EP0637897B1 - Vorrichtung zum induktiven Längsfelderwärmen von flachem Metallgut - Google Patents

Vorrichtung zum induktiven Längsfelderwärmen von flachem Metallgut Download PDF

Info

Publication number: EP0637897B1
Authority: EP; European Patent Office
Prior art keywords: inductors; inductor; conductor loops; another; active sections
Prior art date: 1993-08-02
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.): Expired - Lifetime

Application number

EP94111752A

Other languages

German (de)

English (en)

French (fr)

Other versions

EP0637897A3 (de

EP0637897A2 (de

Inventor

Dieter Dipl.-Ing. Schluckebier

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.)

Otto Junker GmbH

Original Assignee

Otto Junker 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.)

1993-08-02

Filing date

1994-07-28

Publication date

2000-01-19

1994-07-28 Application filed by Otto Junker GmbH filed Critical Otto Junker GmbH

1995-02-08 Publication of EP0637897A2 publication Critical patent/EP0637897A2/de

1995-09-20 Publication of EP0637897A3 publication Critical patent/EP0637897A3/de

2000-01-19 Application granted granted Critical

2000-01-19 Publication of EP0637897B1 publication Critical patent/EP0637897B1/de

2014-07-28 Anticipated expiration legal-status Critical

Status Expired - Lifetime legal-status Critical Current

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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
- H05B6/36—Coil arrangements

Definitions

the invention relates to a device for inductive Longitudinal field heating of flat metal goods, e.g. Tapes, Plates or the like made of non-ferrous metal, steel or a ferromagnetic material, with at least two with Alternating current, in particular medium-frequency alternating current, fed inductors, each provided with conductor loops are, the effective sections of which are each magnetic Generate alternating field.
flat metal goods e.g. Tapes, Plates or the like made of non-ferrous metal, steel or a ferromagnetic material
Alternating current in particular medium-frequency alternating current, fed inductors, each provided with conductor loops are, the effective sections of which are each magnetic Generate alternating field.
the main advantage of the known device is the high Uniform heating over the entire width of the metal, being even at different widths achieve an even temperature distribution of the metal material leaves.
this device also has some disadvantages on. Firstly, there is no satisfactory level of efficiency can be achieved in the heating when using metal material different widths and thicknesses should be heated. When changing to metal goods of different widths and / or thicknesses replacement inductors are required in the known device, to even with different dimensions of the To achieve good electrical efficiency. But this is a very cumbersome and uneconomical Procedure, as the entire plant is shut down must be and for example, for the continuous Operation usually attached metal strips separately and after installing the replacement inductor need to be reconnected. This creates considerable Production downtimes. Furthermore occur in the known Device on the induction coil on stray fields that the electrical efficiency of this heater further belittle.
DE 39 28 629 A1 is a device known for inductive heating of flat metallic goods, which has at least two inductors, which are in pairs on opposite sides of the metal goods opposite. This device allows through separate Switching individual conductor loops an adjustment to different widths of the metallic goods. With this device, however, cross-field heating carried out, a lower compared to the longitudinal field heating Uniformity of heating across the entire width of the metal causes.
the present invention has for its object a To design the device of the type mentioned in the introduction that it is adaptable to the respective metal goods width and easily accessible from outside for cleaning and maintenance work is to largely avoid production downtimes. It should also be achieved that the device can be produced inexpensively due to their design.
the effective sections of the conductor loops can a straight line or one that deviates from a straight line Have course.
the device according to the invention can also be designed in this way be that the effective sections of the conductor loops in Grooves of the inductor cores are arranged. This will become allows an even more compact design of the inductor, on the other hand the coupling of the magnetic lines of force improved on the iron core.
the device according to the invention can also be designed in this way be that the inductors and the flat metal goods are relative are movable to each other.
the inductors can be relative be moved to plates or the like. It is alike possible to arrange the inductors statically and the flat metal in the form of a ribbon or the like to move.
the device according to the invention can also be designed in this way be that the effective sections of the conductor loops of the Inductors in the longitudinal, transverse or inclined direction of movement to get lost.
the device according to the invention can also be designed in this way be that several inductor pairs arranged side by side are, their inductor cores jammed together or are integrally formed with each other.
the Area of influence of an inductor unit to the respective requirements be adjusted.
the current direction in the effective sections of the conductor loops adjacent Inductors can be the same or opposite.
By such a way of arranging several placed side by side Inductors can increase electrical efficiency become.
With different electrical polarity neighboring Inductors are formed according to the number of the inductors have several areas in the metal material in which closed eddy currents flow. This leads to one single closed eddy current path to an elevated electrical power density in the metal goods.
using multiple inductors side by side is also a good coordination on the respective metal width possible.
the device according to the invention can be designed that inductor pairs are clocked and offset in time from each other are switchable.
inductor pairs are used Use, one of which is only a small number of conductor loops and is in a marginal or intermediate position to others Inductors located. This way the education counteracted by unwanted temperature shadows in the metal goods become.
the device according to the invention can also be designed in this way be that several inductor cores one behind the other in the direction of movement are arranged.
the effective sections the conductor loops of each other in the direction of movement following inductors the same or different Have inclinations to the transport direction to in this way to further help to even out the warming.
the device according to the invention can also be designed in this way be that the intermediate areas of two adjacent inductors Trim cores are assigned. This way, a Compensation for any temperature shadows in the area between Causes inductors.
the device according to the invention is designed that the effective sections of the conductor loops of a Inductor are connected in parallel to each other. On this way the number of returns can be reduced and so that the construction work can be reduced.
the device according to the invention can also be designed in this way be that the effective sections of the conductor loops a Inductor pair lie in a common circuit.
the device according to the invention can also be designed that the conductor loops for feedback on the side respective inductor core are guided.
the device according to the invention can also be designed in this way be that the conductor loops effective sections in two form adjacent inductors.
the device according to the invention can be designed in this way be that conductor loops of at least one inductor are separately switchable.
the device can be connected to the Width of the goods to be heated can be adjusted without it to require any conversions.
the inductors 1,2 are equally designed and have one another an iron core 4.5 each.
a receptacle 6 is provided on each side of the iron cores 4, 5, in which the effective sections 7 from here on conductor loops shown running parallel to each other are arranged. All effective sections 7 of the Conductor loops of the upper inductor 1 are the same Direction through which current flows. This also applies to all effective ones Sections 7 of the lower inductor 2 except that the current direction is reversed here.
the effective sections 7, the conductor loops can in the recordings 6 be embedded in suitable material or run in grooves not shown here.
Fig. 1 can be seen as a juxtaposition of two pairs of inductors 3 can be understood.
the iron cores 4,5 are included in one piece for the inductors 1,1 'and 2,2'.
Fig. 1 are all effective sections 7 of the conductor loops arranged in grooves 9 of the iron cores 4, 5, the current direction in the effective sections 7 of the inductors 1, 2 ' is equal to. Also have the same current direction with each other the effective sections 7 in the inductors 2.1 'with the Exception that the current is in the opposite direction flows as in the inductors 1, 2 '.
the embodiment of the device according to FIG. 1 can Area of transition between the inductors 1, 1 'or 2,2 'a trimming core 10 may be connected in order here, if necessary to compensate for temperature shadows. This is illustrated in Fig. 2, in which the arrow 11 as well 1 shows the direction of movement of the metal goods 3.
Fig. 4 is to be understood as a supplement to Fig. 1 by not only the effective sections 7 of the conductor loops, but also identifies their return. This happens provided on the sides of the iron cores 4,5 in there Recesses 19.
FIG. 5 shows an upper inductor 1 with an iron core 4 and a lower inductor 2 with an iron core 5. Grooves 9 are provided in the iron cores 4, 5, in which there are effective sections 7 of conductor loops are located. All effective sections are 7 of the upper inductor 1 parallel to each other in a circuit switched in which all effective sections 7th parallel to each other, but with opposite polarity are switched.
Fig. 6 shows schematically two in the direction of movement (Arrow 11) of the metal goods 3 arranged one behind the other Inductors 1, in which the effective sections of the Conductor loops are offset from each other by 90 °.
All inductors are connected to a medium frequency AC source connected.

Landscapes

Physics & Mathematics (AREA)
Electromagnetism (AREA)
Engineering & Computer Science (AREA)
Power Engineering (AREA)
General Induction Heating (AREA)
Furnace Details (AREA)

EP94111752A 1993-08-02 1994-07-28 Vorrichtung zum induktiven Längsfelderwärmen von flachem Metallgut Expired - Lifetime EP0637897B1 (de)

Applications Claiming Priority (2)

Application Number	Priority Date	Filing Date	Title
DE4325868		1993-08-02
DE4325868A DE4325868C2 (de)	1993-08-02	1993-08-02	Vorrichtung zum induktiven Längsfelderwärmen von flachem Metallgut

Publications (3)

Publication Number	Publication Date
EP0637897A2 EP0637897A2 (de)	1995-02-08
EP0637897A3 EP0637897A3 (de)	1995-09-20
EP0637897B1 true EP0637897B1 (de)	2000-01-19

Family

ID=6494253

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
EP94111752A Expired - Lifetime EP0637897B1 (de)	1993-08-02	1994-07-28	Vorrichtung zum induktiven Längsfelderwärmen von flachem Metallgut

Country Status (6)

Country	Link
EP (1)	EP0637897B1 (da)
JP (1)	JPH07153560A (da)
AT (1)	ATE189097T1 (da)
DE (2)	DE4325868C2 (da)
DK (1)	DK0637897T3 (da)
ES (1)	ES2144020T3 (da)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US5844213A (en) *	1990-01-31	1998-12-01	Inductotherm Corp.	Induction heating coil assembly for prevention of circulating currents in induction heating lines for continuous-cast products
DE19827577C1 (de) *	1998-06-20	1999-10-28	Abg Allg Baumaschinen Gmbh	Einbaubohle für einen Straßenfertiger
KR100998962B1 (ko) *	2003-07-21	2010-12-09	매그나칩 반도체 유한회사	코어부를 삽입한 인덕터 제조방법
JP2008226780A (ja) *	2007-03-15	2008-09-25	Mitsui Eng & Shipbuild Co Ltd	誘導加熱装置
JP6665928B2 (ja)	2016-03-30	2020-03-13	日本製鉄株式会社	誘導加熱装置および誘導加熱方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US3725629A (en) *	1971-07-16	1973-04-03	Park O Ind Inc	Slab heating device

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
BE501964A (da) *
US2448011A (en) *	1944-09-09	1948-08-31	Westinghouse Electric Corp	Method and apparatus for induction heating of metal strips
US2902572A (en) *	1957-03-05	1959-09-01	Penn Induction Company	Induction heating of metal strip
US3731040A (en) *	1971-09-24	1973-05-01	Park Ohio Industries Inc	Billet heating coil
CA1320900C (en) *	1986-08-06	1993-08-03	Jerome B. Zeldis	Assay to detect the presence of live virus in vitro
US4761530A (en) *	1987-04-03	1988-08-02	National Steel Corporation	Electric induction heat treating furnace
DE3928629A1 (de) *	1989-08-30	1991-03-14	Junker Gmbh O	Vorrichtung zum induktiven erwaermen von flachem metallischem gut
GB2262420B (en) *	1991-12-03	1995-02-08	Electricity Ass Tech	Induction heating apparatus

1993
- 1993-08-02 DE DE4325868A patent/DE4325868C2/de not_active Expired - Fee Related
1994
- 1994-07-28 EP EP94111752A patent/EP0637897B1/de not_active Expired - Lifetime
- 1994-07-28 DE DE59409084T patent/DE59409084D1/de not_active Expired - Fee Related
- 1994-07-28 DK DK94111752T patent/DK0637897T3/da active
- 1994-07-28 ES ES94111752T patent/ES2144020T3/es not_active Expired - Lifetime
- 1994-07-28 AT AT94111752T patent/ATE189097T1/de not_active IP Right Cessation
- 1994-08-01 JP JP6180270A patent/JPH07153560A/ja not_active Withdrawn

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US3725629A (en) *	1971-07-16	1973-04-03	Park O Ind Inc	Slab heating device

Also Published As

Publication number	Publication date
ATE189097T1 (de)	2000-02-15
DE59409084D1 (de)	2000-02-24
JPH07153560A (ja)	1995-06-16
ES2144020T3 (es)	2000-06-01
DK0637897T3 (da)	2000-07-10
EP0637897A3 (de)	1995-09-20
DE4325868C2 (de)	1997-11-13
DE4325868C1 (de)	1995-01-12
EP0637897A2 (de)	1995-02-08

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Publication	Publication Date	Title
DE3635961C2 (da)	1992-03-26
DE3751460T2 (de)	1996-01-25	Induktionsheizvorrichtung.
DE2609978C2 (da)	1987-06-11
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DE3928629C2 (da)	1992-01-09
DE69112208T2 (de)	1996-05-02	Verfahren und vorrichtung zum induktiven erwärmen eines sich bewegenden länglichen gegenstandes.
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EP0637897B1 (de)	2000-01-19	Vorrichtung zum induktiven Längsfelderwärmen von flachem Metallgut
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EP4399974A1 (de)	2024-07-17	Waffelbackanlage
WO2021115508A1 (de)	2021-06-17	Querfeldinduktionsheizeinrichtung
DE2827045C3 (de)	1982-02-11	Vorrichtung zum Druckumformen von Metallen mittels eines impulsförmigen Magnetfeldes
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