PURPOSE:To set a plurality of stoppage preparation speed, and to enable the rapid stoppage of a sewing-machine needle at a prescribed position by setting the speed of revolution of a variable-speed motor at speed slower than normal sewing speed by means of a control circuit on the basis of speed instruction signals. CONSTITUTION:When the direction of sewing is changed during the revolution of the variable-speed motor 11 at fixed speed, stoppage speed signals 200-202 of 0 are outputted to the FFs 44, 68 of the control circuit 42 from a speed instruction section 12 when an operation pedal 34 is set at a neutral position, the starting signals 212 of 1 and intermediate speed signals 224 are outputted to a drive circuit 48 from the FF44 during a period when stoppage is prepared, and the motor is maintained at predetermined intermediate speed. When low-speed detecting signals 216 are outputted from a low- speed detecting circuit 50 using positional detecting signals 208, 210 from a position detector 41 as input during the period and left-and-right positional detecting signals 206 are outputted from a needle left-and-right position detector 38, reset signals are outputted to the FF44 from an AND gate 64, brake signals 224 are outputted to the drive circuit 48 through a brake one-shot circuit 66, and the motor 11 is stopped.
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