| 摘要 |
PURPOSE:To facilitate the regulating work of an operating position of a pedal for a sewing machine by comparing a voltage varying in response to the operating amount of the pedal with a set voltage by an external operation, thereby detecting the operating position of the pedal. CONSTITUTION:When a pedal 5 is pressed clockwise from the middle position, the resistance value of a variable resistor VR1 becomes larger, and when the (-) side voltage of a comparing circuit M1 becomes lower than the (+) side voltage, a motor 2 is started in normal rotation. When the pedal 5 is pressed counterclockwise from the middle position, the resistance value of the resistor VR1 becomes small, and when the (-) side voltage of a comparing circuit M2 becomes higher than the (+) side voltage, the motor 2 is started in reverse side. Thus, the pedal operation detecting position can be regulated by the adjustments of the resistors VR2, VR3. |
