JPS5946775B2 - Extruder control method - Google Patents

Extruder control method

Info

Publication number
JPS5946775B2
JPS5946775B2 JP52078249A JP7824977A JPS5946775B2 JP S5946775 B2 JPS5946775 B2 JP S5946775B2 JP 52078249 A JP52078249 A JP 52078249A JP 7824977 A JP7824977 A JP 7824977A JP S5946775 B2 JPS5946775 B2 JP S5946775B2
Authority
JP
Japan
Prior art keywords
setting signal
speed setting
extruder
thickness
thermoplastic polymer
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
Application number
JP52078249A
Other languages
Japanese (ja)
Other versions
JPS5411967A (en
Inventor
靖典 堀
真州雄 兜森
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujifilm Holdings Corp
Original Assignee
Fuji Photo Film Co Ltd
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 Fuji Photo Film Co Ltd filed Critical Fuji Photo Film Co Ltd
Priority to JP52078249A priority Critical patent/JPS5946775B2/en
Publication of JPS5411967A publication Critical patent/JPS5411967A/en
Publication of JPS5946775B2 publication Critical patent/JPS5946775B2/en
Expired 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
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/911—Cooling
    • B29C48/9135—Cooling of flat articles, e.g. using specially adapted supporting means
    • B29C48/914—Cooling of flat articles, e.g. using specially adapted supporting means cooling drums
    • 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
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/07—Flat, e.g. panels
    • B29C48/08—Flat, e.g. panels flexible, e.g. films
    • 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
    • B29C48/92—Measuring, controlling or regulating
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92009—Measured parameter
    • B29C2948/92114—Dimensions
    • B29C2948/92152—Thickness
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92323—Location or phase of measurement
    • B29C2948/92428—Calibration, after-treatment, or cooling zone
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/9258—Velocity
    • B29C2948/9259—Angular velocity
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92609—Dimensions
    • B29C2948/92647—Thickness
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92819—Location or phase of control
    • B29C2948/92857—Extrusion unit
    • B29C2948/92876—Feeding, melting, plasticising or pumping zones, e.g. the melt itself
    • B29C2948/92885—Screw or gear
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92819—Location or phase of control
    • B29C2948/92857—Extrusion unit
    • B29C2948/92904—Die; Nozzle zone
    • 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
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion

Landscapes

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

Description

【発明の詳細な説明】 本発明は押出機の制御方法、さらに詳しくは押出機のス
クリューの回転速度を制御して均一な厚みを有する熱可
塑性重合体シートを製造する方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling an extruder, and more particularly to a method for manufacturing a thermoplastic polymer sheet having a uniform thickness by controlling the rotational speed of a screw in an extruder.

一般に熱可塑性重合体シートは、熱可塑性重合体を溶融
状態で押し出し、強制冷却されているキヤステングドラ
ム表面に流延して冷却固化した後キヤステングドラムか
ら剥ぎ取ることによつて製造される。Generally, thermoplastic polymer sheets are manufactured by extruding a thermoplastic polymer in a molten state, casting it onto the surface of a casting drum that is being forcedly cooled, solidifying it by cooling, and then peeling it off from the casting drum.

この連続した熱可塑性重合体シートの製造に際して厚み
斑のないものを得ることは困難である。When manufacturing this continuous thermoplastic polymer sheet, it is difficult to obtain one without uneven thickness.

従来この厚み斑を是正する方法としては、流延された熱
可塑性重合体シートの厚みを厚み計によつて検出し、こ
の厚みの実測値と目標値との偏差から圧力設定信号を算
出し、この圧力設定信号と、押出機の吐出圧力を検出し
て得た吐出圧力信号とを圧力調節計に入力してその偏差
から基準回転速度設定信号を算出し、この信号を速度制
御装置に入力して押出機のスクリューの回転速度を制御
する方法が知られている（特開昭４９−２３８５８号）
。スクリューの回転速度を一定に保つように制御すれば
、吐出圧力が大きく変動して比較的小さい範囲で厚み斑
が生じる（小周期変動）。Conventionally, the method of correcting this thickness unevenness is to detect the thickness of the cast thermoplastic polymer sheet using a thickness gauge, calculate the pressure setting signal from the deviation between the actual thickness value and the target value, and This pressure setting signal and the discharge pressure signal obtained by detecting the discharge pressure of the extruder are input to the pressure controller, a reference rotation speed setting signal is calculated from the deviation, and this signal is input to the speed control device. There is a known method for controlling the rotational speed of an extruder screw (Japanese Patent Laid-Open No. 49-23858).
. If the rotation speed of the screw is controlled to be kept constant, the discharge pressure will fluctuate greatly, causing thickness unevenness in a relatively small range (small period fluctuation).

また吐出圧力を一定に保つと、スクリューの回転速度が
大きく変動するが、比較的小さい範囲では厚み斑が生じ
ない。その反面大きな周期の変動が生じる（大周期変動
）。上記の制御方法は、吐出圧力と厚みの両方を検出し
、これらからカスケード制御を行なうものであるため、
小周期変動と大周期変動が除去され、ほぼ均一な厚みを
有する熱可塑性重合体シートを得ることができる。Furthermore, when the discharge pressure is kept constant, the rotational speed of the screw fluctuates greatly, but thickness unevenness does not occur within a relatively small range. On the other hand, large period fluctuations occur (large period fluctuations). The above control method detects both discharge pressure and thickness and performs cascade control from these.
Small period fluctuations and large period fluctuations are eliminated, and a thermoplastic polymer sheet having a substantially uniform thickness can be obtained.

しかしこの方法はカスケード制御であるため、安定確実
な制御を行なうことができないとともに、応答性が遅い
という難点がある。However, since this method uses cascade control, it is difficult to perform stable and reliable control, and the response is slow.

本発明は上記欠点を解決するもので、応答性が早く、し
かも安定確実な制御を行なうことができる押出機の制御
方法を提供することを目的とするものである。The present invention solves the above-mentioned drawbacks, and aims to provide a method for controlling an extruder that has quick response and can perform stable and reliable control.

本発明の制御方法は、厚み計で測定した厚みから吐出量
を算出し、この吐出量と目標値の偏差から基準回転速度
設定信号を算出し、一方圧力検出器で測定した吐出圧力
を圧力調節計に入力して補正回転速度設定信号を算出し
、この補正回転速度設定信号と前記基準回転速度設定信
号とを加算した信号でスクリユ一の回転数を制御するよ
うにしたことを特徴とするものである。The control method of the present invention calculates the discharge amount from the thickness measured with a thickness gauge, calculates a reference rotation speed setting signal from the deviation between this discharge amount and a target value, and adjusts the discharge pressure measured by a pressure detector. A correction rotation speed setting signal is calculated by inputting the correction rotation speed setting signal into a meter, and the rotation speed of the screw is controlled by a signal obtained by adding this correction rotation speed setting signal and the reference rotation speed setting signal. It is.

本発明においては、基準回転速度設定信号に補正回転速
度設定信号とを加え、得られた回転速度設定信号でスク
リユ一の回転速度を制御するものであり、カスケード制
御を行なつていないから、応答性が早く、しかも安定確
実な制御を行なうことができる。In the present invention, the correction rotation speed setting signal is added to the reference rotation speed setting signal, and the rotation speed of the screw is controlled by the obtained rotation speed setting signal, and since cascade control is not performed, the response is It is possible to perform fast, stable and reliable control.

以下図面を参照して本発明の制御方法について説明する
。The control method of the present invention will be explained below with reference to the drawings.

モータ１０によつて押出機１１のスクリユ一（図示せず
）が回転される。このスクリユ一の回転によつて熱可塑
性重合体が溶融状態で吐出され、フイルタ一１２に送ら
れる。このフイルタ一１２を経た熱可塑性重合体は、成
型ダイ１３からキヤステングドラム１４上に流延される
。このキヤステングドラム１４は強制冷却されているた
め、流延された熱可塑性重合体が固化してシートとなる
。このキヤステングドラム１４で送られた熱可塑性重合
体シートは、剥離ローラ１５で剥離され、後の工程で巻
き取られる。前記剥離ローラ１５の後方に厚み計１６が
配されており、厚みを横方向にサンプリングしてその積
分値が測定される。A screw (not shown) of an extruder 11 is rotated by the motor 10. As the screw rotates, the thermoplastic polymer is discharged in a molten state and sent to the filter 12. The thermoplastic polymer that has passed through the filter 12 is cast from a molding die 13 onto a casting drum 14. Since this casting drum 14 is forcedly cooled, the cast thermoplastic polymer solidifies into a sheet. The thermoplastic polymer sheet sent by the casting drum 14 is peeled off by a peeling roller 15 and wound up in a subsequent process. A thickness gage 16 is disposed behind the peeling roller 15, and the thickness is sampled in the lateral direction and its integral value is measured.

前記キヤステングドラム１４は速度計１７でその回転速
度が測定される。これらの厚み計からの厚み信号（積分
値）と、速度計１７からの回転速度信号とが演算装置１
８の乗算回路に送られ乗算されて吐出量信号が算出され
る。なお、吐出量の代わりに、厚み信号だけを演算装置
１８に入力して後述する演算を行なうことができる。演
算装置１８では、厚み信号と回転速度信号とによつて得
られた吐出量信号が、吐出量の目標値と比較され、その
偏差から基準回転速度設定信号が算出される。The rotation speed of the casting drum 14 is measured by a speed meter 17. The thickness signals (integral values) from these thickness gauges and the rotational speed signal from the speedometer 17 are sent to the calculation device 1.
The signal is sent to a multiplication circuit No. 8 and multiplied to calculate a discharge amount signal. Note that instead of the discharge amount, only the thickness signal can be input to the calculation device 18 to perform the calculation described later. In the calculation device 18, the discharge amount signal obtained from the thickness signal and the rotation speed signal is compared with the target value of the discharge amount, and a reference rotation speed setting signal is calculated from the deviation.

一方、押出機１０の吐出圧力は、圧力検出器１９で測定
され、その信号が圧力調節計２０に送られる。On the other hand, the discharge pressure of the extruder 10 is measured by a pressure detector 19, and its signal is sent to a pressure regulator 20.

この圧力調節計２０で補正回転速度設定信号が算出され
る。この補正回転速度設定信号と、演算装置１８からの
基準回転速度設定信号とが速度制御装置２１に送られ、
ここで加算される。This pressure regulator 20 calculates a corrected rotational speed setting signal. This corrected rotational speed setting signal and the reference rotational speed setting signal from the calculation device 18 are sent to the speed control device 21,
It is added here.

これらの信号は、基準回転速度設定信号が全体の９割程
度の大きさであり、残りの１割程度が補正回転速度設定
信号である。この加算された回転速度信号によつてモー
タ１１の回転速度が制御される。Of these signals, the standard rotational speed setting signal accounts for about 90% of the total, and the remaining 10% is the correction rotational speed setting signal. The rotation speed of the motor 11 is controlled by this added rotation speed signal.

またモータ１１の回転速度は速度計２１で検出され、速
度制御装置２１に送られて、モータ１１の回転速度を自
動制する。したがつて本発明では、所定の厚みを得るに
必要な吐出量信号から算出された基準回転速度設定信号
に、吐出圧力の変動量を回転速度信号に変換した補正回
転速度設定信号とを加算して押出機の回転速度を制御す
るようになつている。Further, the rotational speed of the motor 11 is detected by a speedometer 21 and sent to a speed control device 21, which automatically controls the rotational speed of the motor 11. Therefore, in the present invention, a corrected rotation speed setting signal obtained by converting the amount of variation in discharge pressure into a rotation speed signal is added to a reference rotation speed setting signal calculated from a discharge amount signal necessary to obtain a predetermined thickness. The rotation speed of the extruder is controlled by

このため、補正回転速度設定信号によつて吐出圧力の変
動が減少され、また基準回転速度設定信号によつて吐出
量の変動が減少される。したがつて、前者によつて小周
期変動が、また後者によつて大周期変動が除去され、厚
み斑のない熱可塑性重合体シートが得られる。上記構成
を有する本発明によれば、カスケード制御を行なつてい
ないから、応答性が早くなり、変動が生じた場合でも早
く減衰させることができるとともに、安定確実な制御を
行なうことができる。Therefore, fluctuations in the discharge pressure are reduced by the corrected rotational speed setting signal, and fluctuations in the discharge amount are reduced by the reference rotational speed setting signal. Therefore, the former eliminates small-period fluctuations, and the latter eliminates large-period fluctuations, and a thermoplastic polymer sheet without uneven thickness can be obtained. According to the present invention having the above configuration, since cascade control is not performed, the response is quick, and even if fluctuations occur, they can be attenuated quickly, and stable and reliable control can be performed.

【図面の簡単な説明】[Brief explanation of the drawing]

図面は本発明の制御方法を示す概略図である。 １０・・・・・・押出機、１１・・・・・・モータ、１
４・・・・・・キヤステングドラム、１６・・・・・・
厚み計、１７・・・・・・速度計、１９・・・・・・圧
力検出器、２２・・・・・・速度計。The drawings are schematic diagrams showing the control method of the present invention. 10... Extruder, 11... Motor, 1
4... Casting drum, 16...
Thickness gauge, 17... Speed meter, 19... Pressure detector, 22... Speed meter.

Claims (1)

【特許請求の範囲】 １ 押出機から吐出された熱可塑性重合体をキヤステン
グドラム上に流延して熱可塑性重合体シートを製造する
方法において、キヤステングドラムで流延された熱可塑
性重合体シートの厚みを検出し、この厚みと設定値との
偏差から基準回転速度設定信号を算出し、この基準回転
速度設定信号に、前記押出機の吐出圧力から得た補正回
転速度設定信号を加算し、この加算された信号で押出機
のスクリューの回転速度を制御して均一な厚みを有する
熱可塑性重合体シートを製造するようにしたことを特徴
とする押出機の制御方法。 ２ 前記基準回転速度設定信号が全体の９割で、残りが
補正回転速度設定信号であることを特徴とする特許請求
の範囲第１項記載の押出機の制御方法。[Scope of Claims] 1. A method for producing a thermoplastic polymer sheet by casting a thermoplastic polymer discharged from an extruder onto a casting drum, in which the thermoplastic polymer is cast on a casting drum. The thickness of the sheet is detected, a reference rotational speed setting signal is calculated from the deviation between this thickness and the set value, and a corrected rotational speed setting signal obtained from the discharge pressure of the extruder is added to this reference rotational speed setting signal. A method for controlling an extruder, characterized in that the rotational speed of a screw in an extruder is controlled using the added signal to produce a thermoplastic polymer sheet having a uniform thickness. 2. The extruder control method according to claim 1, wherein the reference rotation speed setting signal accounts for 90% of the total, and the remainder is a correction rotation speed setting signal.
JP52078249A 1977-06-30 1977-06-30 Extruder control method Expired JPS5946775B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP52078249A JPS5946775B2 (en) 1977-06-30 1977-06-30 Extruder control method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP52078249A JPS5946775B2 (en) 1977-06-30 1977-06-30 Extruder control method

Publications (2)

Publication Number Publication Date
JPS5411967A JPS5411967A (en) 1979-01-29
JPS5946775B2 true JPS5946775B2 (en) 1984-11-14

Family

ID=13656719

Family Applications (1)

Application Number Title Priority Date Filing Date
JP52078249A Expired JPS5946775B2 (en) 1977-06-30 1977-06-30 Extruder control method

Country Status (1)

Country Link
JP (1) JPS5946775B2 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63201399U (en) * 1987-06-17 1988-12-26
JP2536321B2 (en) * 1991-04-18 1996-09-18 豊田合成株式会社 Extrusion control device of extruder
JP2659515B2 (en) * 1994-01-31 1997-09-30 帝人株式会社 Extruder discharge pressure control device
JP2014193604A (en) * 2013-02-28 2014-10-09 Toray Ind Inc Manufacturing method of a sheet and manufacturing apparatus of a sheet

Also Published As

Publication number Publication date
JPS5411967A (en) 1979-01-29

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