| 摘要 |
PURPOSE:To provide a simple and inexpensive construction and prevent a head from being overheated owing to a malfunction of a controlling system, by providing a means for detecting a simultaneous driving time of predetermined elements, and stopping the driving of a recording means when the detected time reaches a predetermined value. CONSTITUTION:Three driving signals Dn, Dn+1, Dn+3 for the recording head 4 are inputted to an AND gate 7, and the simultaneous driving time for recording elements corresponding to the three signals is measured by a timer 6. When the detected driving time reaches a predetermine value, a latch 8 outputs a resetting signal to maintain a head controller 2 in a reset state, thereby inhibiting energization of the head 4. With this simple arrangement, the head 4 can be securely prevented from being overheated, even when runaway of the controlling part 1 occurs. |
