| 摘要 |
PURPOSE:To prevent excessive heat accumulator by estimating the accumulated heat of the thermal head due to recording energization in advance and controlling the amount of heating of heating elements by feed-forward control. CONSTITUTION:If pulses A do not arrive during the period of constant period pulses B, i.e., if the time interval of a recording command becomes long, the output is inverted from 0 to 1, and the output of pulses to a gate circuit 72 is commanded to a timer 71a. During the period the pulses A are coming during the period of the cnstant pulses B, i.e., the time interval of the recording command is short, the output is 0, and the output of the pulses from a specified timer is commanded to the gate circuit 72. Thus the current conducting time of 1 pulse in the continuous recording and intermittent recording is determined, and the current conduction control during which excessive temperature rise in heating elements due to the increase in the accumulated heat in the thermal head is performed. Since this is the feed forward control by which current conducting energy is controlled based on the recording or non-recording state immediately before, the excessive heating of the thermal head and the heating elements can be prevented beforehand. |
