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DE4129979A1 - Temp. profile sensor for extruder nozzle or die - is shaped to suit specific task, carried in low conductivity material and can be used for manual or automatic optimisation of temp. control - Google Patents

Temp. profile sensor for extruder nozzle or die - is shaped to suit specific task, carried in low conductivity material and can be used for manual or automatic optimisation of temp. control

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Publication number
DE4129979A1
DE4129979A1 DE19914129979 DE4129979A DE4129979A1 DE 4129979 A1 DE4129979 A1 DE 4129979A1 DE 19914129979 DE19914129979 DE 19914129979 DE 4129979 A DE4129979 A DE 4129979A DE 4129979 A1 DE4129979 A1 DE 4129979A1
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DE
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Patent type
Prior art keywords
temp
sensor
control
used
use
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.)
Withdrawn
Application number
DE19914129979
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German (de)
Inventor
Markus Cremer
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.)
VEREINIGUNG ZUR FOERDERUNG DES INSTITUTS fur KUNSTSTOFFVERARBEITUNG IN INDUSTRIE und HANDWERK AN DER RHEIN -WESTF TECHNISCHEN HOCHSCHULE AACHEN EV 5100 AACHEN DE
VER FOERDERUNG INST KUNSTSTOFF
Original Assignee
VEREINIGUNG ZUR FOERDERUNG DES INSTITUTS FUER KUNSTSTOFFVERARBEITUNG IN INDUSTRIE UND HANDWERK AN DER RHEIN.-WESTF. TECHNISCHEN HOCHSCHULE AACHEN EV, 5100 AACHEN, DE
VER FOERDERUNG INST KUNSTSTOFF
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
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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C47/00Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C47/08Component parts, details or accessories; Auxiliary operations
    • B29C47/92Measuring, controlling or regulating
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/76Measuring, controlling or regulating
    • B29C45/78Measuring, controlling or regulating of temperature
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2947/00Indexing scheme relating to extrusion moulding
    • B29C2947/92Measuring, controlling or regulating
    • B29C2947/92504Controlled parameter
    • B29C2947/92704Temperature
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2947/00Indexing scheme relating to extrusion moulding
    • B29C2947/92Measuring, controlling or regulating
    • B29C2947/92819Location or phase of control
    • B29C2947/92857Extrusion unit
    • B29C2947/92876Feeding, melting, plasticising or pumping zones, e.g. the melt itself
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2947/00Indexing scheme relating to extrusion moulding
    • B29C2947/92Measuring, controlling or regulating
    • B29C2947/92819Location or phase of control
    • B29C2947/92857Extrusion unit
    • B29C2947/92904Die; Nozzle zone
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C47/00Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C47/0009Extrusion 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 articles

Abstract

A sensor is described for measuring axial and radial temp. profiles both in the nozzle in front of an extruder or injection moulding screw and in an extrusion die. Conventional sensors have relatively slow response and temp. profile measurement is suspect due to heat conductivity errors. The new sensor has a number of measuring points and is built into a carrier of a poor conducting material. The outer shape of the sensor is designed to suit the specific area of use. A process for use of the sensor in temp. control is described and gives temp. profile which can be manually or automatically used for optimisation of process and machine control parameters. USE/ADVANTAGE - The sensor and process are used in extruders, injection moulding machines or extruder dies for optimising temp. adjustment, gives increased local accuracy allowing better control of machine or tool temp. and thus improve melt homogeneity.

Description

Die Erfindung betrifft einen Sensor nach Anspruch 1-14 und ein Verfahren zur Optimierung der Maschineneinstellung von Kunststoffverarbeitungsmaschinen nach den Ansprüchen 5 und 6. The invention relates to a sensor according to claim 1-14 and a method for optimizing the machine setting of plastics processing machine according to claims 5 and 6. FIG.

Der im Hauptanspruch näher beschriebene Sensor erlaubt auch wesentlich genauere Temperaturmessungen im Bereich hinter der Schneckenspitze von Plastifizieraggregaten und im Be reich von Extrusionswerkzeugen, insbesondere eine genauere zeitliche Erfassung der Temperatur wegen der geringen An sprechzeiten und eine hohe Ortsauflösung und Anzahl von Meßpunkten wegen der geringen Größe der einzelnen Meßstel len. The sensor described in the main claim in more detail also allows much more accurate temperature measurements in the region behind the screw tip of plasticising and Be rich of extrusion dies, in particular a more precise time detection of the temperature due to the low on response times and a high spatial resolution and number of measuring points, because of the small size of the individual Meßstel len.

Es ist bekannt, daß eine möglichst homogene Temperaturver teilung der Schmelze bei der Kunststoffverarbeitung anzu streben ist. is aim, it is known that a very homogeneous distribution of the melt at Temperaturver plastics processing to. Weiterhin ist bekannt, daß vor der Schnecken spitze radiale und axiale Temperaturprofile auftreten ( 1, 2 ). Furthermore, it is known that in front of the screw tip radial and axial temperature profiles occur (1, 2).

Auch im Extrusionswerkzeug wirken sich Temperaturun terschiede zwischen Werkzeugwand und Schmelze auf die Qualität der Erzeugnisse aus ( 3 ). In the extrusion die to Temperaturun differences act between mold wall and the melt on the quality of products from (3).

Die bislang zur Verfügung stehenden Sensoren erlauben die Messung von radialen Temperaturprofilen. The previously available sensors allow the measurement of radial temperature profiles. Bei der Messung macht man aber, da die üblichen Sensoren massive Stahlteile sind, einen Wärmeableitfehler. When measuring to do but because the usual sensors are massive steel parts, a heat loss.

Die Sensoren, die für Spritzgießmaschinendüsen zur Verfü gung stehen, reduzieren den üblichen freien Strömungsquer schnitt im Düsenbereich stark, sind daher verschleißgefähr det und führen zu erhöhter dissipativer Erwärmung, Druck verlust und benötigter Maschinenleistung. The sensors that are available for injection molding nozzles for Availability checked supply, reduce the usual free flow cross-section in the nozzle area greatly, therefore wear jeopardized and lead to increased dissipative warming, loss pressure and required machine performance. Abhilfe schafft eine Erweiterung des Strömungskanals. Remedy creates an extension of the flow channel. Dadurch wird aber das Massepolster vergrößert, was insbesondere bei kleinen Schußgewichten zu einer größeren Verweilzeit auf Verarbei tungstemperaturniveau führt und damit die Schmelzequalität mindert. This, however, the melt cushion is increased, which in small shot weights particular leads to a larger residence time on process ing temperature level and thus reduce the melt quality.

Zur Beurteilung der Schmelzehomogenität reicht das örtliche und zeitliche Auflösungsvermögen dieser Sensoren nicht aus ( 2 ). To assess the homogeneity of the melt, the spatial and temporal resolution of these sensors is not sufficient (2). Die übliche Vorgehensweise zur Beurteilung der thermi schen und mechanischen Homogenität ist die Anfertigung von Dünnschnitten der erstarrten Schmelze und Betrachtung im Mikroskop ( 2 ), was sehr aufwendig ist. The usual approach for assessing the thermi and mechanical homogeneity is the preparation of thin sections of the solidified melt and viewing under the microscope (2), which is very expensive.

Bei der Einstellung der Werkzeugtemperatur ist aufgrund des fehlenden Wissens über das reale Temperaturprofil im Werk zeug die Einstellung der bestmöglichen Solltemperaturen oft problematisch. When setting the mold temperature due to the lack of knowledge is about the real temperature profile in the work of convincing the setting of optimum target temperatures often problematic. Nicht zuletzt deshalb sind daher die im Hauptanspruch erwähnten Simulationsprogramme von großer Bedeutung. Not least therefore are mentioned in the main claim simulation programs of great importance.

Der Erfindung liegt die Aufgabe zugrunde, das Temperatur profil an den oben angesprochenen Orten mit sehr hoher örtlicher und zeitlicher Auflösung zu vermessen und hieraus Rückschlüsse auf eine bessere Maschineneinstellung und auf die Homogenität der Schmelze zu ziehen. The object underlying the invention is to measure the temperature profile to the above-mentioned places with very high spatial and temporal resolution, and from this draw conclusions on a better machine setting and the homogeneity of the melt.

Diese Aufgabe wird erfindungsgemäß durch die kennzeichnen den Merkmale nach Anspruch 1-7 gelöst. This object is achieved by characterizing the features according to claims 1-7.

Literatur literature

(1) Fritz, HG; (1) Fritz, HG; Grünschloß, E.; Grünschloß, E .; Eyerer, P. Eyerer, P.
Das Schmelztemperaturprofil an der Schneckenspitze - Messung und Interpretation The melting temperature profile at the screw tip - measurement and interpretation
Beitrag zum 11. Stuttgarter Kunststoffkolloquium, 1989 Contribution to the 11th Stuttgart plastic Colloquium, 1989
(2) Bürkle, E. (2) Bürkle, E.
Verbesserte Kenntnis des Plastifiziersystems an Spritzgießmaschinen Improved knowledge of the plasticizing system on injection molding machines
Dissertation an RWTH Aachen, 1989 Dissertation at RWTH Aachen, 1989
(3) Vlachopoulos, J. (3) Vlachopoulos, J.
Effect of die wall cooling or heating on extrudate swell Effect of the wall cooling or heating on extrudates swell
Polym. Polym. Eng. Closely. Sci 29, 1989, 5, S. 685-689 Sci 29, 1989, 5, pp 685-689
(4) Nehren, R. (4) Nehren, R.
Konstruktion einer Meßvorrichtung zur automatischen Erfassung des radialen Temperaturprofiles vor der Schneckenspitze Construction of a measuring device for the automatic detection of the radial temperature profile in front of the screw tip
Studienarbeit am IKV, Aachen, 1991 Student research at the IKV, Aachen, 1991

Claims (7)

1. Sensor wie nach den Ansprüchen 1, 2, 5, 6, 7, 12, 13, des Hauptanspruches, dadurch gekennzeichnet, daß die Geometrie, dh die äußere Form des Sensors für den Einbau in verschiedene Spritzgießmaschinendüsen, den Bereich vor der Schnec kenspitze von Extrusionsanlagen und den Bereich in verschiedenen Extrusionswerkzeugen, z. 1. Sensor as claimed in claims 1, 2, 5, 6, 7, 12, 13, of the main claim, characterized in that the geometry, ie, the outer shape of the sensor for installation in various injection molding nozzle, the area in front of the SNAILS kenspitze of extrusion equipment and the area in various extrusion tools such. B. dem Lippenbe reich eines Breitschlitzextrusionswerkzeuges, jeweils angepaßt wird. B. rich of a wide-slot extrusion die, is in each case adapted to the Lippenbe.
2. Sensor nach Anspruch 1, dadurch gekennzeichnet, daß das schlecht wärmeleitfähi ge Trägermaterial zur Aufnahme der Schub- und Druck kräfte in eine schmale Metallhalterung eingebracht wird. 2. Sensor according to claim 1, characterized in that the bad wärmeleitfähi ge carrier material for receiving the shear and compressive forces is introduced into a narrow metal support. Die Bilder 1-3 zeigen hierzu ein Einbaubeispiel in eine Spritzgießmaschinendüse. this the images 1-3 show an installation example in a Spritzgießmaschinendüse. Die Metallhalterung des Sensors ( Bild 1) muß ebenso wie das Trägermaterial dem jeweiligen Anwendungsfall angepaßt werden. The metal support of the sensor (Figure 1) must be adapted to the respective application as well as the support material. Der Sensor wird an Pos. 1 fixiert. The sensor is fixed to Pos. 1,. Diese Halterung des Sensors muß in einem Düseneinsatz eingesetzt werden (Beispiel Bild 2). This bracket of the sensor must be used in a nozzle insert (example Figure 2). Nach der Montage von Halterung und Einsatz kann der Sensor dann in der in diesem Beispiel angesprochenen Spritzgießmaschinen düse ( Bild 3, Pos. 1) eingebaut werden ( Bild 3). After the assembly of holder and insert the sensor in the addressed in this example injection molding nozzle then (Figure 3, Pos. 1) to be installed (Figure 3). Das Meßkabel wird wieder über einen Kabelkanal weggeführt ( Bild 3, Pos. 2). The measuring cable is using one cable channel carried away (Figure 3, Pos. 2).
3. Sensor nach Anspruch 1, dadurch gekennzeichnet, daß zur Reduzierung der auf zunehmenden Schubspannungen der gesamte Sensor in Strö mungsrichtung sehr kurz ist (1-10 mm). 3. Sensor according to claim 1, characterized in that to reduce the flow direction to increasing shear stresses in the entire sensor Strö is very short (1-10 mm).
4. Sensor nach Anspruch 1, dadurch gekennzeichnet, daß der Sensor wegen der bes seren Biegesteifigkeit in beiden Seiten des Strömungs kanals ( Bild 1) gelagert ist. 4. Sensor according to claim 1, characterized in that the sensor because of the bes sera bending stiffness in both sides of the flow channel (Figure 1) is mounted.
5. Verfahren zur Optimierung der Maschinen- bzw. Werkzeug temperatureinstellung, dadurch gekennzeichnet, daß mit Hilfe eines Sensors nach den Ansprüchen 1-4 das tat sächliche Temperaturprofil vermessen wird und ein mög lichst flaches, radiales Temperaturprofil im Düsen- und Werkzeugbereich angestrebt wird. 5. A method of optimizing the machine or tool temperature setting, characterized in that with the aid of a sensor according to claims 1-4 that did neuter temperature profile is measured and a flat, radial temperature profile AS POSSIBLE in the nozzle and mold area is sought. Ergibt sich ein rela tives Maximum im Temperaturprofil hinter der Plastifi ziereinheit, so ist entweder die Wandtemperatur der Plastifiziereinheit zu erhöhen oder die zugeführte me chanische Energie (Drehzahl) zu verringern, was aber eine Durchsatzverminderung zur Folge hat. a rela tive maximum in the temperature profile after the plastifying results ornamental unit, then either to increase the wall temperature of the plasticizing unit or decrease the supplied me chanical energy (speed), but has a reduction in throughput result. Bei Auftreten eines relativen Maximums im Bereich der Extrusionswerkzeuge muß ebenfalls die Werkzeugtempera tur erhöht werden, wobei insbesondere überprüft werden sollte, ob das Temperaturprofil nicht schon hinter der Plastifiziereinheit vorlag. Upon occurrence of a relative maximum in the region of the extrusion dies, the tool also Tempera ture must be increased, which should be particularly checked whether the temperature profile was already available behind the plasticizing unit. Bei einem relativen Temperaturminimum ist entsprechend umgekehrt zu verfahren. At a relative minimum temperature is to process correspondingly reversed.
6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, daß eine Regelung, die das Ist- Temperaturprofil mit dementsprechenden, möglichst fla chen Soll-Temperaturprofil vergleicht, die entsprechen den Veränderungen der Maschineneinstellung automatisch vornimmt. 6. The method according to claim 5, characterized in that a system which compares the actual temperature profile with the corresponding, fla possible chen desired temperature profile that will automatically correspond to the variations of the machine setting makes.
7. Verfahren und Sensor nach Anspruch 1-6, dadurch gekennzeichnet, daß mit Hilfe der verbesserten Ortsauflösung der Temperaturmessung auch die thermische Homogenität der Schmelze (und damit auch näherungsweise die mechanische Homogenität) beurteilt werden kann. 7. The method and sensor according to claim 1-6, characterized in that the thermal homogeneity of the melt (and hence approximately the mechanical homogeneity) can be assessed using the improved spatial resolution of the temperature measurement.
DE19914129979 1991-09-10 1991-09-10 Temp. profile sensor for extruder nozzle or die - is shaped to suit specific task, carried in low conductivity material and can be used for manual or automatic optimisation of temp. control Withdrawn DE4129979A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE19914129979 DE4129979A1 (en) 1991-09-10 1991-09-10 Temp. profile sensor for extruder nozzle or die - is shaped to suit specific task, carried in low conductivity material and can be used for manual or automatic optimisation of temp. control
DE19914129978 DE4129978A1 (en) 1991-09-10 1991-09-10 Thermal values of plastics partic. at high cooling rates - are determined using sensor comprising small thermoelements mounted on surface of poor heat-conducting polyimide material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19914129979 DE4129979A1 (en) 1991-09-10 1991-09-10 Temp. profile sensor for extruder nozzle or die - is shaped to suit specific task, carried in low conductivity material and can be used for manual or automatic optimisation of temp. control

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2425621A1 (en) * 1974-05-27 1975-12-11 Demag Kunststofftech Injection molding machine
DE3313043C2 (en) * 1983-04-12 1987-11-05 Krauss-Maffei Ag, 8000 Muenchen, De
US4798692A (en) * 1984-07-11 1989-01-17 Robert Bosch Gmbh Method for controlling and/or regulating the injection molding in injection molding machines
DE3830571A1 (en) * 1987-09-08 1989-04-06 Toshiba Machine Co Ltd Method of calculation for flow analysis in injection moulding
DE3917523A1 (en) * 1989-05-30 1990-12-06 Beck Erich Dipl Ing Fh A process for traegheitslosen adjustment and stabilization of the melt temperature in the processing of thermoplastic materials

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2425621A1 (en) * 1974-05-27 1975-12-11 Demag Kunststofftech Injection molding machine
DE3313043C2 (en) * 1983-04-12 1987-11-05 Krauss-Maffei Ag, 8000 Muenchen, De
US4798692A (en) * 1984-07-11 1989-01-17 Robert Bosch Gmbh Method for controlling and/or regulating the injection molding in injection molding machines
DE3830571A1 (en) * 1987-09-08 1989-04-06 Toshiba Machine Co Ltd Method of calculation for flow analysis in injection moulding
DE3917523A1 (en) * 1989-05-30 1990-12-06 Beck Erich Dipl Ing Fh A process for traegheitslosen adjustment and stabilization of the melt temperature in the processing of thermoplastic materials

Non-Patent Citations (9)

* Cited by examiner, † Cited by third party
Title
BECK, E.: Durchsatz und Schmelzetemperatur beim Extrudieren gezielt einstellen. In: Kunststoffe 80, 1990, 6,S.667-672 *
CORNELY, J. *
et.al.: Messung von Druck u. Tempera-tur bei Spritzguß und Extrusion. In: Plaste und Kautschuk, 10.Jg., H.1/1963, S.51-58 *
GRÖMAR, Helmut *
LEEUWEN, J.: ENIGE ASPECTEN VAN DE BEHEERSING VAN *
PÜTZ, Helmut: Temperaturfühler mit erhöhter Meßgenauigkeit für Kunststoffverar- beitungsmaschinen. In: Kunststoffe 69, 1979, 9, S.588-590 *
Reges Interesse. In: Maschinenmarkt Würzburg 97, 1991, 20, S.150-154 *
SCHENKEL, Gerhard: Temeprtatur-Messungen in extru-dierten Strang-Erzeugnissen. In: Sonderdruck aus Kautschuk und Gummi - Kunststoffe, 19.Jg., 1966, H.4, S.213-217 *
WIEGAND, H.G.: Prozeßautomatisierung beim Extru- dieren und Spritzgießen von Kunststoffen, Carl Hanser Verlag München Wien 1979, S.23-26 *

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