Safety device for the electric shutter of a camera
AssigneeNippon Kogaku K.K.
InventorAkihiko Sato
Life of this patent
Estimating the term…
Abstract
In the electric shutter of a camera having a forward curtain restraining member for restraining a forward shutter curtain in charged condition, a rearward curtain restraining member for restraining a rearward shutter curtain in charged condition with the aid of the attraction of a magnet, and an anticipatory actuation member starting to move prior to the movement of the forward shutter curtain, a safety device is provided with forward curtain control means which is displaceable to a position to release the forward shutter curtain from restraint by utilizing movement of the anticipatory actuation member and which, when the magnet is unattracted, is displaceable to a position to render the forward shutter curtain unreleasable from restraint by utilizing movement of the rearward curtain restraining member.
Claims9
A safety device in a camera's focal plane shutter device which comprises shutter moving means (10, 11, 32, 33) having a forward curtain interlocking portion interlocked with a forward shutter curtain biased in the direction of movement predetermined for shutter release and a rearward curtain interlocking portion interlocked with a rearward shutter curtain biased in the same direction as said forward curtain and said shutter curtains being simultaneously chargeable and separately releasable, forward curtain restraining means (19, 190) disposed for displacement between a first position to restrain said forward curtain interlocking portion and a second position to release said restraint, rearward curtain restraining means (13 - 17, 150) disposed for displacement between a first position to restrain said rearward curtain interlocking portion and a second position to release said restraint, rearward curtain control means (18) for restraining said rearward curtain restraining means in said first position thereof until a predetermined time for providing proper exposure elapses from the start of shutter release operation, and anticipatory actuation means (1 - 6) disposed engageably with said rearward curtain restraining means, said anticipatory actuation means displacing said rearward curtain restraining means to its first position in response to shutter charge operation, and rendering said rearward curtain restraining means displaceable to its second position in response to shutter release operation;
- and
- forward curtain control means disposed between said anticipatory actuation means and said forward curtain restraining means engageably with both of them and with said rearward curtain restraining means,
- said forward curtain control means being effective during shutter charge operation to displace said forward curtain restraining means to said first position in coordination with said anticipatory actuation means,
- said forward curtain control means, when said rearward curtain restraining means is restrained in the first position by said rearward curtain control means, being effective to transmit the movement of said anticipatory actuation means to said forward curtain restraining means during shutter release operation to thereby displace the forward curtain restraining means to said second position, and when said rearward curtain restraining means is in said second position, to render impossible said transmission.
Dependencies are inferred from the claim text.