a shearing action can be applied to more materials to increase the dispersibility of the compounding agent.

  Therefore, according to the closed-type kneader according to the present invention, excellent effects of preventing material stagnation and drift, efficiently compressing and shearing, increasing the dispersibility of the compounding agent, and obtaining a homogeneous kneaded dough. Play.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings. As shown in FIG. 1, the closed kneader includes a casing 2 on a base 1, and a chamber 3 is sealed with the casing 2. Above the chamber 3, a hopper door 4 for feeding the material, a weight 5 for pushing the material into the chamber 3, and a cylinder 6 for lifting and lowering the weight 5 are disposed. Two rotors 7 for kneading the material are provided inside the chamber 3, and a drop door 8 for taking out the kneaded dough after the kneading is provided below the chamber 3.

  As shown in FIGS. 2 and 3, the two rotors 7 are supported by the casing 2 in a state of facing each other in parallel, and are rotated in opposite directions by a motor via gears (not shown). Two spiral nogs 10 project from the cylindrical surface of each rotor 7, and as the rotor 7 rotates, the nogs 10 of one rotor 7 mesh with the nogs 10 of the mating rotor 7. Yes. The material M is compressed and sheared by the rotation of the nog 10 between the chamber 3 and the rotor 7 and the engagement of the nog 10 between the rotors 7, and the compounding agent is kneaded into the main material. It is.

  As shown in FIG. 4 (a), the cylindrical surface of the rotor 7 is developed, and the two nogs 10 are arranged with a phase 180 degrees away from each other and are symmetrical with respect to the rotor axial direction (left-right direction in the figure). It is formed in a spiral shape with a predetermined twist angle. Specifically, in the figure, the upper nog 10 has an end surface 11 on the front side in the rotational direction starting from the right end edge of the rotor 7 and extending to the rear side in the rotational direction at a twist angle of 45 ° therefrom, and an end surface 12 on the rear side in the rotational direction is It is formed so as to end without reaching the left end edge of the rotor 7, and the material passage 20 is formed on the rotor 7 in a portion where the rotor 7 does not reach. The lower nog 10 is arranged at a phase 180 ° away from the upper nog 10, and the end surface 11 on the front side in the rotational direction starts from the left end edge of the rotor 7, and then the rear side in the rotational direction at a twist angle of 45 ° The end surface 12 on the rear side in the rotational direction is formed so as to end without reaching the right end edge of the rotor 7, and the material passage 20 is formed on the rotor 7 at the portion that does not reach. Then, as shown in FIG. 4B, the nog 10 of the counterpart rotor 7 is between the end surface 12 on the rear side in the rotation direction of the upper nog 10 and the wall surface 13 on the front side in the rotation direction of the lower nog 10. It comes to mesh. The width of the material passage 20 is not particularly limited, but it is preferable that the width of the material passage 20 is not less than the extent that the mating nog 10 can be engaged as described above. The length of the nog 10 is set to the maximum value that can secure the width of the material passage 20.

  Further, the wall surface 13 on the front side in the rotation direction of the nog 10 is a material biting surface having an inclination angle of 45 ° (see FIG. 3). The top surface 15 of the nog 10 has a stepped shape due to the formation of a plurality of recesses 16 extending in the width direction (direction perpendicular to the longitudinal direction) of the top surface 15. The depth of the recess 16 is not particularly limited, but is preferably about half of the gap between the inner surface of the chamber 3 and the top surface 15 of the nog 10 (for example, when the gap is 3 mm, the depth of the recess 16 is 1.5 mm). . The meshing gap between the nogs 10 is not particularly limited, but may be, for example, about the same as the gap between the chamber 3 and the nogs 10 (for example, 3 mm). The wall surface 14 on the rear side in the rotation direction of the nog 10 is not particularly limited in terms of shape, inclination angle, or the like as long as it does not interfere, and may be, for example, a curved surface, an inclined surface, or an upright surface.

According to the closed kneader having the above-described configuration, the following effects can be obtained.
(A) Since the two nogs 10 are formed symmetrically in the axial direction of the rotor 7, the lengths and widths of the nogs 10 are equal and the directions are reversed from side to side. Therefore, the material M passes between the chamber 3 and the rotor 7 through the top surface 15 of the nog 10 at a uniform flow rate as shown in FIG. As shown in b), the direction is changed regularly and flows equally to the left and right. Therefore, each part of the material M can be uniformly compressed and sheared, and the compounding agent can be dispersed efficiently.

(B) The end face 12 on the rear side in the rotation direction of each nog 10 is formed so as to end without reaching the end edge of the rotor 7, and the material passage 20 is formed on the rotor 7 at the part that does not reach The material M does not stay in the vicinity of the end portion on the rear side in the rotation direction of the nog 10, and the undispersed ingredients are not generated.
(C) The nogg of the mating rotor 7 is located between the end surface 12 on the rear side in the rotation direction of one of the rotors 7 of each rotor 7 and the wall surface 13 on the front side in the rotation direction of the other nog 10 (including the material passage 20). Since 10 meshes, the entire amount of the material M is compressed and sheared, and the dispersibility of the compounding agent can be increased.

(D) Since the twist angle of the nog 10 is set to 45 °, the amount of movement of the material M in the rotor axial direction and the amount of passage of the nog 10 through the top surface 15 are almost equal, and a well-balanced distribution / distribution function is achieved. can get.
(E) Since the wall surface 13 on the front side in the rotation direction of the nog 10 is a material encroaching surface having an inclination angle of 45 °, the material M is compressed by the wedge action of the wall surface 13 as shown in FIG. Then, it is guided to the top surface 15 of the nog 10 and is efficiently sheared by the gap between the nog 10 and the chamber 3. As a result, the dispersion of the compounding agent between the chamber 3 and the rotor 7 can be particularly promoted.
(F) Since the top surface 15 of the nog 10 has a stepped shape by the recess 16, the flow of the material M passing through the top surface 15 of the nog 10 changes as shown in FIG. Therefore, it is possible to increase the degree of dispersion of the compounding agent by giving a shearing action to more materials M.

  FIG. 5 shows experimental results for confirming the above effects. Here, the product of the present invention is a kneaded dough by the rotor 7 of the above-described embodiment provided with two nogs 10, and the conventional product is by a conventional rotor 56 provided with three nogs 57 (see FIG. 7). It is a kneaded dough. Replace the rotors 7 and 56 with the same kneader having a chamber capacity of 1.3 liters, and operate the kneader at a cylinder air pressure of 0.46 MPa, a chamber temperature of 60 ° C., and a rotor speed of 39 rpm. did. As materials, EPDM rubber was used as the main material, carbon powder was used as the compounding agent, the main material was masticated, the compounding agent was added in a lump, and the present product and the conventional product were kneaded at the same time. And the filling rate of material was changed, the several kneaded material | dough sample was acquired, and the average particle diameter of the compounding agent in each sample and the fracture | rupture elongation rate of material | dough were measured.

  As shown to Fig.5 (a), the average particle diameter which shows the dispersion degree of a compounding agent (carbon powder) was 10-12 micrometers for this invention goods, and 18-20 micrometers for the conventional goods. From this result, according to the nog shape of the present invention, it was confirmed that the dispersion degree of the compounding agent was improved to about twice that of the conventional one. As shown in FIG.5 (b), the breaking elongation rate which shows the distribution degree of a compounding agent was 300-320% of this invention products, and 280-310% of the conventional products. From this result, according to the nog shape of the present invention, it was confirmed that the compounding agent was sufficiently distributed, and a kneaded dough more homogeneous than the conventional product was obtained.

In addition, this invention is not limited to the said embodiment, For example, it can also be suitably changed and embodied as follows, for example in the range which does not deviate from the meaning of invention.
(1) The twist angle of the nog 10 is set to around 40 ° or around 50 °.
(2) The inclination angle of the wall surface 13 on the front side in the rotational direction is set to around 40 ° or around 50 °.
(3) The concave portion 16 of the top surface 15 of the nog 10 is formed in a sawtooth shape or a waveform.

1 is an overall view of a closed kneader showing an embodiment of the present invention. It is sectional drawing which shows the rotor of the kneading machine of FIG. FIG. 3 is a front view of the rotor of FIG. 2. FIG. 4 is a development view of the rotor of FIG. 3. It is a characteristic view which compares the physical-property value of this invention and the conventional kneaded material | dough. It is the schematic which shows the rotor of the conventional non-meshing type kneader. It is the schematic which shows the rotor of the conventional meshing-type kneader.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Chamber 7 Rotor 10 Nog 11 End surface of rotation direction front side 12 End surface of rotation direction rear side 13 Wall surface of rotation direction front side 14 Wall surface of rotation direction rear side 15 Top surface 16 Recessed part 20 Material path

Claims (5)

In a closed kneader in which two rotors rotate inside a sealed chamber and the nogs protruding from each rotor mesh with each other.
Two noses are arranged on each rotor at a phase approximately 180 ° apart from each other, and are formed in a spiral shape with a predetermined twist angle that is bilaterally symmetrical with respect to the rotor axial direction. Although substantially starting from the edge, the end face of the rotation direction rear side is formed to end up not reach the opposite edge of the rotor, the upper rotor portion or no該届the material path, the rotation direction front side of the Nog A closed-type kneader characterized in that the wall surface is a material biting surface with an inclination angle of 35 ° to 55 ° .   The hermetic kneading machine according to claim 1, wherein the nose of the mating rotor meshes between the end face on the rear side in the rotation direction of one of the rotors and the wall surface on the front side in the rotation direction of the other noggle.   The hermetic kneader according to claim 1 or 2, wherein a twist angle of the nogg is set to 35 ° to 55 °. The hermetic kneader according to any one of claims 1 to 3, wherein a top surface of the nog is stepped . The hermetic kneader according to claim 4, wherein the stepped shape is formed by forming a recess extending in the width direction of the top surface of the nog .

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