| 摘要 |
PURPOSE: To realize the lightweight and space reduction of a sewing machine by discriminating disconnection on the basis of an inverse start power detecting signal from a detection circuit arranged between the drive circuit of a stepping motor and the stepping motor, stopping the action of the drive circuit when disconnection is decided, and issuing a warning. CONSTITUTION: Whether or not an inverse start power detecting circuit 13 is actuated is discriminated. That is, when a stepping motor 8 is disconnected, an energy dissolving electric current is run, and energy at this time (inverse start power) is relieved to an energy absorption circuit 14, and at the same time, a signal is outputted to a motor control circuit 10. The motor control circuit 10 discriminates whether it is a disconnection or a noise. When disconnection is discriminated, a magnetizing action stop command is issued to a motor drive circuit 9, and the action of the motor drive circuit 9 is stopped. Simultaneously, an indication control circuit 15 displays disconnection warning indication on a display device 6. |
