Spark sources with electronic switching tubes

Claim 2

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, and means for supplying control signals between said control electrode and said cathode of said electronic switching tube, said signals being of such magnitude and polarity as to render said tube conductive so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap in precisely timed relationship to said control signals.

Claim 3

A spark source according to claim 1, in which said discharge circuit includes first and second inductive elements connected in series with said spark gap, and a shunting diode connected across the series combination of said second inductive element and said spark gap for modifying the waveform of the spark current.

Claim 4

A spark source according to claim 2, in which said shunting diode is reversely polarized relative to the polarization of said electronic switching tube whereby said shunting diode is reverse biased and nonconductive during the first half cycle of the capacitor discharge current.

Claim 5

A spark source according to claim 2, in which said shunting diode is polarized the same as said electronic switching tube and thereby is forward biased and conductive during the first half cycle of the capacitor discharge current.

Claim 6

A spark source according to claim 1, in which said discharge circuit includes first and second inductive elements connected in series with said spark gap, and a shunting diode circuit connected across the series combination of said second inductive element and said spark gap, said shunting diode circuit including a shunting diode and a third inductive element connected in series with said shunting diode.

Claim 7

A spark source according to claim 5, in which said shunting diode is polarized the same as said electronic switching tube and thus is forward biased and conductive during the first half cycle of the capacitor discharge current.

Claim 8

A spark source according to claim 5, in which said shunting diode is reversely polarized relative to the polarization of said electronic switching tube and thus is reverse biased and nonconductive during the first half cycle of the capacitor discharge current.

Claim 9

A spark source according to claim 5, in which said shunting diode is polarized the same as said electronic switching tube and thus is forward biased and conductive during the first half cycle of the capacitor discharge current, said third inductive element being adjustable for controlling the waveform of the spark current across said spark gap.

Claim 10

A spark source according to claim 5, in which said shunting diode is reversely polarized relative to the polarization of said electronic switching tube so that said diode is reverse biased and nonconductive during the first half cycle of the capacitor discharge current, said third inductive element being adjustable for controlling the waveform of the spark current across said spark bap.

Claim 11

A spark source according to claim 1, including diode rectifier means connected between the anode and cathode of said electronic switching tube, said diode rectifier means being polarized oppositely with respect to the polarization of said electronic switching tube.

Claim 12

A spark source according to claim 1, in which said electronic switching tube is of the gaseous type containing an ionizable gas or vapor.

Claim 13

A spark source according to claim 1, in which said electronic switching tube is of the gaseous type containing hydrogen.

Claim 14

A spark source, comprising a spark gap including first and second electrodes, a capacitor adapted to be discharged across said spark gap, power supply means for charging said capacitor; a charging circuit connected between said power supply means and said capacitor, and a discharge circuit connecting said spark gap across said capacitor, said discharge circuit including first and second inductive elements connected in series with said spark gap, and a shunting diode circuit connected in parallel with the series combination of said spark gap and said second inductive element, said shunting diode circuit including a shunting diode and a third inductive element in series with said shunting diode, said power supply means having a predetermined polarity to charge said capacitor with the same polarity, said shunting diode having a polarization corresponding to the polarization of said power supply means so that said diode is forward biased and conductive during the initial half cycle of the capacitor discharge current, said first electrode of said spark gap being grounded and being adapted to receive samples to be analyzed, said power supply means having positive and negative terminals and being polarized such that said positive terminal is connected through portions of said charging and discharging circuits to said grounded first electrode, said shunting diode and said second and third inductive elements being effective to polarize said grounded electrode as the anode during the first half cycle of the capacitor discharge current while polarizing said grounded electrode as the cathode during the remainder of the capacitor discharge current.

Claim 15

A spark source, comprising a spark gap including first and second electrodes, a capacitor adapted to be discharged across said spark gap, power supply means for charging said capacitor; a charging circuit connected between said power supply means and said capacitor, and a discharge circuit connecting said spark gap across said capacitor, said discharge circuit including first and second inductive elements connected in series with said spark gap, and a shunting diode circuit connected in parallel with the series combination of said spark gap and said second inductive element, said shunting diode circuit including a shunting diode and a third inductive element in series with said shunting diode, said power supply means having a predetermined polarity to charge said capacitor with the same polarity, said shunting diode having a polarization corresponding to the polarization of said power supply means so that said diode is forward biased and conductive during the initial half cycle of the capacitor discharge current, said first electrode of said spark gap being grounded and being adapted to receive samples to be analyzed, said power supply means having positive and negative terminals and being polarized such that said positive terminal is connected through portions of said charging and discharging circuits to said grounded first electrode, said shunting diode and said second and third inductive elements being effective to polarize said grounded electrode as the anode during the first half cycle of the capacitor discharge current while polarizing said grounded electrode as the cathode during the remainder of the capacitor discharge current.

Claim 16

A spark source according to claim 13, in which said third inductive element is adjustable for controlling the waveform of the spark current across said spark gap.

Claim 17

A spark source according to claim 14, in which said second inductive element is adjustable for controlling the waveform of the spark current across said spark gap.

Claim 18

A spark source, comprising a spark gap having a grounded electrode and an ungrounded electrode, a capacitor adapted to be discharged across said spark gap, said capacitor having positive and negative terminals adapted to be charged positively and negatively, a power supply for charging said capacitor, said power supply having positive and negative terminals connected to said positive and negative terminals of said capacitor, a discharge circuit connected between said capacitor and said spark gap, said discharge circuit including means for connecting said positive terminal of said capacitor to said grounded electrode of said spark gap, said discharge circuit including first and second inductive elements connected in series with said spark gap, and shunting diode means including a shunting diode and connected across the series combination of said spark gap and said second inductive element, said shunting diode being polarized the same as the polarization of said capacitor and thereby being forward biased and conductive during the first half cycle of the capacitor discharge current, whereby said shunting diode splits current away from said spark gap during said first half cycle.

Claim 19

A spark source, comprising a spark gap having a grounded electrode and an ungrounded electrode, a capacitor adapted to be discharged across said spark gap, said capacitor having positive and negative terminals adapted to be charged positively and negatively, a power supply for charging said capacitor, said power supply having positive and negative terminals connected to said positive and negative terminals of said capacitor, a discharge circuit connected between said capacitor and said spark gap, said discharge circuit including means for connecting said positive terminal of said capacitor to said grounded electrode of said spark gap, said discharge circuit including first and second inductive elements connected in series with said spark gap, and shunting diode means including a shunting diode and connected across the series combination of said spark gap and said second inductive element, said shunting diode being polarized the same as the polarization of said capacitor and thereby being forward biased and conductive during the first half cycle of the capacitor discharge current, whereby said shunting diode splits current away from said spark gap during said first half cycle.

Claim 20

A spark source according to claim 16, in which said second inductive element is adjustable for controlling the waveform of the spark current across said spark gap.

Claim 21

A spark source according to claim 16, in which said second inductive element has sufficient inductance to produce a uni-directional spark current after the first half cycle of the capacitor discharge current, said uni-directional spark current being polarized oppositely from the capacitor discharge current during the first half cycle.

Claim 22

A spark source according to claim 16, in which said diode has a sufficiently low impedance to prevent the break down of said spark gap during the first half cycle of the capacitor discharge current.

Claim 23

A spark source according to claim 19, in which said second inductive element has sufficient inductance to maintain a uni-directional space current after the initial half cycle of the capacitor discharge current.

Claim 24

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, and means for supplying positive control pulses between said control electrode and said cathode of said electronic switching tube, said pulses being of sufficient magnitude to trigger said tube into a conductive state so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap under the precise timing control of said pulses.

Claim 25

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, and means for supplying positive control pulses between said control electrode and said cathode of said electronic switching tube, said pulses being of sufficient magnitude to trigger said tube into a conductive state so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap under the precise timing control of said pulses.

Claim 26

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, and means for supplying positive control pulses between said control electrode and said cathode of said electronic switcing tube, said pulses being of sufficient magnitude to trigger said tube into a conductive state so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap under the precise timing control of said pulses, and a shunting impedance connected in shunting relationship to said spark gap and of a sufficiently low impedance value to prevent premature breakdown of said spark gap during the charging cycle of said capacitor due to coupling of a portion of charging voltage across said spark gap through distributed capacitance between said positive terminal of said capacitor and ground.

Claim 27

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, and means for supplying positive control pulses between said control electrode and said cathode of said electronic switcing tube, said pulses being of sufficient magnitude to trigger said tube into a conductive state so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap under the precise timing control of said pulses, and a shunting impedance connected in shunting relationship to said spark gap and of a sufficiently low impedance value to prevent premature breakdown of said spark gap during the charging cycle of said capacitor due to coupling of a portion of charging voltage across said spark gap through distributed capacitance between said positive terminal of said capacitor and ground.

Claim 28

A spark source according to claim 22, in which said shunting impedance is in the form of resistance means.

Claim 29

A spark source according to claim 23, in which said resistance means has a resistance value on the order of 10,000 to 100,000 ohms.

Claim 30

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, means for supplying positive control pulses between said control electrode and said cathode of said electronic switching tube, said pulses being of sufficient magnitude to trigger said tube into a conductive state so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap under the precise timing control of said pulses, a shunting diode connected in shunting relation to said spark gap, said shunting diode having a polarization which is opposite to that of said capacitor so that said shunting diode is back biased and nonconductive during the charging cycle of said capacitor, and a shunting impedance connected in shunting relation to said spark gap and having a sufficiently low impedance to prevent premature breakdown of said spark gap during the charging cycle of said capacitor due to the portion of the charging voltage which is coupled across said spark gap through the distributed capacitance between said positive terminal of said capacitor and said grounded electrode of said spark gap.

Claim 31

A spark source, comprising a spark gap including a grounded electrode and an ungrounded electrode, a capacitor having positive and negative terminals adapted to be positively and negatively charged, a power supply for charging said capacitor and having positive and negative terminals, means connecting said positive and negative terminals of said power supply to said positive and negative terminals of said capacitor, a discharge circuit connected between said negative terminal of said capacitor and said ungrounded electrode of said spark gap, an electronic switching tube having an anode, a thermionic cathode and a control electrode, means connecting said anode to said positive terminal of said capacitor, means connecting said cathode to said grounded electrode of said spark gap, a heating circuit for supplying heating power to said thermionic cathode, means for supplying positive control pulses between said control electrode and said cathode of said electronic switching tube, said pulses being of sufficient magnitude to trigger said tube into a conductive state so as to cause the discharge of said capacitor across said spark gap, sparks thereby being produced across said gap under the precise timing control of said pulses, a shunting diode connected in shunting relation to said spark gap, said shunting diode having a polarization which is opposite to that of said capacitor so that said shunting diode is back biased and nonconductive during the charging cycle of said capacitor, and a shunting impedance connected in shunting relation to said spark gap and having a sufficiently low impedance to prevent premature breakdown of said spark gap during the charging cycle of said capacitor due to the portion of the charging voltage which is coupled across said spark gap through the distributed capacitance between said positive terminal of said capacitor and said grounded electrode of said spark gap.

Claim 32

A spark source according to claim 25, in which said shunting impedance is in the form of resistor means.

Claim 33

A spark source according to claim 26, in which said resistor means has a resistance on the order of 10,000 to 100,000 ohms.