Denso Corporation

Nippon Soken, Inc.

Masaya Ootake

Kiyoshi Nagata

Yuuji Hidaka

Tetsuo Hayakawa

Nobumasa Ueda

Sadahiro Akama

Masahiro Kuroda

Yuji Hayashi

Hirokazu Toyoda

Manabu Nomura

Hiroyasu Baba

Shuji Agatsuma

Hiromi Sakai

Daiji Furuhashi

Naoki Yamamoto

Yuichirou Oota

A fuel pump includes a pump cover at one end portion of the housing, a cover end at the other end portion of the housing, a bearing supported by the cover end and rotatably supporting an end portion of the shaft on the cover end-side. The cover end includes a base part that covers the other end portion, a discharge part that is connected to the base part, a bearing accommodating part which is formed such that a cross-section of the bearing accommodating part perpendicular to a rotation axis of the shaft has an annular shape and which includes an accommodating space accommodating the bearing, and a connection part that connects together the base part and the bearing accommodating part. A length of the connection part is shorter than a length of the base part and a length of the bearing accommodating part, in a direction of the rotation axis.

Fuel pump

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.

A cover end of a fuel pump is formed by resin molding and has a tubular portion, which holds a bearing that is placed along a central axis of the tubular portion and rotatably supports one end portion of a shaft of a motor arrangement. Furthermore, three terminals, which supply three-phase electric power received from an outside to windings on a phase-by-phase basis, are insert molded in the cover end. In the cover end, a first transverse passage, which is formed between the first terminal and the second terminal in a circumferential direction, and a second transverse passage, which is formed between the second terminal and the third terminal in the circumferential direction, are configured into a form of V-shape, which diverges in a radially outer direction, in a view taken in an axial direction.

Liquid pump

Partitioned chambers of an electric connector, which receive connection terminals electrically connected to windings of a stator, are communicated with an outside of the electric connector through primary communication holes. The primary communication holes are formed to direct at least one of perpendicular directions, each of which is perpendicular to a corresponding one of opening planes of outside openings of the primary communication holes, toward a downside when a central axis of a fuel pump is tilted relative to a vertical direction. In this way, a foreign object, which is accumulated in any of the portioned chambers, can be outputted to the outside through the primary communication hole even when the fuel pump is tilted in any direction.

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 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

Rotational pump

An electric motor has multiple core portions, multiple bobbins covering the respective core portions, and multiple coil windings wound on the respective core portions and bobbins. Each of the bobbins has a first and a second circumferential forward ends, at which a first and a second holding portions are formed. The first holding portion holds a winding-start portion and the second holding portion holds a winding-end portion. The winding-start portion is prevented from being brought into contact with the winding-end portion and main winding portion of the coil winding between the winding-start portion and the winding-end portion.

Electric motor and fuel pump using the same having circumferential holding grooves for beginning and end portions of coil windings

A motor part of a fuel pump is a brushless motor having a stator and a rotor. The stator has a core, a coil set and an insulator, which holds the core and the coil set in an insulated manner. The coil set has a plurality of coils wound about a tooth part and a plurality of crossing wires connecting the coils. The insulator is formed by stacking central ring parts of a plurality of stator units in an axial direction. At least one of crossing wire holder parts is formed of a combination of guide projections, which are formed on the different central ring parts. The length of the brushless motor in the axial direction can thus be shortened.

Brushless motor with crossing wire holder

A control system controls a multiphase rotating machine by a 120&#xb0; energization process and a PWM process. In the 120&#xb0; energization process, respective ones of switching elements of a high side arm and switching elements of a low side arm of a power conversion circuit are turned on. In the PWM process, the switching elements of the power conversion circuit turn on/off so that two phases that are connected to the switching elements that are in the on-state are alternately rendered conductive to the high potential side input terminal and the low potential side input terminal of the power conversion circuit.

Control system for multiphase electric rotating machine

An electric fuel pump is disclosed which includes a pump portion, a motor portion, a housing, and a fuel passage. The pump portion pressurizes fuel. The motor portion drives the pump portion. The motor portion includes a rotor with a rotating shaft and a stator that surrounds an outer periphery of the rotor. The housing surrounds, at least, an outer periphery of the stator of the motor portion. The fuel passage, through which the fuel pressurized by the pump portion passes the motor portion, is made up of a clearance between the outer periphery of the stator of the motor portion and an inner periphery of the housing. The clearance extends, at least, in the axial direction of the rotating shaft of the rotor of the motor portion.

Growing community of inventors

Kariya, Japan

Masaya Ootake