EP0101922B1 - Method and device for treating ferromagnetic materials - Google Patents

Method and device for treating ferromagnetic materials Download PDF

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Publication number
EP0101922B1
EP0101922B1 EP83107298A EP83107298A EP0101922B1 EP 0101922 B1 EP0101922 B1 EP 0101922B1 EP 83107298 A EP83107298 A EP 83107298A EP 83107298 A EP83107298 A EP 83107298A EP 0101922 B1 EP0101922 B1 EP 0101922B1
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EP
European Patent Office
Prior art keywords
pulses
treatment
control block
ferromagnetic materials
polarity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83107298A
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German (de)
French (fr)
Other versions
EP0101922A1 (en
Inventor
Boris Georgiev Dipl.-Ing. Makedonski
Janaki Rostislavov Dipl.-Ing. Blaskov
Ljubomir Pavlov Dipl.-Ing. Alipiev
Haralampi Angelov Dipl.-Ing. Atanassov
Nedeltscho Christov Dipl.-Ing. Todorov
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.)
ZENTRALEN MASCHINOSTROITELEN INSTITUT
Original Assignee
ZENTRALEN MASCHINOSTROITELEN INSTITUT
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.)
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Application filed by ZENTRALEN MASCHINOSTROITELEN INSTITUT filed Critical ZENTRALEN MASCHINOSTROITELEN INSTITUT
Priority to AT83107298T priority Critical patent/ATE17535T1/en
Publication of EP0101922A1 publication Critical patent/EP0101922A1/en
Application granted granted Critical
Publication of EP0101922B1 publication Critical patent/EP0101922B1/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F13/00—Apparatus or processes for magnetising or demagnetising

Definitions

  • the invention relates to a method and a device for treating ferromagnetic materials for use in mechanical engineering.
  • a method for treating ferromagnetic materials by means of a pulse magnetic field with single-pole magnetic pulses with a specific pulse repetition frequency, amplitude and length is known.
  • the ferromagnetic material to be treated is introduced into the magnetic field of the inductor, after which it is subjected to complete demagnetization.
  • a device for performing the method which consists of a series connection of a power source, a generator for single-pole electrical pulses, which can be regulated according to amplitude and frequency, and a power block with an inductor, in the magnetic field of which the ferromagnetic material to be treated is introduced; there is also a control block connected to the power source.
  • a disadvantage of the method and the device is the low wear resistance of the ferromagnetic materials.
  • the object on which the invention is based is to specify a method and a device for treating ferromagnetic materials with increased wear resistance.
  • the object of the invention is achieved by a method in which the ferromagnetic material is treated in a bipolar magnetic field with a certain length and repetition frequency of the pulses and the ratio between the amplitudes of the positive and negative pulses of 1.8 to 0.2.
  • the pulses of one polarity have a uniform or lower frequency compared to the repetition frequency of the pulses of the other polarity.
  • the bipolar magnetic pulses gradually decrease.
  • the device contains a power supply source which is connected to a control block and a generator.
  • a stabilized, adjustable rectifier is connected to the power supply source and the control block.
  • the power block with an inductor consists of two parts, each of which consists of a series connection of capacitor and coil and a thyristor connected in parallel.
  • the anodes of the thyristors are connected to the stabilized, adjustable rectifier, their control electrodes are connected to the generator.
  • the control block is connected to a trigger.
  • the drawing shows the block diagram of an embodiment of the device according to the invention.
  • the device consists of a power supply source 1, which is connected to a stabilized, adjustable rectifier 2, a generator 3 and a control block 4.
  • the control block 4 is connected to the stabilized, adjustable rectifier 2 and the generator 3.
  • the supply voltage is simultaneously supplied to the current supply source 1 and the stabilized, adjustable rectifier 2.
  • the power block with inductor 5 consists of two parts, each of which consists of a series connection of capacitor 6 and coil 7 and a thyristor 8 connected in parallel.
  • the anodes of the two thyristors 8 are each connected to an output of the stabilized, adjustable rectifier 2. Your cathodes are grounded.
  • the control electrodes of the thyristors 8 are connected to the two outputs of the generator 3.
  • the ferromagnetic material 9 to be treated is introduced into the field generated by the coils 7;
  • a trigger 10 is arranged in front of the coils 7 and is connected to the control block 4.
  • the coils 7 can also have a magnetic conductor, not shown.
  • the operation of the device is as follows: depending on the type of ferromagnetic material to be treated, a certain program is entered in the control block 4. With the introduction of the ferromagnetic material 9 to be treated into the field generated by the coils 7, the trigger 10 actuates the control block 4, which supplies the stabilized, adjustable rectifier 2 and the generator 3 with control pulses. Control pulses are supplied from generator 3 to the two parts of the power block with inductor 5. Both thyristors 8 open one after the other, the field of coils 7 being bipolar. Each polarity is determined by which one of the coils 7 has been actuated by the corresponding thyristor 8. The amplitude is changed by the voltage supplied by the stabilized, controllable current rectifier 2. After the time entered in advance by the program has elapsed, signals are generated and fed from the control block 4 to the stabilized, adjustable rectifier 2, which gradually begins to reduce the supply voltage of the two thyristors 8 to zero.

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  • Power Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Vending Machines For Individual Products (AREA)
  • Feedback Control In General (AREA)
  • Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
  • Liquid Crystal Substances (AREA)
  • Manufacturing Cores, Coils, And Magnets (AREA)
  • Soft Magnetic Materials (AREA)
  • Treatments Of Macromolecular Shaped Articles (AREA)
  • Hard Magnetic Materials (AREA)
  • Generation Of Surge Voltage And Current (AREA)
  • Magnetic Treatment Devices (AREA)
  • Chemical Vapour Deposition (AREA)

Abstract

1. Method for the treatment of ferromagnetic materials in which the materials (9) are exposed to a pulse magnetic field with certain pulse recurrence frequency, amplitude and length and are demagnetized at the end of the treatment, characterized in that the pulse field is bipolar with a ration of positive and negative amplitudes of 1.8 to 0.2, with the pulses of the one polarity having the same or lower recurrence frequency than the pulses of the other polarity.

Description

Die Erfindung betrifft ein Verfahren und eine Vorrichtung zur Behandlung von ferromagnetischen Werkstoffen zur Anwendung im Maschinenbau.The invention relates to a method and a device for treating ferromagnetic materials for use in mechanical engineering.

Es ist ein Verfahren zur Behandlung von ferromagnetischen Werkstoffen mittels eines Impulsmagnetfeldes mit einpoligen Magnetimpulsen mit bestimmter Impulsfolgefrequenz, Amplitude und Länge bekannt. Der zu behandelnde ferromagnetische Werkstoff wird in das Magnetfeld des Induktors eingeführt, worauf er einer vollständigen Entmagnetisierung unterzogen wird.A method for treating ferromagnetic materials by means of a pulse magnetic field with single-pole magnetic pulses with a specific pulse repetition frequency, amplitude and length is known. The ferromagnetic material to be treated is introduced into the magnetic field of the inductor, after which it is subjected to complete demagnetization.

Es ist weiter eine Vorrichtung zur Durchführung des Verfahrens bekannt, die aus einer Reihenschaltung aus einer Stromspeisequelle, einem Generator für einpolige elektrische Impulse, die nach Amplitude und Frequenz regelbar sind, sowie aus einem Kraftblock mit Induktor besteht, in dessen Magnetfeld der zu behandelnde ferromagnetische Werkstoff eingeführt wird; es ist auch ein Steuerblock vorhanden, der an die Stromspeisequelle angeschlossen ist.It is also known a device for performing the method, which consists of a series connection of a power source, a generator for single-pole electrical pulses, which can be regulated according to amplitude and frequency, and a power block with an inductor, in the magnetic field of which the ferromagnetic material to be treated is introduced; there is also a control block connected to the power source.

. Ein Nachteil des Verfahrens und der Vorrichtung ist die niedrige Verschleißfestigkeit der ferromagnetischen Werkstoffe.. A disadvantage of the method and the device is the low wear resistance of the ferromagnetic materials.

Die der Erfindung zugrundeliegende Aufgabe besteht darin, ein Verfahren und eine Vorrichtung zur Behandlung von ferromagnetischen Werkstoffen mit erhöhter Verschleißfestigkeit anzugeben.The object on which the invention is based is to specify a method and a device for treating ferromagnetic materials with increased wear resistance.

Die Aufgabe der Erfindung wird durch ein Verfahren gelöst, bei dem der ferromagnetische Werkstoff in einem bipoligen Magnetfeld mit bestimmter Länge und Folgefrequenz der Impulse und Verhältnis zwischen den Amplituden der positiven und negativen Impulse von 1,8 bis 0,2 behandelt wird. Die Impulse von der einen Polarität haben eine gleichmäßige oder niedrigere Frequenz im Vergleich mit der Folgefrequenz der Impulse der anderen Polarität. Zum Schluß der Behandlung lassen die bipolaren Magnetimpulse allmählich nach.The object of the invention is achieved by a method in which the ferromagnetic material is treated in a bipolar magnetic field with a certain length and repetition frequency of the pulses and the ratio between the amplitudes of the positive and negative pulses of 1.8 to 0.2. The pulses of one polarity have a uniform or lower frequency compared to the repetition frequency of the pulses of the other polarity. At the end of the treatment, the bipolar magnetic pulses gradually decrease.

Die erfindungsgemäße Vorrichtung enthält eine Stromspeisequelle, die an einen Steuerblock und einen Generator angeschlossen ist. Ein stabilisierter regelbarer Gleichrichter ist an die Stromspeisequelle und den Steuerblock angeschlossen. Der Kraftblock mit einem Induktor besteht aus zwei Teilen, von denen jeder aus einer Reihenschaltung aus Kondensator und Spule und einem dazu parallelgeschalteten Thyristor besteht. Die Anoden der Thyristoren sind mit dem stabilisierten regelbaren Gleichrichter, ihre Steuerelektroden sind mit dem Generator verbunden. Der Steuerblock ist an einen Trigger angeschlossen.The device according to the invention contains a power supply source which is connected to a control block and a generator. A stabilized, adjustable rectifier is connected to the power supply source and the control block. The power block with an inductor consists of two parts, each of which consists of a series connection of capacitor and coil and a thyristor connected in parallel. The anodes of the thyristors are connected to the stabilized, adjustable rectifier, their control electrodes are connected to the generator. The control block is connected to a trigger.

Bei Anwendung des erfindungsgemäßen Verfahrens und der erfindungsgemäßen Vorrichtung wird die Verschleißfestigkeit der behandelten Werkstoffe erhöht. Die Zeichnung zeigt das Blockschaltbild eines Ausführungsbeispiels der erfindungsgemäßen Vorrichtung.When using the method and the device according to the invention, the wear resistance of the treated materials is increased. The drawing shows the block diagram of an embodiment of the device according to the invention.

Die Vorrichtung besteht aus einer Stromspeisequelle 1, die an einen stabilisierten regelbaren Gleichrichter 2, einen Generator 3 und einen Steuerblock 4 angeschlossen ist. Der Steuerblock 4 ist mit dem stabilisierten regelbaren Gleichrichter 2 und dem Generator 3 verbunden. Die Speisespannung wird gleichzeitig der Stromspeisequelle 1 und dem stabilisierten regelbaren Gleichrichter 2 zugeführt. Der Kraftblock mit Induktor 5 besteht aus zwei Teilen, von denen jeder aus einer Reihenschaltung aus Kondensator 6 und Spule 7 und einem dazu parallelgeschalteten Thyristor 8 besteht. Die Anoden der beiden Thyristoren 8 sind je mit einem Ausgang des stabilisierten regelbaren Gleichrichters 2 verbunden. Ihre Kathoden sind geerdet. Die Steuerelektroden der Thyristoren 8 sind mit den beiden Ausgängen des Generators 3 verbunden. Der zu behandelnde ferromagnetische Werkstoff 9 wird in das von den Spulen 7 erzeugte Feld eingeführt; vor den Spulen 7 ist ein Trigger 10 angeordnet, der an den Steuerblock 4 angeschlossen ist. Die Spulen 7 können auch einen nicht gezeigten Magnetleiter aufweisen.The device consists of a power supply source 1, which is connected to a stabilized, adjustable rectifier 2, a generator 3 and a control block 4. The control block 4 is connected to the stabilized, adjustable rectifier 2 and the generator 3. The supply voltage is simultaneously supplied to the current supply source 1 and the stabilized, adjustable rectifier 2. The power block with inductor 5 consists of two parts, each of which consists of a series connection of capacitor 6 and coil 7 and a thyristor 8 connected in parallel. The anodes of the two thyristors 8 are each connected to an output of the stabilized, adjustable rectifier 2. Your cathodes are grounded. The control electrodes of the thyristors 8 are connected to the two outputs of the generator 3. The ferromagnetic material 9 to be treated is introduced into the field generated by the coils 7; A trigger 10 is arranged in front of the coils 7 and is connected to the control block 4. The coils 7 can also have a magnetic conductor, not shown.

Die Wirkungsweise der Vorrichtung ist wie folgt: in Abhängigkeit von der Art des zu behandelnden ferromagnetischen Werkstoffes wird ein bestimmtes Programm in den Steuerblock 4 eingegeben. Mit der Einführung des zu behandelnden ferromagnetischen Werkstoffs 9 in das von den Spulen 7 erzeugte Feld betätigt der Trigger 10 den Steuerblock 4, der dem stabilisierten regelbaren Gleichrichter 2 und dem Generator 3 Steuerimpulse zuführt. Vom Generator 3 werden Steuerimpulse den beiden Teilen des Kraftblocks mit Induktor 5 zugeführt. Beide Thyristoren 8 öffnen nacheinander, wobei das Feld der Spulen 7 bipolar ist. Jede Polarität wird dadurch bestimmt, welche von den Spulen 7 durch den ihr entsprechenden Thyristor 8 betätigt worden ist. Die Amplitude wird durch die vom stabilisierten regelbaren Stromgleichrichter 2 zugeführte Spannung verändert. Nach dem Ablauf der im voraus durch das Programm eingegebenen Zeit werden Signale erzeugt, und vom Steuerblock 4 dem stabilisierten regelbaren Gleichrichter 2 zugeführt, der die Speisespannung der beiden Thyristoren 8 allmählich auf Null zu vermindern beginnt.The operation of the device is as follows: depending on the type of ferromagnetic material to be treated, a certain program is entered in the control block 4. With the introduction of the ferromagnetic material 9 to be treated into the field generated by the coils 7, the trigger 10 actuates the control block 4, which supplies the stabilized, adjustable rectifier 2 and the generator 3 with control pulses. Control pulses are supplied from generator 3 to the two parts of the power block with inductor 5. Both thyristors 8 open one after the other, the field of coils 7 being bipolar. Each polarity is determined by which one of the coils 7 has been actuated by the corresponding thyristor 8. The amplitude is changed by the voltage supplied by the stabilized, controllable current rectifier 2. After the time entered in advance by the program has elapsed, signals are generated and fed from the control block 4 to the stabilized, adjustable rectifier 2, which gradually begins to reduce the supply voltage of the two thyristors 8 to zero.

Claims (2)

1. Method for the treatment of ferromagnetic materials in which the materials (9) are exposed to a pulse magnetic field with certain pulse recurrence frequency, amplitude and length and are demagnetized at the end of the treatment, characterised in that the pulse field is bipolar with a ratio of positive and negative amplitudes of 1.8 to 0.2, with the pulses of the one polarity having the same or lower recurrence frequency than the pulses of the other polarity.
2. Apparatus for the treatment of ferromagnetic materials by carrying out the process according to the preamble of claim 1, with a current supply source (1) which is connected to a control block (4) and a generator (3) which is connected to a power block (5) with inducer characterised by a stabilised adjustable rectifier (2) which is connected to the current supply source (1) and the control block (4), with the power block (5) with inducer consisting of two parts which consist of a series circuit arrangement of condenser (6) and coil (7) and in addition a parallel connected thyristor (8), with the anodes of the thyristors (8) being connected with the stabilised adjustable rectifier (2), the control electrodes with the generator (3) and a trigger (10) being connected to the control block (4).
EP83107298A 1982-07-27 1983-07-25 Method and device for treating ferromagnetic materials Expired EP0101922B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83107298T ATE17535T1 (en) 1982-07-27 1983-07-25 METHOD AND DEVICE FOR THE TREATMENT OF FERROMAGNETIC MATERIALS.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
BG8257551A BG38909A1 (en) 1982-07-27 1982-07-27 Method and device for acting on ferromagnetic materials
BG57551/82 1982-07-27

Publications (2)

Publication Number Publication Date
EP0101922A1 EP0101922A1 (en) 1984-03-07
EP0101922B1 true EP0101922B1 (en) 1986-01-15

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EP83107298A Expired EP0101922B1 (en) 1982-07-27 1983-07-25 Method and device for treating ferromagnetic materials

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EP (1) EP0101922B1 (en)
JP (1) JPS5972115A (en)
AT (1) ATE17535T1 (en)
AU (2) AU1722983A (en)
BG (1) BG38909A1 (en)
CA (1) CA1223303A (en)
CS (1) CS256908B1 (en)
DE (1) DE3361854D1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BG41281A1 (en) * 1985-07-29 1987-05-15 Makedonski Device for magneto- impulse treatment of ferromagnetic materials
EP1513168B1 (en) * 2003-09-02 2017-03-08 Albert Maurer Method and apparatus for magnetising a magnet system
US7868721B2 (en) * 2008-04-04 2011-01-11 Cedar Ridge Research, Llc Field emission system and method

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD146726A1 (en) * 1979-10-22 1981-02-25 Siegfried Wirthgen METHOD FOR GENERATING DC CURRENT PULSES IN COILS OF ELECTROMAGNETS

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE790729A (en) * 1971-11-19 1973-02-15 Lenoir Raoul Ets COIL EXCITATION CURRENT CONTROL DEVICE PRODUCING A MAGNETIC FLOW OF REVERSE POLARITY
CH582411A5 (en) * 1975-03-03 1976-11-30 Bbc Brown Boveri & Cie
US4158873A (en) * 1977-08-31 1979-06-19 Magnaflux Corporation Demagnetizing methods and apparatus
IT1119003B (en) * 1979-06-25 1986-03-03 Riv Officine Di Villar Perosa DEMAGNETIZER DEVICE
IT1141165B (en) * 1980-02-06 1986-10-01 Sdm Sistemi & Dispositivi Magn SYSTEM AND CIRCUIT PROVISION FOR THE DEMAGNETIZATION OF PERMANENT MAGNETS

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD146726A1 (en) * 1979-10-22 1981-02-25 Siegfried Wirthgen METHOD FOR GENERATING DC CURRENT PULSES IN COILS OF ELECTROMAGNETS

Also Published As

Publication number Publication date
AU1377388A (en) 1988-07-07
DE3361854D1 (en) 1986-02-27
CA1223303A (en) 1987-06-23
AU1722983A (en) 1984-02-02
ATE17535T1 (en) 1986-02-15
BG38909A1 (en) 1986-03-14
EP0101922A1 (en) 1984-03-07
CS256908B1 (en) 1988-04-15
JPS5972115A (en) 1984-04-24

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