Extrusion device and method for kneading resin raw material

Abstract

Provided are an extrusion device and a method for kneading a resin raw material, in which energy discharged and discarded by a cooling mechanism provided in the extrusion device is utilized in the same device, thereby improving the utilization efficiency of the energy. An extrusion device (10) is provided with: a cylinder (12) having an upstream region (12UA) and a downstream region (12DA); a resin raw material supply unit (11) provided on the upstream region (12UA) side of the cylinder (12); a screw disposed in the cylinder (12) and used for conveying and kneading the resin raw material; and a resin raw material discharge section (15) provided on the downstream region (12DA) side of the cylinder (12). The resin raw material discharge section (15) is provided with: a heating mechanism (14) provided on the upstream region (12UA) of the cylinder for heating the resin raw material; a cooling mechanism (16) provided in a downstream region (12DA) of the cylinder for cooling the cylinder (12); and a pipe (17) that is disposed so as to connect the upstream region (12UA) and the downstream region (12DA) of the cylinder (12) and that is connected to the cooling mechanism (16).

Description

Technical Field

[0001] The present invention relates to an extrusion device and a mixing method for resin raw materials. Background Art

[0002] Resin products made from resin compositions are currently used in a wide range of fields and in enormous quantities. To produce these resin products, extruders are used to produce resin raw materials such as resin pellets. Within the cylinder of the extruder, a heating mechanism is installed to heat and melt the resin raw material within the cylinder.

[0003] On the other hand, due to shear heat generated by the rotation of the screw when the resin raw material is conveyed and kneaded, there is an area in the cylinder where excessive heat is generated, and therefore a cooling mechanism is required.

[0004] For example, refer to Japanese Patent Application Laid-Open No. 6-23824 (Patent Document 1) and the like.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 6-23824 Summary of the Invention

[0008] An improvement in energy efficiency is sought in an extrusion device having a heating mechanism and a cooling mechanism.

[0009] Other objects and new features will become apparent from the description of this specification and the accompanying drawings.

[0010] The extrusion device disclosed in the present application includes: a cylinder having an upstream area and a downstream area; a supply portion for a resin raw material provided on the upstream area side of the cylinder; a screw arranged in the cylinder for conveying and mixing the resin raw material; and a discharge portion for the resin raw material provided on the downstream area side of the cylinder.

[0011] Moreover, the extrusion device has: a heating mechanism for heating the resin raw material provided in the upstream area of the cylinder; a cooling mechanism for cooling the cylinder provided in the downstream area of the cylinder; and a piping configured to connect the upstream area and the downstream area of the cylinder and connected to the cooling mechanism.

[0012] The kneading method of the resin raw material disclosed in the present application has the following steps: (a) a step of heating and melting the resin raw material supplied to a cylinder having an upstream region and a downstream region while conveying it in the cylinder by a screw and heating it by a heating mechanism provided in the upstream region; (b) a step of cooling the cylinder by a cooling mechanism provided in the downstream region of the cylinder while kneading the resin raw material after the step (a); (c) a step of discharging the kneaded product of the resin raw material from a discharge portion provided at the front end of the cylinder after the step (b); and (d) a step of causing a fluid to flow from the downstream region to the upstream region after the step (b).

[0013] Effect of the Invention

[0014] According to the extrusion device and the kneading method of the resin raw material disclosed in the present application, an extrusion device and a kneading method of the resin raw material with improved energy utilization efficiency can be provided. Description of the Drawings

[0015] Figure 1 It is a diagram showing a schematic structure of an extrusion device according to an embodiment.

[0016] Figure 2 It is to explain in Figure 1 a diagram showing an example of the internal structure of a cylinder used in the extrusion device.

[0017] Figure 3 It is a diagram showing an example of the shape of a screw used in the extrusion device in Figure 1

[0018] Figure 4 It is a diagram showing another example of the shape of a screw used in the extrusion device in Figure 1

[0019] Figure 5 It is a diagram showing Figure 1 another embodiment of the extrusion device.

[0020] Figure 6 It is a diagram showing Figure 1 a modified example of the extrusion device.

[0021] Figure 7 It is a diagram showing Figure 1 another modified example of the extrusion device.

[0022] Figure 8 It is a diagram showing a schematic structure of the extrusion device used in the embodiment. Detailed Description of the Invention

[0023] ​​Hereinafter, embodiments will be described in detail with reference to the drawings. It should be noted that in all the drawings used to illustrate the embodiments, components having the same function are denoted by the same reference numerals, and redundant descriptions thereof are omitted. In addition, in the following embodiments, the description of the same or similar parts is not repeated in principle unless particularly necessary.

[0024] <Embodiment 1>

[0025] While referring to Figure 1 while explaining the overall structure of the extrusion device of the present embodiment and the kneading method of the resin raw material using the extrusion device.

[0026] [Extrusion Device]

[0027] Figure 1 is an explanatory diagram showing a schematic structure of the extrusion device 10 of Embodiment 1. The extrusion device 10 is a device used to soften, melt the resin raw material by heating it inside, and extrude the molten resin from the discharge part provided at its front end to obtain a molding resin material in which the resin raw material is sufficiently kneaded.

[0028] The extrusion device 10 includes: a resin raw material supply unit 11; a cylinder 12 having an upstream region 12UA and a downstream region 12DA and provided with a screw inside; a rotational drive mechanism 13 for driving the screw in the cylinder 12; a heating mechanism 14 provided in the upstream region 12UA; a discharge part 15; and a cooling mechanism 16 provided in the downstream region 12DA.

[0029] In addition, the extrusion device 10 includes: a pipe 17 connecting the upstream region 12UA and the downstream region 12DA and connected to the cooling mechanism 16; an auxiliary heating mechanism 18 provided in the upstream region 12UA and connected to the pipe 17; and a vent part 19 capable of discharging the gas generated in the cylinder.

[0030] The resin raw material supply unit 11 is a component that supplies the resin raw material as a molding material to the cylinder 12. In the present embodiment, for example, a thermoplastic resin is supplied as the resin raw material. As the thermoplastic resin to be supplied, various forms of thermoplastic resins such as granules, powders, and flakes are used. For example, they are input from above through a feeder or the like into the resin raw material supply unit 11 and supplied into the cylinder 12. As the resin raw material supply unit 11, for example, a hopper or the like may be provided by connecting it to the upper surface opening of the cylinder 12.

[0031] The cylinder block 12 is also referred to as a cylinder barrel, and a space for transporting resin raw materials is formed inside it. A screw for transporting and kneading resin raw materials is provided in this space. The cylinder block 12 is constituted by connecting, for example, a plurality of cylinder blocks, and a space capable of transporting thermoplastic resin is provided in each cylinder block. This space is formed in such a way that it becomes a single space penetrating the inside of the cylinder block 12 when the plurality of cylinder blocks are connected.

[0032] Figure 2 It is a diagram showing the internal structure of the cylinder block 12. A screw 12a is arranged in the space formed by connecting a plurality of cylinder blocks, and the screw 12a is connected to a rotational drive mechanism 13. In addition, in the Figure 2 cylinder block 12, an upper surface opening 12b connected to the resin raw material supply unit 11 and an upper surface opening 12c connected to the ventilation unit 19 are also shown.

[0033] The rotational drive mechanism 13 is a device for rotating the screw 12a provided in the cylinder block 12. By using the screw 12a rotated by the rotational drive mechanism 13, it is possible to transport and knead resin raw materials in the cylinder block 12.

[0034] In addition, the extrusion device 10 can be a twin-screw extruder having two screws provided in the cylinder block 12, or a single-screw extruder having one screw. In the case of a twin-screw extruder, the two screws are arranged and rotated parallel to each other. The two screws can be arranged to mesh with each other or not to mesh.

[0035] Based on the flow direction of the raw material resin, the cylinder block 12 has an upstream region 12UA and a downstream region 12DA. That is, the raw material resin is supplied from the resin raw material supply unit 11 into the cylinder block 12, transported in the cylinder block 12, and discharged to the outside of the cylinder block 12 from the discharge unit 15. Therefore, the side of the resin raw material supply unit 11 in the cylinder block 12 becomes the upstream region 12UA, and the side of the discharge unit 15 becomes the downstream region 12DA. At this time, the boundary between the upstream region 12UA and the downstream region 12DA can be set arbitrarily. For example, the region mainly for stepwise heating the temperature of the cylinder block 12 and raising the cylinder temperature can be set as the upstream region 12UA, and the region for maintaining the cylinder temperature at the same level after the resin material is sufficiently heated and melted can be set as the downstream region 12DA.

[0036] The upstream region 12UA is a region for stepwise heating its temperature by applying heat energy to the cylinder block 12 from the outside as described above, and is provided with a heating mechanism 14 for adjusting the temperature of the cylinder block 12. As this heating mechanism 14, as long as it can heat the cylinder block 12, a known heating mechanism can be used, and there is no particular limitation. As the heat source constituting the heating mechanism 14, for example, an electric heater, hot oil, steam, etc. can be cited.

[0037] The resin raw material supplied from the resin raw material supply unit 11 is conveyed in the cylinder body 12 from the resin raw material supply unit 11 toward the discharge unit 15 side. However, at this time, it is gradually heated and melted in the upstream region 12UA to become a melt. The melt thus obtained can be easily conveyed in the cylinder body 12 and further conveyed toward the downstream region 12DA side while being heated. In this upstream region 12UA, the resin raw material can be heated to the molding temperature.

[0038] The downstream region 12DA is a region where heat energy is externally applied to the cylinder body 12 to maintain its temperature as described above. In this region, a heating mechanism 14 for adjusting the temperature of the cylinder body 12 is also provided. As this heating mechanism 14, the same heating mechanism as the heating mechanism described above can be used.

[0039] The resin raw material heated and melted in the upstream region 12UA can be conveyed in the cylinder body 12 while maintaining its molten state in the downstream region 12DA, and conveyed to the discharge unit 15 while maintaining its temperature through the heating mechanism 14 provided outside the cylinder body 12.

[0040] That is, the heating mechanism 14 can be provided at an arbitrary position in the range from the upstream region 12UA to the downstream region 12DA of the cylinder body 12 in such a manner that the cylinder body 12 becomes a specified heating state. In order to efficiently control its temperature, it is preferable to provide the heating mechanism 14 on most of the cylinder body 12.

[0041] In addition, in Figure 1 it is described that the heating mechanism 14 is provided on a part (upper part) of the cylinder body 12, but this is shown schematically. In order to be able to uniformly heat the cylinder body 12 provided with the heating mechanism 14, it is preferably arranged in a manner surrounding the outer periphery of the cylinder body 12.

[0042] The discharge unit 15 is a component provided on the downstream region 12DA side (front end) of the cylinder body 12 and discharges the resin raw material conveyed in the cylinder body 12 to the outside. This discharge unit 15 has, for example, a hole for extrusion molding for extrusion molding, and the shape of the molded product is determined according to the shape of this hole. At this time, the shape of the hole can be set to various shapes as long as it is selected in such a way that the resin raw material can be molded into the desired shape. For example, when molding into a strand shape, a plurality of circular holes are provided, and when molding into a sheet shape, a slit-shaped hole is provided.

[0043] And, in the present embodiment, a cooling mechanism 16 for cooling the cylinder body 12 is provided in the downstream region 12DA of the cylinder body 12. This cooling mechanism 16 can cool the cylinder body 12 to adjust its temperature.

[0044] The cooling mechanism 16 is not particularly limited as long as it serves the above-mentioned functions, and preferably, it is a mechanism that can cool the cylinder block 12 through heat exchange using a cooling fluid (refrigerant). As such a cooling mechanism 16, for example, a cooling water jacket disposed outside the cylinder block 12, a structure in which a flow path through which a cooling fluid (refrigerant) can flow is provided inside the cylinder wall constituting the cylinder block 12 and the fluid is supplied to this flow path, etc. can be cited.

[0045] When the cylinder block 12 is overheated and the temperature of the cylinder block 12 is higher than the set temperature, the cooling mechanism 16 serves to lower the temperature so as to approach the set temperature. As described above, in the extrusion device 10, when the resin is conveyed and kneaded by the screw 12a, shear energy is generated, and thus, there is a case where the temperature becomes higher than expected due to the heat energy from the heating mechanism 14 and this shear energy.

[0046] The cooling mechanism 16 is a mechanism for lowering the temperature of the cylinder block 12 so as to approach the set temperature when the cylinder block 12 becomes hot like this. That is, the cooling mechanism 16 is provided at a position where there is a concern that the temperature of the resin raw material is higher than the set temperature of the cylinder block 12.

[0047] In the present embodiment, the temperature of the cylinder block 12 can be lowered by performing heat exchange using a cooling fluid (refrigerant) by means of the cooling mechanism 16. For the cooling mechanism 16 illustrated here, a flow path through which a cooling fluid (refrigerant) capable of heat exchange with the cylinder block 12 flows is provided inside, and it has a fluid supply port 16a for supplying the fluid (refrigerant) to this flow path and a fluid discharge port 16b for discharging the fluid (refrigerant) that has flowed through the flow path and has been heated.

[0048] In Figure 1 an example is given of the case where the cooling mechanism 16 is provided on a part (lower part) of the cylinder block 12 in the downstream region 12DA. However, similar to the content described regarding the above-mentioned heating mechanism 14, in order to be able to cool the cylinder block 12 provided with the cooling mechanism 16 uniformly, it is preferably arranged so as to surround the outer periphery of the cylinder block 12. In addition, the cooling mechanism 16 may be configured such that a plurality of cooling mechanisms are provided and the cooling fluid (refrigerant) can flow through them separately.

[0049] In addition, in the part of the cylinder block 12 where the cooling mechanism 16 is provided, in addition to the cooling mechanism 16, a heating mechanism 14 is also provided. Before the cylinder block 12 is overheated, cooling based on the cooling mechanism 16 is not performed, but heating is performed by the heating mechanism 14 so as to achieve the desired cylinder temperature. The cooling mechanism 16 operates to lower the cylinder temperature when the cylinder block 12 is overheated.

[0050] Further, in the present embodiment, it is characterized in that a pipe 17 is provided which is arranged to connect the upstream region 12UA and the downstream region 12DA. The pipe 17 is connected to a cooling mechanism 16 provided in the downstream region 12DA, and can transport the fluid (refrigerant) heated by heat exchange in the cooling mechanism 16 from the downstream region 12DA to the upstream region 12UA.

[0051] The heated fluid (refrigerant) transported by the pipe 17 is used to heat the cylinder block 12 by heat exchange in the upstream region 12UA. By adopting such a structure, the heated fluid (refrigerant) can be utilized, that is, in addition to the energy from the heating mechanism 14, the heated fluid (refrigerant) transported by the pipe 17 can also be used to heat the cylinder block 12 in the upstream region 12UA.

[0052] At this time, in order to use the heated fluid to heat the cylinder block 12, the pipe 17 is arranged to be able to transport the fluid (refrigerant) to a part of the cylinder block 12 in the upstream region 12UA, where the temperature of the cylinder block is lower than the temperature of the heated fluid (refrigerant). By adopting such a structure, in addition to the heating mechanism 14, the heated fluid (refrigerant) transported by the pipe 17 can also be used to heat the cylinder block 12.

[0053] Specifically, in the upstream region 12UA of the cylinder block 12, an auxiliary heating mechanism 18 for assisting in heating the cylinder block 12 is provided, and the auxiliary heating mechanism 18 is connected to the pipe 17, and the heated fluid (refrigerant) can be supplied.

[0054] The auxiliary heating mechanism 18 is not particularly limited as long as it can perform the above functions. Preferably, it is a mechanism that can assist in heating the cylinder block 12 through heat exchange using the heated fluid (refrigerant). As the auxiliary heating mechanism 18, for example, an auxiliary heating water jacket arranged outside the cylinder block 12, a structure in which a flow path allowing the heated fluid (refrigerant) to flow is provided inside the cylinder wall constituting the cylinder block 12 and the fluid (refrigerant) is supplied to the flow path, etc. can be cited.

[0055] The auxiliary heating mechanism 18 is a mechanism for heating the temperature of the cylinder block 12 in the upstream region 12UA where the cylinder block 12 is heated to increase its temperature. That is, the auxiliary heating mechanism 18 is provided at a position where it heats the cylinder block 12 together with the heating mechanism 14.

[0056] In the present embodiment, the temperature of the cylinder block 12 can be raised by performing heat exchange using a heated fluid (refrigerant) with the aid of the auxiliary heating mechanism 18. In the illustrated auxiliary heating mechanism 18, a flow path through which the heated fluid (refrigerant) capable of exchanging heat with the cylinder block 12 flows is provided inside, and it has a heating fluid inlet 18a for supplying the fluid (refrigerant) into the flow path and a heating fluid outlet 18b for discharging the fluid (refrigerant) that flows in the flow path and has its temperature reduced. The heating fluid inlet 18a is connected to the pipe 17 so that the fluid can flow as described above.

[0057] In Figure 1 it is illustrated that the auxiliary heating mechanism 18 is provided on a part (lower part) of the cylinder block 12 in the upstream region 12UA. However, similar to the content described regarding the above heating mechanism 14, in order to be able to uniformly heat the cylinder block 12 provided with the auxiliary heating mechanism 18, it is preferably arranged to surround the outer periphery of the cylinder block 12. In addition, the auxiliary heating mechanism 18 can also be configured to have a structure in which a plurality of auxiliary heating mechanisms are provided and the heated fluid (refrigerant) can flow through them respectively.

[0058] The vent part 19 is a component provided on the cylinder block 12 and is used to discharge the gas generated inside the cylinder block 12 to the outside of the cylinder block 12. As described above, the vent part 19 is provided in a manner connected to the upper surface opening 12c of the cylinder block 12. By providing the vent part 19, gas will not accumulate inside the cylinder block 12 and it will not be in an unnecessary pressurized state or the like.

[0059] The position where the vent part 19 is provided can be set at any position of the cylinder block 12, and it is preferably provided in the downstream region 12DA where gas is likely to be generated. In Figure 1 an example is shown in which the vent part 19 is provided at one location, but it can also be provided at multiple locations. <

[0060] Next, the structure of the screw 12a inside the cylinder block 12 of the extrusion device 10 provided in the present embodiment will be described.

[0061] As described above, the screw 12a is a component that functions to convey the resin raw material and knead the resin raw material. On the screw 12a, for example, as Figure 2 shown, a conveying part 12a1 and a kneading part 12a2 can be provided according to its screw shape. At this time, it is preferable to arrange the conveying part 12a1 in the upstream region 12UA of the cylinder block 12 and the kneading part 12a2 in the downstream region 12DA of the cylinder block 12. In addition, the kneading part 12a2 can be arranged in the upstream region 12UA or the conveying part 12a1 can be arranged in the downstream region 12DA.

[0062] That is, the arrangement of the number, length, etc. of the conveying section 12a1 and the kneading section 12a2 can be set to any arrangement, as long as the optimal conditions are set according to the type of resin raw material used and the adjustment state of the heating temperature of the cylinder 12.

[0063] Here, as long as the conveying section 12a1 that mainly conveys the resin raw material is composed of a threaded screw and the kneading section 12a2 that mainly kneads the resin raw material is composed of a kneading screw. In Figure 3 a perspective view showing an example of the shape of a threaded screw is shown, and in Figure 4 a perspective view showing an example of the shape of a kneading screw is shown.

[0064] In addition, a threaded screw refers to a screw having a threaded shape, corresponding to a screw having threads formed on the outer peripheral side surface of the screw. As such a thread, a full thread shape or a square thread shape can be cited. The full thread shape is a thread shape in which two side surfaces (i.e., the upstream side surface and the downstream side surface) of the thread are formed in a curved surface (bent surface) shape. The full thread shape extends spirally on the side surface of the screw. In addition, the square thread shape is a thread shape formed such that two side surfaces (i.e., the upstream side surface and the downstream side surface) of the thread become surfaces (vertical surface shapes) substantially perpendicular to the outer peripheral side surface of the screw. The cross section of the square thread shape is rectangular. The square thread extends spirally on the side surface of the screw.

[0065] In addition, a kneading screw refers to a screw having a structure in which the rotational positions of a plurality of kneading disks overlap while being offset, as shown in Figure 4 Each kneading disk has a substantially elliptical shape and has a major axis portion and a minor axis portion.

[0066] In addition, the offset direction of the rotational positions of the plurality of kneading disks may be forward and reverse. Here, the forward direction corresponds to the case where the rotation of the kneading screw causes a feeding action of the resin raw material in the forward (downstream side) direction. The case where the rotational positions of the plurality of kneading disks are offset in the forward direction is called a forward kneading screw, and a forward kneading screw is shown in Figure 4 In the case of Figure 4 , for a plurality (here, five) of kneading disks having the same shape, the central axis directions are made to coincide, and the rotational positions (rotational positions around the central axis) overlap while being offset 45° each time in the forward direction.

[0067] In addition, the reverse direction corresponds to the case where the rotation of the kneading disk causes a feeding action of the resin raw material in the backward (upstream side) direction. The case where the rotational positions of the plurality of kneading disks are offset in the reverse direction is called a reverse kneading screw. At this time, it is possible to exemplify compared to Figure 4A structure arranged in such a way that the staggering directions of the kneading disks are opposite. In the case of reverse staggering, since the resin raw material is blocked in the kneading section provided with the kneading screw, a strong kneading effect can be obtained.

[0068] As described above, when transporting and kneading the resin raw material, the resin raw material is heated by the shear energy during kneading. Therefore, in such an extrusion device, there is a high possibility that the resin raw material is overheated in the kneading section 12a2 provided in the downstream region 12DA.

[0069] Therefore, it is preferable that the cooling mechanism 16 is provided corresponding to the arrangement position of the kneading section 12a2 provided in the downstream region 12DA of the cylinder 12. By arranging in such a corresponding relationship, when an overheated part is generated in the cylinder 12, the cooling mechanism 16 can be immediately operated to lower the temperature of the cylinder.

[0070] [Mixing method of resin raw material]

[0071] Next, regarding the mixing method of the resin raw material of the present embodiment, taking the case of implementing using the extrusion device 10 described above as an example, each process will be described. Figure 1 as an example

[0072] First, the resin raw material prepared as described above is supplied from the resin raw material supply section 11 into the cylinder 12. The resin raw material containing a thermoplastic resin or the like is, for example, put into the resin raw material supply section 11 (hopper) from above through a feeder or the like and supplied to the cylinder 12.

[0073] The resin raw material supplied to the cylinder 12 is transported in the cylinder 12 by the screw 12a arranged in the cylinder 12, and at the same time, it is heated and melted by the heating mechanism 14 provided outside the cylinder 12 and the energy generated when the screw 12a shears the resin raw material, and becomes a melt [(a) heating process].

[0074] This (a) heating process is carried out in the upstream region 12UA of the cylinder 12. In the present embodiment, the temperature during heating, melting, kneading and other processes in the upstream region 12UA is usually about 100 - 300 °C, preferably about 100 - 250 °C.

[0075] Next, the obtained melt passes through the cylinder 12 through the screw 12a and is transported to the downstream side (discharge section 15 side). During this transportation, the raw material is sufficiently kneaded to become a uniform kneaded product. During this transportation, the temperature inside the cylinder 12 is maintained to ensure the smooth flow of the kneaded product. That is, the heated temperature is maintained here or the temperature at which the kneaded product can flow is maintained.

[0076] In the present embodiment, the temperature of the cylinder block 12 is adjusted and controlled such that the temperature of the resin raw material becomes a specified temperature. For example, the cylinder block 12 is formed by connecting a plurality of cylinder blocks, and a heating mechanism 14 and a thermometer capable of measuring the temperature of the cylinder block are provided for each cylinder block, so that while monitoring the measured value measured by the thermometer, the output of the heating mechanism 14 is controlled such that each cylinder block becomes the set temperature.

[0077] At this time, in the upstream region 12UA and the downstream region 12DA, although the cylinder blocks are respectively controlled to become the specified temperature, as described above, there is a case where the molten resin becomes a temperature higher than the set temperature due to the shear energy generated by the rotation of the screw 12a. In the present embodiment, when it is detected that the temperature of the cylinder block is higher than the set temperature in this way, a cooling fluid (refrigerant) is supplied to the cooling mechanism 16 provided in the cylinder block, and the temperature of the cylinder block is lowered by heat exchange [(b) cooling process]. That is, the heat exchange based on the fluid (refrigerant) is performed as needed, and the cooling based on the fluid (refrigerant) does not need to be always performed.

[0078] In addition, when the cooling mechanism 16 is provided at a plurality of positions of the cylinder block 12, even when the fluid (refrigerant) is supplied, it is possible to determine whether to supply the fluid (refrigerant) to all the cooling mechanisms 16 or to a part of the cooling mechanisms 16 according to the temperature of the cylinder block provided with the cooling mechanism 16.

[0079] In addition, although the heat exchange based on the fluid (refrigerant) is performed as described above for the cylinder block 12 in the downstream region 12DA when the temperature is higher than its set temperature, it is preferably to change the supply amount of the fluid (refrigerant) according to the temperature difference between the set temperature and the actual temperature (measured value) in terms of effective temperature management.

[0080] For example, when the measured value is about 1 to 2 °C higher than the set temperature, the supply of the fluid (refrigerant) is not started, but the temperature change is observed more carefully. Thus, when the temperature rises and the measured value is about 3 to 4 °C higher, it operates in such a way that a small amount of the fluid (refrigerant) is supplied to the cooling mechanism 16. When the temperature further rises and the measured value is more than 5 °C higher than the set temperature, the supply of the fluid (refrigerant) to the cooling mechanism 16 is increased so that a large amount of the fluid (refrigerant) is supplied. When the measured value is more than 30 °C higher, the supply of the refrigerant can be changed according to the situation, such as adjusting the supply of the refrigerant to the maximum.

[0081] Here, the heat exchange based on the fluid (refrigerant) is performed by supplying the fluid (refrigerant) to the cooling mechanism 16. That is, when the fluid (refrigerant) is supplied from the fluid supply port 16a to the cooling mechanism 16, the fluid (refrigerant) circulates in the flow path provided inside while performing heat exchange with the cylinder block 12, reducing the temperature of the cylinder block 12. Thereby, the temperature of the molten resin in the cylinder block 12 can be reduced to suppress overheating. The fluid (refrigerant) heated by the heat exchange is discharged from the fluid discharge port 16b.

[0082] In this way, while adjusting the temperature of the molten resin, the molten resin is extruded and discharged from the discharge portion 15 provided at the front end of the cylinder block 12 [(c) discharge process]. The extruded molten resin is discharged from the molding holes provided in the discharge portion 15, cooled to the external gas ambient temperature, and solidified into the shape of the molding holes. The solidified molded product is further passed through water or the like for cooling to reduce the temperature, thereby enabling it to become a resin material.

[0083] The shape of the resin material obtained here is not particularly limited, and examples include strand shape or sheet shape. The resin material formed into a strand shape or a sheet shape is cut into a desired size and can be used as a molding material for resin products.

[0084] Moreover, in the present embodiment, it is characterized in that the heated fluid (refrigerant) obtained in the above-mentioned step (b) is transported to the upstream region 12UA, and the thermal energy possessed by the heated fluid (refrigerant) is used to heat the cylinder block 12 in the upstream region 12UA.

[0085] Specifically, the heated fluid (refrigerant) discharged from the fluid discharge port 16b is supplied to the auxiliary heating mechanism 18 provided in the upstream region 12UA through the pipe 17. The heated fluid (refrigerant) supplied to the auxiliary heating mechanism 18 in this way is supplied from the heating fluid inlet 18a to the flow path provided inside the auxiliary heating mechanism 18, and while flowing in this flow path, the cylinder block 12 is heated through heat exchange. The fluid (refrigerant) whose temperature has been reduced by this heat exchange is discharged from the heating fluid discharge port 18b.

[0086] Here, the auxiliary heating mechanism 18 is provided in a portion where the temperature of the cylinder block 12 is lower than the temperature of the heated fluid (refrigerant). This is because in order to raise the temperature of the cylinder block 12 through heat exchange as described above, it is necessary to make the relationship between the temperature of the heated fluid (refrigerant) and the temperature of the cylinder block 12 the above-mentioned relationship in advance.

[0087] Here, it is preferable that the temperature of the heated fluid (refrigerant) is 5°C or more higher than the temperature of the cylinder block 12 provided with the auxiliary heating mechanism 18, and more preferably 20°C or more higher. The greater the temperature difference, the more efficiently the cylinder block 12 can be heated.

[0088] In addition, when the auxiliary heating mechanism 18 is provided at multiple parts of the cylinder block 12, it is only necessary to determine whether to supply the heated fluid (refrigerant) to all of the auxiliary heating mechanisms 18 or to a part of the auxiliary heating mechanisms 18 according to the temperature of the cylinder block provided with the auxiliary heating mechanism 18.

[0089] In addition, although the heat exchange based on the heated fluid (refrigerant) is performed on the cylinder block 12 provided with the auxiliary heating mechanism 18 as described above, from the aspect of effective temperature management, it is preferable to change the supply amount of the heated fluid (refrigerant) according to the temperature difference between its set temperature and the actual temperature (measured value).

[0090] As described above, the extrusion device 10 of the present embodiment has a heating mechanism 14 for supplying thermal energy and a cooling mechanism 16 for discharging thermal energy. If the extrusion device is operated in a manner that makes them independent, the thermal energy will be wasted. In this regard, in the present embodiment, the thermal energy discharged from the cooling mechanism 16 is utilized in the auxiliary heating mechanism 18, which is an excellent device that can effectively and flexibly utilize the thermal energy and improve the energy utilization efficiency of the entire extrusion device.

[0091] In addition, as the fluid for cooling used herein, water, an ethylene glycol aqueous solution, oil, etc. can be used. From the viewpoints of cost and environmental issues, etc., it is preferably a water-cooled method using water. At this time, although there is a case where the heated fluid obtained by the cooling mechanism 16 becomes a temperature above the boiling point of the fluid, in order to efficiently perform the heat exchange based on the auxiliary heating mechanism 18, it is preferable to supply the heated fluid (refrigerant) as a fluid (refrigerant) in a high-temperature state by applying pressure to the heated fluid (refrigerant). In this case, it is only necessary to provide a pressure pump for the pipe connected to the fluid supply port 16a and a pressure regulating valve at the outlet to supply the fluid (refrigerant) by pressurizing it to a pressure above a specified value.

[0092] <Embodiment 2>

[0093] While referring to Figure 5 While explaining the overall structure of the extrusion device in the present embodiment and the kneading method of the resin raw material using the extrusion device.

[0094] [Extrusion Device]

[0095] Figure 5FIG. 0 is an explanatory diagram showing a schematic structure of the extrusion device 20 of Embodiment 2. The extrusion device 20 is a device used to soften and melt a resin raw material by heating it inside, and extrude the molten resin from a discharge portion provided at its front end to obtain a molding resin material in which the resin raw material is sufficiently kneaded.

[0096] The extrusion device 20 includes: a resin raw material supply unit 11: a cylinder 12 having an upstream region 12UA and a downstream region 12DA and provided with a screw inside; a rotational drive mechanism 13 for driving the screw in the cylinder 12; a heating mechanism 14 provided in the upstream region 12UA; a discharge portion 15; and a cooling mechanism 16 provided in the downstream region 12DA.

[0097] In addition, the extrusion device 20 includes: a pipe 17 connecting the upstream region 12UA and the downstream region 12DA and connected to the cooling mechanism 16; an auxiliary heating mechanism 18 provided in the upstream region 12UA and connected to the pipe 17; and a vent portion 19 capable of discharging the gas generated in the cylinder.

[0098] Moreover, the extrusion device 20 includes a circulation pipe 21 for circulating a cooling fluid, a pressurizing mechanism 22, a pressure adjusting mechanism 23, and a condensation mechanism 24. That is, it is characterized in that it can be used by circulating the cooling fluid. This embodiment is different from Embodiment 1 only in that it has a structure for circulating the cooling fluid, and the other structures are the same. Hereinafter, the description of the structures that are the same as those already described will be omitted, and the different parts will be described in detail.

[0099] The circulation pipe 21 is a pipe connected to the fluid supply port 16a and the heating fluid discharge port 18b and capable of circulating the fluid used for auxiliary heating discharged from the heating fluid discharge port 18b to the fluid supply port 16a. In this way, by recycling the fluid (refrigerant) used in the heat exchange, the cooling in the cooling mechanism 16 and the heating in the auxiliary heating mechanism 18 can be efficiently performed.

[0100] In the circulation pipe 21, a pressurizing mechanism 22, a pressure adjusting mechanism 23, and a condensation mechanism 24 are provided so that the fluid (refrigerant) can efficiently and continuously play a prescribed role in a cycle. With such a structure, in the Figure 5 extrusion device 20 shown, the fluid (refrigerant) is heated in the cooling mechanism 16 as described above, and then cooled in the auxiliary heating mechanism 18.

[0101] The pressurizing mechanism 22 functions to put the fluid (refrigerant) in a pressurized state during the heat exchange performed by the cooling mechanism 16 and the auxiliary heating mechanism 18. Examples of the pressurizing mechanism include a pressurizing pump such as a piston pump. In the present embodiment, when water is used as the fluid (refrigerant), for example, it is sufficient to have a pressure at the saturated vapor pressure level of 1.55 MPa when the cylinder temperature in the downstream region 12DA is 200°C, 8.58 MPa when it is 300°C, and 16.5 MPa when it is 250°C. Preferably, it has a pressure corresponding to the cylinder temperature.

[0102] The pressure adjusting mechanism 23 functions to reduce the pressure of the fluid (refrigerant) pressurized by the pressurizing mechanism 22 and to supply the fluid (refrigerant) to the pressurizing mechanism 22 via the circulation pipe 21. Examples of the pressure adjusting mechanism include a pressure regulating valve. In the present embodiment, when water is used as the fluid (refrigerant), for example, it preferably has a pressure at the saturated vapor pressure level of the fluid (refrigerant) whose temperature is reduced by the heat exchange in the auxiliary heating mechanism 18.

[0103] The condensation mechanism 24 is not an essential structure and can be provided as needed. When all or most of the fluid (refrigerant) decompressed by the above pressure adjusting mechanism 23 is gas, it functions to condense at least a part of it to form a liquid fluid (refrigerant). Examples of the condensation mechanism include a cooler having a mechanism for cooling the fluid (refrigerant). In the present embodiment, when water is used as the fluid (refrigerant), a known condensation mechanism, so-called a condenser, can be used.

[0104] Moreover, in the present embodiment, by performing the same operations as in Embodiment 1 using the extrusion device 20, the resin raw material can be kneaded. That is, (a) a heating process, (b) a cooling process, and (c) a discharging process are performed, and the heated fluid (refrigerant) obtained by the cooling mechanism 16 is used for auxiliary heating in the auxiliary heating mechanism 18.

[0105] In the present embodiment, the fluid (refrigerant) obtained by the auxiliary heating mechanism 18 is further circulated in the above circulation pipe 21 and supplied again to the cooling mechanism 16. Hereinafter, the state of the fluid (refrigerant) included, the fluid (refrigerant) passes from the cooling mechanism 16 through the pipe 17, passes through the auxiliary heating mechanism 18, and then reaches the cooling mechanism 16 via the circulation pipe 21.

[0106] First, a fluid (refrigerant) at room temperature is sent out in a pressurized state by a pressurizing mechanism 22, and the low-temperature and high-pressure fluid (refrigerant) is introduced into a cooling mechanism 16. The fluid (refrigerant) introduced into the cooling mechanism 16 reduces the temperature of the cylinder block 12 through heat exchange with the cylinder block 12, and at the same time, the fluid (refrigerant) is heated up and becomes a high-temperature and high-pressure heated fluid (refrigerant). At this time, although the heated fluid (refrigerant) becomes a high-temperature and high-pressure liquid or gas (vapor) according to its pressure and temperature, it is preferably in a condition of being a gas (vapor) or a mixed fluid of gas (vapor) and liquid.

[0107] The obtained heated fluid (refrigerant) is introduced into an auxiliary heating mechanism 18 through a pipe 17. The fluid (refrigerant) introduced into the auxiliary heating mechanism 18 raises the temperature of the cylinder block 12 through heat exchange with the cylinder block 12 as described above, and at the same time, the fluid (refrigerant) is cooled down. At this time, although the temperature of the fluid (refrigerant) decreases, it is still in a high-temperature state as the state of the fluid (refrigerant) in this cycle. In addition, when the fluid (refrigerant) introduced into the auxiliary heating mechanism 18 at this time is a gas (vapor) or a mixed fluid of gas (vapor) and liquid, the discharged fluid (refrigerant) returns to a liquid or the proportion of the liquid increases due to the decrease in its temperature. Therefore, the fluid (refrigerant) discharged from the auxiliary heating mechanism 18 is a high-temperature and high-pressure liquid or a mixed fluid of vapor and liquid, and they are sent to a pressure adjusting mechanism 23.

[0108] Next, through a pressure adjusting mechanism 23 such as a pressure adjusting valve, its pressure is reduced to become a high-temperature and low-pressure state of a liquid or a mixed fluid of vapor and liquid. Moreover, this high-temperature and low-pressure mixed fluid is cooled and condensed (liquefied) by a condensing mechanism 24 as needed, and a part of it is liquefied. In addition, the cooling in the condensing mechanism 24 is usually carried out through heat exchange. This liquid or mixed fluid of vapor and liquid is pressurized again by a pressurizing mechanism 22 and supplied to the cooling mechanism 16.

[0109] The low-temperature and high-pressure fluid (refrigerant) supplied to the cooling mechanism 16 in this way can continuously repeat the actions of being heated again through heat exchange in the cooling mechanism 16 and then being cooled through heat exchange in the auxiliary heating mechanism 18 as described above.

[0110] According to the above principle, the fluid (refrigerant) is recycled, and thus in the extrusion device 20, the thermal energy obtained through heat exchange in the cooling mechanism in 16 can be utilized for heating the cylinder block 12 through heat exchange in the auxiliary heating mechanism 18, so that the extrusion device can operate with less energy loss.

[0111] 〔Modification Example 1〕

[0112] In the above-described Embodiment 1 or 2, the gist of being able to provide a plurality of auxiliary heating mechanisms 18 was described. Hereinafter, a specific example (Modification 1) in the case of providing a plurality of auxiliary heating mechanisms 18 will be described.

[0113] Figure 6 FIG. is an explanatory diagram showing a schematic structure of the extrusion device 30 of this Modification 1. The extrusion device 30 includes: a resin raw material supply unit 11; a cylinder 12 having an upstream region 12UA and a downstream region 12DA and provided with a screw therein; a rotational drive mechanism 13 for driving the screw in the cylinder 12; a heating mechanism 14 provided in the upstream region 12UA; a discharge unit 15; and a cooling mechanism 16 provided in the downstream region 12DA.

[0114] In addition, the extrusion device 30 includes: a pipe 17 that connects the upstream region 12UA and the downstream region 12DA and is connected to the cooling mechanism 16; an auxiliary heating mechanism 18 provided in the upstream region 12UA and connected to the pipe 17; and a ventilation unit 19 that can discharge the gas generated in the cylinder.

[0115] Here, a plurality of auxiliary heating mechanisms 18 are provided in the extrusion device 30. These auxiliary heating mechanisms 18 have the same structure as the extrusion device 10 described above, except that they are connected to adjacent auxiliary heating mechanisms 18 through a pipe 31. Hereinafter, the differences will be mainly described, and the description of the same structure will be omitted.

[0116] As Figure 6 shown, the extrusion device 30 of this Modification 1 is provided with a plurality of auxiliary heating mechanisms 18 in the upstream region 12UA of the cylinder 12. And, regarding this auxiliary heating mechanism 18, adjacent auxiliary heating mechanisms 18 are respectively connected through a pipe 31. That is, the heating fluid inlet 18a of the auxiliary heating mechanism 18 provided on the most downstream side (discharge unit 15 side) is connected to the fluid discharge port 16b of the cooling mechanism 16 through a pipe 17.

[0117] The heating fluid inlet 18a of the other auxiliary heating mechanisms 18 is connected to the heating fluid discharge port 18b of the adjacent auxiliary heating mechanism 18 through a pipe 31. And, the fluid (refrigerant) for auxiliary heating is discharged to the outside from the heating fluid discharge port 18b of the auxiliary heating mechanism 18 provided on the most upstream side (resin raw material supply unit 11 side). That is, it is possible to connect a plurality of auxiliary heating mechanisms 18 provided along the conveyance direction of the resin raw material in the cylinder 12 in series through a pipe 31.

[0118] Due to having the above-described structure, the fluid (refrigerant) used in the first modification example is heated by heat exchange in the cooling mechanism 16 and then flows through the pipe 17. First, it flows through the auxiliary heating mechanism 18 on the most downstream side (the discharge portion 15 side), heats the cylinder block 12 through heat exchange, and then flows through the second auxiliary heating mechanism 18 on the downstream side (the discharge portion 15 side) in the auxiliary heating mechanism 18, heating the cylinder block 12 through heat exchange. In this way, it sequentially flows through the auxiliary heating mechanism 18 from the downstream side (the discharge portion 15 side) to heat the cylinder block 12.

[0119] At this time, the temperature of the heated fluid (refrigerant) decreases through heat exchange. On the other hand, the temperature of the cylinder block 12 is stepwise heated from the upstream side (the resin raw material supply portion 11 side) to the downstream side (the discharge portion 15 side) in the upstream region 12UA. In other words, the cylinder block 12 is in a state where the temperature becomes lower from the downstream side (the discharge portion 15 side) toward the upstream side (the resin raw material supply portion 11 side). Therefore, even the fluid (refrigerant) whose temperature temporarily decreases in the auxiliary heating mechanism 18 can be reused for the auxiliary heating of the cylinder block 12 at a position upstream of it.

[0120] The fluid (refrigerant) that has flowed through all the auxiliary heating mechanisms 18 and whose temperature has decreased is discharged from the heating fluid discharge port 18b located on the most upstream side and is processed or recycled.

[0121] At this time, in order to effectively perform heating, it is preferable to set the temperature of the cylinder block 12 provided with the auxiliary heating mechanism 18 and the temperature of the supplied fluid (refrigerant) such that the temperature of the supplied fluid (refrigerant) is higher than the temperature of the cylinder block 12. In this way, the cylinder block 12 can be heated in any of the auxiliary heating mechanisms 18.

[0122] By adopting such a structure, the thermal energy of the heated fluid (refrigerant) can be effectively utilized in the extrusion device 30, which is therefore preferable.

[0123] 〔Second Modification Example〕

[0124] In addition, in the above-described Embodiment 1 or 2, the main idea of being able to provide a plurality of auxiliary heating mechanisms 18 is described. The following describes a specific example (Second Modification Example) in the case of providing a plurality of auxiliary heating mechanisms 18.

[0125] Figure 7It is an explanatory diagram showing the schematic structure of the extrusion device 40 of this second modification example. The extrusion device 40 includes: a resin raw material supply unit 11; a cylinder 12 having an upstream region 12UA and a downstream region 12DA and provided with a screw inside; a rotational drive mechanism 13 for driving the screw in the cylinder 12; a heating mechanism 14 provided in the upstream region 12UA; a discharge unit 15; and a cooling mechanism 16 provided in the downstream region 12DA.

[0126] In addition, the extrusion device 40 includes: a pipe 41 connecting the upstream region 12UA and the downstream region 12DA and connected to the cooling mechanism 16; an auxiliary heating mechanism 18 provided in the upstream region 12UA and connected to the pipe 43; and a vent part 19 capable of discharging the gas generated in the cylinder.

[0127] Here, a plurality of auxiliary heating mechanisms 18 are provided in the upstream region 12UA of the cylinder 12 of the extrusion device 40. The heating fluid inlets 18a of these auxiliary heating mechanisms 18 are respectively connected to the fluid outlets 16b of the cooling mechanism 16 through the pipe 41, and flow rate adjustment mechanisms 42 are respectively provided on the flow paths extending from the pipe 41 to the heating fluid inlets 18a. In addition, the heating fluid outlets 18b are respectively connected to the pipe 43. The extrusion device 40 has the same structure as the extrusion device 10 described above except for these aspects. Hereinafter, the differences will be mainly described, and the description of the same structure will be omitted.

[0128] The extrusion device 40 of this second modification example is provided with a plurality of auxiliary heating mechanisms 18 in the upstream region 12UA of the cylinder 12. And these auxiliary heating mechanisms 18 are respectively connected to the cooling mechanism 16 through the pipe 41. That is, the heating fluid inlets 18a of all the auxiliary heating mechanisms 18 are connected to the fluid outlets 16b of the cooling mechanism 16 through the pipe 41. That is, it is possible to make a plurality of auxiliary heating mechanisms 18 arranged along the conveying direction of the resin raw material in the cylinder 12 be connected in parallel through the pipe 41.

[0129] Due to having the above structure, the fluid (refrigerant) used in this second modification example is heated by heat exchange in the cooling mechanism 16, then flows through the pipe 41, and is supplied to each auxiliary heating mechanism 18. The fluid (refrigerant) supplied to the auxiliary heating mechanism 18 flows through the auxiliary heating mechanism 18, and can heat the cylinder 12 through heat exchange. At this time, through heat exchange, the temperature of the fluid (refrigerant) decreases, and the fluid (refrigerant) with the decreased temperature is discharged from the heating fluid outlet 18b. Here, each heating fluid outlet 18b is connected to the pipe 43, and after merging, it is processed or recycled.

[0130] As described above, the cylinder block 12 is usually heated by the heating mechanism 14, but its temperature is set to increase stepwise gradually from the resin raw material supply unit 11 side. Therefore, in the case where a plurality of auxiliary heating mechanisms 18 are connected as in the present embodiment, the amount of the heated fluid (refrigerant) introduced from the pipe 41 can be changed for each auxiliary heating mechanism 18.

[0131] That is, it is preferable to change the supply amount according to the temperature difference between the temperature of the cylinder block 12 and the temperature of the heated fluid (refrigerant). For example, since the temperature of the cylinder block 12 is heated stepwise as described above, the temperature of the cylinder block 12 on the downstream side (discharge unit 15 side) is high, and the temperature of the cylinder block 12 on the upstream side (resin raw material supply unit 11 side) is low. Therefore, the temperature difference between the temperature of the cylinder block 12 and the temperature of the heated fluid (refrigerant) is small on the downstream side (discharge unit 15 side) and large on the upstream side (resin raw material supply unit 11 side).

[0132] Then, in the auxiliary heating mechanism 18 provided on the downstream side (discharge unit 15 side), the supply amount of the heated fluid (refrigerant) is increased so that the amount of energy for heat exchange can be ensured even if the temperature difference is small. In the auxiliary heating mechanism 18 provided on the upstream side (resin raw material supply unit 11 side), since the temperature difference is large, the amount of energy for heat exchange can be easily ensured, and thus the supply amount of the fluid (refrigerant) can be adjusted in a reduced manner to avoid overheating.

[0133] In this way, by reducing the supply amount of the heated fluid (refrigerant) introduced into the auxiliary heating mechanism 18 stepwise from the downstream side (discharge unit 15 side) toward the upstream side (resin raw material supply unit 11 side), the thermal energy of the heated fluid (refrigerant) can be effectively utilized, which is preferable.

[0134] The adjustment of the supply amount can be performed by the above-described flow rate adjustment mechanism 42, or the temperature of the cylinder block 12 at the portion where the auxiliary heating mechanism 18 is provided can be measured by a thermometer or the like, and the supply amount can be adjusted according to the measurement result. Regarding the adjustment of the supply amount, it is only necessary to provide a control unit for adjusting it, and it can also be performed in the same control unit as the control unit for adjusting the temperature of the cylinder block 12 by the heating mechanism 14.

[0135] In addition, in the above-described modification 1 and modification 2, the case where a plurality of auxiliary heating mechanisms 18 are provided and connected in series or in parallel is described. Similarly, a plurality of cooling mechanisms 16 can be provided and connected in series or in parallel.

[0136] This can be applied to any embodiment and variation. The connection method of each cooling mechanism 16 and the connection method of each auxiliary heating mechanism 18 can be set as independent methods. That is, it can be set in forms such as a form in which a plurality of cooling mechanisms 16 are connected in series and a plurality of auxiliary heating mechanisms 18 are also connected in series, a form in which a plurality of cooling mechanisms 16 are connected in series and a plurality of auxiliary heating mechanisms 18 are connected in parallel, a form in which a plurality of cooling mechanisms 16 are connected in parallel and a plurality of auxiliary heating mechanisms 18 are connected in series, a form in which a plurality of cooling mechanisms 16 are connected in parallel and a plurality of auxiliary heating mechanisms 18 are also connected in parallel, and other connection methods.

[0137] <Embodiment 3>

[0138] Next, while referring to Figure 8 an extrusion device and a method for kneading a resin raw material of other embodiments will be described.

[0139] Figure 8 The extrusion device shown has a structure in which fifteen cylinder blocks (C1 to C15) are connected to form one cylinder as a twin-screw kneading extruder, and further, flow paths through which a cooling fluid can flow are provided inside the cylinder walls of these cylinder blocks. In addition, in the extrusion device 50 used in this embodiment, a pipe 17 is provided in such a way that the flow paths of adjacent cylinder blocks of cylinder blocks C15 to C11 are connected in series, and the flow paths of adjacent cylinder blocks of cylinder blocks C6 to C2 are connected in series, and the fluid discharge port of cylinder block C11 is connected to the heating fluid inlet of cylinder block C6, and the structure is shown.

[0140] In this Figure 8 the flow path of the fluid (refrigerant) is simply shown, and the part entering the area of the cylinder block shows the flow path of the fluid (refrigerant) formed inside the cylinder wall. In addition, the flow path of the fluid (refrigerant) formed in this cylinder block is formed along the outer periphery of the cylinder block so as to be able to uniformly cool the cylinder block.

[0141] In addition, a plunger pump 51 is provided as a pressurizing mechanism in the extrusion device 50, and the fluid (refrigerant) can be sent to cylinder block C15 in a pressurized state. The fluid (refrigerant) sequentially flows through the flow paths of each cylinder block from cylinder block C15 to cylinder block C11, and if it is discharged from cylinder block C11, it flows in the pipe 17. The pipe 17 is connected to cylinder block C6, and then, the fluid (refrigerant) sequentially flows through the flow paths of each cylinder block from cylinder block C6 to cylinder block C2, and if it is discharged from cylinder block C2, it becomes a gas through the pressure regulating valve 52 and is released into the external gas environment.

[0142] That is, it is configured such that the fluid (refrigerant) flows in a direction opposite to the conveyance direction of the resin raw material. Further, due to the above structure, the fluid (refrigerant) can be maintained in a pressurized state between the plunger pump 51 and the pressure regulating valve 52. In addition, in the extrusion device 50, a flow meter 53, a thermometer 54, and a pressure gauge 55 are respectively provided in the flow path through which the fluid for cooling flows.

[0143] The resin raw material can be kneaded using the extrusion device 50 as follows. First, polypropylene pellets are prepared as the resin raw material and talc is prepared as the filler. These polypropylene and talc are supplied from the resin raw material supply unit 11 so as to have a desired mixing ratio, for example, 40% by mass of talc, and are gradually heated and melted in the upstream region 12UA of the cylinder block 12. Then, the resin raw material is kneaded while maintaining the melting temperature in the downstream region 12DA of the cylinder block 12, and is discharged from the discharge unit after sufficient kneading.

[0144] At this time, when the cylinder temperature in the downstream region 12DA is higher than the set temperature, cooling water (pure water at room temperature) is supplied as the cooling fluid from the plunger pump 51 at, for example, 4.8 L / min. The supplied cooling water flows from the cylinder block C15 to the cylinder block C11 and circulates in the flow path provided in the cylinder wall of each cylinder block. While being gradually heated through heat exchange with the cylinder block 12, it is discharged from the cylinder block C11 to the pipe 17.

[0145] Next, the cooling water is circulated in the pipe 17 and then introduced into the cylinder block C6. However, in the pipe 17, the cooling water flows in the form of high-temperature and high-pressure steam with a maximum vapor internal pressure of 3 MPa and a temperature of 240 °C, for example.

[0146] The high-temperature and high-pressure steam thus obtained then flows from the cylinder block C6 to the cylinder block C2 in the flow path provided in the cylinder wall of each cylinder block. Since the cylinder blocks C6 to C2 are lower in temperature than the obtained high-temperature and high-pressure steam, the high-temperature and high-pressure steam is gradually cooled while exchanging heat with the cylinder block 12 and is discharged from the cylinder block C2. The high-temperature and high-pressure steam is cooled through heat exchange in the upstream region 12UA and partially liquefies, and is depressurized through the pressure regulating valve 52, so that it can be directly discharged to the external gas environment.

[0147] Regarding Figure 8 the extrusion device 50 with such a structure, it can be seen that compared with the conventional kneading process of the filler mixture using an extrusion device with a structure in which cooling water is supplied to the extrusion device 50 at atmospheric pressure and discharged as warm water from the cylinder block C11 without providing the pipe 17, the heater output can be reduced by about 41%, and the heater output can be further reduced in the kneading process with excessive energy.

[0148] As described above, according to this embodiment, it can be understood that the present invention is an excellent extrusion device as follows: by using a fluid for cooling, the thermal energy obtained in the downstream region 12DA is utilized for heating in the upstream region UA, the energy in the extrusion device 50 can be effectively utilized flexibly, and thus energy loss can be reduced.

[0149] As described above, the present invention has been specifically described by way of embodiments and examples. However, the present invention is not to be construed as being limited to these embodiments and examples, and various modifications can be made without departing from the gist thereof.

[0150] Explanation of Reference Numerals

[0151] 10, 20, 30, 40, 50 Extrusion Device

[0152] 11 Resin Raw Material Supply Unit

[0153] 12 Cylinder

[0154] 12a Screw

[0155] 12b, 12c Upper Surface Opening

[0156] 12UA Upstream Region

[0157] 12DA Downstream Region

[0158] 13 Rotation Driving Mechanism

[0159] 14 Heating Mechanism

[0160] 15 Discharge Unit

[0161] 16 Cooling Mechanism

[0162] 17, 31, 41, 43 Pipe

[0163] 18 Auxiliary Heating Mechanism

[0164] 19 Ventilation Unit

[0165] 21 Circulation Pipe

[0166] 22 Pressurizing Mechanism

[0167] 23 Pressure Adjusting Mechanism

[0168] 24 Condensation Mechanism

[0169] 42 Flow Rate Adjusting Mechanism

[0170] 51 Plunger Pump

[0171] 52 Pressure Adjusting Valve

[0172] 53 Flowmeter

[0173] 54 Thermometer

[0174] 55 Manometer.

Claims

1. An extrusion device, comprising the following: A cylinder having a first region and a second region; A supply section for a resin raw material provided on the first region side of the cylinder; A screw disposed in the cylinder for transporting and kneading the resin raw material; A discharge section for the resin raw material provided on the second region side of the cylinder; A heating mechanism for heating the resin raw material provided in the first region of the cylinder; A cooling mechanism for cooling the cylinder provided in the second region of the cylinder; And A pipe configured to connect the first region and the second region of the cylinder and connected to the cooling mechanism.

2. The extrusion device according to claim 1, wherein The cooling mechanism is a cooling method based on heat exchange using a fluid, and has a first flow path through which the fluid flows.

3. The extrusion device according to claim 2, wherein The cooling mechanism is a water cooling method, Steam or a mixture of steam and water flows in the pipe.

4. The extrusion device according to claim 2, wherein The first flow path of the cooling mechanism is formed inside the cylinder wall constituting the cylinder.

5. The extrusion device according to claim 2, wherein It has a second flow path through which the heated fluid obtained from the cooling mechanism flows, and has an auxiliary heating mechanism capable of heating the cylinder in the first region by heat exchange using the heated fluid.

6. The extrusion device according to claim 5, wherein It has a plurality of the auxiliary heating mechanisms, and the second flow paths of adjacent auxiliary heating mechanisms are connected to each other.

7. The extrusion device according to claim 5, wherein It has a plurality of the auxiliary heating mechanisms, and the second flow paths are each connected to the pipe.

8. The extrusion device according to claim 6, wherein It further has: A first thermometer for measuring the temperature of the heated fluid obtained from the cooling mechanism; A second thermometer for measuring the temperature of the cylinder in the first region; And A control unit that operates based on the measurement results of the first thermometer and the second thermometer so as to transport the heated fluid to the auxiliary heating mechanism disposed on the cylinder having a temperature lower than the temperature of the heated fluid.

9. The extrusion device according to claim 1, wherein The screw has a transport section and a kneading section, The transport section is disposed in the first region of the cylinder, The kneading section is disposed in the second region of the cylinder.

10. The extrusion device according to claim 2, wherein It further has a circulation pipe for circulating the fluid flowing in the pipe from the first region to the cooling mechanism.

11. A method for kneading a resin raw material, comprising the following steps: (a) A step of heating and melting the resin raw material supplied to a cylinder having a first region and a second region while transporting it in the cylinder by a screw and heating it by a heating mechanism provided in the first region; (b) A step of cooling the cylinder by a cooling mechanism provided in the second region of the cylinder while kneading the resin raw material after the step (a). (c) step of discharging the kneaded mixture of the resin raw material from a discharge portion provided at the front end of the cylinder after the step (b); and (d) step of causing a fluid to flow from the second region to the first region.

12. The method for kneading a resin raw material according to claim 11, wherein the fluid in the step (d) flows through a pipe connecting the first region and the second region.

13. The method for kneading a resin raw material according to claim 12, wherein the cooling mechanism is a cooling method based on heat exchange using a fluid, and has a first flow path through which the fluid flows.

14. The method for kneading a resin raw material according to claim 13, wherein the cooling mechanism is a water cooling method, steam or a mixture of steam and water flows in the pipe.

15. The method for kneading a resin raw material according to claim 13, wherein the first flow path of the cooling mechanism is formed inside a cylinder wall constituting the cylinder.

16. The method for kneading a resin raw material according to claim 13, wherein in the step (d), there is a second flow path through which the heated fluid obtained from the cooling mechanism flows, and an auxiliary heating mechanism capable of heating the cylinder in the first region by heat exchange with the heated fluid is used to assist in heating the cylinder.

17. The method for kneading a resin raw material according to claim 16, wherein there are a plurality of the auxiliary heating mechanisms, and the second flow paths of adjacent auxiliary heating mechanisms are connected to each other.

18. The method for kneading a resin raw material according to claim 16, wherein there are a plurality of the auxiliary heating mechanisms, and the second flow paths are each connected to the pipe.

19. The method for kneading a resin raw material according to claim 17, wherein further, the temperature of the heated fluid obtained from the cooling mechanism is measured by a first thermometer, the temperature of the cylinder is measured by a second thermometer in the first region, based on the measurement results of the first thermometer and the second thermometer, the heated fluid is transported to the auxiliary heating mechanism disposed on the cylinder having a temperature lower than the temperature of the heated fluid.

20. The method for kneading a resin raw material according to claim 11, wherein the screw has a conveying portion and a kneading portion, the conveying portion is disposed in the first region of the cylinder, the kneading portion is disposed in the second region of the cylinder.

21. The method for kneading a resin raw material according to claim 13, wherein ​

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