Patents by Inventor Hirofumi Atarashi

Hirofumi Atarashi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7804261
    Abstract: A motor control method that includes the steps of: rotationally driving a motor that is provided with a rotor having permanent magnet pieces, and a stator; and short circuiting a plurality of phases of the motor when the rotational frequency of the motor is equal to or greater than a predetermined rotational frequency.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: September 28, 2010
    Assignee: Honda Motor Co., Ltd
    Inventors: Hirofumi Atarashi, Hiroyuki Isegawa
  • Publication number: 20100231079
    Abstract: The present axial gap motor is provided with: a rotor that is rotatable around a rotation axis; and a pair of stators that are opposed to each other with the rotor interposed therebetween from both sides in a rotation axis direction which is parallel with the rotation axis of the rotor. The rotor includes: a plurality of main magnets arranged in a circumferential direction so that a flux direction is parallel with the rotation axis direction; a sub permanent magnet which is disposed in the vicinity of a circumferential end portion of the main magnet and is magnetized in a direction perpendicular to the rotation axis direction and a radial direction; and a magnetic member which is provided on a surface of at least one of the one side and the other side in the rotation axis direction of the main magnet. A length of the magnetic member in the rotation axis direction is larger than a length of the sub permanent magnet in the rotation axis direction.
    Type: Application
    Filed: July 9, 2008
    Publication date: September 16, 2010
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Shoei Abe, Hirofumi Atarashi, Keiichi Yamamoto
  • Publication number: 20100219710
    Abstract: The axial gap motor includes the rotor having: a rotor frame including a plurality of ribs extending in a radial direction, an inner circumferential side annular shaft, and an outer circumferential side annular rim, which are integrally coupled to each other through the ribs; the shaft has shaft side rib mounting holes through which the ribs are mounted, the rim has rim side rib mounting holes through which the ribs are mounted, the ribs have radial inner ends mounted and fixed into the shaft side rib mounting holes and radial outer ends mounted and fixed into the rim side rib mounting holes, and in the rotor frame, the main magnets and the sub magnets are alternately disposed in the circumferential direction, between the shaft and the rim.
    Type: Application
    Filed: October 2, 2008
    Publication date: September 2, 2010
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Tamotsu Kawamura, Keiichi Yamamoto, Hirofumi Atarashi, Shoei Abe, Shigeru Tajima
  • Publication number: 20100187933
    Abstract: There is provided an axial gap motor including a rotor rotatable around a rotation axis; and a first stator and a second stator arranged to face each other with the rotor therebetween from both sides of the rotor in the rotation axis direction of the rotor, wherein the rotor includes a plurality of main permanent magnets having magnetizing directions in the rotation axis direction of the rotor and arranged in a peripheral direction of the rotor; a partition member arranged between the main permanent magnets which are adjacent to each other in the peripheral direction of the rotor, the partition member including a nonmagnetic material; and auxiliary permanent magnets having a magnetizing direction that is orthogonal both to the rotation axis direction of the rotor and a radial direction of the rotor, and arranged on both sides of the partition member in the rotation axis direction of the rotor.
    Type: Application
    Filed: June 11, 2008
    Publication date: July 29, 2010
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Keiichi Yamamoto, Hirofumi Atarashi, Shoei Abe
  • Patent number: 7755314
    Abstract: An electric-motor-equipped vehicle of the present invention includes an electric motor which receives a power supply from a storage apparatus and drives the vehicle, or assists a driving of the vehicle by an internal combustion engine. The electric motor includes: an inner circumference side rotor and an outer circumference side rotor which are each provided with magnet pieces, and rotation axes of which are coaxially arranged; a stator which is arranged on an outer circumferential side or an inner circumferential side of the inner circumference side rotor and the outer circumference side rotor; and a phase modification device capable of modifying a relative phase between the inner circumference side rotor and the outer circumference side rotor.
    Type: Grant
    Filed: February 19, 2007
    Date of Patent: July 13, 2010
    Assignee: Honda Motor Co., Ltd.
    Inventors: Hirofumi Atarashi, Hiroyuki Isegawa, Hiromitsu Sato, Masaaki Kaizuka, Shoei Abe
  • Patent number: 7741792
    Abstract: A motor control device includes: a motor that has a plurality of rotors which respectively have a magnetic piece, which drives or supplementarily drives a vehicle; a phase changing mechanism that changes relative phases of the plurality of rotors, and sets these to a predetermined induced voltage constant; and a speed control device that controls a phase changing speed of the phase changing mechanism.
    Type: Grant
    Filed: August 14, 2007
    Date of Patent: June 22, 2010
    Assignee: Honda Motor Co., Ltd.
    Inventors: Naoki Fujishiro, Hirofumi Atarashi, Hiroyuki Isegawa
  • Patent number: 7737594
    Abstract: An axial gap type motor according to the present invention includes: a rotor; and a pair of stators which are arranged to face each other and hold the rotor from both sides thereof along a rotation axis. The rotor includes: electromagnets which are provided on the rotor as main magnets, and arranged along a circumferential direction so that directions of magnetic fluxes thereof are parallel to the rotation axis; and sub permanent magnets which are provided on the rotor, arranged in the vicinities of circumferential end portions of the main magnets, and are magnetized orthogonal to the rotation axis and a radial direction.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: June 15, 2010
    Assignee: Honda Motor Co., Ltd.
    Inventors: Shoei Abe, Hirofumi Atarashi, Keiichi Yamamoto, Shigeru Tajima, Makoto Kawakami, Takeo Fukuda
  • Publication number: 20100141075
    Abstract: An axial gap motor, including: a rotor having permanent magnet pieces; and a pair of stators that are oppositely arranged so as to sandwich the rotor in a rotation axis direction thereof, wherein: the rotor includes magnetic material pieces that are arranged along a circumferential direction thereof in a manner alternating with the permanent magnet pieces; the permanent magnet pieces have a magnetization direction in parallel with the rotation axis direction, with N poles thereof opposed to the stator on one side in the rotation axis direction, and with S poles thereof opposed to the stator on the other side in the rotation axis direction; and each of the magnetic material pieces includes magnetic material piece penetration portions that penetrate in a direction parallel to the rotation axis direction.
    Type: Application
    Filed: October 29, 2007
    Publication date: June 10, 2010
    Applicant: Honda Motor Co., Ltd
    Inventors: Hirofumi Atarashi, Hiroyuki Isegawa, Shoei Abe, Keiichi Yamamoto, Shigeru Tajima
  • Publication number: 20100117474
    Abstract: An axial gap motor includes: a rotor; and a stator, wherein: the rotor includes a plurality of main permanent magnet parts and a plurality of auxiliary permanent magnet parts, the auxiliary permanent magnet parts being disposed near an end portion of each of the main permanent magnet parts and a magnetizing direction of each of the auxiliary permanent magnet parts corresponding to a direction perpendicular to the direction of the rotational axis; each of the stators includes a plurality of teeth arranged in a circumferential direction and protruding toward the rotor along the rotational axis, and a circumferential distance between a circumferential direction first end and a circumferential direction second end of each of the auxiliary permanent magnet parts on a surface opposite the stator is larger than a slot width of a slot defined between the teeth adjacent in the circumferential direction.
    Type: Application
    Filed: February 25, 2008
    Publication date: May 13, 2010
    Applicant: Honda Motor Co Ltd
    Inventors: Hirofumi Atarashi, Shoei Abe, Keiichi Yamamoto
  • Patent number: 7683520
    Abstract: This electric motor is provided with an inner periphery side rotor, an outer periphery side rotor, and a rotating device that can change a relative phase between these rotors by rotating at least one of them about a rotational axis thereof. The rotating device is provided with a first member integrally and rotatably provided to the outer periphery side rotor, and a second member integrally fixed on an inside of the inner periphery side rotor which together with the first member defines a pressure chamber on the inside of the inner periphery side rotor. The rotating device changes a relative phase between the inner periphery side rotor and the outer periphery side rotor by supplying a hydraulic fluid to the pressure chamber. The rotating device is further provided with a linking passage that leaks the hydraulic fluid supplied to the pressure chamber to an outside of the pressure chamber.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: March 23, 2010
    Assignee: Honda Motor Co., Ltd.
    Inventors: Tamotsu Kawamura, Hirofumi Atarashi, Masaaki Kaizuka, Shoei Abe, Kazuyuki Iwata, Masato Fujioka
  • Patent number: 7679260
    Abstract: An axial gap motor including a rotor and stators, wherein: the rotor is provided with a plurality of primary magnet portions, a plurality of auxiliary magnet portions, and a rotor frame; the rotor frame is provided with a plurality of ribs that extend in the radial direction of the rotor frame, and a shaft portion and a rim portion that are integrally connected with each other via the ribs, and the rotor frame houses the primary magnet portions and the auxiliary magnet portions; the primary magnet portions are provided with primary permanent magnet pieces; the auxiliary magnet portions are provided with auxiliary permanent magnet pieces; and each of cross-sectional areas of the ribs which is perpendicular to the radial direction increases from the rim portion side towards the shaft portion side in the radial direction.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: March 16, 2010
    Assignee: Honda Motor Co., Ltd.
    Inventors: Keiichi Yamamoto, Hirofumi Atarashi, Shoei Abe, Shigeru Tajima
  • Publication number: 20100026216
    Abstract: A controller for an axial gap-type motor (3) comprises a rotor (11) having a permanent magnet and a first stator (12a) and a second stator (12b) opposed to each other with the rotor (11) interposed therebetween in the axial direction of revolution of the rotor (11). The controller further includes an electrification control portion which supplies a torque current (Iq) for generating a magnetic field to revolve the rotor (11) to an armature winding (13a) of the first stator (12a) and supplies a field current (+Id) for reinforcing the magnetic flux by the permanent magnet of the rotor (11) or a field current (?Id) for weakening the magnetic flux to an armature winding (13b) of the second stator (12b). Consequently, the controllable range of the motor is increased and the axial gap-type motor can be operated at higher velocity and higher torque.
    Type: Application
    Filed: February 26, 2008
    Publication date: February 4, 2010
    Applicant: Honda Motor Co., LTD
    Inventor: Hirofumi Atarashi
  • Patent number: 7626298
    Abstract: This electric motor of the present invention is formed by an inner circumferential side rotor, an outer circumferential side rotor, and a planetary gear mechanism that are placed coaxially. The planetary gear mechanism is a single pinion type that includes a first planetary gear train and a second planetary gear train that are each single gear train. A first planetary carrier that supports the first planetary gear train is able to pivot around an axis of rotation, and a second planetary carrier that supports the second planetary gear train is fixed to a stator. The electric motor is further provided with an actuator that pivots the first planetary carrier by a predetermined pivot amount around the axis of rotation.
    Type: Grant
    Filed: November 27, 2006
    Date of Patent: December 1, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventor: Hirofumi Atarashi
  • Patent number: 7622875
    Abstract: A change in torque produced by a motor having two rotors is reduced when the motor operates in a low-velocity and low-torque operational state. The motor has a first rotor and a second rotor, each of which has a permanent magnet, and an output shaft capable of rotating integrally with the first rotor. The second rotor can relatively rotate with respect to the first rotor by a driving force from a phase difference changing driving device, and the phase difference between the rotors (rotor phase difference) can be changed by the relative rotation of the second rotor with respect to the first rotor. When the values of the torque and the rotational velocity of the motor lie within a predetermined region in the proximity of 0, the phase difference changing driving device adjusts the rotor phase difference to a predetermined phase difference for which the strength of a composite field of the permanent magnets is lower than a maximum strength.
    Type: Grant
    Filed: July 13, 2007
    Date of Patent: November 24, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventors: Hirofumi Atarashi, Hiromitsu Sato, Masanari Fukuchi, Masaaki Kaizuka
  • Patent number: 7622883
    Abstract: There is provided a controller for a motor capable of changing the phase difference between two rotors that can prevent demagnetization of permanent magnets or the rotors. The motor has two rotors each having a permanent magnet and phase difference changing driving means for changing the phase difference between the rotors. The controller has a demagnetization determining means for determining whether or not demagnetization of the permanent magnets of the rotors occurs during operation of the motor, and rotor phase difference controlling means for controlling the phase difference changing driving means to change the phase difference between the rotors from a current phase difference to a phase difference that results in a higher strength of a composite field of the permanent magnets if the result of determination by the demagnetization determining means is positive.
    Type: Grant
    Filed: August 7, 2007
    Date of Patent: November 24, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventors: Masaaki Kaizuka, Hirofumi Atarashi, Masanari Fukuchi, Katsuhiko Furukawa
  • Patent number: 7615948
    Abstract: A controller for a motor and a control method for a motor change an operating condition of each motor, considering difference in operating conditions, such as loss and temperature, thus making it possible to reduce a total loss in a plurality of motors. The controller includes a first motor operating condition calculator and a second motor operating condition calculator which calculate the estimated values of losses incurred when a first motor and a second motor are driven, and a DC voltage control unit which carries out, on a motor having a largest estimated value of loss, the processing for changing a supply voltage to change the voltage of DC power supplied to inverters by a DC/DC converter, thereby reducing the difference between a phase voltage, which is the resultant vector of the voltages across terminals of the motor, and a target voltage set on the basis of an output voltage of the DC/DC converter.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: November 10, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventors: Hirofumi Atarashi, Hiroyuki Isegawa, Masaaki Kaizuka, Masanari Fukuchi
  • Patent number: 7605551
    Abstract: A controller for a motor cleans, as necessary, a hydraulic chamber that generates hydraulic oil for changing a phase difference between two rotors so as to restrain sludge from building up in the hydraulic chamber. A motor has a first rotor and a second rotor that can be relatively rotated with respect to the first rotor. The controller includes a phase difference changing driver that changes the phase difference between the two rotors by controlling the pressure in the hydraulic chamber filled with hydraulic oil. The controller further includes a cleaning need determiner that determines the need for cleaning the hydraulic chamber, and a cleaning phase difference controller that controls the phase difference changing driver such that the second rotor is relatively rotated in the forward direction and the reverse direction alternately with respect to the first rotor if a determination result of the cleaning need determiner is affirmative.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: October 20, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventors: Hirofumi Atarashi, Kazuyuki Iwata
  • Publication number: 20090251021
    Abstract: A rotor (11) is provided with: a main permanent magnet mounting layer (21) having a plurality of main permanent magnets (21a) mounted thereon; a first sub permanent magnet mounting layer (22) having a plurality of first sub permanent magnets (22a) mounted thereon; a second sub permanent magnet mounting layer (23) having a plurality of second sub permanent magnets (23a) mounted thereon; and a phase change mechanism capable, by turning at least either one of the first sub permanent magnet mounting layer (22) and the second permanent magnet mounting layer (23), and the main permanent magnet mounting layer (21) about the rotational axis, of changing the relative phase between the first sub permanent magnet mounting layer (22) and the second permanent magnet mounting layer (23), and the main permanent magnet mounting layer (21).
    Type: Application
    Filed: March 23, 2007
    Publication date: October 8, 2009
    Inventors: Hirofumi Atarashi, Keiichi Yamamoto, Shoei Abe, Shigeru Tajima
  • Publication number: 20090243422
    Abstract: The axial gap type motor according to the present invention is provided with: a rotor and a first stator and a second stator, wherein the first and second stators includes an annular back yoke and a plurality of teeth which is provided on the annular back yoke at predetermined intervals in a peripheral direction so as to protrude toward the rotor in the direction of the rotation axis; the peripheral pitch of the plurality of teeth of the first and second stators are equal to each other; and in a case where the first stator and the second stator which sandwich the rotor therebetween in the direction of the rotation axis are seen from one side in the direction of the rotation axis, facing surfaces of the teeth of the first and second stators which face to the rotor are formed so as not to overlap completely each other.
    Type: Application
    Filed: October 2, 2008
    Publication date: October 1, 2009
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Hirofumi Atarashi, Shoei Abe, Keiichi Yamamoto
  • Patent number: 7583048
    Abstract: A controller for a motor carries out field weakening control by using a simple construction to change the phase difference between two rotors, which are disposed around a rotating shaft, without depending on the number of revolutions of a motor. The controller for a motor includes a field weakening current calculator for calculating a field weakening current command value on the basis of the radius of a target voltage circle, a d-axis voltage command value, and a q-axis voltage command value, a rotor phase difference command value determiner for determining a command value of a rotor phase difference on the basis of the field weakening current command value, and a current command value determiner for determining a d-axis current command value and a q-axis current command value on the basis of the rotor phase difference command value and a torque command value.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: September 1, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventors: Hirofumi Atarashi, Hiroyuki Isegawa, Tamotsu Kawamura