Extruder

Abstract

The size of the extruder (10) in the conveying direction is reduced. An extruder (10) includes: an upstream screw (52) positioned within a cylinder (36) and including a forward screw thread (54); and a downstream screw (62) located within the cylinder connected to the cylinder (36). D1 / d1lt, where d1 is the valley diameter and D1 is the peak diameter of the upstream screw (52), and d2 is the valley diameter and D2 is the peak diameter of the downstream screw (62); and D2 / d2 is satisfied.

Description

Technical Field

[0001] The present invention relates to an extruder. Background Art

[0002] A twin-screw extruder is disclosed in Patent Document 1. A pair of screws provided in a cylinder are composed of a conveying section, a kneading section, and a discharging section from the upstream side.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2009-184303 Summary of the Invention

[0006] When the extruder includes two cylinders, in the cylinder located on the upstream side in the resin material conveying direction, in order to convey the resin material to the cylinder on the downstream side, it is necessary to increase the pressure. As a method of increasing the pressure, the length of the cylinder on the upstream side in the conveying direction can be set to be long, and in this case, the size of the extruder in the conveying direction will become large.

[0007] Other problems and new features will become clear from the description of this specification and the drawings.

[0008] An extruder according to an embodiment includes: an upstream screw portion located in the cylinder on the upstream side and including a conveying portion; and a downstream screw portion located in the cylinder on the downstream side connected to the cylinder on the upstream side. In a case where the root diameter of the upstream screw portion is set to d1 and the crest diameter is set to D1, and the root diameter of the downstream screw portion is set to d2 and the crest diameter is set to D2, D1 / d1 < D2 / d2 holds.

[0009] Advantages of the Invention

[0010] According to an embodiment of the present application, compared with a configuration in which D1 / d1 ≥ D2 / d2 holds, the size of the extruder in the conveying direction can be reduced. Brief Description of the Drawings

[0011] Figure 1 A partial cross-sectional view showing the structure of the extruder according to Embodiment 1.

[0012] Figure 2A For Figure 1 is a cross-sectional view taken along line A-A.

[0013] Figure 2B For Figure 1 is a cross-sectional view taken along line B-B.

[0014] Figure 3 is a cross-sectional view schematically showing the crest diameter of the crest portion and the root diameter of the root portion of the screw.

[0015] Figure 4A A perspective view showing the forward feed thread of the upstream area.

[0016] Figure 4B A side view showing the forward feed thread in the upstream area.

[0017] Figure 5A It is a perspective view showing the forward kneading in the upstream area.

[0018] Figure 5B It is a side view showing the forward kneading in the upstream area.

[0019] Figure 6 To show Figure 1 A cross-sectional view of a portion of the cross section along line AA.

[0020] Figure 7 To show Figure 1 A cross-sectional view of a portion of the cross section along line BB.

[0021] Figure 8 To show Figure 1 A cross-sectional view of a portion of the cross section along line CC.

[0022] Fig. 9 To show Figure 1 A cross-sectional view of a portion of the cross section along line DD.

[0023] Fig.10 This is a partial cross-sectional view showing the structure of the extruder according to the second embodiment.

[0024] Fig.11 It is a partial cross-sectional view showing the structure of the extruder of Embodiment 3.

[0025] Fig. 12A It is a cross-sectional view showing a portion of the extruder according to the fourth embodiment where the reverse feed screw is provided.

[0026] Fig. 12B It is a cross-sectional view showing a portion of the extruder according to the fourth embodiment where reverse kneading is provided.

[0027] Fig.13A It is a perspective view showing the reverse feed thread of the fourth embodiment.

[0028] Fig. 13B It is a side view of the reverse feed thread of embodiment 4 as viewed from the side.

[0029] Fig.14A This is a perspective view showing the reverse kneading of the fourth embodiment.

[0030] Fig. 14B This is a side view of the reverse kneading according to the fourth embodiment as seen from the side.

[0031] Fig.15A It is a cross-sectional view showing the forward feed thread of the fifth embodiment.

[0032] Fig. 15B It is a cross-sectional view showing the forward feed thread of the sixth embodiment.

[0033] Fig. 15C It is a cross-sectional view showing the forward feed thread of embodiment 7.

[0034] Fig.16 It is a partial cross-sectional view showing the structure of an extruder provided with a temperature changing portion according to a modified example. DETAILED DESCRIPTION

[0035] The following is a detailed description of various embodiments of the present invention using the accompanying drawings. In all the drawings used to illustrate various embodiments, components and devices having the same or substantially the same functions are marked with the same reference numerals, and repeated descriptions are omitted.

[0036] In the following description, the conveying direction of the resin material P described later may be referred to as the Y direction. The Y direction is included in the horizontal direction. The arrow Y in the figure means the Y direction. The base end side of the arrow Y corresponds to the upstream side. The front end side of the arrow Y corresponds to the downstream side.

[0037] In addition, the vertical direction perpendicular to the conveying direction may be referred to as the Z direction. The arrow Z in the figure means the Z direction. The base end side of the arrow Z corresponds to the lower side. The tip end side of the arrow Z corresponds to the upper side.

[0038] In addition, there is a case where the left-right direction perpendicular to both the conveying direction and the vertical direction is called the X direction. The X direction is included in the horizontal direction. The arrow X in the figure means the X direction. Looking from the upstream side to the downstream side in the conveying direction, the base end side of the arrow X is equivalent to the left side of the extruder 10. The front end side of the arrow X is equivalent to the right side of the extruder 10. The X direction, the Y direction, and the Z direction are perpendicular to each other.

[0039] [Implementation Method 1]

[0040] like Figure 1 As shown in FIG. 1 , the extruder 10 of the first embodiment is used for melt kneading of resin pellets PR (an example of resin material P). The extruder 10 is supported by a base 12 fixed to a floor FL. As an example, the extruder 10 is provided with two screws 50 ( Figure 2A , Figure 2B Specifically, the extruder 10 includes a driving unit 20 for rotating two screws 50 and a kneading processing unit 30 including the two screws 50.

[0041] [Drive unit]

[0042] The driving unit 20 includes a motor 22 and a reducer 24. Specifically, the rotational force generated by the motor 22 is transmitted to the reducer 24, and the rotational force reduced in speed and converted into high torque is transmitted from the reducer 24 to the two screws 50 ( Figure 2A , Figure 2B ). Accordingly, the two screws 50 rotate in the same direction. However, depending on the purpose of the melt kneading process, the two screws 50 can also rotate in different directions.

[0043] [Mixing Processing Department]

[0044] The kneading treatment section 30 includes a hopper 32, a cylinder unit 34, and two screws 50 ( Figure 2A , Figure 2B ) and a discharge portion 46.

[0045] <Hopper>

[0046] The resin pellets PR stored in the hopper 32 fall due to gravity and are supplied to the supply port 37A described later. In the kneading treatment section 30, the side where the resin pellets PR before melt kneading are supplied is the "upstream side". The side where the melted resin MR after melt kneading is discharged from the discharge section 46 is the "downstream side".

[0047] <Cylinder unit>

[0048] The cylinder unit 34 is supported by the base 12. The cylinder unit 34 is arranged parallel to the installation floor FL. As an example, the cylinder unit 34 includes a cylinder 36 extending in the Y direction and a cylinder 42 connected to the cylinder 36 and extending in the Y direction. In the cylinder unit 34, a cylinder 42 having a radius D3 ( Figure 2A ) is defined as the upstream region K1. In addition, in the cylinder unit 34, the radius D4 ( Figure 2B ) is set as the downstream side area K2.

[0049] As an example, the cylinder 36 is composed of two blocks 37 arranged in the Y direction. Each of the two blocks 37 is formed with a cylindrical upstream conveying passage 39 penetrating in the Y direction. Two upstream conveying passages 39 ( Figure 2A The upstream block 37 has a supply port 37A. The supply port 37A penetrates from the outside to the upstream conveying passage 39.

[0050] As an example, the cylinder 42 is composed of four blocks 43 arranged in the Y direction. The four blocks 43 form a cylindrical downstream conveying passage 44 penetrating in the Y direction. Two downstream conveying passages 44 ( Figure 2B A discharge portion 46 for discharging the molten resin MR is provided on the downstream side of the cylinder 42 in the Y direction.

[0051] like Figure 2A As shown in FIG. 1 , the radius of the cylinder 36 (upstream conveying passage 39 ) is set to D3 (mm).

[0052] like Figure 2B As shown in FIG. 1 , the radius of the cylinder 42 (downstream conveying passage 44 ) is set to D4 (mm).

[0053] exist Figure 2A as well as Figure 2B In other words, in the XZ cross section perpendicular to the Y direction, the cross-sectional area S1 of the upstream conveying passage 39 is smaller than the cross-sectional area S2 of the downstream conveying passage 44. A step 45 ( Figure 1 The two upstream conveying passages 39 partially overlap each other's facing portions in the X direction and communicate with each other at the overlapping portions. The two downstream conveying passages 44 partially overlap each other's facing portions in the X direction and communicate with each other at the overlapping portions.

[0054] <Screw>

[0055] like Figure 1 As shown, two screw rods 50 ( Figure 2A , Figure 2B ) are arranged inside the cylinder 36 and the cylinder 42. As an example, the two screws 50 are twin-line screws. The two screws 50 have the function of conveying the resin material P (resin pellets PR, molten resin MR) present in the upstream conveying passage 39 and the downstream conveying passage 44 from the upstream side to the downstream side in the Y direction while mixing.

[0056] In addition, the positions of the rotation centers of the two screws 50 coincide with the positions of the centers C of the two upstream conveying passages 39 and the two downstream conveying passages 44. Therefore, in the subsequent description, the position of the central axis of the screw 50 is also referred to as the center C. The two screws 50 do not interfere with each other, and each can rotate smoothly. The screw 50 on the +X side (right side) will be basically described below, and the description of the screw 50 on the -X side (left side) will be omitted.

[0057] The screw 50 includes an upstream screw 52 located in the cylinder 36 and a downstream screw 62 located in the cylinder 42. The upstream screw 52 and the downstream screw 62 have the same central axis and rotate integrally. Figure 1The range A1 indicated by the arrow in the figure means the setting range of the upstream screw 52 in the Y direction. In addition, the range A2 indicated by the arrow means the setting range of the downstream screw 62 in the Y direction. In the present embodiment, as an example, it is preferred that the downstream end of the upstream screw 52 is located (intrudes) in the cylinder 42, and the boundary position between the upstream screw 52 and the downstream screw 62 is located at the boundary position between the upstream area K1 and the downstream area K2.

[0058] <<Definition of Peak Diameter and Valley Diameter>>

[0059] use Figure 3 The screw SQ schematically shown in FIG. 1 is a screw 50 ( Figure 1 ) are explained below. Figure 3 The XZ cross section of the screw SQ is shown. The axial direction of the screw SQ is along the Y direction. The position of the central axis of the screw SQ is represented by the center C. The "peak" of the screw SQ is called the peak M. The "peak diameter" of the screw SQ is set to the peak diameter D (mm). The "valley" of the screw SQ is called the valley V. The "valley diameter" of the screw SQ is set to the valley diameter d (mm). The imaginary line DE is an imaginary circle with the effective diameter of the screw SR as the diameter.

[0060] When viewed in a cross section (XZ cross section) perpendicular to the axial direction of the screw SQ, the "peak M" is located radially outside the screw SQ relative to the imaginary line DE. The "valley V" is located radially inside the screw SQ relative to the imaginary line DE.

[0061] When observed on the XZ cross section, the "peak diameter D" is the distance D between the center C and the position PA, which is the position on the outer peripheral surface when the distance from the center C to the outer peripheral surface of the peak portion M is the maximum.

[0062] When viewed on the XZ cross section, the “valley diameter d” is the distance between the center C and a position PB on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley V is the smallest.

[0063] <<Upstream Screw>>

[0064] like Figure 1 As shown, as an example, the upstream screw 52 includes a shaft 52A, a forward feed flight 54 as an example of a conveying portion, a forward feed kneading portion 56 as an example of a kneading portion, and a forward feed flight 58 as an example of a conveying portion.

[0065] <<<Positive thread>>>

[0066] The forward feed screw 54 and the forward feed screw 58 convey the resin material P to the downstream side in the Y direction as they rotate. The length of the forward feed screw 54 in the Y direction is longer than the length of the forward feed screw 58 in the Y direction. In addition, the forward feed screw 54 and the forward feed screw 58 have the same structure except for the length in the Y direction. Therefore, the forward feed screw 54 will be described later, and the description of the forward feed screw 58 will be omitted.

[0067] like Figure 4A As shown in FIG. 1 , the rotation direction of the upstream screw 52 is set to the clockwise direction indicated by the arrow CW. Figure 4B As shown, the forward thread 54 is formed into a right-hand thread having a spiral peak 54A and a valley 54B so that the resin material P ( Figure 1 ) moves along the Y direction (positive direction). Figure 4A As shown, an insertion shaft 52A ( Figure 1 ) The shaft 52A is serratedly engaged with the fixing hole 54C in order to enable large torque transmission.

[0068] <<<Positive Feeding and Kneading>>>

[0069] like Figure 1 As shown, the forward kneading machine 56 kneads the resin material P as it rotates. In addition, the forward kneading machine 56 also has a function of conveying the resin material P to the downstream side while kneading it.

[0070] like Figure 5A as well as Figure 5B As shown, the forward kneading 56 is formed into a shape in which a plurality of peaks 56A and valleys 56B are arranged in a spiral shape so that the resin material P ( Figure 1 ) is kneaded and transported along the Y direction. In addition, an insertion shaft 52A ( Figure 1 ) of the fixing hole 56C ( Figure 5A ) The shaft 52A is serratedly engaged with the fixing hole 56C in order to enable large torque transmission.

[0071] <<Downstream Screw>>

[0072] like Figure 1 As shown, the downstream screw 62 includes a shaft 52A, forward kneading parts 64, 65, 66 as an example of a kneading part, and forward flight 72, 73, 74 as an example of another conveying part. The forward kneading parts 64, 65, 66 and the forward flight 72, 73, 74 are alternately arranged along the Y direction.

[0073] <<<Positive Feeding and Kneading>>>

[0074] The forward kneading part 64 is located on the downstream side in the Y direction relative to the forward kneading screw 58. The forward kneading parts 64, 65, and 66 knead the resin material P as they rotate. In addition, the forward kneading parts 64, 65, and 66 also have the function of conveying the resin material P to the downstream side while kneading. The forward kneading parts 64, 65, and 66 are components having an outer shape similar to that of the forward kneading part 56, but are different in size from those of the forward kneading part 56. The forward kneading parts 64, 65, and 66 are fixed to the shaft 52A in the same manner as the forward kneading part 56.

[0075] <<<Positive thread>>>

[0076] The forward feed screws 72, 73, 74 convey the resin material P to the downstream side in the Y direction as they rotate. The forward feed screws 72, 73, 74 have different lengths in the Y direction. The forward feed screws 72, 73, 74 are components having an outer shape similar to that of the forward feed screw 54, but are different in size from that of the forward feed screw 54. The forward feed screws 72, 73, 74 are fixed to the shaft 52A in the same manner as the forward feed screw 54.

[0077] [Valley diameter and peak diameter of the normal thread]

[0078] like Figure 6 As shown, in the upstream screw 52, ​​the forward thread 54 has a peak 54A and a valley 54B. The peak 54A refers to a portion located radially outside the imaginary circle with the effective diameter of the upstream screw 52 as the diameter. The valley 54B refers to a portion located radially inside the imaginary circle with the effective diameter of the upstream screw 52 as the diameter. Figure 6 In FIG. 1 , for comparison, the forward feed thread 54 is shown by a solid line, and the forward feed thread 72 described later is shown by a two-dot chain line.

[0079] When viewed in the XZ cross section, the peak diameter D1 (mm) of the forward thread 54 is the distance between the center C and a position P1 on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the peak 54A is the maximum.

[0080] When viewed in the XZ cross section, the valley diameter d1 (mm) of the forward thread 54 is the distance between the center C and a position P2 on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley portion 54B is the smallest.

[0081] Moreover, the radius of the cylinder 36 is set to D3 (mm). Here, the ratio of the peak diameter D1 to the valley diameter d1 is set to R1 (= D1 / d1). In addition, the ratio of the radius D3 of the cylinder 36 to the valley diameter d1 is set to R3 (= D3 / d1). The illustration of the ratio R1 and the ratio R3 is omitted.

[0082] like Figure 7As shown, in the downstream screw 62, the forward feed thread 72 has a peak portion 72A and a valley portion 72B. The peak portion 72A refers to the portion located radially outside compared to the imaginary circle with the effective diameter of the downstream screw 62 as the diameter. The valley portion 72B refers to the portion located radially inside compared to the imaginary circle with the effective diameter of the downstream screw 62 as the diameter.

[0083] When observed in the X-Z cross-section, the peak diameter D2 (mm) of the forward feed thread 72 is the distance between the center C and the position P3, and the position P3 is the position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the peak portion 72A is the maximum.

[0084] When observed in the X-Z cross-section, the valley diameter d2 (mm) of the forward feed thread 54 is the distance between the center C and the position P4, and the position P4 is the position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley portion 72B is the minimum.

[0085] Moreover, let the radius of the cylinder block 42 be D4 (mm). Here, let the ratio of the peak diameter D2 to the valley diameter d2 be R2 (= D2 / d2). In addition, let the ratio of the radius D4 of the cylinder block 42 to the valley diameter d2 be R4 (= D4 / d2). The illustration of the ratio R2 and the ratio R4 is omitted.

[0086] As Figure 6 shown, when comparing the forward feed thread 54 and the forward feed thread 72, the relationship D1 / d1 < D2 / d2 holds, and the relationship D3 / d1 < D4 / d2 holds. In other words, the ratio R1 is less than the ratio R2, and the ratio R3 is less than the ratio R4.

[0087] [Valley diameter and peak diameter of forward feed kneading]

[0088] As Figure 8 shown, in the upstream screw 52, the forward feed kneading 56 has a peak portion 56A and a valley portion 56B. The peak portion 56A refers to the portion located radially outside compared to the imaginary circle with the effective diameter of the upstream screw 52 as the diameter. The valley portion 56B refers to the portion located radially inside compared to the imaginary circle with the effective diameter of the upstream screw 52 as the diameter.

[0089] When observed in the X-Z cross-section, the peak diameter D5 (mm) of the forward feed kneading 56 is the distance between the center C and the position P5, and the position P5 is the position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the peak portion 56A is the maximum.

[0090] When observed in the X-Z cross-section, the valley diameter d5 (mm) of the forward feed kneading 56 is the distance between the center C and the position P6, and the position P6 is the position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley portion 56B is the minimum.

[0091] Here, the ratio of the peak diameter D5 to the valley diameter d5 is defined as R5 (= D5 / d5). Additionally, the ratio of the radius D3 to the valley diameter d5 is defined as R6 (= D3 / d5). Illustrations of the ratios R5 and R6 are omitted. In this embodiment, as an example, R5 = R1 and R6 = R3.

[0092] As Fig. 9 shown, in the downstream screw 62, the forward conveying kneading 64 has a peak portion 64A and a valley portion 64B. The peak portion 64A refers to the portion located radially outside a hypothetical circle having the effective diameter of the downstream screw 62 as its diameter. The valley portion 64B refers to the portion located radially inside a hypothetical circle having the effective diameter of the downstream screw 62 as its diameter.

[0093] When observed in the X-Z cross-section, the peak diameter D6 (mm) of the forward conveying kneading 64 is the distance between the center C and the position P7, where the position P7 is the position on the outer peripheral surface of the peak portion 64A when the distance from the center C to the outer peripheral surface of the peak portion 64A is the maximum.

[0094] When observed in the X-Z cross-section, the valley diameter d6 (mm) of the forward conveying kneading 64 is the distance between the center C and the position P8, where the position P8 is the position on the outer peripheral surface of the valley portion 64B when the distance from the center C to the outer peripheral surface of the valley portion 64B is the minimum.

[0095] Here, the ratio of the peak diameter D6 to the valley diameter d6 is defined as R7 (= D6 / d6). Additionally, the ratio of the radius D4 to the valley diameter d6 is defined as R8 (= D4 / d6). Illustrations of the ratios R7 and R8 are omitted. In this embodiment, as an example, R7 = R2 and R8 = R4. That is, in the forward conveying kneading 56 ( Figure 8 ), forward conveying kneading 64, the relationship where the ratio R5 is less than the ratio R7 and the ratio R6 is less than the ratio R8 holds. In this way, the same relationship as that of the forward conveying threads 54, 72 ( Figure 1 ) also holds for the forward conveying kneadings 56, 64.

[0096] As described above, in the extruder 10, when the valley diameter of the upstream screw 52 is set as d1 and the peak diameter is set as D1, and the valley diameter of the downstream screw 62 is set as d2 and the peak diameter is set as D2, D1 / d1 < D2 / d2 holds. Moreover, when the radius of the cylinder 36 is set as D3 and the radius of the cylinder 42 is set as D4, D3 / d1 < D4 / d2 holds. Further, in the extruder 10, each value is set such that D1 / d1 is less than 1.5. In other words, each value is set such that D2 / d2 is greater than or equal to 1.5.

[0097] [Function of Embodiment 1]

[0098] Refer to Figures 1 to 9, the operation of the extruder 10 of Embodiment 1 will be described. In the extruder 10, the ratio R1 (= D1 / d1) of the upstream screw 52 in the upstream region K1 is smaller than the ratio R2 (= D2 / d2) of the downstream screw 62 in the downstream region K2. Therefore, the space volume in the upstream region K1 becomes smaller than the space volume in the downstream region K2, and the pressure boosting ability in the upstream region K1 becomes higher. Therefore, even if the length of the upstream region K1 in the Y direction is set to a short length, the required pressure can be obtained in the upstream region K1. Therefore, compared with the configuration where D1 / d1 ≥ D2 / d2 holds, the size of the extruder 10 in the conveying direction (Y direction) can be reduced.

[0099] The space volume in the upstream region K1 becomes smaller and the pressure boosting ability becomes higher. As a result, the filling rate of the resin material P in the upstream region K1 becomes higher, and the conveying ability of the resin material P also becomes higher. Therefore, the phenomenon that the resin pressure and the volatile gas generated during kneading in the downstream region K2 flow back to the upstream region K1 is suppressed, and thus the continuous operation of the extruder 10 can be stably performed.

[0100] Here, the length of the upstream region K1 in the Y direction is set to L1 (mm) ( Figure 1 ). If the length L1 is too short, there is a possibility that the pressure boosting ability is insufficient. The required pressure boosting ability in the upstream region K1 depends on the internal pressure of the downstream region K2, and RA (= L1 / (2×D3)) needs to be 1.5 or more. This RA is the ratio of the length L1 to the inner diameter (= 2×radius D3) of the cylinder 36. The ratio RA is preferably 7.0 or more.

[0101] In the extruder 10, in addition to the relationship D1 / d1 < D2 / d2 holding, the relationship D3 / d1 < D4 / d2 also holds. Therefore, considering not only the radius of the screw 50 but also the radius of the cylinder unit 34, the space volume is set within a preferable range. Accordingly, the phenomenon that the resin pressure and the volatile gas generated during kneading in the downstream region K2 flow back to the upstream region K1 can be further suppressed.

[0102] In the extruder 10, the downstream screw 62 includes forward conveying kneaders 64, 65, 66. Accordingly, compared with the configuration where the downstream screw 62 only has forward conveying threads 72, 73, 74, the resin material P can be heated by the heat generated by the shearing action accompanying the rotation of the screw 50.

[0103] In the extruder 10, the downstream screw 62 includes forward conveying threads 72, 73, 74. Accordingly, compared with the configuration where the downstream screw 62 only has forward conveying kneaders 64, 65, 66, the conveying ability of the resin material P can be improved.

[0104] In the extruder 10 , the upstream screw 52 includes the forward feed flight 56 ​​. This allows the resin material P to be heated by heat generated by the shearing action accompanying the rotation of the screw 50 , compared to a configuration in which the upstream screw 52 only has the forward feed flight 54 .

[0105] [Implementation Method 2]

[0106] An extruder 80 according to a second embodiment of the present disclosure will be described with reference to the drawings. In addition, the same reference numerals are given to the same or equivalent components as those of the extruder 10 according to the first embodiment, and description thereof will be omitted.

[0107] Fig.10 FIG. 8 shows a portion of the extruder 80 in the Y direction. The extruder 80 and the extruder 10 ( Figure 1 ) is different in that an adapter 82 is added to the cylinder 36. The configuration other than the adapter 82 is the same except for the length of the screw 50 in the Y direction.

[0108] The adapter 82 is provided at the end portion of the cylinder 36 on the downstream side in the conveying direction (Y direction) of the resin material P. The adapter 82 is an example of an expanded diameter portion. The adapter 82 has a hole portion 83 that constitutes a part of the conveying passage of the resin material P. The shape of the cross section XZ of the hole portion 83 is circular. The radius of the upstream end of the hole portion 83 in the Y direction is D3. The radius of the downstream end of the hole portion 83 in the Y direction is D4. Moreover, the radius of the hole portion 83 increases continuously from D3 to D4 as it approaches the cylinder 42. In other words, the inner diameter of the hole portion 83 increases continuously as it approaches the cylinder 42.

[0109] In the extruder 80, the radius of the adapter 82 increases continuously from D3 to D4. In other words, no step is formed. Accordingly, since a part of the resin material P transported in the Y direction is suppressed from being retained in the step portion, the resin material P can be smoothly transported from the cylinder 36 to the cylinder 42.

[0110] [Implementation method 3]

[0111] An extruder 90 according to a third embodiment of the present disclosure will be described with reference to the drawings. In addition, the same reference numerals are given to the same or equivalent components as those of the extruder 10 according to the first embodiment, and description thereof will be omitted.

[0112] Fig.11 The extruder 90 is shown in FIG. The extruder 90 is similar to the extruder 10 ( Figure 1 ) is that the downstream screw 62 is provided with positive feed threads 92 and 94, and the first block 43 (cylinder 42) is provided with a flow passage 93 to replace the discharge portion 46 ( Figure 1 ) and a pressure regulating portion 96 is provided.

[0113] The flow channel 93 penetrates the block 43 in the Z direction and communicates with the downstream conveying passage 44. Water W is supplied as an example of a liquid material to the flow channel 93. In place of the water W, liquid resin or the like may be used as another example of the liquid material.

[0114] The pressure regulating portion 96 is provided on the downstream side of the cylinder 42. As an example, the pressure regulating portion 96 has a radius smaller than the radius D3 ( Figure 6 ) The hole 97 extends along the Y direction. The pressure regulating portion 96 can adjust the internal pressure of the cylinder 42 by changing the radius (inner diameter) of the hole 97.

[0115] In the extruder 90, the resin material P is supplied to the upstream region K1, and the water W is supplied to the downstream region K2. Here, in the upstream region K1, the aforementioned relationship between the peak diameter and the valley diameter holds true, and the pressure-increasing capacity is improved. Accordingly, for the resin material P, the water W, and the gas generated by mixing in the downstream region K2, the backflow from the downstream region K2 to the upstream region K1 can be suppressed because the sealing property in the upstream region K1 is improved. In addition, since there is no need to increase the number of blocks 37 in order to suppress the backflow, the size of the extruder 90 in the conveying direction (Y direction) can be reduced.

[0116] [Implementation Method 4]

[0117] As Embodiment 4 of the present disclosure, Fig. 12A as well as Fig. 12B 2 shows a configuration in which a reverse feed screw 102 and a reverse feed kneading unit 106 are added to the extruder 10 . Fig.13A as well as Fig. 13B The reverse feed thread 102 is shown in FIG. Fig.14A as well as Fig. 14B In addition, regarding the structure which is the same or equivalent to the structure of the extruder 10 of Embodiment 1, refer to the attached Figure 1 , while omitting the figure number, the same figure number is marked and the description is omitted.

[0118] like Fig.13A as well as Fig. 13B As shown, the direction of rotation is arrow CW ( Fig.13A ) is formed into a threaded shape having a helical peak portion 102A and a valley portion 102B so as to move the resin material P in the direction of the arrow -Y (the reverse direction). The reverse thread 102 is an example of a reverse conveying portion. In addition, a fixing hole 102C ( Fig.13A ) The shaft 52A is serratedly engaged with the fixing hole 102C in order to enable large torque transmission.

[0119] like Fig. 12A As shown in the figure, as an example, the reverse feed screw 102 is provided at the upstream end of the upstream screw 52 in the Y direction. In addition, a discharge port 103 is provided at the upstream end of the upstream region K1 of the extruder 10. Here, the reverse feed screw 102 rotates as the upstream screw 52 rotates, thereby enabling the resin material P retained on the upstream side of the supply port 37A to be discharged from the discharge port 103.

[0120] like Fig.14A As shown in FIG. 14B, the direction of rotation is arrow CW ( Fig.14A ) is formed in a spiral shape so that the resin material P is mixed and transported in the direction of arrow -Y (reverse direction). The reverse kneading unit 106 is an example of a kneading unit and an example of a reverse transport unit. In addition, the reverse kneading unit 106 has a plurality of valleys 106B. In addition, a fixing hole 106C ( Fig.14A ) The shaft 52A is also serratedly engaged with the fixing hole 106C in order to enable large torque transmission.

[0121] like Fig. 12B As shown in FIG. 1 , as an example, the reverse kneading 106 is provided at the downstream end of the downstream screw 62 in the Y direction. In addition, a discharge port 107 is provided at a portion of the downstream region K2 of the extruder 10. Here, the reverse kneading 106 rotates as the downstream screw 62 rotates, so that the liquid retained in the downstream region K2 is discharged from the discharge portion 46 ( Figure 1 ) The resin material P on the upstream side is discharged from the discharge port 107. In this way, the extruder 10 provided with the reverse feed screw 102 and the reverse feed kneading 106 may also be used.

[0122] [Implementation method 5]

[0123] As Embodiment 5 of the present disclosure, Fig.15A The forward feed screw 112 is shown in FIG. In addition, the same reference numerals are given to the same or equivalent components as those of the extruder 10 of the first embodiment, and the description thereof will be omitted.

[0124] The forward feed thread 112 is an example of a conveying portion. The forward feed thread 112 constitutes a single-line screw 111, and has a peak 112A and a valley 112B. In the forward feed thread 112, the valley 112B having a valley diameter d7 and the peak 112A having a peak diameter D7 are arranged along the radial direction of the screw 111. An insertion shaft 52A ( Figure 1 ) fixing hole 112C.

[0125] The peak portion 112A is a portion located radially outside of an imaginary circle having the effective diameter of the screw 111 as its diameter. The valley portion 112B is a portion located radially inside of an imaginary circle having the effective diameter of the screw 111 as its diameter.

[0126] When observed in the XZ section, the peak diameter D7 (mm) of the forward thread 112 is the distance between the center C and the position P9, which is the position on the outer peripheral surface when the distance from the center C to the outer peripheral surface of the peak portion 112A is the maximum.

[0127] When viewed in the XZ cross section, the valley diameter d7 (mm) of the forward thread 112 is the distance between the center C and a position P10, which is a position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley portion 112B is the smallest.

[0128] In addition, the ratio R9 (= D7 / d7) of the peak diameter D7 to the valley diameter d7 in the forward thread 112 is smaller than that of the downstream screw 62 ( Figure 7 ) ratio R2. According to this, the size of the extruder 10 can be reduced even if a single-line forward feed screw 112 is used. The illustration of the ratio R9 is omitted.

[0129] [Implementation Method 6]

[0130] As Embodiment 6 of the present disclosure, Fig. 15B The forward feed screw 114 is shown in FIG. In addition, the same reference numerals are given to the same or equivalent components as those of the extruder 10 of the first embodiment, and the description thereof will be omitted.

[0131] The forward feed screw 114 is an example of a conveying portion. The forward feed screw 114 constitutes a single-line screw 113, and has a peak portion 114A and a valley portion 114B. An insertion shaft 52A ( Figure 1 ) fixing hole 114C.

[0132] The peak 114A refers to a portion located radially outward compared to an imaginary circle whose diameter is the effective diameter of the screw 113. The valley 114B refers to a portion located radially inward compared to an imaginary circle whose diameter is the effective diameter of the screw 113. When viewed from the axial direction (Y direction) of the screw 113, the valley 114B is set to be annular. The peak 114A is a protrusion-shaped portion protruding radially outward from a part of the circumference of the valley 114B.

[0133] When observed in the XZ cross section, the peak diameter D8 (mm) of the forward thread 114 is the distance between the center C and the position P11, which is the position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the peak portion 114A is the maximum.

[0134] When viewed in the XZ section, the valley diameter d8 (mm) of the forward thread 114 is the distance between the center C and a position P12 on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley portion 114B is the smallest.

[0135] The ratio R10 (= D8 / d8) of the peak diameter D8 to the valley diameter d8 in the forward thread 114 is smaller than that of the downstream screw 62 ( Figure 7 ) ratio R2. According to this, the size of the extruder 10 can be reduced even if a single-line forward feed screw 114 is used. The illustration of R10 is omitted.

[0136] [Implementation method 7]

[0137] As Embodiment 7 of the present disclosure, Fig. 15C The forward feed screw 116 is shown in FIG. In addition, the same reference numerals are given to the same or equivalent components as those of the extruder 10 of the first embodiment, and the description thereof will be omitted.

[0138] The forward feed thread 116 is an example of a conveying section. The forward feed thread 116 constitutes a three-line screw 115, which has three peaks 116A and three valleys 116B. The three peaks 116A and the three valleys 116B are arranged in the circumferential direction of the screw 115. In other words, a plurality of peaks 116A and valleys 116B are provided in the circumferential direction of the screw 115. An insertion shaft 52A ( Figure 1 ) fixing hole 116C.

[0139] The peak 116A is a portion located radially outside of an imaginary circle having the effective diameter of the screw 115 as its diameter. The valley 116B is a portion located radially inside of an imaginary circle having the effective diameter of the screw 115 as its diameter.

[0140] When observed in the XZ cross section, the peak diameter D9 (mm) of the forward thread 116 is the distance between the center C and the position P13, which is the position on the outer peripheral surface when the distance from the center C to the outer peripheral surface of the peak portion 116A is the maximum.

[0141] When viewed in the XZ section, the valley diameter d9 (mm) of the forward thread 116 is the distance between the center C and a position P14, which is a position on the outer peripheral surface where the distance from the center C to the outer peripheral surface of the valley portion 116B is the smallest.

[0142] The ratio R11 (= D9 / d9) of the peak diameter D9 to the valley diameter d9 in the forward thread 116 is smaller than that of the downstream screw 62 ( Figure 7 ) ratio R2. According to this, even if a three-line type positive feed screw 116 is used, the extruder 10 ( Figure 1 ) dimensions. The illustration of the ratio R11 is omitted.

[0143] [Deformation column]

[0144] The present disclosure 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" having two (a pair of) screws 50 is shown, but the present disclosure is not limited thereto, and it is also applicable to a single-screw type extruder (single-screw extruder).

[0145] In the extruder 10, the configuration may be such that only the relationship D1 / d1 < D2 / d2 holds and the relationship D3 / d1 < D4 / d2 does not hold.

[0146] As Fig.16 shown, in the extruder 10 or the like, temperature changing units 122 may be provided in the block 37 (cylinder block 36) and the block 43 (cylinder block 42), respectively. The temperature changing unit 122 includes at least one of a cooling unit that cools the resin material P and a heating unit that heats the resin material P. The number of the cooling units and the number of the heating units may each be either odd or even. As an example of the cooling unit, a pipe through which a liquid such as water flows may be provided, and cooling may be performed by heat exchange through the pipe. As an example of the heating unit, a heater may be provided, and heating may be performed by energization and heat generation.

[0147] In addition, the temperature changing unit 122 may be provided only in the cylinder block 36. The temperature changing unit 122 may be provided only in the cylinder block 42.

[0148] In the extruder 10, only the forward feed screw 54 may be provided in the upstream region K1. Only the forward feed screw 72 may be provided in the downstream region K2. Only the forward feed kneader 64 may be provided in the downstream region K2. Only the forward feed screw 54 may be provided in the upstream region K1, and only the forward feed screw 72 may be provided in the downstream region K2. Only the forward feed screw 54 may be provided in the upstream region K1, and only the forward feed kneader 64 may be provided in the downstream region K2.

[0149] Only the forward feed screw 54 may be provided in the upstream region K1, and only the forward feed kneader 64 and the forward feed screw 72 may be provided in the downstream region K2. Only the forward feed screw 54 and the forward feed kneader 56 may be provided in the upstream region K1.

[0150] An adapter 82 may be added to the extruder 90.

[0151] In addition, the materials, shapes, dimensions, numbers, installation positions, etc. of the respective constituent elements in the above-described respective embodiments are arbitrary, and as long as the present disclosure can be achieved, it is not limited to the above-described respective embodiments and modification examples.

[0152] Description of Reference Numerals

[0153] 10: Extruder, 12: Base, 20: Drive unit, 22: Motor, 24: Speed ​​reducer, 26: Gear mechanism, 30: Kneading unit, 32: Hopper, 34: Cylinder unit, 36: Cylinder, 37: Block, 37A: Supply port, 39: Upstream conveying passage, 42: Cylinder, 43: Block, 44: Downstream conveying passage, 45: Step, 46: Discharge unit, 50: Screw, 52: Upstream screw, 52A: Shaft, 54: Normal feed screw (an example of a conveying unit), 54A: Peak, 54B: Valley, 54C: Fixing hole, 56: Normal feed kneading (an example of a kneading unit), 56A: Peak, 56B: Valley, 56C: Fixing hole, 58: Normal feed screw (an example of a conveying unit), 62: Downstream Screw, 64: forward kneading (an example of a kneading section), 64A: peak, 64B: valley, 65: forward kneading (an example of a kneading section), 66: forward kneading (an example of a kneading section), 72: forward screw (an example of another conveying section), 72A: peak, 72B: valley, 73: forward screw (an example of another conveying section), 74: forward screw (an example of another conveying section), 80: extruder, 82: adapter (an example of an expansion section), 83: hole, 90: extruder, 92: forward screw, 93: flow channel, 94: forward screw, 96: pressure regulating section, 102: reverse screw (an example of a reverse conveying section), 102A: peak, 102B: valley, 102C: fixing hole, 103: discharge port , 106: reverse kneading (an example of a kneading section and an example of another reverse conveying section), 106A: peak, 106B: valley, 106C: fixed hole, 107: discharge port, 111: screw, 112: forward thread (an example of a conveying section), 112A: peak, 112B: valley, 112C: fixed hole, 113: screw, 114: forward thread (an example of a conveying section), 114A: peak, 114B: valley, 114C: fixed hole, 115: screw, 116: forward thread (a row of conveying sections), 116A: peak, 116B: valley, 116C: fixed hole, 122: temperature changing section, A1: range, A2: range, C: center, CW: rotation direction, d: valley diameter, d 1: Valley diameter, d2: Valley diameter, d5: Valley diameter, d6: Valley diameter, D: Peak diameter, D1: Peak diameter, D2: Peak diameter, D3: Radius, D4: Radius, D5: Peak diameter, D6: Peak diameter, DE: Imaginary line, FL: Setting floor, K1: Upstream area, K2: Downstream area, L1: Length, M: Peak, MR: Molten resin, P: Resin material, P1: Position, P2: Position, P3: Position, P4: Position, P5: Position, P6: Position, P7: Position, P8: Position, P9: Position, P10: Position, P11: Position, P12: Position, P13: Position, P14: Position, PA: Position, PB: Position, PR: Resin particles, R1: Ratio, R2: Ratio, R3: Ratio,R4: ratio, R5: ratio, R6: ratio, R7: ratio, R8: ratio, R9: ratio, R10: ratio, R11: ratio, S1: cross-sectional area, S2: cross-sectional area, SQ: screw, V: valley, W: water, Y: conveying direction, Z: vertical direction,

Claims

1. An extruder, characterized in that: Comprising: A first cylinder block having a supply port for supplying resin material; A first screw located within the first cylinder block and including a conveying portion for conveying the resin material; A second cylinder block connected to the first cylinder block; And A second screw located within the second cylinder block, When the root diameter of the first screw is set as d1 and the crest diameter is set as D1, When the root diameter of the second screw is set as d2 and the crest diameter is set as D2, The relationship D1 / d1 < D2 / d2 holds.

2. The extruder according to claim 1, characterized in that When the radius of the first cylinder block is set as D3, When the radius of the second cylinder block is set as D4, The relationship D3 / d1 < D4 / d2 holds.

3. The extruder according to claim 1, characterized in that The second screw includes a kneading portion for kneading the resin material.

4. The extruder according to claim 3, characterized in that The second screw includes another conveying portion for conveying the resin material.

5. The extruder according to claim 1, characterized in that The second screw includes another conveying portion for conveying the resin material.

6. The extruder according to claim 1, characterized in that The first screw includes a kneading portion for kneading the resin material.

7. The extruder according to claim 1, characterized in that At the end of the first cylinder block on the downstream side in the conveying direction of the resin material, there is a diameter-expanding portion whose inner diameter continuously increases as it approaches the second cylinder block.

8. The extruder according to claim 1, characterized in that The second cylinder block is provided with a flow channel for supplying liquid material, On the downstream side of the second cylinder block in the conveying direction of the resin material, there is a pressure regulating portion capable of regulating the internal pressure of the second cylinder block.

9. The extruder according to claim 1, characterized in that At the end of the first screw on the upstream side in the conveying direction of the resin material, there is a reverse conveying portion for conveying the resin material in the direction opposite to the conveying direction.

10. The extruder according to claim 1, characterized in that At the end of the second screw on the downstream side in the conveying direction of the resin material, there is another reverse conveying portion for conveying the resin material in the direction opposite to the conveying direction.

11. The extruder according to claim 10, characterized in that The other reverse conveying portion conveys the resin material while kneading it.

12. The extruder according to claim 1, characterized in that At least one of the first cylinder block and the second cylinder block is provided with a temperature changing portion capable of changing the temperature of the resin material.

13. The extruder according to claim 1, characterized in that In the conveying portion, the root portion having the root diameter and the crest portion having the crest diameter are arranged radially on the first screw.

14. The extruder according to claim 13, characterized in that The root portion is set in an annular shape, The crest portion protrudes outward in the radial direction from a part of the circumferential direction of the root portion.

15. The extruder according to claim 13, characterized in that A plurality of the valley portions and the peak portions are provided in a circumferential direction of the first screw.

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