Motor control and drive circuit
First Claim
1. A motor control and drive circuit for rotating a motor, which applies a motor drive current to a coil of the motor, generates a detection signal indicating a rotating condition of the motor from a voltage generated at the coil, generates a drive signal whose waveform corresponds to the detection signal, and outputs the drive signal as the motor drive current by amplifying the waveform of the drive signal, comprising:
- a sensing circuit for sensing the difference between a drive signal applied to a motor coil and a neutral point to produce a detection signal;
a drive signal generation circuit for generating a signal, in accordance with the detection signal, whose waveform has a cycle following a cycle of the detection signal and has an inclination portion having a predetermined inclination, and outputting the generated signal as the drive signal; and
a circuit for receiving the outputted drive signal, detecting at least one of a peak level and amplitude value of the drive signal, comparing the detected value with a predetermined reference value, and generating a signal for reactivating the motor when an absolute value of the peak value is smaller than the reference value.
1 Assignment
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Accused Products
Abstract
A peak level of a drive signal U having predetermined inclination portions is detected, and a detection signal Q is outputted when the peak level has not reached a predetermined value. Since the detection signal Q indicates the out-of-step condition of the motor, the use of the detection signal Q allows reactivation or the like to be triggered easily in a simple circuit. Therefore, the rotation of the motor can be activated by reactivation or the like without strict adjustment but with only a practically adequate adjustment.
13 Citations
5 Claims
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1. A motor control and drive circuit for rotating a motor, which applies a motor drive current to a coil of the motor, generates a detection signal indicating a rotating condition of the motor from a voltage generated at the coil, generates a drive signal whose waveform corresponds to the detection signal, and outputs the drive signal as the motor drive current by amplifying the waveform of the drive signal, comprising:
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a sensing circuit for sensing the difference between a drive signal applied to a motor coil and a neutral point to produce a detection signal; a drive signal generation circuit for generating a signal, in accordance with the detection signal, whose waveform has a cycle following a cycle of the detection signal and has an inclination portion having a predetermined inclination, and outputting the generated signal as the drive signal; and a circuit for receiving the outputted drive signal, detecting at least one of a peak level and amplitude value of the drive signal, comparing the detected value with a predetermined reference value, and generating a signal for reactivating the motor when an absolute value of the peak value is smaller than the reference value.
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2. A motor controlling device for controlling a rotation of a motor, comprising:
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detecting means for detecting a rotating condition of said motor; motor driving means for generating a motor driving signal according to the detection signal of said detecting means; peak detection means for detecting a peak level of the motor driving signal and for generating a failure signal when the peak level is smaller than a predetermined voltage; and starter reactivation means for resetting and reactivating said motor driving means in response to said failure signal. - View Dependent Claims (3, 4)
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5. A motor control and drive circuit for generating, according to a first detection signal corresponding to a voltage to be generated at a coil of a motor, a drive signal having a signal waveform for determining a current waveform to be applied to the coil, comprising:
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a sensing circuit for sensing the difference between a drive signal applied to a motor coil and a neutral point to produce a detection signal; a sawtooth wave generation circuit for receiving a signal having the same cycle as and being synchronous with the detection signal and generating a sawtooth wave signal, the sawtooth wave signal being brought to a predetermined initial value at a timing of inverting the received signal;
a peak detection circuit for receiving the sawtooth wave signal and detecting a peak value thereof; and
a circuit for receiving the detected peak value and comparing the peak value with a predetermined reference value, so that a signal for reactivating the motor can be generated when an absolute value of the peak value is smaller than the reference value.
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Specification