| 摘要 |
PURPOSE:To obtain the titled device by dividing N pieces of recording needles, to which recording voltages are applied by one driving circuit, into k pieces of subgroups, inserting an impedance element into said every subgroup, thereby positively preventing the occurrence of abnormal discharges. CONSTITUTION:N pieces (N>=4) of recording needles a1i, a2i... in a large group, which are connected to same recording needle driving circuits A1,..., are divided into k pieces (k>2) of subgroups. A limiting resistor RL is provided in each subgroup. In this connection, capacity Cl between wires is distributed to every limiting resistor RL at every 1/k. The recording capacity at the position of the recording needle a1i is not changed. The value of the limiting resistor RL can be selected as a large value by the amount of the capacity CE which is decreased to 1/k the conventional value. |
