Patents Assigned to NSK
  • Publication number: 20230400065
    Abstract: A producing method of a bearing unit includes: a step of measuring torque of a first bearing unit under each of a plurality of load conditions during production of the first bearing unit; a step of determining a target value of each of a plurality of production parameters based on of a load-torque relationship obtained from measurement results of the torque; and a step of producing a second bearing unit on the basis of the target value of each of the plurality of production parameters.
    Type: Application
    Filed: August 16, 2021
    Publication date: December 14, 2023
    Applicant: NSK LTD.
    Inventor: Nobuyuki HAGIWARA
  • Publication number: 20230392653
    Abstract: A distance (D1) between a rotation center (O) of an input member (3) and a contact portion (Pin) between an input side engaging portion (9) and an input side engaged portion (17) in a second direction is set to be shorter than a distance (D2) between a rotation center (O) of an output member (4) and a contact portion (Pout) between an output side engaging portion (12) and an output side engaged portion (14) in the second direction in a state in which a pair of pressing surfaces (13) is pressed against a pressed surface (6) in accordance with a rotation of the output member (4) in a predetermined direction and the input side engaging portion (9) engages with the input side engaged portion (17) in accordance with a rotation of the input member (3) in a direction opposite to the predetermined direction.
    Type: Application
    Filed: October 28, 2022
    Publication date: December 7, 2023
    Applicant: NSK Ltd.
    Inventors: Nagao DOHI, Shohei KANEKO
  • Patent number: 11835141
    Abstract: To provide a dust cover capable of maintaining a state in which a first flexible part and a second flexible part of a bellows are fitted onto a mounting member. A dust cover includes a bushing, a bellows, and a mounting member. The mounting member has a main body and a flange part.
    Type: Grant
    Filed: June 18, 2020
    Date of Patent: December 5, 2023
    Assignee: NSK LTD.
    Inventor: Seiichi Moriyama
  • Publication number: 20230383826
    Abstract: A ball screw device that is capable of transmitting an axial load between the screw portion and the holding member without shortening the life of the ball screw device is provided. The stopper 5 is externally fitted to the fitting shaft portion 10 of the screw shaft 2 having an outer diameter smaller than that of the screw portion 9, which is provided adjacent to one side in the axial direction of the screw portion 9 provided with the shaft-side ball thread groove 12 on the outer-circumferential surface, so as not to be able to rotate relative to each other. The driving member 6 which is a holding member is arranged adjacent to the one side in the axial direction of the stopper 5 such that the stopper 5 is held in the axial direction between the driving member 6 and the screw portion 9. An axial load is transmitted between the driving member 6 and the screw portion 9 without applying a moment to the stopper 5.
    Type: Application
    Filed: April 11, 2022
    Publication date: November 30, 2023
    Applicant: NSK LTD.
    Inventor: Ryo SEGAWA
  • Publication number: 20230384252
    Abstract: A condition diagnosis method includes: a measurement step of measuring relative dielectric constant of a lubricant by applying a voltage to the lubricant while changing a frequency from an AC power source; a derivation step of deriving parameters indicating electrical properties of the lubricant by applying the relative dielectric constant measured in the measurement step to a theoretical formula; and a diagnosis step of diagnosing a condition of the lubricant using the parameters.
    Type: Application
    Filed: September 24, 2021
    Publication date: November 30, 2023
    Applicant: NSK LTD.
    Inventors: Shunsuke IWASE, Taisuke MARUYAMA
  • Patent number: 11828698
    Abstract: Provided are a method for assessing hydrogen environment severity of a rolling device during operation and a method for predicting likelihood that white structure damage occurs to the rolling device as a result of operation. A hydrogen environment severity assessment method is a method for assessing, among operating conditions of a rolling device including two rolling members coming into rolling contact with each other and having at least one of the two rolling members being a steel rolling member, hydrogen environment severity, the hydrogen environment severity being an index representing magnitude of influence exerted by hydrogen.
    Type: Grant
    Filed: October 31, 2019
    Date of Patent: November 28, 2023
    Assignee: NSK Ltd.
    Inventors: Hiroki Yamada, Atsushi Imai, Hideyuki Uyama
  • Patent number: 11827291
    Abstract: A motor control device includes a third harmonic calculation unit configured to calculate a first third harmonic on a basis of an average value between a voltage command value of a maximum phase with a maximum duty ratio and a voltage command value of a minimum phase with a minimum duty ratio among three-phase voltage command values; an amplitude calculation unit configured to calculate an amplitude of the three-phase voltage command values; a third harmonic conversion unit configured to convert the first third harmonic into a second third harmonic on a basis of the first third harmonic and the amplitude; a correction unit configured to correct the three-phase voltage command values by subtracting the second third harmonic from the three-phase voltage command values.
    Type: Grant
    Filed: October 2, 2020
    Date of Patent: November 28, 2023
    Assignee: NSK LTD.
    Inventors: Yasutoshi Miki, Masahiro Maeda
  • Publication number: 20230375081
    Abstract: The ball screw device has a nut having a guide concave groove on the outer-circumferential surface capable of engaging with a rotation restraining member in the circumferential direction, a housing provided with an insertion hole having a retaining concave groove on the inner-circumferential surface capable of engaging with the rotation restraining member in the circumferential direction, the rotation restraining member configured by a shaft-shaped member extending in the axial direction, the rotation restraining member having an outside portion in the radial direction arranged inside the retaining concave groove and an inside portion in the radial direction arranged inside the guide concave groove, so as to be able to slide in the axial direction.
    Type: Application
    Filed: June 16, 2022
    Publication date: November 23, 2023
    Applicant: NSK LTD.
    Inventor: Ryo SEGAWA
  • Patent number: 11821810
    Abstract: A magnetic sensor arranged close to a component of a rolling machine element measures magnetic flux density in the axial direction and/or radial direction of the component, then the amount of change in magnetic flux density is calculated based on a reference magnetic flux density corresponding to the magnetic flux density before the start of use of the component, and the progression of fatigue of the rolling machine element is determined from the amount of change.
    Type: Grant
    Filed: February 5, 2020
    Date of Patent: November 21, 2023
    Assignee: NSK LTD.
    Inventors: Daisuke Kobayashi, Koichiro Ono
  • Patent number: 11821463
    Abstract: Provided are an oil receiver (20) having an annular recess portion (52) which faces an entire circumference of an outer circumferential edge of a concave spherical portion (36), and a guide member (21) which guides lubricating oil, which has flowed out from a spherical engagement portion between a convex spherical portion (24) and a concave spherical portion (36), toward an annular recess portion (52).
    Type: Grant
    Filed: February 25, 2019
    Date of Patent: November 21, 2023
    Assignee: NSK LTD.
    Inventors: Tetsurou Maruno, Satoshi Sugai, Hiroaki Yamazaki, Nobuyuki Hagiwara
  • Publication number: 20230366781
    Abstract: A detection method for detecting a state of a bearing device including an outer member, an inner member, and a plurality of rolling elements, the detection method including: applying an alternating current voltage to an electric circuit including the outer member, the rolling element, and the inner member while a predetermined load is applied to the bearing device; measuring an impedance and a phase angle of the electric circuit applied with the alternating current voltage; and deriving an oil film thickness and a metal contact ratio between the inner member and the plurality of rolling elements or between the inner member and at least one of the plurality of rolling elements based on the impedance and the phase angle.
    Type: Application
    Filed: May 31, 2021
    Publication date: November 16, 2023
    Applicant: NSK LTD.
    Inventors: Taisuke MARUYAMA, Suguru SUGAWARA, Masayuki MAEDA
  • Publication number: 20230366436
    Abstract: An assembly of a gear and rotating shaft, comprising: a gear having teeth on an outer peripheral surface thereof, and a center hole penetrating in an axial direction through a center portion thereof; and a rotating shaft including a serrated shaft portion having a male serration portion on an outer peripheral surface thereof and press-fitted into the center hole, and a guide shaft portion provided adjacent to one side in the axial direction of the serrated shaft portion and having an outer diameter capable of being internally fitted in the center hole with a clearance fit.
    Type: Application
    Filed: March 11, 2022
    Publication date: November 16, 2023
    Applicant: NSK LTD.
    Inventor: Seiji ICHIDA
  • Publication number: 20230366451
    Abstract: A two-speed transmission includes: an input member; an output member; a rotating member; a first engaging device switching engagement between first and second friction plates to switch the input member and the rotating member to an integrally rotating state or a relatively rotating state; a second engaging device switching the rotating member to a rotatable or non-rotatable state; an elastic biasing means applying a force pressing the first and second friction plates; a pressing device releasing the pressing force; a first bearing between the elastic biasing means and the pressing device; a second bearing between the rotating member and the pressing device or the fixed portion; and a planetary speed reduction mechanism having a sun element connected to the input member or the rotating member, a carrier connected to one of the input member or the rotating member and the output member, and a ring element connected to the other.
    Type: Application
    Filed: August 27, 2021
    Publication date: November 16, 2023
    Applicant: NSK Ltd.
    Inventors: Akihiro YAMAMOTO, Hirotaka KISHIDA
  • Publication number: 20230366750
    Abstract: Provided is a temperature derivation method for deriving an oil film temperature of a lubricant in a device, the temperature derivation method including a measurement step of measuring a dielectric constant of the lubricant by applying an alternating voltage while changing a frequency to an electric circuit configured by the device, a derivation step of 5 applying the dielectric constant measured in the measurement step to a theoretical formula to derive a relaxation time of the lubricant, and a calculation step of calculating the oil film temperature by using the relaxation time.
    Type: Application
    Filed: September 24, 2021
    Publication date: November 16, 2023
    Applicant: NSK LTD.
    Inventors: Shunsuke IWASE, Taisuke MARUYAMA
  • Patent number: 11817934
    Abstract: A wireless communication system includes a wireless sensor provided inside a metal housing; a receiver provided outside the metal housing to receive radio waves from the wireless sensor; and a passive repeater provided between the inside and the outside of the metal housing. The passive repeater includes a receiving antenna provided inside the metal housing and a transmitting antenna provided outside the metal housing. The receiving antenna of the passive repeater and the transmitting antenna of the passive repeater are electrically connected through a hole formed in the metal housing.
    Type: Grant
    Filed: September 29, 2021
    Date of Patent: November 14, 2023
    Assignee: NSK LTD.
    Inventors: Keisuke Manabe, Toshihiko Okamura, Tomoyuki Yanagisawa
  • Patent number: 11814116
    Abstract: An assist mechanism includes: an electric motor; a shaft-shaped member in which a worm engaged with a worm wheel is formed; and a coupling that couples an output shaft of the electric motor and the shaft-shaped member to each other. The smallest rotation order among rotation orders of the electric motor and a rotation order of the worm are prime to each other. The smallest rotation order among the rotation orders of the electric motor and a rotation order of the coupling are prime to each other. The rotation order of the worm and the rotation order of the coupling are prime to each other. The rotation order of the worm is 3. The rotation order of the coupling is 5 or 7.
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: November 14, 2023
    Assignee: NSK LTD.
    Inventor: Yasushi Honda
  • Publication number: 20230358277
    Abstract: A groove curvature radius ratio Ri of the inner ring raceway groove to a ball diameter is 54% to 58%, a groove curvature radius ratio Ro of an outer ring raceway groove of an outer ring to the ball diameter is 51% to 58%, and Ri?Ro?0 points. At least an inner ring raceway groove of an inner ring has a maximum surface pressure of 4.7 GPa to 6.0 GPa when a sum of permanent deformation amounts of the ball and the inner ring raceway groove at a center of a contact portion between a ball of an angular ball bearing and the inner ring raceway groove is 1/10,000 of the ball diameter. Accordingly, it is possible to provide the angular ball bearing that can reduce the heat generation amount, and that can reduce the damage caused by the external impact load in the stationary state.
    Type: Application
    Filed: September 15, 2021
    Publication date: November 9, 2023
    Applicant: NSK LTD.
    Inventors: Shuji SOGA, Yoshiaki KATSUNO
  • Publication number: 20230358278
    Abstract: Provided is a rolling bearing using a retainer, particularly a highly reliable retainer in which dimensional stability required for a retainer of an outer ring guide type, ductility required for a crown-type retainer, improvement in adhesion of grease with a poly-?-olefin oil or the like as a base oil, and deformation prevention at a high speed can be achieved. The rolling bearing includes at least an inner ring 1, an outer ring 3, a synthetic resin retainer 9, and a rolling element 7, in which the synthetic resin retainer 9 is formed of a polyamide resin composition including polyamide 410 and a reinforcing fiber material with a content of 0% by weight to 40% by weight.
    Type: Application
    Filed: September 27, 2021
    Publication date: November 9, 2023
    Applicant: NSK LTD.
    Inventors: Toshikazu YABE, Tomoaki MATSUMOTO, AZUMA ITO, Keisuke YOKOYAMA, Nariaki AIHARA, Shintaro HONDA
  • Patent number: 11808328
    Abstract: To provide a nut that can suppress increase in the number of components. The nut according to the present disclosure includes a nut main body and a circulation component. The nut main body includes a housing part having a bow shape when viewed from an axial direction, a seat surface, a through hole, and a pair of side surfaces. The circulation component includes a circulation component main body, two arm parts extending toward both sides in a seat surface direction from the circulation component main body, ribs projecting from the respective two arm parts, and caulking parts obtained by caulking the ribs. Recessed parts that the caulking parts enter are disposed on the pair of side surfaces. A ball passage is disposed in the circulation component main body.
    Type: Grant
    Filed: October 13, 2022
    Date of Patent: November 7, 2023
    Assignee: NSK LTD.
    Inventors: Yasuaki Abe, Shuhei Yumiba, Yasumi Watanabe
  • Patent number: RE49737
    Abstract: A ball bearing includes an inner ring having a raceway surface, an outer ring having a raceway surface, a plurality of rolling elements rollably disposed between the raceway surface of the inner ring and the raceway surfaces of the outer ring, and a resin cage configured to retain the plurality of rolling elements between the inner ring and the outer ring. The cage is a crown type cage having an annular base portion and a plurality of pockets formed in an axial end face of the annular base portion, in which the pockets retain the rolling elements. An axial distance between an axial position of a center of gravity of the cage and a curvature center of a spherical or cylindrical inner surface of each of the pockets is 0.6 or more times a radius of curvature of the inner surface. A hybrid vehicle transmission has this ball bearing.
    Type: Grant
    Filed: October 4, 2019
    Date of Patent: November 28, 2023
    Assignee: NSK LTD.
    Inventors: Takeshi Maejima, Takanori Tanaka, Youichi Matsumoto