Abstract: A signal conversion device includes a first signal input terminal, a second signal input terminal, and a detector. A first AC signal is supplied to the first signal input terminal from a signal source. The second signal input terminal is supplied with an in-phase signal that is in phase with the first AC signal and an opposite-phase signal that is opposite in phase with the first AC signal. The second signal input terminal is supplied with a second AC signal whose phase has been switched by a switchover between the in-phase signal and the opposite-phase signal from the signal source. The detector detects, using the supplied first AC signal, whether the supplied second AC signal is the in-phase signal or the opposite-phase signal.

Abstract: A motor unit includes a motor, a controller that outputs a pulse signal, a driver that supplies a drive current to the motor based on the pulse signal, and a detector that determines an actual rotation number of the motor. The controller includes calculators that calculate control values of a rotation number of the motor, and control stages. The controller also includes a pulse generator that selects one of the control values calculated by the calculators to generate the pulse signal based on the control value selected, at each of the control stages.

Abstract: A signal conversion device includes a first signal input terminal, a second signal input terminal, and a detector. A first AC signal is supplied to the first signal input terminal from a signal source. The second signal input terminal is supplied with an in-phase signal that is in phase with the first AC signal and an opposite-phase signal that is opposite in phase with the first AC signal. The second signal input terminal is supplied with a second AC signal whose phase has been switched by a switchover between the in-phase signal and the opposite-phase signal from the signal source. The detector detects, using the supplied first AC signal, whether the supplied second AC signal is the in-phase signal or the opposite-phase signal.

Abstract: A motor unit includes a motor, a controller that outputs a pulse signal, a driver that supplies a drive current to the motor based on the pulse signal, and a detector that determines an actual rotation number of the motor. The controller includes calculators that calculate control values of a rotation number of the motor, and control stages. The controller also includes a pulse generator that selects one of the control values calculated by the calculators to generate the pulse signal based on the control value selected, at each of the control stages.

Abstract: A motor driving device includes an analog to digital conversion circuit to which a speed command voltage instructing a rotation speed of a motor is inputted, and a microcomputer configured and programmed to generate a speed command having a pulse width which is changed according to the speed command voltage based on an output signal of the analog to digital conversion circuit. Further, the motor driving device includes a signal isolator configured to transmit the speed command between an input and an output while providing isolation between the input and the output, and a drive circuit configured to generate a driving signal in response to the speed command outputted from the signal isolator and to change the rotation speed of the motor.

Abstract: A motor driving system that changes a rotation speed of a motor pursuant to a speed command includes a main device including a drive circuit configured to drive the motor, an input device configured to input the speed command to the drive circuit, and a signal insulating unit configured to insulate the input device from the main device and to transmit the speed command from the input device to the drive circuit of the main device.

Abstract: A motor driving device includes an analog to digital conversion circuit to which a speed command voltage instructing a rotation speed of a motor is inputted, and a microcomputer configured and programmed to generate a speed command having a pulse width which is changed according to the speed command voltage based on an output signal of the analog to digital conversion circuit. Further, the motor driving device includes a signal isolator configured to transmit the speed command between an input and an output while providing isolation between the input and the output, and a drive circuit configured to generate a driving signal in response to the speed command outputted from the signal isolator and to change the rotation speed of the motor.

Abstract: A motor driving system that changes a rotation speed of a motor pursuant to a speed command includes a main device including a drive circuit configured to drive the motor, an input device configured to input the speed command to the drive circuit, and a signal insulating unit configured to insulate the input device from the main device and to transmit the speed command from the input device to the drive circuit of the main device.