Denso Corporation

Yuuji Hidaka

Kiyoshi Nagata

Masaya Ootake

Yuichi Seo

Hiromi Sakai

Tetsuo Hayakawa

Hirokazu Toyoda

Manabu Nomura

Satoshi Ito

Daiji Furuhashi

Shingo Fukuoka

A motor control device includes: a rotation control determination unit configured to determine whether a motor rotation control to rotate the motor fails; a parameter calculation unit configured to calculate a control failure frequency parameter having a correlation with a frequency of failure in the motor rotation control based on a determination result by the rotation control determination unit; an abnormality determination unit configured to determine whether an abnormality has occurred in the motor based on the control failure frequency parameter; and a stop suppression unit configured to suppress stop of rotation of the motor by changing a motor control parameter to perform the motor rotation control when the abnormality determination unit determines that an abnormality has occurred in the motor.

Motor control device

A motor control device configured to control a motor that drives a fuel pump includes a sign detection unit and a vapor suppression unit. The sign detection unit is configured to detect a sign of a vapor lock that is an abnormality in which the fuel pump is unable to discharge a fuel due to a vapor inside the fuel pump. The vapor suppression unit is configured to change a rotation speed of the motor to reduce the vapor inside the fuel pump when the sign detection unit detects the sign of the vapor lock.

A motor control device includes: a rotation control determination unit configured to determine whether a motor rotation control to rotate the motor fails; a parameter calculation unit configured to calculate a control failure frequency parameter having a correlation with a frequency of failure in the motor rotation control based on a determination result by the rotation control determination unit; and an abnormality determination unit configured to determine whether an abnormality has occurred in the motor based on the control failure frequency parameter.

A fuel pump is connected to a suction filter which is provided with a filter connecting portion having a cylindrical hole and a projecting portion protruding radially inward from an inner peripheral wall of the cylindrical hole. The fuel pump suctions the fuel filtered by the suction filter. The fuel pump is provided with a suction port having multiple suction openings at a side of the suction filter so as to suction the fuel therethrough, and a pump connecting portion provided at outer side of the multiple suction openings and connected with the filter connecting portion. The pump connecting portion has an outer peripheral wall of which outer shape corresponds with a shape of the inner peripheral wall, and a dent portion denting inward from the outer peripheral wall, which the projecting portion is engaged with.

Fuel pump and fuel pump module

A fuel pump has a pump function of sucking fuel in a fuel tank and discharging fuel, and a detection function of detecting a capacitance correlated to a concentration of alcohol in fuel in the fuel tank. The fuel pump includes a pump main body that is received in the fuel tank to perform the pump function, a housing electrode that covers the pump main body in the fuel tank, and an outside electrode that is located outside of the housing electrode in the fuel tank. A gap is formed between the outside electrode and the housing electrode to give the capacitance.

Fuel pump, fuel supply device, and fuel supply control system

A rotor used for a motor that rotates an impeller of a fuel pump includes a cylindrical bonded magnet that forms a plurality of magnetic poles, an inner core that is a cylindrical component provided inward of the bonded magnet and that has both axial end surfaces exposed to outside, and a rotating shaft that includes a connecting end, which has a pair of flat surfaces parallel to each other and is fitted to the impeller, and that is provided to pass through the inner core inward thereof. A cross section of the connecting end has a centroid coinciding with a rotational axis.

Rotor

An ECU of a fuel pump executes a feedback control to drive a motor part and sets a rotation speed of an impeller to become a rotation speed corresponding to the target fuel pressure. The ECU detects whether a vapor is generated in a fuel of a pump chamber of the fuel pump, based on a fuel pressure detected by a pressure sensor. When a generation of the vapor is detected, the ECU sets a rotation speed of the impeller to be higher than the rotation speed under a normal control for a predetermined time with a result that the vapor in the pump chamber and a fuel flow channel is discharged into a vapor discharge hole. Thus, the vapor of the pump chamber is discharged from the vapor discharge hole to an outside of the fuel pump.

Fuel pump and control method therefor including control of rotation speed of impeller

An outer wall surface of an output end portion includes a pair of first plane surfaces which are formed at different positions in its circumferential direction. An inner wall surface of a fitting hole includes a pair of second plane surfaces which are formed at different positions in the circumferential direction. A clearance between one of the pair of first plane surfaces and one of the pair of second plane surfaces is made larger from one side toward the other side in an axial direction in a state that a rotary shaft and an impeller are concentric with each other.

Fuel pump

A microcomputer of a drive control device for controlling the driving of a brushless motor has a positioning part and a torque acceleration control unit. The positioning unit controls the power to be supplied to the windings, to thereby position the rotor at a drive start position which is a position of the rotor relative to the stator at which the drive control of the brushless motor can start, before starting the drive control of the brushless motor. The torque acceleration control unit controls the power to be supplied to the windings so that a torque acceleration falls within a predetermined range that the collision stress generated when the outer wall of the end of the shaft collides with the inner wall of the hole of an impeller (rotating member) is equal to or smaller than a predetermined value, when the rotor is positioned.

Drive control device and fuel pump drive system

A permanent magnet of a rotor core of a rotor includes a first recess and a second recess, which are formed in an outer wall to correct a dynamic balance of the rotor. The permanent magnet is a bonded magnet that is formed by molding a mixture material, which is a mixture of resin and magnetic powder. The first recess and the second recess are formed at the time of molding the permanent magnet. Furthermore, the first recess and the second recess are formed at two axial ends, respectively, of the permanent magnet.

Rotor for brushless motor

A rotor of a brushless motor used in a fuel pump includes a permanent magnet having first and second ends that are configured to have a thickness ratio so that a degree of margin of those ends, which is a difference between an allowable stress and a temperature stress due to expansion and contraction of a rotor core caused by a temperature change is equal to or greater than a preset value. As a result, a cracking of the permanent magnet on the both ends that is caused by repeated expansions and contractions of the rotor core is prevented.

Rotor of brushless motor

A drive controller that controls a drive of a motor. The drive controller performs a collision force moderation control during a motor start time, during which a collision force in a collision between a shaft outwall with an impeller hole inwall for a positioning is moderated, by changing a power supply at a stage transition time of transiting from a position detection to a position determination. The maximum value of a first output value during a position detection time is set to be greater than a first threshold that at least causes a rotation number of the motor to yield a detectable induction voltage. A second output value during a position determination time is set to be lower than a second threshold that causes a wear or a breakage of an impeller by the collision force.

Drive controller and motor drive system

A microcomputer operates as a positioning part positions a rotor at a control start position, which is a position of the rotor relative to a stator to be able to start controlling driving of a brushless motor, by supplying a current to a winding set a number of times 'n' (n is an integer equal to two or more) before starting to control driving of the brushless motor. The microcomputer, operating as the positioning part, controls electric power supplied to the winding set so that the rotor rotates in the same direction at each of 'n' times of power supply to the winding set, that is, at each of &#x201c;n&#x2212;1&#x201d; times of switchovers of power supply to the winding set.

Growing community of inventors

Kariya, Japan

Yuuji Hidaka