| 摘要 |
PURPOSE:To enable coils to be securely protected against burning by providing a constitution in which a temperature sensor is installed corresponding to a frequently used wire magnet. CONSTITUTION:Wire W of a printing head is attached to leaf springs 1 arranged in a ring form, and during printing, the coil of a magnet M is excited, demagnetizing a magnetic force generated by a permanent magnet 3. This results in the releasing of the leaf spring 1 and the driving of the wire W by the elastic force of the leaf spring. Thus printing is performed by the wire protruding from a wire guide 4. The tip of the wire W is arranged in two-row zigzag fashion. In this wire arrangement, either or both of magnets M7 and M12 for the 7th and 12th wires W7, W12 become hottest. Accordingly a temperature sensor S is provided near a coil for either of or coils for both of the magnets M7, M12 so as to monitor the temperature of these coils. Thus the coils can be protected against burning by stopping the printing or selecting subdivided printing if the coil temperature of the magnets M7, M12 reached a tolerable limit as mentioned above. |
