EP1389403A1 - Heating element - Google Patents

Heating element

Info

Publication number
EP1389403A1
EP1389403A1 EP02730260A EP02730260A EP1389403A1 EP 1389403 A1 EP1389403 A1 EP 1389403A1 EP 02730260 A EP02730260 A EP 02730260A EP 02730260 A EP02730260 A EP 02730260A EP 1389403 A1 EP1389403 A1 EP 1389403A1
Authority
EP
European Patent Office
Prior art keywords
heating coil
heating element
tube
element according
heating
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Withdrawn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
EP02730260A
Other languages
German (de)
French (fr)
Inventor
Michael Hoffmann
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.)
Watlow GmbH
Original Assignee
Watlow GmbH
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 Watlow GmbH filed Critical Watlow GmbH
Publication of EP1389403A1 publication Critical patent/EP1389403A1/en
Withdrawn legal-status Critical Current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
    • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17—Component parts, details or accessories; Auxiliary operations
    • B29C45/26—Moulds
    • B29C45/27—Sprue channels ; Runner channels or runner nozzles
    • B29C45/2737—Heating or cooling means therefor
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/40—Heating elements having the shape of rods or tubes
    • H05B3/42—Heating elements having the shape of rods or tubes non-flexible
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/40—Heating elements having the shape of rods or tubes
    • H05B3/42—Heating elements having the shape of rods or tubes non-flexible
    • H05B3/44—Heating elements having the shape of rods or tubes non-flexible heating conductor arranged within rods or tubes of insulating material

Definitions

  • the invention relates to a heating element with a reflector tube, in which a heating coil having at least one resistance wire is arranged essentially coaxially, the heating coil being connectable to a power source via end connections and fastened in at least one holding section to the inner wall of the reflector tube.
  • a spray nozzle in plastics processing being assumed as an example below.
  • a sleeve-shaped heating element with an inner heating coil which is fastened to the inner wall of an outer reflector tube is pushed onto the outside of the nozzle.
  • the heating coil consists of a coiled jacket tube, which is usually made of stainless steel and in which one or more resistance wires are arranged along the entire length.
  • the resistance wires can be turned or straight. Lead wires are arranged at both ends of the resistance wire.
  • a heating coil with a connection outlet on both sides in which the connections of the resistance wire lie at opposite ends of the heating coil, the resistance wire is guided in one layer through the jacket tube.
  • the resistance wire is passed through the jacket tube in two layers or bifilar, or the jacket tube itself is wound in a double layer, with a bend at its end facing away from the connectors experienced by 180 °.
  • the resistance wires are embedded in a filler inside the jacket tube in order to achieve precise positioning and to avoid mutual contact.
  • the heating coil In order to achieve good heat transfer from the heating coil to the spray nozzle, the heating coil should lie tightly against the surface of the pointed nozzle. For this reason, it is known to slit the reflector tube in the longitudinal direction and on the outside with a clamping screw
  • the invention has for its object to provide a heating element of the type mentioned, which takes up little space and is easy to assemble on a nozzle.
  • the heating coil is free between the holding section in which it is fastened to the inner wall of the reflector tube and at least one axial end thereof, i.e. can be rotated without further attachment to the reflector tube and relative to it, and sits in the reflector tube with radial play and can be expanded radially by applying a torsional moment.
  • Game between the heating coil and the inner wall of the reflector tube and the at least partially free movement of the heating coil relative to the reflector tube make it possible to radially expand the heating coil in order to push it onto a nozzle without the reflector tube having to be slotted.
  • the expansion of the heating coil is made by manual application of a torsional moment, the fastening of the heating coil ensures on the inner wall of the Re ⁇ flektorrohres that the applied torsional - moment does not result in rotation of the heating coil, but to their expansion.
  • the heating coil After the heating coil is widened and pushed axially onto the nozzle, the application of the torsional moment is terminated, as a result of which the heating coil returns to its starting position and stretches radially from the outside onto the nozzle.
  • the resulting, radially inward spring force of the heating coil is dimensioned such that it also when the heating coil is heated and thus associated thermal expansions ensures that the heating coil contacts the nozzle.
  • the contact of the heating coil on the outer surface of the nozzle is achieved by the resilient restoring force of the heating coil, so that there is no need for an external clamping device and the heating element requires only a small installation space.
  • the heating coil is attached to the reflector tube in only a single holding section.
  • This holding section can be arranged, for example, in the central region of the heating coil, so that the two opposite axial sections of the heating coil pointing to different sides can be expanded independently of one another by applying a torsional moment to the respective end of the heating coil.
  • the holding section is arranged on or near only one axial end of the heating coil, so that a uniform radial expansion of the heating coil can be achieved over its entire length by applying a torsional moment, in particular at the other end of the heating coil. In this way, ei ⁇ ne simple operation of the heating element is ensured.
  • the resilience of the heating coil can be achieved on the one hand by the fact that the casing tube surrounding the contra-wire consists of a resilient material and in particular of a spring steel. Alternatively or additionally, it can be provided that a screw spring is integrated, which preferably also consists of a spring steel.
  • the helical spring runs essentially parallel to the casing tube and is coiled with it in a similar manner.
  • the helical spring is preferably fastened together with the casing tube in the same section to the inner wall of the reflector tube, the attachment being able to be achieved by an adhesive or welded connection.
  • the coil spring should be attached to the jacket tube at least in sections and in particular be welded on. This attachment ensures that the heating coil and the coil spring can only be expanded together and accordingly experience a common restoring force.
  • the heating coil is turned bifilar to form a one-sided outlet of the connections, i.e. from the end having the connections runs helically to the opposite end, there undergoes a 180 ° bend and runs helically back to the starting point, the two layers of the heating coil running parallel to one another.
  • a good and reliable attachment of the coil spring to the heating coil can be achieved if the coil spring is arranged between the two layers of the heating coil or the jacket tube and is attached to both layers.
  • the heating coil is attached at its end opposite the outlet end of the connections to the inner wall of the reflector tube. Applying a torsional moment to the outlet-side end of the connections thus leads to a radial expansion of the heating coil up to the fastening section, ie over almost its entire length.
  • the torsional moment required to expand the heating coil can be applied particularly easily by a user if the connections pass through the reflector tube at a recess running in the circumferential direction of the reflector tube. The user therefore only has to grasp the connections and move them along the recess in the circumferential direction of the reflector tube, which leads to the application of a torsional moment to the heating coil.
  • the recess on the one hand restricts the movement of the connections and prevents excessive deformation of the heating coil, on the other hand the recess also serves as a guide both when the heating coil is expanded and when it is resiliently reset.
  • FIG. 1 shows a longitudinal section through a heating element according to the invention in the starting position
  • FIG. 2 shows the heating element according to FIG. 1 in a position placed on a nozzle
  • FIG. 3 shows an external view of the heating element according to FIG. 1.
  • a heating element 10 shown in FIGS. 1 to 3 has a reflector tube 11, in the interior of which a heating coil 12 is arranged essentially coaxially.
  • the central longitudinal axis of the heating coil 12 essentially coincides with the central longitudinal axis of the reflector tube 11.
  • the heating coil 12 consists of a jacket tube 13, inside which a resistance wire 19 runs.
  • the jacket tube 13 is double-layered or bifilar, i.e. starting from a first axial end 12a of the heating coil 12 with a first end connection 15, the casing tube 13 extends in a coil section 13a to the opposite second axial end 12b of the heating coil 12, undergoes a 180 ° bend there and is in a second coil section 13b in similar spiral shape parallel to the first spiral section 13a to the exit area, ie the first axial end 12a of the heating coil 12, is returned and forms a second connection 16 there.
  • a helical spring 14 is inserted in a similar manner, which is connected to the outlet-side end of the connections 15 and 16 via a welded joint 17 two layers of the casing tube 13, ie is fastened to both spiral sections 13a and 13b.
  • the jacket tube 13 is fastened together with the coil spring 14 in a holding section 20 via a welded connection 18 to the inner wall 11a of the reflector tube 11.
  • connections 15 and 16 pass through the reflector tube 11 at a recess 11b running in the circumferential direction of the reflector tube 11, so that the connections 15 and 16 protrude on the outside and from a user relative to the Reflector tube 11 can be moved in its U direction, which leads to a torsional moment in the jacket tube 13 and the coil spring 14. Since the casing tube 13 is fastened together with the helical spring 14 at the end 12b of the heating coil 12 opposite the connections 15 and 16 via the welded connection 18 to the inner wall 11a of the reflector tube 11, the torsional moment leads to a radial expansion of the heating coil 12, which leads to this Purpose with radial play in the reflector tube 11.
  • the heating coil 12 After the user has radially expanded the heating coil 12, it can be pushed axially onto a nozzle D (see FIG. 2). When the user then releases the connections 15 and 16, the heating coil 12 returns from its radially widened position due to the spring action of the casing tube 13 and the coil spring 14 and in the process stretches radially from the outside onto the nozzle D, so that there is close contact between the jacket tube 13 and the outside of the nozzle D and thus a good heat transfer is ensured. This state is shown in Fig. 2.
  • the jacket tube has a circular cross section in the exemplary embodiment shown, other cross-sectional shapes, in particular a rectangular cross section, can also be used in order to achieve the largest possible contact area between the inside of the jacket tube and the outside surface of the nozzle D.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Resistance Heating (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)

Abstract

The invention relates to a heating element comprising an external reflector tube, in which a heating coil, including at least one resistance wire, is arranged substantially coaxially. Said heating coil can be connected to a current source by means of end side connectors and is secured to the inner wall of the reflector tube in at least one retaining section. According to the invention, said heating coil is free to move between the retaining section and at least a first axial end thereof. The heating coil is also mounted in the reflector tube with a radial clearance and may be radially expanded by application of a torsional moment. A jacket, enveloping the resistance wire, can be made from a spring material, especially a spring steel, and/or a helical spring can be integrated in said heating coil.

Description

Heizelement heating element
Die Erfindung betrifft ein Heizelement mit einem Reflektorrohr, in dem eine zumindest einen Widerstandsdraht aufweisende Heizwendel im wesentlichen koaxial angeordnet ist, wobei die Heizwendel über endseitige Anschlüsse an eine Stromquelle anschließbar und in zumindest einem Halteabschnitt an der Innenwandung des Reflektorrohrs befestigt ist .The invention relates to a heating element with a reflector tube, in which a heating coil having at least one resistance wire is arranged essentially coaxially, the heating coil being connectable to a power source via end connections and fastened in at least one holding section to the inner wall of the reflector tube.
In vielen Anwendungsbereichen der industriellen Fertigung ist es notwendig, eine Rohrleitung oder eine Düse auf einer erhöhten Temperatur zu erhalten, wobei im folgenden beispielhaft von einer Spritzdüse in der Kunststoffverarbeitung ausgegangen werden soll-. Aüßenseitig auf die Düse wird zu diesem Zweck ein hülsenförmiges Heizelement mit einer inneren Heizwendel aufgeschoben, die an der Innenwandung eines äußeren Reflektorrohres befestigt ist. Wenn die Heiz- wendel an eine Stromquelle angeschlossen und von elektrischem Strom durchflössen ist, wird ein Teil der elektri- sehen Energie in.Wärme umgesetzt, die auf die Düse übertragen wird. Die Heizwendel besteht aus einem gewendelten Mantelrohr, das in der Regel aus Edelstahl besteht und in dem ein oder mehrere Widerstandsdrähte über die gesamte Länge angeordnet sind. Die Widerstandsdrähte können dabei in sich gewendet oder auch gerade ausgebildet sein. An beiden Enden des Widerstandsdrahtes sind Anschlußlitzen angeordnet.In many areas of application in industrial production, it is necessary to maintain a pipeline or a nozzle at an elevated temperature, a spray nozzle in plastics processing being assumed as an example below. For this purpose, a sleeve-shaped heating element with an inner heating coil which is fastened to the inner wall of an outer reflector tube is pushed onto the outside of the nozzle. When the heating coil is connected to a power source and electrical current flows through it, part of the electrical energy is converted into heat which is transferred to the nozzle. The heating coil consists of a coiled jacket tube, which is usually made of stainless steel and in which one or more resistance wires are arranged along the entire length. The resistance wires can be turned or straight. Lead wires are arranged at both ends of the resistance wire.
Wenn eine Heizwendel mit beidseitigem Anschlußabgang vorgesehen ist, bei dem die Anschlüsse des Widerstandsdrahtes an entgegengesetzten Enden der Heizwendel liegen, wird der Widerstandsdraht einlagig durch das Mantelrohr geführt. Bei einem Heizelement mit einseitigem Anschlußabgang, bei dem die beiden Anschlüsse an demselben Ende der Heizwendel liegen, wird der Widerstandsdraht doppellagig bzw. bifilar durch das Mantelrohr geführt oder das Mantelrohr selbst wird doppellagig gewendelt, wobei es an seinem den An- Schlüssen abgewandten Ende eine Umbiegung um 180° erfährt. In allen Fällen sind die Widerstandsdrähte innerhalb des Mantelrohrs in einen Füllstoff eingebettet, um eine genaue Positionierung zu erreichen und einen gegenseitigen Kontakt zu vermeiden.If a heating coil with a connection outlet on both sides is provided, in which the connections of the resistance wire lie at opposite ends of the heating coil, the resistance wire is guided in one layer through the jacket tube. In the case of a heating element with a connection outlet on one side, in which the two connections are located at the same end of the heating coil, the resistance wire is passed through the jacket tube in two layers or bifilar, or the jacket tube itself is wound in a double layer, with a bend at its end facing away from the connectors experienced by 180 °. In all cases, the resistance wires are embedded in a filler inside the jacket tube in order to achieve precise positioning and to avoid mutual contact.
Um eine gute Wärmeübertragung von der Heizwendel auf die Spritzdüse zu erzielen, sollte die Heizwendel an der Oberfläche der Spitzdüse dicht anliegen. Aus diesem Grunde ist es bekannt, das Reflektorrohr in Längsrichtung zu schlitzen und außenseitig mit einer eine Spannschraube aufweisendenIn order to achieve good heat transfer from the heating coil to the spray nozzle, the heating coil should lie tightly against the surface of the pointed nozzle. For this reason, it is known to slit the reflector tube in the longitudinal direction and on the outside with a clamping screw
Spannvorrichtung zu versehen/, die das Reflektorrohr und damit die Heizwendel radial von außen gegen die Düse spannt. Mit dieser Ausgestaltung ist der Nachteil verbunden, daß die außenseitige Spannvorrichtung einen relativ großen Bau- räum benötigt und einen hohen Montageaufwand erfordert, insbesondere wenn in einem Vielfach-Düsen-Heizkanal 24 oder 36 oder mehr Düsen jeweils mit einem Heizelement versehen werden müssen. Der Erfindung liegt die Aufgabe zugrunde, ein Heizelement der genannten Art zu schaffen, das einen nur geringen Platzbedarf hat und in einfacher Weise auf einer Düse zu montierten ist.To provide clamping device / which clamps the reflector tube and thus the heating coil radially from the outside against the nozzle. This configuration has the disadvantage that the outside clamping device requires a relatively large amount of space and requires a large amount of installation work, in particular if 24 or 36 or more nozzles must be provided with a heating element in each case in a multiple nozzle heating duct. The invention has for its object to provide a heating element of the type mentioned, which takes up little space and is easy to assemble on a nozzle.
Diese Aufgabe wird erfindungsgemäß mit einem Heizelement mit den kennzeichnenden Merkmalen des Anspruchs 1 gelöst.This object is achieved with a heating element with the characterizing features of claim 1.
Erfindungsgemäß ist vorgesehen, daß die Heizwendel zwischen dem Halteabschnitt, in dem sie an der Innenwandung des Reflektorrohres befestigt ist, und zumindest ihrem einen axialen Ende frei, d.h. ohne weitere Befestigung am Reflektorrohr und relativ zu diesem verdrehbar, und mit radialem Spiel in dem Reflektorrohr sitzt und durch Aufbringung ei- nes Torsionsmomentes radial aufweitbar ist. Das radialeAccording to the invention it is provided that the heating coil is free between the holding section in which it is fastened to the inner wall of the reflector tube and at least one axial end thereof, i.e. can be rotated without further attachment to the reflector tube and relative to it, and sits in the reflector tube with radial play and can be expanded radially by applying a torsional moment. The radial
Spiel zwischen der Heizwendel und der Innenwandung des Reflektorrohrs und die zumindest abschnittsweise freie Beweglichkeit der Heizwendel relativ zu dem Reflektorrohr ermöglichen es, die Heizwendel radial aufzuweiten, um sie auf eine Düse aufzuschieben, ohne daß das Reflektorrohr geschlitzt sein muß. Die Aufweitung der Heizwendel erfolgt durch manuelle Aufbringung eines Torsionsmomentes, wobei die Befestigung der Heizwendel an der Innenwandung des Re¬ flektorrohres sicherstellt, daß das aufgebrachte Torsions - moment nicht zu einer Drehung der Heizwendel, sondern zu deren Aufweitung führt.Game between the heating coil and the inner wall of the reflector tube and the at least partially free movement of the heating coil relative to the reflector tube make it possible to radially expand the heating coil in order to push it onto a nozzle without the reflector tube having to be slotted. The expansion of the heating coil is made by manual application of a torsional moment, the fastening of the heating coil ensures on the inner wall of the Re ¬ flektorrohres that the applied torsional - moment does not result in rotation of the heating coil, but to their expansion.
Nachdem die Heizwendel aufgeweitet und auf die Düse axial aufgeschoben ist, wird die Aufbringung des Torsionsmomentes beendet, wodurch die Heizwendel in ihre Ausgangslage zurückkehrt und sich radial von außen auf die Düse spannt. Die sich dabei einstellende resultierende, radial nach innen gerichtete Federkraft der Heizwendel ist so bemessen, daß sie auch bei Erwärmung der Heizwendel und der damit verbundenen thermischen Dehnungen eine Anlage der Heizwendel an der Düse sicherstellt.After the heating coil is widened and pushed axially onto the nozzle, the application of the torsional moment is terminated, as a result of which the heating coil returns to its starting position and stretches radially from the outside onto the nozzle. The resulting, radially inward spring force of the heating coil is dimensioned such that it also when the heating coil is heated and thus associated thermal expansions ensures that the heating coil contacts the nozzle.
Erfindungsgemäß wird die Anlage der Heizwendel auf der Au- ßenoberfläche der Düse durch die federnde Rückstellkraft der Heizwendel erreicht, so daß auf eine außenseitige Spannvorrichtung verzichtet werden kann und das Heizelement einen nur geringen Bauraum benötigt . Darüber hinaus kann auf eine Schlitzung des Reflektorrohres verzichtet werden, wodurch die Herstellung des Heizelementes vereinfacht ist.According to the invention, the contact of the heating coil on the outer surface of the nozzle is achieved by the resilient restoring force of the heating coil, so that there is no need for an external clamping device and the heating element requires only a small installation space. In addition, there is no need to slit the reflector tube, which simplifies the manufacture of the heating element.
Um die Federspannung der Heizwendel über einen möglichst großen Bereich ihrer axialen Länge zu erhalten, ist in bevorzugter Ausgestaltung der Erfindung vorgesehen, daß die Heizwendel in nur einem einzigen Halteabschnitt am Reflektorrohr befestigt ist. Dieser Halteabschnitt kann beispielsweise im mittleren Bereich der Heizwendel angeordnet sein, so daß die beiden entgegengesetzten, zu verschiedenen Seiten weisenden axialen Abschnitte der Heizwendel unabhän- gig voneinander durch Aufbringung eines Torsionsmomentes an dem jeweiligen Ende der Heizwendel aufgeweitet werden können. Vorzugsweise ist jedoch vorgesehen, daß der Halteabschnitt an oder nahe nur einem axialen Ende der Heizwendel angeordnet ist, so daß durch Aufbringung eines Torsionsmo- mentes insbesondere am anderen Ende der Heizwendel eine gleichmäßige radiale Aufweitung der Heizwendel über ihre gesamte Länge erreicht werden kann. Auf diese Weise ist ei¬ ne einfache Bedienung des Heizelementes sichergestellt.In order to maintain the spring tension of the heating coil over the largest possible area of its axial length, it is provided in a preferred embodiment of the invention that the heating coil is attached to the reflector tube in only a single holding section. This holding section can be arranged, for example, in the central region of the heating coil, so that the two opposite axial sections of the heating coil pointing to different sides can be expanded independently of one another by applying a torsional moment to the respective end of the heating coil. However, it is preferably provided that the holding section is arranged on or near only one axial end of the heating coil, so that a uniform radial expansion of the heating coil can be achieved over its entire length by applying a torsional moment, in particular at the other end of the heating coil. In this way, ei ¬ ne simple operation of the heating element is ensured.
Die Federwirkung der Heizwendel kann einerseits dadurch erreicht werden, daß das den Widers andsdraht umgebende Mantelrohr aus einem federnden Material und insbesondere aus einem Federstahl besteht. Alternativ oder zusätzlich dazu kann vorgesehen sein, daß in die Heizwendel eine Schrauben- feder integriert ist, die vorzugsweise ebenfalls aus einem Federstahl besteht.The resilience of the heating coil can be achieved on the one hand by the fact that the casing tube surrounding the contra-wire consists of a resilient material and in particular of a spring steel. Alternatively or additionally, it can be provided that a screw spring is integrated, which preferably also consists of a spring steel.
In bevorzugter Ausgestaltung der Erfindung ist vorgesehen, daß die Schraubenfeder im wesentlichen parallel zu dem Mantelrohr verläuft und mit diesem in gleichartiger Weise ge- wendelt ist. Dabei ist die Schraubenfeder vorzugsweise zusammen mit dem Mantelrohr im gleichen Abschnitt an der Innenwandung des Reflektorrohres befestigt, wobei die Befe- stigung durch eine Kleb- oder Schweißverbindung erreicht werden kann.In a preferred embodiment of the invention it is provided that the helical spring runs essentially parallel to the casing tube and is coiled with it in a similar manner. The helical spring is preferably fastened together with the casing tube in the same section to the inner wall of the reflector tube, the attachment being able to be achieved by an adhesive or welded connection.
Um die Federwirkung der Schraubenfeder in vorteilhafter Weise auf die Heizwendel zu übertragen, sollte die Schrau- benfeder zumindest abschnittsweise an dem Mantelrohr befestigt und insbesondere angeschweißt sein. Diese Befestigung stellt sicher, daß die Heizwendel und die Schraubenfeder nur gemeinsam aufgeweitet werden können und entsprechend eine gemeinsame Rückstellkraft erfahren.In order to transfer the spring action of the coil spring to the heating coil in an advantageous manner, the coil spring should be attached to the jacket tube at least in sections and in particular be welded on. This attachment ensures that the heating coil and the coil spring can only be expanded together and accordingly experience a common restoring force.
In einer möglichen Ausgestaltung der Erfindung ist vorgesehen, daß die Heizwendel zur Bildung eines einseitigen Abgangs der Anschlüsse bifilar gewendet ist, d.h. von dem die Anschlüsse aufweisenden Ende wendeiförmig zu dem entgegen- gesetzten Ende verläuft, dort eine 180° -Umbiegung erfährt und wendeiförmig zum Ausgangspunkt zurückverläuft, wobei die beiden Lagen der Heizwendel parallel nebeneinander verlaufen. Eine gute und zuverlässige Befestigung der Schraubenfeder an der Heizwendel kann erreicht werden, wenn die Schraubenfeder zwischen den beiden Lagen der Heizwendel bzw. des Mantelrohres angeordnet und an beiden Lagen befestigt ist.In a possible embodiment of the invention it is provided that the heating coil is turned bifilar to form a one-sided outlet of the connections, i.e. from the end having the connections runs helically to the opposite end, there undergoes a 180 ° bend and runs helically back to the starting point, the two layers of the heating coil running parallel to one another. A good and reliable attachment of the coil spring to the heating coil can be achieved if the coil spring is arranged between the two layers of the heating coil or the jacket tube and is attached to both layers.
Um die Heizwendel über ihre gesamte Länge zuverlässig auf- weiten zu können, ist in Weiterbildung der Erfindung vorge- sehen, daß die Heizwendel an ihrem dem abgangsseitigen Ende der Anschlüsse entgegengesetzten Ende an der Innenwandung des Reflektorrohres befestigt ist. Eine Aufbringung eines Torsionsmomentes an dem abgangsseitigen Ende der Anschlüsse führt somit zu einer radialen Aufweitung der Heizwendel bis zu dem Befestigungsabschnitt, d.h. über annähernd ihre gesamte Länge.In order to be able to reliably expand the heating coil over its entire length, a further development of the invention see that the heating coil is attached at its end opposite the outlet end of the connections to the inner wall of the reflector tube. Applying a torsional moment to the outlet-side end of the connections thus leads to a radial expansion of the heating coil up to the fastening section, ie over almost its entire length.
Das zur Aufweitung der Heizwendel notwendige Torsionsmoment läßt sich von einem Benutzer besonders einfach aufbringen, wenn die Anschlüsse das Reflektorrohr an einer in Umfangs- richtung des Reflektorrohres verlaufenden Aussparung durchgreifen. Der Benutzer muß somit lediglich die Anschlüsse erfassen und in Umfangsrichtung des Reflektorrohres entlang der Aussparung bewegen, was zu der Aufbringung eines Torsionsmomentes auf die Heizwendel führt. Die Aussparung beschränkt dabei einerseits die Bewegung der Anschlüsse und verhindert eine übermäßige Verformung der Heizwendel, andererseits dient die Aussparung auch gleichzeitig als Führung sowohl bei der Aufweitung der Heizwendel als auch bei ihrer federnden Rückstellung.The torsional moment required to expand the heating coil can be applied particularly easily by a user if the connections pass through the reflector tube at a recess running in the circumferential direction of the reflector tube. The user therefore only has to grasp the connections and move them along the recess in the circumferential direction of the reflector tube, which leads to the application of a torsional moment to the heating coil. The recess on the one hand restricts the movement of the connections and prevents excessive deformation of the heating coil, on the other hand the recess also serves as a guide both when the heating coil is expanded and when it is resiliently reset.
Weitere Einzelheiten und Merkmale der Erfindung sind aus der folgenden Beschreibung eines Ausführungsbeispiels unter Bezugnahme auf die Zeichnung ersichtlich. Es zeigen:Further details and features of the invention are apparent from the following description of an embodiment with reference to the drawing. Show it:
Figur 1 einen Längsschnitt durch ein erfindungsgemäßes Heizelement in der Ausgangsstellung,FIG. 1 shows a longitudinal section through a heating element according to the invention in the starting position,
Figur 2 das Heizelement gemäß Fig. 1 in einer auf eine Düse aufgesetzten Stellung und2 shows the heating element according to FIG. 1 in a position placed on a nozzle and
Figur 3 eine Außenansicht des Heizelementes gemäß Fig. 1. Ein in den Fig. 1 bis 3 dargestelltes Heizelement 10 weist ein Reflektorrohr 11 auf, in dessen Innerem eine Heizwendel 12 im wesentlichen koaxial angeordnet ist. Die Mittellängs- achse der Heizwendel 12 fällt im wesentlichen mit der Mittellängsachse des Reflektorrohres 11 zusammen.3 shows an external view of the heating element according to FIG. 1. A heating element 10 shown in FIGS. 1 to 3 has a reflector tube 11, in the interior of which a heating coil 12 is arranged essentially coaxially. The central longitudinal axis of the heating coil 12 essentially coincides with the central longitudinal axis of the reflector tube 11.
Die Heizwendel 12 besteht aus einem Mantelrohr 13, in des- sem Inneren ein Widerstandsdraht 19 verläuft. Das Mantel - röhr 13 ist doppellagig bzw. bifilar gewendelt, d.h. ausgehend von einem ersten axialen Ende 12a der Heizwendel 12 mit einem ersten endseitigen Anschluß 15 verläuft das Mantelrohr 13 in einem Wendelabschnitt 13a bis zum entgegengesetzten zweiten axialen Ende 12b der Heizwendel 12, erfährt dort eine 180° -Umbiegung und wird in einem zweiten Wendelabschnitt 13b in gleichartig gewendelter Form parallel zum ersten Wendelabschnitt 13a zum Ausgangsbereich, d.h. dem ersten axialen Ende 12a der Heizwendel 12, zurückgeführt und bildet dort einen zweiten Anschluß 16. Zwischen die beiden Lagen des gewendelten Mantelrohres 13 ist eine in gleichartiger Weise gewendelte Schraubenfeder 14 eingelegt, die am abgangsseitigen Ende der Anschlüsse 15 und 16 über eine Schweißverbindung 17 an beiden Lagen des Mantelrohres 13, d.h. an beiden Wendelabschnitten 13a und 13b be- festigt ist. An dem dem abgangsseitigen Ende der AnschlüsseThe heating coil 12 consists of a jacket tube 13, inside which a resistance wire 19 runs. The jacket tube 13 is double-layered or bifilar, i.e. starting from a first axial end 12a of the heating coil 12 with a first end connection 15, the casing tube 13 extends in a coil section 13a to the opposite second axial end 12b of the heating coil 12, undergoes a 180 ° bend there and is in a second coil section 13b in similar spiral shape parallel to the first spiral section 13a to the exit area, ie the first axial end 12a of the heating coil 12, is returned and forms a second connection 16 there. Between the two layers of the coiled casing tube 13, a helical spring 14 is inserted in a similar manner, which is connected to the outlet-side end of the connections 15 and 16 via a welded joint 17 two layers of the casing tube 13, ie is fastened to both spiral sections 13a and 13b. At the end of the connections on the outlet side
15 und 16 entgegengesetzten Ende 12b der Heizwendel 12, d.h. im Bereich der 180° -Umbiegung des Mantelrohres 13, ist das Mantelrohr 13 zusammen mit der Schraubenfeder 14 in einem Halteabschnitt 20 über eine Schweißverbindung 18 an der Innenwandung 11a des Reflektorrohres 11 befestigt.15 and 16 opposite end 12b of the heating coil 12, i.e. in the region of the 180 ° bend of the jacket tube 13, the jacket tube 13 is fastened together with the coil spring 14 in a holding section 20 via a welded connection 18 to the inner wall 11a of the reflector tube 11.
Die Anschlüsse 15 und 16 durchgreifen das Reflektorrohr 11- an einer in Umfangsrichtung des Reflektorrohres 11 verlaufenden Aussparung 11b, so daß die Anschlüsse 15 und 16 au- ßenseitig hervorstehen und von einem Benutzer relativ zum Reflektorrohr 11 in dessen U fangsrichtung bewegt werden können, was zu einem Torsionsmoment in dem Mantelrohr 13 und der Schraubenfeder 14 führt. Da das Mantelrohr 13 zusammen mit der Schraubenfeder 14 an dem den Anschlüssen 15 und 16 entgegengesetzten Ende 12b der Heizwendel 12 über die Schweißverbindung 18 an der Innenwandung 11a des Reflektorrohres 11 befestigt ist, führt das Torsionsmoment zu einer radialen AufWeitung der Heizwendel 12, die zu diesem Zweck unter radialem Spiel in dem Reflektorrohr 11 aufge- nommen ist. Nachdem der Benutzer die Heizwendel 12 radial aufgeweitet hat, kann diese auf eine Düse D axial aufgeschoben werden (siehe Fig. 2) . Wenn der Benutzer dann die Anschlüsse 15 und 16 losläßt, kehrt die Heizwendel 12 aufgrund der Federwirkung des Mantelrohres 13 und der Schrau- benfeder 14 aus ihrer radial aufgeweiteten Lage zurück und spannt sich dabei radial von außen auf die Düse D, so daß ein enger Kontakt zwischen dem Mantelrohr 13 und der Außenseite der Düse D und somit ein guter Wärmeübergang sichergestellt ist. Dieser Zustand ist in Fig. 2 dargestellt.The connections 15 and 16 pass through the reflector tube 11 at a recess 11b running in the circumferential direction of the reflector tube 11, so that the connections 15 and 16 protrude on the outside and from a user relative to the Reflector tube 11 can be moved in its U direction, which leads to a torsional moment in the jacket tube 13 and the coil spring 14. Since the casing tube 13 is fastened together with the helical spring 14 at the end 12b of the heating coil 12 opposite the connections 15 and 16 via the welded connection 18 to the inner wall 11a of the reflector tube 11, the torsional moment leads to a radial expansion of the heating coil 12, which leads to this Purpose with radial play in the reflector tube 11. After the user has radially expanded the heating coil 12, it can be pushed axially onto a nozzle D (see FIG. 2). When the user then releases the connections 15 and 16, the heating coil 12 returns from its radially widened position due to the spring action of the casing tube 13 and the coil spring 14 and in the process stretches radially from the outside onto the nozzle D, so that there is close contact between the jacket tube 13 and the outside of the nozzle D and thus a good heat transfer is ensured. This state is shown in Fig. 2.
Obwohl das Mantelrohr im dargestellten Ausführungsbeispiel einen Kreisquerschnitt hat, können auch andere Quer- schnittsformen, insbesondere ein Rechteckquerschnitt Verwendung finden, um eine möglichst große Kontaktfläche zwi- sehen der Innenseite des Mantelrohres und der Außenoberfläche der Düse D zu erreichen. Although the jacket tube has a circular cross section in the exemplary embodiment shown, other cross-sectional shapes, in particular a rectangular cross section, can also be used in order to achieve the largest possible contact area between the inside of the jacket tube and the outside surface of the nozzle D.

Claims

Patentansprüche claims
1. Heizelement mit einem Reflektorrohr (11), in dem eine zumindest einen Widerstandsdraht (19) aufweisende Heizwendel (12) im wesentlichen koaxial angeordnet ist, wobei die Heizwendel (12) über endseitige Anschlüsse (15,16) an eine Stromquelle anschließbar und in zumindest einem Halteabschnitt (20) an der Innenwandung (11a) das Reflektorrohres (11) befestigt ist, dadurch gekennzeichnet, daß die Heizwendel (12) zwi- sehen dem Halteabschnitt (20) und zumindest ihrem einem axialen Ende (12a) frei und mit radialem Spiel in dem Reflektorrohr (11) sitzt und durch Aufbringung eines Torsionsmomentes radial aufweitbar ist.1. Heating element with a reflector tube (11), in which a heating coil (12) having at least one resistance wire (19) is arranged essentially coaxially, the heating coil (12) being connectable to a power source via end connections (15, 16) and in At least one holding section (20) is attached to the inner wall (11a) of the reflector tube (11), characterized in that the heating coil (12) between the holding section (20) and at least its one axial end (12a) is free and with a radial Game sits in the reflector tube (11) and can be expanded radially by applying a torsional moment.
2. Heizelement nach Anspruch 1, dadurch gekennzeichnet, daß die Heizwendel (12) in nur einem Halteabschnitt (20) am Reflektorrohr (11) befestigt ist.2. Heating element according to claim 1, characterized in that the heating coil (12) is attached to the reflector tube (11) in only one holding section (20).
3. Heizelement nach Anspruch 1 oder 2, dadurch gekenn- zeichnet, daß der Halteabschnitt (20) an oder nahe einem axialen Ende (12b) der Heizwendel (12) angeordnet ist .3. Heating element according to claim 1 or 2, characterized in that the holding section (20) at or near an axial end (12b) of the heating coil (12) is arranged is.
4. Heizelement nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Heizwendel (12) ein den Wider- Standsdraht (19) umgebendes Mantelrohr (13) aus einem federnden Material und insbesondere aus einem Federstahl besitzt.4. Heating element according to one of claims 1 to 3, characterized in that the heating coil (12) has a sheath tube (13) surrounding the resistance wire (19) made of a resilient material and in particular of a spring steel.
5. Heizelement nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß in die Heizwendel (12) eine5. Heating element according to one of claims 1 to 4, characterized in that in the heating coil (12)
Schraubenfeder (14) integriert ist.Coil spring (14) is integrated.
6. Heizelement nach Anspruch 5, dadurch gekennzeichnet, daß die Schraubenfeder (14) im wesentlichen parallel zu dem Mantelrohr (13) verläuft.6. Heating element according to claim 5, characterized in that the helical spring (14) extends substantially parallel to the casing tube (13).
7. Heizelement nach Anspruch 5 oder 6, dadurch gekennzeichnet, daß die Schraubenfeder (14) zusammen mit dem Mantelrohr (13) an der Innenwandung (11a) des Reflek- torrohrs (11) befestigt ist.7. Heating element according to claim 5 or 6, characterized in that the helical spring (14) together with the casing tube (13) on the inner wall (11 a) of the reflector tube (11) is attached.
8. Heizelement nach einem der Ansprüche 5 bis 7, dadurch gekennzeichnet, daß die Schraubenfeder (14) zumindest abschnittsweise an dem Mantelrohr (13) befestigt ist.8. Heating element according to one of claims 5 to 7, characterized in that the coil spring (14) is attached at least in sections to the casing tube (13).
9. Heizelement nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, daß die Heizwendel (12) zur Bildung eines einseitigen Abgangs der Anschlüsse (15,16) bifilar gewendelt ist.9. Heating element according to one of claims 1 to 8, characterized in that the heating coil (12) is wound bifilar to form a one-sided outlet of the connections (15, 16).
10. Heizelement nach Anspruch 9, dadurch gekennzeichnet, daß die Schraubenfeder (14) zwischen den beiden Lagen der Heizwendel (12) angeordnet ist. 10. Heating element according to claim 9, characterized in that the helical spring (14) is arranged between the two layers of the heating coil (12).
11. Heizelement nach Anspruch 9 oder 10, dadurch gekennzeichnet, daß die Heizwendel (12) an ihrem dem abgangsseitigen Ende der Anschlüsse (15,16) entgegengesetzten Ende (12b) an der Innenwandung (11a) des Re- flektorrohrs (11) befestigt ist.11. Heating element according to claim 9 or 10, characterized in that the heating coil (12) is attached at its end (12b) opposite the outlet-side end of the connections (15, 16) to the inner wall (11a) of the reflector tube (11) ,
12. Heizelement nach einem der Ansprüche 1 bis 11, dadurch gekennzeichnet, daß die Anschlüsse (15,16) das Reflektorrohr (11) an einer in U fangsrichtung des Refle - torrohrs (11) verlaufenden Aussparung (11b) durchgreifen. 12. Heating element according to one of claims 1 to 11, characterized in that the connections (15, 16) pass through the reflector tube (11) at a recess (11b) running in the U direction of the reflector tube (11).
EP02730260A 2001-05-21 2002-05-16 Heating element Withdrawn EP1389403A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10124960 2001-05-21
DE2001124960 DE10124960A1 (en) 2001-05-21 2001-05-21 Heating element for heating pipes or nozzles in industrial manufacturing has heating coil that sits in reflector tube with radial play and is attached in one section to reflector tube inner wall
PCT/EP2002/005399 WO2002096156A1 (en) 2001-05-21 2002-05-16 Heating element

Publications (1)

Publication Number Publication Date
EP1389403A1 true EP1389403A1 (en) 2004-02-18

Family

ID=7685751

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02730260A Withdrawn EP1389403A1 (en) 2001-05-21 2002-05-16 Heating element

Country Status (3)

Country Link
EP (1) EP1389403A1 (en)
DE (1) DE10124960A1 (en)
WO (1) WO2002096156A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004007542B4 (en) * 2004-02-15 2007-03-22 Gc-Heat Gebhard & Castiglia Gmbh & Co. Kg Electric radiator in the form of a compressed heating element with permanent spring properties
EP1819201B1 (en) * 2006-02-08 2008-08-20 Hotset Heizpatronen u. Zubehör GmbH Heating device for cylindrical pieces
DE202008015979U1 (en) 2008-12-03 2010-05-06 Türk & Hillinger GmbH Tubular heating element

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2022124A1 (en) * 1990-07-27 1992-01-28 Jobst Ulrich Gellert Insulated injection molding nozzle
DE19502327A1 (en) * 1994-03-16 1995-09-21 Hotset Heizpatronen Zubehoer Heatable cylinder esp. injection moulding tube or mandrel
DE19535472A1 (en) * 1995-09-23 1997-03-27 Tuerk & Hillinger Gmbh Electrical ring heating member e.g. for heating components with round cross-section
DE19538205C1 (en) * 1995-10-13 1997-02-13 Hotset Heizpatronen Zubehoer Tubular electrical heating element
DE19746311C2 (en) * 1997-10-21 2000-05-31 Hotset Heizpatronen Zubehoer Electric heating cartridge
DE19746556A1 (en) * 1997-10-22 1999-05-06 Hotset Heizpatronen Zubehoer Heating element for making injection moulding products
DE19943192A1 (en) * 1999-09-09 2001-04-05 Hotset Heizpatronen Zubehoer Tubular heating element
DE29918251U1 (en) * 1999-10-18 1999-12-23 Otto Maenner Vertriebs Gmbh Fa Hot runner nozzle

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO02096156A1 *

Also Published As

Publication number Publication date
WO2002096156A1 (en) 2002-11-28
DE10124960A1 (en) 2002-11-28

Similar Documents

Publication Publication Date Title
EP1748679B1 (en) Pressurized heating cartridge
DE2849266A1 (en) ELECTRIC RADIATOR FOR FLUID MEDIA
DE202010006739U1 (en) Heater
DE19806906A1 (en) Connection element for a coaxial high-frequency cable
DE2949174A1 (en) MECHANICAL AND / OR ELECTRICAL CONNECTION BETWEEN LONG-TERM COMPONENTS AND DEVICE AND METHOD FOR THEIR PRODUCTION
CH685403A5 (en) Molding of thermoplastic material.
DE102016121571A1 (en) Heat-conducting body for a nozzle heater and nozzle heater
DE2901420C2 (en) Radiators for electric warm air devices
DE19746556A1 (en) Heating element for making injection moulding products
EP3883338A1 (en) Compact heater with sheathed tubular heating element
EP1389403A1 (en) Heating element
EP0123698A1 (en) Electric heating element for heating a fluid
DE2042183C3 (en)
DE19628773A1 (en) Heat exchanger for hot water preparation
DE202010011405U1 (en) Heating device with temperature sensor
DE2705526C3 (en) Electric heating element for gaseous media
DE2939933C2 (en) Cable set with metallic housing
DE2500622C3 (en) Electric heating element
DE102022127109A1 (en) Tubular electrical heater and system of tubular electrical heater and object to be heated
EP2194753B1 (en) Tubular heating element
EP1519629B1 (en) Electrical heater for the heating of flowing gaseous medium and method for the production thereof
DE3935054C2 (en)
DE102017112328B4 (en) Electric heater
EP3130441B1 (en) Connector and method of manufacturing a connector
DE19711632A1 (en) Liquid cooled power resistance

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20031126

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

17Q First examination report despatched

Effective date: 20040310

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20090620