EP1584220B1 - High-voltage supply for an x-ray device - Google Patents

High-voltage supply for an x-ray device Download PDF

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Publication number
EP1584220B1
EP1584220B1 EP03785820A EP03785820A EP1584220B1 EP 1584220 B1 EP1584220 B1 EP 1584220B1 EP 03785820 A EP03785820 A EP 03785820A EP 03785820 A EP03785820 A EP 03785820A EP 1584220 B1 EP1584220 B1 EP 1584220B1
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EP
European Patent Office
Prior art keywords
voltage
ray
line
ray tube
resistors
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Expired - Lifetime
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EP03785820A
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German (de)
French (fr)
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EP1584220A2 (en
Inventor
Werner Kühnel
Walter Beyerlein
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Siemens AG
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Siemens AG
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    • 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
    • H05G1/26—Measuring, controlling or protecting
    • H05G1/54—Protecting or lifetime prediction
    • 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
    • H05G1/12—Power supply arrangements for feeding the X-ray tube with dc or rectified single-phase ac or double-phase

Definitions

  • the invention relates to a high-voltage supply for an X-ray device, which consists essentially of electrical lines which are arranged between a high-voltage circuit and an X-ray tube of the X-ray device.
  • X-ray tubes are constructed as high-vacuum tubes.
  • the high vacuum prevents flashovers between the cathode and the anode of the x-ray tube when the x-ray voltage is applied, which is in the kilovolt range.
  • small amounts of residual gases polluting the high vacuum are inevitable. This is especially true because in the course of operation of the X-ray tube gaseous material components emerge inside the tube.
  • the residual gases can be ionized by the x-ray voltage. The ionization causes flashover and thus short-circuiting within the X-ray tube.
  • the object of the invention is to provide an X-ray device in which interference signals and overvoltages that occur due to short circuits in the X-ray tube are so strongly attenuated that malfunction of the electronics and component damage within the X-ray device are avoided, and at the same time power losses of Cathode heating current can be kept low.
  • the invention solves this problem by an X-ray device with the features of the first claim.
  • a basic idea of the invention is to damp vibrations and interference signals in the high-voltage supply of the X-ray device, that is to say between the X-ray generator and the X-ray tube.
  • the attenuation is accomplished by providing termination resistors on the high voltage lines of the high voltage supply. An attenuation by terminating resistors is particularly uncomplicated and easy to implement.
  • a heating current transformer is connected to the X-ray tube via additional filter inductors arranged in parallel with the cathode-side termination resistor.
  • An advantageous embodiment of the invention results when the high-voltage lines of the high-voltage supply are not provided at both ends, but only at one end, so one-sided, with a terminating resistor.
  • a one-sided termination resistor can namely cause a sufficiently rapid decay of the interference signals.
  • a particularly advantageous variant of this embodiment results from the fact that the one-sided terminating resistor is arranged in each case on the X-ray tube side of each high-voltage line. As a result, it is possible to maintain the high output impedance of the X-ray generator to be observed for operation.
  • the impedance of the terminating resistors is adapted to the line impedance of the respective line. Adequate damping is obtained in particular if the impedance of the terminating resistors corresponds to the impedance of the high-voltage lines.
  • FIG. 1 shows the basic structure of the high voltage circuit of an X-ray device according to the prior art.
  • a primary voltage generator 3 generates a primary voltage, which is forwarded to high-voltage transformers 5 and transformed by them into a high voltage which is sufficient for the operation of the X-ray tube.
  • the high voltage supplied by the high-voltage transformers 5 is forwarded to the components 7, in which a rectifier diode and a smoothing capacitor are indicated, rectified and smoothed by these.
  • the components 7 deliver the high voltage to the damping resistors 9 (R D ).
  • the damping resistors 9 (RD) have to protect the X-ray generator 1 largely from surges and interference signals from the high voltage supply the task. They usually have values on the order of a few kilo-ohms.
  • the x-ray tube 15 is connected to the x-ray generator 1 through an intermediate high-voltage supply, the high-voltage supply consisting essentially of an anodic coaxial high-voltage line 11 and a cathodic coaxial high-voltage line 13.
  • the coaxial structure of the high-voltage lines 11 and 13 is indicated by the graphic representation as a box instead of a line.
  • the anodic high-voltage line 11 connects the output of the X-ray generator 1 with the anode 17 of X-ray tube 15. Analogously connects the cathodic high-voltage line 13, the cathode 19 of the X-ray tube 15.
  • the X-ray tube 15 may be two-beam, ie, designed as a two-focus tube, so the cathode 19 is shown by way of hint with two coils.
  • the two coils of the cathode 19 are supplied by the heating transformer 21 with heating current.
  • FIG. 2 shows a schematic representation of the high voltage circuit of an X-ray device according to the prior art.
  • the generator 31 the x-ray voltage U 0 is generated and delivered via the damping resistors 9 (R D ) to the high-voltage lines 11 and 13.
  • the voltage is applied to the X-ray tube, which is shown here as a load resistor 33 (R L ).
  • the high voltage circuit is shown during operation, ie in steady state.
  • the anodic high-voltage line 11 is at its entire length at potential U 0
  • the cathodic high-voltage line 13 is on its entire length to -U 0 volts.
  • FIG. 1 shows a schematic representation of the high voltage circuit of an X-ray device according to the prior art.
  • FIG. 3 shows the same schematic representation of the high voltage circuit according to the prior art as the previous one FIG. 2 with the same reference numerals.
  • FIG. 3 However, the high-voltage circuit at another time, namely immediately after the occurrence of a short circuit in the X-ray tube.
  • the diverging waves hit impedance jumps both left and right.
  • the damping resistors 9 R D
  • this is the short circuit in the X-ray tube, ie the load resistor 33 (R L ), which has assumed the value R L 0.
  • the reflected waves then converge, encounter each other, and diverge again until they are reflected back to the discontinuity of the line impedance.
  • the high-voltage line assumes the voltage 0 over the entire length, the voltage -U 0 after half of the oscillation period and again the voltage 0 after three quarters of the oscillation period, until the oscillation process is repeated after a complete oscillation period begin.
  • the oscillation continues basically endlessly, but is dampened in reality by line losses.
  • FIG. 4 1 shows the anodic side of a high voltage circuit of an X-ray device with rectification and attenuation device 7, attenuation resistor 9 (R D ), grounded coaxial high voltage line 11, and X-ray tube 15.
  • This conventional construction is supplemented by termination resistor 37 (FIG. R A ) terminating the X-ray generator side end of the high voltage line 11, and the termination resistor 38 (R A ) terminating the X-ray tube side end of the high voltage line 11.
  • the termination resistors 37, 38 (R A ) are connected in parallel, so they lie between the respective end of the high voltage line 11 and the ground 23. They can be connected by soldering.
  • the termination resistors 39 R A therefore have a value of about 45 ohms, since their damping effect becomes optimal when their impedance corresponds to that of the high voltage lines 11, 13.
  • high-voltage smoothing capacitances 41 (C H ) connected in series between them and the ground 23.
  • the purpose of the high-voltage smoothing capacitances 41 (C H ) is to allow high-frequency interference signals and overvoltages to pass to ground 23, but to block low-frequency and DC useful signals. They serve that is, as a high-pass filter whose frequency is to be selected such that interference signals can flow away to the ground, but no power loss occurs with respect to useful signals.
  • the high voltage smoothing capacitances 41 (C H ) also prevent the X-ray tube end termination resistor 38 (R A ) from being shorted by the short circuit in the X-ray tube 15 and therefore remain ineffective.
  • C H capacitances
  • FIG. 5 shows a variant of the circuit in departure from the parallel connection of the terminating resistors. Shown is the rectifier and attenuation component 7, the coaxial high-voltage line 11 including grounding 23 and the X-ray tube 15. Also shown are the terminating resistors 39 (R A ), but this time in series between the high-voltage line 11 and the device 7 and between the high-voltage line 11 and the X-ray tube 15.
  • the X-ray generator-side low-impedance termination resistor 39 (R A ) replaces the normally provided high-impedance damping resistor R D , the component 7 and the other subsequent, in of the FIG. 5 not shown, X-ray generator protects against overvoltages.
  • the termination resistor 39 (R A ), which is on the order of tens of ohms, does not offer the same protection against overvoltages in the x-ray generator 1 X-ray generator 1 would therefore have to be sufficiently robust to withstand 15 currents in the kilo-ampere range in the event of a short circuit in the X-ray tube.
  • the terminating resistors 39 do not have the same impedance as the high-voltage lines 11, 13 to be terminated, but the double impedance or more, ie at least 90 ohms.
  • the double impedance or more ie at least 90 ohms.
  • a disadvantage is the higher sustained loss conduction, as caused by the drop in high voltage across the termination resistors 39 (R A ).
  • R A termination resistors 39
  • FIG. 6 shows a high voltage circuit according to the invention improved under the aspects described.
  • a compromise is realized in terms of the terminating resistors, as here both the high-voltage anodic line 11 and the cathodic high-voltage line 13 are terminated only on one side by a terminating resistor 39 (R A ).
  • the impedance of the terminating resistors 39 (R A ) is approximately equal to the line impedance of the high voltage lines 11 and 13, that is about 45 ⁇ .
  • the FIG. 6 shows the X-ray generator 1, therein the primary voltage generator 3, the high-voltage transformers 5, the rectifier and damping components 7, the damping resistors 9 (R D ) and the heating current transformer 21.
  • the X-ray generator 1 is connected to the ground 23rd connected coaxial high-voltage lines 11 and 13 connected to the X-ray tube 15.
  • the termination resistors 39 (R A ) are connected in series between the high voltage lines 11 and 13 and the X-ray tube 15. The only one-sided completion of the high-voltage lines 11 and 13 prevents the occurrence of a permanent vibration in the event of a short circuit in the X-ray tube 15th
  • the cathode On the cathodic high voltage side, the peculiarity arises that the cathode is supplied not only the negative part of the X-ray tube voltage, but also the heating current for the cathode.
  • a terminating resistor were also inserted in the heating current supply, unacceptably high losses in the heating current - which would amount to a few amperes after all - would be caused.
  • the three termination resistors on the lines would be connected in parallel, they would have to have a resistance value three times greater than the single termination resistor 39 (R A ), which would even triple the heating current losses.
  • additional filter inductors 40 are introduced instead of terminating resistors.
  • These additional filter inductors 40 are designed as current-compensated chokes and usually connected by soldering. They have the task of blocking the high-frequency interference signals in the high-voltage line 13, however, to allow the low-frequency heating current to happen. As such, they provide low-pass filtering. For this purpose, they are arranged in series between the x-ray tube 15 and the high voltage line 13 and the heating current transformer 21 and in parallel with the terminating resistor 39 (R A ).
  • the size of the filter inductors 40 is to be sized depending on the noise in the high voltage line 13 and 11 respectively. Since the spurious signals move in the megahertz range, the heating current usually in the kilohertz range, the filter inductors 40 are sized with a size of about 50 micro-Henry.
  • FIG. 7 shows a further variant, which is substantially changed with respect to the supply of the cathode with heating current.
  • FIG. 7 shows the high voltage circuit with the X-ray generator 1 and the already known from the previous figures internal assemblies.
  • the anodic high-voltage line 11 and the cathodic high-voltage line 13 are connected, these in turn are connected in series with the terminating resistors 39 (R A ).
  • the heating current transformer 21 is disposed in the periphery of the X-ray tube 15, such as in the X-ray generator 1 or within the high-voltage tank surrounding the X-ray tube 15 to protect the environment from high voltage and radiation.
  • the heating current transformer 21 is in FIG. 7 disposed within the x-ray tube 15. Thereby, the heating current transformer 21 is decoupled from the disturbances in the high voltage line 13 from the outset. There is therefore no need to arrange additional filter inductors for filtering overvoltages or noise before the heating power supply.
  • FIG. 8 shows a further variant of the high voltage circuit, in which the high-voltage lines 11 and 13 are also each provided on one side with terminating resistors 39 (R A ).
  • FIG. 8 shows the X-ray generator 1 with the damping resistors 9 (R D ) and otherwise the same components as in the preceding figures.
  • R A the termination resistors 39
  • the termination resistors 39 (R A ) are connected in series between the high voltage lines 11 and 13 and the X-ray generator 1.
  • damping resistors which are dimensioned in-the usual order of a few kilo-ohms.
  • the terminal resistors 39 (R A) are thus in addition to the damping resistors 9 (R D) provided inside the X-ray generator. 1
  • high-voltage smoothing capacitances 41 (C H ) are provided, usually ceramic or foil capacitors, which are connected by soldering become.
  • the high-voltage smoothing capacitances 41 (C H ) are connected to the respective connection point between the snubber resistors 9 (R D ) and the termination resistors 39 (R A ) and to the respective ground 23. They are thus connected in parallel with the damping resistors 9 (R D ) and in parallel with the terminating resistors 39 (R A ).
  • the high-voltage lines 11 and 13 are completed in this variant of the circuit with the series connection of the respective terminating resistors 39 (R A ) and the respective high-voltage smoothing capacitor 41 (C H ).
  • the high-voltage smoothing capacitances 41 (C H ) must be made large enough to be equalized in the high-voltage lines 11 and 13 to act low impedance.
  • this variant of the circuit is of interest in particular in X-ray devices in whose high-voltage circuit a large high-voltage smoothing capacitance is provided from the outset.
  • FIG. 9 shows a simulation of the voltage curve at the cathode of a conventional high voltage circuit of an X-ray device, as shown in FIG. 1 is shown.
  • the cathodic high voltage is plotted over time, assuming an x-ray typical high voltage of 100 kilo-volts.
  • a short circuit in the X-ray tube is simulated, which is clearly visible at the collapse of the cathodic voltage.
  • the short begins abruptly and ends abruptly at 300 nano-seconds.
  • Shown are two voltage waveforms, one of which is at the beginning of the high voltage line 13 is tapped, the other at the end of the high-voltage line 13.
  • Clearly visible are strong interference signals that continue after the end of the short circuit for a long time and with significant Kochspanhungsspitzen. During the occurrence of these disturbances an operation of the X-ray tube would not be meaningfully possible or component defects could occur.
  • FIG. 10 shows the same simulation on the basis of a circuit according to the invention as shown in FIG. 6 is shown. Shown again is the cathodic voltage over time. The two voltage curves again represent the voltage at the beginning or at the end of the high-voltage line 13. At 50 ns abruptly sets in the X-ray tube, which ends just as abruptly at 300 ns. After the end of the short circuit, overvoltages and interfering signals are completely eliminated. Instead, the cathodic voltage, attenuated by the termination resistance and the filter inductances, gradually increases again. After about 7 microseconds, a time in FIG. 10 is no longer shown, the cathode reaches the operating voltage again.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • X-Ray Techniques (AREA)
  • Apparatus For Radiation Diagnosis (AREA)
  • Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)

Abstract

The disclosed, embodiments relate to a high-voltage supply ( 11, 13, 23 ) for an X-ray device. The X-ray device comprises an X-ray tube ( 15 ) and a high voltage generator( 1 ), for generation of the high voltage necessary for operating the X-ray tube ( 15 ). The high voltage supply ( 11, 13, 23 ) comprises electrically-conducting lines ( 11, 13 ), for the connection of the high voltage generator to the X-ray tube ( 15 ). Each of the lines ( 11, 13 ) comprises one end which may be connected to the high voltage generator ( 1 ) and a further end which may be connected to the X-ray tube ( 15 ). At least one end of at least one of the lines ( 11, 13 ) may be connected to an electrical terminal resistor ( 39 ) which may be arranged between the line ( 11, 13 ) and the high voltage generator ( 1 ), or between the line ( 11, 13 ) and the X-ray tube ( 15 ).

Description

Die Erfindung betrifft eine Hochspannungs-Versorgung für eine Röntgeneinrichtung, die im wesentlichen aus elektrischen Leitungen besteht, die zwischen einem Hochspannungskreis und einer Röntgenröhre der Röntgeneinrichtung angeordnet sind.The invention relates to a high-voltage supply for an X-ray device, which consists essentially of electrical lines which are arranged between a high-voltage circuit and an X-ray tube of the X-ray device.

Röntgenröhren sind als Hochvakuumröhren aufgebaut. Durch das Hochvakuum werden Überschläge zwischen der Kathode und der Anode der Röntgenröhre bei Anlegen der Röntgenspannung, die sich im Kilo-Volt-Bereich bewegt, grundsätzlich verhindert. Geringe Mengen an Restgasen, die das Hochvakuum verunreinigen, sind jedoch unvermeidlich. Dies gilt insbesondere deshalb, weil im Laufe des Betriebs der Röntgenröhre gasförmige Materialbestandteile im Inneren der Röhre austreten. Die Restgase können durch die Röntgenspannung ionisiert werden. Durch die Ionisation kommt es zum Überschlag und damit zum Kurzschluss innerhalb der Röntgenröhre.X-ray tubes are constructed as high-vacuum tubes. The high vacuum prevents flashovers between the cathode and the anode of the x-ray tube when the x-ray voltage is applied, which is in the kilovolt range. However, small amounts of residual gases polluting the high vacuum are inevitable. This is especially true because in the course of operation of the X-ray tube gaseous material components emerge inside the tube. The residual gases can be ionized by the x-ray voltage. The ionization causes flashover and thus short-circuiting within the X-ray tube.

Die zeitlichen Verläufe der Kurzschlussströme und der dadurch verursachten Vorgänge zum Ladungsausgleich in der Leitungen der Hochspannungs-Versorgung weisen teilweise sehr hohe Flankensteilheiten auf, da sie sehr schnell ablaufen. Das resultierende Störspektrum reicht daher bis in den oberen Mega-Hertz-Bereich hinein und ist sehr breitbandig. Zudem verursachen die Kurzschluss- und Ladungsausgleich-Ströme mit Überspannungen verbundene Schwingungen, die nur sehr langsam abklingen.The temporal courses of the short-circuit currents and the resulting charge balance processes in the lines of the high-voltage supply sometimes have very high edge slopes, since they run very fast. The resulting interference spectrum therefore extends into the upper megahertz range and is very broadband. In addition, the short circuit and charge balancing currents cause overvoltages associated oscillations that decay only very slowly.

Durch derartige Störsignale und Überspannungen im Hochspannungskreis der Röntgeneinrichtung kann es zu Funktionsstörungen der Elektronik und der Computereinrichtung kommen. Häufig treten auch Bauteilausfälle auf, vor allem im Hochspannungskreis des Röntgengenerators. Neben Ausfallzeiten beim Betrieb und kostspieligen Schäden an der Röntgeneinrichtung verursachen die Störungen auch eine erhöhte Strahlungsbelastung der zu untersuchenden Patienten, die aufgrund von Anlagenausfällen wiederholt untersucht werden müssen.Such interference signals and overvoltages in the high-voltage circuit of the X-ray device can lead to malfunctions of the electronics and of the computer device. Frequently, component failures also occur, especially in the high-voltage circuit of the X-ray generator. In addition to downtime during operation and cause costly damage to the X-ray device the disorders also an increased radiation exposure of the patients to be examined, which must be repeatedly examined due to system failures.

Aus der EP 0 497 517 ist eine Röntgeneinrichtung bekannt, bei der je ein die elektrische Spannung begrenzender Widerstand auf jeder Seite der Röntgenröhre zur Masse hin vorgesehen ist. Besagte Widerstände verursachen jedoch Leistungsverluste im Heizstrom zur Beheizung der Kathode.From the EP 0 497 517 An X-ray device is known in which a voltage limiting the electrical resistance on each side of the X-ray tube is provided to the mass. However, said resistances cause power losses in the heating current for heating the cathode.

Aus der DE 24 02 125 und der JP 54090987 sind ebenfalls Röntgeneinrichtungen bekannt, bei denen spannungsbegrenzende Bauelemente vorgesehen sind, ohne dass dabei der KathodenHeizstrom berücksichtigt würde.From the DE 24 02 125 and the JP 54090987 X-ray devices are also known in which voltage-limiting components are provided, without taking into account the cathode Heizstrom.

Aufgabe der Erfindung ist es, eine Röntgeneinrichtung anzugeben, bei der Störsignale und Überspannungen, die aufgrund von Kurzschlüssen in der Röntgenröhre auftreten, so stark gedämpft werden, dass Funktionsstörungen der Elektronik und Bauteilbeschädigungen innerhalb der Röntgeneinrichtung vermieden werden, und bei der gleichzeitig Leistungs-Verluste eines Kathoden-Heizstroms gering gehalten werden.The object of the invention is to provide an X-ray device in which interference signals and overvoltages that occur due to short circuits in the X-ray tube are so strongly attenuated that malfunction of the electronics and component damage within the X-ray device are avoided, and at the same time power losses of Cathode heating current can be kept low.

Die Erfindung löst diese Aufgabe durch eine Röntgeneinrichtung mit den Merkmalen des ersten Patentanspruchs.The invention solves this problem by an X-ray device with the features of the first claim.

Ein Grundgedanke der Erfindung besteht darin, Schwingungen und Störsignale in der Hochspannungs-Versorgung der Röntgeneinrichtung, also zwischen Röntgengenerator und Röntgenröhre, zu dämpfen. Die Dämpfung wird durch Vorsehen von Abschluss-Widerständen an den Hochspannungs-Leitungen der Hochspannungs-Versorgung bewirkt. Eine Dämpfung durch Abschluss-Widerstände ist besonders unaufwändig und einfach realisierbar. Ein Heizstrom-Transformator wird über zusätzliche Filter-Induktivitäten, die parallel zu dem kathodenseitigen Abschluss-Widerstand angeordnet sind, mit der Röntgenröhre verbunden.A basic idea of the invention is to damp vibrations and interference signals in the high-voltage supply of the X-ray device, that is to say between the X-ray generator and the X-ray tube. The attenuation is accomplished by providing termination resistors on the high voltage lines of the high voltage supply. An attenuation by terminating resistors is particularly uncomplicated and easy to implement. A heating current transformer is connected to the X-ray tube via additional filter inductors arranged in parallel with the cathode-side termination resistor.

Eine vorteilhafte Ausgestaltung der Erfindung ergibt sich, wenn die Hochspannungs-Leitungen der Hochspannungs-Versorgung nicht an beiden Enden, sondern lediglich an einem Ende, also einseitig, mit einem Abschluss-Widerstand versehen sind. Bereits ein einseitiger Abschluss-Widerstand kann nämlich ein ausreichend schnelles Abklingen der Störsignale bewirken.An advantageous embodiment of the invention results when the high-voltage lines of the high-voltage supply are not provided at both ends, but only at one end, so one-sided, with a terminating resistor. Already a one-sided termination resistor can namely cause a sufficiently rapid decay of the interference signals.

Eine besonders vorteilhafte Variante dieser Ausgestaltung ergibt sich dadurch, dass der einseitige Abschluss-Widerstand jeweils am Röntgenröhren-seitigen jeder Hochspannungs-Leitung angeordnet ist. Dadurch kann die für den Betrieb einzuhaltende hohe Ausgangsimpedanz des Röntgengenerators beibehalten werden.A particularly advantageous variant of this embodiment results from the fact that the one-sided terminating resistor is arranged in each case on the X-ray tube side of each high-voltage line. As a result, it is possible to maintain the high output impedance of the X-ray generator to be observed for operation.

Bei einer weiteren vorteilhaften Ausgestaltung der Erfindung wird die Impedanz der Abschluss-Widerstände an die Leitungsimpedanz der jeweiligen Leitung angepasst. Eine ausreichende Dämpfung ergibt sich insbesondere, wenn die Impedanz der Abschluss-Widerstände der Impedanz der Hochspannungs-Leitungen entspricht.In a further advantageous embodiment of the invention, the impedance of the terminating resistors is adapted to the line impedance of the respective line. Adequate damping is obtained in particular if the impedance of the terminating resistors corresponds to the impedance of the high-voltage lines.

Weitere Ausgestaltungen der Erfindung sind Gegenstand der abhängigen Patentansprüche.Further embodiments of the invention are the subject of the dependent claims.

Nachfolgend werden Ausführungsbeispiele der Erfindung anhand von Figuren näher beschrieben. Die Figuren zeigen:

FIG 1
den prinzipiellen Aufbau des Hochspannungskreises einer Röntgeneinrichtung gemäß Stand der Technik,
FIG 2
Spannungsverhältnisse in der Hochspannungs-Versor- gung während des Betriebs der Röntgeneinrichtung,
FIG 3
Spannungsverhältnisse in der Hochspannungs-Versor- gung unmittelbar nach Auftreten eines Kurzschlusses in der Röntgenröhre,
FIG 4
Hochspannungs-Leitung mit parallelen Abschluss- Widerständen,
FIG 5
Hochspannungs-Leitung mit seriellen Abschluss- Widerständen,
FIG 6
Hochspannungskreis einer Röntgeneinrichtung mit Ab- schluss-Widerständen gemäß der Erfindung mit Filterinduktivitäten für Kathodenheizstrom,
FIG 7
Hochspannungskreis einer Röntgeneinrichtung mit in die Röntgen- röhre integriertem Heizstromtransformator,
FIG 8
Hochspannungskreis einer Röntgeneinrichtung mit Hochspannungs- Glättungs-Kapazitäten an den Ausgängen des Röntgen- generators,
FIG 9
simulierter Spannungsverlauf an der Kathode einer Röntgeneinrichtung gemäß Stand der Technik,
FIG 10
simulierter Spannungsverlauf an der Kathode einer Röntgeneinrichtung gemäß der Erfindung.
Embodiments of the invention will be described in more detail with reference to figures. The figures show:
FIG. 1
the basic structure of the high voltage circuit of an X-ray device according to the prior art,
FIG. 2
Voltage conditions in the high-voltage supply during the operation of the X-ray device,
FIG. 3
Voltage conditions in the high-voltage supply immediately after the occurrence of a short circuit in the X-ray tube,
FIG. 4
High-voltage cable with parallel termination resistors,
FIG. 5
High-voltage cable with serial termination resistors,
FIG. 6
High-voltage circuit of an X-ray device with termination resistors according to the invention with filter inductances for cathode heating current,
FIG. 7
High-voltage circuit of an X-ray device with a heating current transformer integrated in the X-ray tube,
FIG. 8
High-voltage circuit of an X-ray device with high-voltage smoothing capacitances at the outputs of the X-ray generator,
FIG. 9
simulated voltage curve at the cathode of an X-ray device according to the prior art,
FIG. 10
simulated voltage curve at the cathode of an X-ray device according to the invention.

In Figur 1 ist der prinzipielle Aufbau des Hochspannungskreises einer Röntgeneinrichtung gemäß Stand der Technik dargestellt. Innerhalb des Röntgengenerators 1 erzeugt ein Primärspannungsgenerator 3 eine Primärspannung, die an Hochspannungs-Transformatoren 5 weitergeleitet und von diesen in eine für den Betrieb der Röntgenröhre ausreichende Hochspannung transformiert wird. Die von den Hochspannungs-Transformatoren 5 abgegebene Hochspannung wird an die Bauelemente 7, in denen eine Gleichrichter-Diode und eine Glättungs-Kapazität angedeutet sind, weitergeleitet und von diesen gleichgerichtet und geglättet. Die Bauelemente 7 geben die Hochspannung an die Dämpfungs-Widerstände 9 (RD) ab. Die Dämpfungs-Widerstände 9 (RD) haben die Aufgabe, den Röntgengenerator 1 weitgehend vor Überspannungen und Störsignalen aus der Hochspannungs-Versorgung zu schützen. Sie weisen normalerweise Werte in der Größenordnung einiger Kilo-Ohm auf.In FIG. 1 shows the basic structure of the high voltage circuit of an X-ray device according to the prior art. Within the X-ray generator 1, a primary voltage generator 3 generates a primary voltage, which is forwarded to high-voltage transformers 5 and transformed by them into a high voltage which is sufficient for the operation of the X-ray tube. The high voltage supplied by the high-voltage transformers 5 is forwarded to the components 7, in which a rectifier diode and a smoothing capacitor are indicated, rectified and smoothed by these. The components 7 deliver the high voltage to the damping resistors 9 (R D ). The damping resistors 9 (RD) have to protect the X-ray generator 1 largely from surges and interference signals from the high voltage supply the task. They usually have values on the order of a few kilo-ohms.

An den Röntgengenerator 1 ist durch eine dazwischen liegende Hochspannungs-Versorgung die Röntgen-Röhre 15 angeschlossen, wobei die Hochspannungs-Versorgung im wesentlichen aus einer anodischen koaxialen Hochspannungs-Leitung 11 und einer kathodische koaxialen Hochspannungs-Leitung 13 besteht. Der koaxiale Aufbau der Hochspannungs-Leitungen 11 und 13 ist durch die zeichnerische Darstellung als Kasten anstelle als Linie angedeutet. Die anodische Hochspannungs-Leitung 11 verbindet den Ausgang des Röntgengenerators 1 mit der Anode 17 der Röntgenröhre 15. Analog verbindet die kathodische Hochspannungs-Leitung 13 die Kathode 19 der Röntgenröhre 15. Die Röntgenröhre 15 kann zweistrahlig, d.h. als Zweifokusröhre, ausgebildet sein, weswegen die Kathode 19 andeutungsweise mit zwei Wendeln dargestellt ist. Die beiden Wendeln der Kathode 19 werden durch den Heiztransformator 21 mit Heizstrom versorgt.The x-ray tube 15 is connected to the x-ray generator 1 through an intermediate high-voltage supply, the high-voltage supply consisting essentially of an anodic coaxial high-voltage line 11 and a cathodic coaxial high-voltage line 13. The coaxial structure of the high-voltage lines 11 and 13 is indicated by the graphic representation as a box instead of a line. The anodic high-voltage line 11 connects the output of the X-ray generator 1 with the anode 17 of X-ray tube 15. Analogously connects the cathodic high-voltage line 13, the cathode 19 of the X-ray tube 15. The X-ray tube 15 may be two-beam, ie, designed as a two-focus tube, so the cathode 19 is shown by way of hint with two coils. The two coils of the cathode 19 are supplied by the heating transformer 21 with heating current.

Um die Probleme zu verringern, die in Zusammenhang mit in der Röntgenröhre 15 auftretenden Kurzschlüssen verursacht werden, ist es bekannt, zum einen am Röntgengenerator 1 hochohmige Dämpfungs-Widerstände 9 (RD) im Kiloohm-Bereich vorzusehen, zum anderen in der gesamten Röntgeneinrichtung auf die saubere Erdung aller Komponenten zu achten, um eindeutige Bezugspotentiale zu gewährleisten und Induktionsschleifen zu vermeiden. Dadurch soll vor allem eine "Verschleppung" der Störpotentiale vermieden werden. Die saubere Erdung aller Komponenten ist durch die mehrfache Erdung 23 der koaxialen Hochspannungs-Leitungen dargestellt.In order to reduce the problems which are caused in connection with short circuits occurring in the x-ray tube 15, it is known, on the one hand, to provide high-impedance attenuation resistors 9 (R D ) in the kilo-ohm range on the x-ray generator 1 and, on the other hand, in the entire x-ray device Ensure the clean grounding of all components to ensure clear reference potential and avoid induction loops. This should be avoided especially a "carryover" of the interference potentials. The clean grounding of all components is represented by the multiple grounding 23 of the coaxial high voltage lines.

Figur 2 zeigt eine schematische Darstellung des Hochspannungskreises einer Röntgeneinrichtung gemäß Stand der Technik. Durch den Generator 31 wird die Röntgenspannung U0 erzeugt und über die Dämpfungs-Widerstände 9 (RD) an die Hochspannungs-Leitungen 11 und 13 abgegeben. Über die Hochspannungs-Leitungen 11 und 13 liegt die Spannung an der Röntgenröhre an, die hier als Lastwiderstand 33 (RL) eingezeichnet ist. Der Hochspannungskreis ist während des Betriebs dargestellt, d.h. in eingeschwungenem Zustand. Die anodische Hochspannungs-Leitung 11 liegt auf ihrer gesamten Länge auf Potential U0, die kathodische Hochspannungs-Leitung 13 liegt auf ihrer gesamten Länge auf -U0 Volt. Der Anschaulichkeit halber wird in Figur 3 und im folgenden lediglich die anodische Seite betrachtet und die kathodische außer Acht gelassen. Die Potenzialverteilung auf der anodischen Hochspannungs-Leitungen ist in Figur 2 durch Pfeile angedeutet, die mit plus, minus und U0 bezeichnet sind. Der Potentialabfall in den Dämpfungs-Widerständen 9 (RD) soll vernachlässigt werden. FIG. 2 shows a schematic representation of the high voltage circuit of an X-ray device according to the prior art. By the generator 31, the x-ray voltage U 0 is generated and delivered via the damping resistors 9 (R D ) to the high-voltage lines 11 and 13. About the high-voltage lines 11 and 13, the voltage is applied to the X-ray tube, which is shown here as a load resistor 33 (R L ). The high voltage circuit is shown during operation, ie in steady state. The anodic high-voltage line 11 is at its entire length at potential U 0 , the cathodic high-voltage line 13 is on its entire length to -U 0 volts. For the sake of clarity, in FIG. 3 and in the following only the anodic side and the cathodic disregarded. The potential distribution on the anodic high voltage lines is in FIG. 2 indicated by arrows labeled plus, minus and U 0 . The potential drop in the damping resistors 9 (R D ) should be neglected.

Figur 3 zeigt die gleiche schematische Darstellung des Hochspannungskreises gemäß Stand der Technik wie die vorhergehende Figur 2 mit den gleichen Bezugszeichen. Figur 3 zeigt den Hochspannungskreis jedoch zu einem anderen Zeitpunkt, nämlich unmittelbar nach Auftreten eines Kurzschlusses in der Röntgenröhre. FIG. 3 shows the same schematic representation of the high voltage circuit according to the prior art as the previous one FIG. 2 with the same reference numerals. FIG. 3 However, the high-voltage circuit at another time, namely immediately after the occurrence of a short circuit in the X-ray tube.

Das Auftreten eines Kurzschlusses in der Röntgenröhre ist damit gleichbedeutend, dass der Lastwiderstand 33 (RL) verschwindend gering wird, d.h. RL = 0. Das Verschwinden des Lastwiderstandes 33 (RL) hat zur Folge, dass die Spannung an den Hochspannungs-Leitungen 11 sowie 13 zusammenbricht, weil die Ladungen, die sich auf den Hochspannungleitungen 11 sowie 13 befinden, über den Kurzschluss in der Röntgenröhre abfließen können. Diese Art der Entladung einer gleichmäßig aufgeladenen Leitung ist ein Standardproblem, das in der Literatur bestens bekannt ist. Näherungsweise kann der Entladungsvorgang so beschrieben werden, dass die Hälfte der Ladungen auf der Leitung nach links läuft, die andere Hälfte der Ladungen nach rechts. Dadurch bewegen sich Wellen mit der halben Ausgangsspannung, also U0/2, auf jeder Leitung nach links und rechts voneinander weg. Dies ist in Figur 3 lediglich für die anodische Hochspannungs-Leitung 11 durch Pfeile angedeutet, die mit + und U0/2 bezeichnet sind, und die entlang der Hochspannungs-Leitung 11 nach rechts bzw. links gerichtet sind. Die Pfeile sollen das Abfließen der Ladungen symbolisieren.The occurrence of a short circuit in the X-ray tube is thus equivalent to the load resistor 33 (R L ) is vanishingly small, ie R L = 0. The disappearance of the load resistor 33 (R L ) has the consequence that the voltage on the high-voltage lines 11 and 13 collapses, because the charges located on the high voltage lines 11 and 13, can flow through the short circuit in the X-ray tube. This type of uniformly charged line discharge is a standard problem well known in the literature. As an approximation, the discharge process can be described as half of the charges on the line going to the left, the other half of the charges to the right. Characterized waves move at half the output voltage, ie U 0/2 on each line to the left and right away from one another. This is in FIG. 3 indicated only by the anodic high-voltage line 11 by arrows, which are denoted by + and U 0/2 , and which are directed along the high-voltage line 11 to the right or left. The arrows should symbolize the discharge of the charges.

In dem Hochspannungskreis treffen die auseinander laufenden Wellen sowohl links als auch rechts auf Impedanz-Sprungstellen. Links sind dies die Dämpfungs-Widerstände 9 (RD), rechts ist dies der Kurzschluss in der Röntgenröhre, also der Lastwiderstand 33 (RL), der den Wert RL = 0 angenommen hat. Die Sprungstellen in der Impedanz reflektieren die voneinander fortlaufenden Wellen, wobei ein Kurzschluss einen Reflexions-Faktor r = -1 bewirkt. An einem Kurzschluss reflektierte Wellen wechseln daher bekanntlich das Vorzeichen, vorliegend wechselt ihre Spannung also von +U0/2 auf -U0/2. Die reflektierten Wellen laufen anschließend wieder aufeinander zu, begegnen sich und laufen erneut auseinander, bis sie wieder an den Sprungstellen der Leitungsimpedanz reflektiert werden. Für die hin und herlaufenden Wellen ergibt sich eine von der Länge der Hochspannungs-Leitungen 11 bzw. 13 abhängige Schwingungsdauer. Nach einem Viertel dieser Schwingungsdauer nimmt die Hochspannungs-Leitung auf der gesamten Länge die Spannung 0 an, nach der Hälfte der Schwingungsdauer die Spannung -U0 und nach drei Vierteln der Schwingungsdauer wiederum die Spannung 0, bis sich der Schwingungsvorgang nach einer ganzen Schwingungsdauer zu wiederholen beginnt. Die Schwingung setzt sich grundsätzlich endlos fort, wird in der Realität aber durch Leitungsverluste gedämpft.In the high voltage circuit, the diverging waves hit impedance jumps both left and right. On the left these are the damping resistors 9 (R D ), on the right this is the short circuit in the X-ray tube, ie the load resistor 33 (R L ), which has assumed the value R L = 0. The jumps in the impedance reflect the consecutive waves, with a short circuit causing a reflection factor r = -1. Therefore known to change the sign on a short reflected waves, in this case changes its voltage so of + U 0/2 0 -U / 2. The reflected waves then converge, encounter each other, and diverge again until they are reflected back to the discontinuity of the line impedance. For the reciprocating waves results in a dependent on the length of the high-voltage lines 11 and 13 period of oscillation. After a quarter of this oscillation period, the high-voltage line assumes the voltage 0 over the entire length, the voltage -U 0 after half of the oscillation period and again the voltage 0 after three quarters of the oscillation period, until the oscillation process is repeated after a complete oscillation period begin. The oscillation continues basically endlessly, but is dampened in reality by line losses.

Der Vereinfachung halber wurde der Vorgang nur für die anodische Hochspannungs-Leitung 11 beschrieben, die Vorgänge auf der kathodischen Hochspannungs-Leitung 13 verlaufen grundsätzlich analog dazu mit umgekehrtem Vorzeichen.For the sake of simplicity, the process has been described only for the anodic high-voltage line 11, the processes on the cathodic high-voltage line 13 are basically analogous to this with the opposite sign.

Im Ergebnis wird auf den Hochspannungs-Leitungen 11 und 13 eine Schwingung erhalten, bei der auf der jeweiligen Leitung selbst zwar keine Überspannungen auftreten, die aber wechselnd die Spannungen +U0 und -U0 annimmt. Daher tritt an den Dämpfungs-Widerständen 9 (RD) im Verlauf der Schwingung die doppelte Spannung auf, also 2U0. Bei einer Länge der Hochspannungs-Leitungen von beispielsweise 12 Metern ergibt sich eine Schwingungsdauer von 266 Nano-sekunden, also eine Frequenz in der Größenordnung von einigen Mega-Hertz. Diese Schwingung, die als Störsignal aufzufassen ist, und die dabei auftretenden Überspannungen, können Bauteilausfälle und Betriebsstörungen in der Röntgeneinrichtung bewirken.As a result, an oscillation is obtained on the high-voltage lines 11 and 13, in which no overvoltages occur on the respective line itself, but alternately assumes the voltages + U 0 and -U 0 . Therefore, at the attenuation resistors 9 (R D ) occurs in the course of the vibration, the double voltage, ie 2U 0 . With a length of the high-voltage lines of, for example, 12 meters results in a period of oscillation of 266 nanoseconds, ie a frequency in the order of a few megahertz. This vibration, which is to be regarded as an interference signal, and the overvoltages occurring in the process, can cause component failures and malfunctions in the X-ray device.

Figur 4 zeigt die anodische Seite eines Hochspannungskreises einer Röntgeneinrichtung mit Gleichrichtungs- und Dämpfungsbauelement 7, Dämpfungs-Widerstand 9 (RD) , über die Erdungen 23 geerdeten koaxialen Hochspannungs-Leitung 11 und Röntgenröhre 15. Dieser herkömmliche Aufbau ist ergänzt durch den Abschluss-Widerstand 37 (RA), der das Röntgengenerator-seitige Ende der Hochspannungs-Leitung 11 abschließt, und durch den Abschluss-Widerstand 38 (RA), der das Röntgenröhren-seitige Ende der Hochspannungs-Leitung 11 abschließt. Die Abschluss-Widerstände 37, 38 (RA) sind parallelgeschaltet, sie liegen also zwischen dem jeweiligen Ende der Hochspannungs-Leitung 11 und der Erdung 23. Sie können durch Löten verbunden werden. Für die Leitungsimpedanz der Hochspannungs-Leitungen 11, 13 im Hochspannungskreis einer Röntgeneinrichtung sind Werte von etwa 40 bis 50 Ohm üblich. Die Abschluss-Widerstände 39 (RA) weisen daher einen Wert von etwa 45 Ohm auf, da ihre Dämpfungswirkung optimal wird, wenn ihre Impedanz derjenigen der Hochspannungs-Leitungen 11, 13 entspricht. FIG. 4 1 shows the anodic side of a high voltage circuit of an X-ray device with rectification and attenuation device 7, attenuation resistor 9 (R D ), grounded coaxial high voltage line 11, and X-ray tube 15. This conventional construction is supplemented by termination resistor 37 (FIG. R A ) terminating the X-ray generator side end of the high voltage line 11, and the termination resistor 38 (R A ) terminating the X-ray tube side end of the high voltage line 11. The termination resistors 37, 38 (R A ) are connected in parallel, so they lie between the respective end of the high voltage line 11 and the ground 23. They can be connected by soldering. For the line impedance of the high-voltage lines 11, 13 in the high voltage circuit of an X-ray device values of about 40 to 50 ohms are common. The termination resistors 39 (R A ) therefore have a value of about 45 ohms, since their damping effect becomes optimal when their impedance corresponds to that of the high voltage lines 11, 13.

Der Abschluss alleine mit parallelen Abschluss-Widerständen 37, 38 (RA) wäre in der Realität jedoch nicht anwendbar, da im Betriebszustand an den beiden Abschluss-Widerständen 37 (RA) und 38 (RA) die gesamte Betriebsspannung anstünde und zur Masse hin abfiele, was zu dauerhaften und extrem hohen Leistungsverlusten führen würde. Außerdem wäre der Röntgenröhren-seitige Abschluss-Widerstand 38 (RA) durch den Kurzschluss in der Röntgenröhre 15 kurzgeschlossen und würde damit keine Dämpfungswirkung aufbauen können.The conclusion alone with parallel terminating resistors 37, 38 (R A ) would not be applicable in reality, since in the operating state at the two terminating resistors 37 (R A ) and 38 (R A ), the entire operating voltage would be present and to ground fall off, which would lead to permanent and extremely high power losses. In addition, the X-ray tube end termination resistor 38 (R A ) would be shorted by the short in the X-ray tube 15 and would not be able to build up a damping effect.

Daher sind in Ergänzung zu den Abschluss-Widerstände 37, 38 (RA) Hochspannungs-Glättungs-Kapazitäten 41 (CH) vorgesehen, die zwischen diesen und der Erdung 23 in Serie geschaltet sind. Die Hochspannungs-Glättungs-Kapazitäten 41 (CH) haben die Aufgabe, hochfrequente Störsignale und Überspannungen zur Erdung 23 passieren zu lassen, niederfrequente und Gleichspannungs-Nutzsignale jedoch zu blockieren. Sie dienen also als Hochpass, dessen Frequenz so zu wählen ist, dass Störsignale zur Erdung abfließen können, in Bezug auf Nutzsignale jedoch keine Verlustleistung auftritt. Die Hochspannungs-Glättungs-Kapazitäten 41 (CH) verhindern außerdem, dass der Röntgenröhren-seitige Abschluss-Widerstand 38 (RA) durch den Kurzschluss in der Röntgenröhre 15 kurzgeschlossen wird und deshalb wirkungslos bleibt. Wegen der hohen Frequenzen der Störsignale wird ein Hochpass mit relativ hoher Grenzfrequenz benötigt, daher wird als Kapazität der Hochspannungs-Glättungs-Kapazitäten 41 (CH) ein Wert in der Größenordnung von etwa 50 Nano-Farad gewählt. Es können z.B. Keramik- oder Folien-Kondensatoren verwendet werden, die durch Löten verbunden werden können.Therefore, in addition to the termination resistors 37, 38 (R A ), there are provided high-voltage smoothing capacitances 41 (C H ) connected in series between them and the ground 23. The purpose of the high-voltage smoothing capacitances 41 (C H ) is to allow high-frequency interference signals and overvoltages to pass to ground 23, but to block low-frequency and DC useful signals. They serve that is, as a high-pass filter whose frequency is to be selected such that interference signals can flow away to the ground, but no power loss occurs with respect to useful signals. The high voltage smoothing capacitances 41 (C H ) also prevent the X-ray tube end termination resistor 38 (R A ) from being shorted by the short circuit in the X-ray tube 15 and therefore remain ineffective. Because of the high frequencies of the interfering signals, a high pass with a relatively high cut-off frequency is needed, therefore, than the high-voltage smoothing capacitor 41 capacitances (C H) is a value in the order of about 50 nano-Farads is selected. For example, ceramic or foil capacitors can be used, which can be connected by soldering.

Figur 5 zeigt eine Variante der Schaltung in Abkehr von der Parallelschaltung der Abschluss-Widerstände. Dargestellt ist das Gleichrichter- und Dämpfungsbauelement 7, die koaxiale Hochspannungs-Leitung 11 samt Erdungen 23 sowie die Röntgenröhre 15. Außerdem dargestellt sind die Abschluss-Widerstände 39 (RA), diesmal jedoch in serieller Schaltung zwischen der Hochspannungs-Leitung 11 und dem Bauelement 7 sowie zwischen der Hochspannungs-Leitung 11 und der Röntgenröhre 15. Der Röntgengenerator-seitige niederohmige Abschluss-Widerstand 39 (RA) ersetzt dabei den normalerweise vorzusehenden hochohmigen Dämpfungs-Widerstand RD, der das Bauelement 7 sowie den sich dahinter anschließenden sonstigen, in der Figur 5 nicht dargestellten, Röntgengenerator vor Überspannungen schützt. FIG. 5 shows a variant of the circuit in departure from the parallel connection of the terminating resistors. Shown is the rectifier and attenuation component 7, the coaxial high-voltage line 11 including grounding 23 and the X-ray tube 15. Also shown are the terminating resistors 39 (R A ), but this time in series between the high-voltage line 11 and the device 7 and between the high-voltage line 11 and the X-ray tube 15. The X-ray generator-side low-impedance termination resistor 39 (R A ) replaces the normally provided high-impedance damping resistor R D , the component 7 and the other subsequent, in of the FIG. 5 not shown, X-ray generator protects against overvoltages.

Da der normalerweise vorzusehende Dämpfungs-Widerstand RD in der Größenordnung mehrerer Kilo-Ohm liegt, bietet der Abschluss-Widerstand 39 (RA), der in der Größenordnung von einigen Zehn Ohm liegt, nicht den selben Schutz vor Überspannungen im Röntgengenerator 1. Der Röntgengenerator 1 müsste also ausreichend robust dimensioniert sein, um im Falle eines Kurzschlusses in der Röntgenröhre 15 Ströme im Kilo-Ampere-Bereich zu überstehen.Since the normally-to-be-provided damping resistor R D is on the order of several kilo-ohms, the termination resistor 39 (R A ), which is on the order of tens of ohms, does not offer the same protection against overvoltages in the x-ray generator 1 X-ray generator 1 would therefore have to be sufficiently robust to withstand 15 currents in the kilo-ampere range in the event of a short circuit in the X-ray tube.

In einer abgeänderten Variante der Schaltung in Figur 5 weisen die Abschluss-Widerstände 39 (RA) nicht die gleiche Impedanz wie die abzuschließenden Hochspannungs-Leitungen 11, 13 auf, sondern die doppelte Impedanz oder mehr, also mindestens 90 Ohm. Durch diese Dimensionierung wird eine weitgehend aperiodische Entladung der Hochspannungs-Leitungen 11, 13 bewirkt. Die aperiodische Entladung geht stufenweise vor sich und erfordert längere Zeit als die Entladung durch Abschluss-Widerstände 39 (RA) mit der optimalen Impedanz von 45 Ohm. Die höhere Dimensionierung der Abschluss-Widerstände 39 (RA) hat jedoch den Vorteil, dass der Röntgenröhren-seitige Kurzschluss-Strom stärker begrenzt wird. Ein Nachteil besteht in der höheren Dauerverlustleitung, wie durch den Abfall der Hochspannung über den Abschluss-Widerständen 39 (RA) verursacht wird. Außerdem ist beim Betrieb einer so ausgerüsteten Röntgeneinrichtung zu beachten, dass die Röntgengeneratorseitig gemessene Röntgenröhrenspannung um den erhöhten Spannungsabfall verkehrt gemessen wird. Dies kann aber durch eine rechnerische Korrektur des Messwertes kompensiert werden.In a modified variant of the circuit in FIG. 5 the terminating resistors 39 (R A ) do not have the same impedance as the high-voltage lines 11, 13 to be terminated, but the double impedance or more, ie at least 90 ohms. By this dimensioning a largely aperiodic discharge of the high-voltage lines 11, 13 is effected. The aperiodic discharge progresses step by step and requires more time than the discharge through termination resistors 39 (R A ) with the optimum impedance of 45 ohms. However, the increased dimensions of the terminal resistors 39 (R A) has the advantage that the X-ray tube short-circuit current is limited more to advantage. A disadvantage is the higher sustained loss conduction, as caused by the drop in high voltage across the termination resistors 39 (R A ). In addition, when operating an X-ray device equipped in this way, it should be noted that the X-ray tube voltage measured on the X-ray generator side is measured upside down by the increased voltage drop. However, this can be compensated by a mathematical correction of the measured value.

Figur 6 zeigt einen unter den beschriebenen Aspekten verbesserten Hochspannungskreis gemäß der Erfindung. Bei diesem ist hinsichtlich der Abschluss-Widerstände insofern ein Kompromiss realisiert, als hier sowohl die anodische Hochspannungs-Leitung 11 als auch die kathodische Hochspannungs-Leitung 13 jeweils nur auf einer Seite durch einen Abschluss-Widerstand 39 (RA) abgeschlossen sind. Die Impedanz der Abschluss-Widerstände 39 (RA) ist ungefähr gleich groß wie die Leitungsimpedanz der Hochspannunges-Leitungen 11 und 13, also ungefähr 45 Ω. Die Figur 6 zeigt den Röntgengenerator 1, darin befindlich den Primärspannungs-Erzeuger 3, die Hochspannungs-Transformatoren 5, die Gleichrichter- und Dämpfungsbauelemente 7, die Dämpfungs-Widerstände 9 (RD) sowie den Heizstromtransformator 21. Der Röntgengenerator 1 ist über die mit der Erdung 23 verbundenen koaxialen Hochspannungs-Leitungen 11 und 13 mit der Röntgenröhre 15 verbunden. FIG. 6 shows a high voltage circuit according to the invention improved under the aspects described. In this respect, a compromise is realized in terms of the terminating resistors, as here both the high-voltage anodic line 11 and the cathodic high-voltage line 13 are terminated only on one side by a terminating resistor 39 (R A ). The impedance of the terminating resistors 39 (R A ) is approximately equal to the line impedance of the high voltage lines 11 and 13, that is about 45 Ω. The FIG. 6 shows the X-ray generator 1, therein the primary voltage generator 3, the high-voltage transformers 5, the rectifier and damping components 7, the damping resistors 9 (R D ) and the heating current transformer 21. The X-ray generator 1 is connected to the ground 23rd connected coaxial high-voltage lines 11 and 13 connected to the X-ray tube 15.

Die Abschluss-Widerstände 39 (RA) sind zwischen den Hochspannungs-Leitungen 11 und 13 und der Röntgenröhre 15 in Serienschaltung angeordnet. Der lediglich einseitige Abschluss der Hochspannungs-Leitungen 11 und 13 verhindert das Entstehen einer dauerhaften Schwingung bei Auftreten eines Kurzschlusses in der Röntgenröhre 15.The termination resistors 39 (R A ) are connected in series between the high voltage lines 11 and 13 and the X-ray tube 15. The only one-sided completion of the high-voltage lines 11 and 13 prevents the occurrence of a permanent vibration in the event of a short circuit in the X-ray tube 15th

Von den beiden zum Ladungsausgleich in den Hochspannungs-Leitungen 11 und 13 auseinanderlaufenden Wellen mit der Spannung +U0/2 bzw. -U0/2 wird lediglich die jeweils in Richtung Röntgengenerator 1 laufende refklektiert, da lediglich generatorseitig ein Impedanz-Sprung auftritt. In der mit Abschluss-Widerständen 39 (RA) ausgestatteten Richtung zur Röntgenröhre 15 laufen die Wellen ohne reflektiert zu werden weiter und die Ladungen können abfließen. Daher endet der Vorgang des Ladungsausgleiches nach einmaliger Reflexion. Der lediglich einseitige Abschluss der Hochspannungs-Leitungen 11 und 13 bietet so ein ausreichend schnelles Abklingen der Störsignale und damit eine ausrechende Dämpfung von Überspannungen.Of the two, to balance the charge in the high voltage lines 11 and 13 diverging waves only the current respectively in the direction of the X-ray generator 1 to the voltage + U 0/2 or -U 0/2 is refklektiert, since only the generator side an impedance jump occurs. In the direction equipped with terminating resistors 39 (R A ) to the X-ray tube 15, the waves continue to be reflected without reflection and the charges can drain off. Therefore, the process of charge compensation ends after one-time reflection. The only one-sided completion of the high-voltage lines 11 and 13 thus provides a sufficiently rapid decay of the interference signals and thus a sufficient damping of overvoltages.

Auf der kathodischen Hochspannungsseite tritt die Besonderheit auf, dass der Kathode nicht nur der negative Teil der Röntgenröhrenspannung zugeführt wird, sondern zusätzlich auch der Heizstrom für die Kathode. Bei einer üblichen Zweifokusröhre sind also insgesamt drei Leitungen vorhanden, die die beiden Kathodenwendeln mit Heizstrom und der kathodischen Röntgenspannung versorgen. Würde in die Heizstrom-Versorgung ebenfalls ein Abschluss-Widerstand eingefügt werden, so würden unvertretbar hohe Verluste beim Heizstrom - der immerhin einige Ampere beträgt - verursacht werden. Da die drei Abschluss-Widerstände auf den Leitungen parallel zueinander geschaltet wären, müssten sie zudem einen dreimal größeren Widerstandswert als der einfache Abschluss-Widerstand 39 (RA) aufweisen, weswegen sich die Heizstrom-Verluste sogar noch verdreifachen würden.On the cathodic high voltage side, the peculiarity arises that the cathode is supplied not only the negative part of the X-ray tube voltage, but also the heating current for the cathode. In a conventional two-focus tube so a total of three lines are available, which supply the two cathode coils with heating current and the cathodic X-ray. If a terminating resistor were also inserted in the heating current supply, unacceptably high losses in the heating current - which would amount to a few amperes after all - would be caused. Moreover, since the three termination resistors on the lines would be connected in parallel, they would have to have a resistance value three times greater than the single termination resistor 39 (R A ), which would even triple the heating current losses.

Um trotzdem den Heizstrom-Transformator 21 im Falle eines Kurzschlusses in der Röntgenröhre 15 vor Überspannungen und Störsignalen zu schützen, werden deswegen anstelle von Abschluss-Widerständen zusätzliche Filter-Induktivitäten 40 eingeführt. Diese zusätzlichen Filter-Induktivitäten 40 werden als stromkompensierte Drosseln ausgeführt und in aller Regel durch Löten verbunden. Sie haben die Aufgabe, die hochfrequenten Störsignale in der Hochspannungs-Leitung 13 zu blockieren, den niederfrequenten Heizstrom hingegen passieren zu lassen. Insofern stellen sie eine Tiefpassfilterung dar. Zu diesem Zweck sind sie in serieller Schaltung zwischen der Röntgenröhre 15 und der Hochspannungsleitung 13 sowie dem Heizstrom-Transformator 21 angeordnet und in paralleler Schaltung zu dem Abschluss-Widerstand 39 (RA). Die Größe der Filter-Induktivitäten 40 ist abhängig von den Störsignalen in der Hochspannungs-Leitung 13 bzw. 11 zu bemessen. Da die Störsignale sich im Mega-Hertz-Bereich bewegen, der Heizstrom üblicherweise im Kilo-Hertz-Bereich, sind die Filter-Induktivitäten 40 mit einer Größe von etwa 50 Mikro-Henry zu bemessen.Nevertheless, in order to protect the heating current transformer 21 from overvoltages and interference signals in the event of a short circuit in the x-ray tube 15, additional filter inductors 40 are introduced instead of terminating resistors. These additional filter inductors 40 are designed as current-compensated chokes and usually connected by soldering. They have the task of blocking the high-frequency interference signals in the high-voltage line 13, however, to allow the low-frequency heating current to happen. As such, they provide low-pass filtering. For this purpose, they are arranged in series between the x-ray tube 15 and the high voltage line 13 and the heating current transformer 21 and in parallel with the terminating resistor 39 (R A ). The size of the filter inductors 40 is to be sized depending on the noise in the high voltage line 13 and 11 respectively. Since the spurious signals move in the megahertz range, the heating current usually in the kilohertz range, the filter inductors 40 are sized with a size of about 50 micro-Henry.

In einer verbesserten Ausführungsform dieser Schaltung wäre es möglich, die Filter-Induktivitäten 40 auf der kathodischen Hochspannungsseite als stromkompensierte Drossel auszuführen, um so die Gesamtinduktivität gegenüber dem Heizstrom nochmals zu reduzieren, ohne die Filter-Wirksamkeit gegenüber den hochfrequenten Störungssignalen zu verringern.In an improved embodiment of this circuit, it would be possible to perform the filter inductances 40 on the high-side cathodic side as a current-compensated inductor so as to further reduce the total inductance to the heating current without reducing the filter efficiency against the high-frequency disturbance signals.

Figur 7 zeigt eine weitere Variante, die bezüglich der Versorgung der Kathode mit Heizstrom wesentlich geändert ist. Figur 7 zeigt den Hochspannungskreis mit dem Röntgengenerator 1 und den bereits aus den vorhergehenden Figuren bekannten internen Baugruppen. An den Röntgengenerator 1 sind die anodische Hochspannungs-Leitung 11 und die kathodische Hochspannungs-Leitung 13 angeschlossen, diese wiederum sind mit den Abschluss-Widerständen 39 (RA) in Serienschaltung verbunden. Bei dem bisher gezeigten, herkömmlichen Aufbau der Röntgeneinrichtung ist der Heizstrom-Transformator 21 in der Peripherie der Röntgenröhre 15 angeordnet, etwa im Röntgengenerator 1 oder innerhalb des Hochspannungstanks, der die Röntgenröhre 15 zum Schutz der Umgebung vor Hochspannung und Strahlung umgibt. Im Gegensatz zu diesem herkömmlichen Aufbau ist der Heizstrom-Transformator 21 in Figur 7 innerhalb der Röntgenröhre 15 angeordnet. Dadurch ist der Heizstrom-Transformator 21 von den Störungsvorgängen in der Hochspannungs-Leitung 13 von vorne herein entkoppelt. Es müssen daher keine zusätzlichen Filter-Induktivitäten zur Filterung von Überspannungen oder Störsignalen vor der Heizstrom-versorgung angeordnet werden. FIG. 7 shows a further variant, which is substantially changed with respect to the supply of the cathode with heating current. FIG. 7 shows the high voltage circuit with the X-ray generator 1 and the already known from the previous figures internal assemblies. To the X-ray generator 1, the anodic high-voltage line 11 and the cathodic high-voltage line 13 are connected, these in turn are connected in series with the terminating resistors 39 (R A ). In the conventional design shown so far the X-ray device, the heating current transformer 21 is disposed in the periphery of the X-ray tube 15, such as in the X-ray generator 1 or within the high-voltage tank surrounding the X-ray tube 15 to protect the environment from high voltage and radiation. In contrast to this conventional structure, the heating current transformer 21 is in FIG. 7 disposed within the x-ray tube 15. Thereby, the heating current transformer 21 is decoupled from the disturbances in the high voltage line 13 from the outset. There is therefore no need to arrange additional filter inductors for filtering overvoltages or noise before the heating power supply.

Es ist offensichtlich, dass diese Variante der Erfindung eine Änderung im Aufbau der gesamten Röntgeneinrichtung erforderlich macht. Dagegen können Änderungen wie das Ergänzen von Abschluss-Widerständen und zusätzlichen Filter-Induktivitäten mit deutlich geringerem Aufwand durchgeführt werden.It is obvious that this variant of the invention requires a change in the structure of the entire X-ray device. In contrast, changes such as the addition of terminating resistors and additional filter inductors can be carried out with significantly less effort.

Figur 8 zeigt eine weitere Variante des Hochspannungskreises, bei der die Hochspannungs-Leitungen 11 und 13 ebenfalls jeweils einseitig mit Abschluss-Widerständen 39 (RA) versehen sind. Figur 8 zeigt den Röntgengenerator 1 mit den Dämpfungs-Widerständen 9 (RD) und ansonsten gleichen Bauelementen wie in den vorhergehenden Figuren. An den Röntgengenerator 1 sind sowohl auf der anodischen als auch auf der kathodischen Seite die Abschluss-Widerstände 39 (RA) angeschlossen, mit denen wiederum die koaxialen Hochspannungs-Leitungen 11 und 13 mit jeweiligen Erdungen 23 verbunden sind. Die Abschluss-Widerstände 39 (RA) sind seriell zwischen den Hochspannungs-Leitungen 11 und 13 und dem Röntgengenerator 1 geschaltet. Im Röntgengenerator 1 sind außerdem in üblicher Weise Dämpfungs-Widerstände 9 (RD) angeordnet, die-in der üblichen Größenordnung von einigen Kilo-Ohm bemessen sind. Die Abschluss-Widerstände 39 (RA) sind also zusätzlich zu den Dämpfungs-Widerständen 9 (RD) innerhalb des Röntgengenerators 1 vorgesehen. FIG. 8 shows a further variant of the high voltage circuit, in which the high-voltage lines 11 and 13 are also each provided on one side with terminating resistors 39 (R A ). FIG. 8 shows the X-ray generator 1 with the damping resistors 9 (R D ) and otherwise the same components as in the preceding figures. To the X-ray generator 1, both the anodic and on the cathodic side of the termination resistors 39 (R A ) are connected, with which in turn the coaxial high-voltage lines 11 and 13 are connected to respective groundings 23. The termination resistors 39 (R A ) are connected in series between the high voltage lines 11 and 13 and the X-ray generator 1. In the X-ray generator 1 further 9 (R D) are arranged in a conventional manner damping resistors which are dimensioned in-the usual order of a few kilo-ohms. The terminal resistors 39 (R A) are thus in addition to the damping resistors 9 (R D) provided inside the X-ray generator. 1

Zwischen den Abschluss-Widerständen 39 (RA) und den Dämpfungs-Widerständen 9 (RD) des Röntgengenerators 1 sind Hochspannungs-Glättungs-Kapazitäten 41 (CH) vorgesehen, in aller Regel Keramik- oder Folien-Kondensatoren, die durch Löten verbunden werden. Die Hochspannungs-Glättungs-Kapazitäten 41 (CH) sind mit dem jeweiligen Verbindungspunkt zwischen den Dämpfungs-Widerständen 9 (RD) und den Abschluss-Widerständen 39 (RA) sowie mit der jeweiligen Erdung 23 verbunden. Sie sind also parallel zu den Dämpfungs-Widerständen 9 (RD) und parallel zu den Abschluss-Widerständen 39 (RA) geschaltet.Between the termination resistors 39 (R A ) and the damping resistors 9 (R D ) of the X-ray generator 1 high-voltage smoothing capacitances 41 (C H ) are provided, usually ceramic or foil capacitors, which are connected by soldering become. The high-voltage smoothing capacitances 41 (C H ) are connected to the respective connection point between the snubber resistors 9 (R D ) and the termination resistors 39 (R A ) and to the respective ground 23. They are thus connected in parallel with the damping resistors 9 (R D ) and in parallel with the terminating resistors 39 (R A ).

Die Hochspannungs-Leitungen 11 und 13 sind bei dieser Variante der Schaltung mit der Serienschaltung der jeweiligen Abschluss-Widerstände 39 (RA) und den jeweiligen Hochspannungs-Glättungs-Kapazität 41 (CH) abgeschlossen. Damit näherungsweise nur der Ohm'sche Widerstand der Abschluss-Widerstände 39 (RA) zur Leitungsimpedanz beiträgt, müssen die Hochspannungs-Glättungs-Kapazitäten 41 (CH) groß genug gewählt sein, um bezüglich der Ausgleichsvorgänge in den Hochspannungs-Leitungen 11 und 13 niederohmig zu wirken. Mit dem für diesen Zweck erforderlichen Wert von etwa 50 Nano-Farad ist diese Variante der Schaltung insbesondere in Röntgeneinrichtungen von Interesse, in deren Hochspanungskreis von vorneherein eine große Hochspannungs-Glättungs-Kapazität vorgesehen ist.The high-voltage lines 11 and 13 are completed in this variant of the circuit with the series connection of the respective terminating resistors 39 (R A ) and the respective high-voltage smoothing capacitor 41 (C H ). For approximately only the ohmic resistance of the termination resistors 39 (R A ) to contribute to the line impedance, the high-voltage smoothing capacitances 41 (C H ) must be made large enough to be equalized in the high-voltage lines 11 and 13 to act low impedance. With the value of about 50 nanofarads required for this purpose, this variant of the circuit is of interest in particular in X-ray devices in whose high-voltage circuit a large high-voltage smoothing capacitance is provided from the outset.

Figur 9 zeigt eine Simulation des Spannungsverlaufs an der Kathode eines herkömmlichen Hochspannungskreises einer Röntgeneinrichtung, wie er in Figur 1 dargestellt ist. In Figur 9 ist die kathodische Hochspannung über der Zeit aufgetragen, wobei von einer Röntgen-typischen Hochspannung von 100 Kilo-Volt ausgegangen wird. Bei 50 Nano-Sekunden wird ein Kurzsschluss in der Röntgenröhre simuliert, der deutlich am Zusammenbrechen der kathodischen Spannung erkennbar ist. Der Kurzschluss setzt schlagartig ein und endet ebenso schlagartig bei 300 Nano-Sekunden. Dargestellt sind zwei Spannungsverläufe, von denen einer am Anfang der Hochspannungs-Leitung 13 abgegriffen ist, der andere am Ende der Hochspannungs-Leitung 13. Deutlich zu erkennen sind starke Störsignale, die sich nach Ende des Kurzschlusses über längere Zeit und mit deutlichen Überspanhungsspitzen fortsetzen. Während des Auftretens dieser Störungen wäre ein Betrieb der Röntgenröhre nicht sinnvoll möglich bzw. Bauteildefekte könnten auftreten. FIG. 9 shows a simulation of the voltage curve at the cathode of a conventional high voltage circuit of an X-ray device, as shown in FIG. 1 is shown. In FIG. 9 the cathodic high voltage is plotted over time, assuming an x-ray typical high voltage of 100 kilo-volts. At 50 nanoseconds, a short circuit in the X-ray tube is simulated, which is clearly visible at the collapse of the cathodic voltage. The short begins abruptly and ends abruptly at 300 nano-seconds. Shown are two voltage waveforms, one of which is at the beginning of the high voltage line 13 is tapped, the other at the end of the high-voltage line 13. Clearly visible are strong interference signals that continue after the end of the short circuit for a long time and with significant Überspanhungsspitzen. During the occurrence of these disturbances an operation of the X-ray tube would not be meaningfully possible or component defects could occur.

Figur 10 zeigt die gleiche Simulation bei Zugrundelegung einer Schaltung gemäß der Erfindung, wie er in Figur 6 dargestellt ist. Dargestellt ist wieder die kathodische Spannung über der Zeit. Die beiden Spannungsverläufe stellen wieder die Spannung am Anfang bzw. am Ende der Hochspannungs-Leitung 13 dar. Bei 50 ns setzt schlagartig ein Kurzschluss in der Röntgenröhre ein, der bei 300 ns ebenso schlagartig endet. Nach Ende des Kurzschlusses bleiben Überspannungen und Störsignale völlig aus. Stattdessen steigt die kathodische Spannung, gedämpft durch den Abschluss-Widerstand und die Filterinduktivitäten, nach und nach wieder an. Nach etwa 7 MikroSekunden, ein Zeitpunkt, der in Figur 10 nicht mehr dargestellt ist, erreicht die Kathode wieder die Betriebsspannung. FIG. 10 shows the same simulation on the basis of a circuit according to the invention as shown in FIG FIG. 6 is shown. Shown again is the cathodic voltage over time. The two voltage curves again represent the voltage at the beginning or at the end of the high-voltage line 13. At 50 ns abruptly sets in the X-ray tube, which ends just as abruptly at 300 ns. After the end of the short circuit, overvoltages and interfering signals are completely eliminated. Instead, the cathodic voltage, attenuated by the termination resistance and the filter inductances, gradually increases again. After about 7 microseconds, a time in FIG. 10 is no longer shown, the cathode reaches the operating voltage again.

Durch die Einführung von Abschluss-Widerständen und dazu parallel geschalteten Filter-Induktivitäten gelingt es also, die Röntgeneinrichtung vor Störungen und Beschädigungen durch die Folgen eines Kurzschlusses in der Röntgenröhre weitestgehend zu bewahren. Es muss lediglich eine geringe Zeit in Kauf genommen werden, bis nach Ende eines Kurzschlusses in der Röntgenröhre die Röntgenspannung wieder erreicht ist, so dass mit dem Betrieb der Röntgeneinrichtung fortgefahren werden kann.The introduction of terminating resistors and filter inductors connected in parallel thus makes it possible to largely protect the x-ray device from disturbances and damage due to the consequences of a short circuit in the x-ray tube. Only a small amount of time has to be accepted until the x-ray voltage has been reached again after the end of a short circuit in the x-ray tube, so that the operation of the x-ray device can be continued.

Claims (7)

  1. High-voltage supply (11, 13, 23) for an x-ray device comprising an x-ray tube (15) and an x-ray generator (1) for generation of the high voltage necessary for operating the x-ray tube (15), with the high voltage supply (11, 13, 23) having an electrically-conductive line (11, 13), for the connection of the x-ray generator (1) to the x-ray tube (15), with the line (11, 13) having one end at which it can be connected to the x-ray generator (1) and a further end at which it can be connected to the x-ray tube (15), with at least one end of the line (11, 13) being connected to an electrical terminal resistor (39) which is arranged between the line (11, 13) and the x-ray generator (1), or between the line (11, 13) and the x-ray tube (15), it being possible by means of the high voltage supply for a cathode (19) of the x-ray tube (15) to be connected to a transformer (21) for generation of heating current for the cathode (19), characterised in that
    a filter inductor (40), in particular in the order of 50 µH, is arranged in series in each electrical line for the connection of the heating current transformer (21) and the cathode (19), that a terminal resistor (39) is connected in series with the end of the line (13) which can be connected to the cathode (19) for the connection of the x-ray generator (1) and the cathode (15), that the heating current transformer (21) can also be connected to this line (13) and that each of the said filter inductors (40) is arranged in parallel with the terminal resistor (39).
  2. High-voltage supply (11, 13, 23) according to claim 1, characterized in that the terminal resistor and/or resistors (39) can be arranged in series between the line (11, 13) and the x-ray generator (1) or the x-ray tube (15).
  3. High-voltage supply (11, 13, 23) according to one of the preceding claims,
    characterised in that
    the impedance of the terminal resistor and/or resistors (39) is either equally as large or at least twice as large as the line impedance of the line (11, 13) connected thereto.
  4. High-voltage supply (11, 13, 23) according to one of the preceding claims,
    characterised in that
    just one terminal resistor (39) is connected in each instance to a line (11) for the connection of the x-ray generator (1) and an anode (17) of the x-ray tube (1) and to a line (13) for the connection of the x-ray generator.
  5. High-voltage supply (11, 13, 23) according to one of the preceding claims,
    characterised in that
    the said filter inductors (40) are embodied as common mode chokes.
  6. High-voltage supply (11, 13, 23) according to one of the preceding claims,
    characterised in that
    a terminal resistor (39) is connected to the end of a line (11, 13) which can be connected to the x-ray generator (1) for the connection of the x-ray generator (1) and the x-ray tube (15), and that with the connection between the x-ray generator (1) and the terminal resistor (39), a high-voltage smoothing capacitor (41) can be connected in series with the earth (23), in particular in the order of 50 nF.
  7. High-voltage supply (11, 13, 23) according to claim 1, 2, 3, 4, 5, 6 or 7,
    characterised in that
    the terminal resistors (39) are each connected to the ends of lines (11, 13) which can be connected to the x-ray tube (1) for connection of the x-ray generator (1) and the x-ray tube (15).
EP03785820A 2003-01-09 2003-12-15 High-voltage supply for an x-ray device Expired - Lifetime EP1584220B1 (en)

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DE10300542A DE10300542A1 (en) 2003-01-09 2003-01-09 High voltage supply for an X-ray device
DE10300542 2003-01-09
PCT/EP2003/014257 WO2004064458A2 (en) 2003-01-09 2003-12-15 High-voltage supply for an x-ray device

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AT (1) ATE483350T1 (en)
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DE102015213810B4 (en) * 2015-07-22 2021-11-25 Siemens Healthcare Gmbh High voltage feed for an X-ray tube
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DE50313141D1 (en) 2010-11-11
AU2003294854A1 (en) 2004-08-10
WO2004064458A2 (en) 2004-07-29
ES2352431T3 (en) 2011-02-18
WO2004064458A3 (en) 2004-09-16
US20060023841A1 (en) 2006-02-02
EP1584220A2 (en) 2005-10-12
US7110499B2 (en) 2006-09-19
ATE483350T1 (en) 2010-10-15
DE10300542A1 (en) 2004-07-22

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