| 摘要 |
PURPOSE:To decrease recording noises and to improve the recording speed and character quality by providing means, which individually detect the attachments and removals of a plurality of recording heads, and means, which control a driving signal to a driving source for a carriage in response to the outputs of the above described means. CONSTITUTION:Detecting switches 3h-1 and 3h-2, which individually detect the presence or absence of the mounting of each ink head, are provided at ink-head mounting parts 3i-1 and 3i-2 of a carriage 3. When one ink head is mounted on the carriage 3, the pulse width of a driving signal is set in short width by the amount corresponding to the reduction in inertial load of the carriage 3. In an accelerating region (a), the pulse width of phi1-phi4 are set 5t 4t 3t 2t. In a constant speed region (b), the pulse width are set at 2t. In the decelerating region (c), the pulse widths are set 2t 3t 4t 5t. In this way excitation is performed. Thus, each conducting width is shortened by 1t, and the rotating torque of a step motor 13 is decreased. The transient characteristic of the running of the carriage is made to be the same as the characteristic when the carriages 3 are two. In this way, the printing noises are decreased, and the printing speed and the quality of the recorded characters are improved. |
