Patents by Inventor Yasutomo Kawabata

Yasutomo Kawabata 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: 6553650
    Abstract: A circular wire with a circular cross section is wound on a coil reel. When a winding-form motor rotates a winding form, the circular wire is pulled and drawn from the coil reel. Rectangular forming rollers press the circular wire, so that a rectangular wire with a rectangular cross section is formed. The rectangular wire is directly wound on the winding form to be formed into a rectangular-wire coil. Because forming rectangular wire and winding on the winding form are carried out in a sequence of contiguous processes, a separate process for removing torsion set of the rectangular wire is unnecessary. The rectangular-wire coil can be formed from inexpensive circular material wire by a simple and low-cost apparatus. It is also possible and preferable to make dimensions and a shape of the rectangular wire variable by controlling clearance widths between the forming rollers and tension acting on the rectangular wire that has passed through the rollers.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: April 29, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayuki Nakamura, Yasutomo Kawabata, Masahiro Nishioka, Yasuhiko Ishimaru, Tetsuya Miura, Katsuhisa Endo
  • Patent number: 6520879
    Abstract: A power outputting apparatus is provided with an engine, a clutch motor connected to a crank shaft thereof, and an assist motor connected to the crank shaft or a drive shaft by a switch apparatus. At a time of moving a vehicle backward, an operation characteristic of the engine is set to a characteristic on a low torque side in place of a characteristic at a time of moving forward (a characteristic giving priority to an efficiency). In addition, a torque Tm larger than an engine torque Te and in a reverse direction is output from the assist motor. As a result, a high torque is output to the drive shaft while an electric power is regenerated by the clutch motor, whereby the vehicle can be backward moved.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: February 18, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yasutomo Kawabata, Shigeru Matsuhashi, Nobuyoshi Takagi
  • Patent number: 6515446
    Abstract: The technique of the present invention sets a torque voltage to be applied to a motor in response to a required torque and adjusts the duty of an inverter to ensure application of the torque voltage according to the observed voltage of a battery. In a motor controller constructed to attain such control, before a start-up of normal operation of the motor, a fixed duty is set for switching the inverter to apply a voltage to the motor. The value of electric current running in response to the applied voltage is measured. The mapping of the value of electric current to the source voltage in the case of switching the inverter at a fixed duty is stored in advance in the form of a table. The procedure reads the true value of the source voltage from the table and thereby specifies an offset error occurring in a voltage sensor of the battery. The procedure then corrects the observed voltage of the battery and adequately regulates the torque voltage.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: February 4, 2003
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Satoshi Koide, Yasutomo Kawabata, Eiji Yamada
  • Publication number: 20020115516
    Abstract: A power outputting apparatus is provided with an engine, a clutch motor connected to a crank shaft thereof, and an assist motor connected to the crank shaft or a drive shaft by a switch apparatus. At a time of moving a vehicle backward, an operation characteristic of the engine is set to a characteristic on a low torque side in place of a characteristic at a time of moving forward (a characteristic giving priority to an efficiency). In addition, a torque Tm larger than an engine torque Te and in a reverse direction is output from the assist motor. As a result, a high torque is output to the drive shaft while an electric power is regenerated by the clutch motor, whereby the vehicle can be backward moved.
    Type: Application
    Filed: February 22, 2001
    Publication date: August 22, 2002
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yasutomo Kawabata, Shigeru Matsuhashi, Nobuyoshi Takagi
  • Patent number: 6380640
    Abstract: A method of controlling a power output apparatus including an engine, a drive shaft, first and second electric motors and a coupling device is provided. When a hybrid vehicle starts from rest, ECU operates to run the vehicle in EV mode only by means of one of the electric motors. When the operating point of the drive shaft passes a boundary that separates the underdrive region from the overdrive region, and enters the overdrive region, fuel supply to the engine is started so as to start the engine, and the coupling device is controlled so that coupling of the rotary shaft of the second electric motor is switched from the first coupling state in which the rotary shaft is coupled with the drive shaft to the second coupling state in which the rotary shaft is coupled with the output shaft of the engine. After switching, the ECU operates to run the vehicle in HV mode, utilizing the engine and the first and second electric motors.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: April 30, 2002
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Akihiko Kanamori, Yasutomo Kawabata, Jiro Eto
  • Patent number: 6359359
    Abstract: A rotor piece has a plurality of holes 12. Each hole holds therein a plurality of substantially divided permanent magnets 14 that are arranged in a circumferential direction. Therefore, each permanent magnet is small and the flow passage of eddy currents becomes narrow, so that the magnitude of eddy currents becomes small. The total eddy currents in all the permanent magnets is also reduced, so that the eddy current loss can be reduced and the heat generation of the motor can be reduced. Adjacent ones of the substantially divided permanent magnets may be interconnected at portions thereof. One or more of the substantially divided permanent magnets 14 in one or more holes may be ferrite magnets, with other permanent magnets being rare-earth magnets.
    Type: Grant
    Filed: November 15, 1999
    Date of Patent: March 19, 2002
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tetsuya Miura, Masaru Hirako, Shigetaka Nagamatsu, Yasutomo Kawabata, Tetsuya Sugimoto
  • Patent number: 6340847
    Abstract: In a power output apparatus of the present invention, a control unit sets a WOT (wide open throttle) line L2, where the maximum torque of an engine attains, as a boundary between an over drive area and an under drive area in the case where a rotor shaft of an assist motor is set in a state of over drive linkage. The control unit determines a target working point of an outer rotor shaft of a clutch motor, which functions as a drive shaft, based on an externally required output, and selects the WOT line L2 as a performance line of the engine in the case where the target working point of the outer rotor shaft is present in the under drive area. The control unit then sets a switching instruction flag, in order to change the state of linkage of the rotor shaft of the assist motor from the state of over drive linkage to a state of under drive linkage.
    Type: Grant
    Filed: January 18, 2000
    Date of Patent: January 22, 2002
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yasutomo Kawabata, Shigeru Matsuhashi, Nobuyoshi Takagi, Akihiko Kanamori, Eiji Yamada
  • Publication number: 20010007416
    Abstract: The expected power to be output from a synchronous motor is obtained based on a torque command value and revolution speed of the motor. Meanwhile electric power consumption is detected based on voltage and current actually applied to the motor. If a parameter derived from a deviation or a ratio of the two exceeds a predetermined threshold value, it is determined that step-out has occurred. When using the deviation of the expected power from the electric power consumption as the parameter, the threshold value is determined in relation to the torque command value and the revolution speed. When using the ratio of the expected power and the electric power consumption as the parameter, the threshold value is set in relation to the revolution speed. This enables step-out to be accurately determined with an extremely light computational load.
    Type: Application
    Filed: January 4, 2001
    Publication date: July 12, 2001
    Inventors: Satoshi Koide, Yasutomo Kawabata, Eiji Yamada
  • Publication number: 20010005934
    Abstract: A circular wire with a circular cross section is wound on a coil reel. When a winding-form motor rotates a winding form, the circular wire is pulled and drawn from the coil reel. Rectangular forming rollers press the circular wire, so that a rectangular wire with a rectangular cross section is formed. The rectangular wire is directly wound on the winding form to be formed into a rectangular-wire coil. Because forming rectangular wire and winding on the winding form are carried out in a sequence of contiguous processes, a separate process for removing torsion set of the rectangular wire is unnecessary. The rectangular-wire coil can be formed from inexpensive circular material wire by a simple and low-cost apparatus. It is also possible and preferable to make dimensions and a shape of the rectangular wire variable by controlling clearance widths between the forming rollers and tension acting on the rectangular wire that has passed through the rollers.
    Type: Application
    Filed: February 22, 2001
    Publication date: July 5, 2001
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masayuki Nakamura, Yasutomo Kawabata, Masahiro Nishioka, Yasuhiko Ishimaru, Tetsuya Miura, Katsuhisa Endo
  • Patent number: 6216513
    Abstract: A circular wire with a circular cross section is wound on a coil reel. When a winding-form motor rotates a winding form, the circular wire is pulled and drawn from the coil reel. Rectangular forming rollers press the circular wire, so that a rectangular wire with a rectangular cross section is formed. The rectangular wire is directly wound on the winding form to be formed into a rectangular-wire coil. Because forming rectangular wire and winding on the winding form are carried out in a sequence of contiguous processes, a separate process for removing torsion set of the rectangular wire is unnecessary. The rectangular-wire coil can be formed from inexpensive circular material wire by a simple and low-cost apparatus. It is also possible and preferable to make dimensions and a shape of the rectangular wire variable by controlling clearance widths between the forming rollers and tension acting on the rectangular wire that has passed through the rollers.
    Type: Grant
    Filed: January 27, 1999
    Date of Patent: April 17, 2001
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masayuki Nakamura, Yasutomo Kawabata, Masahiro Nishioka, Yasuhiko Ishimaru, Tetsuya Miura, Katsuhisa Endo
  • Patent number: 6188196
    Abstract: An electrical angle detecting apparatus determines an electrical angle &thgr; from voltages Vd, Vq, and currents Id, Iq along a d-axis and a q-axis of a synchronous motor, by using the following expressions: &thgr;=&thgr;(n−1)+k1×&Dgr;Id+k2×&Sgr;(&Dgr;Id) &Dgr;Id=Id(n)−Id(n−1)−t(Vd−R×Id(n−1)+&ohgr;×Lq×Iq(n−1))/Ld; &ohgr;=(k1×&Dgr;Id+k2×&Sgr;(&Dgr;Id))/t where (n−1) indicates a value of each variable at the previous timing; (n) indicates a value at the given timing; R is the resistance of a coil; t is the determination executing period; and k1, k2 are coefficients. This determination makes it easier to set appropriate gains, so that precision improves. Furthermore, the amount of determination reduces, and the processing time shortens.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: February 13, 2001
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Satoshi Koide, Yasutomo Kawabata, Eiji Yamada
  • Patent number: 6166499
    Abstract: A power output apparatus 20 implements a smooth switching between the connection of a rotor-rotating shaft 38 of an assist motor 40 with a crankshaft 56 of an engine 50 and the connection of the rotor-rotating shaft 38 of the assist motor 40 with a drive shaft 22, and enables the power output from the engine 50 to be output to the drive shaft 22 with a high efficiency. The power output from the engine 50 is converted to a desired power by a clutch motor 30 having rotors 31 and 33 respectively linked with the crankshaft 56 and the drive shaft 22 and by the assist motor 40 connected to either the crankshaft 56 or the drive shaft 22 via a first clutch 45 and a second clutch 46, and is output to the drive shaft 22. The connection of the assist motor 40 is switched in the state where both the clutches 45 and 46 are set in ON position, when the revolving speed of the engine 50 is made coincident with the revolving speed of the drive shaft 22.
    Type: Grant
    Filed: February 23, 1998
    Date of Patent: December 26, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Akihiko Kanamori, Yasutomo Kawabata, Norihiko Akao, Hiroaki Urano, Masaru Hirako, Tetsuya Miura
  • Patent number: 6087734
    Abstract: A power output apparatus 20 includes a clutch motor, an assist motor, and a controller. The clutch motor and the assist motor are controlled by the controller to enable the power output from an engine to a crankshaft 56, and expressed as the product of its revolving speed and torque, to be converted to the power expressed as the product of a revolving speed and a torque of a drive shaft and to be output to the drive shaft. The engine can be driven at an arbitrary driving point defined by a revolving speed and a torque, as long as the energy or power output to the crankshaft is identical. A desired driving point that attains the highest possible efficiency with respect to each amount of output energy is determined in advance. In order to allow the engine to be driven at the desired driving point, the controller controls the clutch motor and the assist motor as well as the fuel injection and the throttle valve position.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: July 11, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tomoharu Maeda, Yoshihide Nii, Shoichi Sasaki, Takeshi Kotani, Eiji Yamada, Yasutomo Kawabata
  • Patent number: 6072259
    Abstract: A stator core for a motor in which a member with rounded edges is used to prevent the electrical breakdown of the winding of a coil which may occur at a slot edge therein. End plates 18 are disposed on ends of the stator core 10 formed of laminated magnetic steel plates 12. Each of the end plates 18 has substantially the same pattern as each magnetic steel plate 1, viewed from the axis of the motor. The elongate surface 18a of the end plate 18 continues smoothly from the inner surface 16a of each of slots 16 to the rounded edge surface 18b. The rounded edge surface extends smoothly from the elongate surface 18a to the end surface 18c of the end plate 18. This structure can eliminate sharp edges from the fringe of the slot 16, thus preventing the electrical breakdown of a coated conductor 22 in the coil which may occur at the edges.
    Type: Grant
    Filed: May 11, 1998
    Date of Patent: June 6, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yasutomo Kawabata, Tetsuya Miura, Ryuji Toh, Masaru Hirako, Akio Fukui
  • Patent number: 6051946
    Abstract: The conventional technique can not detect the electrical angle of a synchronous motor in a sensor-less manner when a high torque is required under the condition of a low-speed operation of the motor. The direction that passes through the axis of rotation of the motor and causes a magnetic flux to pass through a permanent magnet is defined as a d axis, whereas the direction that is electrically perpendicular to the d axis in the plane of rotation of the motor is defined as a q axis. In the case where the motor is required to output a high torque, the technique of the present invention applies a predetermined detection voltage to the q axis and determines the electrical angle based on the ratio of electric currents flowing through the d axis and the q axis. Application of a negative voltage to the q axis relieves magnetic saturation occurring on the q axis under a high torque condition and thereby allows detection of the electrical angle.
    Type: Grant
    Filed: September 10, 1998
    Date of Patent: April 18, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Eiji Yamada, Yasutomo Kawabata
  • Patent number: 6037741
    Abstract: When there is a change in required torque, the prior art technique may cause the undesirably low accuracy in the sensor-free determination of the electrical angle. A motor controller of the present invention has the following configuration to control the operation of a synchronous motor, in which multi-phase alternating currents flow through coils to rotate a rotor. The motor controller includes an electrical angle determination unit, which applies a voltage for determination to the coils and determines the electrical angle of the rotor in a sensor-free manner, based on the electric currents flowing in response to the applied voltage for determination. The motor controller also has a torque control unit that applies a voltage for torque output to the coils, corresponding to the required torque.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: March 14, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Eiji Yamada, Yasutomo Kawabata
  • Patent number: 6025692
    Abstract: When a required torque increases under the condition of high-speed rotation, the conventional technique can not detect an electrical angle or control a synchronous motor in a sensor-less manner. The direction that passes through the rotating axis of the motor and makes a magnetic flux run through a permanent magnet is defined as the d-axis, whereas the direction that is electrically perpendicular to the d-axis in the rotational plane of the motor is defined as the q-axis. The technique of the present invention applies voltages to the d-axis and the q-axis based on an estimated electrical angle and solves voltage equations with the observed electric currents. The technique then calculates a correction amount of the electrical angle according to errors of the arithmetic operations and controls the motor. The arithmetic operations are carried out by varying the inductance according to the required torque of the motor.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: February 15, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Eiji Yamada, Yasutomo Kawabata
  • Patent number: 6025691
    Abstract: A synchronous motor control system which can freely regulate n-phase electric currents in a synchronous motor to control the characteristics of the synchronous motor. The synchronous motor control system can enhance the output torque per unit weight of a synchronous motor (40) simultaneously with reducing torque ripples. The waveform of three phase alternating currents is freely corrected over a range of +30 degrees from a specified electrical angle, at which a target phase current drawing a sine-wave curve reaches its peak value. It is assumed that this range of .+-.30 degrees corresponds to a range of 0 degree to 60 degrees. By way of example, the waveform is controlled to the peak value of the phase current in a range of 0 degree to 28 degrees. The correction of the phase current is carried out for the target phase which produces the primary magnetic flux of a revolving magnetic field.
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: February 15, 2000
    Assignees: Toyota Jidosha Kabushiki Kaisha, Kabushiki Kaisha Toyota Chuo Kenkyusho
    Inventors: Yasutomo Kawabata, Yoshiaki Taga, deceased, by Shigeo Taga, heir, by Takiko Taga, heir, by Tomoyo Taga, heiress, Masatoshi Uchida, Akihiko Kanamori, Yukio Inaguma, Toshinobu Arakawa
  • Patent number: 5998901
    Abstract: When power is output from an engine 50 to a crankshaft 56, a multiplying gear unit 57 attached to the crankshaft 56 increases a revolving speed but decreases a torque and transmits the increased revolving speed and the decreased torque to a rotating shaft 57e. A drive shaft 22 of a vehicle that cruises at a constant speed is generally driven at a higher revolving speed and a smaller torque than a driving point at which the engine 50 is driven with a high efficiency. The multiplying gear unit 57 converts the power output from the engine 50 to a power of high revolving speed and low torque. This structure decreases the amount of electrical energy transmitted between a clutch motor 30 and an assist motor 40 in the process of torque conversion by the clutch motor 30 and the assist motor 40 and thereby reduces an energy loss of both the motors 30 and 40. This effectively reduces the required capacities and size of the clutch motor 30 and the assist motor 40.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: December 7, 1999
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yasutomo Kawabata, Masanao Shiomi, Shigeru Matsuhashi
  • Patent number: RE38790
    Abstract: A power output apparatus 20 includes a clutch motor, an assist motor, and a controller. The clutch motor and the assist motor are controlled by the controller to enable the power output from an engine to a crankshaft 56, and expressed as the product of its revolving speed and torque, to be converted to the power expressed as the product of a revolving speed and a torque of a drive shaft and to be output to the drive shaft. The engine can be driven at an arbitrary driving point defined by a revolving speed and a torque, as long as the energy or power output to the crankshaft is identical. A desired driving point that attains the highest possible efficiency with respect to each amount of output energy is determined in advance. In order to allow the engine to be driven at the desired driving point, the controller controls the clutch motor and the assist motor as well as the fuel injection and the throttle valve position.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: September 6, 2005
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tomoharu Maeda, Yoshihide Nii, Shoichi Sasaki, Takeshi Kotani, Eiji Yamada, Yasutomo Kawabata