Patents Assigned to NSK Ltd.
  • Extendable shaft for vehicle steering
    Patent number: 7559267
    Abstract: A telescopic shaft used for steering of a vehicle to be used in the steering shaft of a vehicle has a male shaft and a female shaft that are fitted to each other non-rotatably and slidably. The telescopic shaft is provided with at least one set of torque transmission members disposed in at least one set of intermediate fitting portions formed on the outer circumferential surface of the male shaft and the inner circumferential shaft of the female shaft and a stopper plate for regulating movement of the at least one set of torque transmission members with respect to the axial direction.
    Type: Grant
    Filed: September 18, 2003
    Date of Patent: July 14, 2009
    Assignee: NSK Ltd.
    Inventor: Yasuhisa Yamada
  • CAM FOLLOWER DEVICE
    Publication number: 20090173300
    Abstract: A cam follower device includes a pair of plate-shaped rocker arms 17 parallel mutually, a support shaft 7a fixed in support holes 8a, 8a at one end portions of the rocker arms 17 at both end portions and a tappet roller 9 supported rotatably around a circumference of an intermediate portion of the support shaft 7a. When the cam follower device is built in a valve train, rotary motion of a cam 2 provided on a camshaft is transmitted to valve elements 12 constituting two inlet (or exhaust) valves by the tappet roller 9 and the pair of rocker arms 17 so as to reciprocate the two valve elements 12 axially. By this configuration, the number of components in a valve train of an engine, in which a number of at least one of inlet and exhaust valves per cylinder is two or more, can be reduced.
    Type: Application
    Filed: March 30, 2007
    Publication date: July 9, 2009
    Applicant: NSK LTD.
    Inventor: Noriyuki Takeo
  • State measuring apparatus for rotary machine
    Patent number: 7557569
    Abstract: There are provided first and second characteristic change portions 9 and 10 having characteristic boundary inclination directions different from each other in an inner half portion and an outer half portion of the encoder 4. Detections portions of one pair of sensors 6a1 (6b1, 6c1) and 6a2 (6b2, 6c2) are opposed to three circumferential positions of both the characteristic change portions 9 and 10. A operator has a function of calculating the displacements x, y, z, and inclinations ?x, ?z, on the basis of phase differences among output signals of the sensors 6a1, 6a2, 6b1, 6b2, 6c1, and 6c2.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: July 7, 2009
    Assignee: NSK Ltd.
    Inventors: Koichiro Ono, Nagao Dohi
  • BALL BEARING MANUFACTURING FACILITY AND SUPER FINISH MACHINING APPARATUS
    Publication number: 20090165274
    Abstract: A detection unit of a matching apparatus 32 is connected to a control unit 6 of a computer so that a detection signal indicating measured values of diameters of outer and inner ring raceways can be sent thereinto. An outer ring secondary grinding apparatus 24, an cuter ring super finish machining apparatus 25a, an inner ring secondary grinding apparatus 26 and an inner ring super finish machining apparatus 28a are connected to the control unit 6 so that control signals can be received. The control unit 6 imparts shift amounts to diameter machining target values which are set, respectively, in the grinding apparatus 24, 26 and the super finish machining apparatus 25a, 28a for machining a raceway surface of at least one bearing ring of outer and inner rings, based on measured values of diameters of the outer and inner ring raceways which were measured by the detection unit.
    Type: Application
    Filed: November 22, 2005
    Publication date: July 2, 2009
    Applicant: NSK Ltd.
    Inventors: Natsuki Sensui, Shuji Johnishi, Yosuke Irie
  • Steering column for motor vehicle
    Patent number: 7552945
    Abstract: A steering column is structured such that a clamp/unclamp mechanism of a telescopic mechanism and a tilting mechanism can be operated by a single control lever located in the vicinity of a steering wheel, and that no part juts out of the steering column to improve reliability and controllability. When the control lever is pulled to rock on the center of the lever center axis, a tilt head is unclamped, while the rocking motion of the control lever turns a pusher plate, thereby pushing a pusher rod and also turning a column clamp shaft through a rocking arm. With the rotation of the column clamp shaft, the clamp is released to allow a column head to move. Since the column clamp shaft turns parallelly with the direction of movement of the column head, the column head can be clamped/unclamped regardless of its position.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: June 30, 2009
    Assignee: NSK Ltd.
    Inventors: Kenji Sato, Sakae Matsumoto
  • Control apparatus of electric power steering apparatus
    Patent number: 7548035
    Abstract: The invention relates to a control apparatus of an electric power steering apparatus structured such as to apply a steering assist force generated by a n-phase motor to a steering system of a vehicle, the control apparatus is provided with at least (n?1) numbers of current detecting means for detecting a current Im in each of phases of the motor, a current command value calculating means for outputting a current command value Imref in each of the phases, and n numbers of current control means, and the control apparatus executes a current control of each of the phases by the current control means having the current command value Imref in each of the phases and the current Im in each of the phases as an input.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: June 16, 2009
    Assignees: NSK Ltd., NSK Steering Systems Co., Ltd.
    Inventors: Shuji Endo, Yuho Aoki, Hideyuki Kobayashi, CaoMinh Ta
  • Rolling bearing seal or shield member
    Patent number: 7547146
    Abstract: The present invention is to offer such a rolling bearing excellent in the corrosion resistance and suited to the environmental protection. This rolling bearing rotatably holds, via a retainer, a plurality of rolling elements between an inner ring having an inner ring raceway in an outer circumference and an outer ring having an outer ring raceway in an inner circumference, and is sealed with a seal or a shield member covered with a rubber, wherein a core metal of the seal or the shield member is a steel sheet that is covered with a film of 0.2 to 50 ?m thickness, the film comprising a metal or an alloy having a smaller oxidation-reduction potential than that of iron, and that is formed with a film comprising an inorganic substance of lithium and silica as an uppermost layer.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: June 16, 2009
    Assignee: NSK Ltd.
    Inventors: Dai Kinno, Hiroyuki Ito, Toshikazu Yabe, Shingo Higashi
  • Rolling bearing
    Patent number: 7537392
    Abstract: The present invention provides a rolling bearing which comprises a retainer that can be used without any deformation at high temperatures and fairly assembled to bearing and thus can be used under severe working conditions such as high temperature, high rotary speed and high load over an extended period of time. A novel rolling bearing is provided comprising a retainer made of a resin composition having a flexural modulus of at least 3,500 MPa at 180° C. and a heat-resistant temperature of at least 150° C.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: May 26, 2009
    Assignee: NSK Ltd.
    Inventors: Magozou Hamamoto, Toshihisa Ohata, Koichi Goto, Toshimi Takajo
  • Ball Bearing for Spindle Turning Device of Machine Tool and Spindle Turning Device of Machine Tool Using the Same
    Publication number: 20090131235
    Abstract: A ball bearing for spindle turning device for use in the spindle turning device of a machine tool, and a spindle turning device for a machine tool using the same, which is compatible with machine tools whose recent trend is for more composite configurations while maintaining and achieving higher accuracy (higher rotational accuracy), greater stiffness and reductions in torque and heat generation is to be provided. In a ball bearing for spindle turning device for use in the spindle turning device of a machine tool, the sectional size ratio (B/H) between the axially cut sectional width B and the radially cut sectional height H is set to be (B/H)<0.63 where it is a single row ball bearing or the sectional size ratio (B2/H2) between the axially cut sectional width B2 and the radially cut sectional height H2 (B2/H2)<1.2 where it is a double row ball bearing.
    Type: Application
    Filed: January 12, 2007
    Publication date: May 21, 2009
    Applicant: NSK LTD.
    Inventors: Yoshiaki Katsuno, Mitsuho Aoki
  • THRUST ROLLER BEARING
    Publication number: 20090123105
    Abstract: A thrust roller bearing 10 is provided in which one half of total gap which results from adding up an outer diameter side in-bearing gap 22 and an inner diameter side in-bearing gap 23 in diametrical direction is made larger than the amount of eccentricity between a member 51 which supports an outer ring 11 and a member 53 which supports an inner ring 14. When inside diameter at distal end of an outer locking portion 19 along a distal edge portion of an outer flange 13 is ?D1, outside diameter of a cage 18 is ?D2, outside diameter at a distal end of an inner locking portion 20 along a distal edge portion of an inner flange 16 is ?D3, inside diameter of the cage 18 is ?D4 and thickness of the cage 18 is t, A, B are defined as A=(D2?D1)/t and B=(D3?D4)/t, 0.1?A, B?5 is satisfied.
    Type: Application
    Filed: June 22, 2006
    Publication date: May 14, 2009
    Applicant: NSK LTD.
    Inventors: Satoshi Masuda, Hiromichi Takemura
  • STEERING COLUMN DEVICE
    Publication number: 20090120229
    Abstract: Since a fixed piece 7 is attached to a fixed bracket 1 by means of bolts BT, BT, the impact force by which sliding of a skid bracket 2 is started can be arbitrarily set by adjusting tightening force of the bolts BT, BT.
    Type: Application
    Filed: October 10, 2006
    Publication date: May 14, 2009
    Applicant: NSK. LTD.
    Inventors: Hiroshi Shibazaki, Yasuhisa Yamada
  • CONTROL UNIT OF ELECTRIC POWER STEERING APPARATUS
    Publication number: 20090125187
    Abstract: In a control unit of an electric power steering apparatus for driving a motor with a current command value and giving an assist torque to a steering mechanism by driving the motor, the control unit is provided with a motor angle sensor; a torque sensor; a relative steering angle detecting section for detecting a relative steering angle; a steering angular speed detecting section for detecting an angular speed of the motor; a vehicle speed determining section; a neutral point calculating section for determining that a vehicle is being driven straightly, and calculating by considering that the relative steering angle when the straight driving continues for not less than a predetermined time is a neutral point; and an absolute steering angle calculating section for calculating an absolute steering angle with a difference between the neutral point and the relative steering angle.
    Type: Application
    Filed: October 12, 2006
    Publication date: May 14, 2009
    Applicant: NSK LTD.
    Inventors: Satoshi Yamamoto, Takeshi Hara
  • RACK AND PINION TYPE STEERING DEVICE AND METHOD OF MANUFACTURING THE SAME
    Publication number: 20090120226
    Abstract: A rack and pinion type steering device capable of reducing contact surface pressure, suppressing the wear of contact surfaces, and preventing a rack guide movable amount from being excessively increased by increasing the contact area of the outer peripheral surface of roller on the outer peripheral surface of a rack shaft in a rack guide, and method of manufacturing the steering gear.
    Type: Application
    Filed: November 1, 2006
    Publication date: May 14, 2009
    Applicant: NSK Ltd
    Inventor: Hiroki Nishikubo
  • Electric Power Steering Apparatus
    Publication number: 20090120714
    Abstract: A electric power steering apparatus having a steering torque detecting unit for detecting a steering torque transmitted to the steering system; an electric motor for generating a steering assist force to give to the steering system; a motor control unit for controlling the electric motor based on at least the steering torque. The apparatus comprises a motor stop condition detecting unit for detecting a condition to stop the electric motor while the electric motor is under control by the motor control unit; and an electromagnetic brake control unit over the electric motor in order to suppress a kick-back based on at least either one of a steering condition of the steering system and a running condition of the vehicle when a detection result by the motor stop condition detecting unit shows that a condition occurs to stop the electric motor.
    Type: Application
    Filed: March 13, 2007
    Publication date: May 14, 2009
    Applicant: NSK LTD.
    Inventors: Tomonori Hisanaga, Yoshiki Ninomiya, Shinji Kanai
  • Ball screw mechanism
    Patent number: 7530283
    Abstract: Between two mutually adjoining load balls 5, there is interposed a retaining piece 10 having two concave surfaces 11 which are respectively opposed to the two adjoining load balls 5. The retaining piece 10 has an outside diameter dimension equal to or more than 0.5 times the outside diameter dimension of the load ball 5. Further, the retaining piece 10 has an outside diameter dimension which, when the retaining piece 10 passes through a screw groove circulation passage and a tube circulation passage, prevents the retaining piece 10 from touching the inner walls of these screw groove circulation passage and tube circulation passage, or has an outside diameter dimension which is equal to or less than 0.9 times the outside diameter dimension of the load ball.
    Type: Grant
    Filed: October 31, 2005
    Date of Patent: May 12, 2009
    Assignee: NSK Ltd.
    Inventors: Tsutomu Ohkubo, Takeshi Nakazawa
  • Double row cylindrical roller bearing
    Patent number: 7530743
    Abstract: A cylindrical roller bearing with synthetic resin cages, in which heat generation of the bearing during high speed rotation is suppressed, while sufficient rigidity and strength is secured, so that the bearing is excellent in high speed performance. The cylindrical roller bearing (10) has synthetic resin cages (20) each including an annular portion (21) disposed in one axial end portion of the cage (20), and a plurality of columnar portions (25) extending from a side surface of the annular portion (21). The minimum inner diameter d1 of the annular portion (21) is set to be smaller than the maximum inner diameter d2 of each columnar portion (25), and the inner diameter of the columnar portion (25) is set to be equal to the inner diameter d1 of the annular portion (21) over a range of length not longer than ? of the whole length of the columnar portion (25).
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: May 12, 2009
    Assignee: NSK Ltd.
    Inventors: Kenji Yakura, Takaaki Anzai, Ken Inaba, Yasushi Morita
  • Ball screw apparatus
    Patent number: 7530282
    Abstract: A ball screw apparatus of a screw shaft circulating-type includes a nut having a first groove formed in an inner peripheral surface thereof, a screw shaft having a second groove formed in an outer peripheral surface thereof, and a plurality of rolling elements provided between the first and second grooves. A circulating groove is formed in the screw shaft so as to interconnect opposite ends in a spiral direction of the second groove of the screw shaft to form a closed-loop ball endless circulating passageway. Processing relief portions for preventing a processing tool of a rotary drive-type from interfering with the circulating groove when processing the second groove of the screw shaft by the processing tool are provided respectively at the opposite end portions in the spiral direction of the second groove of the screw shaft.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: May 12, 2009
    Assignee: NSK Ltd.
    Inventors: Shingo Saitou, Koji Hashimoto
  • Wheel supporting bearing unit
    Patent number: 7520676
    Abstract: An IC tag 23 is fixed to a central portion of an axially outer end portion face of a hub 10a which is a rotational ring which makes up the wheel supporting bearing unit 5a. Historical information of the wheel supporting bearing unit 5a is stored in the IC tag 23. The historical information stored in the IC tag 23 can be read easily by the use of an external device 28. Due to this, the traceability of the wheel supporting bearing unit 5a can be increased.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: April 21, 2009
    Assignee: NSK Ltd.
    Inventors: Akira Takahashi, Tatsuo Wakabayashi
  • Continuously variable transmission system
    Patent number: 7520832
    Abstract: A sleeve 28 making up a gear ratio control valve 21 is driven by not only a stepping motor 29 but also a secondary actuator 47. Pressure oil is made free to be introduced into the secondary actuator 47 through a manual oil pressure switching valve 37 which is switched over by a gearshift. Then, when the gearshift is operated from a non-running state to a running state, a gear ratio of a toroidal type continuously variable transmission is corrected by a predetermined amount by driving the sleeve 28 by the secondary actuator 47. As a result, while improving characteristic of a vehicle when starting from rest, the vehicle can be prevented from being reduced in speed unintentionally excessively even when the gearshift is operated while running.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: April 21, 2009
    Assignee: NSK Ltd.
    Inventors: Toshiro Toyoda, Eiji Inoue, Takashi Imanishi, Takumi Sinojima
  • Joint section between a shaft and a universal-joint yoke
    Patent number: 7517284
    Abstract: In a joint section between a shaft and a universal-joint yoke a tip surface on the tip end of the shaft and an inside surface of a connecting section of the yoke fit together in concave-convex engagement. The tip surface contacts the inside surface at two contact locations, and a clearance between these surfaces is formed between the two contact locations, whereby movement of the tip end of the shaft is restricted and vibration of the shaft is prevented.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: April 14, 2009
    Assignee: NSK Ltd.
    Inventor: Hiroshi Sekine