PURPOSE: To make it possible to start a vibrating type feeder, stably always, by providing an oscillating section in a control circuit, and by using a feed-back signal from the oscillating section.

CONSTITUTION: A capacitor 7 and a resistance 6 causes a transistor 9 to start oscillation when a power source is energized. The amplitude of a signal at that time is determined by the resistance 6 and the capacitor 7. This signal is delivered to a transistor 27 through a transistor 21 to energize an electromagnet 29. An electrical signal from a feed-back element 30 attached to an vibrator is delivered to a transducer to gradually enlarge the amplitude of the signal under self-control while the level of voltage is monitored. With the repetition of the above-mentioned steps, a desired vibration level is obtained.