Lens driving and shutter opening and closing device for a camera

摘要

Disclosed is a lens driving and shutter opening and closing device for a camera, which includes a pulse motor adapted to rotate an output member by an angle proportional to the number of pulses of a pulse train supplied thereto and increase an output torque thereof when a pulse rate of the pulse train is reduced, a member coupled to the output member of the pulse motor through a speed-reduction gear for driving a lens and opening and closing shutter blades selectively when the pulse motor rotates, and a control mechanism for supplying a first pulse train having a first pulse rate to the pulse motor for driving the lens and supplying a second pulse train having a second pulse rate to the pulse motor for opening and closing the shutter blades, the first pulse rate being smaller than the second pulse rate in order that the pulse motor produces an output torque required for driving the lens which is larger than that required for opening and closing the shutter blades and rotates at a speed required for opening and closing the shutter blades faster than that required for driving the lens.