Denso Corporation

Kazuhiro Yoshida

Jun Yamada

Seiji Nakayama

Masaaki Shinojima

Haruki Matsuzaki

Hiromitsu Nagata

Yuusaku Kawaguchi

Takuya Tamaru

A motor control device is provided with a control circuit and a driving circuit. The control circuit switches over a current supply phase of the motor in a predetermined angular rotation of the rotor a first switching number of times in an acceleration range. The control circuit switches over the current supply phase of the motor in the predetermined angular rotation of the rotor a second switching number of times in a stationary rotation range in a specific condition that the rotation speed of the rotor is between a predetermined first threshold value and a predetermined second threshold value. The control circuit sets the second switching number to be smaller than the first switching number. In the acceleration range, the switching number is relatively large and hence a sufficient driving torque is applied to the rotor. In the stationary rotation range, the switching number is relatively small and hence the control circuitneeds to operate less, a current supply period for the motor is shortened and heat generation is suppressed.

Motor control device

A shift position switching controller determines whether the responsiveness for switching the shift position to an other-than-N position will be affected by a reduction of an N position check time and keeps the N position check time unchanged from a normal value if a current shift position is a D position or if a vehicle speed is equal to or greater than a preset value. Alternatively, the shift position switching controller determines whether the responsiveness of the controller will be affected by reducing the N position check time, and sets the N position check time to a shorter-than-normal value if the current shift position is a D position and the vehicle speed is equal to or greater than the preset value.

Shift position switching controller

When electric power supply is started, an initial driving operation is performed to switch over a power supply phase of a motor in open-loop control. Initial learning processing is performed to learn a phase deviation correction value for the power supply phase relative to a count value of a pulse signal of an encoder. As a restraint caused by a shape of a detent mechanism, the motor need be rotationally driven so that a detent lever does not move in a negative direction beyond a bottom position of a P-range in the initial driving operation. In a case of performing the initial learning processing in the P-range in consideration of this restraint, the initial learning processing is performed by setting a rotation direction of the motor.

Range switchover apparatus

A shift-by-wire system, including a controller that includes a motor driver, and a microcomputer connected to the motor driver to control a motor that drives a control object. The control object has a park lock mechanism having a lock state and an unlock state. The lock state and the unlock state are switched according to an operation position of the control object. The controller is configured to estimate a tilt of a vehicle, detect whether the lock mechanism is in the lock state or in the unlock state, and adjust a target rotation speed of the motor according to the estimated tilt when the operation position of the control object is changed for switching the lock state to the unlock state.

Controller and shift-by-wire system using the controller

A control apparatus controlling a motor for driving an object to switch a shift range of a transmission includes: switching devices for energization to windings of the motor; a controller for the switching devices; a current detecting circuit for a current in the windings and the switching device; a current limit circuit keeping an average of the current within a predetermined range; a standard position learning device of the motor at a learning range such that the current limit circuit limits the current, and the motor rotates until the object stops at a limit position of a movable range; a shift range determination device; and an error determination device determining that the current detecting circuit or the current limit circuit malfunctions when the object does not reach the limit position, the shift range is in a non-learning range, and the standard position learning device starts to learn the standard position.

Control apparatus and shift-by-wire system having the same

A SBW-ECU switches over a shift range to a selected range by rotationally driving a motor to a target position corresponding to the selected range. When a direction of rotation of the motor is the same as a direction toward the target position and a difference between the target position and a present position is larger than a threshold value in a case that the selected range is changed during rotational driving of the motor, the target position is updated to a post-change target position. When the direction of rotation of the motor is opposite to the direction toward the target position or the difference between the target position and the present position is smaller than the threshold value in the case that the selected range is changed during rotational driving of the motor, the target position is updated to the post-change target position after completing the switchover to the pre-change selected range.

Range switchover control system

A motor control apparatus includes a by-wire control circuit for sequentially switching an energized phase of a motor. The by-wire control circuit pre-stores a first table defining an energized phase address corresponding to each address and a second table defining an energized phase corresponding to each energized phase address. When receiving a drive permission code from a second control circuit, the by-wire control circuit switches the energized phase in a correct order of driving the motor, by calculating an address for access to the first table based on the drive permission code, calculating an energized phase address corresponding to the address by referring to the first table, and determining the energized phase corresponding to the energized phase address by referring to the second table.

Motor control apparatus

A control apparatus controlling a motor for driving an object includes: a relay allowing and interrupting electric power supply to the motor; switching devices in multiple phases for allowing and interrupting energization to windings; a controller for the relay and the switching devices; a current detecting circuit for a current flowing through a merging point of the windings and the switching devices; a current limit circuit for keeping an average of the current within a predetermined range; a standard position learning device for learning a standard position of the motor; a voltage detecting circuit for detecting a voltage applied to each switching device; and an error detecting device for detecting an error in the current detecting circuit based on the voltage and the current when the relay turns on, and all switching devices turn off.

A control apparatus controlling a motor for driving an object includes: switching devices in multiple phases, each of which allows and interrupts energization to a corresponding winding of the motor; a controller for the switching devices; a current detecting circuit for a current flowing through each winding and each switching device; a current limit circuit limiting the current to match to a current limiting value; a standard position learning device learning a standard position of the motor such that the current limit circuit limits the current, and the motor rotates until the object stops at a limit position of a movable range; a rotation angle change amount detecting device detecting a change amount of a rotation angle of the object; and an error determination device determining that the current detecting circuit malfunctions when the change amount is out of a predetermined range, and the object changes between first and second states.

A range switching device provides a feedback control for rotating a motor toward a target rotation position. When a target shift range is switched, the range switching device rotates the motor toward a target rotation position by sequentially switching power supply phases of the motor based on an encoder count value. When the motor rotates within a predetermined stop range, the feedback control ends and a power supply to the motor is stopped. However, if the motor has not rotated to the target rotation position after a predetermined time has elapsed from the stopping of the power supply to the motor, an open drive is performed, in which the power supply phase of the motor is sequentially switched by open-loop control and the motor is rotated in small and/or minute steps toward the target rotation position. In such manner, position accuracy of the shift range switching is improved.

Range switching device

A range switching device may switch a shift range despite resetting and restarting of a controller. When the controller is reset and restarted during a switching operation of the shift range and the shift range before or after being switched is a P range, the controller controls a motor to rotate the motor until a range switching mechanism abuts against a first limit position of a movable range of the range switching mechanism and learns a rotation position of the motor as a reference position of the motor. When the shift ranges before and after being switched are the ranges other that the P range, the controller controls the motor to rotate until the range switching mechanism abuts against a second limit position of the movable range and learns the rotation position of the motor as the reference position.

An actuator control apparatus including a by-wire control circuit, a monitor circuit, a drive determination section, and a prohibition section is provided. The by-wire control circuit electrically controls an actuator acting as a drive source of an on-board apparatus. The monitor circuit monitors whether or not the by-wire control circuit is normally operating. The monitor circuit is provided separately from the by-wire control circuit. The drive determination section determines prohibition and permission of driving the actuator. The prohibition section prohibits the actuator from being driven when the permission of driving the actuator is not determined by the drive determination section. The prohibition section also prohibits the actuator from being driven when the monitor circuit determines that the by-wire control circuit is not normally operating.

Growing community of inventors

Tokoname, Japan

Kazuhiro Yoshida