摘要 |
<p>In a sewing machine having a machine controller for controlling the rotational speed of the machine and a needle amplitude, adjusting device, a machine control power source switch is provided which is manipulated to produce a switch-over signal, which is identified in a predetermined lapse of time to avoid an erroneous operation of the sewing machine which may be caused by a simple switching operation of the power source switch. The power source switch is released to return to the initial position and is operated again to switch back the machine controller to the function controlling the rotation speed of the sewing machine. The change-over circuit with transmission gates is provided in the sewing machine, which is electrically connected to the amplitude adjusting device and the machine controller and to the control power source switch, respectively.</p> |