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US4543487A Expired / Lapsed US ⏱️ 0.0 years remaining

Procedure and means for creating an electron curtain with adjustable intensity distribution

Assignee: Stora Enso Oyj
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Filing: 1984-05-03
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Granted: 1985-09-24
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Expires: 2004-05-03
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Abstract

Abstract The invention concerns a procedure and a means for creating an electron curtain (5) intended to be used in irradiating a surface (8) and adjustable as to its intensity distribution. The electron curtain is elicited by producing with an elongated filament (2) placed in a chamber (1), free electrons in a space (6) surrounding the filament, by accelerating the electrons by means of an electrode structure (3) confining the space and by directing the electron curtain formed by the accelerated electrons out from the chamber through a window (4) permeable to electrons in its wall. It is a substantial novelty in the invention that regulation of the intensity distribution of the electron curtain (5) takes place by use of an elongated body (9) of magnetically soft material and of a row of magnets constituted by magnets (10) placed side by side, one of the two being disposed substantially parallelling the filament (2) behind the filament as seen from the direction of the window (4) of the chamber (1) and the other being disposed outside the window of the chamber before the electron curtain, the basis for the regulation achievable with the magnets being the absorption, dependent on the strength of the magnetic field, of electrons in the electrode structure (3). The magnets (10) being functionally independent of each other, the intensity of the electron curtain can be adjusted to be uniform or to vary as desired at different points of the curtain.

Inventors

  • 👤 Pertti Puumalainen
  • 👤 Rauno Rantanen
  • 👤 Pertti Sikanen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 13:39
CPC Classifications
H; H01; H01J; H01J33/00

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 171 words
Procedure for creating an electron curtain with adjustable intensity distribution, wherein by means of an elongated filament placed in a chamber are produced free electrons in a space surrounding the filament, the electrons are accelerated in said space by means of an electrode structure confining it, and the electron curtain constituted by the accelerated electrons is directed out from the chamber through a window permeable to electrons in its wall, and wherein regulation of the intensity distribution of the electron curtain takes place by use of an elongated body of magnetically soft material and of a row of magnets constituted by magnets placed side by side, one of the two being disposed substantially parallelling the filament behind the filament as seen from the direction of the window of the chamber and the other being disposed outside the window of the chamber before the electron curtain, the basis for the regulation achievable with the magnets being the absorption, dependent on the strength of the magnetic field, of electrons in the electrode structure.
Claim 2
Dependent Claim 171 words
Procedure for creating an electron curtain with adjustable intensity distribution, wherein by means of an elongated filament placed in a chamber are produced free electrons in a space surrounding the filament, the electrons are accelerated in said space by means of an electrode structure confining it, and the electron curtain constituted by the accelerated electrons is directed out from the chamber through a window permeable to electrons in its wall, and wherein regulation of the intensity distribution of the electron curtain takes place by use of an elongated body of magnetically soft material and of a row of magnets constituted by magnets placed side by side, one of the two being disposed substantially parallelling the filament behind the filament as seen from the direction of the window of the chamber and the other being disposed outside the window of the chamber before the electron curtain, the basis for the regulation achievable with the magnets being the absorption, dependent on the strength of the magnetic field, of electrons in the electrode structure.
Claim 3
Dependent Claim 26 words
Procedure according to claim 1, wherein regulation takes place by adjusting the distances between different magnets in the row and the body of magnetically soft material.
Claim 4
Dependent Claim 27 words
Procedure according to claim 1, wherein for magnets are used electromagnets and regulation takes place by adjusting the electric current intensities of different magnets in the row.
Claim 5
Dependent Claim 166 words
A means for creating an electron curtain with adjustable intensity distribution, said means comprising an elongated, electron-emitting filament, an electrode structure for accelerating the electrons and surrounding a space, and a chamber in which the filament and the electrode structure have been placed and which has in its wall a window permeable to electrons and through which the electron curtain can be directed, and said means further comprising as members regulating the intensity distribution of the electron curtain, an elongated body of magnetically soft material and a row of magnets constituted by magnets placed side by side, one of the two being disposed substantially parallelling the filament and behind the filament as seen from the direction of the window of the chamber and the other being disposed outside the window of the chamber before the electron curtain, the basis for the regulation achievable with the magnets being absorption, dependent on the strength of the magnetic field, of electrons emitted from the filament in the electrode structure.
Claim 6
Dependent Claim 166 words
A means for creating an electron curtain with adjustable intensity distribution, said means comprising an elongated, electron-emitting filament, an electrode structure for accelerating the electrons and surrounding a space, and a chamber in which the filament and the electrode structure have been placed and which has in its wall a window permeable to electrons and through which the electron curtain can be directed, and said means further comprising as members regulating the intensity distribution of the electron curtain, an elongated body of magnetically soft material and a row of magnets constituted by magnets placed side by side, one of the two being disposed substantially parallelling the filament and behind the filament as seen from the direction of the window of the chamber and the other being disposed outside the window of the chamber before the electron curtain, the basis for the regulation achievable with the magnets being absorption, dependent on the strength of the magnetic field, of electrons emitted from the filament in the electrode structure.
Claim 7
Dependent Claim 24 words
Means according to claim 4, wherein the distance of each magnet in the row from the body of magnetically soft material is independently adjustable.
Claim 8
Dependent Claim 21 words
Means according to claim 4, wherein the magnets are electromagnets, in each of them the electric current intensity being independently adjustable.
Claim 9
Dependent Claim 16 words
Means according to claim 4, wherein the wall of the chamber consists of magnetically hard material.

References Cited (Backward Citations)

US3013154A Cited
US3144552A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-09-23 1989-03-25 1989-09-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-09-23 1993-03-25 1993-09-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-09-23 1997-03-25 1997-09-24 $7700.00 Window Closed / Lapsed

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