Oki Electric Industry Co., Ltd.

Nissan Motor Company Limited

Wisconsin Alumni Research Foundation

Other

Ricoh Company, Ltd.

Kawamura, Atsuo

Kensuke Sasaki

Shuko Kobayashi

Takashi Fukushige

Akihiko Nishiki

Robert Donald Lorenz

Takashi Katou

Yuichi Shibukawa

Atsuo Kawamura

Apoorva Athavale

Masaki Nakano

Takashi Kato

Hiroshi Saitoh

Kaoru Yoshino

Takaaki Tawada

Kenta Suzuki

Akira Fujimori

Hiroyuki Nakayama

Yusuke Zushi

Daiki Tanaka

Yukio Mizukoshi

Satoko Kutsuzawa

Brent S Gagas

Yasuhiro Kinbara

Tadashi Kasuya

Kohei Aoyama

A permanent magnet synchronous motor includes a stator, a rotor rotatable relative to the stator, and a magnetic structure with a low coercive force magnet and a high coercive force magnet that are arranged magnetically in series with respect to each other to define a pole-pair of the permanent magnet synchronous motor. A magnetization level of the low coercive force magnet is changeable by a stator current pulse such that a stator magnetomotive force at a rated current is equal to or larger than a product of a magnetic field strength for fully magnetizing the low coercive force magnet and a thickness of the low coercive force magnet.

Permanent magnet synchronous motor

A magnetization state control method for a variable magnetization machine, the method includes generating a flux linkage vector while changing a magnetization state of the variable magnetization machine such that a trajectory of the flux linkage vector has a curved clockwise trajectory on a dq-axis plane and a magnitude of the flux linkage vector temporally changes, with the dq-axis plane being a synchronous reference frame with a d-axis pointing in a direction of a permanent magnet flux and a q-axis being 90 degrees ahead of the d-axis in a rotational direction of a rotor.

Magnetization state control method and magnetization state control device

A permanent magnet synchronous motor includes a stator with a stator winding, a rotor with a rotor core rotatable relative to the stator, and a magnetic structure with at least one permanent magnet mounted to the rotor core. The magnetic structure produces a magnetic flux that flows between different magnetic poles of the magnetic structure through a main magnetic flux path that passes through the stator winding of the stator via an air gap and a leakage magnetic flux path that is located within the rotor core about an end portion of the permanent magnet near the air gap. The stator, the rotor and the magnetic structure being further configured to satisfy predetermined relationships in regards to the magnetic resistance of the main magnetic flux path and the leakage magnetic flux path, the magnetomotive force of the magnets and the stator.

A soft switching system DC-DC converter includes a switching element, a transformer or a reactor, and a controller configured to control a switching operation of the switching element; and carries out the switching operation of the switching element in a state that a voltage or a current to be applied to the switching element is zero. In a case where a required output value of the DC-DC converter is lower than the minimum output over which soft switching is established, the controller controls the operation of the switching element so that an operation period in which an output of the DC-DC converter becomes the minimum output or higher and a stop period in which the output becomes zero are alternately repeated.

DC-DC converter and control method thereof

A power supply device has a first power supply capable of storing and discharging electric power, a second power supply connected in series to the first power supply and capable of storing and discharging the electric power, an isolated DC-DC converter including a primary side terminal to which the first power supply is connected, and a secondary side terminal to which the second power supply is connected, and a power supply control unit that controls a voltage of the second power supply using the isolated DC-DC converter. A direct-current voltage outputted from the first power supply and the second power supply connected in series is inputted to a first inverter, converted into an alternating-current voltage by the first inverter, and then supplied to a vehicle drive motor.

Power supply device and method of controlling the same

Provided is an inverter module for use in an inverter-integrated motor, the inverter module being arranged at an axial end portion of a motor, the inverter module including trapezoidal power modules, each of which has a single-phase inverter circuit mounted thereon, and includes an electrical connection terminal for a power supply arranged on a short side thereof and an electrical connection terminal for the motor arranged on a long side thereof. A plurality of the trapezoidal power modules are arranged in an annular pattern so that the long side of the each of the plurality of the trapezoidal power modules faces toward an outer periphery, to thereby construct a polyphase inverter circuit.

Inverter module having trapezoidal shape for conversion of DC power to AC power

An electric component structure is provided with at least two electrical conductive parts, an insulator and a magnetic flux generating structure. The electrical conductive parts are arranged with an electric line of force existing between adjacent ones of the conductive parts. The insulator holds the conductive parts. The magnetic flux generating structure generates a magnetic flux with magnetic flux lines oriented in a direction different from a direction of the electric line of force existing between the adjacent ones of the conductive parts.

Electrical component structure

An image forming apparatus includes an image carrier, a cleaning device having a cleaning member that comes into contact with a surface of the image carrier, and a lubricant applying device provided on the downstream side of the cleaning member. The lubricant applying device includes a solid lubricant, a lubricant supply roller, and a trailing type lubricant smoothing blade that is provided on the downstream side of the lubricant supply roller, and comes into belly contact with the surface of the image carrier. After image carrier is stopped, constantly or under a predetermined condition, the surface of the image carrier is moved in a direction opposite to an image forming direction. The opposite movement distance is equal to or more than the shortest distance between a contact point between the lubricant supply roller and the image carrier and a contact point between the lubricant smoothing blade and the image carrier.

Image forming apparatus including a lubricant applying device configured to apply lubricant to an image carrier

An optical pulse time spreading apparatus wherein an optical splitter divides an input optical pulse into first to U-th input optical pulses; first to U-th optical pulse time spreaders respectively have the first to U-th input optical pulses input thereto and output first to U-th chip pulse sequences each consisting of N chip pulses from a first to an N-th chip pulse arranged in order on a time axis into which the input optical pulse is time-spread; and an interval between adjacent ones of unit FBGs arranged in a p-th optical pulse time spreader and a Bragg reflection wavelength of the unit FBGs in the p-th optical pulse time spreader are set such that spectra of the first to U-th chip pulse sequences are different from each other.

Encoding-decoding method, optical pulse time spreading apparatus, optical add-drop-multiplexer, and optical communication system

Super-structured fiber Bragg gratings (SSFBGs) of s optical pulse time spreaders are provided with N unit FBGs disposed starting from an input/output end in the order of first to N-th unit FBGs, where s is a parameter less than or equal to a parameter N, a natural number. The unit FBGs are configured such that the reflectivities of the unit FBGs placed from one end to the center of the SSFBG formed in an optical fiber are monotonically increased, while the reflectivities of the unit FBGs placed from the center to the other end of the SSFBG are monotonically decreased. The chip pulses in a pulse train are given relative phases such that the relative phase of the first chip pulse is equal to zero, the relative phase of the second chip pulse is equal to a phase difference d=2&#x3c0;{a+(n&#x2212;1)/N}, . . . , and the relative phase of the N-th chip pulse is equal to (N&#x2212;1)d. The parameter a is any real number satisfying the condition of 0&#x2266;a&#x3c;1.

Optical pulse time spreading apparatus and optical multiplex transmitting system with multiplexed channels and S/N ratio increased

An optical code division multiplexing signal generator provided with an optical pulse light source, a first encoder to an Nencoder, a first optical modulator to an Noptical modulator, and a first optical circulator to an Noptical circulator. The first optical circulator inputs an input optical pulse train to a first encoder, and inputs a first encoded optical pulse train output by Bragg reflection from the first encoder to the first optical modulator. The koptical circulator inputs an input (k&#x2212;1)optical pulse train which has passed through the (k&#x2212;1)encoder to a kencoder, and inputs a kencoded optical pulse train output by Bragg reflection from the kencoder to the koptical modulator. Herein k takes all integers from 2 to N, and N is a positive integer of 2 or more.

Optical code division multiplex signal generator

An optical pulse time spreading device includes S optical pulse time spreading elements that spread input optical pulses into trains of (N&#xd7;j) chip pulses, where j is an integer greater than zero, S is an integer greater than one, and N is an integer equal to or greater than S. In the chip pulse trains output by the n-th optical pulse time spreading element (n=1, 2, . . . , S), the light in successive chip pulses is shifted in phase by successive integer multiples of the quantity 2&#x3c0;{a+(n&#x2212;1)/N}, where a is an arbitrary constant (0&#x2266;a&#x3c;1). In an optical code-division multiplexing system, this optical pulse time spreading device produces an autocorrelation wave with a high energy and a high signal-to-noise ratio.

Optical pulse time spreading device

A phase control arrangement has a structure in which a Superstructured fiber Bragg Grating (SSFBG)has fifteen unit Fiber Bragg Gratings (FBGs) arranged in series in a waveguide direction. The SSFBGis fixed to the core of an optical fiberthat includes a coreand cladding. The difference &#x394;n between the maximum and minimum of the effective refractive index of the optical fiber is 6.2&#xd7;10. The phase difference of Bragg reflected light from two unit diffraction gratings that adjoin one another from front to back and provide equal code values is given by 2&#x3c0;M+(&#x3c0;/2), where M is an integer. Further, the phase difference of the Bragg reflected light from two unit diffraction gratings that adjoin one another from front to back and provide different code values is given by 2&#x3c0;M+(2N+1)&#x3c0;+(&#x3c0;/2) where M and N are integers. The ratio P/W between the peak value P and the subpeak value W of the autocorrelation waveform, and the ratio P/C between the peak value P of the autocorrelation waveform and the maximum peak value C of the cross correlation waveform are both large.

Optical pulse time spreader and optical code division multiplexing transmission device

The present invention is an optical pulse time spreading device comprising a plurality of optical pulse time spreaders that output an input optical pulse as a series of chip pulses stream that are sequentially arranged time-spread on a time axis in accordance with optical phase code. Each of the optical pulse time spreaders comprises phase control means that supplies a phase difference between adjacent chip pulses. Identification parameters are introduced to realize channel discrimination by changing the phase difference conditions supplied between adjacent chip pulses for each of the phase control means. The phase control means have a structure in which an SSFBG is fixed to the core of the optical fiber, for example. The SSFBG has unit FBGs that are arranged in series in the waveguide direction of the core. The code values of the optical phase code established for the phase control means correspond each one-on-one with each of the unit FBGs.

An FBG system with lower power supplied to a temperature controller, while allowing for precise temperature control of an FBG grating. The FBG system includes a high temperature FBG-mounting structure and a low temperature FBG-mounting structure, and a housing containing them. The high temperature FBG-mounting structure includes an FBG module and a thermo module. The temperature of the FBG in the FBG module may be made higher than the environmental temperature by supplying heat from a heat-conducting portion to the thermo module. The low temperature FBG-mounting structure includes an FBG module and a thermo module. The temperature of the FBG in the latter FBG module may be made lower than the environmental temperature by supplying heat from the latter thermo module to the heat-conducting portion. The FBG-mounting structures are provided in parallel on the inner bottom surface of the heat-conducting portion, part of the housing.

Growing community of inventors

Kanagawa, Japan

Kensuke Sasaki