Shutter operating mechanism

Claim 2

A shutter operating mechanism comprising a shutter movable between open and closed positions, a movable shutter opening member connected with said shutter and spring biased to move in a shutter opening direction, means for releasably holding said shutter opening member in set position with the shutter in closed position, a movable shutter closing member connected with said shutter and spring biased to move in a shutter closing direction, electrically releasable means for holding said closing member in set position, an aperture control member selectively settable in a position for automatic shutter operation or in any of a plurality of semiautomatic positions for different aperture openingS, means for controlling the rate of opening of the shutter upon release of said shutter opening member when said aperture control member is in automatic position, timing circuit means controlling the release of said shutter closing member by said electrically releasable means including a timing switch means operable upon release of said shutter opening member and time delay means operable to release said shutter closing member a selected time period after actuation of said timing switch, said time delay means comprising a photosensitive element, a capacitance and resistance, and selector means controlled by the setting of said aperture control member is set in automatic position, and to control said time period jointly by said photosensitive element and the setting of said aperture control member when said aperture control member is set in a selected semiautomatic position.

Claim 3

Shutter opening mechanism according to claim 1, in which said means controlling the rate of opening of the shutter comprises a governor comprising a gear train and an escapement mechanism.

Claim 4

Shutter operating mechanism according to claim 1, comprising means actuated by said aperture control member for disabling said means controlling the rate of opening of the shutter when said aperture control member is set in a semiautomatic position.

Claim 5

Shutter operating mechanism according to claim 1, in which said electrically releasable means comprises an electromagnet, and in which said timing circuit means comprises at least one transistor controlling the flow of current in said electromagnet, the conduction of said transistor being controlled by said time delay means.

Claim 6

Shutter operating mechanism according to claim 4, in which said timing circuit means comprises a resistor adapted to be connected in parallel with said photosensitive element, and in which a switch means actuated by said aperture control member is operable to connect said resistor in parallel with said photosensitive element when said aperture control member is in automatic position and for disconnecting said resistor when aperture control member is in a semiautomatic position.

Claim 7

Shutter operating mechanism according to claim 4, in which said timing circuit means comprises a plurality of resistors of different value and switching means actuated by said aperture control member to connect said resistors selectively into circuit with said capacitance to vary said time period according to selected semiautomatic settings of said aperture control member and the light sensed by said photosensitive element.

Claim 8

A shutter operating mechanism comprising a shutter movable between open and closed position, a movable shutter opening member connected with said shutter and spring biased to move in a shutter opening direction, means for releasably holding said shutter opening member in set position with the shutter in closed position, a movable shutter closing member connected with said shutter and spring biased to move in a shutter closing direction, electrically releasable means for holding said closing member in set position, an exposure time control member settable in a position for automatic shutter operation or in any of a plurality of nonautomatic positions for different exposure times, an aperture control member selectively settable in a position for automatic shutter operation or in any of a plurality of nonautomatic positions for different aperture openings, means for controlling the rate of opening of the shutter upon release of said shutter opening member when said aperture control member is in automatic position, timing circuit means controlling the release of said shutter closing member by said electrically releasable means including a timing switch means operable upon release of said shutter opening member and time delay means operable to release said shutter closing member a selected time period after actuation of said timing switch, said time delay means comprising a photosensitive element, a capacitance and Resistance, and selector means controlled by the settings of said exposure time control member and said aperture control member to control said aperture opening and said time period by said photosensitive element when said exposure time control member and said aperture control member are both set in automatic position, to control said time period jointly by said photosensitive element and the setting of said aperture control member when said exposure time control member is set in automatic position and said aperture control member is set in a selected nonautomatic position, and to control said time period by the setting of said exposure time control member only when each of said control members is set in a selected nonautomatic position.

Claim 9

A shutter operating mechanism comprising a shutter movable between open and closed position, a movable shutter opening member connected with said shutter and spring biased to move in a shutter opening direction, means for releasably holding said shutter opening member in set position with the shutter in closed position, a movable shutter closing member connected with said shutter and spring biased to move in a shutter closing direction, electrically releasable means for holding said closing member in set position, an exposure time control member settable in a position for automatic shutter operation or in any of a plurality of nonautomatic positions for different exposure times, an aperture control member selectively settable in a position for automatic shutter operation or in any of a plurality of nonautomatic positions for different aperture openings, means for controlling the rate of opening of the shutter upon release of said shutter opening member when said aperture control member is in automatic position, timing circuit means controlling the release of said shutter closing member by said electrically releasable means including a timing switch means operable upon release of said shutter opening member and time delay means operable to release said shutter closing member a selected time period after actuation of said timing switch, said time delay means comprising a photosensitive element, a capacitance and Resistance, and selector means controlled by the settings of said exposure time control member and said aperture control member to control said aperture opening and said time period by said photosensitive element when said exposure time control member and said aperture control member are both set in automatic position, to control said time period jointly by said photosensitive element and the setting of said aperture control member when said exposure time control member is set in automatic position and said aperture control member is set in a selected nonautomatic position, and to control said time period by the setting of said exposure time control member only when each of said control members is set in a selected nonautomatic position.

Claim 10

Shutter operating mechanism according to claim 7, in which said timing circuit means comprises a plurality of resistors of different value and switching means actuated by said exposure time control member to connect said resistors selectively into circuit with said capacitance to vary said time period according to selected nonautomatic settings of said exposure time control member.

Claim 11

Shutter operating mechanism according to claim 7, in which said timing circuit means comprises a plurality of resistors of different values and switching means actuated by said aperture control member to connect said resistors selectively into circuit with said capacitance to vary said time period according to selected settings of said aperture control member.

Claim 12

Shutter operating mechanism according to claim 9, in which said timing circuit means comprises a switch means actuated by said exposure time control member for disconnecting said resistors when said exposure time control member is in a nonautomatic position.