Non-cocking springless shutter developing two parameter exposure regulation

Claim 2

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: means for sensing the brightness of the scene; a magnetically detented stepper motor having an output drive pinion, said motor being energizable by a select sequence of electrical pulses to rotate said output drive pinion in a step relation therewith; a pair of blade members mounted for displacement with respect to each other between a first position blocking the optical path and other positions unblocking the path and defining an aperture valve through which scene light rays are passed to the camera focal plane, each of said blade members having a primary and secondary opening which when displaced into at least partial coincidence with the corresponding opening of the other blade member respectively define a primary aperture value unblocking the given optical path and a secondary aperture value unblocking said brightness sensing means, each of said blade members having rack extension portions coupled in mutually oppositely meshed relation with said motor drive pinion so that said blade members are simultaneously moveable in opposite directions in accordance with motor operation in a given direction to define progressively changing primary and secondary aperture values; means responsive to the exposure initiating means for generating a first predetermined sequence of electrical pulses to selectively energize said motor in a first directional sense to displace said blades from said first position to unblock the optical path to define progressively enlarging primary aperture values thereby initiating an exposure interval during which scene light is directed to the focal plane and, in response to said brightness sensing means, for subsequently generating a second predetermined sequence of electrical pulses to selectively energize said motor in an opposite directional sense to displace said blades back to said first position thereby terminating the exposure interval.

Claim 3

A photographic exposure control system for a photographic camera configured for scene viewing through the taking lens, the camera having means including a displaceably mounted mirror for directing image-carrying light rays from the scene along a common optical path and then alternately alone either a view path or an exposure path for viewing and film exposure operations respectively, and selectively operable means for initiating an exposure cycle, said exposure cycle initiating means including means for controlling said mirror to change from said view path to said exposure path and back agaIn to said view path, said exposure system comprising: a magnetically detented stepper motor having a rotatable output member, said motor being energizable by a select sequence of electrical pulses to rotate said output member in a step relation therewith; shutter means for blocking and unblocking the optical path and for defining an aperture value through which scene light rays pass along the common optical path, said shutter means including blade means mounted for displacement between a first terminal position blocking the common optical path and a second terminal position unblocking the common path, said blade means defining increasing aperture values during displacement between said first and second terminal positions, said blade means being coupled to said output member and displaceable between said first and said second terminal positions in accordance with rotation thereof, and said blade means being normally in said second terminal position for camera storage and scene viewing purposes; means responsive to the exposure cycle initiating means for generating a first sequence of electrical pulses to selectively energize said motor in one directional sense to display said blade member from said second to said first terminal position to block the common optical path prior to changing from said viewing operation to said exposure operation, for subsequently generatinga second predetermined sequence of electrical pulses to selectively energize generating a motor in a respectively opposite directional sense to unblock the common optical paht so as to initiate an exposure interval during which scene light is directed to the focal plane, for thereafter generating a third predetermined sequence of electrical pulses to again selectively energize said motor in said one directional sense to displace said blades back to said first terminal position to again block the common optical path so as to terminate the exposure interval, and for finally generating a fourth predetermined sequence of electrical pulses to selectively energize said motor in said opposite directional sense to displace said blade means back to said second terminal position for scene viewing purposes.

Claim 4

A photographic exposure control system for a photographic camera configured for scene viewing through the taking lens, the camera having means including a displaceably mounted mirror for directing image-carrying light rays from the scene along a common optical path and then alternately alone either a view path or an exposure path for viewing and film exposure operations respectively, and selectively operable means for initiating an exposure cycle, said exposure cycle initiating means including means for controlling said mirror to change from said view path to said exposure path and back agaIn to said view path, said exposure system comprising: a magnetically detented stepper motor having a rotatable output member, said motor being energizable by a select sequence of electrical pulses to rotate said output member in a step relation therewith; shutter means for blocking and unblocking the optical path and for defining an aperture value through which scene light rays pass along the common optical path, said shutter means including blade means mounted for displacement between a first terminal position blocking the common optical path and a second terminal position unblocking the common path, said blade means defining increasing aperture values during displacement between said first and second terminal positions, said blade means being coupled to said output member and displaceable between said first and said second terminal positions in accordance with rotation thereof, and said blade means being normally in said second terminal position for camera storage and scene viewing purposes; means responsive to the exposure cycle initiating means for generating a first sequence of electrical pulses to selectively energize said motor in one directional sense to display said blade member from said second to said first terminal position to block the common optical path prior to changing from said viewing operation to said exposure operation, for subsequently generatinga second predetermined sequence of electrical pulses to selectively energize generating a motor in a respectively opposite directional sense to unblock the common optical paht so as to initiate an exposure interval during which scene light is directed to the focal plane, for thereafter generating a third predetermined sequence of electrical pulses to again selectively energize said motor in said one directional sense to displace said blades back to said first terminal position to again block the common optical path so as to terminate the exposure interval, and for finally generating a fourth predetermined sequence of electrical pulses to selectively energize said motor in said opposite directional sense to displace said blade means back to said second terminal position for scene viewing purposes.

Claim 5

The system of claim 2 additionally including means responsive to displacement of said blade means to said second terminal position for terminating the energization of said motor in said opposite directional sense so as to minimize power consumption when said blade means is in said second terminal position.

Claim 6

The system of claim 2 wherein a predetermined number of pulses is required for displacing said blade means from said first terminal position to said second terminal position, and said terminating means includes counter means for providing an output signal responsive to said generator producing said predetermined number of pulses in said first directional sense and means responsive to said signal for terminating the flow of pulses to said motor.

Claim 7

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output drive member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between a first terminal position and a second terminal position, said blade means providing changing aperture values through which scene light may pass to the focal plane as said blade means are displaced between said terminal positions, said blade means being coupled to said output drive member and configured for movement therewith; means responsive to the exposure cycle initiating means for generating a sequence of pulses to energiZe said motor in a first directional sense to displace said blade means toward said second terminal position to define a maximum aperture thereat; and means responsive to the generation of a sufficient number of said sequence of pulses sufficient to displace said blade means to its said second terminal position for terminating the energization of said motor to minimize power consumption when said blade means is in its said second terminal position.

Claim 8

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output drive member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between a first terminal position and a second terminal position, said blade means providing changing aperture values through which scene light may pass to the focal plane as said blade means are displaced between said terminal positions, said blade means being coupled to said output drive member and configured for movement therewith; means responsive to the exposure cycle initiating means for generating a sequence of pulses to energiZe said motor in a first directional sense to displace said blade means toward said second terminal position to define a maximum aperture thereat; and means responsive to the generation of a sufficient number of said sequence of pulses sufficient to displace said blade means to its said second terminal position for terminating the energization of said motor to minimize power consumption when said blade means is in its said second terminal position.

Claim 9

The system of claim 5 wherein a predetermined number of pulses is required for displacing said blade means from said first to said second terminal position and said terminating means includes counter means for providing an output signal responsive to said generator producing said predetermined number of pulses in said first directional sense and means responsive to said signal for interrupting the flow of pulses to said motor.

Claim 10

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: means for evaluating the scene being photographed; a magnetically detented stepper motor having a moveable output drive, said motor being energizable by a select sequence of electrical pulses to move said output drive in a step relation therewith; blade means; means for mounting said blade means for displacement between one terminal position blocking passage of light along the optical path and another terminal position wherein it defines an aperture valve through which scene light may pass to the focal plane, said blade means defining progressively changing aperture values as said blade means are displaced from said first terminal position, said blade means being coupled to said output drive member and configured for movement therewith; means responsive to the exposure initiating means for generating a first predetermined sequence of electrical pulses to selectively energize said motor in a first directional sense to displace said blade means from said one terminal position to define progressively changing aperture values thereby initiating an exposure interval during which scene light is directed to the focal plane and, in response to said scene evaluating means, for subsequently generating a second predetermined sequence of electrical pulses to selectively energize said motor in an opposite directional sense to displace said blade means back to said one terminal position thereby terminating the exposure interval, and means for delaying the energization of said motor by said second predetermined sequence of pulses to continue synchronization between said pulses and said motor step relation when said motor is energized in said opposite directional sense.

Claim 11

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: means for evaluating the scene being photographed; a magnetically detented stepper motor having a moveable output drive, said motor being energizable by a select sequence of electrical pulses to move said output drive in a step relation therewith; blade means; means for mounting said blade means for displacement between one terminal position blocking passage of light along the optical path and another terminal position wherein it defines an aperture valve through which scene light may pass to the focal plane, said blade means defining progressively changing aperture values as said blade means are displaced from said first terminal position, said blade means being coupled to said output drive member and configured for movement therewith; means responsive to the exposure initiating means for generating a first predetermined sequence of electrical pulses to selectively energize said motor in a first directional sense to displace said blade means from said one terminal position to define progressively changing aperture values thereby initiating an exposure interval during which scene light is directed to the focal plane and, in response to said scene evaluating means, for subsequently generating a second predetermined sequence of electrical pulses to selectively energize said motor in an opposite directional sense to displace said blade means back to said one terminal position thereby terminating the exposure interval, and means for delaying the energization of said motor by said second predetermined sequence of pulses to continue synchronization between said pulses and said motor step relation when said motor is energized in said opposite directional sense.

Claim 12

The system of claim 7 wherein said generating means includes a clock network providing a train of pulses of given pulse length and said delay is substantially equal to said given pulse length.

Claim 13

The system of claim 7 wherein said delay is in the range 1 to 1 1/2 milliseconds.

Claim 14

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output drive member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between one terminal position wherein it will preclude passage of scene light along the given optical path and at least another position wherein it defines an aperture vAlue through which scene light may pass to the focal plane, said blade means being coupled to said output drive member and configured for movement therewith; and means responsive to the exposure initiating means for generating a sequence of electrical pulses at a first average frequency to selectively energize said motor in a first directional sense effecting the displacement of said blade means at a first average rate from said one position to initiate the opening phase of an exposure interval during which scene light is directed to the focal plane and, in correlation with an evaluation of the scene being photographed, for subsequently generating a sequence of electrical pulses at a second average frequency to selectively energize said motor a second average rate in an opposite directional sense effecting the displacement of said blade means back to said one position thereby defining the closing phase of the exposure interval.

Claim 15

A photographic exposure control system for a camera, the camera having means for mounting photographic film material at a given focal plane, a lens for directing image-carrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output drive member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between one terminal position wherein it will preclude passage of scene light along the given optical path and at least another position wherein it defines an aperture vAlue through which scene light may pass to the focal plane, said blade means being coupled to said output drive member and configured for movement therewith; and means responsive to the exposure initiating means for generating a sequence of electrical pulses at a first average frequency to selectively energize said motor in a first directional sense effecting the displacement of said blade means at a first average rate from said one position to initiate the opening phase of an exposure interval during which scene light is directed to the focal plane and, in correlation with an evaluation of the scene being photographed, for subsequently generating a sequence of electrical pulses at a second average frequency to selectively energize said motor a second average rate in an opposite directional sense effecting the displacement of said blade means back to said one position thereby defining the closing phase of the exposure interval.

Claim 16

The system of claim 10 wherein said second frequency is substantially faster than said first frequency so as to define a faster closing than opening phase.

Claim 17

A photographic exposure control system for a camera, the camera having means for mounting photographic material at a given focal plane, means for directing imagecarrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between a position blocking the optical path and another position unblocking the optical path, said blade means providing changing aperture values through which scene light may pass to the focal plane as said blade means are displaced from said blocking position, said blade means being coupled to said output member and configured for movement therewith; and means responsive to the exposure initiating means for generating a first predetermined sequence of electrical pulses to selectively energize said motor in a first directional sense to displace said blade means from said blocking position toward said other position to initiate an exposure interval during which scene light is directed to the focal plane and for then generating a second predetermined sequence of electrical pulses to selectively energize said motor in an opposite directional sense to displace said blade means back to said blocking position thereby terminating the exposure interval.

Claim 18

A photographic exposure control system for a camera, the camera having means for mounting photographic material at a given focal plane, means for directing imagecarrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between a position blocking the optical path and another position unblocking the optical path, said blade means providing changing aperture values through which scene light may pass to the focal plane as said blade means are displaced from said blocking position, said blade means being coupled to said output member and configured for movement therewith; and means responsive to the exposure initiating means for generating a first predetermined sequence of electrical pulses to selectively energize said motor in a first directional sense to displace said blade means from said blocking position toward said other position to initiate an exposure interval during which scene light is directed to the focal plane and for then generating a second predetermined sequence of electrical pulses to selectively energize said motor in an opposite directional sense to displace said blade means back to said blocking position thereby terminating the exposure interval.

Claim 19

The system of claim 12 wherein said stepper motor output member includes a drive pinion, said blade means includes a pair of blade members, each of said blade members having an opening therein configured when displaced into at least partial coincidence with the opening of the other blade member for defining an aperture value unblocking the optical path, and each of said blade members having a rack extension coupled in mutually oppositely meshed relation with said motor drive pinion so that said blade members are simultaneously moveable in opposite directions in accordance with motor operation to define changing aperture values.

Claim 22

The method of claim 14 wherein said series of pulses is generated as said shutter is actuated.

Claim 23

The method of claim 14 wherein said utilizing step includes applying said pulses in a first sequence to drive said motor in a first directional sense so as to actuate said shutter arrangement to define progressively enlarging apertures and then applying said pulses in a second sequence to drive said motor in an opposite directional sense to define progressively decreasing aperture values.

Claim 24

A photographic exposure control system for a camera, the camera having means for mounting photographic material at a given focal plane, means for directing imagecarrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between a position blocking the optical path and another position unblocking the optical path, said blade means providing changing aperture values through which scene light may pass to the focal plane as said blade means are displaced from said blocking position, said other position defining the maximum said aperture value, said blade means being coupled to said output member of said magnetically detented stepper motor and configured for movement therewith; and means responsive to the exposure initiating means for generating a sequence of electrical pulses to selectively energize said magnetically detented stepper motor to initiate an exposure interval related to scene brightness during which scene light is directed to the focal plane and to displace said blade means from said blocking position toward said other position, and for then generating a sequence of electrical pulses to selectively energize said magnetically detented stepper motor to effect a further displacement of said blade means to cause said blade means to again preclude scene light from passing to the focal plane thereby terminating said exposure interval.

Claim 25

A photographic exposure control system for a camera, the camera having means for mounting photographic material at a given focal plane, means for directing imagecarrying rays from a scene along a given optical path to the camera focal plane, and selectively operable means for initiating an exposure cycle, said system comprising: a magnetically detented stepper motor having a moveable output member, said motor being energizable by a select sequence of electrical pulses to move said output member in a step relation therewith; blade means; means for mounting said blade means for displacement between a position blocking the optical path and another position unblocking the optical path, said blade means providing changing aperture values through which scene light may pass to the focal plane as said blade means are displaced from said blocking position, said other position defining the maximum said aperture value, said blade means being coupled to said output member of said magnetically detented stepper motor and configured for movement therewith; and means responsive to the exposure initiating means for generating a sequence of electrical pulses to selectively energize said magnetically detented stepper motor to initiate an exposure interval related to scene brightness during which scene light is directed to the focal plane and to displace said blade means from said blocking position toward said other position, and for then generating a sequence of electrical pulses to selectively energize said magnetically detented stepper motor to effect a further displacement of said blade means to cause said blade means to again preclude scene light from passing to the focal plane thereby terminating said exposure interval.