Patent ID: 7367721

Claim:
A bi-stable photographic shutter comprising: a) a driver plate connected to a plurality of shutter blades arranged to open and close a shutter opening responsive respectively to the rotation of the driver plate to one of a to and a fro position; b) a pair of motors each activated to rotate the driver plate to one of the to-and-fro positions; c) a linkage associated with each motor and operatively connecting each motor to the driver plate, a motor and its associated linkage operating to move the driver plate to only one of the to-and-fro positions; d) a fixed member having a cam slot defining spaced stop positions along a cam surface; e) a pivot arm connected to one of the linkages, the pivot arm having an elongated slot; f) the fixed member and pivot arm being disposed one above the other with the pivot arm slot extending transverse the fixed member cam slot; g) a latch pin extending through both slots, the latch pin being biased towards the cam surface and movable along the cam surface to one or the other of the stop positions; and h) the fixed member, pivot arm and latch pin comprising a latch holding the driver plate at one of the to-and-fro positions in the absence of the activation of either motor.