Method and apparatus for controlling the drive of self-excited vibrating parts feeder

摘要

A drive control method for a self-excited vibrating parts feeder which includes a parts feeder unit and a drive power supply for supplying an electric power of a desired frequency to an electromagnetic vibration generating unit to exert vibrations to the parts feeder unit, the method comprising the steps of: sweeping the voltage of the drive power supply through a predetermined frequency range; detecting a maximum value of a change in the current flowing through an exciting coil of the electromagnetic vibration generating unit while the voltage of the drive power supply is swept; driving the parts feeder at a frequency which generates said maximum value; comparing a current varying within the predetermined frequency range with a predetermined current; and controlling a drive current of the drive power supply so that the varying current and the predetermined current are identical, thereby controlling the vibration amplitude. The parts feeder is always driven at a resonant frequency and with a constant vibration amplitude, without providing a detector mounted on the parts feeder body and without presetting a natural frequency at the time of manufacture of the parts feeder.