Patents Assigned to Japan Servo Co.
  • Publication number: 20070090699
    Abstract: A multi-polar rotary machine comprises a cylindrical outer rotor arranged concentrically with the stator and with an air gap therebetween. The stator has two spaced stator elements and a ring shaped permanent magnet held between the stator elements and magnetized so as to form N and S poles in the axial direction of the stator. Small axially separated stator teeth A and A and B and B are formed on the outer peripheral surface of the spaced stator elements. Stator windings for A phase and B phase are wound around the respective stator elements. The small stator teeth A, A, B and B are circumferentially shifted from corresponding small rotor teeth by a ΒΌ pitch of the small stator teeth, respectively. Each of the stator and rotor is formed of pressed powder comprising a soft magnetic material at least one of a resin and an inorganic material.
    Type: Application
    Filed: November 20, 2006
    Publication date: April 26, 2007
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Kazuo Ohnishi, Shoji Ohiwa, Yasuaki Motegi
  • Patent number: 7207774
    Abstract: A centrifugal fan includes a scroll casing having an almost cylindrical shape. The casing consists of first and second casings. The first casing constitutes one base wall and a part of a side circumferential wall of a cylinder, and the second casing constitutes the other base wall and the remaining part of the side circumferential wall. An air inlet is formed on a center portion of the base wall of the first casing, and an exhaust port that is formed on the side circumferential wall. An impeller having many blades and a motor for driving the impeller are contained in the casing. A cylindrical partition that is formed on the inside of the base wall of the second casing over the entire circumference. The partition consists of a high partition formed in at least a region close to the exhaust port and a low partition formed in the other region.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: April 24, 2007
    Assignee: Japan Servo Co., Ltd.
    Inventors: Yoshio Kashiwazaki, Youichi Nagata
  • Publication number: 20070022597
    Abstract: A first part formed of a first material is positioned to a second part formed of a second material, which is different from the first material in degree of modification due to environmental variation, by contacting surfaces of the first and second parts. At least three projections are formed on the contact surface of the first part along a circle whose center is coincident with a reference point. Grooves are formed on the contact surface of the second part so that the respective projections are fitted therein and that have wall surfaces to which the projections can contact at the inner and outer sides of the projections. The width of the grooves is determined so that the projections contact the inner or outer wall surface of the grooves even when the first and second parts deform in different degrees due to environmental variation.
    Type: Application
    Filed: July 24, 2006
    Publication date: February 1, 2007
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Ayako Shimura, Junji Rokunohe, Naoyuki Kanamori
  • Patent number: 7145278
    Abstract: A permanent magnet type three-phase stepping motor that is simple in construction, with reduced vibration, a reduced unbalanced force in the radial direction, and high torque that can be manufactured at a low cost.
    Type: Grant
    Filed: April 28, 2005
    Date of Patent: December 5, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventor: Masafumi Sakamoto
  • Publication number: 20060267426
    Abstract: An induction motor has a gear connected to an output shaft of the motor, a ratchet wheel having a claw for preventing the reverse rotation of the gear, and an urging device. The urging device urges the ratchet wheel so that an end surface of a tip end of the claw of the ratchet wheel is brought into contact with a tooth face facing a reverse rotary direction of the gear so as to prevent the reverse rotation of the gear. A contact angle formed by the end surface of the tip end of the claw and a center line of the tooth of the end surface of gear preferably is set equal to a pressure angle of the gear.
    Type: Application
    Filed: May 30, 2006
    Publication date: November 30, 2006
    Applicant: Japan Servo Co., Ltd.
    Inventors: Toshio Maehara, Eiji Kuroda
  • Patent number: 7132769
    Abstract: A terminal arrangement of a motor has a terminal base formed with a plurality of terminal pins, the terminal base being fixed detachably on a stator iron core of a motor, terminal pins formed on bobbins, connected electrically with windings wound around the bobbins, a printed circuit board arranged on the stator iron core so as to connect electrically the terminal pins formed on the bobbins with the terminal pins formed on the terminal base, and an end bracket arranged so as to cover the printed circuit board. A hole is formed in the stator iron core, and an earth electrode is projected from the terminal base, and inserted into the hole so as to be connected electrically with the stator iron core, the earth electrode being connected electrically to one of the terminal pins formed on the terminal base. A capacitor motor has a motor having a stator iron core, and a phase advancing capacitor fixed detachably on the stator iron core.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: November 7, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Keiji Uchida, Hiroyuki Tanaka, Hitoshi Ishii, Yasushi Niwa, Toshio Kobayashi
  • Publication number: 20060222491
    Abstract: A centrifugal fan includes a scroll casing having first and second flat base walls, and a circumferential side wall. An air inlet is formed on a center portion of the first base wall and an exhaust port is formed on the circumferential side wall. An airflow correction mechanism that forms smooth airflow when an impeller rotates is provided. The mechanism has an annular rib that is formed on the inside surface of the first base wall so as to be jutted to the side of the second base wall and to be concentric with the rotating shaft, and a recess portion that is formed on every blade of the impeller so that the annular rib is inserted therein with a predetermined gap. The annular rib and the recess portion are configured to change the direction of airflow directed to the air inlet back to a space between the blades.
    Type: Application
    Filed: March 30, 2006
    Publication date: October 5, 2006
    Applicant: JAPAN SERVO CO., LTD.
    Inventor: Ryuichi Shimada
  • Patent number: 7088072
    Abstract: A stepping motor control system according to the present invention includes a counting mechanism for counting the number of steps of the pulse train command, a latch mechanism for holding a counting value of the counting mechanism with a latch signal and finding a position command, a reference signal generating mechanism for generating the latch signal and a reference clock signal, a first calculating mechanism for calculating a pulse spacing of the pulse train command with the reference clock signal, and a second calculating mechanism for calculating a time interval from generation of the pulse train command to generation of the latch signal with the reference clock signal. In the stepping motor control system, the position command is corrected using command pulse spacing information calculated by the first calculating mechanism and time difference information calculated by the second calculating mechanism.
    Type: Grant
    Filed: October 27, 2005
    Date of Patent: August 8, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Yoshifumi Kuwano, Hiroaki Taka, Akio Takemori
  • Publication number: 20060171802
    Abstract: The present invention is aimed to pursue both an inhibition of a noise when operating by maintaining stiffness of a blade, and a more effective cooling for responding to an increase of heat generation of internally mounted components, with needs for a smaller and high-performance device. A hub for connecting the blades is composed of an outer circular hub partially covering an outer peripheral edge of the blade and an inner circular hub partially covering an inner peripheral edge of the blade, the hubs concentrically formed, and an opening is provided between the two inner and outer circular hubs.
    Type: Application
    Filed: January 26, 2006
    Publication date: August 3, 2006
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Yoshio Kashiwazaki, Youichi Nagata
  • Publication number: 20060171803
    Abstract: A centrifugal fan includes a scroll casing consisting of first and second flat base walls, a circumferential side wall. An air inlet is formed on the first base wall, an exhaust port is formed on the side wall. A backflow prevention mechanism is arranged in the airflow path to prevent backflow from the exhaust port during fan halting. The mechanism has a flap that is rotatably supported by the first base wall and its rotation axis is inclined with respect to the vertical direction so that the flap shuts the airflow path under its own weight in a horizontal-use position where the rotating shaft of the motor is horizontal. The flap is inserted into a slit from the outside and is held by a stopper plate. A protrusion, which contacts with the rim of the flap when the flap shuts the airflow path, is formed inside the walls.
    Type: Application
    Filed: January 26, 2006
    Publication date: August 3, 2006
    Applicant: JAPAN SERVO CO., LTD.
    Inventor: Morio Senba
  • Patent number: 7068001
    Abstract: A motor control system according to the present invention comprises a magnetic encoder including a magnetic drum fixed to an output shaft of a motor and a magnetic sensor provided against a periphery of the magnetic drum through a space, an angle calculating unit for calculating a rotational angle of the motor from an output of the magnetic encoder, an angle estimating unit for estimating the rotational angle, an error angle calculating unit for finding an error angle from an calculated angle calculated by the angle calculating unit and an estimated angle estimated by the angle estimating unit, an error-correction value calculating unit for calculating from the error angle an error-correction value that corresponds to the rotational angle, a correction calculating unit for calculating a correction angle or a correction speed from the calculated angle and the error-correction value, and a motor operation controlling unit for outputting to an inverter a voltage command value that corresponds to the correction a
    Type: Grant
    Filed: July 22, 2005
    Date of Patent: June 27, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Yoshihiro Okumatsu, Yasuo Matsuda, Shoji Ohiwa
  • Patent number: 7068007
    Abstract: A stepping motor driving system and process according to the present invention controls a switching element in such a manner that motor supply current is passed through a motor coil until a coil current detection value reaches an upper limit set point, motor reflux current is passed through the motor coil until predetermined time elapses since the motor supply current begins to flow after the coil current detection value reached the upper limit set point, motor regeneration current is passed through the motor coil until the coil current detection value reaches a lower limit set point when predetermined time has passed, and motor reflux current is passed through the motor coil until predetermined time elapse since the motor regeneration current begins to flow after the coil current detection value reached the lower limit set point.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: June 27, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventor: Charles Simson Silitonga
  • Patent number: 7066231
    Abstract: A wasteless type lamination system comprises a first transfer device for transferring along a first transfer path a continuous laminate film; a cutter for cutting the continuous laminate film in a predetermined length, provided beside the first transfer path at the downstream of the first transfer device; a second transfer device for transferring along the first transfer path a cut laminate film; a film detection sensor for detecting a leading edge of the continuous laminate film, provided beside the first transfer path at the downstream of the cutter; a card transfer device for transferring a card along a second transfer path; and a thermocompression bonding device for laminating the cut laminate film to the card. The continuous laminate film is moved backward from the cutter by a predetermined distance by the first transfer device before or after cutting action of the cutter.
    Type: Grant
    Filed: March 6, 2003
    Date of Patent: June 27, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Naotaka Sasaki, Shunichi Kawamata, Kenji Sugaya, Hideaki Ito
  • Patent number: 7053584
    Abstract: Disclosed is a driving device for a motor such as a stepping motor etc. for controlling an angle and a speed of the motor, wherein the driving device comprises exciting current detectors for detecting exciting currents of motor windings of the motor, an exciting current amplitude computation means for computing an exciting current amplitude value or the square of the exciting current amplitude value from exciting current detection values detected by the exciting current detectors, and a voltage impression unit for impressing voltages at values corresponding to a deviation value of the exciting current amplitude value and the current amplitude command or a deviation value of the square of the exciting current amplitude value and the square of the current amplitude command to the motor windings.
    Type: Grant
    Filed: October 1, 2003
    Date of Patent: May 30, 2006
    Assignee: Japan Servo.Co., Ltd.
    Inventors: Hiroaki Taka, Yoshifumi Kuwano, Akio Takemori, Yukinari Takahashi
  • Patent number: 7037092
    Abstract: A roller pump comprises a pump housing having a cylindrical inner surface, a rotor fixed to a drive shaft placed at the central portion of the pump housing, rollers provided around the rotor and a driver for driving the drive shaft through a reduction gear. The rollers press an elastic tube installed between the rollers and the inner surface of the pump housing to transfer a liquid in the elastic tube by rotation of the rotor. The pump housing and the reduction gear are integrated into one body and an output shaft of the reduction gear is fixed to the drive shaft of the rotor. A stepping motor is used as the driver. A part of the inner surface of the pump housing is composed of a semicircle, another part of the inner surface is composed of a partial circle of which center is shifted from the center of the semicircle.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: May 2, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Yoshihisa Kagawa, Kazuhide Yamazaki, Seiji Kojima
  • Publication number: 20060082241
    Abstract: An electric rotating machine having permanent magnets comprising a rotor having a plurality of permanent magnets, a stator iron core disposed in opposite relation with the rotor, and a stator winding wound around the stator core, wherein the stator core is constituted by a yoke and a plurality of teeth portions disposed to the yoke. The teeth portions are projected towards the inner periphery of the rotor. The teeth portions is made of amorphous magnetic material.
    Type: Application
    Filed: September 22, 2005
    Publication date: April 20, 2006
    Applicants: Japan Servo Co., LTD., Hitachi Powdered Metals Co., Ltd., Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Metals Ltd.
    Inventors: Yuji Enomoto, Haruo Koharagi, Motoya Ito, Katsuyuki Yamazaki, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara, Masahiro Mita
  • Patent number: 7029229
    Abstract: An axial flow fan of high efficiency and low noise level is provided. The fan includes a motor, an impeller having a plurality of blades around a hub fitted to the motor, and a fan casing having an air inlet on one side and an air outlet on the other, wherein a radial position with a maximum setting angle in a blade section, and a radial position with a contour of a leading edge portion in a fluid flowing direction forming a projecting apex in the flowing direction are located between 60% and 80% of the outside diameter of the impeller.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: April 18, 2006
    Assignees: Hitachi, Ltd., Japan Servo Co., Ltd.
    Inventors: Taku Iwase, Kazuyuki Sugimura, Taro Tanno
  • Publication number: 20060071562
    Abstract: A stator core having twelve stator poles, coils wound around the stator poles, and a hybrid type rotor are included. The stator poles inwardly and radially extended from an annular yoke portion. Each of the respective stator poles has inductors of the same number. The coils are connected so that a pair of the stator poles being substantially symmetric with respect to a point are excited in opposite polarities. The rotor is arranged with a predetermined air gap with respect to the inductors, the rotor has a pair of rotor cores each of which has rotor teeth facing to the inductors and a permanent magnet magnetized in the axial direction sandwiched therebetween. The angles between inductors at the corresponding positions of adjacent stator poles are defined by repeating three sets of angular distributions each of which includes three times of 29.1 degrees and one time of 32.7 degrees when a number of rotor teeth equals 100.
    Type: Application
    Filed: October 4, 2005
    Publication date: April 6, 2006
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Masafumi Sakamoto, Akira Tozune
  • Patent number: 7023202
    Abstract: The invention relates to a magnetic rotary position sensor that detects the absolute position of a rotation angle as an electric output in a non-contact state with magneto-electric transducers for converting a magnetic flux variation into a voltage. The magnetic rotary position sensor of the invention includes a cylindrical yoke, semi-cylindrical first and second magnets, and magneto-electric transducers. Here, the first and second magnets are disposed on the inside of the yoke to face to each other, and are magnetized in a manner that the N-pole and S-pole face to each other.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: April 4, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Hiroshi Hagino, Atushi Yamamoto, Takanobu Igarashi, Masahiro Horiguchi
  • Patent number: 7023165
    Abstract: A stepping motor control apparatus in accordance with the present invention comprises: a current detection unit that detects phase currents flowing into a stepping motor; an equivalent model-of-motor arithmetic unit that includes a coefficient multiplication block which performs multiplication using a coefficient ka?=Ts/? as a multiplier, a coefficient multiplication block which performs multiplication using a coefficient kb?=?/(Ts+?) as a multiplier, and a coefficient multiplication block which performs multiplication using a coefficient kg?=I0/E0 as a multiplier, and that calculates an estimated angle of excitation; a current control unit that controls an exciting current on the basis of the estimated angle of excitation, an angle command, and the phase currents detected by the current detection unit; and a variable voltage inverter that applies phase voltages to phase windings included in the stepping motor according to outputs of the current control unit.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: April 4, 2006
    Assignee: Japan Servo Co., Ltd.
    Inventors: Yoshifumi Kuwano, Hiroaki Taka, Akio Takemori