Abstract: The present invention relates to an improved gyro-type manually operated dynamo mechanism applied to appliances consuming limited momentary power. Energy is stored by stressing a spring which, when released, keeps in mechanical connection with a train of acceleration gears terminating in a relatively heavy flywheel when the stressed spring is released to resume its unstressed state, and disconnects therewith when the spring reaches unstressed condition and allow the flywheel to rotate freely, thereby enhancing the exploitation of the energy stored in the flywheel in the form of inertia to produce the requisite electricity to sound the buzzer.