US3898514A - Strobo discharge device with audio signal generator - Google Patents

Strobo discharge device with audio signal generator Download PDF

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Publication number
US3898514A
US3898514A US365085A US36508573A US3898514A US 3898514 A US3898514 A US 3898514A US 365085 A US365085 A US 365085A US 36508573 A US36508573 A US 36508573A US 3898514 A US3898514 A US 3898514A
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United States
Prior art keywords
continuous wave
signal
voltage
capacitor
main
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Expired - Lifetime
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US365085A
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English (en)
Inventor
Akira Takahashi
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Ricoh Co Ltd
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Ricoh Co Ltd
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Publication date
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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14Circuit arrangements
    • H05B41/30Circuit arrangements in which the lamp is fed by pulses, e.g. flash lamp
    • H05B41/34Circuit arrangements in which the lamp is fed by pulses, e.g. flash lamp to provide a sequence of flashes

Definitions

  • FIG. 4 T1 i TO
  • the present invention relates to a strobo discharge device, and more particularly to a strobo discharge device which generates audio signals when a main flash capacitor is charged to a potential which is in excess of a predetermined level.
  • a neon bulb is generally used in order to indicate that the voltage across the main flash capacitor is above a predetermined level.
  • an operator may see the light from the neon bulb within or outside the viewfinder.
  • a rapid sequence of successive shots becomes difficult because the operator must, for each shot, determine framing and focusing and check whether the main flash capacitor is ready to trigger a flash bulb while simultaneously looking through the viewfinder.
  • the operator In the case of a camera of the type in which a neon bulb is disposed outside the viewfinder, the operator must remove his eye from the viewfinder in order to check the neon bulb every time he takes a shot.
  • One of the objects of the present invention is therefore to provide a strobo discharge device which generates audio signals when the main flash capacitor is charged to a potential in excess of a predetermined voltage.
  • Another object of the present invention is to provide a strobo discharge device of the type described above which is simple in construction.
  • a voltage detecting means detects that the voltage across a main flash capacitor is in excess of a predetermined level
  • continuous wave voltage output signals from a continuous voltage generating means such as blocking oscillator
  • switching means such as an astable multivibrator
  • audio signals are generated when the voltage across the main flash capacitor exceeds a predetermined level so that an operator need not move his eye from a viewfinder in order to check the charging condition of the main flash capacitor. Furthermore the problem of framing, focusing and checking the charging condition of the main flash capacitor through the viewfinder is eliminated. Since the continuous wave voltage is intermittently interrupted and converted into audio signals, the audio signals may be readily discernible, and furthermore the frequency of the audio signals may be varied as desired in accordance with one of the embodiments of the present invention.
  • the continuous wave voltage source also functions as a blocking oscillator for charging a main flash capacitor so that the construction may be simplified and the cost may be reduced.
  • FIG. 1 is a block diagram of a strobo discharge device in accordance with the present invention
  • FIG. 2 shows the waveforms derived from the component parts thereof and used for the explanation of the mode of operation thereof;
  • FIG. 3 is a circuit diagram of a first embodiment of the present invention.
  • FIG. 4 is a circuit diagram of a variation thereof.
  • FIGS. 5 and 6 are circuit diagrams of second and third embodiments of the present invention, respectively.
  • FIGS. 1 and 2 a voltage detector 1 detects whether the voltage across a main capacitor is sufficient to trigger a flash tube.
  • a continuous wave voltage source 2 comprises for example a blocking oscillator; a switching means 3 comprises an astable multivibrator; and a speaker 4 may comprise an earphone.
  • a continuous wave voltage (See FIG. 2(a)) from the continuous wave voltage source 2 is intermittently interrupted by the switching means 3 (See FIG. 2(b)) and is applied to the speaker 4 so as to generate sound signals (See FIG. 2(c)).
  • FIGS. 3 and 4 Referring to FIG. 3, a blocking oscillator 6 is connected to a DC power source 5 and charges a main capacitor 7. Since the blocking oscillator 6 may be any conventional self-running blocking oscillator, a detailed description of its construction and mode of operation will not be given in this specification.
  • the blocking oscillator 6 includes a transformer T so as to provide output voltage higher than the voltage supplied from the DC power source 5. When the voltage across the main capacitor 7 exceeds a predetermined level, a neon bulb 8 is turned on. Since a voltage divider consisting of resistors IR and R is connected in parallel with the main capacitor 7, the voltage across the resistor R is applied across the neon bulb 8.
  • the voltage which triggers the neon bulb 8 is determined by the voltage across the main capacitor 7 and the values of the resistors R and R
  • the resistance of a photo cell, such as CdS cell 9 is reduced so that the base potential of a transistor Tr 1 falls.
  • the transistor Tr is turned on so that the switching means comprising astable multivibrator 10 starts oscillating.
  • a transistor Tr is intermittently turned on as shown at (b) in FIG. 2. Since the astable multivibrator 10 is of the conventional type, a detailed description of its construction and mode of operation will not be given in the specification.
  • a capacitor 13 When the main capacitor 7 is charged to a predetermined voltage, a capacitor 13 is charged through a resistor R to a predetermined voltage for triggering a flash tube 14.
  • a contact (not shown) on the side of the camera connected to a plug 15 is closed, and the capacitor 13 is discharged through the primary of a transformer T so that the flash tube 14 is triggered in response to the trigger signal generated by the transformer T
  • a contact 16 is used to check whether the flash tube 14 is ready to be triggered or not.
  • the parts similar to those shown in FIG. 3 are designated by same reference numerals.
  • the neon bulb 8 is connected in series to a resistor R and in parallel with the main capacitor 7 so that the voltage across the main capacitor 7 may be detected from a voltage at the junction S between the neon bulb 8 and the resistor R
  • the neon bulb 8 is turned on so that its resistance is reduced.
  • the voltage at the junction S rises so that the base potential of a transistor Tr rises, whereby the latter is turned on.
  • the astable multivibrator 10 is triggered so that the sound signals are generated through the earphone 12 as is the case of the first embodiment described in connection with FIG. 3.
  • the second embodiment is more advantageous than the first embodiment in that the photo cell 9 may be eliminated.
  • the circuit for detecting whether the voltage across the main capacitor exceeds a predetermined level or not also functions as a switching circuit 19 for temporarily interrupting the charging of the main capacitor 7 and intermittently interrupting the continuous wave voltage. That is, the collector-emitter circuit of a transistor Tr is connected in parallel with the baseemitter circuit of the transistor Tr and the base of the transistor Tr the resistor R and one electrode of the neon bulb 8 are connected in series. The other electrode of the neon bulb 8 is connected to the output of the blocking oscillator 6. When the main capacitor 7 is charged in excess of a predetermined level, the neon bulb 8 turns on and starts conducting so that the transistor Tr is turned on.
  • the base potential of the transistor Tr falls so that the transistor Tr is cut off.
  • the blocking oscillator 6 is stopped.
  • the main capacitor 7 is naturally discharged or discharged through a vaiable resistor VR, connected in parallel with the main capacitor 7, the neon bulb 8 and the transistor Tr are cut off so that the blocking oscillator 6 is triggered again.
  • the earphone 12 generates the intermittent sound signals.
  • the variable resistor VR By adjusting the variable resistor VR, the frequency of the intermittent sound signals may be varied.
  • the functions of the voltage detector and the switching circuit can be accomplished by a common circuit so that the astable multivibrator used in the first and second embodiments may be eliminated.
  • a further advantage of the third embodiment is that the voltage across the main capacitor may be maintained within a predetermined range.
  • a strobo discharge device comprising a. a flash tube,
  • g. means for converting said intermittently interrupted continuous wave voltage into sound signals.
  • said voltage detecting means comprises a neon bulb across which is applied a part of the voltage across said main capacitor and a photoelectric cell disposed to intercept the light emitted from said neon bulb,
  • said means for intermittently interrupting the continuous wave voltage comprises an astable multivibrator
  • said means for converting said intermittently interrupted continuous wave voltage into sound signals comprises a speaker system, whereby said continuous wave voltage is derived from said blocking oscillator and the signals for intermittently interrupting said continuous wave voltage are derived from said astable multivibrator.
  • a strobo discharge device having a flashtube having two main terminals and a trigger terminal and firing when a firing signal exceeding a selected value is applied to its main terminal and a trigger signal is applied to its trigger terminal, means for storing a firing signal connected across the main terminals of the flashtube, means for gradually charging the storing means from a level below said selected value to a level exceeding said selected value, and first normally open switch means closeable to apply a trigger signal to the trigger terminal of the flashtube to fire it when a firing signal exceeding the selected value is applied to the main terminals of the tube, wherein the improvement comprises a device for audibly indicating when the storage means stores a firing signal exceeding said preselected value, comprising:
  • the converting means provides an intermittent audible signal when the storage means stores a firing signal of a level sufficient for firing the flash tube, to indicate to an operator that closing of said first switch means would fire the flash tube.
  • a device as in claim 5 wherein the means for generating said continuous wave form signal is a blocking oscillator.
  • the detecting means comprise a neon bulb across which is applied a selected portion of the voltage across said capacitor and a photoelectric cell disposed to intercept the light from the neon bulb.
  • a device as in claim 7 wherein the means for intermittently closing the second switch means comprise an astable multivibrator.

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  • Stroboscope Apparatuses (AREA)
  • Discharge-Lamp Control Circuits And Pulse- Feed Circuits (AREA)
US365085A 1972-05-30 1973-05-30 Strobo discharge device with audio signal generator Expired - Lifetime US3898514A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP47053573A JPS522619B2 (de) 1972-05-30 1972-05-30

Publications (1)

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US3898514A true US3898514A (en) 1975-08-05

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Application Number Title Priority Date Filing Date
US365085A Expired - Lifetime US3898514A (en) 1972-05-30 1973-05-30 Strobo discharge device with audio signal generator

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US (1) US3898514A (de)
JP (1) JPS522619B2 (de)
CA (1) CA997410A (de)
DE (1) DE2327681C3 (de)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4013921A (en) * 1975-06-02 1977-03-22 Austin Electronics, Inc. Warning light control
US4074244A (en) * 1975-07-18 1978-02-14 Balderson Robert Bruce Audible-visual warning alarm system
US4099100A (en) * 1975-07-11 1978-07-04 Nippon Kogaku K.K. Neon tube flashing device
US4163178A (en) * 1976-04-16 1979-07-31 Fuji Photo Optical Co., Ltd. Flash light discharge device
US4241332A (en) * 1979-02-05 1980-12-23 Body Guard, Inc. Personal security alarm
US4274084A (en) * 1979-10-26 1981-06-16 Wheelock Signals, Inc. Audio-visual signal circuits
EP0035261A1 (de) * 1980-02-27 1981-09-09 Olympus Optical Co., Ltd. Automatische Blitzlichtvorrichtung
US4295717A (en) * 1978-05-31 1981-10-20 Olympus Optical Company, Ltd. Camera with operation indicator for auto-strobo unit
US4301392A (en) * 1979-04-09 1981-11-17 West Electric Co., Ltd. Electronic flash system capable of automatic flash duration control
US4306281A (en) * 1979-10-08 1981-12-15 Canon Kabushiki Kaisha DC-DC Converter for electronic flash unit
EP0047892A1 (de) * 1980-09-11 1982-03-24 Robert Bosch Gmbh Elektronenblitzgerät mit automatischer Blitzlichtmengenbegrenzung
US5144301A (en) * 1991-02-19 1992-09-01 Jackson Timothy C School bus locator system

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3778672A (en) * 1972-07-27 1973-12-11 Ponder & Best Audible alert signal for an electronic flash unit
JPS51152278U (de) * 1975-05-29 1976-12-04
JPS52146140U (de) * 1976-04-30 1977-11-05
JPS52155039U (de) * 1976-05-19 1977-11-25
JPS60149034A (ja) * 1984-09-07 1985-08-06 Olympus Optical Co Ltd 自動調光式ストロボの動作表示装置

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3310723A (en) * 1963-10-18 1967-03-21 Honeywell Inc High voltage power supply for photographic flash apparatus
US3757697A (en) * 1972-02-02 1973-09-11 Bendix Corp Remotely controlled blasting machine

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3310723A (en) * 1963-10-18 1967-03-21 Honeywell Inc High voltage power supply for photographic flash apparatus
US3757697A (en) * 1972-02-02 1973-09-11 Bendix Corp Remotely controlled blasting machine

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4013921A (en) * 1975-06-02 1977-03-22 Austin Electronics, Inc. Warning light control
US4099100A (en) * 1975-07-11 1978-07-04 Nippon Kogaku K.K. Neon tube flashing device
US4074244A (en) * 1975-07-18 1978-02-14 Balderson Robert Bruce Audible-visual warning alarm system
US4163178A (en) * 1976-04-16 1979-07-31 Fuji Photo Optical Co., Ltd. Flash light discharge device
US4271375A (en) * 1976-04-16 1981-06-02 Fuji Photo Optical Co., Ltd. Flash light discharge device
US4295717A (en) * 1978-05-31 1981-10-20 Olympus Optical Company, Ltd. Camera with operation indicator for auto-strobo unit
US4241332A (en) * 1979-02-05 1980-12-23 Body Guard, Inc. Personal security alarm
US4301392A (en) * 1979-04-09 1981-11-17 West Electric Co., Ltd. Electronic flash system capable of automatic flash duration control
US4306281A (en) * 1979-10-08 1981-12-15 Canon Kabushiki Kaisha DC-DC Converter for electronic flash unit
US4274084A (en) * 1979-10-26 1981-06-16 Wheelock Signals, Inc. Audio-visual signal circuits
EP0035261A1 (de) * 1980-02-27 1981-09-09 Olympus Optical Co., Ltd. Automatische Blitzlichtvorrichtung
US4344684A (en) * 1980-02-27 1982-08-17 Olympus Optical Co., Ltd. Automatic photoflash device
EP0047892A1 (de) * 1980-09-11 1982-03-24 Robert Bosch Gmbh Elektronenblitzgerät mit automatischer Blitzlichtmengenbegrenzung
US5144301A (en) * 1991-02-19 1992-09-01 Jackson Timothy C School bus locator system

Also Published As

Publication number Publication date
CA997410A (en) 1976-09-21
DE2327681B2 (de) 1975-02-20
JPS522619B2 (de) 1977-01-22
DE2327681C3 (de) 1975-10-02
JPS4916420A (de) 1974-02-13
DE2327681A1 (de) 1973-12-13

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