JPH0655409B2 - Tapered twin screw extruder - Google Patents

Tapered twin screw extruder

Info

Publication number
JPH0655409B2
JPH0655409B2 JP2222261A JP22226190A JPH0655409B2 JP H0655409 B2 JPH0655409 B2 JP H0655409B2 JP 2222261 A JP2222261 A JP 2222261A JP 22226190 A JP22226190 A JP 22226190A JP H0655409 B2 JPH0655409 B2 JP H0655409B2
Authority
JP
Japan
Prior art keywords
screw
rotor
tapered
valley bottom
front wall
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
JP2222261A
Other languages
Japanese (ja)
Other versions
JPH04103329A (en
Inventor
正夫 森山
Original Assignee
正夫 森山
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 正夫 森山 filed Critical 正夫 森山
Priority to JP2222261A priority Critical patent/JPH0655409B2/en
Priority to CA002049256A priority patent/CA2049256A1/en
Priority to US07/747,644 priority patent/US5232280A/en
Priority to EP19910307743 priority patent/EP0472431A3/en
Publication of JPH04103329A publication Critical patent/JPH04103329A/en
Publication of JPH0655409B2 publication Critical patent/JPH0655409B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
    • B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
    • B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
    • B29B7/46—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft
    • B29B7/48—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft with intermeshing devices, e.g. screws
    • B29B7/484—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft with intermeshing devices, e.g. screws with two shafts provided with screws, e.g. one screw being shorter than the other
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
    • B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
    • B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
    • B29B7/46—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft
    • B29B7/48—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft with intermeshing devices, e.g. screws
    • B29B7/488—Parts, e.g. casings, sealings; Accessories, e.g. flow controlling or throttling devices
    • B29B7/489—Screws
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
    • B29C48/40—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders
    • B29C48/402—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders the screws having intermeshing parts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/505—Screws
    • B29C48/52—Screws with an outer diameter varying along the longitudinal axis, e.g. for obtaining different thread clearance
    • B29C48/525—Conical screws
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/74—Mixing; Kneading using other mixers or combinations of mixers, e.g. of dissimilar mixers ; Plant
    • B29B7/7476—Systems, i.e. flow charts or diagrams; Plants
    • B29B7/7495—Systems, i.e. flow charts or diagrams; Plants for mixing rubber

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)

Description

【発明の詳細な説明】 ＜産業上の利用分野＞ 本発明は、プラスチック、ゴム等の高粘性材料を押し出
すために用いられるテーパ二軸押出機に関する。TECHNICAL FIELD The present invention relates to a taper twin-screw extruder used for extruding highly viscous materials such as plastic and rubber.

＜従来の技術＞ 一般に、テーパ二軸押出機は、ロータの先端に至るほど
容器断面積が減少するため、それに反比例して内圧が増
大し、従ってロータ長さの割に強力な押出力が得られる
という長所がある。<Prior Art> Generally, in a tapered twin-screw extruder, the container cross-sectional area decreases toward the tip of the rotor, so the internal pressure increases in inverse proportion to it, and therefore a strong pushing force is obtained for the rotor length. It has the advantage of being

従来のテーパ二軸押出機のロータに刻設されたスクリュ
ーの山形は、第４図に示すような梯形であって、互に係
合する二軸ロータの山と谷、谷と山が噛み合っており、
スクリューの谷間に充填された材料がロータと共に後退
するのを阻止してスクリューと材料の界面ですべりを生
じさせることにより材料を先端の方へ押し出すことがで
きる。The angle of the screw engraved on the rotor of the conventional taper twin-screw extruder is a trapezoid as shown in Fig. 4, and the ridges and valleys and valleys and ridges of the twin-screw rotors engaging with each other mesh with each other. Cage,
The material can be extruded towards the tip by preventing the material filled in the screw valleys from receding with the rotor and causing slippage at the screw-material interface.

＜発明が解決しようとする課題＞ 第４図に示した従来技術において、粘性が高くスクリュ
ー界面での摩擦抵抗の大きな材料を用いたり、先端押出
口での押圧力を強くするためロータ駆動力を増大させる
と、先端から押し戻す抵抗力も増大し、ロータ駆動力の
増分に対する先端押出口の増分が急激に純化し、飽和す
る。<Problems to be Solved by the Invention> In the prior art shown in FIG. 4, a rotor driving force is used in order to use a material having high viscosity and high frictional resistance at the screw interface, or to increase the pressing force at the tip extrusion port. When it is increased, the resistance force pushing back from the tip also increases, and the increment of the tip extrusion port with respect to the increment of the rotor driving force is rapidly purified and saturated.

そこで本発明は、このような押出力の限界を破り、最高
押圧力が一段と向上したテーパ二軸押出機の提供を解決
課題とする。Then, this invention makes it a solution subject to provide the taper twin-screw extruder which violated the limit of such pushing force, and improved the maximum pushing force further.

＜課題を解決するための手段＞ 本発明のテーパ二軸押出機は、テーパ型ロータの側面に
刻設されたスクリューの山の形状が、テーパ谷底面と、
その谷底面の後端部が丸く立ち上ってテーパ谷底面と略
垂直に交わる前壁面と、その前壁面の頂上から後方へ延
びる頂面と、その頂面の後縁から上記テーパ谷底面に向
って径が漸次減少する後斜面とから成る略台形に形成さ
れ、二軸ロータの係合関係が、二軸心を含む平面上にお
いて一方のロータスクリューの谷底面の前縁に他方のロ
ータスクリューの前壁面が最接近するよう構成されたこ
とを特徴としている。<Means for Solving the Problems> In the taper twin-screw extruder of the present invention, the shape of the screw peaks engraved on the side surface of the taper type rotor has a taper valley bottom surface,
The rear end of the valley bottom rises roundly and intersects the tapered valley bottom in a direction substantially perpendicular to the front wall, the top surface that extends rearward from the top of the front wall, and from the trailing edge of the top surface toward the tapered valley bottom. It is formed in a substantially trapezoidal shape with a rear slope whose diameter gradually decreases, and the engagement relationship of the biaxial rotor is such that the front edge of the root bottom surface of one rotor screw is in front of the other rotor screw on the plane including the biaxial center. The feature is that the walls are configured so that they are closest to each other.

＜作用＞ スクリューの前壁面がテーパ面に対し略平行の先端へ向
く力を材料に与えるのに対し、スクリューの後斜面が斜
め後方へ向く力を材料に与えるため、両方の力が不平衡
となり先端へ向く力がより大きくなるとともに、後斜面
に仂く力の半径方向分力が材料をスクリューの谷から遊
離させて界面における摩擦抵抗を減少させる。<Action> While the front wall of the screw gives the material a force that is directed to the tip approximately parallel to the taper surface, the backward slope of the screw gives the material a force that is directed obliquely rearward, so both forces become unbalanced. As the force towards the tip becomes greater, the radial component of the force behind the back slope frees the material from the screw troughs and reduces the frictional resistance at the interface.

また、頂面から凹んだ谷の断面積に比べて、谷底面から
凸出した山の断面積が小さいので、二軸心を含む平面上
における両スクリューが噛み合った状態において、材料
が残留しうる空間があり、従ってロータ軸を強力に駆動
した際に生ずるロータ軸先端部を外側へ開かせる力が緩
和される。In addition, since the cross-sectional area of the peak protruding from the bottom of the valley is smaller than the cross-sectional area of the valley recessed from the top surface, the material may remain in the state where both screws are engaged on the plane including the biaxial center. There is a space, and therefore, the force for opening the rotor shaft tip end to the outside when the rotor shaft is strongly driven is alleviated.

＜実施例＞ 第１図に本発明が実施されたテーパ二軸押出機の全体を
示し、第２図に第１図のＡ−Ａ断面図を示す。<Example> FIG. 1 shows the entire taper twin-screw extruder in which the present invention is carried out, and FIG. 2 shows a sectional view taken along line AA of FIG.

スクリューが互にかみ合って回転する二軸のテーパ型
（円錐形）ロータ１Ａ，１Ｂは、その根元部が軸受け
（図示せず）により支持され、その先端は自由端をな
し、第２図に矢印で示すように異方向に回転駆動され
る。容器３は、ロータ１Ａ，１Ｂのスクリューの山の回
転軌跡となる二軸円錐面に近接した内側面と、この二軸
円錐面の根元上部に設けられた方形の材料投入口４と、
先端に設けられた材料押出口５を有し、軸受けを支持し
ている。Two-axis taper type (conical) rotors 1A and 1B in which the screws are engaged with each other to rotate are supported at their roots by bearings (not shown), and the tips of the rotors are free ends. It is driven to rotate in different directions as indicated by. The container 3 has an inner side surface adjacent to a biaxial conical surface which is a locus of rotation of the screw ridges of the rotors 1A and 1B, and a square material inlet 4 provided at an upper part of the root of the biaxial conical surface.
It has a material extrusion port 5 provided at the tip and supports a bearing.

この容器３内のロータ１Ａ，１Ｂの側面に刻設されたス
クリューの山の形状は、第３図にその二軸心を含む平面
に沿う断面で示す通り、スクリューの谷の回転軌跡によ
り規定される面と同一面上にあるテーパ谷底面６と、そ
のテーパ谷底面６の後端部７が丸く立ち上ってテーパ谷
底面と略垂直に交わる前壁面８と、その前壁面８の頂上
９から後方へ延びる頂面１０と、その頂面１０の後縁１
１から１ピッチ後方のテーパ谷底面６αに向って径が漸
次線形に減少する後斜面１２とから成る略台形に形成さ
れ、第２図に示す二軸心０１，０２を含む平面Ｐ上にお
ける両ロータの係合関係は、第３図に示すように、一方
のロータ１Ａのスクリューの谷底面の前縁１３に、他方
のロータ１Ｂのスクリューの前壁面８ｂの頂上が最接近
するよう構成されている。The shape of the screw crests engraved on the side surfaces of the rotors 1A and 1B in the container 3 is defined by the locus of rotation of the screw troughs, as shown in the cross section along the plane including the two axial centers in FIG. From the top 9 of the front wall surface 8 and the front wall surface 8 where the rear end portion 7 of the taper valley bottom surface 6 rises in a round shape and intersects the taper valley bottom surface substantially perpendicularly. Top surface 10 extending to and a trailing edge 1 of the top surface 10
On a plane P including a biaxial center 0 1 , 0 2 shown in FIG. 2, which is formed in a substantially trapezoidal shape including a rear slope 12 whose diameter gradually decreases linearly toward the taper valley bottom surface 6α from 1 to 1 pitch backward. As shown in FIG. 3, the engagement relationship between the two rotors is such that the top of the front wall surface 8b of the screw of the other rotor 1B comes closest to the front edge 13 of the root of the screw of the one rotor 1A. Has been done.

実施例における各部の寸法を示すと、スクリューのピッ
チ５０mm、頂面１０の軸方向長さ１０mm、後斜面１２の
軸方向長さ１５mmである。The dimensions of each part in the examples are as follows: the screw pitch is 50 mm, the top surface 10 has an axial length of 10 mm, and the rear slope 12 has an axial length of 15 mm.

＜発明の効果＞ 本発明によれば、スクリューの前壁面が材料を強力に押
し出すとともに後斜面が材料をロータから遊離させてロ
ータと材料との界面の摩擦抵抗を減少させて材料の押出
力を増大させ、しかも、第３図に示すように両ロータが
噛み合った状態においても、なお材料の残留しうる適度
な空間Ｓ１，Ｓ２があるため、内圧が増大するロータ先
端部においても、その内圧が材料に与えられてロータ軸
を外側へ開かせるまでに至らず、ロータ自由端が容器内
壁面と干渉する危険が緩和される。<Effects of the Invention> According to the present invention, the front wall surface of the screw strongly pushes out the material, and the rear slant surface separates the material from the rotor to reduce the frictional resistance at the interface between the rotor and the material, thereby pushing out the material. Further, even when both rotors are engaged with each other as shown in FIG. 3, there are appropriate spaces S 1 and S 2 in which material can remain, so that even at the rotor tip portion where the internal pressure increases, The internal pressure is not applied to the material to open the rotor shaft to the outside, and the risk of the free end of the rotor interfering with the inner wall surface of the container is reduced.

【図面の簡単な説明】[Brief description of drawings]

第１図は本発明実施例の全体を示す部分切欠図、第２図
は第１図のＡ−Ａ横断面図、第３図は本発明実施例の二
軸心０１，０２を含む平面Ｐに沿うロータ断面の部分拡
大図、第４図は従来例のロータ断面の部分拡大図であ
る。 １Ａ，１Ｂ……テーパ型ロータ ２Ａ，２Ｂ……軸受け ３……容器 ４……材料投入口 ５……材料押出口 ６……テーパ谷底面 ８……前壁面 １０……頂面 １２……後斜面FIG. 1 is a partial cutaway view showing the whole embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 3 includes biaxial centers 0 1 , 0 2 of the embodiment of the present invention. FIG. 4 is a partially enlarged view of the rotor cross section along the plane P, and FIG. 4 is a partially enlarged view of the rotor cross section of the conventional example. 1A, 1B ... Tapered rotor 2A, 2B ... Bearing 3 ... Container 4 ... Material input port 5 ... Material extrusion port 6 ... Tapered valley bottom 8 ... Front wall 10 ... Top 12 ... Rear Slope

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】テーパ型ロータの側面に刻設されたスクリ
ューの山の形状が、テーパ谷底面と、その谷底面の後端
部が丸く立ち上ってテーパ谷底面と略垂直に交わる前壁
面と、その前壁面の頂上から後方へ延びる頂面と、その
頂面の後縁から上記テーパ谷底面に向って径が漸次減少
する後斜面とから成る略台形に形成され、二軸ロータの
係合関係が、二軸心を含む平面上において一方のロータ
スクリューの谷底面の前縁に他方のロータスクリューの
前壁面が最接近するよう構成されたことを特徴とするテ
ーパ二軸押出機。1. The shape of a screw crest engraved on the side surface of a tapered rotor has a tapered valley bottom surface and a front wall surface where the rear end of the valley bottom surface rises in a round shape and intersects the tapered valley bottom surface substantially vertically. It is formed in a substantially trapezoidal shape consisting of a top surface that extends rearward from the top of the front wall surface and a rear slope whose diameter gradually decreases from the trailing edge of the top surface toward the taper valley bottom surface. The taper twin-screw extruder is characterized in that the front wall surface of the other rotor screw is closest to the front edge of the root bottom surface of the one rotor screw on a plane including the biaxial center. 【請求項２】スクリューの山の軸方向ピッチに対し上記
頂面の軸方向長さが１５ないし３０％である、第１項記
載のテーパ二軸押出機。2. The tapered twin-screw extruder according to claim 1, wherein the axial length of the top surface is 15 to 30% of the axial pitch of the screw crests.
JP2222261A 1990-08-22 1990-08-22 Tapered twin screw extruder Expired - Lifetime JPH0655409B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2222261A JPH0655409B2 (en) 1990-08-22 1990-08-22 Tapered twin screw extruder
CA002049256A CA2049256A1 (en) 1990-08-22 1991-08-15 Twin conical screw extruder
US07/747,644 US5232280A (en) 1990-08-22 1991-08-20 Twin conical screw extruder provided with pressurizing members
EP19910307743 EP0472431A3 (en) 1990-08-22 1991-08-22 Twin conical screw extruder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2222261A JPH0655409B2 (en) 1990-08-22 1990-08-22 Tapered twin screw extruder

Publications (2)

Publication Number Publication Date
JPH04103329A JPH04103329A (en) 1992-04-06
JPH0655409B2 true JPH0655409B2 (en) 1994-07-27

Family

ID=16779619

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2222261A Expired - Lifetime JPH0655409B2 (en) 1990-08-22 1990-08-22 Tapered twin screw extruder

Country Status (1)

Country Link
JP (1) JPH0655409B2 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4813826B2 (en) * 2005-06-09 2011-11-09 三菱重工業株式会社 Biaxial feeder, sheeting apparatus and kneading system using the same
ATE511976T1 (en) * 2007-07-19 2011-06-15 Erwin Schnabl SCREW HOUSING FOR A TWIN SCREW EXTRUDER, THE TWIN SCREW EXTRUDER AND THE METHOD FOR PRODUCING A SCREW HOUSING
SI2580042T1 (en) * 2010-06-09 2014-12-31 Helmuth Schulz Device for processing material by mixing and/or plasticating
JP6044245B2 (en) * 2012-10-03 2016-12-14 横浜ゴム株式会社 Method for producing film-like member for pneumatic tire

Also Published As

Publication number Publication date
JPH04103329A (en) 1992-04-06

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