Extruder

Abstract

The kneading region (AR2) (cross-sectional area S2) is larger than the supply region (AR1) (cross-sectional area S1) (S2 > S1) in terms of the cross-sectional area inside the pair of cylinders (21, 22) in the direction orthogonal to the direction from the supply region (AR1) toward the kneading region (AR2). Therefore, the residence time of resin raw materials (resin pellets (PR) and molten resin (MR)) can be prolonged and the processing capacity can be improved without increasing the size of the extruder (10), i.e., not increasing the size of the pair of cylinders (21, 22) and the screw (50) or not increasing the diameter of the pair of cylinders (21, 22) and the screw (50). As a result, the extruder (10) can be easily used for a wide range of melt-kneading applications, in which a resin raw material for which the residence time needs to be extended can be easily handled.

Description

Technical Field

[0001] The present invention relates to an extruder for melting and kneading a resin raw material. Background Art

[0002] For example, Patent Document 1 describes an extruder for melting and kneading a resin raw material. The extruder described in Patent Document 1 includes a cylinder and a screw, and the screw is disposed inside the cylinder. Thus, the resin raw material supplied to the inside of the cylinder from the inlet is transported to the outlet while being melted and kneaded as the screw rotates.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2016-087896 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The cross-sectional area inside the cylinder of the extruder generally remains constant from the resin raw material inlet to the outlet. Therefore, it is necessary to increase the size of the extruder in order to improve the processing capacity.

[0008] Other problems and new features can be understood from the description of the present specification and the drawings.

[0009] Means for Solving the Problems

[0010] In the extruder disclosed in one embodiment of the present application, the cross-sectional area inside the cylinder is larger in one region than in other regions.

[0011] Effects of the Invention

[0012] According to one embodiment, it is possible to improve the processing capacity of the resin raw material without increasing the size of the extruder. Brief Description of the Drawings

[0013] Figure 1 is a partial cross-sectional view showing the structure of the extruder.

[0014] Figure 2 is a cross-sectional view showing the kneading portion of Embodiment 1.

[0015] Figure 3 is along Figure 2 cross-sectional views taken along line A-A and line C-C of.

[0016] Figure 4 is along Figure 2 cross-sectional views taken along line B-B of.

[0017] Figure 5AIt is a perspective view showing the forward feed screw fins.

[0018] Figure 5B It is a view showing the forward feed screw fins when observed from the side.

[0019] Figure 6A It is a perspective view showing the forward feed kneading part.

[0020] Figure 6B It is a view showing the forward feed kneading part when observed from the side.

[0021] Figure 7 It is a table comparing the residence times of Embodiment 1 and the comparative example.

[0022] Figure 8 It is a cross-sectional view showing the kneading treatment part of Embodiment 2.

[0023] Figure 9 It is a cross-sectional view showing the kneading treatment part of Embodiment 3.

[0024] Figure 10A It is a perspective view showing the reverse feed screw fins.

[0025] Figure 10B It is a view showing the reverse feed screw fins when observed from the side.

[0026] Figure 11A It is a perspective view showing the reverse feed kneading part.

[0027] Figure 11B It is a view showing the reverse feed kneading part when observed from the side.

[0028] Figure 12 It is a view showing Embodiment 4 corresponding to Figure 4 Corresponding figure.

[0029] Figure 13 It is a view showing Embodiment 5 corresponding to Figure 4 Corresponding figure.

[0030] Figure 14 It is a view showing Embodiment 6 corresponding to Figure 4 Corresponding figure.

[0031] Figure 15 It is a view showing Embodiment 7 corresponding to Figure 4 Corresponding figure.

[0032] Figure 16 It is a view showing Embodiment 8 corresponding to Figure 4 Corresponding figure.

[0033] Figure 17 It is a view showing Embodiment 9 corresponding to Figure 4 Corresponding figure.

[0034] Figure 18 is a diagram corresponding to Embodiment 10 Figure 4 .

[0035] Figure 19 is a diagram corresponding to Embodiment 11 Figure 4 .

[0036] Figure 20 is a diagram corresponding to Embodiment 12 Figure 4 .

[0037] Figure 21 is a diagram corresponding to Embodiment 13 Figure 4 .

[0038] Figure 22 is an enlarged cross-sectional view of the kneading processing unit of Embodiment 14

[0039] Figure 23 is an enlarged cross-sectional view of the kneading processing unit of Embodiment 15

[0040] Figure 24 is a partial cross-sectional view of a part of the extruder of Embodiment 16

[0041] Figure 25 is a diagram corresponding to Embodiment 17 Figure 4 .

[0042] Figure 26 is a diagram corresponding to Embodiment 18 Figure 4 .

[0043] Figure 27 is a diagram corresponding to Embodiment 19 Figure 4 . Detailed Embodiments

[0044] Hereinafter, embodiments of the present invention 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, devices, etc. having the same or substantially the same functions are labeled with the same reference numerals, and repeated descriptions are omitted.

[0045] <Embodiment 1>

[0046] As Figure 1 shown, the extruder 10 of Embodiment 1 is used for the melt-kneading of resin pellets (resin raw materials) PR. For example, the extruder 10 is used for the production of reinforcing fibers such as tire cords. Here, a tire cord refers to a structure that maintains the shape of a rubber tire of an automobile or the like.

[0047] As Figure 3 and Figure 4As shown, the extruder 10 is a twin-screw extruder having two screws 50. The extruder 10 includes: a kneading processing unit 20 having a cylinder unit CU (a pair of cylinders 21, 22) with a pair of screws 50 disposed therein and supplied with resin pellets PR; and a drive unit 40 that rotates the pair of screws 50.

[0048] <Hopper>

[0049] A hopper 23 is provided in the kneading processing unit 20. The hopper 23 is formed in a substantially cylindrical shape, and granular resin pellets PR are stored inside the hopper 23. The hopper 23 has a pellet inlet 24 and a pellet outlet 25, and the resin pellets PR are introduced into the pellet inlet 24 from a gravimetric feeder FD. It should be noted that the gravimetric feeder FD is provided on an upper floor FL2 or the like, and the upper floor FL2 or the like is provided above a setting floor FL1 on which the extruder 10 is installed.

[0050] The resin pellets PR stored in the hopper 23 descend toward the pellet outlet 25 due to gravity and are supplied from the pellet outlet 25 to the inside of a small block BL1 (a pair of cylinders 21, 22) disposed downstream thereof. Here, as Figure 1 and Figure 2 shown, the side of the kneading processing unit 20 where the hopper 23 is provided, that is, the side for supplying the resin pellets PR before melt-kneading, is the "upstream side". In addition, the side of the extruder 10 where a transfer pipe P is disposed, that is, the side for discharging the molten resin MR after melt-kneading, is the "downstream side".

[0051] <Drive Unit>

[0052] The drive unit 40 includes an electric motor 41 as a drive source and a speed reducer 42 that reduces the rotation of the electric motor 41 and increases the torque. Specifically, the rotational force of the rotating shaft 41a of the electric motor 41 is transmitted to the speed reducer 42, and the rotational force that has been reduced and increased in torque is transmitted from the output shaft 42a of the speed reducer 42 to a pair of screws 50 (a pair of shafts 51) of the kneading processing unit 20 via a gear mechanism or the like (not shown). Thus, the pair of screws 50 rotate in the same direction respectively. However, the pair of screws 50 can also rotate in different directions respectively corresponding to the purpose of the melt-kneading process or the like.

[0053] It should be noted that the rotational speeds of the pair of screws 50 are precisely controlled by controlling the rotational speed of the electric motor 41. In addition, the drive unit 40 including the electric motor 41 and the speed reducer 42 is supported by a base BS fixed to the setting floor FL1. Furthermore, the rotating shaft 41a and the output shaft 42a are parallel to the setting floor FL1.

[0054] <Kneading Processing Unit>

[0055] As Figure 3 andFigure 4 As shown, the kneading processing unit 20 includes a cylinder unit CU. The cylinder unit CU is formed by arranging and integrating a pair (two) of cylinders 21 and 22 in parallel with each other. It should be noted that in Figure 3 and Figure 4 , in order to easily distinguish the pair of cylinders 21 and 22, a double-dot dash line (imaginary line) is drawn between them. Also, the cylinder unit CU is parallel to the installation floor FL1 in the same way as the rotary shaft 41a and the output shaft 42a. In addition, the cylinder unit CU is supported by a pedestal BS fixed to the installation floor FL1.

[0056] The cylinder unit CU includes a total of nine small blocks and large blocks BL1 to BL9. Specifically, the cylinder unit CU is formed by arranging and connecting a total of nine small blocks and large blocks BL1 to BL9 in the axial direction of the rotary shaft 41a and the output shaft 42a.

[0057] The small block BL1 located on the upstream side of the cylinder unit CU, i.e., the hopper 23 side, is an "inlet side block" for supplying resin particles PR into the interior of the cylinder unit CU. A supply port 26 is provided on the small block BL1, and the supply port 26 opens in a direction perpendicular to the installation floor FL1 and faces the particle discharge port 25 of the hopper 23. Thus, the resin particles PR stored in the hopper 23 are supplied into the interior of the pair of cylinders 21 and 22 via the particle discharge port 25 and the supply port 26.

[0058] In addition, the small block BL9 located on the downstream side of the cylinder unit CU, i.e., the transfer pipe P side, is an "outlet side block" for discharging the molten resin MR generated after melting and kneading the resin particles PR to the outside of the cylinder unit CU. Specifically, a molten resin discharge port (discharge port) 27 for discharging the molten resin MR to the outside is provided inside the small block BL9 (inside the pair of cylinders 21 and 22). And, on the more downstream side ( Figure 1 on the right side) of the molten resin discharge port 27, a transfer pipe P for transferring the molten resin MR to the next process is arranged. Thus, the molten resin MR is supplied to a processing device (not shown) of the next process by means of the transfer pipe P.

[0059] In addition, a small block BL2 is connected to the downstream side of the small block BL1, and a pair of small transfer passages TP1 (see Figure 2 and Figure 3 ) are provided inside the small block BL2 (inside the pair of cylinders 21 and 22). And, a heater HT is installed on the outer peripheral portion of the small block BL2. Thus, the resin particles PR passing through the pair of small transfer passages TP1 of the small block BL2 are melted by the heater HT.

[0060] In addition, a pair of small blocks BL7 and BL8, which have the same shape and structure as the small block BL2, are arranged on the upstream side of the small block BL9. That is to say, a pair of small transfer passages TP1 are respectively provided inside the small blocks BL7 and BL8 (inside the pair of cylinder blocks 21 and 22). In addition, heaters HT are respectively installed on the outer peripheral parts of the small blocks BL7 and BL8. Thus, the molten resin MR passing through the small blocks BL7 and BL8 reaches the small block BL9 in a molten state without solidifying.

[0061] In addition, in the longitudinal direction of the cylinder block unit CU, a total of 4 large blocks BL3 to BL6, which are larger than the small blocks BL2, BL7, and BL8, are arranged between the small block BL2 and the small block BL7. And a pair of large transfer passages TP2 (see Figure 2 and Figure 4 ) are respectively provided inside the large blocks BL3 to BL6 (inside the pair of cylinder blocks 21 and 22).

[0062] Moreover, heaters HT are also respectively installed on the outer peripheral parts of the large blocks BL3 to BL6. Thus, the resin particles PR passing through the large blocks BL3 to BL6 are kneaded while becoming the molten resin MR. It should be noted that the resin particles PR are heated not only by the heater HT but also by the heat generated by the shearing action accompanied by the rotation of the pair of screws 50.

[0063] Here, as shown by the arrow M1 in Figure 1 , the resin particles PR input from the gravimetric feeder FD into the hopper 23 are supplied from the hopper 23 to the inside of the small block BL1 as the inlet side block. Then, as shown by the arrow M2 in Figure 1 , the resin particles PR supplied to the inside of the pair of cylinder blocks 21 and 22, that is, the inside of the pair of small transfer passages TP1 and the large transfer passages TP2, are kneaded while becoming the molten resin MR as they accompany the rotation of the pair of screws 50, and are conveyed to the downstream side of the cylinder block unit CU. And finally, as shown by the arrow M3 in Figure 1 , the molten resin MR is conveyed from the molten resin discharge port 27 of the small block BL9 as the outlet side block to the transfer pipe P.

[0064] In addition, as shown in Figure 3 and Figure 4 , the inner diameter dimension d1 of the small transfer passage TP1 of the small blocks BL2, BL7, and BL8 is smaller than the inner diameter dimension d2 of the large transfer passage TP2 of the large blocks BL3 to BL6 (d1 < d2). That is, see Figure 2, the cross-sectional areas of the cylinder blocks 21 and 22 that are orthogonal to the direction from the supply region AR1 toward the kneading region AR2 are larger in one region than in other regions. Specifically, the cross-sectional area S2 inside the kneading region AR2 is larger than the cross-sectional area S1 inside the supply region AR1 (S2 > S1).

[0065] Therefore, as Figure 1 and Figure 2 shown, a relatively large level difference is formed between the small block BL2 and the large block BL3 and between the large block BL6 and the small block BL7. This level difference hinders the smooth conveyance of the resin raw materials (resin particles PR, molten resin MR). Therefore, conversion adapters 28 and 29 are provided between the small block BL2 and the large block BL3 and between the large block BL6 and the small block BL7, which gradually change the inner diameter size to gently connect the small conveyance passage TP1 and the large conveyance passage TP2.

[0066] Specifically, the inner diameter size of the conversion adapter 28 between the small block BL2 and the large block BL3 gradually increases from the upstream side toward the downstream side. On the other hand, the inner diameter size of the conversion adapter 29 between the large block BL6 and the small block BL7 gradually decreases from the upstream side toward the downstream side.

[0067] And, as Figures 2 - 4 shown, inside the small conveyance passage TP1 and the large conveyance passage TP2 respectively provided in the pair of cylinder blocks 21 and 22, screws 50 are rotatably accommodated respectively. Hereinafter, the structures of the small conveyance passage TP1, the large conveyance passage TP2, and the screws 50 accommodated inside these passages will be described in detail.

[0068] <Small conveyance passage>

[0069] As Figure 3 shown, in the small blocks BL2, BL7, and BL8, the small conveyance passages TP1 of one cylinder block 21 and the small conveyance passages TP1 of the other cylinder block 22 are arranged in parallel with each other and communicate with each other inside. And, the distance L between the centers c1 of the respective small conveyance passages TP1 is smaller than the inner diameter size d1 of the small conveyance passage TP1 (L < d1). Thus, when observing the pair of small conveyance passages TP1 from the axial direction of the screw 50, the opposed portions of the pair of small conveyance passages TP1 partially overlap with each other and communicate with each other at the overlapping portion.

[0070] <Large conveyance passage>

[0071] As Figure 4As shown, in the large blocks BL3 to BL6, the large transfer passages TP2 of one cylinder block 21 and the large transfer passages TP2 of another cylinder block 22 are arranged in parallel with each other, and their interiors are connected to each other. Moreover, the distance L between the centers c2 of the large transfer passages TP2 is less than the inner diameter dimension d2 of the large transfer passages TP2 (L < d2). Thus, when observing a pair of large transfer passages TP2 from the axial direction of the screw 50, the opposing portions of the pair of large transfer passages TP2 partially overlap each other, and communicate with each other at the overlapping portion. It should be noted that the inner diameter dimension d2 of the large transfer passage TP2 is larger than the inner diameter dimension d1 of the small transfer passage TP1 (d2 > d1).

[0072] In addition, as Figure 3 and Figure 4 shown, when observing the small transfer passage TP1 and the large transfer passage TP2 from the axial direction of the screw 50 respectively, the center c2 of the large transfer passage TP2 is offset by a distance t1 (≒ L / 7) from the center c1 of the small transfer passage TP1 to the opposite side (the upper side in the figure) opposite to the side where the installation floor FL1 is located.

[0073] <Screw>

[0074] A pair of screws 50 have the same shape. And a pair of screws 50 are respectively arranged inside a pair of cylinder blocks 21, 22 (small transfer passages TP1, large transfer passages TP2). A pair of screws 50 have the function of kneading and transferring the resin raw materials (resin particles PR, molten resin MR) existing in the small transfer passages TP1 and the large transfer passages TP2 of the pair of cylinder blocks 21, 22 from the upstream side to the downstream side. It should be noted that the distance L between the rotation centers c3 of the pair of screws 50 is the same as the distance L between the center c1 of the small transfer passage TP1 and the distance L between the centers c2 of the large transfer passages TP2.

[0075] As Figure 3 and Figure 4 shown, the outer diameter dimension (dotted line in the figure) of the screw 50 is the same outer diameter dimension d3 throughout the entire length direction of the screw 50. And the distance L between the rotation centers c3 of the pair of screws 50 is less than the outer diameter dimension d3 of the screw 50 (L < d3). Thus, when observing a pair of screws 50 from the axial direction, the opposing portions of the pair of screws 50 mesh with each other. However, a pair of screws 50 can rotate smoothly without interfering with each other.

[0076] And, as Figure 3As shown, a minute gap CL (= (d1 - d3) / 2) is provided within the entire circumference of the screw 50 between the screw 50 and the small transfer passage TP1. This minute gap CL is about a few millimeters in size such that even when the screw 50 is under a large load (lateral force) during the operation of the extruder 10, the screw 50 does not contact the small transfer passage TP1. Thus, the resin raw materials (resin particles PR, molten resin MR) present in the small transfer passage TP1 can be efficiently transferred downstream along with the rotation of the screw 50. In addition, uneven wear of the screw 50 caused by contact between the screw 50 and the small transfer passage TP1 can be suppressed.

[0077] In addition, as Figure 4 shown, when observing a pair of screws 50 from the axial direction, the rotation center c3 of the screw 50 is offset by a distance t1 toward the side of the installation floor FL1 (lower side in the figure) with respect to the center c2 of the large transfer passage TP2. Specifically, the rotation centers c3 of the pair of screws 50 are respectively offset toward the lower walls 21a, 22a of the large transfer passage TP2 that form the pair of cylinders 21, 22.

[0078] In addition, a lower gap CL1 is provided between the screw 50 and the lower walls 21a, 22a that form the large transfer passage TP2. In contrast, an upper gap CL2 is provided between the screw 50 and the upper walls 21b, 22b that form the large transfer passage TP2, and the upper walls 21b, 22b are located on the opposite side of the side where the lower walls 21a, 22a are provided. And the upper gap CL2 is larger than the lower gap CL1 (CL2 > CL1).

[0079] Here, the size of the lower gap CL1 is substantially the same as the minute gap CL of the small transfer passage TP1 (see Figure 3 ). In addition, the size of the upper gap CL2 is approximately 9 times that of the lower gap CL1 (CL2 ≒ 9 × CL1). Thus, it is possible to suppress the resin raw materials (resin particles PR, molten resin MR) from staying for a long time on the side of the installation floor FL1 of the large transfer passage TP2, i.e., the lower side in the direction of gravity.

[0080] It should be noted that due to the centrifugal force and the like generated when the screw 50 rotates, the molten resin MR bulges out and overflows into the part of the upper gap CL2 of the large transfer passage TP2. Thus, the transfer speed of the molten resin MR inside the large transfer passage TP2 toward the downstream side can be slowed down. Thus, the residence time (reaction time) of the molten resin MR inside the large transfer passage TP2 can be extended, and the processing capacity can be improved.

[0081] In addition, as Figure 2As shown, a long shaft 51 made of solid round steel bar is provided at the rotation center of the screw 50. A plurality of screw elements are installed on the shaft 51 so as not to rotate relative to each other. Specifically, the forward feed screw fins 52 (see Figure 5A and Figure 5B ) and the forward feed kneading part 53 (see Figure 6A and Figure 6B ) are respectively installed on the shaft 51. The forward feed screw fins 52 and the forward feed kneading part 53 have the function of kneading and transporting the resin raw materials (resin particles PR, molten resin MR) from the upstream side to the downstream side along with the rotation of the rotating shaft 41a of the electric motor 41 in one direction.

[0082] It should be noted that the number and arrangement order of the forward feed screw fins 52 and the forward feed kneading part 53 installed on the shaft 51 can be arbitrarily set according to the specifications required by the extruder 10 (such as the purpose of the melt-kneading process, etc.).

[0083] <Forward Feed Screw Fins>

[0084] The forward feed screw fins 52 form the conveying part of the screw 50 and form the shapes shown in Figure 5A and Figure 5B . Specifically, the forward feed screw fins 52 are formed in a right-handed thread shape with spiral thread teeth 52a so that when the rotation direction of the shaft 51 (see Figure 2 ) is set to the clockwise direction of the arrow CW in the figure, the resin raw materials (resin particles PR, molten resin MR) move in the direction of the arrow F (forward direction) in the figure.

[0085] In addition, a fixing hole 52b for inserting the shaft 51 is provided at the rotation center of the forward feed screw fins 52. The shaft 51 and the fixing hole 52b are serrated and engaged with each other in order to transmit a large torque. The main function of the forward feed screw fins 52 is to convey the resin raw materials (resin particles PR, molten resin MR) inside the pair of cylinders 21 and 22.

[0086] <Forward Feed Kneading Part>

[0087] On the other hand, the forward feed kneading part 53 forms the kneading part of the screw 50 and forms the shapes shown in Figure 6A and Figure 6B . Specifically, the forward feed kneading part 53 is formed in a shape in which a plurality of angular parts 53a are arranged in a spiral shape so that when the rotation direction of the shaft 51 is set to the clockwise direction of the arrow CW in the figure, the resin raw materials (resin particles PR, molten resin MR) are kneaded and conveyed in the direction of the arrow F (forward direction) in the figure.

[0088] In addition, a fixing hole 53b for inserting the shaft 51 is provided at the rotation center of the forward feed kneading section 53. The shaft 51 is also serrated and engaged with the fixing hole 53b in order to transmit a large torque. The main function of the forward feed kneading section 53 is to knead the resin raw materials (resin particles PR, molten resin MR) inside the pair of cylinders 21 and 22.

[0089] <Supply Area>

[0090] As Figure 2 shown, a supply area (first area) AR1 for supplying the resin particles PR supplied to the inside of the pair of cylinders 21 and 22 to the downstream side of the cylinder unit CU is provided on the upstream side of the cylinder unit CU, i.e., the hopper 23 side. That is, the pair of cylinders 21 and 22 includes the supply area AR1, and a hopper 23 for introducing the resin particles PR into the pair of cylinders 21 and 22 is provided in the supply area AR1. Specifically, the supply area AR1 is formed by the small block BL2 and the small block BL1 as the inlet side block. In addition, the screw 50 located in the supply area AR1 includes a total of four forward feed spiral fins 52.

[0091] Thus, the resin particles PR supplied to the inside of the pair of cylinders 21 and 22 (small transfer passage TP1) are conveyed from the supply area AR1 to the kneading area AR2 along with the rotation of the pair of screws 50. At this time, since the heater HT is only provided on the small block BL2, the resin particles PR are not completely melted. In other words, in the supply area AR1, the resin particles PR are softened (become soft).

[0092] And, the resin particles PR that have passed through the supply area AR1 through the rotation of the pair of screws 50 smoothly reach the kneading area AR2 via the conversion adapter 28.

[0093] <Kneading Area>

[0094] A kneading area (second area) AR2 for kneading while melting the resin particles PR and conveying the kneaded molten resin MR to the downstream side of the cylinder unit CU is provided on the downstream side of the supply area AR1. That is, the pair of cylinders 21 and 22 includes the kneading area AR2, and the kneading area AR2 occupies approximately half of the cylinder unit CU. Specifically, the kneading area AR2 is formed by a total of four large blocks BL3 to BL6. In addition, the screw 50 located in the kneading area AR2 includes three groups connecting six forward feed kneading sections 53 and three forward feed spiral fins 52.

[0095] Thus, the resin particles PR supplied from the supply region AR1 are kneaded while being melted inside the kneading region AR2 (large transfer path TP2) as the pair of screws 50 rotates. At this time, since the heaters HT are installed on all of the large blocks BL3 to BL6, the resin particles PR can be reliably melted. In addition, since more than half of the screw elements within the range of the kneading region AR2 are forward feed kneading portions 53, the molten resin MR can be sufficiently kneaded.

[0096] In addition, the molten resin MR melted and kneaded in the kneading region AR2 bulges due to the action of centrifugal force or the like accompanying the rotation of the pair of screws 50 and overflows to a portion of the upper gap CL2 (see Figure 4 ) formed on the upper wall 21b, 22b side, and the upper walls 21b, 22b form the inside of the large transfer path TP2. As a result, the transfer speed of the molten resin MR inside the large transfer path TP2 toward the downstream side becomes slower. As a result, the residence time of the molten resin MR inside the large transfer path TP2 becomes longer, and the processing capacity is improved.

[0097] <Measurement region>

[0098] Adjacent to the downstream side of the kneading region AR2 via the conversion adapter 29, there is provided a measurement region (third region) AR3 for homogenizing the molten resin MR that has been melted and kneaded. In this way, the pair of cylinders 21, 22 includes the measurement region AR3. It should be noted that the measurement region AR3 is formed by two small blocks BL7, BL8, and the cross-sectional area S1 inside the measurement region AR3 (small transfer path TP1) is the same as the cross-sectional area S1 inside the supply region AR1 (small transfer path TP1) (see Figure 3 ). That is, with respect to the cross-sectional area of the cylinders 21, 22 orthogonal to the direction from the supply region AR1 toward the kneading region AR2, the cross-sectional area S2 inside the kneading region AR2 (large transfer path TP2) is larger than the cross-sectional area S1 inside the supply region AR1 (small transfer path TP1) and the measurement region AR3 (small transfer path TP1). In addition, the screw 50 located within the measurement region AR3 includes a total of five forward feed spiral fins 52.

[0099] Thus, the molten resin MR supplied from the kneading region AR2 is transported in a molten state toward the downstream side of the measurement region AR3 as the pair of screws 50 rotates. At this time, since the heaters HT are installed on both of the small blocks BL7, BL8, the molten state of the molten resin MR can be reliably maintained. As a result, the homogenized molten resin MR reaches the small block BL9 serving as the outlet side block in a stable state without pulsation or the like.

[0100] <Discharge region>

[0101] On the downstream side of the metering region AR3, a discharge region AR4 formed by a small block BL9 (exit-side block) is provided. In this way, the pair of cylinders 21, 22 includes the discharge region AR4. And the molten resin MR supplied to the discharge region AR4 by the rotation of the pair of screws 50 is discharged to the outside of the cylinder unit CU via the molten resin discharge port 27. That is to say, the molten resin discharge port 27 for discharging the kneaded molten resin MR is connected to the kneading region AR2 via the metering region AR3 and the discharge region AR4. Then, the molten resin MR reaches the processing device (not shown) of the next process through the transfer pipe P.

[0102] <Comparison of the processing capabilities of Embodiment 1 and the comparative example>

[0103] Next, in the structure of the extruder 10 of Embodiment 1, that is, the cross-sectional area S2 of the large transfer passage TP2 in the kneading region AR2 is larger than the cross-sectional area S1 of the small transfer passages TP1 in the supply region AR1 and the metering region AR3 (S2 > S1), the residence time of the resin raw materials (resin pellets PR, molten resin MR) passing through the inside of the cylinder unit CU was measured, and an investigation of the processing capacity was carried out. The results are shown in Figure 7 .

[0104] It should be noted that for the numerical values such as the dimensions of the extruder 10 of Embodiment 1, refer to Figure 4 , the outer diameter dimension d3 of the screw 50 was set to "47 mm", the inner diameter dimension d2 of the large transfer passage TP2 of the large blocks BL3 - BL6 was set to "69 mm", and furthermore, the offset amount (distance t1) of the rotation center c3 of the screw 50 relative to the center c2 of the large transfer passage TP2 toward the installation floor FL1 side (downward in the figure) was set to "11 mm".

[0105] In addition, the number and arrangement of the other small blocks BL1, BL2, BL7 - BL9, the number and arrangement of the large blocks BL3 - BL6, and the structure of the screw 50 (the type, number, and arrangement of the screw elements) are the same as those of the structure shown in Figure 2 .

[0106] In addition, the resin raw materials (resin pellets PR, molten resin MR) used in the measurement were polypropylene with an MFR (melt flow rate) of "10" and a raw material mixed with a small amount of carbon black masterbatch for easy measurement of the residence time. And a timer was started at the moment when the masterbatch was supplied to the cylinder unit CU, and the timer was stopped at the moment when the black molten resin MR was discharged from the molten resin discharge port 27. Thus, the residence time, that is, the time for the resin raw materials to pass through the inside of the cylinder unit CU, was measured.

[0107] As a result, in Embodiment 1, when the rotational speed of a pair of screws 50 was set to "150 rpm", the discharge amount of the resin raw material per unit time was set to "100 kg / h", and multiple measurements were performed under the same conditions, the average residence time was "125 sec". In addition, when the rotational speed of a pair of screws 50 was set to twice that, "300 rpm", and the discharge amount of the resin raw material per unit time was set to "200 kg / h", and multiple measurements were performed under the same conditions, the average residence time was "62 sec".

[0108] In contrast, in the comparative example, an extruder (not shown) having the same shape as the extruder 10 of Embodiment 1 and a small transfer passage TP1 having a cross-sectional area S1 over the entire range of the cylinder unit CU was used. That is, the extruder of the comparative example was not provided with the large transfer passage TP2 (large blocks BL3 to BL6).

[0109] As a result, in the comparative example, when the rotational speed of a pair of screws 50 was set to "150 rpm" so as to achieve the same operating conditions as in Embodiment 1, the discharge amount of the resin raw material per unit time was set to "100 kg / h", and multiple measurements were performed under the same conditions, the average residence time was "40 sec". In addition, when the rotational speed of a pair of screws 50 was set to twice that, "300 rpm", and the discharge amount of the resin raw material per unit time was set to "200 kg / h", and multiple measurements were performed under the same conditions as in Embodiment 1, the average residence time was "19 sec".

[0110] In this way, in Embodiment 1, compared with the comparative example, it was confirmed that the residence time of the resin raw material (resin particles PR, molten resin MR) inside the cylinder unit CU could be made approximately "3 times" longer. Thus, without increasing the size of the extruder 10, that is, without making the pair of cylinders 21, 22 and the screws 50 longer or making the pair of cylinders 21, 22 and the screws 50 larger in diameter and in a state where the discharge amount of the resin raw material per unit time was the same, the residence time of the resin raw material could be extended. Thus, in the extruder 10 of Embodiment 1, it was possible to easily handle resin raw materials that required an extended residence time and improve the processing capacity.

[0111] Here, the inner diameter size d2 of the large transfer passage TP2 was not made too large relative to the outer diameter size d3 of the screw 50. Specifically, it was desirable that the inner diameter size d2 of the large transfer passage TP2 be "2 to 3 times" the size of the outer diameter size d3 of the screw 50. If it was set to a larger size (for example, 10 times, etc.), the resin raw material (resin particles PR, molten resin MR) would be difficult to flow inside the cylinder unit CU, and the resin raw material would stay in the upper gap CL2 of the large transfer passage TP2 (see Figure 4The part that does not get discharged. As a result, maintenance operations for removing the resin raw material remaining in the upper gap CL2 need to be frequently performed, etc.

[0112] As described in detail above, in the extruder 10 according to Embodiment 1, in terms of the cross-sectional areas inside the pair of cylinders 21 and 22 in the direction orthogonal to the direction from the supply region AR1 toward the kneading region AR2, the kneading region AR2 (cross-sectional area S2) is larger than the supply region AR1 (cross-sectional area S1) (S2 > S1).

[0113] Thereby, it is possible to extend the residence time of the resin raw material (resin particles PR, molten resin MR) without increasing the size of the extruder 10, that is, without increasing the length of the pair of cylinders 21 and 22 and the screw 20 or increasing the diameter of the pair of cylinders 21 and 22 and the screw 50, and improve the processing capacity. Thereby, it is possible to easily handle resin raw materials that require an extended residence time, and furthermore, the extruder 10 can be used for a wide range of melt-kneading applications.

[0114] <Embodiment 2>

[0115] As Figure 8 shown, the extruder 60 according to Embodiment 2 is different from the extruder 10 according to Embodiment 1 (see Figure 2 ) only in that it does not have a metering region AR3. Accordingly, in the extruder 60 of Embodiment 2, the range of the kneading region AR2 becomes longer.

[0116] Specifically, in the extruder 60 of Embodiment 2, instead of the small blocks BL7 and BL8 that form the metering region AR3 of the extruder 10 according to Embodiment 1, large blocks BL10 and BL11 are used and the conversion adapter 29 is omitted (see Figure 2 ). That is, the small blocks BL1, BL2, the large blocks BL3 to BL6, BL10, BL11, and the small block BL9 are arranged in this order from the upstream side to the downstream side of the cylinder unit CU.

[0117] It should be noted that the shapes and structures of the newly added large blocks BL10 and BL11 are the same as those of the large blocks BL3 to BL6.

[0118] In the extruder 60 of Embodiment 2 formed in the above manner, it is also possible to achieve substantially the same effects as the extruder 10 of the above-described Embodiment 1. In addition, in the extruder 60 of Embodiment 2, since the range of the kneading region AR2 can be extended, the residence time of the resin raw material (resin particles PR, molten resin MR) can be further extended, and the processing capacity can be further improved.

[0119] It should be noted that in Figure 8In this case, a total of five forward feed screw fins 52 are arranged on the downstream side of the pair of screws 50. However, depending on the purpose of the melt-kneading process or the like, a part or all of the total of five forward feed screw fins 52 can be changed to a forward feed kneading section 53.

[0120] <Embodiment 3>

[0121] As Figure 9 shown, the extruder 70 of Embodiment 3 differs from the extruder 10 of Embodiment 1 (see Figure 2 ) only in the shape of a part of the screw elements that form the pair of screws 50.

[0122] Specifically, a reverse feed screw fin 71 and a reverse feed kneading section 72 are arranged in a portion disposed on the downstream side of the kneading region AR2 of the pair of screws 50. That is, the kneading section located in the kneading region AR2 also includes a reverse feed kneading section. Further, in the longitudinal direction of the cylinder unit CU, a pair of reverse feed screw fins 71 and six reverse feed kneading sections 72 are provided within the range of the large blocks BL5, BL6, and the conversion adapter 29. In the region RSA where these reverse feed screw fins 71 and reverse feed kneading sections 72 are arranged, the six reverse feed kneading sections 72 are arranged so as to be sandwiched by the pair of reverse feed screw fins 71.

[0123] <Reverse Feed Screw Fin>

[0124] As Figure 10A and Figure 10B shown, the shape of the reverse feed screw fin 71 is similar to the shape of the forward feed screw fin 52 of Embodiment 1 (see Figure 5A and Figure 5B ). While the forward feed screw fin 52 transports the resin raw material (resin particles PR, molten resin MR) in the forward direction (the direction from the upstream side to the downstream side), the reverse feed screw fin 71 transports the resin raw material in the reverse direction (the direction from the downstream side to the upstream side).

[0125] Specifically, the reverse feed screw fin 71 is formed in a reverse thread shape having a spiral thread tooth 71a so that when the rotation direction of the shaft 51 (see Figure 2 ) is the clockwise direction of the arrow CW in the figure, the resin raw material moves in the direction of the arrow R (reverse direction) in the figure. Further, a fixing hole 71b for inserting the shaft 51 is provided at the rotation center of the reverse feed screw fin 71, and the shaft 51 is serratedly engaged with the fixing hole 71b.

[0126] <Reverse Feed Kneading Section>

[0127] As Figure 11A and Figure 11BAs shown, the shape of the reverse-feed kneading section 72 is similar to that of the forward-feed kneading section 53 of the first embodiment (see Figure 6A and Figure 6B ). While the forward-feed kneading section 53 conveys the resin raw material (resin particles PR, molten resin MR) in the forward direction (from the upstream side to the downstream side) while kneading, the reverse-feed kneading section 72 conveys the resin raw material in the reverse direction (from the downstream side to the upstream side) while kneading.

[0128] Specifically, it is formed in a shape in which a plurality of angular portions 72a are arranged in a spiral shape so that when the rotation direction of the shaft 51 is the clockwise direction of the arrow CW in the figure, the resin raw material is conveyed in the direction of the arrow R (reverse direction) in the figure while being kneaded. In addition, a fixing hole 72b for inserting the shaft 51 is provided at the rotation center of the reverse-feed kneading section 72, and the shaft 51 is serratedly engaged with the fixing hole 72b.

[0129] In the extruder 70 of the third embodiment formed in the above manner, the same effects as those of the extruder 10 of the first embodiment described above can also be achieved. In addition, in the extruder 70 of the third embodiment, the portion of the pair of screws 50 on the downstream side of the kneading region AR2 includes a reverse-feed screw blade 71 for conveying the resin raw material (resin particles PR, molten resin MR) in the reverse direction opposite to the forward direction from the supply region AR1 to the kneading region AR2 and a reverse-feed kneading section 72. Therefore, the residence time of the resin raw material in the kneading region AR2 can be further extended, and the processing capacity can be further improved.

[0130] It should be noted that in Figure 9 , both the reverse-feed screw blade 71 and the reverse-feed kneading section 72 are arranged, but depending on the purpose of the melt-kneading process, etc., for example, the reverse-feed screw blade 71 can be omitted and only the reverse-feed kneading section 72 can be provided.

[0131] In addition, in order to finely adjust the residence time of the resin raw material in the kneading region AR2, for example, a neutral kneading section (not shown) can be used instead of the reverse-feed kneading section 72 in Figure 9 . Here, the neutral kneading section is a structure that only kneads the resin raw material and does not perform forward feeding or reverse feeding. That is, the neutral kneading section is not a kneading section with conveying ability.

[0132] <Embodiment 4>

[0133] As Figure 12 shown, the extruder 80 of the fourth embodiment is the same as the extruder 10 of the first embodiment (see Figure 4)Compared with [reference], the difference is only that the lower gap CL1 is reduced until it almost disappears and the shape of the large transfer path TP2 of the pair of cylinder blocks 21, 22 forming the large blocks BL3 - BL6 is changed.

[0134] Specifically, the rotation center c3 of the pair of screws 50 is offset by a distance t2 (t2 > t1) from the center c2 of the pair of cylinder blocks 21, 22 (the pair of large transfer paths TP2) toward the lower walls 21a, 22a of the pair of cylinder blocks 21, 22, thereby setting the lower gap CL1 to "substantially zero".

[0135] In addition, a convex portion 81 that enters between the pair of adjacent screws 50 is provided between the lower walls 21a, 22a of the large transfer path TP2 forming the large blocks BL3 - BL6. And arc portions 82 along the outer shape of the screws 50 are provided at the portions (a total of two portions) of the convex portion 81 facing the pair of screws 50. It should be noted that the radius dimension of the arc portion 82 is substantially the same as the radius dimension of the outer diameter of the screw 50.

[0136] In the extruder 80 of Embodiment 4 formed in the above manner, the same effects as those of the extruder 10 of Embodiment 1 described above can also be achieved. In addition, in the extruder 80 of Embodiment 4, the convex portion 81 having the pair of arc portions 82 can support the opposing portions of the pair of screws 50, so that even when a large load (lateral force) is applied to the pair of screws 50, the situation where the pair of screws 50 approach each other and interfere can be prevented.

[0137] <Embodiment 5>

[0138] As Figure 13 shown, the extruder 90 of Embodiment 5 is different from the extruder 10 of Embodiment 1 (see Figure 4 ) only in that when observing the kneading region AR2 (see Figure 2 ) from the axial direction of the pair of screws 50, the rotation center c3 of the pair of screws 50 coincides with the center c2 of the pair of cylinder blocks 21, 22 (the pair of large transfer paths TP2). Thus, a relatively large gap CL3 (= (d2 - d3) / 2) is formed over the entire circumference of the screws 50 between the screws 50 and the large transfer path TP2.

[0139] In the extruder 90 of Embodiment 5 formed in the above manner, the same effects as those of the extruder 10 of Embodiment 1 described above can also be achieved. In addition, in the extruder 90 of Embodiment 5, since a relatively large gap CL3 is formed in the range of the kneading region AR2 and over the entire circumference of the pair of screws 50, even when a large load (lateral force) is applied to the pair of screws 50, interference between each of the pair of screws 50 and the large transfer path TP2 can be reliably prevented.

[0140] <Embodiment 6>

[0141] As Figure 14 shown, the extruder 100 of Embodiment 6 is different from the extruder 10 of Embodiment 1 (see Figure 4 ) in that, similar to Embodiment 4 (see Figure 12 ), the lower clearance CL1 is reduced so that the lower clearance CL1 almost disappears, and a lower straight portion (straight portion) 101 and an upper straight portion (straight portion) 102 are provided between a pair of adjacent cylinders 21 and 22.

[0142] That is, the lower straight portion 101 is arranged on the side of the lower walls 21a and 22a, and the upper straight portion 102 is arranged on the side of the upper walls 21b and 22b. More specifically, the lower straight portion 101 and the upper straight portion 102 are straight portions that tangentially connect the arc-shaped inner wall W1 forming one cylinder 21 and the arc-shaped inner wall W2 forming the other cylinder 22. Thus, as Figure 14 shown, the cross-sectional shape of the pair of large conveying passages TP2 is substantially elliptical.

[0143] In the extruder 100 of Embodiment 6 formed in the above manner, substantially the same effects as those of the extruder 10 of the above Embodiment 1 can also be exhibited. In addition, in the extruder 100 of Embodiment 6, since there is no convex portion protruding between the pair of screws 50, the cross-sectional area inside the kneading region AR2 (the pair of large conveying passages TP2) can be further increased, the residence time of the resin raw material (resin particles PR, molten resin MR) can be further extended, and the processing capacity can be further improved.

[0144] <Embodiment 7>

[0145] As Figure 15 shown, the extruder 110 of Embodiment 7 is different from the extruder 80 of Embodiment 4 (see Figure 12 ) in that side wall portions 21c and 22c capable of supporting the pair of screws 50 on the opposite side (left and right sides in the figure) to the opposed side are provided in a pair of adjacent cylinders 21 and 22. In addition, the cross-sectional shape of the pair of large conveying passages TP2 is different in that the pair of screws 50 are moved upward by a distance t3 (t3 > t2) toward the upper walls 21b and 22b and the pair of screws 50 can rotate relative to each other in this state.

[0146] Thereby, a larger upper clearance CL4 (CL4 > CL2) can be ensured. In addition, the clearance between the pair of screws 50 and the side wall portions 21c and 22c is "substantially zero".

[0147] In the extruder 110 of Embodiment 7 formed in the above manner, substantially the same effects as those of the extruder 80 of Embodiment 4 described above can also be achieved. In addition, in the extruder 110 of Embodiment 7, since the pair of cylinders 21, 22 are provided with side wall portions 21c, 22c on the opposite side to the opposed side that can support the adjacent screw 50, it is possible to suppress the pair of screws 50 from swinging in the directions of approaching and separating from each other inside the pair of large conveyance passages TP2.

[0148] <Embodiment 8>

[0149] As Figure 16 shown, the extruder 120 of Embodiment 8 is different from the extruder 110 of Embodiment 7 (see Figure 15 ) in that, similar to Embodiment 6 (see Figure 14 ), an upper straight portion (straight portion) 102 is provided between the pair of adjacent cylinders 21, 22.

[0150] Specifically, the upper straight portion 102 is a straight portion provided on the upper walls 21b, 22b forming the pair of cylinders 21, 22 and tangentially connecting the arc-shaped inner wall W1 forming one cylinder 21 and the arc-shaped inner wall W2 forming the other cylinder 22 to each other.

[0151] In the extruder 120 of Embodiment 8 formed in the above manner, substantially the same effects as those of the extruder 110 of Embodiment 7 described above can also be achieved. In addition, in the extruder 120 of Embodiment 8, there are no convex portions on the upper walls 21b, 22b, and instead, an upper straight portion 102 is provided. Therefore, it is possible to further increase the cross-sectional area inside the kneading region AR2 (the pair of large conveyance passages TP2), further extend the residence time of the resin raw material (resin particles PR, molten resin MR), and further improve the processing capacity.

[0152] <Embodiment 9>

[0153] As Figure 17 shown, the extruder 130 of Embodiment 9 is different from the extruder 120 of Embodiment 8 (see Figure 16 ) only in that the convex portions 81 of the lower walls 21a, 22a are omitted and a lower straight portion 101 is provided similar to Embodiment 6 (see Figure 14 ).

[0154] Specifically, the lower straight portion 101 is a straight portion provided on the lower walls 21a, 22a forming the pair of cylinders 21, 22 and tangentially connecting the arc-shaped inner wall W1 forming one cylinder 21 and the arc-shaped inner wall W2 forming the other cylinder 22 to each other.

[0155] In the extruder 130 of Embodiment 9 formed in the above manner, substantially the same effects as those of the extruder 120 of Embodiment 8 described above can also be achieved. In addition, in the extruder 130 of Embodiment 9, since there are no convex portions on the lower walls 21a and 22a and instead there are lower straight portions 101, the cross-sectional area inside the kneading region AR2 (pair of large transfer passages TP2) can be further increased, the residence time of the resin raw material (resin particles PR, molten resin MR) can be further extended, and the processing capacity can be improved.

[0156] <Embodiment 10>

[0157] As Figure 18 shown, the extruder 140 of Embodiment 10 is different from the extruder 10 of Embodiment 1 (see Figure 2 ) only in that the shape inside the pair of cylinders 21 and 22 is rectangular. Specifically, when observing the kneading region AR2 (pair of large transfer passages TP2) from the axial direction of the pair of screws 50, the shape formed by docking the pair of large transfer passages TP2 inside the pair of cylinders 21 and 22 is substantially rectangular. It should be noted that sufficient gaps are ensured around the pair of screws 50.

[0158] In the extruder 140 of Embodiment 10 formed in the above manner, substantially the same effects as those of the extruder 10 of Embodiment 1 described above can also be achieved. In addition, in the extruder 140 of Embodiment 10, since the shape inside the pair of cylinders 21 and 22 is rectangular, the pair of cylinders 21 and 22 can be easily formed by stamping a steel plate having a thickness, etc.

[0159] <Embodiment 11>

[0160] As Figure 19 shown, the extruder 150 of Embodiment 11 is different from the extruder 140 of Embodiment 10 (see Figure 18 ) in that arc-shaped connecting portions 151 having a specified radius are integrally provided at the corners (a total of 4 portions) inside the pair of cylinders 21 and 22.

[0161] In the extruder 150 of Embodiment 11 formed in the above manner, substantially the same effects as those of the extruder 140 of Embodiment 10 described above can also be achieved. In addition, in the extruder 150 of Embodiment 11, since arc-shaped connecting portions 151 are integrally provided at the corners inside the pair of cylinders 21 and 22, stress concentration at the corners inside the pair of cylinders 21 and 22 can be suppressed. As a result, cracks, etc. entering the corners inside the pair of cylinders 21 and 22 can be effectively suppressed.

[0162] <Embodiment 12>

[0163] As Figure 20 shown, compared with the extruder 140 of Embodiment 10 (see Figure 18 ), the extruder 160 of Embodiment 12, like Embodiment 4 (see Figure 12 ), has convex portions 81 that enter between a pair of adjacent screws 50 provided on the lower walls 21a, 22a inside the pair of cylinders 21, 22 (inside the pair of large transfer passages TP2). It should be noted that the radius size of the pair of arc portions 82 forming the convex portion 81 is approximately the same as the radius size of the outer diameter of the screw 50.

[0164] In the extruder 160 of Embodiment 12 formed in the above manner, it is also possible to exhibit substantially the same effects as the extruder 80 of the above-described Embodiment 4.

[0165] <Embodiment 13>

[0166] As Figure 21 shown, compared with the extruder 160 of Embodiment 12 (see Figure 20 ), the extruder 170 of Embodiment 13 is different in that, like the extruder 150 of Embodiment 11 (see Figure 19 ), arc-shaped connecting portions 171 with a specified radius are integrally provided at the corner portions inside the pair of cylinders 21, 22.

[0167] In the extruder 170 of Embodiment 13 formed in the above manner, it is also possible to exhibit substantially the same effects as the extruders 150, 160 of the above-described Embodiments 11 and 12.

[0168] <Embodiment 14>

[0169] As Figure 22 shown, compared with the extruder 90 of Embodiment 5 (see Figure 13 ), the extruder 180 of Embodiment 14 is different in that a rotation oscillation suppressing member 181 for suppressing the rotational oscillation of a pair of screws 50 is provided inside the pair of cylinders 21, 22 (the pair of large transfer passages TP2).

[0170] Specifically, the rotation oscillation suppressing member 181 is provided inside the large block BL5 and is formed in a substantially glasses shape when viewed from the axial direction of the pair of screws 50. The outer peripheral portion of the rotation oscillation suppressing member 181 is fitted to the inner walls of the pair of cylinders 21, 22. In addition, the rotation oscillation suppressing member 181 has a certain wall thickness, and the pair of screws 50 are rotatably arranged in the inner peripheral portion of the rotation oscillation suppressing member 181 with a clearance of "substantially zero".

[0171] In the extruder 180 of Embodiment 14 formed in the above manner, the same effects as those of the extruder 90 of Embodiment 5 described above can also be achieved. In addition, in the extruder 180 of Embodiment 14, since a rotational oscillation suppressing member 181 for suppressing the rotational oscillation of a pair of screws 50 located within the kneading region AR2 (see Figure 2 ) is provided, it is possible to suppress the flexure of the pair of screws 50 inside the pair of large transfer passages TP2. Thereby, it is possible to prevent the pair of screws 50 from interfering with each other or colliding with the pair of large transfer passages TP2.

[0172] It should be noted that it is not limited to providing one rotational oscillation suppressing member 181 in the large block BL5, and it is also possible to additionally provide a rotational oscillation suppressing member 181 in other large blocks. In this case, it is possible to suppress the occurrence of rotational oscillation within substantially the entire range of the pair of screws 50 and obtain stable rotation of the pair of screws 50.

[0173] <Embodiment 15>

[0174] As Figure 23 shown, the extruder 190 of Embodiment 15 is different from the extruder 180 of Embodiment 14 (see Figure 22 ) in that a block-shaped rotational oscillation suppressing member 191 is sandwiched and provided between the large block BL5 and the large block BL6.

[0175] Specifically, when viewed from the axial direction of the pair of screws 50, the rotational oscillation suppressing member 191 is formed in a cross-sectional shape substantially the same as that of the pair of cylinders 21, 22. In addition, the pair of screws 50 are rotatably arranged in a state where the gap is "substantially zero" in the inner peripheral portion of the rotational oscillation suppressing member 191.

[0176] In the extruder 190 of Embodiment 15 formed in the above manner, the same effects as those of the extruder 180 of Embodiment 14 described above can also be achieved. In addition, in the extruder 190 of Embodiment 15, compared with Embodiment 14, when assembling the cylinder unit CU (see Figure 2 ), it is only necessary to sandwich the rotational oscillation suppressing member 191 between the adjacent large blocks BL5 and BL6, and the assembly workability can be improved.

[0177] It should be noted that it is not limited to providing one rotational oscillation suppressing member 191 between the large blocks BL5 and BL6, and it is also possible to additionally provide a rotational oscillation suppressing member 191 between other large blocks.

[0178] <Embodiment 16>

[0179] As Figure 24As shown, the extruder 200 of Embodiment 16 and the extruder 10 of Embodiment 1 (see Figure 1 and Figure 2 ) have substantially the same basic structure but different uses. The extruder 200 is an extruder for a thermal decomposition system and has the function of thermally decomposing a resin raw material (polymer) PM inside a cylinder unit CU and separating it into a decomposition gas GS (solid arrows in the figure) and a residue RS (dashed arrows in the figure).

[0180] Specifically, a plurality of exhaust ports 201 (four in this embodiment) are provided in the outer peripheral portion of the cylinder unit CU, and these exhaust ports 201 recover the decomposition gas GS. And, the decomposition gas GS enters the residue container 204 from the exhaust port 201 via a gas pipe 203 by the operation of a vacuum pump 202. Then, the decomposition gas GS inside the residue container 204 is cooled to become a liquid monomer (not shown) and stored in a monomer container 205.

[0181] It should be noted that a residue container 204 is connected to the upstream side (left side in the figure) of the monomer container 205, and a vacuum pump 202 is connected to the downstream side (right side in the figure) of the monomer container 205. In addition, a drain cock 206 is provided on the lower side of the monomer container 205, and the liquid monomer stored in the monomer container 205 can be taken out from the drain cock 206.

[0182] On the other hand, the residue RS (solid arrows in the figure) that is melted and kneaded inside the cylinder unit CU enters the residue container 204 via a residue discharge port (discharge port) 207 provided in a small block BL9 (a pair of cylinders 21, 22). That is to say, the residue discharge port 207 for discharging the residue RS after thermal decomposition is connected to the kneading region AR2 via a metering region AR3 and a discharge region AR4. It should be noted that the residue discharge port 207 has the function of discharging the residue RS generated after the thermal decomposition of the resin raw material (polymer) PM to the outside of the pair of cylinders 21, 22. In addition, the residue RS is a softened solid and is stored on the lower side of the residue container 204.

[0183] In the extruder 200 of Embodiment 16 formed in the above manner, it is also possible to achieve substantially the same effects as the extruder 10 of Embodiment 1 described above. That is, it is possible to extend the residence time of the resin raw material (polymer) PM inside the cylinder unit CU to sufficiently perform thermal decomposition, and thus improve the processing capacity.

[0184] <Embodiment 17>

[0185] As Figure 25 shown, the extruder 210 of Embodiment 17 and the extruder 90 of Embodiment 5 (see Figure 13)In comparison, the only difference is that when observing the kneading region AR2 (see Figure 2 ) axially from a pair of screws 50, the distance L1 between the centers c2 of the large transfer passages TP2 is made greater than the distance L between the rotational centers c3 of the pair of screws 50 (L1 > L). As a result, the upper convex portions 211 and the lower convex portions 212 respectively enter between the adjacent pair of screws 50.

[0186] In the extruder 210 of Embodiment 17 formed in the above manner, it is also possible to exhibit substantially the same effects as the extruder 90 of the above-described Embodiment 5. In addition, in the extruder 210 of Embodiment 17, since the upper convex portions 211 and the lower convex portions 212 respectively enter between the adjacent pair of screws 50, it is possible to suppress the pair of screws 50 from approaching each other and interfering.

[0187] <Embodiment 18>

[0188] As Figure 26 shown, the extruder 220 of Embodiment 18 is different from the extruder 210 of Embodiment 17 (see Figure 25 ) in that when observing the kneading region AR2 (see Figure 2 ) axially from a pair of screws 50, the cross-sectional shapes inside the pair of cylinders 21 and 22 are set to semi-circular shapes and are butt-jointed to make the centers c2 of the respective large transfer passages TP2 the same point. In addition, the diameter dimension d4 of the pair of large transfer passages TP2 is made larger than that of the extruder 210 of Embodiment 17 (d4 > d2) so as to be able to accommodate the pair of screws 50 (outer diameter dimension d3) inside.

[0189] In the extruder 220 of Embodiment 18 formed in the above manner, it is also possible to exhibit substantially the same effects as the extruder 210 of the above-described Embodiment 17. In addition, in the extruder 220 of Embodiment 18, since the semi-circular shapes are butt-jointed to make the pair of large transfer passages TP2 have a circular cross-section, the shapes of the pair of cylinders 21 and 22 can be simplified, and thus the extruder 220 can be easily manufactured.

[0190] <Embodiment 19>

[0191] As Figure 27 shown, the extruder 230 of Embodiment 19 is different from the extruder 220 of Embodiment 18 (see Figure 26 ) in that when observing the kneading region AR2 (see Figure 2)When it is (the case), increase the diameter dimension d5 (d5 > d4, d5 ≒ 4.5 × d3) of a pair of large conveying passages TP2. Additionally, the difference is that the rotation center c3 of a pair of screws 50 is offset by a distance t4 (t4 > d3) from the center c2 of the pair of large conveying passages TP2 toward the lower walls 21a, 22a of the pair of cylinders 21, 22.

[0192] In the extruder 230 of the 19th embodiment formed in the above-described manner, it is also possible to exhibit substantially the same effects as those of the extruder 220 of the 18th embodiment described above. In addition to this, in the extruder 230 of the 19th embodiment, it is possible to suppress the resin raw materials (resin pellets PR, molten resin MR) from staying in the lower side in the gravity direction of the large conveying passage TP2 for a long time.

[0193] The present invention is not limited to the above-described respective embodiments, and of course, various changes can be made without departing from the gist thereof. For example, in the above-described respective embodiments, a "twin-screw extruder" equipped with a pair of screws 50 is shown, but the present invention is not limited thereto, and it can also be applied to a single-screw type extruder (single-screw extruder).

[0194] In addition, the materials, shapes, dimensions, quantities, installation positions, etc. of the respective components in the above-described respective embodiments are arbitrary, and it is sufficient that the present invention can be implemented, and it is not limited to the above-described respective embodiments.

[0195] Explanation of reference numerals

[0196] 10: Extruder, 20: Kneading treatment section, 21: Cylinder block, 21a: Lower wall, 21b: Upper wall, 21c: Side wall section, 22: Cylinder block, 22a: Lower wall, 22b: Upper wall, 22c: Side wall section, 23: Hopper, 24: Granule inlet, 25: Granule discharge port, 26: Supply port, 27: Molten resin discharge port (discharge port), 28: Conversion adapter, 29: Conversion adapter, 40: Driving section, 41: Electric motor, 41a: Rotating shaft, 42: Reducer, 42a: Output shaft, 50: Screw, 51: Shaft, 52: Forward feed screw blade (transport section), 52a: Thread tooth, 52b: Fixing hole, 53: Forward feed kneading section (kneading section), 53a: Angular section, 53b: Fixing hole, 60: Extruder, 70: Extruder, 71: Reverse feed screw blade, 71a: Thread tooth, 71b: Fixing hole, 72: Reverse feed kneading section, 72a: Angular section, 72b: Fixing hole, 80: Extruder, 81: Convex portion, 82: Arc portion, 90: Extruder, 100: Extruder, 101: Lower straight section (straight section), 102: Upper straight section (straight section), 110: Extruder, 120: Extruder, 130: Extruder, 140: Extruder, 150: Extruder, 151: Arc-shaped connecting portion, 160: Extruder, 170: Extruder, 171: Arc-shaped connecting portion, 180: Extruder, 181: Rotation and swing suppression component, 190: Extruder, 191: Rotation and swing suppression component, 200: Extruder, 201: Exhaust port, 202: Vacuum pump, 203: Gas pipe, 204: Residue container, 205: Monomer container, 206: Drain cock for removal, 207: Residue discharge port (discharge port), 210: Extruder, 211: Upper convex portion, 212: Lower convex portion, 220: Extruder, 230: Extruder, AR1: Supply area (first area), AR2: Kneading area (second area), AR3: Metering area (third area), AR4: Discharge area, BL1, BL2, BL7 - BL9: Small blocks, BL3 - BL6: Large blocks, BL10, BL11: Large blocks, BS: Base, CL: Minute gap, CL1: Lower gap, CL2: Upper gap, CL3: Gap, CL4: Upper gap, CU: Cylinder block unit, FD: Gravimetric feeder, FL1: Installation floor, FL2: Upper floor, GS: Decomposition gas, HT: Heater, MR: Molten resin (resin raw material), P: Transport pipe, PM: Resin raw material (polymer), PR: Resin granule (resin raw material), RS: Residue, RSA: Area, S1: Cross-sectional area, S2: Cross-sectional area, TP1: Small transport passage, TP2: Large transport passage, W1: Arc-shaped inner wall, W2: Arc-shaped inner wall, c1: Center, c2: Center, c3: Rotation center.

Claims

1. An extruder, characterized in that, Comprising: A cylinder block, which includes a first region and a second region; A screw, which is disposed within the cylinder block; and A hopper, which is provided in the first region of the cylinder block for feeding a resin raw material, In terms of the cross-sectional area of the cylinder block that is orthogonal to the direction from the first region toward the second region, the cross-sectional area of the second region is larger than the cross-sectional area of the first region.

2. The extruder according to claim 1, wherein The screw located within the first region includes a conveying portion, The screw located within the second region includes a conveying portion and a kneading portion.

3. The extruder according to claim 2, wherein The kneading portion includes a reverse-feed kneading portion.

4. The extruder according to claim 1, wherein A discharge port is connected to the second region of the cylinder block, and this discharge port is used for discharging the resin after kneading the resin raw material.

5. The extruder according to claim 1, wherein A discharge port is connected to the second region of the cylinder block, and this discharge port is used for discharging the residue after thermally decomposing the resin raw material.

6. The extruder according to claim 1, wherein The cylinder block further has a third region, The second region is adjacent to the third region, In terms of the cross-sectional area of the cylinder block, the cross-sectional area of the second region is larger than the cross-sectional area of the first region and the cross-sectional area of the third region.

7. The extruder according to claim 1, wherein The cylinder block is provided with a rotation and swing suppression member, and this rotation and swing suppression member suppresses the rotation and swing of the screw located within the second region.

8. The extruder according to claim 1, wherein Two of the cylinder blocks are arranged in parallel, and the interiors of the two cylinder blocks communicate with each other, and the screw is disposed within each cylinder block.

9. The extruder according to claim 8, wherein When observing the second region from the axial direction of the screw, the rotation center of each screw is offset from the rotation center of each cylinder block toward the lower wall forming each cylinder block.

10. The extruder according to claim 9, wherein The lower wall has a convex portion that enters between adjacent screws, The convex portion has an arc portion along the outer shape of the screw.

11. The extruder according to claim 8, wherein When observing the second region from the axial direction of the screw, the rotation center of the screw coincides with the center of the cylinder block.

12. The extruder according to claim 9 or 11, wherein A straight portion is provided between adjacent cylinder blocks, and this straight portion tangentially connects the arc-shaped inner walls forming one cylinder block and the arc-shaped inner walls forming the other cylinder block.

13. The extruder according to claim 8, wherein The cylinder block is provided with a side wall portion, and this side wall portion can support the opposite side of the adjacent screw that is opposite to the facing side.

14. The extruder according to claim 13, wherein The lower wall forming the cylinder block has a convex portion that enters between adjacent screws, The convex portion has an arc portion along the outer shape of the screw.

15. The extruder according to claim 13, wherein a straight portion is provided on at least one of the lower wall forming the cylinder and the upper wall on the opposite side of the side where the lower wall is provided, and the straight portion tangentially connects the arc-shaped inner walls forming one cylinder and the arc-shaped inner walls forming the other cylinder to each other.

16. The extruder according to claim 8, wherein when observing the second region in the axial direction of the screw, the shape inside each cylinder is rectangular.

17. The extruder according to claim 16, wherein arc-shaped connecting portions are respectively provided at the corner portions inside each cylinder.

18. The extruder according to claim 16 or 17, wherein the lower wall forming each cylinder has a convex portion that enters between adjacent screws, the convex portion has an arc portion along the outer shape of the screw.

Images