DC ionizer using opposed φ-type corona electrodes for high speed charge elimination

A corona type ionizer is a device that supplies air flow including positive and negative corona ions for the elimination of electrostatic charges on a charged target. DC ionizers placed close to the charged target are proposed to shorten the charge elimination time and decrease the remaining voltage. The ionizer is composed of a grounded mesh electrode and opposed positive and negative needle electrodes. The opposed φ-type electrodes are also tested to improve the performance. A strong electric field can be formed between the grounded mesh and the charged target; therefore, the ion drag force due to the electric field become dominant and plays an important role in charge elimination with this technique. A charge elimination model using a simplified charge elimination current is also proposed to evaluate the performance of the ionizers. The charge elimination performance of the ionizer using opposed φ-type electrodes was much better than that using opposed needle electrodes, due to the increase in the positive and negative charge density, which increases elimination of the target charge.