Memory switch controls for cameras

• US 3,887,932 A
• Filed: 09/19/1973
• Issued: 06/03/1975
• Est. Priority Date: 09/21/1972
• Status: Expired due to Term

• Current Assignee: Katsuhiko Nomura, Naoyuki Uno
• Original Assignee: Katsuhiko Nomura, Naoyuki Uno
• Inventors: Uno, Naoyuki, Nomura, Katsuhiko
• Primary Examiner(s): Wintercorn, Richard A.
• Application Number:
  US05/398,806
• Time in Patent Office: 622 Days
• Field of Search: 354/152,156,50,51,60,258
• US Class Current: 396/358
• CPC Class Codes: G03B 7/087 for control of both exposure time and aperture
• CPC Class Codes: G03B 7/089 for storage of exposure value in mirror reflex cameras

Abstract

A structure for controlling the memory switch of a single lens reflex camera in which a mirror directs light from the objective to a light-measuring structure. Just prior to exposure the mirror is swung up to permit light to reach the film, and when the mirror is swung up light can no longer reach the light-measuring structure. A structure which blocks the drive of the mirror to its upper position cooperates with the memory switch to place the latter in an operative position when the blocking structure moves to a release position releasing the mirror drive for operation, so that in this way the memory switch is rendered operative prior to swinging of the mirror to its upper position.

Claims

1. In a single lens reflex camera which measures light internally and which has a swingable mirror normally occupying a lower viewing position where said mirror reflects light which has travelled through the objective to a light-measuring structure and being swingable from said lower position to an upper exposure position where light travelling through the objective no longer reaches the light-measuring structure, memory switch means movable between a normal inactive position and an operative position enabling a memory structure to retain information received by the light-measuring structure, said memory switch means having an inherent force which acts to maintain said memory switch means in said inactive position, mirror-drive means cooperating with the mirror to drive the latter upwardly from said lower viewing position to said upper exposure position, switch-operating means cooperating with said memory switch means for displacing the latter in opposition to said inherent force from said normal inactive position to said operative position, said switch-operating means having a rest position cooperating with said mirror-drive means to prevent operation thereof, said switch-operating means being movable from said rest position thereof for placing said memory switch means in said operative position thereof, while said switch-operating means also releases said mirror-drive means for operation to drive said mirror to said exposure position thereof, and manually operable release means to be set into motion by the operator of the camera for carrying out operations in connection with shutter release, said manually operable release means cooperating with said switch-operating means for moving the latter to place said memory switch means in said operative position thereof, whereby said mirror-drive means will not be released to drive the mirror upwardly to its exposure position until after said memory switch means has been placed by said switchoperating means in said operative position thereof.

2. The combination of claim 1 and wherein said manually operable release means includes a lever means acting on said switch-operating means for controlling the position of the latter and a spring means acting on said lever means for urging the latter to move said switchoperating means for placing said memory switch means in said operative position thereof, said manually operable means also including a manually operable release member retaining said lever means in opposition to said spring means in an initial position where said switch-operating means is in said rest position thereof, said release member being movable by the operator for releasing said lever means to the force of said spring means so that said lever means will then move said switch-operating means to place said memory switch means in said operative position thereof while releasing said mirror-drive means for operation.

3. The combination of claim 2 and wherein a diaphragm control means is operatively connected with said spring means to be urged thereby to a given position, so that said spring means acts both on said diaphragm-control means and said lever means.

4. The combination of claim 3 and wherein said mirror-drive means also cooperates with said diaphragm-control means for displacing the latter from said given position to which it is urged by said spring means when said mirror-drive means is released for operation upon movement of said switch-operating means to place said memory switch means in said operative position thereof.

5. The combination of claim 4 and wherein a shutter-tripping means is operatively connected with said mirror-drive means to be driven thereby to trip a shutter of the camera, so that the release of the mirror-drive means to displace the diaphragm-control means from said given position thereof and to drive the mirror upwardly to its exposure position and drive the shutter-tripping means does not take place until said switch-operating means operates to place said memory switch means in said operative position thereof.

6. The combination of claim 1 and wherein said memory switch means includes a springy component acting to maintain said memory switch means in its normal inactive position and said switch-operating means in its rest position.

7. The combination of claim 2 and wherein said switch-operating means includes a swingable lever, said lever means carrying a pin engaging said swingable lever for turning the latter when said lever means is released to said spring means by movement of said release member for actuating the switch-operating means to place said memory switch means in its operative position.

8. The combination of claim 1 and wherein said switch-operating means when in said rest position thereof has a portion situated in the path of movement of part of said mirror-drive means to prevent operation thereof, said memory switch means acting with said inherent force thereof on said switch-operating means for maintaining the latter in said rest position thereof.

9. The combination of claim 8 and wherein said mirror-drive means and switch-operating means both include a pair of levers which have parallel turning axes, said lever of said mirror-drive means having an arm and said lever of said switch-operating means having an arm situated in the path of movement of said arm of said lever of said mirror-drive means when said switch-operating means is in said rest position thereof, said manually operable release means including a lever having a pin engaging said lever of said switch-operating means to turn the arm of the latter away from the path of movement of said arm of said lever of said mirror-drive means when said switch-operating means is actuated by said manually operable release means to place said memory switch means in said operative position thereof.