摘要 |
<p>A device for automatically changing the polarity of a direct current supply source for use in a cataphoresis apparatus comprises a switch for changing the polarity of migration current, a device for generating a functional signal in response to a detection of the finish or the beginning of the migration current, a signal processing device connected to the functional signal generator for processing the functional signal to drive the polarity change switch and a polarity changing device connected between the signal processing device and the polarity change switch for instructing polarity change of the migration current to the polarity change switch and for memorizing the changed polarity of the migration current in spite of switching on or off of a power supply source. The polarity changing device always changes the polarity of the migration current to a polarity opposite to the just before polarity every detection of the finishing or the beginning of the migration current.</p> |