Patents by Inventor Sanshiro Obara

Sanshiro Obara 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).

  • Publication number: 20070084652
    Abstract: A hybrid electric vehicle employs a permanent magnet type dynamo-electric machine having a stator with a stator iron core around which a stator coil is wound, and a rotor arranged in the stator at a rotational gap and having a plurality of permanent magnets arranged and fixed within a rotor iron core in a peripheral direction. A ratio exists between a maximum torque output by the dynamo-electric machine when the dynamo-electric machine normally rotates and a torque output by the dynamo-electric machine when reverse rotating establishes in a relation 1:1.05-1.2, whereby torque at the reverse rotation becomes greater.
    Type: Application
    Filed: December 14, 2006
    Publication date: April 19, 2007
    Applicant: HITACHI, LTD.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Publication number: 20060272870
    Abstract: The invention provides a hybrid electric vehicle employing a permanent magnet type dynamo-electric machine structured such that a torque at a time of reverse rotation is greater than a maximum torque output by a dynamo-electric machine when the dynamo-electric machine normally rotates. Further, the present invention provides a hybrid electric vehicle in which a dynamo-electric machine and an engine are connected to a drive shaft in series and no gear for switching between forward and backward movements is provided, wherein there is employed a permanent magnet type dynamo-electric machine structured such that a torque output by the dynamo-electric machine when the hybrid electric vehicle moves backward (the dynamo-electric machine reverse rotates) is greater than a maximum torque output by the dynamo-electric machine when the hybrid electric vehicle moves forward (the dynamo-electric machine normally rotates).
    Type: Application
    Filed: August 15, 2006
    Publication date: December 7, 2006
    Applicant: HITACHI, LTD.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Patent number: 6963154
    Abstract: A permanent magnet type electric rotating machine comprises a stator having a salient-pole concentrated winding, and a rotor disposed with a rotational gap, and having a plurality of permanent magnets arranged and fixed in a circumferential direction inside, and an auxiliary salient pole provided between the permanent magnets. A ratio of the number of poles for the rotor and the number of slots for the stator is 2:3 and, when a slot pitch of the stator is ?s (electrical angle), an angle ? (electrical angle) made by a circumferential width of the permanent magnet in the surface of the stator side with an axis of the rotor is set at ??n×?s/2+8×m (n=1 or 2, and m=1, 2 or 3). Thus, pulsation torque, cogging torque or the waveform distortion of a no-load induced voltage is selectively reduced as occasion demands.
    Type: Grant
    Filed: June 12, 2002
    Date of Patent: November 8, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Patent number: 6935012
    Abstract: Each of a plurality of unit windings 41 is formed by being divided into a first winding section 42 having opened end portions and a second winding section 43, and the first winding section 42 is shaped in such a manner that a step in radial direction of a stator core 2 is formed between opposing side sections 46 and 47 and the opened end sections are bent in the crossing over direction of the winding so that open ends 443 and 444 of the opened end sections 44 oppose each other in the radial direction of the stator core 2, then the open ends 443 and 444 are connected by winding conductor pieces 431 and 432 of the second winding section to complete the unit winding 41, thereby, end sections of a stator winding are shortened and a small size dynamo electric machine is realized.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: August 30, 2005
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Takashi Yasuhara, Toshiaki Ueda, Yasuhiko Kimura, Sanshiro Obara, Suetaro Shibukawa
  • Publication number: 20050012423
    Abstract: Each of a plurality of unit windings 41 is formed by being divided into a first winding section 42 having opened end portions and a second winding section 43, and the first winding section 42 is shaped in such a manner that a step in radial direction of a stator core 2 is formed between opposing side sections 46 and 47 and the opened end sections are bent in the crossing over direction of the winding so that open ends 443 and 444 of the opened end sections 44 oppose each other in the radial direction of the stator core 2, then the open ends 443 and 444 are connected by winding conductor pieces 431 and 432 of the second winding section to complete the unit winding 41, thereby, end sections of a stator winding are shortened and a small size dynamo electric machine is realized.
    Type: Application
    Filed: August 10, 2004
    Publication date: January 20, 2005
    Inventors: Takashi Yasuhara, Toshiaki Ueda, Yasuhiko Kimura, Sanshiro Obara, Suetaro Shibukawa
  • Patent number: 6791227
    Abstract: Each of a plurality of unit windings 41 is formed by being divided into a first winding section 42 having opened end portions and a second winding section 43, and the first winding section 42 is shaped in such a manner that a step in radial direction of a stator core 2 is formed between opposing side sections 46 and 47 and the opened end sections are bent in the crossing over direction of the winding so that open ends 443 and 444 of the opened end sections 44 oppose each other in the radial direction of the stator core 2, then the open ends 443 and 444 are connected by winding conductor pieces 431 and 432 of the second winding section to complete the unit winding 41, thereby, end sections of a stator winding are shortened and a small size dynamo electric machine is realized.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: September 14, 2004
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Takashi Yasuhara, Toshiaki Ueda, Yasuhiko Kimura, Sanshiro Obara, Suetaro Shibukawa
  • Publication number: 20040112655
    Abstract: The invention provides a hybrid electric vehicle employing a permanent magnet type dynamo-electric machine structured such that a torque at a time of reverse rotation is greater than a maximum torque output by a dynamo-electric machine when the dynamo-electric machine normally rotates. Further, the present invention provides a hybrid electric vehicle in which a dynamo-electric machine and an engine are connected to a drive shaft in series and no gear for switching between forward and backward movements is provided, wherein there is employed a permanent magnet type dynamo-electric machine structured such that a torque output by the dynamo-electric machine when the hybrid electric vehicle moves backward (the dynamo-electric machine reverse rotates) is greater than a maximum torque output by the dynamo-electric machine when the hybrid electric vehicle moves forward (the dynamo-electric machine normally rotates).
    Type: Application
    Filed: November 21, 2003
    Publication date: June 17, 2004
    Applicant: Hitachi Ltd.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Patent number: 6555988
    Abstract: In an arrangement having an electric power inverter 2 which applies a voltage to an AC motor 1 and a control unit 4 which calculates a voltage command value applied in PWM signals, detection use voltages Vup, Vvp and Vwp are applied in synchronism with PWM signal generation use carrier waves in the control unit 4 as well as motor currents iv and iv are detected in response to current detection pulses Pd in synchronism therewith. In a magnetic pole position detection unit 12, counter electromotive forces of the synchronous motor 1 are estimated from a relationship between the detection use voltages Vup, Vvp and Vwp and current difference vectors of the motor current to determine a magnetic pole position &thgr; through calculation. The determined magnetic pole position &thgr; is inputted to coordinate conversion units 8 and 11 and a motor speed detection unit 13.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: April 29, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Ryoso Masaki, Satoru Kaneko, Sanshiro Obara, Mitsuyuki Hombu, Yoshimi Sakurai
  • Publication number: 20020153795
    Abstract: A permanent magnet type electric rotating machine comprises a stator having a salient-pole concentrated winding, and a rotor disposed with a rotational gap, and having a plurality of permanent magnets arranged and fixed in a circumferential direction inside, and an auxiliary salient pole provided between the permanent magnets. A ratio of the number of poles for the rotor and the number of slots for the stator is 2:3 and, when a slot pitch of the stator is &tgr;s (electrical angle), an angle &thgr; (electrical angle) made by a circumferential width of the permanent magnet in the surface of the stator side with an axis of the rotor is set at &thgr;≈n×&tgr;s/2+8×m (n=1 or 2, and m=1, 2 or 3). Thus, pulsation torque, cogging torque or the waveform distortion of a no-load induced voltage is selectively reduced as occasion demands.
    Type: Application
    Filed: June 12, 2002
    Publication date: October 24, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Publication number: 20020117928
    Abstract: Each of a plurality of unit windings 41 is formed by being divided into a first winding section 42 having opened end portions and a second winding section 43, and the first winding section 42 is shaped in such a manner that a step in radial direction of a stator core 2 is formed between opposing side sections 46 and 47 and the opened end sections are bent in the crossing over direction of the winding so that open ends 443 and 444 of the opened end sections 44 oppose each other in the radial direction of the stator core 2, then the open ends 443 and 444 are connected by winding conductor pieces 431 and 432 of the second winding section to complete the unit winding 41, thereby, end sections of a stator winding are shortened and a small size dynamo electric machine is realized.
    Type: Application
    Filed: August 31, 2001
    Publication date: August 29, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Yasuhara, Toshiaki Ueda, Yasuhiko Kimura, Sanshiro Obara, Suetaro Shibukawa
  • Publication number: 20020112904
    Abstract: A hybrid electric vehicle has a permanent magnet type dynamo-electric machine whose torque during reverse rotation is greater than its maximum torque in forward rotation. The dynamo-electric machine is connected in series with an engine and a drive shaft, and no gear is provided for switching between forward and backward movements. The dynamo-electric machine has a stator with a stator iron core around which a stator coil is wound, and a rotor arranged in the stator at a rotational gap and having a plurality of permanent magnets arranged and fixed within a rotor iron core in a peripheral direction. The ratio between a maximum torque output by the dynamo-electric machine when the dynamo-electric machine normally rotates and a torque output by the dynamo-electric machine when reverse rotating is in the range of 1:1.05-1.2, wherein the torque in reverse rotation is greater.
    Type: Application
    Filed: February 8, 2002
    Publication date: August 22, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Patent number: 6429565
    Abstract: A permanent magnet type electric rotating machine comprises a stator having a salient-pole concentrated winding, and a rotor disposed with a rotational gap, and having a plurality of permanent magnets arranged and fixed in a circumferential direction inside, and an auxiliary salient pole provided between the permanent magnets. A ratio of the number of poles for the rotor and the number of slots for the stator is 2:3 and, when a slot pitch of the stator is &tgr;s (electrical angle), an angle &thgr; (electrical angle) made by a circumferential width of the permanent magnet in the surface of the stator side with an axis of the rotor is set at &thgr;≈n×&tgr;s/2+8×m (n=1 or 2, and m=1, 2 or 3). Thus, pulsation torque, cogging torque or the waveform distortion of a no-load induced voltage is selectively reduced as occasion demands.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: August 6, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Osamu Koizumi, Sanshiro Obara
  • Publication number: 20020091470
    Abstract: Control equipment for an electric car and a control method thereof can be realized with control equipment for an electric car mounted with a plurality of rotating machines equipped with a plurality of microcomputers for individually controlling each rotating machine with a simple configuration in such a manner as to enable diagnosis of abnormalities of the control equipment to a high degree of precision. The plurality of microcomputers for individually controlling each rotating machine at the control equipment of the electric car comprise a control data calculator for generating control data for controlling respective target rotating machines and a fault diagnosis module for transmitting and receiving the control data to and from another microcomputer as control data for diagnosis use via a communication device, comparing the control data and the control data for diagnosis use, and diagnosing the presence or absence of a fault. An electric car comprising a plurality of microcomputers, e.g.
    Type: Application
    Filed: January 17, 2002
    Publication date: July 11, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Kazuyoshi Sasazawa, Eiichi Ohtsu, Sanshiro Obara, Nobunori Matsudaira
  • Patent number: 6373219
    Abstract: An object of the present invention is to provide a motor control system comprising an R/D converter which is capable of outputting a good phase signal without being affected by the switching noise due to a PWM signal of an inverter and a motor control method. A motor control system comprising a motor 3 having a resolver 8 as a rotary sensor; an inverter 10 for driving the motor; and a control unit 11 for controlling the inverter, the control unit executing phase calculation processing based on a phase signal which is an output of the resolver converted by an R/D converter 15, calculating a voltage reference based on a current reference and a current value of the motor detected by a current sensor 12, generating a PWM signal for controlling the inverter based on the voltage reference, wherein a PWM synchronism signal 212 in synchronism with the PWM signal is generated in the control unit, and the R/D converter 15 is driven using the PWM synchronism signal.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: April 16, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Sanshiro Obara, Hiroshi Katayama, Yasuo Morooka
  • Patent number: 6320349
    Abstract: A power corresponding to an A/C voltage command id1* is applied in the d-axis direction of rotational coordinates of a stopped synchronous motor via a current control unit, a three-phase converting unit, and a power converter. Further, by using “an amplitude value of a current iq′ in the q-axis direction of the rotational coordinates generated in response to the A/C voltage command id1*” which is fed back and detected via a current detector and a dq converting unit, a field pole position estimation value &thgr;{circumflex over ( )} is converged. The field pole position is estimated by using the converged field pole position estimation value &thgr;{circumflex over ( )} as a true value of the field pole position &thgr; of the synchronous motor.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: November 20, 2001
    Inventors: Satoru Kaneko, Ryoso Masaki, Yuusuke Takamoto, Taizou Miyazaki, Sanshiro Obara
  • Patent number: 6255798
    Abstract: A more compact and light-weight drive unit is required for an electric vehicle in order to improve its mileage per charge, acceleration performance and overall efficiency. A control apparatus which generates drive signals to drive power devices in the power converter includes: a current reference generator calculates from a torque reference value a d-axis exciting current reference value on the basis of which the ac motor generates a magnetic flux, and a q-axis torque current reference value, the d-axis and the q-axis being orthogonal to each other; a current control circuit generates ac voltage reference values Vu*, Vv* and Vw* from the d-axis exciting current reference value and the q-axis torque current reference value; and a drive signal generator generates drive signals to drive power devices from the ac voltage reference values. Both the current reference generator and the current control circuit are processed digitally by the same arithmetic unit.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: July 3, 2001
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Sanshiro Obara, Ryoso Masaki, Yuusuke Takamoto, Eiichi Ohtsu, Hiroyuki Yamada
  • Publication number: 20010002784
    Abstract: In an arrangement having an electric power inverter 2 which applies a voltage to an AC motor 1 and a control unit 4 which calculates a voltage command value applied in PWM signals, detection use voltages Vup, Vvp and Vwp are applied in synchronism with PWM signal generation use carrier waves in the control unit 4 as well as motor currents iv and iv are detected in response to current detection pulses Pd in synchronism therewith. In a magnetic pole position detection unit 12, counter electromotive forces of the synchronous motor 1 are estimated from a relationship between the detection use voltages Vup, Vvp and Vwp and current difference vectors of the motor current to determine a magnetic pole position &thgr; through calculation. The determined magnetic pole position &thgr; is inputted to coordinate conversion units 8 and 11 and a motor speed detection unit 13.
    Type: Application
    Filed: December 1, 2000
    Publication date: June 7, 2001
    Applicant: Hitachi, Ltd.
    Inventors: Ryoso Masaki, Satoru Kaneko, Sanshiro Obara, Mitsuyuki Hombu, Yoshimi Sakurai
  • Patent number: 6236172
    Abstract: A method and apparatus for driving an electric vehicle having a synchronous traction motor. A peak value of induced electromotive force of the synchronous motor at a maximum allowable rotating speed is set to a value which is lower than an allowable voltage of the smoothing capacitor of the inverter and lower than a maximum allowable voltage of the power switching elements composing the inverter. The synchronous motor is thus constructed so that a peak value V0max of the maximum induced electromotive force at the maximum allowable rotating speed N2 of the synchronous motor satisfies a relation of V0max≦VCmax where VCmax is an allowable voltage of the smoothing capacitor.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: May 22, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Sanshiro Obara, Hiroshi Katada, Suetaro Shibukawa, Nobunori Matsudaira, Shotaro Naito
  • Patent number: 6198256
    Abstract: A control apparatus for a synchronous generator system has: a voltage instruction generator for generating voltage instructions (Vu*, Vv*, Vw*) based on an output power reference (P*) of the synchronous generator, currents (Iu, Iv) flowing through the synchronous generator and position information (&thgr;0, &ohgr;r) of magnetic poles of the synchronous generator; a zero crossing point detector for detecting a point that the voltage (Vu) of the synchronous generator passes through zero volt.; and a magnetic pole position calculator for calculating the information (&thgr;0, &ohgr;r) on the position of magnetic poles of the synchronous generator on the basis of the voltage instruction (Vu*) and the power reference (P*) when the synchronous generator is under the generation mode, and on the basis of an output signal of the zero crossing point detector when the synchronous generator is under the stand-by mode.
    Type: Grant
    Filed: September 9, 1999
    Date of Patent: March 6, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Taizou Miyazaki, Ryoso Masaki, Satoru Kaneko, Kazuyoshi Sasazawa, Sanshiro Obara, Nobunori Matsudaira
  • Patent number: 6154002
    Abstract: A control apparatus of an electric motor vehicle includes a device for operating an initial magnetic pole location based on three phase magnetic pole location signal pulses of a permanent magnet electric motor upon starting the electric motor vehicle, a device for operating a magnetic pole phase of the permanent magnet electric motor on the basis of the initial magnetic pole location, a rotation pulse of the permanent magnet electric motor, and a correction value which are operated with the rise and fall of the three phase magnetic pole location signal pulse after the starting, a device for determining a current to be supplied into the permanent magnet electric motor based on the magnetic pole phase and a torque reference value, and a device for correcting the magnetic pole phase when a predetermined one of the three phase magnetic pole location signal pulses rises or falls.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: November 28, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Katsuyuki Izumisawa, Sanshiro Obara, Toshisada Mitsui