Patents Assigned to Japan Servo Co.
  • Patent number: 7845180
    Abstract: An automatic icemaker of the present invention includes a control box, an ice-making tray supporting frame rotatably supported and rotated by the control box, at least one ice-making tray rotatably supported by the ice-making tray supporting frame, a rotation limiter fixed to the ice-making tray supporting frame and limiting the rotation of the ice-making tray, a stopper fixed to the control box, and a projection provided to the ice-making tray. Irregularities are provided to at least one of the contact surfaces of the stopper and projection.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: December 7, 2010
    Assignee: Japan Servo Co., Ltd.
    Inventors: Kenji Sugaya, Yoshihisa Kagawa, Hideaki Ito
  • Patent number: 7728543
    Abstract: A stepping motor controlling device according to the present invention includes lead angle computing means which computes a lead angle according to the load torque current deviation of the stepping motor, adding means which adds an angle command to the lead angle to determine a winding exciting angle and voltage applying means which applies a voltage according to the winding exciting angle to the stepping motor.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: June 1, 2010
    Assignee: Japan Servo Co., Ltd.
    Inventors: Akio Takemori, Yoshifumi Kuwano, Hiroaki Taka, Yoshitaka Iwaji
  • Patent number: 7714466
    Abstract: To realize reduction in vibration and noise while utilizing reluctance torque, a rotating electrical machine includes: a rotor having permanent magnets disposed in a cylindrical surface coaxial with a rotary shaft; and a stator having an annular stator core disposed coaxially with the rotary shaft, and a annular coil for magnetizing the stator core. The stator core has an annular part covering the annular coil, claws disposed at equal intervals in an inner radius surface of the annular part and extending axially, and magnetic gaps formed between neighboring claws. The number of claws is equal to the number of permanent magnets, and magnet flux in a direction orthogonal to a center axis of the magnetic pole of the permanent magnet at right angles in electric angle is larger than magnetic flux in the center axis direction generated between neighboring permanent magnets. Metal interpoles are provided between neighboring permanent magnets.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: May 11, 2010
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powdered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Masashi Kitamura, Fumio Tajima, Shigeru Kakugawa, Yuji Enomoto, Motoya Ito, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara
  • Patent number: 7714475
    Abstract: In a multiple phase claw pole type motor which includes: a plurality of claw poles including a claw portion extending in an axial direction and having a magnetic pole surface facing a rotor in a state of being separated from the rotor by a small gap, a radial yoke portion extending radially outwardly from this claw portion, and an outer peripheral yoke extending from this radial yoke portion in the same direction as the direction of extension of the claw portion; a stator core formed by alternately placing the claw poles in a circumferential direction so that a distal end of each claw portion faces the outer peripheral yoke of an adjacent one of the claw poles; and a stator constructed by sandwiching an annular coil with the adjacent claw poles of this stator core, a multiple phase claw pole type motor characterized in that the claw poles are formed by compacting a magnetic powder and are formed of a magnetic compact having a DC magnetizing property of its flux density becoming 1.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: May 11, 2010
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powdered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Kenji Miyata, Chio Ishihara, Ryoso Masaki, Yasuaki Motegi, Kouki Isozaki, Tadashi Sato
  • Patent number: 7713036
    Abstract: A liquid pumping apparatus comprising a rotor housing, a rotor having at least one roller, to be rotated by a prime mover, an inner periphery wall of the rotor housing, a flexible tube to be inserted into a gap formed between the rotor and the inner periphery wall and squeezed when the rotor is rotated so as to transfer a liquid fed into the tube, and a deformable guide for guiding the flexible tube in a moving path of the roller. At least one portion of the inner periphery wall is movable so as to approach or separate from the rotor.
    Type: Grant
    Filed: September 23, 2005
    Date of Patent: May 11, 2010
    Assignee: Japan Servo Co., Ltd.
    Inventors: Seiji Kojima, Kenji Sugaya
  • Patent number: 7665316
    Abstract: Disclosed is an automatic icemaker has a rotatably supported ice making portion having first and second ice making trays arranged in a back-to-back manner, a motor for rotating the ice making portion, a first and a second temperature detecting sensors for detecting the temperature of the first and second ice making tray or the temperature of ice within a compartment of the first and second ice making tray, and a signal processor for controlling the motor to turn over the ice making portion after the temperature of the first or second ice making tray, or the temperature of ice within a compartment of the first or second ice making tray, looking upward, detected by the first temperature detecting sensor or the second temperature detecting sensor has become stabilized in the vicinity of 0° C.
    Type: Grant
    Filed: May 12, 2006
    Date of Patent: February 23, 2010
    Assignee: Japan Servo Co., Ltd.
    Inventors: Hideaki Ito, Naotaka Sasaki, Kenji Sugaya
  • Patent number: 7649298
    Abstract: A claw teeth type electric rotary machine comprises a stator including an annular core with claws formed from a powder core and an annular coil installed inside the annular core, and a rotor rotatably positioned inside the stator. An inner edge of the annular core is provided with plural claw poles which are protruded at a predetermined interval in a circumferential direction and extended in an axial direction of the annular core so as to alternately meshes with each other. The stator comprises the annular core with claws, the annular coil, and a molded nonmagnetic potting material filled between the annular core with claws and annular coil, so that the annular core with claws and annular coil are integrated with the molded potting non-magnetic material.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: January 19, 2010
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Masashi Kitamura, Ryoso Masaki, Katsuyuki Yamazaki, Shoji Ohiwa, Yasuaki Motegi, Kazuo Asaka, Chio Ishihara
  • Patent number: 7626301
    Abstract: An electric rotating machine having permanent magnets having 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 are made of amorphous magnetic material.
    Type: Grant
    Filed: September 22, 2005
    Date of Patent: December 1, 2009
    Assignees: 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 Yamasaki, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara, Masahiro Mita
  • Patent number: 7622838
    Abstract: An axial fan motor comprising: a fan having a rotating shaft and composed of a hub and a plurality of vanes provided around the hub, the fan rotating to generate an air flow; a stator substrate set comprising a stator core, which drives the fan, an insulator, and a substrate; and a venturi having a sleeve, into an inner peripheral side of which a bearing is inserted to support the rotating shaft and to an outer peripheral side of which the stator core is fixed, the venturi being formed on one side thereof with an air suction opening and on the other side thereof with an air discharge mouth, wherein a space is provided between the stator core and the sleeve.
    Type: Grant
    Filed: April 9, 2007
    Date of Patent: November 24, 2009
    Assignee: Japan Servo Co., Ltd.
    Inventors: Masanori Watanabe, Taku Iwase, Osamu Sekiguchi, Taro Tanno, Yoshihiko Kato, Tetsuya Hioki
  • Patent number: 7605517
    Abstract: A claw pole type rotating electric machine includes first and second claw cores which are disposed on a ring shaped ring yoke portion and a plurality of claw magnetic poles which extend in the axial direction are provided, and stator cores are formed by meshing of the claw magnetic poles with each other, and the stator is formed by holding the ring coils on the outer circumference side of the claw magnetic poles, wherein the first and second claw cores are formed by powder cores, the radial direction thickness of the claw magnetic pole is 2 mm or more, a flat surface is formed perpendicular to the axial direction at the end extending in the axial direction of the claw magnetic pole, a ejection taper in the circumference direction of the claw magnetic pole is formed in the range of 10 degrees or less, and the ratio of the axial direction length of the claw magnetic pole and the axial direction thickness of the ring yoke portion is no more than 5:1.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: October 20, 2009
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Shoji Ohiwa, Ryozo Masaki, Chio Ishihara
  • Patent number: 7592734
    Abstract: A three-phase permanent magnet brushless motor comprises a stator having three-phase windings, and a rotor having a permanent magnet with a plurality of poles for serving as a field magnet. The stator comprises a stator core which includes a powder core that is compacted at a high density in at least teeth thereof. A combination of the number of magnetic poles of the rotor with the number of slots of the stator satisfies a condition that a least common multiple of the number of slots and the number of magnetic poles is 60 or more in a region in which the number of magnetic poles is 16 or less, and the number of slots is 12 or less. The powder core is made by compacting magnetic powders to have a green density of 7.5 g/cm3 or higher.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: September 22, 2009
    Assignees: Hitachi Industrial Equipment System Co., Ltd., Japan Servo Co., Ltd., Hitachi Powered Metals Co., Ltd.
    Inventors: Yuji Enomoto, Akeshi Takahashi, Motoya Ito, Ryoso Masaki, Katsuyuki Yamazaki, Masahide Yamazaki, Masashi Kitamura, Chio Ishihara, Kazuo Asaka, Shoji Ohiwa, Yasuaki Motegi
  • Patent number: 7567044
    Abstract: A braking device for an electrically driven rotor comprises a drive signal generating circuit for an electrically driven rotor, an output stage, a motor for the electrically driven rotor, driven by the output stage, and a monitor circuit for detecting interruption of an electric power supply for the motor. The output stage has a MOSFET of an upper stage side and a MOSFET of a lower side, and a diode inserted between a gate of the MOSFET of the lower stage side and the electric power supply. An electromagnetic brake is generated and applied on the electrically driven rotor when the MOSFET of the upper stage side is turned OFF and the MOSFET of the lower stage side is turned ON by a control signal from the monitor circuit, and an exciter coil of the motor is shorted when the electric power supply is interrupted.
    Type: Grant
    Filed: March 21, 2007
    Date of Patent: July 28, 2009
    Assignee: Japan Servo Co., Ltd.
    Inventor: Shuichi Matsuhashi
  • Publication number: 20090108713
    Abstract: An outer rotor type hybrid stepping motor includes a stator, a rotor, a magnet disposed axially in the stator or the rotor, a stator core disposed inwardly from a gap between the stator and rotor, and a stator winding on the stator core. The rotor is disposed outside the gap. The magnet has an axial cross sectional area A. The residual magnetic flux density of the magnet is Br, and a total of magnetic fluxes exiting axially from the surface is A×Br. A gap average magnetic flux density, determined by dividing A×Br by the top cross sectional area small teeth poles on the rotor is Bg; pitch of the teeth is ?; and tooth width is Tw. Average magnetic flux density Bg, tooth pitch ?, and tooth width Tw are determined by the equation K=1/(?×Bg×Tw/?), with the coefficient k in a range of 0.56-0.66 (1/T).
    Type: Application
    Filed: October 29, 2008
    Publication date: April 30, 2009
    Applicant: Japan Servo Co. Ltd.
    Inventors: Yuji ENOMOTO, Kenji Miyata, Yasuaki Motegi, Shoji Ohiwa
  • Patent number: 7487645
    Abstract: An automatic icemaker according to the invention can be disposed in one part of a freezer and automatically make ice pieces, and is provided with temperature distribution forming means which forms a temperature distribution in which freezing progresses from the open side of ice partitions of an ice-tray and is completed near the bottom side of the ice partitions.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: February 10, 2009
    Assignee: Japan Servo Co., Ltd.
    Inventors: Naotaka Sasaki, Kenji Sugaya, Hideaki Ito
  • Patent number: 7470108
    Abstract: In an axial flow fan, for reducing fluid noise and further reducing the noise by suppressing solid-conveyed noise (structure-borne noise) generated by the vibration of an electric motor or the like, the axial flow fan is equipped with a propeller, a motor for driving the propeller, and a venturi portion disposed on the outer circumference side of the propeller and provided on its inner circumferential side with a bellmouth through which an air flow generated by the revolution of the propeller passes, wherein the bellmouth has an intake portion whose diameter contracts in a curved shape in the direction of the air flow, a cylindrical portion having a cylindrical shape, and a discharge portion whose diameter slantingly expands in the direction of the air flow.
    Type: Grant
    Filed: April 20, 2005
    Date of Patent: December 30, 2008
    Assignee: Japan Servo Co., Ltd.
    Inventors: Masanori Watanabe, Taku Iwase, Shouichi Kawamata, Osamu Sekiguchi, Taro Tanno
  • Patent number: 7446441
    Abstract: An outer rotor type hybrid stepping motor including a stator, a rotor, a magnet disposed axially in either the stator or rotor, a stator core disposed inward from a gap formed between the stator and rotor, the rotor disposed outside the gap, and a stator winding wound around the stator core. The outer rotor type hybrid stepping motor has a cross-sectional area A in the axial direction of the magnet, a gap portion diameter D, a lamination thickness of the stator core in the axial direction L and a residual magnetic flux density of the magnet Br. The lamination thickness of the stator core in the axial direction L and the residual magnetic flux density Br are determined according to the equation D×L/A=k×Br with the condition that coefficient k is kept in a range of 0.56-0.66(1/T). The resulting optimized design parameters for L and Br provide a reduction in size of the outer rotor type hybrid stepping motor, a high output and a high resolution.
    Type: Grant
    Filed: August 19, 2004
    Date of Patent: November 4, 2008
    Assignee: Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Kenji Miyata, Yasuaki Motegi, Shoji Ohiwa
  • Publication number: 20080237000
    Abstract: A micro switch is mounted onto a mounting base attached to a controller of an automatic icemaker. The micro switch generates a signal for controlling the amount of water to be filled in an ice tray. The micro switch is fixed to the mounting base by the first fixing member and the second fixing member. The first fixing member is inserted through a mounting hole formed in a case of the micro switch. The second fixing member is arranged on a surface of the mounting base on an opposite side of a surface mounted with the micro switch, and is fixed to the first fixing member.
    Type: Application
    Filed: January 17, 2008
    Publication date: October 2, 2008
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Toshio Maehara, Eiji Kuroda, Yoshitaka Yokoi
  • Publication number: 20080157634
    Abstract: A motor includes a rotor portion including a shaft and a rotor magnet rotatable about a center axis, an armature arranged opposite to the rotor magnet to generate a torque therebetween, a circuit board arranged below the armature in an axial direction substantially parallel to the center axis and including a control circuit controlling rotation of the rotor portion, and a base portion including a bearing holder which supports the armature on its outer side surface and the shaft on its inner side surface via a bearing member. The armature is pressed against the bearing holder in the axial direction with an elastic member.
    Type: Application
    Filed: March 3, 2008
    Publication date: July 3, 2008
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Osamu SEKIGUCHI, Taro TANNO, Yoshihiko KATO, Tetsuya HIOKI, Asahi HIGO
  • Patent number: 7385321
    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 ? 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, ?, B and B are circumferentially shifted from corresponding small rotor teeth by a ¼ 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: Grant
    Filed: November 20, 2006
    Date of Patent: June 10, 2008
    Assignee: Japan Servo Co., Ltd.
    Inventors: Kazuo Ohnishi, Shoji Ohiwa, Yasuaki Motegi
  • Patent number: D572660
    Type: Grant
    Filed: April 14, 2006
    Date of Patent: July 8, 2008
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Japan Servo Co., Ltd., Hitachi Powdered Metals Co., Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Kazumasa Ide, Masashi Kitamura, Ryoso Masaki, Katsuyuki Yamazaki, Shoji Ohiwa, Yasuaki Motegi, Kazuo Asaka, Chio Ishihara