| 摘要 |
<p>Method and arrangement for controlling the print current in metal paperprinters For record carriers with a greatly varying thickness of the metal layer, the burn out process is effected dynamically with respect to the current strength. During the starting phase up to the beginning of the actual arcing phase a relatively high current is applied which is sufficient to burn out even thick metal layers. As burning out proceeds, the print current, after a particular arc voltage has been reached, is reduced in a short time, maintaining the are and avoiding an undesirable burning out which would increase the print spot. For thinner metal layers the burn out current is correspondingly lower. The maximum burn out current is automatically adjusted to the thickness of the metal layer by measuring the arc voltage between electrode and metal surface of the record carrier. Suitable arrangements for controlling the burn out current are characterized by an (are) voltage-controlled current control circuit.</p> |
