| 摘要 |
An apparatus for measuring a remaining amount of a bobbin thread wound on a bobbin accommodated in a shuttle of a sewing machine, including a measurement bar displaceable along a displacement path from outside the shuttle toward an axis line of the bobbin inside the shuttle, a driver which displaces the measurement bar along the displacement path so that a free end of the bar contacts the outer surface of a roll of bobbin thread wound on the bobbin, a sensor which detects the displacement of the measurement bar and generates a displacement signal representative of continuous change in displacement amount of the bar, a signal-characteristic determining and storing device which determines a characteristic of the displacement signal based on respective values of the displacement signal when the measurement bar is located at a plurality of reference positions on the displacement path, and stores data indicative of the determined signal characteristic, and a remaining-amount determining device which determines the remaining amount of the bobbin thread left on the bobbin, based on the stored signal characteristic and a value of the displacement signal when the free end of the measurement bar contacts the outer surface of the roll of bobbin thread.
|
