Energy-saving electronic strobe flash apparatus having dual flashtubes

Claim 2

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, means for charging said first capacitor, a first circuit comprising said first flashtube and said first and second capacitors, and having (1) a first state, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube and to charge said second capacitor, and (2) a second state, occurring in response to charging said second capacitor to a predetermined voltage, for interrupting the first firing current, thereby quenching said first flashtube, and a second circuit comprising said second flashtube and said second capacitor, responsive to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, the improvement comprising: (a) initiating means for applying an initial trigger voltage to said first electrode for triggering said first flashtube; and (b) current-sensitive means, coupling said first circuit to said second electrode, for triggering said second flashtube in response to the interruption of the first firing current, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses.

Claim 3

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means having first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating means for applying an initial trigger voltage to said first electrode for triggering said first flashtube; (c) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first state, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube, and to charge said second capacitor, and (2) a second state, occurring in response to charging said second capacitor to a predetermined level relative to the charge on said first capacitor, for interrupting the first firing current, thereby quenching said first flashtube and causing said second winding to produce a flashtube trigger voltage; (d) means, coupling said second electrode to said second winding, for triggering said second flashtube in response to the flashtube trigger voltage; and (e) a second circuit comprising said second flashtube and said second capacitor, responsive to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses.

Claim 4

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means having first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating means for applying an initial trigger voltage to said first electrode for triggering said first flashtube; (c) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first state, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube, and to charge said second capacitor, and (2) a second state, occurring in response to charging said second capacitor to a predetermined level relative to the charge on said first capacitor, for interrupting the first firing current, thereby quenching said first flashtube and causing said second winding to produce a flashtube trigger voltage; (d) means, coupling said second electrode to said second winding, for triggering said second flashtube in response to the flashtube trigger voltage; and (e) a second circuit comprising said second flashtube and said second capacitor, responsive to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses.

Claim 5

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce respective light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means comprising first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating circuitry, including a third capacitor chargeable by said capacitor charging means, said transformer means, and an actuatable switch having an actuated state for discharging said third capacitor through said first winding to produce a flashtube trigger voltage across said second winding; (c) first switch means, coupling said first electrode to said second winding, responsive to the flashtube trigger voltage when said third capacitor is discharged, for applying a voltage to said first electrode to initially trigger said first flashtube; (d) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first condition, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube, and to charge said second capacitor, and (2) a second condition, occurring in response to charging said second capacitor to a given level relative to the charge on said first capacitor, for interrupting the first firing current, thereby quenching said first flashtube and causing said second winding to produce a flashtube trigger voltage; (e) second switch means, coupling said second electrode to said second winding, responsive to the flashtube trigger voltage when the first firing current is interrupted, for applying a voltage to said second electrode to trigger said second flashtube; and (f) a second circuit, including said second flashtube and said second capacitor, reponsive to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses.

Claim 6

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce respective light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means comprising first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating circuitry, including a third capacitor chargeable by said capacitor charging means, said transformer means, and an actuatable switch having an actuated state for discharging said third capacitor through said first winding to produce a flashtube trigger voltage across said second winding; (c) first switch means, coupling said first electrode to said second winding, responsive to the flashtube trigger voltage when said third capacitor is discharged, for applying a voltage to said first electrode to initially trigger said first flashtube; (d) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first condition, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube, and to charge said second capacitor, and (2) a second condition, occurring in response to charging said second capacitor to a given level relative to the charge on said first capacitor, for interrupting the first firing current, thereby quenching said first flashtube and causing said second winding to produce a flashtube trigger voltage; (e) second switch means, coupling said second electrode to said second winding, responsive to the flashtube trigger voltage when the first firing current is interrupted, for applying a voltage to said second electrode to trigger said second flashtube; and (f) a second circuit, including said second flashtube and said second capacitor, reponsive to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses.

Claim 7

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, means for charging said first capacitor, a first circuit comprising said first flashtube connected between said first and second capacitors, and having (1) a first condition, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube, and to charge said second capacitor, and (2) a second condition, occurring in response to charging said second capacitor to a first given voltage, for interrupting the first firing current, thereby quenching said first flashtube, and a second firing circuit comprising said second flashtube and said second capacitor, and having (1) a first condition, occurring in response to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, and (2) a second condition, occurring in response to discharging said second capacitor to a second given voltage, for interrupting the second firing current, thereby quenching said second flashtube, the improvement comprising: (a) initiating means for applying an initial voltage to said first electrode for triggering said first flashtube; (b) current-sensitive means, coupling said first and second circuits to said second and first electrodes, respectively, for triggering said second flashtube in response to the interruption of the first firing current and for triggering said first flashtube in response to the interruption of the second firing current, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses; and (c) control means, responsive to the occurrence of a predetermined exposure parameter, for overriding said current-sensitive means to terminate the production of light pulses.

Claim 8

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, means for charging said first capacitor, a first circuit comprising said first flashtube connected between said first and second capacitors, and having (1) a first condition, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first circuit to fire said first flashtube, and to charge said second capacitor, and (2) a second condition, occurring in response to charging said second capacitor to a first given voltage, for interrupting the first firing current, thereby quenching said first flashtube, and a second firing circuit comprising said second flashtube and said second capacitor, and having (1) a first condition, occurring in response to triggering said second flashtube, for causing a second firing current to flow from said second capacitor to fire said second flashtube, and (2) a second condition, occurring in response to discharging said second capacitor to a second given voltage, for interrupting the second firing current, thereby quenching said second flashtube, the improvement comprising: (a) initiating means for applying an initial voltage to said first electrode for triggering said first flashtube; (b) current-sensitive means, coupling said first and second circuits to said second and first electrodes, respectively, for triggering said second flashtube in response to the interruption of the first firing current and for triggering said first flashtube in response to the interruption of the second firing current, whereby said first and second flashtubes are fired sequentially to produce sequential light pulses; and (c) control means, responsive to the occurrence of a predetermined exposure parameter, for overriding said current-sensitive means to terminate the production of light pulses.

Claim 9

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce respective light pulses, first and second capacitors for supplying firing contents to said first and second flashtubes, respectively, for causing them to produce light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means comprising first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating means for applying a flashtube trigger voltage to said first electrode to initially trigger said first flashtube; (c) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first condition, occuring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first flashtube, said second capacitor and said first winding to fire said first flashtube and to charge said second capacitor, and (2) a second condition, occurring in response to charging said second capacitor to a first given level relative to the charge on said first capacitor, for interrupting the first firing current to quench said first flashtube and to cause said second winding to produce a first flashtube trigger voltage; (d) a second circuit comprising said second flashtube, said second firing capacitor, and said first winding, and having (1) a first condition, occurring in response to triggering said second flashtube, for causing a second firing current to flow from said second capacitor through said second flashtube and said first winding to fire said second flashtube, and (2) a second condition, occurring in response to discharging said second capacitor to a second given level, for interrupting the second firing current to quench said second flashtube and to cause said second winding to produce a second flashtube trigger voltage; (e) switch means connecting said second winding to said first and second electrodes, and having (1) a first state, occurring in response to the first flashtube trigger voltage for applying a voltage to said second electrode to trigger said second flashtube, and (2) a second state, occurring in response to the second flashtube trigger voltage for applying a voltage to said first electrode to trigger said first flashtube, whereby said first and second flashtubes are fired alternately for producing alternate light pulses; and (f) control means, reponsive to the occurrence of a predetermined exposure parameter, for causing current to bypass said first winding to prevent the production of a flashtube trigger voltage, whereby the light pulses are terminated.

Claim 10

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce respective light pulses, first and second capacitors for supplying firing contents to said first and second flashtubes, respectively, for causing them to produce light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means comprising first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating means for applying a flashtube trigger voltage to said first electrode to initially trigger said first flashtube; (c) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first condition, occuring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first flashtube, said second capacitor and said first winding to fire said first flashtube and to charge said second capacitor, and (2) a second condition, occurring in response to charging said second capacitor to a first given level relative to the charge on said first capacitor, for interrupting the first firing current to quench said first flashtube and to cause said second winding to produce a first flashtube trigger voltage; (d) a second circuit comprising said second flashtube, said second firing capacitor, and said first winding, and having (1) a first condition, occurring in response to triggering said second flashtube, for causing a second firing current to flow from said second capacitor through said second flashtube and said first winding to fire said second flashtube, and (2) a second condition, occurring in response to discharging said second capacitor to a second given level, for interrupting the second firing current to quench said second flashtube and to cause said second winding to produce a second flashtube trigger voltage; (e) switch means connecting said second winding to said first and second electrodes, and having (1) a first state, occurring in response to the first flashtube trigger voltage for applying a voltage to said second electrode to trigger said second flashtube, and (2) a second state, occurring in response to the second flashtube trigger voltage for applying a voltage to said first electrode to trigger said first flashtube, whereby said first and second flashtubes are fired alternately for producing alternate light pulses; and (f) control means, reponsive to the occurrence of a predetermined exposure parameter, for causing current to bypass said first winding to prevent the production of a flashtube trigger voltage, whereby the light pulses are terminated.

Claim 11

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce respective light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means comprising first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating means for applying a trigger voltage to said first electrode to initially trigger said first flashtube; (c) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first condition, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first flashtube, said second capacitor and said first winding, to fire said first flashtube, and to charge said second capacitor, and (2) a second condition, occurring in response to the first firing current charging said second capacitor to a first given level relative to the charge on said second capacitor, for interrupting the first firing current, thereby quenching said first flashtube and causing said second winding to produce a flashtube trigger voltage; (d) a second circuit comprising said second flashtube, said second firing capacitor, and said first winding, and having (1) a first condition, occurring in response to triggering said second flashtube, for causing a second firing current to flow from said second capacitor through said second flashtube and said first winding, to fire said second flashtube, and (2) a second condition, occurring in response to the second firing current discharging said second capacitor to a second given level, for interrupting the second firing current, thereby quenching said second flashtube and causing said second winding to produce a flashtube trigger voltage; (e) a first diode connecting said second winding to said first electrode, and a second diode connecting said second winding to said second electrode, said first and second diodes being arranged such that (1) said first diode conducts in response to the flashtube trigger voltage when the second firing current is interrupted to apply a voltage to said first electrode to trigger said first flashtube, and (2) said second diode conducts in response to the flashtube trigger voltage when the first firing current is interrupted to apply a voltage to said second electrode to trigger said second flashtube, whereby said first and second flashtubes are fired alternately into conduction for producing alternate light pulses repeatedly; and (f) control means, responsive to the occurrence of a predetermined exposure parameter, for causing the second firing current to bypass said first winding to prevent the production of a flashtube trigger voltage when the second firing current is interrupted whereby the light pulses are terminated.

Claim 12

In electronic flash apparatus comprising first and second flashtubes having first and second electrodes, respectively, for triggering their respective flashtubes into conduction to produce respective light pulses, first and second capacitors for supplying firing currents to said first and second flashtubes, respectively, for causing them to produce respective light pulses, and means for charging said first capacitor, the improvement comprising: (a) transformer means comprising first and second windings, said second winding being adapted to produce a flashtube trigger voltage in response to interrupting current in said first winding; (b) initiating means for applying a trigger voltage to said first electrode to initially trigger said first flashtube; (c) a first circuit comprising said first flashtube, said first and second capacitors, and said first winding, and having (1) a first condition, occurring in response to triggering said first flashtube, for causing a first firing current to flow from said first capacitor through said first flashtube, said second capacitor and said first winding, to fire said first flashtube, and to charge said second capacitor, and (2) a second condition, occurring in response to the first firing current charging said second capacitor to a first given level relative to the charge on said second capacitor, for interrupting the first firing current, thereby quenching said first flashtube and causing said second winding to produce a flashtube trigger voltage; (d) a second circuit comprising said second flashtube, said second firing capacitor, and said first winding, and having (1) a first condition, occurring in response to triggering said second flashtube, for causing a second firing current to flow from said second capacitor through said second flashtube and said first winding, to fire said second flashtube, and (2) a second condition, occurring in response to the second firing current discharging said second capacitor to a second given level, for interrupting the second firing current, thereby quenching said second flashtube and causing said second winding to produce a flashtube trigger voltage; (e) a first diode connecting said second winding to said first electrode, and a second diode connecting said second winding to said second electrode, said first and second diodes being arranged such that (1) said first diode conducts in response to the flashtube trigger voltage when the second firing current is interrupted to apply a voltage to said first electrode to trigger said first flashtube, and (2) said second diode conducts in response to the flashtube trigger voltage when the first firing current is interrupted to apply a voltage to said second electrode to trigger said second flashtube, whereby said first and second flashtubes are fired alternately into conduction for producing alternate light pulses repeatedly; and (f) control means, responsive to the occurrence of a predetermined exposure parameter, for causing the second firing current to bypass said first winding to prevent the production of a flashtube trigger voltage when the second firing current is interrupted whereby the light pulses are terminated.