Patents Assigned to Hitachi Automotive Systems Steering, Ltd.
  • Publication number: 20180229765
    Abstract: A power steering apparatus includes: a steering load average value calculating circuit 39 which calculates a steering torque average value Trav which is the average value of steering torque Tr within a predetermined interval of time; and an abnormality detection circuit 40 which compares steering torque average value Trav with a specified steering torque value Trrf and detects the abnormality of the apparatus when steering torque average value Trav is larger than the specified value.
    Type: Application
    Filed: April 17, 2018
    Publication date: August 16, 2018
    Applicant: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventor: Mitsuo SASAKI
  • Patent number: 9994252
    Abstract: A power steering apparatus includes: a steering load average value calculating circuit 39 which calculates a steering torque average value Trav which is the average value of steering torque Tr within a predetermined interval of time; and an abnormality detection circuit 40 which compares steering torque average value Trav with a specified steering torque value Trrf and detects the abnormality of the apparatus when steering torque average value Trav is larger than the specified value.
    Type: Grant
    Filed: June 15, 2017
    Date of Patent: June 12, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventor: Mitsuo Sasaki
  • Patent number: 9988080
    Abstract: In a power steering device and a control device for a vehicle-mounted instrument, an abnormality detection accuracy of sensor output signals is increased. In an electric power steering device and a control device for a vehicle-mounted instrument, judgment for the abnormality of the sensor output signals is carried out by using at least four or more sensor output signals, in which when the sensor output signals satisfy both a first condition (viz., the number of the output signals showing an identical value is the largest) and a second condition (viz., the number is equal to or larger than “n+1”) (n=the largest number of the sensor output signals that have a common factor), judgement is so made that the sensor output signals that satisfy the first and second conditions are normal and the other signals are abnormal.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: June 5, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Mitsuo Sasaki, Takumi Hisazumi
  • Patent number: 9919729
    Abstract: A power steering system is provided with a communicating hole and yet ensures the strength of a housing. Space between the housing and a wheel turning shaft is divided into two. Space located on one axial side of the bearing supporting a nut and the plurality of balls disposed in the nut is a first chamber, and space located on the other side is a second chamber. The communicating hole allowing communication between the first and second chambers is formed in the nut to open in the nut-side ball screw groove, avoiding a region in which the balls circulate, or in a member disposed radially further outside than the nut and radially inside than the inner wall of the housing.
    Type: Grant
    Filed: July 29, 2014
    Date of Patent: March 20, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Satoru Muto, Keisuke Kitamura, Tatsuyoshi Maruyama
  • Patent number: 9903366
    Abstract: A variable displacement vane pump includes first and second sealing grooves formed on an intake port side and separated away from each other in a circumferential direction; first and second sealing members provided in the first and second sealing grooves; a first fluid-pressure chamber formed on a side on which a volume thereof decreases when the cam ring moves to a side on which an eccentricity of the cam ring increases; and a second fluid-pressure chamber formed on a side on which a volume thereof increases when the cam ring moves to a side on which the eccentricity of the cam ring increases; and a control valve configured to control the pressure in the first or second fluid-pressure chamber.
    Type: Grant
    Filed: February 11, 2015
    Date of Patent: February 27, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventor: Yoshiaki Kido
  • Patent number: 9873851
    Abstract: Provided are both a grease composition for an electric power steering device and an electric power steering device. The grease composition can keep a sufficiently low coefficient of friction in a sliding area between a steel and a resin over a long period, is less susceptible to being removed from the sliding area, does not cause break down of an oil film, and thus can minimize the occurrence of stick-slips. A grease composition for an electric power steering device, containing a synthetic hydrocarbon oil which exhibits a density of 0.75 to 0.95 g/cm3 at 15° C., a saturated aliphatic amide compound, boron nitride, a glycerin fatty acid partial ester, and a metal soap-based thickener; and an electric power steering device using the grease composition.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: January 23, 2018
    Assignees: JX NIPPON OIL & ENERGY CORPORATION, HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Takashi Arai, Kazumi Sakai, Yuji Shitara, Satoshi Taniuchi, Kohtaro Shiino, Tatsuro Suzuki
  • Patent number: 9863417
    Abstract: A variable displacement vane pump is provided. This pump includes a pump housing including, a driving shaft, a rotor, a plurality of vanes, a cam support surface, a cam ring, an intake port formed at the pump housing, a discharge port formed at the pump housing, and a cam ring control mechanism disposed at the pump housing and configured to control an eccentric amount of the cam ring with respect to the rotor. The cam support surface is formed in such a manner that a shortest distance between the cam support surface and a reference line decreases from a second confining region side toward a first confining region side, and the cam ring is formed in such a manner that a cam profile radius change rate decreases first and then increases again on the second confining region side when eccentric amount of the cam ring is maximized.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: January 9, 2018
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Norikazu Kumasaka, Masaaki Iijima, Yukio Uchida, Satoshi Muramatsu
  • Patent number: 9828991
    Abstract: A variable displacement vane pump includes a notch portion which is a flow path provided to extend from an initiating end of a discharge port towards a terminating end side of a suction port. The notch portion is formed so that a sectional area of the flow path is smaller than a sectional area of the discharge port at the initiating end thereof and that a length of the flow path in a circumferential direction is 1.5 pitches or larger. The terminating end of the suction port is a point where the vane in the suction area last overlaps the suction port. The initiating end of the discharge port is a point where the vane departed from the suction area first overlaps the discharge port. One pitch is a distance defied in the circumferential direction between adjacent vanes of the plurality of vanes.
    Type: Grant
    Filed: March 17, 2015
    Date of Patent: November 28, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Satoshi Muramatsu, Yutaka Ogiwara, Masaaki Aoki, Norikazu Kumasaka, Yoshiaki Kido
  • Patent number: 9796409
    Abstract: In a power steering device and a vehicle-mounted instrument, an abnormality detection accuracy of a state quantity detection means is increased. In an electric power steering device and a vehicle-mounted instrument that are each provided with a plurality of state quantity detection means, an abnormality detection for the state quantity detection means is carried out by comparing detection signals issued from the state quantity detection means provided on a redundant system, and by comparing the detection signals issued from the state quantity detection means with signals that are issued from other state quantity detecting means and calculated to be matched with the same unit as the compared detection signals, a value or close value that is possessed by the largest number of signals is set as a normal value.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: October 24, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Mitsuo Sasaki, Takumi Hisazumi
  • Patent number: 9796414
    Abstract: In order to suppress an electric power steering device from generating a contact noise due to operation of a mechanical stopper and a rack stopper, there is provided a control unit in which a command signal Io applied to an electric motor used for assisting the steering power is calculated taking into consideration both a rack stopper side damping correction represented by a rack side damping correction signal Dr calculated in a rack side damping correction amount calculation part 21 and a mechanical stopper side damping correction represented by a mechanical side damping correction signal Dm calculated in a mechanical side damping correction amount calculation part 23.
    Type: Grant
    Filed: October 5, 2015
    Date of Patent: October 24, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Yasuhito Nakakuki, Kazuya Yamano
  • Publication number: 20170282969
    Abstract: A power steering apparatus includes: a steering load average value calculating circuit 39 which calculates a steering torque average value Trav which is the average value of steering torque Tr within a predetermined interval of time; and an abnormality detection circuit 40 which compares steering torque average value Trav with a specified steering torque value Trrf and detects the abnormality of the apparatus when steering torque average value Trav is larger than the specified value.
    Type: Application
    Filed: June 15, 2017
    Publication date: October 5, 2017
    Applicant: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventor: Mitsuo SASAKI
  • Patent number: 9714657
    Abstract: A variable displacement vane pump and a power steering can secure a discharge flow rate when a steering wheel is turned, and restrict the discharge flow rate when the steering wheel is not turned. In the variable displacement vane pump and power steering system, a bypass line is formed. The bypass line causes a hydraulic fluid in a high pressure chamber of a control valve, which controls an eccentricity of a cam ring, to flow directly to a low pressure chamber side of the control valve. The hydraulic fluid flows directly to the low pressure chamber side of the control valve when the steering wheel is turned.
    Type: Grant
    Filed: February 19, 2014
    Date of Patent: July 25, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Yukio Uchida, Hiroki Imanaga, Satoshi Muramatsu
  • Patent number: 9707994
    Abstract: A power steering apparatus includes: a steering load average value calculating circuit 39 which calculates a steering torque average value Trav which is the average value of steering torque Tr within a predetermined interval of time; and an abnormality detection circuit 40 which compares steering torque average value Trav with a specified steering torque value Trrf and detects the abnormality of the apparatus when steering torque average value Trav is larger than the specified value.
    Type: Grant
    Filed: January 20, 2014
    Date of Patent: July 18, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventor: Mitsuo Sasaki
  • Patent number: 9694847
    Abstract: A ball bearing for rotatably supporting a steering shaft, which is comprised of an input shaft and an output shaft connected to each other via a torsion bar is secured by a lock nut. The lock nut has an inside diameter Y1 greater than a maximum outside diameter X6 of the sensor body of a torque sensor mainly configured from a permanent magnet, first and second yoke members, and a magnetic sensor, which are disposed on the outer periphery of the steering shaft. With this configuration, the torque sensor and the lock nut radially overlap with each other, thus reducing the size of a device. Also, because of the lock nut being assembled so as to pass through the outer peripheral side of the torque sensor, component parts can be installed from one direction, thus improving the assembling workability of the device.
    Type: Grant
    Filed: January 20, 2014
    Date of Patent: July 4, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Osamu Yoshida, Tatsuyoshi Maruyama, Kiyotaka Shirakubo
  • Patent number: 9540041
    Abstract: After a Hall IC sensor is set in a connector in such a manner that the Hall IC sensor and a harness are electrically connected to each other, the connector and the Hall IC sensor are inserted from an opposite side of a connector insertion hole in a radial direction toward one side of the connection insertion hole in the radial direction, and a first magnetism collection ring and a second magnetism collection ring are inserted into a torque sensor container portion from a first opening portion in such a manner that the Hall IC sensor is situated between the first magnetism collection ring and the second magnetism collection ring in the radial direction.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: January 10, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Hiroki Murakami, Shinichi Isobe, Kohtaro Shiino
  • Patent number: 9511797
    Abstract: A first valve accommodation hole is provided in a valve housing. A first valve element, a first valve seat member, a first coil spring, and a first pin are directly accommodated and disposed in the first valve accommodation hole. It is thereby possible to reduce the maximum diameter t1 of the first valve accommodation hole, thus reducing the size of a housing main body.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: December 6, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Sosuke Sunaga, Shogo Ishikawa
  • Patent number: 9505433
    Abstract: A power steering apparatus includes a worm gear that transmits a rotational force of an electric motor to a steering mechanism through engagement of a worm shaft and a worm wheel and a backlash adjustment mechanism that reduces backlash between the worm shaft and the worm wheel. The backlash adjustment mechanism has a ball bearing mounted to the worm shaft, a slider movable in a movement direction substantially perpendicular to a rotation axis of the worm shaft, a first sliding surface provided on an outer circumferential side of an outer race of the ball bearing, and a second sliding surface provided on the slider and brought in sliding contact with the first sliding surface such that forward movement of the slider in the movement direction causes relative sliding of the first and second sliding surfaces to bring the worm shaft closer to the worm wheel.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: November 29, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventor: Susumu Kimoto
  • Patent number: 9505431
    Abstract: A rotation detecting device includes first and second members that are rotatable relative to each other around a rotation axis, a magnetic member fixed to the first member and having poles alternately arranged around the rotation axis, a detecting member arranged to face the magnetic member and made of a magnetic material, and a holding member fixed to the second member. The holding member is made of thermoplastic resin and includes first and second holding members that are welded and fixed to each other. The detecting member is disposed between the first and second holding members to prevent relative contact between the detecting member and the second member. The rotation detecting device further includes a magnetic sensor that detects relative rotation between the first and second members by sensing a change of magnetic field in the detecting member due to the relative rotation.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: November 29, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Osamu Yoshida, Tatsuyoshi Maruyama, Kiyotaka Shirakubo
  • Patent number: 9487230
    Abstract: For compensation for loss of a steering assist force due to friction of a steering mechanism, when calculating a friction correction value for the compensation, in an electronic control unit 6, a static friction and a kinetic friction are distinguished, and the calculation is made by combining the static friction correction value Sf and the kinetic friction correction value Kf according to each friction. It is therefore possible to make a proper friction loss compensation according to type of the friction.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: November 8, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Haruto Sakuma, Masaki Kodato, Kazuya Yamano
  • Patent number: 9457836
    Abstract: A power steering apparatus has a first characteristic which is a characteristic of a command signal with respect to steering torque and a second characteristic which is a characteristic different from the first characteristic. When switching is to be made to a characteristic selected from between the first and second characteristics, an interpolation characteristic intermediate between the first and second characteristics is calculated so that the characteristic used before switching of the characteristics gradually approaches the characteristic to be used after the switching, and a characteristic switching time for switching between the first and second characteristics is variably controlled in accordance with the steering torque.
    Type: Grant
    Filed: September 22, 2014
    Date of Patent: October 4, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS STEERING, LTD.
    Inventors: Masaki Kodato, Kazuya Yamano