Patents Assigned to JTEKT
  • Publication number: 20130137341
    Abstract: In a machining method of supporting a workpiece having a cylindrical machined portion such that the workpiece is rotatable and feeding a grinding wheel in a radial direction, a start diameter that is a diameter including a measurement start point on a surface of the machined portion is measured, and, after the measurement start point passes through a machining application portion, an end diameter that is a diameter including a measurement end point is measured. An actual grinding depth at the time when the measurement start point is machined is computed by the equation, U=|D0?D1|, a runout of the machined portion is computed from a relative difference in the actual grinding depth (U) between positions of the machined portion in a rotational direction, and infeed control of the grinding wheel is executed such that the runout is removed.
    Type: Application
    Filed: November 20, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT Corporation
    Inventor: JTEKT Corporation
  • Publication number: 20130134816
    Abstract: Non-holding portions of a holding ring are demagnetized by supplying a nonmagnetic element to the non-holding portions while melting the non-holding portions by the application of heat. Each non-holding portion is demagnetized such that, from the melting center toward each melting end portion thereof, the material of the non-holding portion moderately changes from a nonmagnetic material to a ferromagnetic material. The permeability moderately changes, and hence generation of cogging torque during rotation of a rotor is suppressed.
    Type: Application
    Filed: November 27, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT Corporation
    Inventor: JTEKT Corporation
  • Publication number: 20130138296
    Abstract: An acceleration sensor is attached to a rack housing. A FFT processing unit converts a signal output from the acceleration sensor, which is a time-domain signal, into a frequency-domain signal. An inverse input vibration component extraction unit extracts a signal, of which the frequency (f) falls within a predetermined range (fL?f?fH (fH>fL)) and of which the power density (?) falls within a predetermined range (?L????H (?H>?L)), from the frequency-domain signal obtained by the FFT processing unit. An IFFT processing unit converts the frequency-domain signal extracted by the inverse input vibration component extraction unit into a time-domain signal (estimated inverse input vibration).
    Type: Application
    Filed: November 16, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT CORPORATION
  • Publication number: 20130134827
    Abstract: Teeth coupling portions of a ring-shaped teeth member are demagnetized by supplying a nonmagnetic element to the teeth coupling portions while melting the teeth coupling portion by application of heat. Then, an inner peripheral portion of the ring-shaped teeth member is pressed radially outward. Therefore, it is possible to plastically deform the teeth coupling portions easily, so that the ring-shaped teeth member and a ring-shaped yoke member are easily fitted together. Accordingly, there is provided a method for manufacturing a stator for a motor, in which the amount of leakage flux is reduced and which has favorable magnetic characteristics.
    Type: Application
    Filed: November 27, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT Corporation
    Inventor: JTEKT Corporation
  • Publication number: 20130138300
    Abstract: In a vehicle steering system, when a sensor malfunction determination unit detects a malfunction of a rotation angle sensor, the sensor malfunction determination unit changes a control mode from a first control mode to a second control mode. In the second control mode, an actual rotor angle (mechanical angle) (?SM) of a steered system motor is computed on the basis of a second rotor angle (electric angle) (?SE2) estimated by a rotation angle estimation unit. Then, feedback control is executed such that the actual rotor angle (?SM) converges to a target rotor angle (?SM1*) that is obtained by superimposing a rotation maintaining command signal on a target rotor angle (?SM*) computed by a target rotor angle computation unit.
    Type: Application
    Filed: November 23, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT CORPORATION
  • Publication number: 20130138297
    Abstract: A damping control unit sets a damping torque command value that corresponds to a steering angular velocity when a direction of a detected steering torque is a turning direction, a magnitude of the detected steering torque is larger than or equal to a first threshold, a direction of the steering angular velocity is a returning direction and a magnitude of the steering angular velocity is higher than or equal to a second threshold. An addition unit adds the damping torque command value generated by the damping control unit to a basic assist torque command value set by a basic assist torque command value setting unit.
    Type: Application
    Filed: November 16, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT CORPORATION
  • Publication number: 20130134817
    Abstract: At least part of each bridge portion is heated and molten to form a keyhole, and a nonmagnetic element is disposed around the keyhole. Thus, even when the width of the bridge portion in the radial direction is increased, the bridge portion is demagnetized. Therefore, leakage flux in the bridge portion is reduced, and the output power of a motor is increased. Moreover, by increasing the width of the bridge portion in the radial direction, the strength of the bridge portion is increased, and breakage of the bridge portion due to a centrifugal force at high-speed rotation of a rotor is prevented.
    Type: Application
    Filed: November 27, 2012
    Publication date: May 30, 2013
    Applicant: JTEKT Corporation
    Inventor: JTEKT Corporation
  • Patent number: 8449269
    Abstract: An electric pump includes: a second housing and a first housing separated from each other in an axial direction; a stator portion that accommodates an annular coil portion; an outer rotor portion that is rotated based on a magnetic field generated by the coil portion, at a position on the inner side of the housings; and an inner rotor that is rotatably supported by a support shaft portion having an axis that is offset from that of the outer rotor portion, and that has an outer peripheral surface that is engaged with an inner peripheral surface of the outer rotor portion. The second housing is fitted onto the support shaft portion, to which the first housing has been fixed, from one side of the support shaft portion in the axial direction. As a result, the outer rotor portion and the stator portion are clamped between the first housing and the second housing from both sides in the axial direction.
    Type: Grant
    Filed: November 26, 2010
    Date of Patent: May 28, 2013
    Assignee: JTEKT Corporation
    Inventors: Motoyasu Yamamori, Noriyasu Hayashi, Daichi Kanda
  • Patent number: 8448742
    Abstract: An electric power steering system (1) includes a tubular sensor housing (34) which accommodates a torque sensor (20), a gear housing (32) which accommodates a speed reduction mechanism (24), and an upper bearing (40) and a lower bearing (41) which rotatably support a steering shaft (3) on opposite sides of the speed reduction mechanism (24). The gear housing (32) includes a tubular lower housing (37) supporting the lower bearing (41), and an upper housing (36). The upper housing (36) includes an inner tube (67), an outer tube (68), and an annular connection wall (69) connecting the inner tube (67) and the outer tube (68). The outer tube (68) is press-fitted in the lower housing (37). The inner tube (67) is press-fitted to an inner periphery (72) of a lower portion (71) of the sensor housing (34), whereby the inner tube (67) has a reduced diameter. As a result, an outer ring (44) of the upper bearing (40) is tightly fitted and supported in the inner tube (67).
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: May 28, 2013
    Assignee: JTEKT Corporation
    Inventors: Yoshikazu Kawada, Terukazu Nakajima, Toshiharu Mikami, Shingo Takayama
  • Publication number: 20130131927
    Abstract: A four-wheel steering control system includes; a torque sensor that detects a steering torque based on an operation of a steering member; a steering angle sensor that detects a steering angle; a steering assist control unit that calculates an assist force for steering front wheels based on the value detected by the torque sensor; and a steered system control unit that executes steered control on rear wheels based on the value detected by the steering angle sensor or the value detected by the torque sensor. When it is determined that there is a failure in a function of the steering assist control unit, the steered system control unit executes the steered control such that the rear wheels are steered only on the side where the steered angle of the rear wheels is opposite in phase from the steering angle of the steering member.
    Type: Application
    Filed: November 8, 2012
    Publication date: May 23, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT CORPORATION
  • Publication number: 20130129270
    Abstract: A rolling bearing apparatus capable of restraining the residence of air bubbles in the water-cooling jacket while curbing the running cost and the production cost is provided. A rolling bearing apparatus having a rolling bearing, and a housing which houses the rolling and in which a water-cooling jacket into which cooling water is introduced is formed. The water-cooling jacket is formed of: a recess portion that is indented radially inward from an outer peripheral surface of the housing and that has a bottom portion that extends along an outer periphery of the rolling bearing; and lid that, together with the recess portion, forms space into which the cooling water is introduced, by closing the recess portion. The bottom portion is formed of: a first inclined surface; and a second inclined surface.
    Type: Application
    Filed: April 2, 2010
    Publication date: May 23, 2013
    Applicant: JTEKT CORPORATION
    Inventor: Osamu Takahashi
  • Patent number: 8445077
    Abstract: A method of producing a coated member in which a base material surface is at least partially coated with a diamond-like carbon film, the method includes: a diamond-like carbon film deposition process in which a diamond-like carbon film is formed on a surface of the base material by generating plasma by applying voltage to the base material in a processing chamber that stores the base material, while evacuating the processing chamber and introducing feedstock gas that contains at least a carbon compound into the processing chamber; and a hydrogenation process in which the deposited diamond-like carbon film is hydrogenated using hydrogen gas by stopping the voltage application and introducing hydrogen gas inducted instead of the feedstock gas, while the evacuation is being continued.
    Type: Grant
    Filed: May 27, 2011
    Date of Patent: May 21, 2013
    Assignee: JTEKT Corporation
    Inventors: Masahiro Suzuki, Toshiyuki Saito, Kazuyoshi Yamakawa
  • Patent number: 8444726
    Abstract: A grinding wheel is manufactured such that (a) any one of particles for an abrasive grain layer and particles for a substrate layer are put into the press-mold die, and other particles are put onto the particles in the press-mold die, and then the substrate layer and the abrasive grain layer are integrally press-molded to form a non-baked grinding chip with an arcuate shape; (b) depressions are formed on the abrasive grain layer of the non-baked grinding chip; (c) the grinding chip on which the depressions are formed is baked; and (d) the plurality of baked-grinding chips are adhered to a core of the grinding wheel.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: May 21, 2013
    Assignees: JTEKT Corporation, Toyoda Van Moppes Ltd.
    Inventors: Shinji Soma, Koji Morita, Tomohiro Inagaki, Takayuki Moroto, Kazuhiko Sugita, Tomoyasu Imai, Yasuji Kunihiro
  • Patent number: 8443689
    Abstract: A rack shaft support device includes: a rack shaft support member that slidably supports a rack shaft; a sealing member fixed to an inlet port of a retention hole formed in a housing; an intermediate member that is interposed between the rack shaft support member and the sealing member; a torsion spring that couples the intermediate member so that torque is transmitted to the intermediate member; a torsion amount adjusting member that is attached to the sealing member in such a manner that a position of the torsion amount adjusting member with respect to the sealing member is adjustable and adjusts a torsion amount of the torsion spring; and a cam mechanism that converts a rotation force of the intermediate member induced by untwisting of the torsion spring into a force by which the intermediate member pushes the rack shaft support member.
    Type: Grant
    Filed: July 22, 2009
    Date of Patent: May 21, 2013
    Assignee: JTekt Corporation
    Inventors: Akitake Kawakubo, Yoshinori Suzuki, Hirofumi Ishimi
  • Patent number: 8447470
    Abstract: The invention concerns a method which includes: filtering the torque signal using a low-pass filter of the first order at a variable cut-off frequency which takes on, respectively, a minimum value or a maximum value depending on whether the amplitude of the torque signal is, respectively, lower or higher than a predetermined threshold; then in producing a signal indicating, respectively, a steering wheel release or a steering wheel grip depending on whether the amplitude of the filtered torque signal is, respectively, lower or higher than a predetermined threshold.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: May 21, 2013
    Assignee: JTEKT Europe
    Inventors: Julien Barthomeuf, Stephane Cassar
  • Publication number: 20130119627
    Abstract: When a motor vehicle is steered, as turning reaction forces from the road surface, for example, rearward radial loads are applied from rear wheels to corresponding end portions of a steered shaft via corresponding knuckles and corresponding tie rods. A motor vehicle steering system includes first and second counter load application mechanisms that apply counter loads against the radial loads to the corresponding end portions of the steered shaft. Each of the counter load application mechanisms includes a motion conversion mechanism that converts torsional motion of the corresponding end portion of an axle beam caused by a ground contact reaction force of the corresponding rear wheel via the corresponding knuckle and a corresponding king pin into, for example, forward motion of the corresponding end portion of the steered shaft.
    Type: Application
    Filed: August 31, 2011
    Publication date: May 16, 2013
    Applicant: JTEKT CORPORATION
    Inventor: Takashi Tashiro
  • Publication number: 20130121755
    Abstract: An annular groove, in which a lower end of a boot is fitted, is formed in an outer periphery of an open end of a housing so as to extend in a circumferential direction of the housing. The annular groove is defined by a cylindrical face, an upper inner wall, and a lower inner wall. By fitting a clip onto a cylindrical portion of the lower end of the boot, the cylindrical portion is pushed against the cylindrical face, and an inner end portion and a folded-back portion are pushed against the upper inner wall and the lower inner wall, respectively. The inner end portion has an annular protrusion that is engaged with the upper inner wall and elastically contracted when the lower end of the boot is fitted in the annular groove.
    Type: Application
    Filed: November 14, 2012
    Publication date: May 16, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT CORPORATION
  • Publication number: 20130118827
    Abstract: An electric power steering system includes elastic members arranged at respective axial ends of a first bearing by which a motor shaft that serves as a hollow shaft is rotatably supported and which elastically support the first bearing relative to a rack housing in the axial direction; and a support member disposed on the outer periphery of the first bearing to support the first bearing with displacement of the first bearing in the radial direction restricted. The motor shaft is disposed so as to move relative to the rack housing in the axial direction as the first bearing slides relative to the support member while elastically deforming the elastic members and a second bearing moves in the axial direction.
    Type: Application
    Filed: November 8, 2012
    Publication date: May 16, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT Corporation
  • Publication number: 20130118826
    Abstract: A power steering system includes: a hydraulic cylinder that generates a steering assist force; a hydraulic control valve that has a spool that adjusts the state of supply and drainage of the hydraulic fluid to and from the hydraulic cylinder based on a position of the spool; a driving unit that displaces the spool by driving the spool with a predetermined driving force; and a determination unit that determines that there is an abnormality in the hydraulic control valve when the driving force for displacing the spool falls outside a predetermined range.
    Type: Application
    Filed: October 30, 2012
    Publication date: May 16, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT CORPORATION
  • Publication number: 20130118289
    Abstract: A vehicle steering system includes a steered shaft, and stoppers which restrict an amount of movement of the steered shaft in an axial direction. The steered shaft has first outer peripheral faces, second outer peripheral faces, and annular stepped portions. Each stepped portion includes a contact portion that faces a corresponding one of the stoppers in the axial direction, a first corner portion that has a concave curved sectional shape and connects the first outer peripheral face to an inner end of the contact portion, and a second corner portion that has a concave curved sectional shape with a larger curvature radius than that of the first corner portion, and connects the first outer peripheral face to the second outer peripheral face, at a position in front of or behind a central axis of the steered shaft.
    Type: Application
    Filed: November 13, 2012
    Publication date: May 16, 2013
    Applicant: JTEKT CORPORATION
    Inventor: JTEKT Corporation