EP0692176B1 - Gepulster röntgenstrahlgenerator - Google Patents

Gepulster röntgenstrahlgenerator Download PDF

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Publication number
EP0692176B1
EP0692176B1 EP94911991A EP94911991A EP0692176B1 EP 0692176 B1 EP0692176 B1 EP 0692176B1 EP 94911991 A EP94911991 A EP 94911991A EP 94911991 A EP94911991 A EP 94911991A EP 0692176 B1 EP0692176 B1 EP 0692176B1
Authority
EP
European Patent Office
Prior art keywords
generator
line
generator according
electric
emitting head
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 - Lifetime
Application number
EP94911991A
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English (en)
French (fr)
Other versions
EP0692176A1 (de
Inventor
Jean-Michel Pouvesle
Christophe Cachoncinlle
Raymond Viladrosa
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.)
Centre National de la Recherche Scientifique CNRS
Original Assignee
Centre National de la Recherche Scientifique CNRS
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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Publication of EP0692176A1 publication Critical patent/EP0692176A1/de
Application granted granted Critical
Publication of EP0692176B1 publication Critical patent/EP0692176B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05G—X-RAY TECHNIQUE
    • H05G1/00—X-ray apparatus involving X-ray tubes; Circuits therefor
    • H05G1/08—Electrical details
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J35/00—X-ray tubes
    • H01J35/22—X-ray tubes specially designed for passing a very high current for a very short time, e.g. for flash operation
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05G—X-RAY TECHNIQUE
    • H05G1/00—X-ray apparatus involving X-ray tubes; Circuits therefor
    • H05G1/08—Electrical details
    • H05G1/10—Power supply arrangements for feeding the X-ray tube
    • H05G1/22—Power supply arrangements for feeding the X-ray tube with single pulses
    • H05G1/24—Obtaining pulses by using energy storage devices

Definitions

  • the present invention relates to an X-ray pulse generator.
  • This known generator comprises a set of Blumleins mounted between a high voltage source, associated with a thyratron, and an X-ray emitting head.
  • the present invention solves the problem of designing an impulse X-ray generator capable of being much less bulky than this known generator.
  • the generator which is the subject of the invention is capable of emitting, over very short times (equivalent to the length of the pulse), much more intense X-ray radiation than that which is emitted by conventional generators generally used in laboratories and in industry.
  • coiled power lines allows the production of a generator of small dimensions, which can be placed on a table and which can be transported by one person.
  • the power lines of the generator object of the invention all have the same length, to obtain a good overvoltage factor.
  • the generator object of the invention may further comprise a plurality of parallel and electrically insulating supports, which are placed one beside the other and respectively associated with the lines electric coils, each support comprising a groove, in which the corresponding electric line is coiled.
  • the generator which is the subject of the invention also preferably comprises means provided for pressing the supports against each other.
  • the lines are preferably coated, in the grooves, with an electrically insulating material.
  • Each line can be wound in a spiral or double spiral.
  • each line is a flexible coaxial cable, the first and second electrical conductors of this line being respectively constituted by the core and the braid of this coaxial cable.
  • each line is a flexible coaxial cable wound in a spiral, the first and second electrical conductors of this line being respectively constituted by the core and the braid of this coaxial cable, l spiral winding of each cable is done by approaching the center of the corresponding support and the supports are drilled in their central part, to allow the passage of cables, from the side where these cables are connected to the energy storage means electric, to the supports which correspond to them respectively.
  • part of the flexible coaxial cables which are connected to the x-ray emitting head is left free to allow mobility of this emitting head relative to the rest of the generator.
  • the pulse X-ray generator which is schematically represented in FIG. 1, comprises means 2 provided for forming electrical pulses, a head 4 emitting X-rays and a cable generator 6 which connects the means 2 to the head 4.
  • the storage capacitors S1 and S2 are mounted in series, the capacitor S2 is mounted between the terminals of the high voltage source HT and the triggering means TH are also mounted between these terminals of the high voltage source HT.
  • This HV source can be a constant high voltage source or a pulse high voltage source (in which case the electrical pulse, at the input of the cable generator, is triggered when the charge of the capacitors S1 and S2 reaches a desired value) .
  • a high voltage source which can vary between 0 and 40 kV and which is capable of recharging the capacitors S1 and S2 at frequencies which can vary between 0.1 Hz and 1 kHz, depending on the desired configuration.
  • the capacitors S1 and S2 can be discrete capacitors also called “button capacitors", or can be flat lines or even coaxial cables.
  • the triggering means TH comprise a single rapid trigger, for high voltage, such as for example a thyratron or a sparkgap or a trigger known as "pseudo-spark", or another rotary spark gap, which reduces energy losses and increases efficiency.
  • triggering means are used which are capable of operating between 0.1 Hz and 1 kHz.
  • the head 4 emitting X-rays is waterproof and made of an electrically insulating material such as, for example, glass, ceramic, Plexiglas (registered trademark), polycarbonate, polyvinyl chloride or polysulfone.
  • an electrically insulating material such as, for example, glass, ceramic, Plexiglas (registered trademark), polycarbonate, polyvinyl chloride or polysulfone.
  • this emitting head 4 can be wrapped in a thin X-ray absorption envelope, which can be made of lead.
  • Pumping means 8 communicate in leaktight manner with the interior of the emitting head 4 in order to create a vacuum there.
  • the duration of an X-ray pulse is a function of the residual pressure inside the emitting head 4.
  • This emitting head 4 is provided with an anode 10 and a cathode 12 which are placed opposite one another in the emitting head 4 and which pass through the walls of the latter by sealed passages.
  • the emitting head 4 is provided with an orifice 14 facing the space between the anode and the cathode, to allow the exit of the X-ray referenced 16.
  • This orifice 14 is closed in a leaktight manner using a thin waterproof wall 18 and made of a material transparent to the generated X-rays.
  • the nature of the material constituting the anode determines the spectrum of the X-ray radiation emitted by this anode as well as the braking radiation of the electrons emitted by the cathode, which will be discussed below.
  • the cathode one chooses a material able to easily supply electrons like for example copper or graphite and, for the anode, one can choose a metallic constituent material like for example copper, molybdenum, tungsten or silver .
  • the relative position of the anode and the cathode determines the shape of the X-ray emission lobe and the spatial distribution of these X-rays.
  • the spacing E between the anode and the cathode can be made adjustable.
  • the anode 10 can be made rotating by providing it with a rotation means symbolized by the arrow F in FIG. 1.
  • this anode 10 can be provided with means R for cooling by circulation of an appropriate fluid.
  • the cable generator 6 comprises at least two electric lines preferably constituted by flexible coaxial cables (which are six in number in the example shown in FIG. 1 and bear the references C1, C2, C3, C4, C5 and C6).
  • Each coaxial cable comprises a first electrical conductor A called “core” and a second electrical conductor T called “braid” which surrounds the core A and is separated from it by a dielectric D.
  • each cable is surrounded by an electrically insulating envelope, not shown.
  • These flexible coaxial cables are connected in parallel to the means for producing electrical pulses 2 and connected in series to the transmitting head.
  • the ends of the cores of the coaxial cables are electrically connected to each other as well as to the terminal a of the capacitor S2.
  • the braids of the coaxial cables are electrically connected to each other as well as to the terminal b of the capacitor S1, the terminal common to the capacitors S1 and S2 bearing the reference c , as seen in FIG. 1.
  • the end of the core of the coaxial cable C6 is electrically connected to the anode 10 while the end of the braid of the coaxial cable C1 is electrically connected to the cathode 12 and the end of the braid of the coaxial cable C6 is electrically connected to the end of the core of the coaxial cable C5 while the end of the braid of this coaxial cable C5 is electrically connected to the end of the core of the coaxial cable C4 ... and the end of the braid of the coaxial cable C2 is electrically connected to the end of the core of the coaxial cable C1.
  • TH trigger releases electrical energy stored in capacitors S1 and S2 and to transfer part of this electrical energy to the cable generator 6.
  • This cable generator 6 allows the multiplication of the electric voltage of the pulse supplied by the means 2, the multiplying factor being a function of the number of flexible coaxial cables.
  • a voltage of 60 kV is obtained between the anode and the cathode of the X-ray emitting head.
  • An 80 kV voltage would be obtained using eight coaxial cables and the same 10 kV input voltage, or alternatively using six coaxial cables but an input voltage of 13.3 kV.
  • FIGS 2 and 3 illustrate the arrangement of the coaxial cables C1 to C6.
  • coaxial cables C1 to C6 are respectively mounted on electrically insulating plates P1 to P6 (for example made of polyvinyl chloride).
  • each flexible coaxial cable is wound on the plate associated with it.
  • each coaxial cable is wound in a spiral in a groove G (FIG. 3) provided for this purpose on one face of the corresponding plate.
  • the plates P1 to P6 are stacked from the plate P1 to the plate P6, as seen in FIG. 3 which is a top view of the stack obtained.
  • the faces of the plates carrying the grooves G in a spiral are all turned on the same side of the stack.
  • an electrically insulating protective plate P7 for example made of polyvinyl chloride, is placed opposite the face of the plate P1 carrying the corresponding spiral groove.
  • the plates P1 to P7 are pressed against each other (so that there is no air between them, which limits the Corona effect), using appropriate means which, in the example shown on FIG. 3 are electrically insulating threaded rods 20, for example made of polyvinyl chloride, which pass through aligned holes 21 of the plates P1 to P6, the end of each rod situated on the side of the plate P6 being provided with a head 22 which presses against this plate P6 while the other end of each threaded rod is provided with a nut 23 which clamps the plates against each other by means of an electrically insulating washer 24 as are nut 23 and head 22.
  • electrically insulating threaded rods 20 for example made of polyvinyl chloride
  • the coaxial cables are coated, in their respective grooves, with an electrically insulating paste P, for example silicone.
  • the six cables arrive from their connections in parallel, towards the face of the plate P7 which does not carry a groove.
  • the plate P1 has an orifice 01
  • the plate P2 has two orifices O1 and O2, ...
  • the plate P6 has six orifices C1 to O6.
  • the distance between two adjacent holes is the same for each of the plates.
  • the cable C1 crosses the six openings O1 to wind in a spiral on the plate P1
  • the cable C2 crosses the five openings 02 to wind on the plate P2
  • the cable C6 crosses the opening 06 to wind on the plate P6.
  • the flexible coaxial cables are all the same length.
  • the length of the spiral portion closest to the center of a plate is calculated according to the thickness of the assembly to be crossed for the corresponding cable.
  • FIG. 2 illustrates this: we see that this portion increases from cable C1 to cable C6 so that there remains a greater length for the cable C1, allowing this cable C1 to pass through the assembly, than for the cable C6 which is closest to the parallel connections of the coaxial cables.
  • a sufficient thickness of insulating material must be provided between the adjacent cables and between the adjacent turns of the spiral of each cable so as not to have electrical breakdown during operation of the generator.
  • the generator which has been described with reference to FIGS. 1 to 3 leads to an exposure time of 20 ns whereas a conventional generator (conventional X tube) requires an exposure time 6 s, for the same dose of X-radiation received at the same distance.
  • each of the flexible coaxial cables such as the cable C1 is wound in a double spiral as shown in FIG. 4, in a groove provided for this purpose on one face of the corresponding plate.
  • FIG. 5 is a schematic view of another embodiment of the X-ray emitting head.
  • the emitter head of FIG. 5 has a symmetry of revolution about a Z axis and includes an annular anode 10 provided with a bore along the Z axis as well as a cathode 12 of elongated shape along the Z axis and finished by a point opposite the piercing of the anode.
  • the cathode 12 is adjustable in translation along the Z axis in an internally threaded part 28, the cathode having a corresponding external thread.
  • This part 28 is housed in an electrically insulating tube 30 of axis X, one end of which is closed by an external shoulder of the part 28 while the other end of the tube 30 is closed by the anode 10.
  • the emitting head On the side thereof, the emitting head is extended by a tubular piece 32 of electrically conductive axis X, which is in contact with the anode and closed in leaktight manner by a thin wall 18 transparent to the generated X-rays and which delimits a zone communicating with pumping means 8 making it possible to create a vacuum in the emitting head, the parts 28 and 32 comprising seals 34 for maintaining the vacuum.
  • FIG. 5 also shows electrical conductors 36 by which the anode and the cathode are connected to the cable generator 6.
  • the assembly of the generator according to the invention which has been described with reference to FIGS. 1 to 5, can be reduced to a size and a weight which are compatible with use in a portable generator.

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  • X-Ray Techniques (AREA)

Claims (10)

  1. Gepulster Röntgenstrahlgenerator, umfassend:
    - eine Hochspannungsquelle (HT),
    - einen Röntgenstrahl-Emissionskopf (4), der Röntgenstrahlen erzeugen kann, wenn er einen elektrischen Impuls empfängt, und
    - eine Vielzahl elektrischer Leitungen (C1 bis C6), enthalten zwischen der Hochspannungsquelle und dem Röntgenstrahl-Emissionskopf, wobei jede elektrische Leitung einen ersten elektrischen Leiter (A) und einen zweiten elektrischen Leiter (T) umfaßt, die durch ein Dielektrikum (D) getrennt sind,
    und dieser Generator außerdem umfaßt:
    - Speichereinrichtungen (S1, S2) für elektrische Energie, geliefert durch die Hochspannungsquelle (HT), und
    - Auslösungseinrichtungen (TH), um die in den Speichereinrichtungen (S1, S2) gespeicherte elektrische Energie freizugeben und den elektrischen Impuls auszulösen, der dann über die elektrischen Leitungen (C1 bis C6) zum Röntgenstrahl-Emissionkopf (4) übertragen wird,
    wobei diese elektrischen Leitungen gewickelt sind und einerseits parallel mit den elektrischen Energiespeichereinrichtungen (S1, S2) verbunden sind und andererseits in Serienschaltung mit dem Röntgenstrahl-Emissionskopf (4).
  2. Generator nach Anspruch 1, dadurch gekennzeichnet, daß die elektrischen Leitungen (C1 bis C6) alle dieselbe Länge haben.
  3. Generator nach einem der Ansprüche 1 und 2, dadurch gekennzeichnet, daß er außerdem eine Vielzahl paralleler und elektrisch isolierender Träger (P1 bis P6) umfaßt, die nebeneinander angeordnet sind und jeweils den gewickelten elektrischen Leitungen (C1 bis C6) zugeordnet sind, wobei jeder Träger eine Hohlkehle bzw. Rille (G) aufweist, in der die entsprechende elektrische Leitung gewickelt ist.
  4. Generator nach Anspruch 3, dadurch gekennzeichnet, daß er außerdem Einrichtungen (20, 22, 23, 24) umfaßt, vorgesehen, die Träger (P1 bis P6) gegeneinanderzudrücken.
  5. Generator nach einem der Ansprüche 4 und 5, dadurch gekennzeichnet, daß die Leitungen in den Rillen (G) mit einem elektrisch isolierenden Material (P) umhüllt werden.
  6. Generator nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß jede Leitung (C1 bis C6) spiralförmig gewickelt ist.
  7. Generator nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß jede Leitung (C1 bis C6) doppelspiralförmig gewickelt ist.
  8. Generator nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß jede Leitung ein biegsames Koaxialkabel (C1 bis C6) ist, wobei der erste und der zweite elektrische Leiter dieser Leitung jeweils gebildet wird durch den Kern (A) und die Beflechtung (T) des Koaxialkabels.
  9. Generator nach einem der Ansprüche 3 bis 5, dadurch gekennzeichnet, daß jede Leitung (C1 bis C6) spiralförmig gewickelt ist, dadurch, daß jede Leitung ein biegsames Koaxialkabel ist, wobei der erste und der zweite elektrische Leiter dieser Leitung jeweils gebildet wird durch den Kern (A) und die Beflechtung (T) des Koaxialkabels, dadurch, daß die spiralförmige Wicklung jedes Kabels erfolgt, indem man sich dem Zentrum des entsprechenden Trägers (P1 bis P6) nähert, und dadurch, daß die Träger in ihrem zentralen Teil durchbohrt sind, um den Durchgang der Kabel von der Seite aus, wo diese Kabel mit den Speichereinrichtungen für elektrische Energie (S1, S2) verbunden sind, zu den ihnen jeweils entsprechenden Trägern (P1 bis P6) zu ermöglichen.
  10. Generator nach einem der Ansprüche 8 und 9, dadurch gekennzeichnet, daß ein Teil dieser biegsamen Koaxialkabel, die mit dem Röntgenstrahl-Emissionskopf (4) verbunden sind, frei gelassen wird, um die Beweglichkeit dieses Emissionskopfes in bezug auf den Rest des Generators zu ermöglichen.
EP94911991A 1993-03-30 1994-03-29 Gepulster röntgenstrahlgenerator Expired - Lifetime EP0692176B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9303670 1993-03-30
FR9303670A FR2703556B1 (fr) 1993-03-30 1993-03-30 Générateur impulsionnel de rayons X.
PCT/FR1994/000349 WO1994023552A1 (fr) 1993-03-30 1994-03-29 Generateur impulsionnel de rayons x

Publications (2)

Publication Number Publication Date
EP0692176A1 EP0692176A1 (de) 1996-01-17
EP0692176B1 true EP0692176B1 (de) 1997-07-09

Family

ID=9445505

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94911991A Expired - Lifetime EP0692176B1 (de) 1993-03-30 1994-03-29 Gepulster röntgenstrahlgenerator

Country Status (5)

Country Link
US (1) US5651045A (de)
EP (1) EP0692176B1 (de)
DE (1) DE69404139T2 (de)
FR (1) FR2703556B1 (de)
WO (1) WO1994023552A1 (de)

Families Citing this family (13)

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Publication number Priority date Publication date Assignee Title
US6064718A (en) * 1998-09-29 2000-05-16 The United States Of America As Represented By The Secretary Of The Navy Field emission tube for a mobile X-ray unit
WO2001084712A1 (en) * 2000-05-01 2001-11-08 Ion Physics Corporation Application of voltage pulses to certain types of electrical loads
US6985557B2 (en) * 2002-03-20 2006-01-10 Minnesota Medical Physics Llc X-ray apparatus with field emission current stabilization and method of providing x-ray radiation therapy
DE20218138U1 (de) 2002-11-21 2004-04-08 Heuft Systemtechnik Gmbh Röntgenanlage zur Erzeugung von kurzen Röntgenstrahlenimpulsen und mit einer solchen Röntgenanlage arbeitende Inspektionsvorrichtung
US7615931B2 (en) 2005-05-02 2009-11-10 International Technology Center Pulsed dielectric barrier discharge
US7502446B2 (en) * 2005-10-18 2009-03-10 Alft Inc. Soft x-ray generator
JP5791401B2 (ja) * 2011-07-11 2015-10-07 キヤノン株式会社 放射線発生装置及びそれを用いた放射線撮影装置
US9826610B2 (en) 2014-07-23 2017-11-21 Moxtek, Inc. Electrostatic-dissipation device
US9779847B2 (en) 2014-07-23 2017-10-03 Moxtek, Inc. Spark gap X-ray source
US9839107B2 (en) 2014-07-23 2017-12-05 Moxtek, Inc. Flowing-fluid X-ray induced ionic electrostatic dissipation
US9839106B2 (en) 2014-07-23 2017-12-05 Moxtek, Inc. Flat-panel-display, bottom-side, electrostatic-dissipation
US10524341B2 (en) 2015-05-08 2019-12-31 Moxtek, Inc. Flowing-fluid X-ray induced ionic electrostatic dissipation
US20170013702A1 (en) * 2015-07-10 2017-01-12 Moxtek, Inc. Electron-Emitter Transformer and High Voltage Multiplier

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US3363102A (en) * 1965-01-25 1968-01-09 Field Emission Corp High voltage pulse transmission system employing field emission diodes for successively pulsing a load
US3681604A (en) * 1970-08-17 1972-08-01 Bendix Corp Portable x-ray generating machine
IL42776A0 (en) * 1972-08-31 1973-10-25 Bendix Corp Spiral generators
US4070579A (en) * 1976-08-19 1978-01-24 Hewlett-Packard Company X-ray tube transformer
US4289969A (en) * 1978-07-10 1981-09-15 Butler Greenwich Inc. Radiation imaging apparatus
US4578805A (en) * 1984-10-10 1986-03-25 Maxwell Laboratories, Inc. Transmission line transmitting energy to load in vacuum chamber

Also Published As

Publication number Publication date
DE69404139T2 (de) 1998-01-15
FR2703556B1 (fr) 1995-05-19
US5651045A (en) 1997-07-22
FR2703556A1 (fr) 1994-10-07
WO1994023552A1 (fr) 1994-10-13
EP0692176A1 (de) 1996-01-17
DE69404139D1 (de) 1997-08-14

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