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US 9,853,584 B2Granted
Load torque estimation apparatus, image forming apparatus, load torque estimation method and recording medium
AssigneeRicoh Company, Ltd.
InventorTakeo Seki
Life of this patent
Estimating the term…
Abstract
A load torque estimation apparatus includes an acquisition unit configured to acquire a smoothed signal, the smoothed signal being obtained by smoothing a signal indicating a composite current of electric currents flowing in respective phases of an electric motor; and an estimation unit configured to estimate load torque of the electric motor based on the smoothed signal and a rotational speed of the electric motor.
Claims12
A load torque estimation apparatus comprising:
- a memory storing computer-readable instructions;
- and
- a processor configured to execute the computer-readable instructions to,
- store a table of relation information in a storage device, the relation information including approximation formulas defining relations between respective smoothed signals and load torque of an electric motor in association with respective target rotational speeds of the electric motor;
- acquire a smoothed signal obtained by smoothing an inter-shunt resistor voltage signal detected at a shunt resistor arranged in a driver configured to drive the electric motor, the inter-shunt resistor voltage signal indicating a composite current of electric currents flowing in respective phases of the electric motor during driving;
- acquire a rotational speed of the electric motor detected during driving;
- extract, from the table of relation information in the storage device, an approximation formula corresponding to the acquired rotational speed of the electric motor;
- and
- estimate load torque of the electric motor based on inputting the acquired smoothed signal into the extracted approximation formula corresponding to the acquired rotational speed of the electric motor.
6 more elements
A load torque estimation method comprising:
- storing a table of relation information in a storage device, the relation information including approximation formulas defining relations between respective smoothed signals and load torque of an electric motor in association with respective target rotational speeds of the electric motor;
- acquiring a smoothed signal obtained by smoothing an inter-shunt resistor voltage signal detected at a shunt resistor arranged in a driver configured to drive the electric motor, the inter-shunt resistor voltage signal indicating a composite current of electric currents flowing in respective phases of the electric motor during driving;
- acquiring a rotational speed of the electric motor detected during driving;
- extracting, from the table of relation information in the storage device, an approximation formula corresponding to the acquired rotational speed of the electric motor;
- and
- estimating load torque of the electric motor based on inputting the acquired smoothed signal into the extracted approximation formula corresponding to the acquired rotational speed of the electric motor.
3 more elements
A non-transitory computer-readable recording medium storing a program for executing a process of estimating load torque of an electric motor, the program when executed causing a computer to:
- store a table of relation information in a storage device, the relation information including approximation formulas defining relations between respective smoothed signals and load torque of the electric motor in association with respective target rotational speeds of the electric motor;
- acquire a smoothed signal obtained by smoothing an inter-shunt resistor voltage signal detected at a shunt resistor arranged in a driver configured to drive the electric motor, the inter-shunt resistor voltage signal indicating a composite current of electric currents flowing in respective phases of the electric motor during driving;
- acquire a rotational speed of the electric motor detected during driving;
- extract, from the table of relation information in the storage device, an approximation formula corresponding to the acquired rotational speed of the electric motor;
- and
- estimate load torque of the electric motor based on inputting the acquired smoothed signal into the extracted approximation formula corresponding to the acquired rotational speed of the electric motor.
3 more elements
Dependencies are inferred from the claim text.