JP2004351930A - Multiscrew kneading device and method of kneading material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiscrew kneading device having a plurality of screws and functions for conveying and kneading materials and also a method of kneading the materials. <P>SOLUTION: The multiscrew kneading device kneads materials at a kneading part 120 and conveys them while the materials are moved and mixed together at a material supply conveying part 110 and a material discharge conveying part 130. Thereby, the bubbles potentially mingled in the materials can be fully removed, enabling to enhance material kneading performance compared with traditional devices. The device also has a material return part 140 enabling the evaluation of the physical properties of the materials to be made in a small quantity of them. Accordingly, compared with the conventional devices, the present device allows materials to be more efficiently and fully kneaded in addition to having the material conveying function. The method of kneading the materials is also disclosed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multi-axis kneading apparatus and a material kneading method having a plurality of screws and a material kneading member for kneading a material and extruding the material.

2. Description of the Related Art Conventionally, there is a mixer device called “Measuring Mixers” as a device for testing the processability of a small amount of a material such as a thermoplastic resin or a thermosetting resin, such as kneading properties. The mixer device includes a gear unit having a blade for mixing the materials, and can knead a small amount of the materials for a long time. (For example, see Non-Patent Document 1.)
Brabender OHG, "Measuring Mixers", [online], Brabender OHG homepage, [Search April 22, 2003], Internet <URL: http://www.brabender.de/2_2_1.html>

  However, the mixer has no mechanism for transporting the mixed material, and the processed material must be taken out of the mixer as a lump, which poses a problem in handling the material. In addition, since the mixer simply mixes the materials, even if the kneadability of the materials is evaluated by the mixer, if the scale is increased to an extruder having a screw-conveying function, the above mixer is used. It is difficult to obtain the same evaluation as.

  In order to improve the handleability of the material, it is conceivable to add the transport mechanism by providing a screw structure provided in a so-called extruder in the mixer device. However, when a transfer mechanism having a screw structure in which the gap between the screw and the casing is narrowed is provided, a material flows in one direction in the path, so that a material discharge port is required for the material input port. Become. Since addition of only a short-distance transport mechanism does not provide sufficient melt-kneading, there is a problem that a large load is applied to the apparatus. Therefore, even if the above-described transport mechanism is added, good material kneading properties cannot be obtained. On the other hand, if the length of the transport mechanism is increased, the structure becomes the same as that of a so-called extruder, and a large amount of material is required.

  Also, in place of the screw structure, even if a material kneading member called kneading is provided in the mixer device, the material kneading member alone may cause the material to be unevenly distributed or left in some places in the device. The device tends to be overloaded, or it is difficult to remove air bubbles mixed in the material, so that good material kneading properties cannot be obtained.

On the other hand, in order to increase the material kneading property by using only the extruder as in the case of the above mixer, it is necessary to lengthen the kneading portion, that is, lengthen the screw shaft. However, an increase in the screw shaft length causes a problem that a large amount of material is charged as described above. For example, materials for so-called nanotechnology in recent years have a very high unit price, and it is economically difficult to use materials in excess of the required amount. Further, a method of reducing the processing amount using an ultra-small extruder is also conceivable, but even in this case, it is difficult to perform processing with a material amount on the order of several grams.
It is also conceivable to use an extruder having a short axis length, to put the material which has been kneaded, discharged from the extruder and once taken out into the material supply section again and kneaded repeatedly. However, in this method, when the material is taken out from the extruder, the heat history acting on the material, such as cooling, solidification, re-melting, kneading, etc., changes, and the physical properties of the material cannot be accurately evaluated. .
The present invention has been made in order to solve the above-described problems, and has a plurality of screws, a multi-axis kneading apparatus having a material conveying function and a kneading function, and a multi-axis kneading apparatus. It is an object to provide a material kneading method to be performed.

To achieve the above object, the present invention is configured as follows.
That is, the multi-axis kneading apparatus according to the first aspect of the present invention includes a plurality of first conveying members meshed with each other in a screw shape and arranged in parallel with each other, and a material supply unit for a material to be kneaded. A material supply / conveyance unit configured to convey the material in a conveyance direction along an axial direction of the first conveyance member by rotation of the first conveyance member;
A kneading unit having a kneading member that is connected to the material supply / transport unit along the axial direction and kneads the material conveyed by the material supply / transport unit,
A plurality of second conveying members connected to the kneading section along the axial direction, meshed with each other in a screw shape, and arranged in parallel with each other, and the material kneaded in the kneading section is subjected to the second conveyance. A discharge conveyance unit that conveys to the material discharge port by rotation of the member for discharging,
A material return section connected to the material discharge port and supplying the material discharged from the material discharge port to the material supply / conveyance section again;
It is characterized by having.

  Further, the material return section has a material return pipe for supplying the material discharged from the material discharge port to the material supply / transport section again, and the material return pipe is provided immediately before the kneading section. At least one or more threads in the first transport member may be connected to the material supply transport section at a return position away from the kneading section.

  The material return section may further include a sampling section provided immediately before the return position in the material return pipe and sampling the material returned to the material supply / transport section through the material return pipe from the material return pipe. Can also be configured.

  Further, the material return section may be configured to further include a measuring device provided in the material return pipe and measuring a physical quantity in the material return pipe of the material returned to the material supply / conveyance section.

  In addition, the material return portion may be configured to further include a test piece preparation mold portion that is provided in the material return tube and that prepares a test piece of the material with the material that stays in the material return tube. .

  In addition, a switching unit provided at the material discharge port and configured to supply the material discharged from the material discharge port to one of the material return unit and the die for molding the material may be further provided.

  Further, the apparatus may further include a temperature control device for performing at least one of heating and cooling of the material during transport and kneading of the material.

  In addition, the apparatus may further include a gas removal unit provided in the discharge conveyance unit and configured to remove gas from the material.

  Further, a liquid supply unit which is provided in at least one of the material supply / conveyance unit and the discharge conveyance unit and supplies the liquid to the material may be further provided.

  In addition, the apparatus may further include a gas supply unit provided in the material supply / transport unit and configured to supply gas to the material.

  Further, a seal unit having a screw-shaped seal member having a reverse screw structure with respect to the second transport member may be further provided between the kneading unit and the discharge transport unit.

Further, in the material kneading method according to the second aspect of the present invention, the supplied material is transported by a screw-shaped first transporting member in a transporting direction along the axial direction of the first transporting member,
Kneading the above-mentioned materials that have been conveyed,
The kneaded material is transported to the material outlet by a screw-shaped second transport member,
The material discharged from the material discharge port is returned to the first conveying member again through the material return pipe to repeatedly knead the material.
It is characterized by the following.

  Further, in the material kneading method, the material is returned by the material return pipe by returning at least one crest in the thread of the first conveying member installed immediately before the material kneading operation, which is separated from the material kneading operation. You may make it return to a position.

  As described above in detail, according to the multiaxial kneading apparatus of the first aspect and the material kneading method of the second aspect of the present invention, the material can be repeatedly kneaded in the kneading section, and the material supply / conveyance section and the discharge The material can be transported while being moved by the transporting unit, and the material is not unevenly distributed to a specific place. Further, in the above movement, the materials are conveyed while being mixed, so that air bubbles that may be mixed in the materials can be sufficiently removed, and the material kneading property can be improved as compared with the conventional apparatus. . Further, the provision of the material return section makes it possible to prevent the kneading apparatus from being lengthened, and to evaluate the kneading operation of a material having a material conveying function with a small amount of material. Therefore, according to the multi-axis kneading apparatus of the present embodiment, the material can be efficiently and sufficiently kneaded while having a material conveying function as compared with the conventional apparatus.

  Further, by providing the switching section, the kneaded material can be taken out of the apparatus, and can be formed and taken out by passing through a base.

A multi-axis kneading apparatus according to an embodiment of the present invention and a material kneading method performed by the multi-axis kneading apparatus will be described below in detail with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals.
FIG. 1 is a longitudinal sectional view of a basic type multi-axis kneading apparatus 101 in this embodiment, and FIG. 2 is a cross-sectional view of the multi-axis kneading apparatus 101 of FIG.
The multi-axis kneading apparatus 101 basically includes a plurality of screw shafts 180 having so-called corrugated screws, which mesh with each other and are arranged in parallel with each other, in the same direction along a circumferential direction by a motor 190 as a driving source. The extruder is configured to be rotatable into the barrel 185, and one of the characteristic configurations is that the material discharged from the material discharge port is fed back to the vicinity of the material supply unit again. . Therefore, the multi-axis kneading apparatus 101 includes the material supply / conveyance section 110, the kneading section 120, the conveyance section 130 for discharge, and the material return section 140 as basic components.
The multi-axis kneading apparatus 101 is provided with two screw shafts 180, but may be provided with two or more screw shafts 180, for example, four shafts.

Further, on the outer surface of the barrel 185, a temperature adjusting device 150 having a plate heater or the like for performing at least one of heating and cooling of the material conveyed and kneaded in the barrel 185 can be provided.
Further, at the material discharge portion which is the tip of the barrel 185, a material to be discharged is formed into an appropriate shape, for example, a string shape or a plate shape, and a base 195 for continuously discharging the material is provided. Is preferred.
In the present embodiment, the tip of the barrel 185 provided with the base 195 is constituted by a barrel head 185-1 which is a separate member from the main body of the barrel 185. The barrel head 185-1 can be detachably fastened to the main body of the barrel 185. Note that the barrel 185 can be formed by a single member up to the tip without using a separate member such as the barrel head 185-1. When the barrel 185 is formed by one member, the withstand pressure of the barrel 185 can be increased, so that extrusion molding with a high tip pressure of the screw shaft 180 can be performed.
In the following description, the main body of the barrel 185 and the barrel head 185-1 are collectively referred to as a barrel 185.

The material supply / conveyance unit 110 includes a screw-shaped first conveyance member 111 that forms a part of the screw shaft 180, a material supply unit 112 that inputs a material to be kneaded, and a rotation of the first conveyance member 111. And a barrel 185 as a casing for fitting and loading the material supply unit 112 and arranging the material supply unit 112. The first conveying member 111 is rotated by the motor 190 so that the screw shaft 180, In the transport direction 181 along the axial direction 180 a of the one transport member 111, the materials fed from the material supply unit 112, for example, the materials A and B, are transported in the barrel 185 while being mixed.
The materials to be supplied are not limited to the two types described above, and one or more types of materials are supplied. The supplied materials are mixed and melted during the transportation. In the present embodiment, the material supply unit 112 is simply a material input port. However, a material supply device for forcibly supplying a material to the material supply / conveyance unit 110 may be provided.
FIG. 3 shows the rotation direction 182 of each screw shaft 180 as viewed from the distal end side of the screw shaft 180 near the material discharge port 186. As each screw shaft 180 rotates in the rotation direction 182, the material existing in the valley portion of each first transport member 111 is transported in the transport direction 181 while moving in the direction indicated by the arrow 181a. .

The kneading section 120 is connected to the material supply / transport section 110 along the axial direction 180a, and has a kneading member 121 and a barrel 185 as a casing for loading the kneading member 121. In the embodiment, the kneading unit 120 and the material supply / conveyance unit 110 are integrally formed. The kneading member 121 forms a part of the screw shaft 180 and is formed integrally with the first conveying member 111 of the material supply / conveying section 110 to transfer the material conveyed by the first conveying member 111. Knead.
The kneading member 121 is also called kneading, and has a configuration in which a plurality of substantially elliptical members such as leaf shapes are arranged at different arrangement angles as shown in FIG. By changing the arrangement angle, the kneading member 121 is generally of a type capable of transporting the material in the transport direction 181 when rotated in the rotation direction 182, and transporting the material in the opposite direction to the transport direction 181. There are three types, a possible type and a type without a material transport function. In the present embodiment, the types that can be transported are used, but each type described above can be used.
Further, in the multi-axis kneading apparatus 101, two kneading members 121 are arranged in parallel along the axial direction 180a, but the number of kneading members 121 is one or more according to a request for increasing or decreasing the kneading degree of the material. Can be set. For example, as shown in FIG. 8, three kneading members 121 can be provided in parallel. When a plurality of kneading members 121 are juxtaposed, only one of the above three types may be used, or a combination of the three types may be used.

  The discharge transport unit 130 is connected to the kneading unit 120 along the axial direction 180a, and serves as a casing for rotatably fitting and loading the second transport member 131 and the first transport member 111. This embodiment has a barrel 185, and in the present embodiment, the discharge transport unit 130 and the kneading unit 120 are formed integrally. The second transport member 131 is a screw-shaped member like the first transport member 111 described above, forms a part of the screw shaft 180, and is formed integrally with the kneading member 121. In the present embodiment, the second transport member 131 has the same structure as the first transport member 111 described above. The second conveying member 131 conveys the material kneaded by the kneading member 121 to the material discharge port 186 by rotating in the rotation direction 182. In addition, the discharge transport unit 130 also functions as a pressure boosting unit for transporting the material through the material return pipe 141 of the material return unit 140 described below.

Further, in this embodiment, a vent port 132 constituting a gas removing section for removing gas from the material is formed in the barrel 185 in the discharge conveying section 130, and a vacuum device 133 is provided in the vent port 132. The vent port 132 is constantly depressurized to a degree of vacuum of, for example, about 2.3 kPa (about 17 Torr). Such a reduced pressure state can be effectively achieved by providing a seal portion 175 described later. Further, the necessity of setting the vent port 132 is desirably provided in the case of processing a material whose gas, for example, air, reduces dispersibility by being mixed. For example, when kneading a material such as nanocarbon, the vent port 132 and the vacuum device 133 are indispensable configurations.
Further, in order to efficiently remove gas from the material being conveyed, the vent port 132 extends along the axial direction 180a over a length of about two threads with a thread on the second conveying member 131. Is preferred.

The material return section 140 is connected to the material discharge port 186 and supplies the material discharged from the material discharge port 186 to the material supply / transport section 110 again. It has a material return pipe 141 leading to 110. In the present embodiment, the material return pipe 141 is formed in the barrel 185 and the return block 142, and the return block 142 is attached to the barrel 185.
Further, in the present embodiment, the switching unit 143 is provided near the material discharge port 186 at a stage subsequent to the material discharge port 186. The switching section 143 is a section for supplying the material discharged from the material discharge port 186 to one of the material return pipe 141 and the base 195 of the material return section 140, and as shown in FIGS. The driving device 144 is configured to switch the flow path. In the present embodiment, the switching section 143 has a ball valve structure, and switches the flow path by rotating the flow path switching portion by the driving device 144. Note that the structure of the switching unit 143 is not limited to the above-described ball valve structure, and can employ a structure easily conceived by those skilled in the art. Normally, as shown in FIG. 5, the switching unit 143 is switched so as to connect the material discharge port 186 to the material return pipe 141, and the material is discharged at the discharge pressure of the material discharged from the material discharge port 186. It is transported and supplied to the material supply transport unit 110. It is also possible to provide the material return pipe 141 with a material transport device that forcibly transports and supplies the material discharged from the material discharge port 186 to the material supply and transport unit 110.

The connection position of the material return pipe 141 in the material supply / conveyance unit 110 is a position corresponding to the first conveyance member 111-L provided immediately before the kneading unit 120, as shown in FIG. The return position 145 is such that at least one thread of the first transport member 111-L is present before reaching. The reason why the material return pipe 141 is connected to such a return position 145 is that the return material returned through the material return pipe 141 can be transported to the kneading unit 120 by rotation of the first transport member 111-L. . That is, when the material return pipe 141 is connected immediately before the kneading unit 120, the thread of the first conveying member 111-L does not exist, and the return material is difficult to supply or cannot be supplied to the kneading unit 120. Because.
Note that the connection position of the material return pipe 141 in the material supply / conveyance unit 110 is most preferably the return position 145, but a position between the position where the screw thread exists and the material supply unit 112 should be selected. You can also.

  In addition, for example, as shown in FIG. 8, when the number of the kneading members 121 changes, the return position 145 of the material return pipe 141 needs to be changed. In order to cope with such a position change, for example, each return block 142 in which a material return pipe 141 having a length corresponding to each return position 145 is formed, and the return block 142 is formed into a barrel. It is preferable to make a contrivance such as a detachable structure for the 185 or a structure in which the material return pipe 141 can expand and contract.

As an example of the dimensions of each part in the multi-axis kneading apparatus 101 in the present embodiment, the diameter of the screw-shaped first conveying member 111 and the second conveying member 131 is 15 mm, and the material supply / conveying section along the axial direction 180a is provided. The length of 110 is about 80 mm, the length of the discharge conveyance section 130 is about 40 mm, and the length of the kneading section 120 is about 30 mm.
Further, as described above, the multi-axis kneading apparatus 101 is not only an apparatus for simply kneading the materials, but also can extrude the kneaded materials to the outside of the apparatus, and circulates the materials in the apparatus system for the material kneading. It can be carried out. Therefore, the multi-screw kneading apparatus 101 of this embodiment can also be called an extruder with a multi-screw kneading unit or a material circulation type extruder with a multi-screw kneading unit.

The multi-axis kneading apparatus 101 having the above-described configuration may have the following modified configurations.
As in the multi-axis kneading apparatus 102 shown in FIG. 7, the material supply / conveyance unit 110 includes a gas that is located behind the material supply unit 112 and constitutes a gas supply unit for supplying gas to the conveyed material. A supply port 171 and a gas supply device 172 for supplying gas to the gas supply port 171 can be further provided. As an example of the supplied gas, there is a nitrogen gas or the like for preventing oxidation of the conveyed material.
Further, the discharge transport unit 130 is located behind the vent port 132, and forms a liquid supply unit 173 that supplies a liquid to the material to be discharged, and supplies liquid to the liquid supply port 173. An additional liquid supply device 174 can be provided. An example of a liquid to be supplied is a plasticizer or a lubricant. By providing such a liquid supply function, by adding a liquid to the material, the workability of the material can be improved or the fluidity can be improved.
In addition, the liquid supply port 173 and the liquid supply device 174 can be provided at an appropriate place behind the material supply unit 112 in the material supply / conveyance unit 110.
The other configuration of the multi-axis kneading apparatus 102 is not different from the configuration of the above-described multi-axis kneading apparatus 101.

  Further, a configuration in which the number of kneading members 121 provided in the kneading unit 120 is three, or three or more or one as in the multi-axis kneading apparatus 103 shown in FIG. . The other configuration of the multi-axis kneading apparatus 103 is not different from the configuration of the multi-axis kneading apparatus 101 described above.

  Furthermore, as in the multi-axis kneading device 104 shown in FIG. 9, a seal portion 175 can be provided between the kneading portion 120 and the discharge conveying portion 130. The seal portion 175 has a screw-shaped seal member 176 having a reverse screw structure with respect to the second transport member 131 of the discharge transport portion 130, and a casing as a casing for rotatably fitting and loading the seal member 176. With a barrel. The seal member 176 becomes a part of the screw shaft 180, and is formed integrally with the kneading member 121 and the second conveying member 131. In the multi-axis kneading apparatus 104, the length of the seal member 176 in the axial direction 180a is equal to the length of a half screw thread, but the length of the seal member 176 is not limited to this.

By providing such a seal portion 175, the material movement from the kneading unit 120 to the discharge conveyance unit 130 is suppressed, and on the other hand, the material is supplied from the material supply conveyance unit 110 to the kneading unit 120. The material pressure in the kneading section 120 can be improved. That is, when the vacuum decompression venting is performed from the vent port 132 without providing the seal portion 175, the material filling rate in the vent port 132, the kneading unit 120, and the material supply / conveyance unit 110 becomes low due to poor sealing performance. Depending on the case, the material may be sucked from the vent port 132. On the other hand, by providing the seal portion 175, even when the vacuum depressurizing vent is performed from the vent port 132, the sealing property is generated in the seal portion 175 because the material pressure in the kneading section 120 is high, and the suction force at the vent port 132. Can be prevented from acting on the material supply / conveyance unit 110. Therefore, the degree of vacuum at the vent port 132 can be maintained. When a small amount of material is charged, the filling volume in the apparatus is small, and therefore, in many cases, the vacuum cannot be maintained only by the kneading member 121. Therefore, in a multi-axis kneading apparatus for processing a small amount of material, the provision of the seal portion 175 is an effective means for maintaining a vacuum.
Further, by providing the seal portion 175, the material supply to the kneading unit 120 is improved, so that the kneading properties of the material in the kneading unit 120 can be improved.
The other configuration of the multi-axis kneading apparatus 104 is not different from the configuration of the multi-axis kneading apparatus 101 described above.

  It is also possible to produce a multi-axis kneading apparatus having a configuration obtained by appropriately combining the configurations of the various multi-axis kneading apparatuses 101 to 104 described above.

The operation of the multi-axis kneading apparatus configured as described above, that is, the material kneading method will be described below. The multi-axis kneading apparatus 101 will be described as an example.
By operating the motor 190 and rotating the first conveying member 111, the kneading member 121, and the second conveying member 131 at a predetermined number of rotations in the rotation direction 182, for example, the material A and the material B are supplied to the material supply unit 112. Input. As an example of the material, a total of 5 g of 3 g of the resin material and 2 g of the filler material are charged. Due to the rotation, the material is transported in the transport direction 181 by the first transport member 111 while moving along the arrow 181a. The materials are mixed by the conveyance, and may be melted by heating or cooling by the temperature control device 150. Then, the material is supplied to the kneading unit 120 by the above-described conveyance.
In the kneading section 120, the materials are kneaded by the kneading member 121, and after kneading, the material is supplied to the discharge conveying section 130 in the next stage. In the discharge transport section 130, the kneaded material is transported in the transport direction 181 by the second transport member 131. Then, the kneaded material is supplied to the material return pipe 141 through the material discharge port 186 and the switching unit 143 at the discharged pressure, and is supplied again to the material supply / transport unit 110 through the material return pipe 141. You.

The material is repeatedly supplied from the material discharge port 186 through the material return pipe 141 to the material supply / conveyance unit 110 until the supplied material can be evaluated for the kneading property and the like.
When it is determined that the evaluation is possible, the drive unit 144 is operated to switch the flow path of the switching unit 143 from the material return pipe 141 side to the base 195 side. Then, the sufficiently kneaded material is formed into a desired shape such as a cylindrical shape or a flat shape by a base 195 and discharged.

As described above, according to the multiaxial kneading apparatus of the present embodiment, the material can be repeatedly kneaded particularly in the kneading section 120, and the material can be mixed in the material supply / conveyance section 110 and the discharge / conveyance section 130 along the arrow 181a. Can be transported while being moved, and the material is not unevenly distributed or left in a certain place. Further, in the movement along the arrow 181a, the material is transported while being mixed, so that air bubbles which may be mixed in the material can be sufficiently removed, and the material kneading property can be improved as compared with the conventional apparatus. Can be improved. Therefore, according to the multi-axis kneading apparatus of the present embodiment, the materials can be kneaded efficiently and sufficiently as compared with the conventional apparatus.
Further, by providing the switching unit 143, the kneaded material can be taken out of the apparatus, and further, the material can be formed and taken out by passing through the base 195.
In addition, according to the multi-axis kneading apparatus of the present embodiment, since the length of the apparatus can be prevented by having the material return section 140, the kneading operation of the material having the material conveying function can be performed with a small amount of material, for example, 5 times. The physical properties of the material, for example, the kneading property, can be evaluated using the material in an amount of about gram. Further, by having the material return section 140, the degree of kneading of the material can be adjusted at an arbitrary number of times or time even if the material is insufficiently melted and kneaded in one transfer and kneading. Therefore, the problems of overload and kneading / dispersion problems that occur in the conventional apparatus do not occur in the multi-axis kneading apparatus of the present embodiment.
Further, by having the material return portion 140, since the kneaded material does not need to be once taken out of the apparatus, there is little effect on the heat history such as cooling, solidification, reheating and melting, acting on the material, and The physical property evaluation can be performed more accurately.

  Further, in the present embodiment, the distal end portion of the barrel 185 is configured to be detachable as the barrel head portion 185-1, so that the barrel 185 is not divided into upper and lower portions, and the driving portion of the motor 190 is attached to the barrel 185. In this state, the screw shaft 180 can be pulled out from the front. Therefore, for example, the inside of the barrel can be easily cleaned. Further, as described later, the material is sampled from a sampling unit 146 provided in the material return unit 140-1 or the like, and for example, replacement of the screw shaft 180, extension of the barrel, etc., based on the physical properties of the sampled material. , These operations can be easily performed.

  Although the above-described multiaxial kneading apparatuses 101 to 104 have been described as being suitable for conveying and kneading a small amount of material, it is needless to say that the material is returned by scaling up each part such as the diameter of the first conveying member 111. A large-sized multi-axis kneading apparatus having the portion 140 may be manufactured. According to the large-sized multi-screw kneading apparatus, the extruder has a small value of L / D, which is a ratio of a screw outer circumference moving distance when the screw makes one rotation and a groove depth of the screw, and has a long length. It is also possible to use the extruder as a substitute for the shafted extruder.

  In the above description, an example in which a filler material is simultaneously added to a resin material has been described.However, only the resin material is added first, and after the resin material is melted, or after a certain period of time, the filler material is added. You can also. For example, when processing a fiber-based material such as glass fiber, the multiaxial kneading apparatuses 101 to 104 can easily shorten the fiber length. Therefore, it is better to knead the material after melting than to knead the material before melting. Can be maintained for a long time.

  The above-described material return unit 140 has a function of simply returning the material to the material supply / conveyance unit 110. For example, the material return speed, the return pressure, the return amount, and the temperature of the material in the material return pipe 141 are determined. It is difficult to measure a physical quantity, and it is difficult to grasp, for example, a kneading time in the material supply / conveyance unit 110, the kneading unit 120, and the discharging / conveying unit 130. Therefore, as a modified example of the material return section 140, the following material return section can be adopted.

  As an example, a material return portion 140-1 shown in FIG. 10 can be provided in place of the material return portion 140. The material return section 140-1 has a sampling section 146. Other configurations of the material return section 140-1 are the same as those of the material return section 140. The sampling section 146 is provided in the material return pipe 141 immediately before the return position 145 in the material transport direction, and enables sampling of the material returned to the material supply transport section 110 through the material return pipe 141 from the material return pipe 141. This is the part to do. Like the switching unit 143, the sampling unit 146 has a ball valve structure in this embodiment and has a flow path switching part 1461 that switches the conveyance of the material to the return position 145 side or the sampling port 1463 side; And a driving device 1462 for rotating the portion 1461. In order to sample the circulating material in the same state as possible when the material is circulated to the material supply / conveyance unit 110 using the material return unit 140-1, the return position from the center of the flow path switching unit 1461 is sampled. The sampling unit 146 is configured such that a path 1464 to 145 and a path 1465 from the center of the flow path switching portion 1461 to the sampling port 1463 have the same condition. For example, the path 1464 and the path 1465 have the same length, path cross-sectional shape, route shape, and the like.

  By providing such a material return portion 140-1, even when the material is circulated through the material return portion 140-1, the drive device 1462 rotates the flow path switching portion 1461 according to the situation. By switching the flow path from the return position 145 to the sampling port 1463, the circulating material can be taken out of the system. By the take-out operation, the physical quantity of the circulating material, for example, the amount of material discharged per unit time in the material return pipe 141, the return conveyance speed, the pressure, the temperature, and the like can be measured. In addition, by making at least the cross section of the sampling port 1463 circular, the above-mentioned material can be taken out in a string form from the sampling port 1463, and the taken-out material can be cut into a certain length to be pelletized. Ideal for secondary processing.

As another example, a material return portion 140-2 shown in FIG. 11 can be provided in place of the material return portion 140. In the present embodiment, the material return section 140-2 has the configuration of the material return section 140-1, and has a measuring device 147 for measuring the physical quantity of the circulating material. In the present embodiment, as the measuring device 147, two pressure detectors 147-1 and 147-2 are provided at a predetermined measurement distance ML in the material return pipe 141.
With the conventional extruder, the viscosity of the material could not be confirmed during kneading, but the material was circulated by providing the pressure detectors 147-1 and 147-2 in the material return section 140-2 as described above. It is possible to determine the change over time of the material being used, that is, the change in viscosity of the material due to kneading, by measuring the pressure loss between two points. Therefore, by obtaining the relationship between the holding time and the change in viscosity, it is possible to infer the appropriate L / D when continuous molding is performed in an actual multi-screw extruder.
In addition, a thermometer or a glass window for visualizing the flow state of the material can be attached as the measuring device 147.

When the kneading of the material is completed at the specified number of circulations, the material is discharged from the base 195 to the outside by switching the flow path to the base 195 by the switching unit 143 as described above. On the other hand, by providing the above-described material return section 140 and the like, when the switching section 143 switches the flow path to the base 195 side, the material existing in the material return pipe 141 in the material return section 140 and the like. Is stopped, and the material stays in the material return pipe 141. The accumulated material needs to be removed by washing or the like. However, as another example of the material returning unit 140, the material returning unit 140-3 shown in FIG. is there.
That is, the material return part 140-3 is provided in place of the material return part 140, has the configuration of the material return part 140-1, and is a test piece of the material with the material retained in the material return pipe 141. Has a mold part 148 for producing a test piece. Conventionally, a test piece is formed by an injection molding machine after forming a pellet by an extruder. However, by providing a material return portion 140-3, a test piece can be manufactured without going through the conventional process described above. Becomes possible. The test piece preparation mold portion 148 has a shape capable of forming a No. 1-4 test piece for material testing as specified in JIS (Japanese Industrial Standards) K 7113 (2003 edition). FIG. 12 shows a test piece preparation mold part 148 for forming a test piece corresponding to a No. 2 test piece, and a test piece for forming a test piece corresponding to a No. 4 test piece in FIG. The fabrication mold part 148 is shown.

By providing the test piece preparation mold part 148, when the circulation of the material for kneading is completed and the switching part 143 switches the flow path to the base 195 side, the material return part 140-3 is removed from the barrel 185. Upon cooling, the remaining material solidifies. By this operation, the test piece can be automatically formed and manufactured by the test piece manufacturing mold part 148. Therefore, it is efficient and material loss can be reduced. Although not shown in FIGS. 12 and 13, the test piece manufactured by the test piece manufacturing mold part 148 is taken out from the material return part 140-3. Has an opening / closing mechanism for taking out a test piece.
Further, in order to produce various test pieces, a plurality of material return portions 140-3 corresponding to the test piece producing mold portions 148 of each shape may be prepared and replaced with the barrel 185.
Further, the test piece need not be prepared after the circulation of the material for kneading is completed, and the test piece can be prepared in the test piece preparation mold part 148 according to the situation even during kneading. In this case, it is necessary to replace the material return section 140-3.
Further, when the test piece preparation mold part 148 is provided, the amount of the material to be charged into the first transport member 111 is set to be smaller than that of the other material return parts 140, 140-1, and 140-2. We need to do more for the equivalent.

Further, as another example, a material return portion 140-4 shown in FIG. 13 can be provided in place of the material return portion 140. The material return section 140-4 combines the configuration of the material return section 140-2 shown in FIG. 11 and the configuration of the material return section 140-3 shown in FIG. And a unit 148.
According to such a material return section 140-4, both the effect of the configuration of the material return section 140-2 and the effect of the configuration of the material return section 140-3 shown in FIG. 12 can be obtained. In particular, in the material return portion 140-4 shown in FIG. 13, since the shape of the test piece producing mold portion 148 is a shape corresponding to the above-mentioned No. 4 type test piece, the No. 2 type test as shown in FIG. The influence of the pressure loss of the material on the test piece forming mold part 148 is smaller than that of the test piece. Therefore, the pressure detectors 147-1 and 147-2 can be provided in addition to the test piece preparation mold part 148.

  The above-described material return sections 140-2, 140-3, and 140-4 have a structure in which the sampling section 146 of the material return section 140-1 is provided side by side. However, the present invention is not limited to this configuration. A configuration without the 146 may be employed.

  INDUSTRIAL APPLICABILITY The present invention is applicable to a multi-axis kneading apparatus that has a plurality of screws and a material kneading member to knead a material and extrude the material.

It is a longitudinal section of a multiaxial kneading device which is an embodiment of the present invention. It is a cross-sectional view of the multi-axis kneading device shown in FIG. It is a figure which shows the screw shaft provided in the multi-axis kneading apparatus shown in FIG. 1, and its rotation direction. It is a figure which shows the shape and rotation direction of the member for kneading provided in the multiaxial kneading apparatus shown in FIG. FIG. 2 is a diagram for explaining an operation of a switching unit provided in the multi-axis kneading device shown in FIG. 1. FIG. 2 is a diagram for explaining an operation of a switching unit provided in the multi-axis kneading device shown in FIG. 1. It is a figure which shows the modification of the multi-axis kneading apparatus shown in FIG. It is a figure which shows another modification of the multi-axis kneading apparatus shown in FIG. It is a figure which shows another modification of the multi-axis kneading apparatus shown in FIG. FIG. 4 is a view showing a modification of the material return section shown in FIG. 1. It is a figure which shows the other modification of the material return part shown in FIG. It is a figure which shows another modification of the material return part shown in FIG. It is a figure which shows another modification of the material return part shown in FIG.

Explanation of reference numerals

101 to 104: multi-axis kneading device,
110: material supply / transport section, 111: first transport member, 112: material supply section,
120: kneading section, 121: kneading member, 130: discharge conveying section,
131: second conveying member, 140: material return section, 143: switching section,
146: Sampling unit, 147: Measuring device, 148: Mold part for preparing test piece,
150 temperature control device, 173 liquid supply port, 174 liquid supply device
175: seal portion, 176: seal member, 180a: axial direction,
181: conveyance direction, 186: material discharge port, 195: base.

Claims (13)

A plurality of first conveying members (111) meshed with each other and arranged in parallel with each other in a screw shape, and a material supply unit (112) of a material to be kneaded, and the first conveying member rotates to rotate the first conveying member. A material supply and transport unit (110) configured to transport the material in a transport direction (181) along the axial direction (180a) of the one transport member;
A kneading section (120) having a kneading member (121) connected to the material supply / conveyance section along the axial direction and kneading the material conveyed by the material supply / conveyance section;
It has a plurality of second conveying members (131) that are connected to the kneading section along the axial direction, mesh with each other in a screw shape, and are arranged in parallel with each other. A discharge conveyance unit (130) that conveys the material to the material discharge port (186) by rotation of the second conveyance member;
A material return section (140) connected to the material discharge port and supplying the material discharged from the material discharge port to the material supply / conveyance section again;
A multi-axis kneading device comprising:   The material return section has a material return pipe (141) for supplying the material discharged from the material discharge port to the material supply / transport section again, and the material return pipe is installed immediately before the kneading section. 2. The multi-axis kneading apparatus according to claim 1, wherein the multi-axis kneading apparatus is connected to the material supply / conveying section at a return position (145) which is at least one or more threads apart from the kneading section in the thread of the first conveying member.   The material return section further includes a sampling section (146) provided immediately before the return position in the material return pipe and sampling the material returned to the material supply / transport section through the material return pipe from the material return pipe. The multi-shaft kneading apparatus according to claim 2.   The multi-material as claimed in claim 2, wherein the material return unit further includes a measuring device provided in the material return tube and measuring a physical quantity of the material returned to the material supply / conveyance unit in the material return tube. Shaft kneading device.   The said material return part further has the test piece preparation type | mold part (148) which produces the test piece of the said material with the said material provided in the said material return pipe and staying in the said material return pipe, The Claims 2-4. The multi-axis kneading apparatus according to any one of the above.   A switching unit (143) provided at the material outlet, and further configured to supply a material discharged from the material outlet to one of the material return unit and a die (195) for molding the material. The multi-shaft kneading device according to any one of 1 to 5.   The multi-axis kneading apparatus according to any one of claims 1 to 6, further comprising a temperature control device (150) that performs at least one of heating and cooling of the material during transport and kneading of the material.   The multi-axis kneading apparatus according to any one of claims 1 to 7, further comprising a gas removing unit (132, 133) provided in the discharge transport unit and configured to remove gas from the material.   9. The multi-function printer according to claim 1, further comprising a liquid supply unit (173, 174) provided on at least one of the material supply / conveyance unit and the discharge conveyance unit, and configured to supply a liquid to the material. Shaft kneading device.   The multiaxial kneading apparatus according to any one of claims 1 to 9, further comprising a gas supply unit (171, 172) provided in the material supply / conveyance unit and configured to supply gas to the material.   The seal part (175) which has the screw-shaped seal member (176) which has a reverse screw structure with respect to the said 2nd conveyance member between the said kneading part and the said discharge conveyance part, It further provided. The multi-shaft kneading device according to any one of 1 to 10. The supplied materials (A, B) are transported by the screw-shaped first transport member (111) in the transport direction (181) along the axial direction (180a) of the first transport member,
Kneading the above-mentioned materials that have been conveyed,
The kneaded material is transported to the material discharge port (186) by the screw-shaped second transporting member (131),
The material discharged from the material discharge port is returned to the first conveying member again through the material return pipe (141) to repeatedly knead the material.
A material kneading method characterized by the above-mentioned. The material is returned by the material return pipe to a return position (145) which is at least one or more ridges apart from the material kneading operation in the threads of the first transport member provided immediately before the material kneading operation. The method for kneading materials according to claim 12.

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