Patents Assigned to JTEKT
  • Patent number: 9020629
    Abstract: Loads that act on all the bearings that support a main spindle are derived from a variation in the state of the main spindle and, in addition, raceway surface contact pressures of the respective bearings are analyzed, so it is possible to accurately keep track of the state of each bearing. Then, when the raceway surface contact pressure exceeds a corresponding threshold, a machining condition is changed to execute control such that the raceway surface contact pressure does not exceed the corresponding threshold, and, furthermore, when the raceway surface contact pressure exceeds the corresponding threshold even when the machining condition is changed, the main spindle is controlled to stop, so it is possible to prevent a seizure of each bearing. Thus, it is possible to improve machining accuracy by controlling the main spindle with high accuracy.
    Type: Grant
    Filed: September 22, 2010
    Date of Patent: April 28, 2015
    Assignee: JTEKT Corporation
    Inventor: Shigeru Matsunaga
  • Patent number: 9011007
    Abstract: A spindle unit includes: a main spindle that holds a rotary tool, and that is rotated; bearings by which the main spindle is rotatably supported; and a damper bearing by which the main spindle is rotatably supported, and that has a damping coefficient larger than damping coefficients of the bearings. The damping coefficient of the damper bearing is set to a value within a range from 10,000 to 1,000,000 N·s/m.
    Type: Grant
    Filed: June 11, 2013
    Date of Patent: April 21, 2015
    Assignee: JTEKT Corporation
    Inventors: Shigeru Matsunaga, Toshiyuki Okita, Ryota Tanase
  • Patent number: 9014853
    Abstract: A pair of manipulators are caused to take a plurality of attitudes in a state where distal ends of the manipulators are coupled to each other, coordinates of joints between links at each attitude change are acquired on the basis of detection signals, at each attitude change, of rotary encoders provided for servomotors that drive the links of the manipulators, and a position and attitude of an installation point of a slave robot with reference to an installation point of a master robot are calculated on the basis of the joint coordinates acquired at the corresponding attitude change in a forward kinematics manner. A deviation vector for each attitude change between actual measured values of the installation point of the slave robot and the calculated values of the installation point of the slave robot is calculated, and robot constants of both manipulators are identified from the deviation vector.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: April 21, 2015
    Assignee: JTEKT Corporation
    Inventors: Hiromichi Ohta, Yasuharu Mukai, Kazuya Numazaki
  • Patent number: 9010806
    Abstract: In a steering system, a first through-hole is formed in a stationary bracket secured to vehicle body. A second through-hole is formed in a movable bracket that is movable relative to the stationary bracket in a prescribed direction at the time of a secondary collision. A pin passed through both the first through-hole and the second through-hole breaks at a position between the first through-hole and the second through-hole at the time of the secondary collision, thereby allowing the movable bracket to move relative to the stationary bracket. An under plate attached to the movable bracket closes the second through-hole from below.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: April 21, 2015
    Assignee: JTEKT Corporation
    Inventors: Eiji Tanaka, Susumu Imagaki, Hiroyuki Yao, Takeshi Matsuda
  • Patent number: 9010199
    Abstract: A stator includes: cylindrical stator cores, each of which is formed of a laminated structure of electromagnetic steel sheets and at which an exciting coil and a detection coil are wound; and a mounting seat portion that is fixedly fitted to axial end faces of the stator cores. Insertion holes through which inserting bolts are passed are formed in the mounting seat portion.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: April 21, 2015
    Assignee: JTEKT Corporation
    Inventor: Toshiaki Murakami
  • Patent number: 9011019
    Abstract: A roller bearing capable of effectively improving the service life of the roller bearing is provided by performing surface treatment with coating. A cylindrical roller bearing includes: an outer ring having an outer ring raceway surface; an inner ring having an inner ring raceway surface that faces the outer ring raceway surface; and a plurality of cylindrical rollers rollably disposed between the outer ring raceway surface and the inner ring raceway surface. The inner ring raceway surface of the inner ring is provided with a black oxidation coating, and a rolling contact surface of each cylindrical roller is provided with a diamond-like carbon coating.
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: April 21, 2015
    Assignee: JTEKT Corporation
    Inventors: Yasuhiro Kobayashi, Ryohei Hosaka
  • Patent number: 9010482
    Abstract: A knurled press-fitting portion and an annular groove, which receives foreign matter and is formed to extend in a circumferential direction in front of the press-fitting portion of a cylindrical protruding portion, are provided at an outer peripheral surface of the protruding portion of an output shaft. A fitting portion, which is fitted to a coupling tube by press-fitting, is formed at an outer periphery of an opening end of the protruding portion. An outer peripheral surface of the cylindrical fitting portion and an inner peripheral surface of the cylindrical coupling tube coupled to a Z4 gear are fitted and coupled to each other. The annular groove is closed by the fitting portion in a state where the protruding portion and the coupling tube are coupled to each other. The annular groove is configured so as to prevent foreign matter from being discharged toward a bearing gear.
    Type: Grant
    Filed: November 7, 2013
    Date of Patent: April 21, 2015
    Assignee: JTEKT Corporation
    Inventor: Satoshi Motoyama
  • Publication number: 20150104126
    Abstract: The conical roller bearing includes an inner ring which includes an annular groove between an inner-ring-side raceway surface and a small-diameter-side end portion thereof, and a cage which includes an erected portion extending from a first annular portion of the cage towards the annular groove. The erected portion includes a first inclined portion and a second inclined portion. The first inclined portion is inclined towards conical rollers disposed in pockets of the cage while extending from the first annular portion towards the annular groove. The second inclined portion is inclined towards the small-diameter-side end portion while extending from the first inclined portion towards the annular groove. The second inclined portion is configured to be brought into engagement with the annular groove in an axial direction of the inner ring.
    Type: Application
    Filed: October 10, 2013
    Publication date: April 16, 2015
    Applicant: JTEKT CORPORATION
    Inventors: Ryosuke CHUDO, Motoshi KAWAMURA, Yoshihito NAKASHIMA
  • Patent number: 9004772
    Abstract: A rolling bearing unit includes: a rolling bearing; a grease reservoir in which grease is reserved; an outer ring spacer disposed adjacent to an outer ring of the rolling bearing; and a bellows-shaped grease medium that connects a second side wall that defines the grease reservoir on the outer ring spacer side, to a step portion of the outer ring. The grease medium is disposed so as to be impregnated with a base oil contained in the grease.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: April 14, 2015
    Assignee: JTEKT Corporation
    Inventor: Kiyoshi Tanimoto
  • Patent number: 9005067
    Abstract: When an outer ring is fitted to an inner periphery of an input member, which defines a center hole, and an inner ring is fitted to an eccentric portion with clearances in a reduction-transmission mechanism, in a state where tooth tips of the input member contact bottomlands of a rotation force applying member on a line perpendicular to a second axis and a fourth axis, a size between the second axis and a third axis is set to a size that is smaller than or equal to half of a size obtained by adding a diameter difference between an outside diameter of a ball bearing and an inside diameter of the input member, which defines the center hole, a diameter difference between an inside diameter of the ball bearing and an outside diameter of the eccentric portion and an operating clearance of the ball bearing.
    Type: Grant
    Filed: January 2, 2013
    Date of Patent: April 14, 2015
    Assignee: JTEKT Corporation
    Inventors: Hiroshi Takuno, Kunihiko Suzuki, Keita Nomura, Tsune Kobayashi, Tohru Onozaki, Masaharu Tagami
  • Patent number: 9004222
    Abstract: An electric power steering apparatus transmits rotational force of a motor to a rack shaft via a driver pulley, a belt, a driven pulley, and a ball nut. A ball bearing and the driven pulley are fitted to the outer circumferential surface of the ball nut. Also, the ball nut is rotationally supported to the inner circumferential surface of a housing via the ball bearing. A female thread portion is formed on the inner circumferential surface of the driven pulley. The ball nut has a male thread portion formed in a first end and a flange formed in a second end. By fastening the male thread portion and the female thread portion to each other, the ball bearing is clamped between the flange and the driven pulley, while the ball nut and the driven pulley are fastened to each other.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: April 14, 2015
    Assignee: Jtekt Corporation
    Inventors: Tetsuya Kaneko, Toshihiro Asakura, Yuichi Yamanaka
  • Patent number: 9005043
    Abstract: A wheel supporting device includes: a hub unit that has a rotary ring having a first spline on its axially inner end face; and a joint that has an outer ring having a second spline, meshing with the first spline, on its axially outer end face. At least one projection included in a plurality of projections of the first spline projects in the axial direction by a larger amount than the remaining projections of the first spline. When a crest of the at least one projection contacts a crest of one of projections of the second spline, a play is caused between the rotary ring and the outer ring due to the at least one projection that works as a fulcrum.
    Type: Grant
    Filed: July 31, 2012
    Date of Patent: April 14, 2015
    Assignee: JTEKT Corporation
    Inventors: Hajime Watanabe, Toshihiro Hakata, Shinichi Mizuta
  • Patent number: 9005038
    Abstract: A rotation transmitting apparatus includes a first shaft on which multiple external teeth are formed so as to be arranged in a circumferential direction, and a second shaft in which multiple internal teeth are formed so as to be arranged in the circumferential direction, the second shaft being fitted to the first shaft so as to be slidable relative to the first shaft in the axial direction and so as to be engageable with the first shaft in a rotational direction through the use of the external teeth and the internal teeth. A protrusion is formed on the tooth flank of one of the external tooth and the internal tooth, the protrusion being projected toward the corresponding tooth flank of the other of the external tooth and the internal tooth. The protrusion is made of a resin that is more elastically deformable than the tooth flank.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: April 14, 2015
    Assignee: JTEKT Corporation
    Inventors: Koichi Nabeshima, Eiji Kaneuchi, Yoshimasa Yamada, Ryousuke Imai
  • Patent number: 9006818
    Abstract: An insulated gate field effect transistor configured to reduce the occurrence of a short-circuit fault, and a method of manufacturing the insulated gate field effect transistor are provided. A FET includes a semiconductor substrate, a gate insulator, a gate electrode, and a conductive member. The semiconductor substrate has an insulation groove that splits a channel region into a first channel region on a drain region side and a second channel region on a source region side. The conductive member is supported by a drain-side end face and a source-side end face of the insulation groove. When the temperature of the conductive member is equal to or higher than a predetermined temperature, the conductive member is cut.
    Type: Grant
    Filed: February 14, 2014
    Date of Patent: April 14, 2015
    Assignee: JTEKT Corporation
    Inventors: Satoshi Tanno, Yasuyuki Wakita
  • Patent number: 8997602
    Abstract: When clamped side plates of an upper column bracket (movable bracket) are fastened via clamping side plates of an upper fixed bracket by a fastening shaft in response to a rotating operation of an operating lever, the brackets are locked with each other. A pressing mechanism that includes a pressing member moves in the axial direction of the fastening shaft in accordance with fastening by the fastening shaft, and presses a lower tube (inner tube) through an insertion hole formed in an upper tube (outer tube). The entirety of the axial force of the fastening shaft is used as a retaining force for retaining the posture of a steering column.
    Type: Grant
    Filed: December 13, 2012
    Date of Patent: April 7, 2015
    Assignee: JTEKT Corporation
    Inventor: Eiji Tanaka
  • Patent number: 8997919
    Abstract: A motor-driven steering controller for controlling a steering wheel of a vehicle. The controller includes a steering torque controlling unit, a braking force estimating unit, a right and left braking force difference estimating unit and an assist steering torque providing unit. The steering torque controlling unit controls a steering torque on the steering wheel depending on a steering operation. The braking force estimating unit estimates braking forces to be imposed on wheels of the vehicle. The right and left braking force difference estimating unit estimates difference between the braking forces to be imposed on the right and left wheels each estimated by the braking forces estimating unit. The assist steering torque providing unit provides an assist steering torque for the steering torque controlling unit on the basis of the difference in braking force between right and left wheels estimated by the right and left braking force difference estimating unit.
    Type: Grant
    Filed: March 5, 2010
    Date of Patent: April 7, 2015
    Assignees: Aisin Seiki Kabushiki Kaisha, Jtekt Corporation, Advics Co., Ltd.
    Inventors: Yoshiyuki Yasui, Wataru Tanaka, Yuji Muragishi, Eiichi Ono, Katsuhiro Asano, Minekazu Momiyama, Hiroaki Kato, Kenji Asano
  • Patent number: 8998189
    Abstract: A wave washer is used for a shaft supporting device of an electric power steering system. The wave washer has an annular portion and six outward protrusions. The annular portion has first protrusions that protrude in a first axial direction and second protrusions that are formed so as to continuous with the first protrusions and that protrude in a second axial direction. Each outward protrusion protrudes from an outer periphery of the annular portion in a radially outward direction of the radial direction of the annular portion.
    Type: Grant
    Filed: July 19, 2013
    Date of Patent: April 7, 2015
    Assignee: JTEKT Corporation
    Inventors: Yuichi Toyama, Hiroyuki Takahashi, Kosuke Tsukahara, Fumihiro Kawakami, Tomohiro Niwa, Yoshinobu Muramoto, Naoki Kinouchi, Takaya Tanikawa
  • Patent number: 9002519
    Abstract: A CPU of a robot control device calculates load torque based on the inertia force, centrifugal force or Coriolis force, gravity force, friction torque, and actuator inertia torque applied to a joint axis of each link, each time an orientation parameter indicative of the link position and orientation allowed by a redundant degree of freedom is sequentially changed, under a constraint of end-effector position and orientation as target values. The CPU obtains the link position and orientation at which the ratio of the load torque to the rated torque of a rotary actuator provided for each joint is minimized, while the orientation parameter is being changed, and provides a feed-forward value that gives rise to each load torque obtained when the ratio of the load torque to the rated torque of the rotary actuator is minimized, to a control command generated to the rotary actuator of each joint axis for achieving the end-effector position and orientation as target values.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: April 7, 2015
    Assignee: JTEKT Corporation
    Inventors: Hiromichi Ohta, Yasuharu Mukai, Kazuya Numazaki
  • Patent number: 8998785
    Abstract: A tool radius adjusting device executes an operation for adjusting the tool radius of a boring holder in parallel with execution of a machining program for executing an operation of a spindle head and an operation of a tool changer. A carrier control unit determines whether the tool changer is executing a tool changing process. When the tool changing process is not being executed, the carrier control unit allows the carrier device to execute an operation for picking the boring holder out from the tool magazine and an operation for returning the boring holder, of which the tool radius has been adjusted, to the tool magazine.
    Type: Grant
    Filed: August 25, 2011
    Date of Patent: April 7, 2015
    Assignee: JTEKT Corporation
    Inventors: Eiji Nakamura, Akihiko Kadota, Takashi Yokoyama
  • Patent number: 8998259
    Abstract: A steering apparatus includes an engaging portion movable in a predetermined moving direction at a time of a secondary collision; a fixation portion fixed to a vehicle body; and an absorbing member. The absorbing member includes a fixed portion fixed to the fixation portion, an engaged portion facing the engaging portion, and a connecting portion that includes a curved portion and connects the fixed portion and the engaged portion. An area of a cross-section of the curved portion taken along a plane perpendicular to a creeping direction along the curved portion varies depending on a position in the creeping direction. The connecting portion of the absorbing member is deformed so that the absorbing member absorbs energy of the secondary collision.
    Type: Grant
    Filed: July 11, 2014
    Date of Patent: April 7, 2015
    Assignee: JTEKT Corporation
    Inventors: Shigeru Morita, Tatsutomo Yokozeki, Isao Hasegawa