Patents Assigned to JTEKT
  • Patent number: 11033974
    Abstract: A gear machining apparatus and a gear machining method are provided. The gear machining apparatus performs cutting work for a workpiece and generates a gear by performing a feed operation of a gear cutter relative to the workpiece along a direction of an axis of the workpiece while synchronously rotating the gear cutter and the workpiece in a state in which an axis of the gear cutter is inclined with respect to a line parallel to the axis of the workpiece. The gear machining apparatus sets a correction angle to a first angle when cutting work for a second tooth flank is started after cutting work for a first tooth flank is finished, and moves the gear cutter from a first finish position to a second start position while rotating the workpiece and the gear cutter.
    Type: Grant
    Filed: September 16, 2019
    Date of Patent: June 15, 2021
    Assignee: JTEKT Corporation
    Inventors: Hiroyuki Nakano, Hisashi Otani, Shuntaro Takasu
  • Patent number: 11033953
    Abstract: A method is provided for manufacturing an outer ring of a constant velocity joint including an outer ring, an inner rotational member, a torque-transmitting rolling element, and a defining member. The outer ring includes: a first inner peripheral surface to which the defining member is attached; a second inner peripheral surface; and protrusions protruding radially inward of the first inner surface and the second inner peripheral surface so as to restrict axial movement of the inner rotational member and the rolling element. The manufacturing method includes: a plastic working step involving providing a base member; and a bottom removing step involving partially removing a bottom of the base member so as to form a through hole. The plastic working step further involves providing the second inner peripheral surface. The bottom removing step further involves providing the protrusions.
    Type: Grant
    Filed: May 3, 2017
    Date of Patent: June 15, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Isashi Kashiwagi, Takashi Okazaki
  • Publication number: 20210172890
    Abstract: A fatigue estimating method of estimating a degree of fatigue of a metallic material includes: estimating a fatigue portion in which fatigue appears in a section of the metallic material, obtaining a crystal grain size of each of a plurality of crystal grains in a measurement area set in the fatigue portion, based on crystal misorientation in the measurement area, obtaining a fatigue portion existence rate indicating an existence proportion of particular crystal grains of which the crystal grain size is within a predetermined numeral range, in the measurement area, and obtaining an estimated degree of fatigue of the metallic material, based on at least one of the fatigue portion existence rate, and a change rate of the fatigue portion existence rate before and after fatigue of the metallic material.
    Type: Application
    Filed: November 18, 2020
    Publication date: June 10, 2021
    Applicant: JTEKT CORPORATION
    Inventor: Yousuke NAGANO
  • Publication number: 20210172477
    Abstract: A cage includes: a first holding portion in which a plurality of radial rollers is held; a second holding portion in which a plurality of thrust rollers is held; and a connecting portion via which the first holding portion is connected to the second holding portion. The first holding portion, the second holding portion, and the connecting portion are molded integrally by a resin member.
    Type: Application
    Filed: December 2, 2020
    Publication date: June 10, 2021
    Applicant: JTEKT CORPORATION
    Inventor: Kotaro YAMASHITA
  • Publication number: 20210172476
    Abstract: A radial roller bearing cage includes a pair of annular bodies; and a plurality of bars by which the annular bodies are axially connected to each other. The annular bodies and the bars are integrally formed by resin molding. A plurality of pockets separated from each other by the bars is provided between the annular bodies. A projection projecting radially inwardly is provided in at least one of parts of at least one of the annular bodies, the parts axially facing the pockets, respectively.
    Type: Application
    Filed: November 30, 2020
    Publication date: June 10, 2021
    Applicant: JTEKT CORPORATION
    Inventor: Kotaro YAMASHITA
  • Patent number: 11028914
    Abstract: A vehicle differential device includes a plurality of pinion gear sets. Each of the pinion gear sets includes a first pinion gear configured to mesh with a first outer helical gear and a plurality of second pinion gears configured to mesh with a second outer helical gear. The first pinion gear integrally includes an axially one end side gear portion configured to mesh with the first outer helical gear and an axially other end side gear portion configured to mesh with the second pinion gears. The second pinion gears are configured to mesh with the second outer helical gear at positions separated from each other in a circumferential direction of the second outer helical gear, and the axially other end side gear portion of the first pinion gear is configured to mesh with the second pinion gears at positions radially outward of the second outer helical gear.
    Type: Grant
    Filed: November 21, 2019
    Date of Patent: June 8, 2021
    Assignee: JTEKT Corporation
    Inventors: He Jin, Tomoki Yoshihama, Kenji Asami, Songjie Li
  • Patent number: 11027766
    Abstract: A steering apparatus includes: a column shaft; a column tube supporting the column shaft; a housing movably supporting the column tube; a fastener configured to fix the position of the column tube by pressing on radial ends of the housing; a first impact absorber configured to generate a first dynamic friction force with the column tube; and a second impact absorber configured to generate a second dynamic friction force with the housing during a secondary collision by being moved by the first impact absorber. The first impact absorber is structured such that a distal static friction coefficient in a distal region located further from a squeezing portion of the fastener is less than a proximal static friction coefficient in a proximal region closer to the squeezing portion.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: June 8, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Satoshi Abe, Yoshitaka Miyanaga, Norihito Tanaka, Satoshi Matoba
  • Patent number: 11027769
    Abstract: A steering system includes a rack shaft, a housing, an electric motor, a control device, and a speed reduction mechanism that applies a moving force in the axial direction to the rack shaft with the speed of rotation of the electric motor reduced. The housing has a rack shaft housing portion and a speed reduction mechanism housing portion. The electric motor has: a motor case fixed to the housing; a plurality of stator cores disposed annularly in the motor case; coil windings wound around the plurality of stator cores; and a rotor. The motor case is formed with a water introduction hole that introduces water that has entered the speed reduction mechanism housing portion into the motor case. The control device has a detector that detects entry of water into the motor case.
    Type: Grant
    Filed: November 30, 2018
    Date of Patent: June 8, 2021
    Assignee: JTEKT CORPORATION
    Inventor: Yuto Sato
  • Patent number: 11027772
    Abstract: A motor controller is configured to control a motor including a plurality of winding groups. The motor controller includes a plurality of processors. Each of the processors is configured to independently control supply of driving electric power to each of the winding groups. When an abnormality occurs in which a torque to be generated in one of the winding groups is smaller than an individual rated torque and when a target overall torque is larger than a total of the individual rated torque for the winding group in which the abnormality does not occur, the processor, controlling supply of driving electric power to the winding group in which the abnormality does not occur, out of the plurality of processors controls supply of the driving electric power such that the winding group generate a torque larger than the individual rated torque.
    Type: Grant
    Filed: December 19, 2019
    Date of Patent: June 8, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Hiroshi Kawamura, Yuji Fujita
  • Publication number: 20210162859
    Abstract: A driving force transmission device includes an input rotation member and output rotation member, a multiple-disc clutch, a pressing mechanism, and a control device that includes a current supply circuit. The control device is configured to compute a torque command value based on a state of a vehicle, the torque command value being a driving force that needs to be transmitted by the multiple-disc clutch, to compute a current command value, to correct the current command value, and to control the current supply circuit such that an electric current depending on the current command value is supplied to the pressing mechanism. The control device is configured to perform the correction so as to increase or decrease the current command value by a correction amount depending on a change rate of the torque command value.
    Type: Application
    Filed: November 23, 2020
    Publication date: June 3, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Ichiro ODA, Go NAGAYAMA, Tomonori ONO, Takashi KOUZAI
  • Publication number: 20210164869
    Abstract: A method for a power steering system for empirically determining at least one property of the system, power steering system including at least one steering wheel, a steering mechanism provided with a rack, and at least one assist motor, method having, outside a steering phase during which the power steering system is assigned to the driving of a vehicle in order to cause vehicle to follow a trajectory which is determined as a function of the situation of vehicle with respect to its environment, a step (a) of automatically activating the assist motor, during which step a computer is used to automatically generate and apply to the assist motor; at least one indicator parameter which is specific to the response by the powersteering system to the automatic activation of the assist motor and which is characteristic of the desired property.
    Type: Application
    Filed: December 3, 2018
    Publication date: June 3, 2021
    Applicant: JTEKT EUROPE
    Inventors: Matthieu LOUSSAUT, Christophe RAVIER
  • Publication number: 20210164527
    Abstract: A driving force transmission device includes an input rotation member, an output rotation member, a multiple-disc clutch, a pressing mechanism, and a control device including a current supply circuit. The control device is configured to compute a torque command value, to compute a current command value, to correct the current command value, and to control the current supply circuit such that an electric current depending on the current command value is supplied to the pressing mechanism. The control device is configure to correct the current command value by a correction amount in a constant-torque state after the torque command value changes, the constant-torque state being a state where a change rate of the torque command value is in a predetermined range, the correction amount depending on a duration of the constant-torque state.
    Type: Application
    Filed: November 19, 2020
    Publication date: June 3, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Ichiro ODA, Go NAGAYAMA, Tomonori ONO, Takashi KOUZAI
  • Patent number: 11022172
    Abstract: A rolling bearing device includes a rotary shaft; a housing; a pair of rolling bearings; an outer ring spacer; an elastic member provided in a bottom side of the housing, the bottom side of the housing being a second axial side of the housing, and the elastic member being configured to urge the rolling bearings, the outer ring spacer, and the rotary shaft toward a first axial side; and a retaining ring that is fitted into a circumferential groove provided on an inner periphery in the first axial side of the housing, the retaining ring being in axial contact with the outer ring of the rolling bearing located on the first axial side, and the retaining ring including at least three arc members arranged in a circumferential direction.
    Type: Grant
    Filed: March 2, 2020
    Date of Patent: June 1, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Yui Tanaka, Kazuhiro Kimura, Masaaki Ohtsuki
  • Patent number: 11022178
    Abstract: A sealing device includes a seal member and a slinger. The slinger has a slinger fixing part, a first radial part, a first axial part, a second radial part, and a second axial part facing a seal fixing part of the seal member in a radial direction across a first clearance. The seal member has a large-diameter part facing, in an axial direction, an end of the second axial part on the other side in an axial direction across a second clearance. An outer circumferential surface of the large-diameter part and an outer circumferential surface of the second axial part are included in a flow passage surface of a continuous outside flow passage that extends in a straight line along the axial direction. The first clearance and the second clearance communicate with each other, and the sealing device has a labyrinth clearance including the first clearance and the second clearance.
    Type: Grant
    Filed: February 26, 2020
    Date of Patent: June 1, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Takafumi Uemoto, Yuya Yamamoto, Takuya Toda, Suguru Nakajima
  • Patent number: 11022183
    Abstract: A method of manufacturing a universal joint includes: temporarily assembling a bearing, which supports a shaft portion of a joint spider such that the shaft portion is rotatable, with respect to a through-hole and the shaft portion by press-fitting the bearing to a first position in the through-hole of a yoke; and clinching, after the bearing is temporarily assembled, a portion of the yoke around the through-hole, and pressing the bearing deeper into the through-hole with a clinched portion formed by the clinching to press-fit the bearing to a second position located deeper than the first position in the through-hole.
    Type: Grant
    Filed: October 11, 2019
    Date of Patent: June 1, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Takeshi Koyama, Atsushi Tano
  • Publication number: 20210156428
    Abstract: A thrust roller bearing includes a plurality of radially arranged rollers, and a pair of annular washers having raceway surfaces on which the rollers roll, the raceway surfaces being arranged to face each other. The roller is made of high-carbon chromium bearing steel, and contains 1.1 mass % to 1.6 mass % of carbon and 0.1 mass % to 0.6 mass % of nitrogen in a range of 0.1 mm from a surface. A surface compressive residual stress is smaller than ?900 MPa, a surface roughness is 0.01 to 0.10 in terms of Rvk and 0.01 to 0.08 in terms of Rk, and a Vickers hardness of the surface is 860 to 980. At least one of the washers is made of carbon steel, and surface roughnesses of the raceway surfaces are 0.05 to 0.20 in terms of Rvk and 0.08 to 0.15 in terms of Rk.
    Type: Application
    Filed: November 18, 2020
    Publication date: May 27, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Keisuke KOKUBUN, Yoshihito NAKASHIMA, Taizou WAKAYAMA, Shingo WATANABE
  • Publication number: 20210155282
    Abstract: A steering control device includes an electronic control unit configured to calculate a d-axis current command value and a q-axis current command value for a motor having three phases configured to generate drive power applied to a shaft interlocked with turning wheels, to convert detected current values in the phases of the motor to a d-axis current value and a q-axis current value, and to perform feedback control. The electronic control unit is configured to perform field weakening control for setting the d-axis current command value to a negative value based on a rotation speed of the motor, to determine whether the motor is in a regenerative state, and to calculate the d-axis current command value according to the regenerative state of the motor when the electronic control unit determines that the motor is in the regenerative state.
    Type: Application
    Filed: November 18, 2020
    Publication date: May 27, 2021
    Applicant: JTEKT CORPORATION
    Inventor: Hisataka KATO
  • Publication number: 20210156420
    Abstract: A thrust roller bearing includes a plurality of radially arranged rollers, and a pair of annular washers having raceway surfaces on which the rollers roll. The raceway surfaces are arranged to face each other. The roller is made of high-carbon chromium bearing steel and has a surface roughness of 0.01 to 0.10 in terms of Rvk and 0.01 to 0.08 in terms of Rk. At least one of the washers is made of carbon steel, surface compressive residual stress of the raceway surface is ?1400 MPa to ?1000 MPa, and Vickers hardness of surface of the raceway surface is 850 to 900.
    Type: Application
    Filed: November 19, 2020
    Publication date: May 27, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Keisuke KOKUBUN, Yoshihito NAKASHIMA, Taizou WAKAYAMA, Shingo WATANABE
  • Patent number: 11014603
    Abstract: An ECU of a vehicle controls a motor on the vehicle. The ECU includes a microcomputer and a monitoring circuit. The monitoring circuit includes a rotation detection circuit that detects the number of rotations of the motor at a preset sampling interval, a control circuit including a logic circuit that controls an operation of the rotation detection circuit, and an inspection circuit that inspects of the control circuit. The microcomputer is started upon start of vehicle power supply and performs a specific process using the number of rotations of the motor detected by the rotation detection circuit. The inspection circuit performs the inspection of the control circuit in the monitoring circuit in a period in which the microcomputer is kept in a reset state after the vehicle power supply is turned on and which is within a sampling interval of the rotation detection circuit in the monitoring circuit.
    Type: Grant
    Filed: May 9, 2019
    Date of Patent: May 25, 2021
    Assignee: JTEKT CORPORATION
    Inventors: Kenichi Kozuka, Masato Oda
  • Publication number: 20210148447
    Abstract: A sliding member includes a first sliding member having a resin portion on its outer surface and a second sliding member having a metal portion that slides relative to the resin portion, wherein the resin portion of the first sliding member includes a resin containing a reinforcing filler and having a viscosity number VN of 180 ml/g or more, and the reinforcing filler has a hardness higher than that of the metal portion of the second sliding member. In the sliding component, preferably, the reinforcing filler has a Vickers hardness of 300 HV to 800 HV, and the metal portion has a Vickers hardness of 250 HV to 600 HV.
    Type: Application
    Filed: April 11, 2019
    Publication date: May 20, 2021
    Applicant: JTEKT CORPORATION
    Inventors: Yasuharu NAGAI, Setsuo NAGAI, Takeshi KUNISHIMA, Seiichi MACHIDA