Photographic camera with electronic flash having periodically disabled charging apparatus

• US 4,641,943 A
• Filed: 10/30/1985
• Issued: 02/10/1987
• Est. Priority Date: 10/30/1985
• Status: Expired due to Term

• Current Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Original Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Inventors: Neely, Judith L.
• Primary Examiner(s): Gellner, Michael L.
• Application Number:
  US06/792,869
• Time in Patent Office: 468 Days
• Field of Search: 354/413, 354/235.1
• US Class Current: 396/206
• CPC Class Codes: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 2215/0503 Built-in units

Abstract

A photographic camera having a single source of internal electrical power, an electronic flash that includes a flashtube and a charging system for storing an electrical charge for subsequent discharge across the light emitting element of the flashtube, a manually actuatable self-timer for generating an exposure interval initiating electrical signal a predetermined time after the timing cycle of the self-timer has been actuated and apparatus for generating electrically produced visual and/or audible signals indicating that the self-timer is in operation is provided with apparatus for inhibiting the operation of the electronic flash charging system whenever such signals are generated in order to prevent the relatively large electrical load associated with the electronic flash charging system from changing the voltage and/or current levels available from the camera'"'"'s power source and thereby preclude interferance with the proper operation of the self-timer operation indicators which are sensitive to such changes.

Claims

1. Apparatus for inhibiting the charging of an electronic flash in a photographic camera having a self-timer, whenever a particular function is generated during self-timer operation, comprising:

a manually actuatable self-timer for generating a film exposure sequence initiating electrical signal a predetermined time after the timing cycle of said self-timer has been initiated;

an electronic flash including a flashtube and a charging system for storing an electrical charge for subsequent discharge across the light emitting element of said flashtube during an exposure interval;

means responsive to the operation of said self-timer for generating a particular function during the operation of said self-timer; and

control means for enabling the electronic flash to operate in a charge mode during said self-timer timing cycle and for inhibiting the operation of said charging system during said timing cycle whenever said particular function is generated.

2. The apparatus of claim 1 wherein the said particular function generated during the operation of said self-timer is a visual signal indicating that the self-timer is in operation.

3. The apparatus of claim 2 wherein the said visual signal indicating that the self-timer is in operation is a source of light from a light-emitting diode.

4. The apparatus of claim 2 wherein the said particular function generated during the operation of said self-timer is an audible signal indicating that the self-timer is in operation.

5. The apparatus of claim 4 wherein the said audible signal indicating that the self-timer is in operation is a vibratory sound produced by a piezoelectric buzzer.

6. Apparatus for inhibiting the charging of an electronic flash in a photographic camera having a self-timer, whenever an indicator indicative of self-timer operation is activated, comprising:

a manually actuatable self-timer for generating a film exposure sequence initiating electrical signal a predetermined time after the timing cycle of said self-timer has been initiated;

an electronic flash including a flashtube and a charging system for storing an electrical charge for subsequent discharge across the light emitting element of said flashtube during an exposure interval;

means responsive to the operation of said self-timer for generating a visual and/or audible signal indicative of self-timer operation; and

control means for enabling the electronic flash to operate in a charge mode during said self-timer timing cycle and for inhibiting the operation of said charging system during said timing cycle whenever a self-timer operation indicator is activated.

7. The apparatus of claim 6 wherein said control means includes a pulse generator for producing a train of pulses in response to the operation of said self-timer and wherein said charging system in inhibited and said self-timer operation indicator is activated for the duration of each of the pulses forming said pulse train.

8. The apparatus of claim 7 wherein the period of time between adjacent pulses in said pulse train becomes progressively shorter.

9. The apparatus of claim 6 wherein the visual signal responsive to the operation of said self-timer and indicative of self-timer operation is produced by a light emitting diode.

10. The apparatus of claim 6, wherein the audible signal responsive to the operation of said self-timer operation is provided by a piezoelectric buzzer.