EP0090676B1 - Method and devices for regulating the mean induced heating power in a flat conductive product maintained in position electromagnetically without contact - Google Patents
Method and devices for regulating the mean induced heating power in a flat conductive product maintained in position electromagnetically without contact Download PDFInfo
- Publication number
- EP0090676B1 EP0090676B1 EP83400258A EP83400258A EP0090676B1 EP 0090676 B1 EP0090676 B1 EP 0090676B1 EP 83400258 A EP83400258 A EP 83400258A EP 83400258 A EP83400258 A EP 83400258A EP 0090676 B1 EP0090676 B1 EP 0090676B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- poles
- induced
- product
- power
- inductors
- 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
Links
- 238000010438 heat treatment Methods 0.000 title claims description 21
- 238000000034 method Methods 0.000 title claims description 13
- 230000001105 regulatory effect Effects 0.000 title 1
- 238000009434 installation Methods 0.000 claims description 5
- 230000005672 electromagnetic field Effects 0.000 claims description 3
- 230000005674 electromagnetic induction Effects 0.000 claims description 3
- 125000004122 cyclic group Chemical group 0.000 claims description 2
- 230000003068 static effect Effects 0.000 claims description 2
- 238000009827 uniform distribution Methods 0.000 claims description 2
- 238000005339 levitation Methods 0.000 description 11
- 230000004907 flux Effects 0.000 description 2
- 239000000470 constituent Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
Images
Classifications
-
- 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
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
- H05B6/101—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces
- H05B6/103—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces multiple metal pieces successively being moved close to the inductor
- H05B6/104—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces multiple metal pieces successively being moved close to the inductor metal pieces being elongated like wires or bands
-
- 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
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/06—Control, e.g. of temperature, of power
Definitions
- the present invention relates to a method and to devices for implementing this method allowing the adjustment of the average heating power induced by an electromagnetic field in a flat conductive product when stopped or running, maintained without contact, by the electromagnetic forces also induced by this field, in particular in levitation or guidance, in an electromagnetic induction heating installation comprising a pair of substantially identical inductors whose poles face each other in pairs on either side of the product.
- the object of the invention is to regulate in the widest possible range the heating power induced in a flat conductive product maintained without contact, by the correspondingly induced electromagnetic forces, in particular in levitation or guidance, by ensuring the product a substantially constant position. and using simple and economical equipment.
- the method according to the invention consists, for adjusting the heating power induced by an electromagnetic field in a flat conductive product maintained without contact by the electromagnetic forces correlatively induced by this field, in an electromagnetic induction heating installation comprising a pair of substantially identical inductors, arranged on either side of the product, the poles of one of the inductors of the pair facing the poles of the other inductor, to operate a series of reversals of the instantaneous polarity of the poles of the one of the inductors with respect to the instantaneous polarity of the corresponding poles of the other inductor, the ratio of the durations during which the polarities are on the one hand opposite and on the other hand identical determining the average value of the induced heating power, the position of the product remaining almost unchanged.
- the electromagnetic forces exerted on the product and which maintain it without contact remain substantially the same, that the instantaneous polarities of the poles two by two face to face of the inductors are all identical or all opposite, all other things remaining equal, if although during a reversal of the relative polarity of the poles of one of the inductors with respect to the polarity of the corresponding poles of the other inductor, the position of the product remains almost unchanged.
- the invention applies in particular to heating installations in levitation or, for example, heating with guidance for which it is necessary to maintain restoring forces, of substantially constant intensity, towards an equilibrium position.
- the instantaneous polarity inversions of the poles of one of the inductors with respect to the instantaneous polarity of the corresponding poles of the other inductor are carried out by the polarity reverser which operates for example an inversion of the connection of one of the inductors to the alternative source of current or voltage (the voltage / current ratio is different depending on whether the polarities are identical or opposite).
- a device comprises in one embodiment, a duty cycle generator whose frequency is a function of the desired adjustment precision, this in order to allow rigorously following an imposed temperature curve as a function of time.
- the polarity reverser is of the static type, consisting of two rectifier bridges in anti-parallel mounting.
- the adjustment device further comprises interposed between the adjustment system (C) and the inverter (A), a duty cycle generator (B) whose frequency is a function of the desired adjustment precision.
- This arrangement makes it possible, in particular, to rigorously follow an imposed temperature curve as a function of time.
- the polarity reverser (A) consists of two rectifier bridges in anti-parallel mounting, but this choice is in no way limiting.
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- General Induction Heating (AREA)
Description
La présente invention se rapporte à un procédé et à des dispositifs de mise en oeuvre de ce procédé permettant le réglage de la puissance moyenne de chauffage induite par un champ élec- tromagnétiqué dans un produit plat conducteur à l'arrêt ou en défilement, maintenu sans contact, par les forces électromagnétiques également induites par ce champ, notamment en lévitation ou guidage, dans une installation de chauffage par induction électromagnétique comprenant une paire d'inducteurs sensiblement identiques dont les pôles se font face deux à deux de part et d'autre du produit.The present invention relates to a method and to devices for implementing this method allowing the adjustment of the average heating power induced by an electromagnetic field in a flat conductive product when stopped or running, maintained without contact, by the electromagnetic forces also induced by this field, in particular in levitation or guidance, in an electromagnetic induction heating installation comprising a pair of substantially identical inductors whose poles face each other in pairs on either side of the product.
Dans diverses opérations de parachèvement et spécialement dans certains traitements thermiques, il peut être nécessaire de régler la puissance induite dans un produit maintenu sans contact, par exemple en lévitation, afin de suivre une courbe imposée de température en fonction du temps.In various finishing operations and especially in certain heat treatments, it may be necessary to adjust the power induced in a product maintained without contact, for example in levitation, in order to follow an imposed temperature curve as a function of time.
Dans le document EP-A-0 070 232 appartenant à l'état de la technique selon l'art. 54(3) de la CBE, on décrit une installation de chauffage d'un produit métallique en lévitation. Le chauffage et la lévitation sont obtenus par un flux électromagnétique transversal provenant de deux jeux de pôles d'inducteur. Les inducteurs sont disposés de part et d'autre du produit et sont alimentés en courant alternatif de telle sorte que deux pôles en face l'un de l'autre sont à tout instant polarisés inversé- ment.In document EP-A-0 070 232 belonging to the state of the art according to art. 54 (3) of the EPC, an installation for heating a levitated metal product is described. Heating and levitation are obtained by a transverse electromagnetic flux from two sets of inductor poles. The inductors are arranged on either side of the product and are supplied with alternating current so that two poles opposite one another are polarized inversely at all times.
Il est évident que pour réduire la puissance induite dans un produit soumis à un flux transversal, on peut se contenter de diminuer l'intensité du courant parcourant les inducteurs, mais, lorsque le produit est en lévitation, cette réduction entraîne généralement une diminution de la hauteur de lévitation. De plus, lorsque l'on veut maintenir le produit sans contact, la réduction de puissance est limitée par la nécessité de maintenir la hauteur de lévitation à une valeur minimale.It is obvious that in order to reduce the power induced in a product subjected to a transverse flux, it is sufficient to reduce the intensity of the current flowing through the inductors, but, when the product is in levitation, this reduction generally results in a reduction in the levitation height. In addition, when it is desired to maintain the product without contact, the reduction in power is limited by the need to keep the levitation height at a minimum value.
On connaît aussi, par le document EP-A-0087345 appartenant également à l'état de la technique selon l'art 54(3) de la CBE, un dispositif similaire qui ne se distingue du précédent que par une alimentation «en phase» des paires de pôles. Ainsi, on obtient une lévitation sans chauffage notable.Also known, from document EP-A-0087345 also belonging to the state of the art according to art 54 (3) of the EPC, a similar device which differs from the previous one only by a "phase" supply pairs of poles. Thus, a levitation is obtained without significant heating.
Le but de l'invention est de régler dans la plus large plage possible la puissance de chauffage induite dans un produit plat conducteur maintenu sans contact, par les forces électromagnétiques corrélativement induites, notamment en lévitation ou guidage, en assurant au produit une position sensiblement constante et en utilisant un appareillage simple et économique.The object of the invention is to regulate in the widest possible range the heating power induced in a flat conductive product maintained without contact, by the correspondingly induced electromagnetic forces, in particular in levitation or guidance, by ensuring the product a substantially constant position. and using simple and economical equipment.
Le procédé selon l'invention consiste, pour régler la puissance de chauffage induite par un champ électromagnétique dans un produit plat conducteur maintenu sans contact par les forces électromagnétiques corrélativement induites par ce champ, dans une installation de chauffage par induction électromagnétique comprenant une paire d'inducteurs sensiblement identiques, disposés de part et d'autre du produit, les pôles de l'un des inducteurs de la paire faisant face aux pôles de l'autre inducteur, à opérer une suite d'inversions de la polarité instantanée des pôles de l'un des inducteurs par rapport à la polarité instantanée des pôles correspondants de l'autre inducteur, le rapport des durées pendant lesquelles les polarités sont d'une part opposées et d'autre part identiques déterminant la valeur moyenne de la puissance de chauffage induite, la position du produit restant quasiment inchangée.The method according to the invention consists, for adjusting the heating power induced by an electromagnetic field in a flat conductive product maintained without contact by the electromagnetic forces correlatively induced by this field, in an electromagnetic induction heating installation comprising a pair of substantially identical inductors, arranged on either side of the product, the poles of one of the inductors of the pair facing the poles of the other inductor, to operate a series of reversals of the instantaneous polarity of the poles of the one of the inductors with respect to the instantaneous polarity of the corresponding poles of the other inductor, the ratio of the durations during which the polarities are on the one hand opposite and on the other hand identical determining the average value of the induced heating power, the position of the product remaining almost unchanged.
En effet, les forces électromagnétiques exercées sur le produit et qui le maintiennent sans contact restent sensiblement les mêmes, que les polarités instantanées des pôles deux à deux face à face des inducteurs soient toutes identiques ou toutes opposées, toutes choses restant égales par ailleurs, si bien que lors d'une inversion de la polarité relative des pôles de l'un des inducteurs par rapport à la polarité des pôles correspondants de l'autre inducteur, la position du produit reste quasiment inchangée.Indeed, the electromagnetic forces exerted on the product and which maintain it without contact remain substantially the same, that the instantaneous polarities of the poles two by two face to face of the inductors are all identical or all opposite, all other things remaining equal, if although during a reversal of the relative polarity of the poles of one of the inductors with respect to the polarity of the corresponding poles of the other inductor, the position of the product remains almost unchanged.
Ainsi on obtient par la commutation cyclique de l'inverseur tantôt une lévitation seule et tantôt la même lévitation en combinaison avec un chauffage du produit. Le rapport de commutation définit donc le taux de chauffage alors que l'intensité de courant reste constante.Thus, by cyclic switching of the inverter, there is sometimes a levitation alone and sometimes the same levitation in combination with heating of the product. The switching ratio therefore defines the heating rate while the current intensity remains constant.
Un des avantages du procédé selon l'invention ressort du fait que les distances séparant les surfaces polaires de chaque paire de pôles se faisant face de part et d'autre du produit, peuvent être réduites au minimum correspondant à l'espace nécessaire à l'encombrement total en épaisseur du produit compte tenu de ses déformations et d'une éventuelle isolation thermique, le jeu assurant l'absence de contact étant presque nul. Le rendement et le facteur de puissance des dispositifs mettant en oeuvre ce procédé en sont donc améliorés.One of the advantages of the method according to the invention is apparent from the fact that the distances separating the pole surfaces of each pair of poles facing each other on either side of the product can be reduced to the minimum corresponding to the space necessary for the total overall thickness of the product taking into account its deformations and possible thermal insulation, the clearance ensuring the absence of contact being almost zero. The efficiency and the power factor of the devices implementing this process are therefore improved.
Ce procédé simple et économique, s'applique en particulier à la réduction de la puissance induite en fin de chauffage. Les écarts de température dynamiques étant proportionnels à la puissance volumique induite et résultant, à la fois, des phénomènes de conduction et d'une répartition non parfaitement uniforme des densités de courant induites, cette réduction de puissance permet d'obtenir des écarts de température dynamiques plus faibles et donc, par exemple, d'atteindre une température moyenne dans le produit sans dépassement local de la température limite à respecter.This simple and economical process applies in particular to the reduction of the power induced at the end of heating. Since the dynamic temperature differences are proportional to the power density induced and resulting, at the same time, from conduction phenomena and from a non-perfectly uniform distribution of the induced current densities, this reduction in power makes it possible to obtain dynamic temperature differences lower and therefore, for example, to reach an average temperature in the product without locally exceeding the limit temperature to be observed.
L'invention s'applique notamment à des installations de chauffage en lévitation ou, par exemple, de chauffage avec guidage pour lesquels il est nécessaire de maintenir des forces de rappel, d'intensité sensiblement constante, vers une position d'équilibre.The invention applies in particular to heating installations in levitation or, for example, heating with guidance for which it is necessary to maintain restoring forces, of substantially constant intensity, towards an equilibrium position.
L'invention vise également des dispositifs de réglage de la puissance moyenne induite dans un produit plat conducteur maintenu sans contact dans une position sensiblement constante par les forces électromagnétiques corrélativement induites, lesquels dispositifs mettent en oeuvre le procédé selon l'invention et se caractérisent en ce qu'ils comprennent nécessairement un moyen inverseur de polarité et, en outre, et suivant les cas:
- - un système de réglage;
- - des moyens permettant de connaître la température du produit;
- - des moyens permettant de connaître la puissance induite;
- - des moyens permettant de définir le cycle de puissance à injecter;
- - des moyens permettant de définir le cycle de température à effectuer;
les informations, résultats et données obtenus de ces moyens ainsi que les caractéristiques du produit étant pris en compte par ledit système de réglage.The invention also relates to devices for adjusting the average power induced in a flat conductive product maintained without contact in a substantially constant position by the correlatively induced electromagnetic forces, which devices implement the pro assigned according to the invention and are characterized in that they necessarily include a polarity reversing means and, moreover, and depending on the case:
- - an adjustment system;
- - means for determining the temperature of the product;
- - means allowing to know the induced power;
- - means for defining the power cycle to be injected;
- - means for defining the temperature cycle to be performed;
the information, results and data obtained from these means as well as the characteristics of the product being taken into account by said adjustment system.
Les inversions de polarité instantanée des pôles de l'un des inducteurs par rapport à la polarité instantanée des pôles correspondants de l'autre inducteur sont effectuées par l'inverseur de polarité qui opère par exemple une inversion du branchement de l'un des inducteurs à la source alternative de courant ou de tension (le rapport ten- sion/courant est différent selon que les polarités sont identiques ou opposées).The instantaneous polarity inversions of the poles of one of the inductors with respect to the instantaneous polarity of the corresponding poles of the other inductor are carried out by the polarity reverser which operates for example an inversion of the connection of one of the inductors to the alternative source of current or voltage (the voltage / current ratio is different depending on whether the polarities are identical or opposite).
Un dispositif selon l'invention comprend dans une forme de réalisation, un générateur de rapport cyclique dont la fréquence est fonction de la précision de réglage recherchée, ceci afin de permettre de suivre de façon rigoureuse une courbe imposée de température en fonction du temps.A device according to the invention comprises in one embodiment, a duty cycle generator whose frequency is a function of the desired adjustment precision, this in order to allow rigorously following an imposed temperature curve as a function of time.
Dans une forme préférée de réalisation, l'inverseur de polarité est de type statique, constitué de deux ponts de redresseurs en montage anti-parallèle.In a preferred embodiment, the polarity reverser is of the static type, consisting of two rectifier bridges in anti-parallel mounting.
Les caractéristiques et avantages de la présente invention ressortiront mieux de la description qui va suivre faite en regard du dessin annexé dont la figure unique est un organigramme de fonctionnement de dispositifs selon l'invention.The characteristics and advantages of the present invention will emerge more clearly from the description which follows, given with regard to the appended drawing, the single figure of which is an operating flow diagram of devices according to the invention.
Un dispositif de mise en oeuvre du procédé selon l'invention comprend:
- - nécessairement, un moyen inverseur (A) permettant d'opérer une suite d'inversions de la polarité instantanée des pôles de l'un des inducteurs de la paire par rapport à la polarité instantanée des pôles correspondants de l'autre inducteur et, suivant les cas:
- - un système de réglage (C) électronique de préférence;
- - des moyens (D) permettant de connaître la température du produit;
- - des moyens (E) permettant de connaître la puissance induite;
- - des moyens (F) permettant de définir le cycle de puissance à injecter;
- -des moyens (G) permettant de définir le cycle de température à effectuer;
les informations, résultats et données obtenus de ces moyens ainsi que les caractéristiques du produit (H) étant pris en compte par ledit système de réglage (C).A device for implementing the method according to the invention comprises:
- - necessarily, an inverting means (A) making it possible to operate a series of inversions of the instantaneous polarity of the poles of one of the inductors of the pair with respect to the instantaneous polarity of the corresponding poles of the other inductor and, according to cases:
- - an electronic adjustment system (C) preferably;
- - means (D) for knowing the temperature of the product;
- - means (E) making it possible to know the induced power;
- - means (F) for defining the power cycle to be injected;
- means (G) making it possible to define the temperature cycle to be carried out;
the information, results and data obtained from these means as well as the characteristics of the product (H) being taken into account by said adjustment system (C).
Selon une forme de réalisation dont une partie est représentée en pointillés sur la figure unique du dessin annexé, le dispositif de réglage selon l'invention comprend, de plus, intercalé entre le système de réglage (C) et l'inverseur (A), un générateur de rapport cyclique (B) dont la fréquence est fonction de la précision de réglage recherchée. Cette disposition permet, en particulier, de suivre de façon rigoureuse une courbe imposée de température en fonction du temps.According to one embodiment, part of which is shown in dotted lines in the single figure of the appended drawing, the adjustment device according to the invention further comprises interposed between the adjustment system (C) and the inverter (A), a duty cycle generator (B) whose frequency is a function of the desired adjustment precision. This arrangement makes it possible, in particular, to rigorously follow an imposed temperature curve as a function of time.
Suivant une forme de réalisation l'inverseur de polarité (A) est constitué de deux ponts de redresseurs en montage anti-parallèle, mais ce choix n'est nullement limitatif.According to one embodiment the polarity reverser (A) consists of two rectifier bridges in anti-parallel mounting, but this choice is in no way limiting.
Le procédé et les précédents dispositifs ont été décrits pour une utilisation de courant monophasé, mais le procédé et les dispositifs relatifs à l'utilisation de courants polyphasés entrent dans le cadre de l'invention.The method and the preceding devices have been described for the use of single-phase current, but the method and the devices relating to the use of polyphase currents fall within the scope of the invention.
Il est bien entendu, enfin, que la présente invention n'a été décrite et représentée qu'à titre d'exemple préférentiel et que l'on pourra apporter des équivalences dans ses éléments constitutifs sans, pour autant, sortir du cadre de l'invention.It is clearly understood, finally, that the present invention has only been described and shown as a preferred example and that it is possible to provide equivalences in its constituent elements without, however, departing from the scope of the invention.
Claims (5)
the informations derived from these means as well as the characteristics of the product (H) being taken into account by said control system.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8204181A FR2523395A1 (en) | 1982-03-12 | 1982-03-12 | METHOD AND DEVICE FOR ADJUSTING THE AVERAGE INDUCED HEATING POWER IN A CONDUCTIVE FLAT CONTAINING ELECTROMAGNETICALLY IN CONTACTLESS POSITION |
| FR8204181 | 1982-03-12 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0090676A1 EP0090676A1 (en) | 1983-10-05 |
| EP0090676B1 true EP0090676B1 (en) | 1987-04-22 |
Family
ID=9271917
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP83400258A Expired EP0090676B1 (en) | 1982-03-12 | 1983-02-07 | Method and devices for regulating the mean induced heating power in a flat conductive product maintained in position electromagnetically without contact |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4531037A (en) |
| EP (1) | EP0090676B1 (en) |
| JP (1) | JPS58169789A (en) |
| DE (1) | DE3371157D1 (en) |
| FR (1) | FR2523395A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5483042A (en) * | 1990-06-04 | 1996-01-09 | Nordson Corporation | Magnetic separator |
| US5529703A (en) * | 1990-06-04 | 1996-06-25 | Nordson Corporation | Induction dryer and magnetic separator |
| US5847370A (en) * | 1990-06-04 | 1998-12-08 | Nordson Corporation | Can coating and curing system having focused induction heater using thin lamination cores |
| ZA9210102B (en) * | 1992-02-10 | 1993-08-24 | Heron Tech Inc | Induction dryer and magnetic separator |
| WO1993023970A1 (en) * | 1992-05-08 | 1993-11-25 | Heron Technologies, Inc. | Induction dryer and magnetic separator |
| JPH08222619A (en) * | 1995-02-14 | 1996-08-30 | Toshiba Corp | Manufacture of semiconductor |
| CA2789978C (en) | 2010-02-19 | 2015-11-24 | Nippon Steel Corporation | Transverse flux induction heating device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0087345A1 (en) * | 1982-02-18 | 1983-08-31 | Alsthom | Process and devices for minimizing the induced power in a flat conducting product suspended electromagnetically without contact |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE903847C (en) * | 1943-01-12 | 1954-02-11 | Deutsche Edelstahlwerke Ag | Device for one-sided electro-inductive heating of workpieces |
| NL243545A (en) * | 1958-09-19 | 1900-01-01 | ||
| FR1389902A (en) * | 1964-03-27 | 1965-02-19 | Method and device for the transport of strips, sections, tubes and the like made of a material conducting electric current, preferably through a passage furnace | |
| US3398252A (en) * | 1965-11-15 | 1968-08-20 | Westinghouse Electric Corp | Heat treatment apparatus |
| FR1576364A (en) * | 1967-12-12 | 1969-08-01 | ||
| GB1453489A (en) * | 1974-03-07 | 1976-10-20 | Electricity Council | Processing of billets slabs strips and other metal workpieces |
| US4321444A (en) * | 1975-03-04 | 1982-03-23 | Davies Evan J | Induction heating apparatus |
| GB1546367A (en) * | 1975-03-10 | 1979-05-23 | Electricity Council | Induction heating of strip and other elongate metal workpieces |
| DE2556057C2 (en) * | 1975-12-12 | 1982-04-01 | Sundwiger Eisenhütte Maschinenfabrik Grah & Co, 5870 Hemer | Method and device for heating metal strips, in particular non-ferrous metal strips |
| DE2622825A1 (en) * | 1976-05-21 | 1977-12-01 | Siemens Ag | Continuous induction heating of wire - where electronic circuit provides accurate heating despite variations in inlet temp. of wire |
| US4122321A (en) * | 1977-02-16 | 1978-10-24 | Park-Ohio Industries, Inc. | Induction heating furnace |
| US4296298A (en) * | 1978-06-12 | 1981-10-20 | Raytheon Company | Dielectric cooking apparatus |
-
1982
- 1982-03-12 FR FR8204181A patent/FR2523395A1/en active Granted
-
1983
- 1983-02-07 DE DE8383400258T patent/DE3371157D1/en not_active Expired
- 1983-02-07 EP EP83400258A patent/EP0090676B1/en not_active Expired
- 1983-02-08 US US06/464,948 patent/US4531037A/en not_active Expired - Lifetime
- 1983-03-10 JP JP58038404A patent/JPS58169789A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0087345A1 (en) * | 1982-02-18 | 1983-08-31 | Alsthom | Process and devices for minimizing the induced power in a flat conducting product suspended electromagnetically without contact |
Also Published As
| Publication number | Publication date |
|---|---|
| US4531037A (en) | 1985-07-23 |
| DE3371157D1 (en) | 1987-05-27 |
| FR2523395B1 (en) | 1984-06-01 |
| FR2523395A1 (en) | 1983-09-16 |
| JPH0221116B2 (en) | 1990-05-11 |
| EP0090676A1 (en) | 1983-10-05 |
| JPS58169789A (en) | 1983-10-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0090676B1 (en) | Method and devices for regulating the mean induced heating power in a flat conductive product maintained in position electromagnetically without contact | |
| FR2893200A1 (en) | ALTERNATOR. | |
| FR2510319A1 (en) | ALTERNATOR, PARTICULARLY FOR AUTOMOBILES | |
| EP1981160A1 (en) | Method and system for managing the temperature in a speed controller | |
| FR2679079A1 (en) | VOLTAGE CONVERSION DEVICE FOR CONTINUOUS VOLTAGE CONSUMER CIRCUIT. | |
| FR2893786A1 (en) | CONTROL METHOD AND APPARATUS FOR LIMITING THE CURRENT OF A CONTROL SYSTEM OF AN INDUCTION MACHINE | |
| EP0783201B1 (en) | Synchronous type electric motor and vehicle equipped with such a motor | |
| FR2933550A1 (en) | METHOD FOR DETERMINING THE INDUCTIONS OF A SYNCHRONOUS MACHINE WITH PERMANENT MAGNETS | |
| EP0070232A1 (en) | Method and arrangement for the homogeneous heating with transverse flux electromagnetic induction of flat, conductive and amagnetic products | |
| FR2693071A1 (en) | Homogeneous inductive heating device for flat metallic products on parade. | |
| FR2486328A1 (en) | IMPROVED ENERGY SAVING DEVICE FOR INDUCTION MOTORS | |
| EP0623991B1 (en) | Dimming device for a load | |
| FR2586146A1 (en) | HIGH POWER ELECTRONIC VOLTAGE CONVERTER | |
| EP4324070A1 (en) | Method and device for recovering electrical energy on a single-phase or multiphase power cable | |
| WO2003050933A2 (en) | Alternator, in particular for motor vehicle | |
| EP0080925A1 (en) | Static converter with a twelve-phase circuit of two Graetz bridges for the suppression of the 5th and 7th harmonics in the network | |
| EP0087345B1 (en) | Process and devices for minimizing the induced power in a flat conducting product suspended electromagnetically without contact | |
| EP0926807A1 (en) | Three-phase AC/DC converter | |
| EP1070384B1 (en) | Method and device for controlling a static converter powering an electrical source | |
| FR2511806A1 (en) | PROCESS FOR THE SUPPLY AND DEMAGNETIZATION OF HIGH-POWER DIRECT CURRENT MAGNETS | |
| EP2100363A2 (en) | Generator and method for generating a direct current high voltage, and dust collector using such generator | |
| FR2881296A1 (en) | Speed controller`s output current limiting method for asynchronous electric motor, involves multiplying corrected stator frequency with constant based on control law to obtain control voltage applied to motor | |
| FR2607043A1 (en) | ELECTROMAGNETIC DRIVE OF A FRICTION WELDING MACHINE | |
| FR2566957A1 (en) | METHOD FOR INSTALLING AIR CORE INDUCTION COILS | |
| EP0457649A1 (en) | Measuring circuit for instantaneous power |
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 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): BE CH DE GB IT LI LU Designated state(s): BE CH DE GB IT LI LU |
|
| 17P | Request for examination filed |
Effective date: 19840405 |
|
| RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: ALSTHOM |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE CH DE GB IT LI LU |
|
| REF | Corresponds to: |
Ref document number: 3371157 Country of ref document: DE Date of ref document: 19870527 |
|
| ITF | It: translation for a ep patent filed | ||
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| 26N | No opposition filed | ||
| ITTA | It: last paid annual fee | ||
| EPTA | Lu: last paid annual fee | ||
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19970113 Year of fee payment: 15 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19970116 Year of fee payment: 15 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19970124 Year of fee payment: 15 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19970131 Year of fee payment: 15 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: LU Payment date: 19970206 Year of fee payment: 15 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980207 Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980207 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980228 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980228 Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980228 |
|
| BERE | Be: lapsed |
Owner name: ALSTHOM Effective date: 19980228 |
|
| GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19980207 |
|
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19981103 |