摘要 |
In a camera including an electric motor for advancing the film an increment frame and for cocking and releasing the shutter an interlock mechanism is provided for preventing further motor actuation in the absence of a full frame advance. The interlock mechanism includes a pair of elements for sequentially sensing successively spaced points in the film advancing cycle and for enabling a normally disabled motor energizing network upon the successive actuation of the sensing elements. The sensing elements may be switches actuated by a cam carried by the film take-up shaft and the network, in one form, includes a pair of relays energized by the closure of respective sensing switches, each relay including a hold switch and a controlled switch, the controlled switches being series connected in a motor energizing circuit. In the mechanical counterpart the sensing elements are pawls actuated by the cam, the successive actuation of the pawls releasing an actuating member for closing a switch in series in the motor energizing circuit. Other networks and mechanisms are described.
|