Patents Assigned to NSK Ltd.
  • Patent number: 7268459
    Abstract: The electric power steering apparatus includes a brushless motor as an electric motor. The motor has a rotor and a stator 34. The stator 34 includes: a back core BY; a plurality of teeth TS disposed along the circumference of the back core protruding from the back core BY toward its radial center and forming slots SL therebetween; and an exciting coil 38 wound around each of the teeth TS. Each of the slots SL is filled with a resin material. The back core BY is partially press-fitted into a yoke 21 so that the outer surface of the back core BY comes partially into contact with the inner surface of the yoke 21 along their circumferences.
    Type: Grant
    Filed: July 13, 2005
    Date of Patent: September 11, 2007
    Assignee: NSK Ltd.
    Inventors: Takashi Baba, Manabu Okamura, Sachio Nakayama
  • Patent number: 7267488
    Abstract: A grease-lubricated rolling bearing has an outer ring having an outer ring race in an inner peripheral surface thereof, an inner ring having an inner ring race on an outer peripheral surface thereof, rolling elements rollably provided between the outer ring race and the inner ring race, and a grease supply element for supplying an additional grease in the rolling bearing. The amount of the additional grease to be supplied at a time is predetermined to be from 0.1 to 4% of the volume of space in the bearing.
    Type: Grant
    Filed: February 8, 2005
    Date of Patent: September 11, 2007
    Assignee: NSK Ltd.
    Inventors: Saburo Azumi, Yasushi Morita, Naoki Matsuyama, Takaaki Anzai
  • Patent number: 7267487
    Abstract: There is disclosed a bearing unit (5, 5a) for a wheel comprising a stationary race (6) having stationary race track surfaces (11a, 11b) on a peripheral surface on the stationary side thereof to be supported and fixed by a suspension system in its used state, a rotating race (8) having rotating race track surfaces (14a, 14b) on a peripheral surface on the rotating side so as to fix a wheel and a braking rotating member in its used state, and a plurality of balls (17) provided between the rotating race tracks and the stationary race tracks, wherein a standard value for the mutual difference in diameter between these balls is not more than 1.0 ?m.
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: September 11, 2007
    Assignee: NSK Ltd.
    Inventor: Hiroaki Ishikawa
  • Publication number: 20070206892
    Abstract: A grease composition having an apparent viscosity at ?30° C. of 5 to 200 Pa·s is sealed in a rolling bearing which retains a plurality of rolling elements between an inner ring and an outer ring in such a way that the rolling elements can freely roll. Thereby, there is provided a rolling bearing which has a satisfactory lubricating performance and generates less abnormal noise even under a low temperature of around ?40° C.
    Type: Application
    Filed: July 19, 2005
    Publication date: September 6, 2007
    Applicant: NSK, LTD.
    Inventors: Kenichi Iso, Yujiro Toda, Yoichi Imamura
  • Publication number: 20070205734
    Abstract: A torque detection portion includes a first arm having a detection coil L1 and a resistor R1, and a second arm having a detection coil L2 and a resistor R2. When a test mode is set, a reference voltage Vref having an abnormal value is outputted to a monitoring portion 13. An abnormal condition is intentionally caused in the monitoring portion 13. A main torque signal Vtm is compared with a sub torque signal Vts in the monitoring portion 13. When the reference voltage Vref set in the monitoring portion 13 has the abnormal value, a sub torque signal Vts having a level of 0 (Vts=0) is forcibly outputted inanormal condition. Then the signal Vtm is equal to the signal Vts, the monitoring portion 13 determines that a shortcircuit occurs between a main torque signal line and a sub torque signal line.
    Type: Application
    Filed: February 22, 2007
    Publication date: September 6, 2007
    Applicant: NSK LTD.
    Inventors: Yasushi Miyazawa, Keiji Sato
  • Patent number: 7265080
    Abstract: The rolling bearing of the invention to be incorporated in the compressor for fuel cell system comprises a fluorine-based grease containing a fluororesin and a fluorine-based oil, a urea grease containing a urea compound and a synthetic oil or a lithium complex grease containing a lithium complex and a synthetic oil encapsulated therein. In this arrangement, the grease deterioration of the rolling bearing incorporated in the compressor for force-feeding various fluids between machines can be prevented, making it possible to provide a fuel cell system which can maintain stable operation over an extended period of time.
    Type: Grant
    Filed: May 20, 2003
    Date of Patent: September 4, 2007
    Assignee: NSK Ltd.
    Inventors: Kenichi Iso, Hirotoshi Miyajima, Katsuaki Denpou, Yujiro Toda, Masahiko Yamazaki, Michiharu Naka, Yasunobu Fujita
  • Patent number: 7264249
    Abstract: A hub unit including a hub and a flange integrally formed with the hub, and a seal including a core metal and an elastic body integrally molded with the core metal. The elastic body includes one or more lips in sliding contact with one or both of the hub and the flange. The elastic body includes a molded rubber, wherein the molded rubber contains, as a raw rubber, acrylonitrile/butadiene rubber having an acrylonitrile monomer content of from 26 to 36% by weight. In a first embodiment, the hub unit includes a hub adapted for receiving a shaft and a flange integrally formed with the hub, and the seal is attached to an outer circumference of the hub unit. In a second embodiment, the hub unit includes an inner ring having a raceway surface for receiving rolling elements and an outer ring. The seal seals the space between the inner ring and the outer ring. Furthermore, the seal includes a radial lip in sliding contact with an outer circumferential surface of the hub.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: September 4, 2007
    Assignee: NSK, Ltd.
    Inventors: Keisuke Yokoyama, Takahiko Uchiyama, Toshikazu Yabe, Toshimi Takajo
  • Patent number: 7265509
    Abstract: The present invention provides an excellent electric power steering apparatus in which torque ripple caused by a quantization error of a current control system generated in case of slow steering state and steering holding state, namely, vibration and noise on a steering wheel can be suppressed. A current controller in which a steady state gain of feedback control is a finite value is used so as to be capable of suppressing the vibration and noise. Further, according to the present invention, a smoothing filter is included in a current control system so that the quantization error is smoothed so that the torque ripple is suppressed.
    Type: Grant
    Filed: July 15, 2005
    Date of Patent: September 4, 2007
    Assignee: NSK, Ltd.
    Inventors: Shuji Endo, Yuho Aoki, Kenji Mori, Toru Sakaguchi, Sakae Nejo, Hideaki Okazaki, Lilit Kovudhikulrungsri
  • Publication number: 20070194666
    Abstract: To reduce the vibration appearing at a motor for an electric power steering apparatus and further reduce noise caused by the vibration generated from the motor for an electric power steering apparatus. The motor for an electric power steering apparatus includes a rotor, a stator and a yoke 12 which houses the rotor and the stator therein and pivotally supports the rotation shaft 14 of the rotor so as to rotate freely. At least one annular band 26 is attached via an elastic member 28 to the outer peripheral surface of the yoke 12.
    Type: Application
    Filed: February 6, 2007
    Publication date: August 23, 2007
    Applicant: NSK LTD.
    Inventors: Tomohisa Hirakawa, Suguru Nagano
  • Patent number: 7258615
    Abstract: An elastic shaft joint is constituted of a joint member, a shaft member being fitted in a shaft of the joint member, and an elastic bush having a cylindrical inner sleeve fitted and fixed on the joint member, a cylindrical elastic member fixed on an outside surface of the inner sleeve, and a cylindrical outer sleeve fixed on an outside surface of the elastic member, for elastic torque transmission between the joint member and the shaft member, wherein the outer sleeve is fixed on the shaft member.
    Type: Grant
    Filed: January 17, 2006
    Date of Patent: August 21, 2007
    Assignee: NSK Ltd.
    Inventors: Kiyoshi Sadakata, Hiromichi Komori
  • Patent number: 7255369
    Abstract: An impact energy absorbing member in which a plurality of impact absorbing plates are arranged with predetermined intervals along a direction in which a collapse stroke progresses is provided on either one of a vehicle side bracket or a column side bracket slidably fitted to the vehicle side bracket. On the other bracket, there is provided a breaking member for sequentially breaking said plurality of impact absorbing plates as the collapse stroke progresses. With this structure, the impact energy absorbing member is sequentially broken by the breaking member as the collapse stroke progresses upon secondary collision, so that impact energy is absorbed.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: August 14, 2007
    Assignee: NSK Ltd.
    Inventor: Takeshi Matsumiya
  • Patent number: 7255479
    Abstract: In a linear guide apparatus including an axially extending guide rail, a slider engaged with the guide rail, and a plurality of rolling elements loaded into the slider, the linear guide apparatus further includes a sealing device fixed to the slider in slidable contact with the guide rail for sealing a clearance existing between the guide rail and the slider, in which the sealing device includes: a lubricant-containing polymer member formed of a synthetic resin containing a lubricant, and having a contact portion contacting with the guide rail to surround the guide rail, both wing portions, a connecting portion connecting the wing portions to be C-shaped substantially, and a pair of first recesses formed in the respective wing portions for fixing the lubricant-containing polymer member to the slider; a first plate member fitted to the lubricant-containing polymer member opposed to the slider; and a pair of first cylindrical members inserted to the respective first recesses.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: August 14, 2007
    Assignee: NSK Ltd.
    Inventors: Toru Tsukada, Yutaka Igarashi, Soichiro Kato, Toshikazu Yabe, Fumio Ueki
  • Publication number: 20070182733
    Abstract: It is possible to match a parts model with a two-dimensional drawing. A parts model has shape changing elements whose shapes are changed before and after assembling and other common elements. Three-dimensional shape data on the shapes of the shape changing elements before assembling and their shapes after assembling and the shapes of the common elements are stored as three-dimensional shape data on the parts model in database 12. A calculation unit 14 sets a restriction condition to become a single part between the shapes of the shape changing elements before assembling and the shapes of the common elements for the three-dimensional shape data stored in the database 12 and sets a restriction condition to become a single part between the shapes of the shape changing elements after assembling and the shapes of the common elements, so that three-dimensional shape data is spread into the two-dimensional drawing according to the restriction condition and displayed on the screen of the display unit 16.
    Type: Application
    Filed: June 21, 2005
    Publication date: August 9, 2007
    Applicant: NSK LTD.
    Inventor: Kenji Imanishi
  • Publication number: 20070180945
    Abstract: When a column 4 reaches a tilting ascent end, the lower end 732 of a nut 73 abuts on the buffering segment 83 of a buffer 82. Thus, while the buffering segment 83 of the buffer 82 is elastically deformed, the nut 73 stops with no impact. Accordingly, the inertia when the nut 73 stops is restrained and the tightening torque of the nut 73 when the nut 73 stops is also restrained. For this reason, when an electric motor 61 is rotationally driven in a reverse direction, a feeding screw shaft 71 rotates in the reverse direction with the normal rotation torque of the electric motor 61. Thus, the nut 73 is caused to ascend in the axial direction along the screw segment of the feeding screw shaft 71 so that the column 4 can be tiltingly moved downward.
    Type: Application
    Filed: February 8, 2007
    Publication date: August 9, 2007
    Applicant: NSK LTD.
    Inventors: Masaki Tomaru, Yuuichi Tomaru, Kouhei Yonezawa, Naoki Sawada
  • Patent number: 7254551
    Abstract: The machine element selection support system comprises a database apparatus and a selection support server, while the selection support server is connected to a network. A customer, who wishes to select a machine element, gains access to the selection support server using a customer terminal.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: August 7, 2007
    Assignee: NSK Ltd.
    Inventors: Hiroyuki Nakano, Yasushi Morita
  • Patent number: 7249891
    Abstract: The present invention relates to a bearing apparatus with a sensor and a rolling bearing with a sensor used to movers such as automobiles or railway carriers, facility machines of equipment, or machine tools. One of the embodiments comprises a sensor detecting conditions of the rolling bearing, a ring-shaped sensor cover housing the sensor therein and secured to a stationary-side bearing ring, and a ring shaped presser member secured to a bearing housing provided outside in a radius direction of the sensor cover, or secured to a shaft, and an opening portion is provided at a decided portion of the sensor cover, and projections standing toward a side of the presser member are furnished in the circumference of the opening portion, the presser member is defined with cutouts for inserting the projections, and the cutouts are arranged with the projections.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: July 31, 2007
    Assignee: NSK Ltd.
    Inventors: Mamoru Aoki, Ikunori Sakatani, Masamitsu Watanabe
  • Patent number: 7249892
    Abstract: When a minimum thickness of a part where an outer ring raceway is provided on a middle portion in the axial direction of an outer ring is h, and a diameter of each rolling element is Da, the relationship 0.4 Da?h 0.8 Da is satisfied. As a result, even when the outer ring 4a is fixed in a transmission case of low-rigidity, elastic deformation of the outer ring can be prevented without needlessly increasing the thickness h of the outer ring. When an outer diameter of an outer ring is D, a width of this outer ring in the axial direction is W, a minimum thickness of a part where the outer ring raceway is provided on a middle portion in the axial direction of the outer ring is h, and a diameter of each ball is Da, the respective dimensions are controlled such that a value K calculated by {(h1.5·W)/(Da1.1·.D0.5)} satisfies the relationship 1.20?K?2.00.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: July 31, 2007
    Assignee: NSK Ltd.
    Inventors: Hiromichi Takemura, Yoshiaki Sakajiri
  • Patent number: 7246946
    Abstract: Rotation torque of the hub rotating together with the road wheel is reduced to improve the driving performance of the vehicle such as acceleration performance, fuel consumption. The opening at both ends of the space where balls 14, 14 are provided is covered by seal rings 16c, 16d each having two or three seal lips. The whole rotation torque of the both seal rings 16c, 16d based on the friction between the seal lips and the mating surface is reglated between 0.06 N·m and 0.4 N·m.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: July 24, 2007
    Assignee: NSK Ltd.
    Inventor: Junshi Sakamoto
  • Patent number: 7243563
    Abstract: A friction applying apparatus and a linear guide apparatus having the same, according to the present invention can uniformly contact allover contacting faces of sliding members to the contacted members so as to reduce abrasion in the sliding members and the contacted members, and may maintain appropriate frictional force and precision. In the friction applying apparatus forcing the sliding members moving along guide rails for generating friction, the sliding member is made of a material having elastic modulus being 5000 MPa or less and Vickers hardness being 400 or more.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: July 17, 2007
    Assignee: NSK, Ltd.
    Inventors: Soichiro Kato, Masaru Akiyama
  • Patent number: RE39748
    Abstract: A sealed actuator includes a motor stator having rotation-drive magnetic poles; a motor rotor arranged so as to confront magnetic pole surfaces of the motor stator while interposing a small distance therebetween and rotatably supported through roller bearings; and displacement detecting means for measuring displacement of the motor rotor. A partition wall made of a nonmagnetic metal is disposed in a clearance between the motor stator and the motor rotor, so that the inner space where the motor stator is disposed is hermetically covered. The bearings are disposed at both sides of the partition wall in the axial direction so that the load applied to the bearings are directly received by a housing. At least a part of the partition wall is reinforced by reinforcing members and a mold agent is charged into the space on the motor stator side.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: July 31, 2007
    Assignee: NSK, Ltd.
    Inventors: Hayao Watanabe, Atsushi Horikoshi