Shutter latch arrangement releasable through shutter blade actuation and resettable through film advancement

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• and
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced responsive to said actuation of said drive means to effect its release of said blade mechanism, to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuating means including manually actuable means for initially actuating said drive means together with means responsive to said latch means releasing said blade member for maintaining the actuation of said drive means throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means, wherein:
• said mounting means mounts said blade mechanism for movement to a third arrangement in addition to said arrangement wherein it is retainable by said latch means and its said other arrangement, its said third arrangement being an arrangement wherein said blade mechanism is further displaced away from its said other arrangement than when in its said arrangement wherein it is retainable by said latch means and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement;
• and said drive means includes an electrically energizable solenoid for displacing said blade mechanism from its said other arrangement toward its said third arrangement together with resilient means for yieldably urging said blade mechanism toward its said other arrangement;
• said actuable means additionally includes switch means connectable between a source of electrical energy and said solenoid to initiate the electrical energization of said solenoid to displace said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement in which said blade mechanism is released by displacement of said latch means;
• and said means for maintaining the actuation of said drive means subsequent to the manual deactuation of said manually actuable means includes means operatively associated with said latch means and switch means and responsive to displacement of said latch means for rendering said switch means conductive throughout at least the remainder of the exposure cycle.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• and
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced reponsive to said actuation of said drive means to effect its release of said blade mechanism, to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuating means including manually actuable means for initially actuating said drive means together with means responsive to said latch means releasing said blade member for maintaining the actuation of said drive means throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means wherein:
• said mounting means mounts said blade mechanism for movement to a third arrangement in addition to said arrangement wherein it is retainable by said latch means and its said other arrangement, its said third arrangement being an arrangement wherein said blade mechanism is further displaced away from its said other arrangement than when in its said arrangement wherein it is retainable by said latch means and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement;
• said drive means includes electrically energizable means for displacing said blade mechanism from its said other arrangement toward its said third arrangement together with resilient means for yieldably urging said blade mechanism toward its said other arrangement;
• said manually actuable means includes a pushbutton type switch connectable between a source of electrical energy and said electrically energizable drive means to initiate the electrical energization of said drive means to displace said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement in which said blade mechanism is released by displacement of said latch means;
• and said means for maintaining the actuation of said drive means subsequent to the manual deactuation of said pushbutton switch includes at least a first switch in a normally nonconductive condition in parallel connection with respect to said pushbutton switch, said first switch coming into operative association with said latch means upon the displacement thereof so as to be conductive throughout at least the remainder of the exposure cycle.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• and
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced responsive to said actuation of said drive means to effect its release of said blade mechanism, to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuating means including manually actuable means for initially actuating said drive means together with means responsive to said latch means releasing said blade member for maintaining the actuation of said drive means throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means wherein:
• its said other of said arrangements of said blade mechanism is said unblocking arrangement and said mounting means mounts said blade mechanism for movement between two blocking arrangements, the first of said blocking arrangements being its said arrangement wherein it is retainable by said latch means and the second of said blocking arrangements being an arrangement wherein said blade mechanism is further displaced away from its said unblocking arrangement than when in its said first blocking arrangement and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said first blocking arrangement to its said second blocking arrangement, said drive means includes electrically energizable means for displacing said blade mechanism from its said unblocking arrangement towards its said two blocking arrangements together with resilient means for yieldably urging said blade mechanism toward its said other arrangement;
• said manually actuable means includes a pushbutton type switch connectable between a source of electrical energy and said electrically energizable means to accommodate the electrical energization of said drive means to displace said blade mechanism from its said first blocking arrangement to its said second blocking arrangement in which said blade mechanism is released by displacement of said latch means;
• and said means for maintaining the actuation of said drive means subsequent to the manual deactuation of said pushbutton switch includes at least a first switch in a normally nonconductive condition in parallel connection with respect to said pushbutton switch, said first switch coming into operative association with said latch means upon the displacement thereof so as to be conductive throughout at least the remainder of the exposure cycle.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced responsive to said actuation of said drive means to effect its release of said blade mechanism, to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuating means including manually actuable means for initially actuating said drive means together with means responsive to said latch means releasing said blade member for maintaining the actuation of said drive means throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means;
• means for advancing the given photographic material from the given focal plane subsequent to the exposure thereof during the exposure cycle;
• and
• means responsive to operation of said advancing means for positioning said latching means to accommodate return of said blade mechanism back to its said arrangement wherein it is retainable by said latch;
• wherein said means for advancing the given photographic material includes:
• a wheel member having at least one cam surface in fixed connection thereto, means for rotatably mounting said wheel with respect to the camera, means for rotatably driving said wheel, and means in operative association with said wheel for displaceably engaging the given photographic material upon the rotation of said wheel;
• and wherein said means for positioning said latching means to accommodate return of said blade mechanism back to its arrangement wherein it is retainable by said latch means includes:
• means operatively associated with said wheel and latch means and responsive to engagement with said cam surface of said wheel for displacing said latch means into position accommodating the return of said blade mechanism back to its said arrangement wherein it is retainable by said latch means.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to a predetermined displacement of said blade mechanism resulting from actuation of said drive means to effect its release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle;
• means for advancing the given photographic material from the given focal plane subsequent to the exposure thereof during the exposure cycle;
• and
• means responsive to operation of said advancing means for positioning said latch means to accommodate return of said blade mechanism back into its said arrangement wherein it is retainable by said latch means.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to said actuation of said drive means to effect its release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle;
• means for advancing the given photographic material from the given focal plane subsequent to the exposure thereof during the exposure cycle;
• and
• means responsive to operation of said advancing means for positioning said latch means to accommodate return of said blade mechanism back into its said arrangement wherein it is retainable by said latch means wherein said mounting means mounts said blade mechanism for movement to a third arrangement in addition to its said arrangement wherein it is retainable by said latch means and its said other arrangement, its said third arrangement being an arrangement wherein said blade mechanism is further displaced away from its said other arrangement, than when in its said arrangement wherein it is retainable by said latch means and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to said actuation of said drive means to effect its release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle;
• means for advancing the given photographic material from the given focal plane subsequent to the exposure thereof during the exposure cycle;
• and
• means responsive to operation of said advancing means for positioning said latch means to accommodate return of said blade mechanism back into its said arrangement wherein it is retainable by said latch means wherein its said other of said arrangements of said blade mechanism is said unblocking arrangement, said mounting means mounts said blade mechanism for movement between two blocking arrangements, the first of said blocking arrangements being its said arrangement wherein it is retainable by said latch means and the second of said blocking arrangements being an arrangement wherein said blade mechanism is further displaced away from its said unblocking arrangement than when in its said first blocking arrangement and the release of said blade mechanism by said latching means is responsive to a displacement of said blade mechanism from its said first blocking arrangement to its said second blocking arrangement.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to said actuation of said drive means to effect its release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle;
• means for advancing the given photographic material from the given focal plane subsequent to the exposure thereof during the exposure cycle;
• and
• means responsive to operation of said advancing means for positioning said latch means to accommodate return of said blade mechanism back into its said arrangement wherein it is retainable by said latch means wherein said drive means for said blade mechanism includes electrically energizable means for displacing said blade mechanism in a given direction;
• said photographic material advancing means includes an electrically energizable motor;
• said actuating means includes a first manually actuable switch connectable at least between a source of electrical energy and said electrically energizable blade drive means to initiate the electrical energization of said blade drive means effecting the release of said blade mechanism and further including an electrically energizable control circuit for thereafter selectively actuating and deactuating said blade mechanism drive means and motor at predetermined times during the exposure and advancement of the given photographic material together with at least one switch in a normally nonconductive condition for connecting said control circuit to the source of electrical energy;
• and said means for positioning said latch means to accommodate return of said blade mechanism back to its said arrangement wherein it is retainable by said latch means includes an actuator arm member together with means for mounting said actuator arm member for rotation with respect to the camera, said actuator arm member being resiliently biased into engagement with said latch means to rotatably displace said latch means into relasing said blade mechanism responsive to said drive means actuation while also rotating into engagement with said one switch to render said one switch conductive, said actuator arm thereafter being rotated against its said direction of resilient bias responsive to operation of said advancing means to render said one switch nonconductive and facilitate rotatable displacement of said latch means back to its said arrangement wherein it is retainable by said latch means.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light of the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to a predetermined displacement of said mechanism resulting from actuation of said drive means to effect its normal release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle and said blade mechanism also being responsive to a sudden shocking thereof for movement from its said arrangement wherein it is retainable by said latch means to another of its said arrangements;
• and
• shock stabilizing means responsive to said shocking of said blade mechanism not resulting from said actuation of said drive means for prohibiting the release of said blade mechanism by said latch means.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to said actuation of said drive means to effect its normal release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle and said blade mechanism also being responsive to a sudden shocking thereof for movement from its said arrangement wherein it is retainable by said latch means to another of its said arrangements;
• and
• shock stabilizing means responsive to said shocking of said blade mechanism not resulting from said actuation of said drive means for prohibiting the release of said blade mechanism by said latch means wherein:
• said mounting means mounts said blade mechanism for movement to a third arrangement in addition to said arrangement wherein it is retainable by said latch means and said other arrangement, its said third arrangement having an arrangement wherein said blade mechanism is further displaced away from its said other arrangement than when in its said arrangement wherein it is retainable by said latch means and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement;
• and said shock stabilizing means includes an inertial member, together with means for mounting the inertial member for limited displacement with respect to the camera, said inertial member having a portion thereof normally disposed for engagement with said blade mechanism upon said shocking of said blade mechanism, said shocking of said blade mechanism operating to cause said inertial member to move away from its said normally disposed position and thereafter rebound back into its said normally disposed position to engage said blade mechanism in said arrangement wherein it is retainable by said latch means when said drive means remains unactuated.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to said actuation of said drive means to effect its normal release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle and said blade mechanism also being responsive to a sudden shocking thereof for movement from its said arrangement wherein it is retainable by said latch means to another of its said arrangements;
• and
• shock stabilizing means responsive to said shocking of said blade mechanism not resulting from said actuation of said drive means for prohibiting the release of said blade mechanism by said latch means wherein:
• said other of said arrangements of said blade mechanism is said unblocking arrangement;
• said mounting means mounts said blade mechanism for movement between two blocking arrangements, the first of said blocking arrangements being said arrangement wherein it is retainable by said latch means and the second of said blocking arrangements being an arrangement wherein said blade mechanism is further displaced away from its said unblocking arrangement than when in its said first blocking arrangement and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said first blocking arrangement to its said second blocking arrangement;
• and said shock stabilizing means includes an inertial member, together with means for mounting the inertial member for limited displacement with respect to the camera, said inertial member having a portion thereof normally disposed for engagement with said blade mechanism upon said shocking of said blade mechanism, said shocking of said blade mechanism operating to cause said inertial member to move away from its normally disposed position and thereafter rebound back into its said normally disposed position to engage said blade mechanism in said first blocking arrangement when said drive means remains actuated.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means at least in part electrically energizable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• and
• actuable means for connecting said drive means to a source of electrical energy to effect the displacement of said blade mechanism for its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced responsive to said connection of said drive means to the source of electrical energy to effect its release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuable means including manually actuable means for initially connecting said drive means to a source of electrical energy together with means responsive to said latch means releasing said blade member for maintaining the connection of said drive means to the source of electrical energy throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means.

A photographic camera having means for mounting photographic film material at a given focal said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured for displacement responsive to a predetermined displacement of said blade mechanism resulting from actuation of said drive means to effect its release of said blade mechanism to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, and including means for alternatively effecting said displacement in response to displacement of said blade mechanism from said unblocking arrangement toward said at least one blocking arrangement;
• means for advancing the given photographic material from the given focal plane subsequent to the exposure thereof during the exposure cycle;
• and
• means responsive to operation of said advancing means for positioning said latch means to accommodate return of said blade mechanism back into its said arrangement wherein it is retainable by said latch means.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arragement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means at least in part electrically energizable and actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• and
• means independent of said latch means and at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced responsive to said actuation of said drive means to effect its release of said blade mechanism, to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuating means including manually actuable means for initially actuating said drive means together with means responsive to said latch means releasing said blade member for maintaining the actuation of said drive means throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means.

A photographic camera having means for mounting photographic film material at a given focal plane, said camera comprising:

• a blade mechanism;
• means for mounting said blade mechanism for displacement between at least one blocking arrangement precluding transmission of scene light to the focal plane and an unblocking arrangement defining at least one aperture value structured for transmission of scene light to the focal plane;
• drive means actuable for displacing said blade mechanism between its said arrangements;
• latch means for initially retaining said blade mechanism in one of its said arrangements;
• and
• means at least in part electrically energizable for actuating said drive means to effect the displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to another of its said arrangements and then back to its said arrangement wherein it is retainable by said latch means to define an exposure cycle of said blade mechanism, said latch means being structured to be displaced responsive to said actuation of said drive means to effect its release of said blade mechanism, to facilitate the movement of said blade mechanism under the influence of said drive means to define said exposure cycle, said actuating means including manually actuable means for initially actuating said drive means together with means responsive to said latch means releasing said blade member for maintaining the actuation of said drive means throughout the remainder of the exposure cycle subsequent to the manual deactuation of said manually actuable means, wherein said mounting means also mounts said blade mechanism for movement to a third arrangement in addition to said arrangement wherein it is retainable by said latch means and its said other arrangement, its said third arrangement being an arrangement wherein said blade mechanism is further displaced away from its said other arrangement than when in its said arrangement wherein it is retainable by said latch means and the release of said blade mechanism by said latch means is responsive to a displacement of said blade mechanism from its said arrangement wherein it is retainable by said latch means to its said third arrangement.