Koyo Electronics Industries Co. Ltd. Patent applications |
Patent application number | Title | Published |
20100319976 | MOTOR CONTROL DEVICE AND VEHICLE STEERING SYSTEM - A motor control device comprising a control board for controlling driving of an electric motor, the control board including a multilayer circuit board having inner layers and outer layers, a ground pattern disposed around an output shaft of the electric motor formed on one of the inner layers, and a severed portion formed on a part of the ground pattern, so as to sever through the ground pattern in a radial direction of the output shaft. The construction reduces noise from the motor control device. | 12-23-2010 |
20100294586 | ELECTRIC POWER STEERING APPARATUS - When stopping operation of an electric power steering apparatus, a motor relay is kept in an on-state even after a power supply relay is in an off-state. A drive control portion sets a target value of a d-axis current to a value other than zero and sets a target value of a q-axis current to zero, and performs a processing same as that at the time of rotating a motor. MOS-FETs contained in a motor driving circuit are controlled such that each of driving currents of the two phases or more is not zero and the brushless motor does not rotate even supplied with these driving currents. Electric charge accumulated in a capacitor is discharged via the MOS-FETs each in an on-state, a motor relay and the windings of the brushless motor. The electric charge accumulated in the capacitor may be discharged via the excitation coil of the motor relay. | 11-25-2010 |