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US4384313A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for demagnetizing components by alternating magnetic fields of varying intensity

Assignee: Individual
•
Filing: 1981-02-12
•
Granted: 1983-05-17
•
Expires: 2001-02-12
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Abstract

Abstract A process for demagnetizing components by subjecting them to the influences of the alternating magnetic field of a coil supplied by an oscillator circuit which includes a capacitor also includes providing a voltage supply to the oscillator at the resonant frequency and thereafter reducing the intensity of the alternating field acting on the components. This can be done in several ways, such as by varying the frequency of the supply voltage or by varying the capacitance connected in circuit with the coil. The process may also be used for calibrating permanent magnets.

Inventors

  • 👤 Erich Steingroever
  • 👤 Dietrich Steingroever

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 19:03
CPC Classifications
H; H01; H01F; H01F13/00; H01F13/006

Claims Analysis

Total Claims: 27
Claim 1
Independent Claim 117 words
In a process for the demagnetization of components subjected to the influence of an alternating magnetic field of a coil connected with capacitor means in an oscillator circuit supplied by an alternating voltage means, comprising the steps of: (a) placing a component to be demagnetized in the vicinity of said coil to be subjected to an alternating magnetic field generated by said coil; (b) varying the phase between voltage and current of the oscillator circuit to produce a control voltage to bring the frequency of the supplied voltage from a non-resonant frequency to the resonant frequency of the oscillator circuit, and; (c) thereafter reducing the intensity of the alternating magnetic field to which said component is subjected.
Claim 2
Dependent Claim 117 words
In a process for the demagnetization of components subjected to the influence of an alternating magnetic field of a coil connected with capacitor means in an oscillator circuit supplied by an alternating voltage means, comprising the steps of: (a) placing a component to be demagnetized in the vicinity of said coil to be subjected to an alternating magnetic field generated by said coil; (b) varying the phase between voltage and current of the oscillator circuit to produce a control voltage to bring the frequency of the supplied voltage from a non-resonant frequency to the resonant frequency of the oscillator circuit, and; (c) thereafter reducing the intensity of the alternating magnetic field to which said component is subjected.
Claim 3
Dependent Claim 28 words
The process of claim 1, wherein the frequency of the supplied voltage is varied from a value below the resonant frequency to a value above the resonant frequency.
Claim 4
Dependent Claim 33 words
The process of claim 2, wherein the frequency of the supplied voltage is reduced from said frequency value above the resonant frequency value to a value below the value of the resonant frequency.
Claim 5
Dependent Claim 30 words
The process of any one of claims 1, 2 or 3, which includes the step of conducting the component to be demagnetized continuously through the magnetic field of said coil.
Claim 6
Dependent Claim 18 words
The process of any one of claims 1, 2 or 3, wherein said component is a permanent magnet.
Claim 7
Dependent Claim 27 words
The process of any one of claims 1, 2 or 3, wherein said component is a residually magnetized element resulting from incidental exposure to a magnetic field.
Claim 8
Dependent Claim 30 words
The process of any one of claims 1, 2 or 3, wherein said component is a permanent magnet, and said demagnetization is carried out only to a selectively predetermined value.
Claim 9
Dependent Claim 40 words
The process of either one of claims 2 or 3, wherein the current is supplied to the oscillator at the frequency of the commercially avilable power supply, and said supplied current is modulated by a current having a lower frequency.
Claim 10
Dependent Claim 12 words
The process of claim 8, wherein said component is a permanent magnet.
Claim 11
Dependent Claim 22 words
The process of claim 8, wherein the frequency of said modulating current is within the range of between 0.1 and 10.0 Hz.
Claim 12
Dependent Claim 12 words
The process of claim 10, wherein said component is a permanent magnet.
Claim 13
Dependent Claim 21 words
The process of claim 10, wherein said component is a residually magnetized element resulting from incidental exposure to a magnetic field.
Claim 14
Dependent Claim 24 words
The process of claim 10, wherein said component is a permanent magnet, and said demagnetization is carried out only to a selectively predetermined value.
Claim 15
Dependent Claim 22 words
The process of claim 8, wherein the frequency of said modulating current is within the range of between 0.3 and 3.0 Hz.
Claim 16
Dependent Claim 12 words
The process of claim 14, wherein said component is a permanent magnet.
Claim 17
Dependent Claim 21 words
The process of claim 14, wherein said component is a residually magnetized element resulting from incidental exposure to a magnetic field.
Claim 18
Dependent Claim 24 words
The process of claim 14, wherein said component is a permanent magnet, and said demagnetization is carried out only to a selectively predetermined value.
Claim 19
Dependent Claim 21 words
The process of claim 8, wherein said component is a residually magnetized element resulting from incidental exposure to a magnetic field.
Claim 20
Dependent Claim 24 words
The process of claim 8, wherein said component is a permanent magnet, and said demagnetization is carried out only to a selectively predetermined value.
Claim 21
Dependent Claim 23 words
The process of claim 1, which includes the step of reducing the intensity of the alternating magnetic field by reducing the supplied voltage.
Claim 22
Dependent Claim 12 words
The process of claim 20, wherein said component is a permanent magnet.
Claim 23
Dependent Claim 21 words
The process of claim 20, wherein said component is a residually magnetized element resulting from incidental exposure to a magnetic field.
Claim 24
Dependent Claim 24 words
The process of claim 20, wherein said component is a permanent magnet, and said demagnetization is carried out only to a selectively predetermined value.
Claim 25
Dependent Claim 22 words
The process of claim 1, which includes the step of withdrawing the component to be demagnetized from the vicinity of said coil.
Claim 26
Dependent Claim 31 words
The process of claim 1, wherein said oscillator comprises an LC circuit means, which includes the step of changing the resonant frequency by the addition, or substraction, of a trimmer capacitor.
Claim 27
Dependent Claim 22 words
The process of claim 25, wherein said addition, or substraction of the trimmer capacitor is controlled by control means responsive to time.

References Cited (Backward Citations)

US2445459A Cited
US3638074A Cited
US3895270A Cited
GB1481190A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-05-16 1986-11-15 1987-05-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-05-16 1990-11-15 1991-05-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-05-16 1994-11-15 1995-05-17 $7700.00 Window Closed / Lapsed

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