Camera capable of flash photography

• US 4,761,666 A
• Filed: 07/15/1987
• Issued: 08/02/1988
• Est. Priority Date: 07/20/1986
• Status: Expired due to Term

• Current Assignee: Nikon Corporation
• Original Assignee: Nippon Kogaku K. K. (Nikon Corporation)
• Inventors: Goto, Tetsuro
• Primary Examiner(s): Gellner, Michael L.
• Application Number:
  US07/073,471
• Time in Patent Office: 384 Days
• Field of Search: 354/133, 354/146, 354/147
• US Class Current: 396/183
• CPC Class Codes: G03B 9/70 with flash-synchronising contacts

Abstract

In a camera having a focal plane shutter, a magnet restrains the rearward shutter curtain in response to the supply of power to the magnet. A control device controls the period of power supply, and the restraint of the rearward shutter curtain is released when the power supply is terminated. A detecting circuit detects the termination of the power supply and outputs a detection signal. Another detecting circuit responsive to the movement of the forward shutter curtain outputs another detection signal. A selector selects one of the detection signals and inputs the selected signal to a starting circuit, which responds to the selected signal to start a flash emission.

Claims

1. A camera in which exposure of a film is accomplished by movement of the forward shutter curtain of a focal plane shutter and movement of the rearward shutter curtain of the focal plane shutter, including:

magnet means for restraining the rearward shutter curtain of said focal plane shutter by a magnetic force;

power supply means for supplying power to said magnet means, said magnet means being adapted to produce a magnetic force in response to the supply of power by said power supply means;

control means for controlling the period of power supply of said power supply means, said magnet means being adapted to release the restraint of said rearward shutter curtain in respone to the termination of said power supply;

a detecting circuit electrically connected to said power supply means for electrically detecting the termination of the power supply by said power supply means and outputting a detection signal;

another detecting circuit responsive to the movement of the forward shutter curtain of said focal plane shutter to output another detection signal;

flash emitting means for emitting flash toward an object to be photographed;

a starting circuit; and

selecting means for selecting one of said detection signals and inputting the selected signal to said starting circuit, said starting circuit being responsive to the signal selected by said selecting means to start the flash emission of said flash emitting means.

2. A camera according to claim 1, wherein said selecting means has an operating member, and said selecting means is responsive to the operation of said member to select one of said detection signal and said another detection signal.

3. A camera in which exposure of a film is accomplished by movement of the forward shutter curtain of a focal plane shutter and movement of the rearward shutter curtain of the focal plane shutter, including:

magnet means for restraining the rearward shutter curtain of said focal plane shutter by a magnetic force;

power supply means for supplying power to said magnet means, said magnet means being adapted to produce a magnetic force in response to the supply of power by said power supply means;

control means for outputting a stop signal for stopping the power supply of said power supply means and controlling the period of power supply of said power supply means, said magnet being responsive to the termination of said power supply to release the restraint of said rearward shutter curtain;

a detecting circuit electrically connected to said control means for electrically detecting that said stop signal has been output and outputting a detection signal;

another detecting circuit responsive to the movement of the forward shutter curtain of said focal plane shutter to output another detection signal;

flash emitting means for emitting flash toward an object to be photographed;

a starting circuit; and

selecting means for selecting one of said detection signals and inputting the selected signal to said starting circuit, said starting circuit being responsive to the signal selected by said selecting means to start the flash emission of said flash emitting means.

4. A camera according to claim 3, wherein said control means has terminal means for outputting said stop signal, and said detecting circuit is electrically connected to said terminal means.

5. A camera according to claim 3, wherein said selecting means has an operating member, and said selecting means is responsive to the operation of said member to select one of said detection signal and said another detection signal.

6. A camera in which exposure of a film is accomplished by movement of the forward shutter curtain of a focal plane shutter and movement of the rearward shutter curtain of the focal plane shutter, including:

magnet means for restraining the rearward shutter curtain of said focal plane shutter;

power supply means for supplying power to said magnet means, said magnet means being adapted to release the restraint of said rearward shutter curtain by being supplied with power by said power supply means;

starting means for causing said power supply means to start the supply of power to said magnet means;

a detecting circuit electrically connected to said power supply means for electrically detecting the start of the power supply to said magnet means and outputting a detection signal;

another detecting circuit responsive to the movement of the forward shutter curtain of said focal plane shutter to output another detection signal;

flash emitting means for emitting flash toward an object to be photographed;

a starting circuit; and

selecting means for selecting one of said detection signals and inputting the selected signal to said starting circuit, said starting circuit being responsive to the signal selected by said selecting means to start the flash emission of said flash emitting means.

7. A camera according to claim 6, wherein said selecting means has an operating member, and said selecting means is responsive to the operation of said member to select one of said detection signal and said another detection signal.

8. A camera in which exposure of a film is accomplished by movement of the forward shutter curtain of the focal plane shutter and movement of the rearward shutter curtain of the focal plane shutter, including:

magnet means for restraining the rearward shutter curtain of said focal plane shutter;

power supply means for supplying power to said magnet means, said magnet means being adapted to release the restraint of said rearward shutter curtain by being supplied with power by said power supply means;

control means for outputting a start signal for causing said power supply means to start the supply of power to said magnet means;

a detecting circuit electrically connected to said control means for electrically detecting that said start signal has been output and outputting a detection signal;

another detecting circuit responsive to the movement of the forward shutter curtain of said focal plane shutter to output another detection signal;

flash emitting means for emitting flash toward an object to be photographed;

a starting circuit; and

selecting means for selecting one of said detection signals and inputting the selected signal to said starting circuit, said starting circuit being responsive to the signal selected by said selecting means to start the flash emission of said flash emitting means.

9. A camera according to claim 8, wherein said control means has terminal means for outputting said start signal, and said detecting circuit is electrically connected to said terminal means.

10. A camera according to claim 8, wherein said selecting means has an operating member, and said selecting means is responsive to the operation of said member to select one of said detection signal and said another detection signal.